Aim: Excessive exposure of drivers to traffic noise and the resulting hearing loss could affect safe driving. This study aimed to investigate the hearing status of heavy vehicle drivers and its correlation with traffic accidents. Materials and Methods: This cross-sectional study was conducted on 187 drivers of heavy vehicles (trucks and buses) in Tehran province during 2018. The hearing status of drivers was investigated by the audiometric test method, ISO 6189 (1983). A safety questionnaire and checklist of drivers' demographic variables were used to gather information on accident status and personal characteristics of drivers. SPSS version 24 software was used for the statistical analysis of data. The statistical tests used are Chi-square, Spearman's correlation, paired t-test, and odds ratio. Results: Examining the hearing status of drivers showed that 51.5% were normal and 48.5% of drivers had hearing loss. The highest mean hearing threshold was at a frequency of 4000 Hz. The mean (standard deviation) for the right and left ears was 27.82 ± 15.92 and 18 ± 27.32 dB, respectively. The results of the analysis on drivers' hearing status and accidents showed a significant correlation between the frequency of accidents and the classification of drivers' hearing loss. Thus, a significant relationship with the correlation coefficient of 0.123 and 0.307, respectively, was obtained between the average hearing loss of drivers and having one or five accidents. Conclusion: The findings of the study showed hearing loss in drivers in the left ear, especially at high frequencies. There is also a significant relationship between the number of accidents and the rate of hearing loss of drivers. Hearing loss caused by noise interferes with activities such as driving and negatively affects the safety of drivers and emphasizes the importance of preventing accidents by controlling traffic noise.

Aims: The steady development of human communities and the spread of industrial activities are major contributors to environmental pollution, especially the contamination of water resources. Population growth and thus the acceleration of municipal, industrial, and agricultural wastewater release have adversely affected these inestimable resources and restricted their accessibility. This work attempts to identify the ecogeomorphological condition of rivers in drainage basins emphasizing the Siminehrood River in Northwestern Iran. The purpose is to study all nonpoint source (PS) and PS pollutions and circumstances that weaken and intensify the pollution rate and self-purification capacity of rivers, especially in the Siminehrood River. Materials and Methods: All data and statistics were collected and their seasonal average was calculated. Maps and variables associated with the physical properties of drainage basins were then extracted through ArcGIS. The Schuler diagram was plotted through Chemistry software for all stations and each season to assess the type and chemical quality of the river's drinking water. HEC-RAS model, HEC-GEORAS extension, and ArcGIS were employed for simulation of river flow and calculation and determination of water surface profiles and other hydraulic characteristics of flow including water depth, water flow rate, stream shear stress, and stream power. Results: According to the analyses and results, the improper ecogeomorphological condition of rivers and their low self-purification capacity are directly correlated with the mean river water depth, water flow rate, slope of the river basin, and environmental differences. Conclusions: Within the study area, the highest environmental instability and the least self-purification capacity were observed downstream of the sub-basin in which the mean and maximum depth of water were, respectively, 3.10 m and 8.803 m. Insignificant water flow rate (0.86 m/s on average) and slope of <4% in the area have stagnated water flow in most areas and consequently declined the content of dissolved oxygen and the quality of water. Conclusively, this sub-basin can be reported as a region with an improper ecogeomorphological condition.

Aim: One of the most harmful agents in construction sites is heat exposure. The aim of this study was to evaluate the performance of new evaporative cooling vests in construction workers. Materials and Methods: This case–control study was implemented on 60 construction workers in hot conditions (air temperature 49.0°, relative humidity 5.5%) in the summer of 2019. In this study, 30 people with cooling vests (case group) and 30 people without cooling vests (control group) were working for 120 min in a hot environment. In both groups, heart rate oral temperature and wet bulb globe temperature (WBGT) index were measured. Moreover, the Perceptual Strain Index (PeSI) and Heat Strain Score Index (HSSI) questionnaires were completed by the workers. Data were analyzed after inter to SPSS16 software. Results: All of the WBGT values were higher than occupational exposure limit. The mean and standard deviation (SD) of the work heart rate in the case and control groups, was equal to 111.1 ± 7.6 beats per minute (bpm) and 114.3 ± 7.9 bpm respectively (P < 0.05). Also the average and SD of the oral temperature in the case and control groups, respectively, was equal to 36.36 ± 0.41 and 36.37 ± 0.55. There was no statistically significant difference. Mean and SD of Physiological Strain Index (PSI), in case and control groups, were 2.53 ± 0.66 and 3.64 ± 0.81, respectively. The mean and SD of the PeSI and the HSSI in the case group were 4.64 ± 0.79 and 10.12 ± 1.71, respectively, and in the control group, 6.41 ± 0.85 and 15.88 ± 0.1.43. Statistically, the difference between PSI, PeSI, and HSSI means was significant. Conclusions: This study results showed that hot environmental conditions were stressful for construction workers and also Iranian evaporative cooling vests (Hifitcool brand) were able to reduce perceptual and physiological heat strain in construction workers in the hot conditions.

The advancement of telecommunication technology is vital for our wireless connectivity and networking across the world, but not at the expense of the lives of other organisms because their extinction follows us. This review article highlighted the various communication systems and technologies implemented and their implications. The relevant keywords used for this review, including fifth generation (5G), electromagnetic radiation (EMR), telephone tower, 5G impacts on lives, 5G impacts on human health, animals, and birds, were used for inclusive search on trustworthy citation databases listed in Scopus, PubMed, Web of Science, and Google Scholar from 1993 to 2022. The findings revealed that the radiations range between radio frequency and electromagnetic frequency is causing detrimental effects on different species including their fertility and fetus development. Experts reported that birds use the earth's EMR to navigate in their flight, but when they are exposed to weak or microwave radiation from the telecommunication towers, they deviate from their path, confused, and even die from telephone tower collisions. The new movement in protecting the bird population from EMR is creating an awareness of "air as a habitat" for birds, and research reports show that it is experimentally proven, that such radiations affect the birds' lives in many ways. Authors believe that these critical surveillance data would create awareness among the readers and researchers about the consequences to human health due to the extensive use of new generation telecommunication and networking technologies. The World Health Organization mentioned the harmful effects of EMR in their report. It shows that a diffuse collection of symptoms such as headaches, anxiety, suicide and depression, nausea, fatigue, and loss of libido may be caused due to low levels of exposure to EMR at home.

Aim: This article evaluates the health risk of occupational exposure to BTEX compounds, cancer risk, and noncancer risk analysis among gas station workers. Materials and Methods: This cross-sectional research evaluates pollutants rank of risk released at Ahvaz stations in Iran. We have collected 96 samples of workers exposed to BTEX and eight samples for control in the ambient air. The National Institute for Occupational Safety and Health (NIOSH) recommended BTEX method numbers 1500 and 1501 for sampling and analysis. To evaluate the risk assessment of pollutants, we utilized a semi-quantitative method offered by Singapore's Occupational Safety and Health Division. Results: The average benzene concentration in the operators' breathing zone (1.202 0.83 ppm) was greater than the threshold limit values-time weighted average (TLVs-TWA) (P < 0.05). Other contaminants had concentrations that were lower than the ACGIH's TLV-TWA (P < 0.05). In gas stations, benzene has a very high danger ranking among chemical compounds. Toluene, ethyl benzene, and xylene in the employees' breathing zone posed a modest risk. The average cancer risk for benzene-exposed operators, head shift workers, and supervisors was calculated to be 4.46 × 10⁻³, 2.90 × 10⁻³, and 2.08 × 10⁻³, respectively. The risk of cancer is projected to be higher than the tolerable level of 10-6. Conclusion: In unique, long-term exposure to benzene has been linked to an increased risk of cancer and toxic effects, and a health-risk assessment can provide useful information about current workplace contaminants.

Aim: A reliable model for wastewater treatment plants (WWTPs) is essential to provide a tool for predicting their performance and to form a basis for controlling the operation of the process also; this would minimize the operation costs. In recent years, computer-based methods have been applied to many areas of environmental issues. Artificial neural networks (ANNs) and genetic algorithm (GA) techniques could be applied for modeling WWTP processes, owing to their high accuracy, adequacy, and quite promising applications in engineering. Materials and Methods: This study applied multilayer feed forward back propagation neural network and GA to predict and optimize the performance of the second phase of the Isfahan North WWTP. Experimental results, which demonstrated the performance of the plant over 6 years were applied for modeling. Results: A three-layer neural network was developed as a predictive model and the network was trained with Levenberg–Marquardt algorithm. The chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS), total kjeldahl nitrogen (TKN), and total phosphorus (TP) were introduced as the model input and output. Neural network performance was evaluated with correlation coefficient ® and least mean square error. Proposed model demonstrated the high consistency of the results of modeling and experiments. GA achieved the best value of input parameters as 324.36, 457.37, 359.11, 60.09, and 14.15 mg/l for BOD, COD, TSS, TKN, TP, respectively. Conclusion: ANN and GA combination provides powerful analysis tool for modeling and optimization of nonlinear relationships between the parameters in WWTPs and could be used for proper design and operation of the WWTPs.

Aim: Protection against nuclear radiation is one of the most important issues in nuclear technology and industries that use this technology. Among the types of radiation emitted from radioactive sources, neutron and gamma rays are among the most dangerous radiations due to lack of electrical charge and serious damage to living tissues. The principal challenge in radiation protection is the proper design of a shield against neutron and gamma radiations. Hence, this study has investigated the improvement of the protection against these radiations. Materials and Methods: This study is of applied-developmental and quantitative type. Calculations have been performed using the MCNPX code in this study, which is one of the strongest nuclear calculation codes. The data were analyzed using quantitative statistics and ORIGIN software (OriginLab company, 1992, Northampton, Massachusetts, USA). Results: Based on the results, utilizing the spherical geometry had a better performance to increase the neutron fluxes in comparison with the cylindrical and cubic geometries. Moreover, polyethylene with high density was selected as the best moderator. Ultimately, it was dealt with the comparison and selection of the best protection to minimize the produced gamma rays due to the absorption of neutrons in different materials used by the source and neutrons that run away from the outer surface of the source configuration. Conclusion: Using the composite sphere of paraffin and polyethylene with high density up to a radius of 12 cm and tungsten with a thickness of 1 cm was suggested as the final configuration for the aim of this study. In comparison to the no-protection mode, this protection is effective to 74% in reducing the neuron dosage and 55% in reducing the primary gamma-ray, while the mentioned protection is about 72%–73% effective in reducing the general dose.

Aim: Hydatid cyst is the Echinococcus granulosus larvae stage and is responsible for echinococcosis. Anticancer effects of hydatid cyst have been shown in human population, experimental animals, and in vitro works. However, the mechanisms of this anticancer activity are not clarified. Hence, in this work, the effect of antisera raised against hydatid cyst antigens on the growth of breast cancer cells has been investigated. Materials and Methods: In this experimental study, the various hydatid cyst antigens were prepared. To raise antisera, each of the hydatid cyst antigens (hydatid cyst fluid, germinal and laminated, protoscolex, and excretory-secretory [ES]) and toxoplasma trophozoite were injections to rabbits. The production of specific antibodies in rabbits determinate by enzyme-linked immunoassay, and then, the rabbit's blood was taken, and their sera isolated under the hood in sterile conditions. Before use, all antisera were inactivated at 56°C for half an hour and also placed under ultraviolet light for 20 min to disinfect. Breast cancer cells in the culture medium were purchased from the Pasteur Institute of Iran and growth in CO2 incubator in the Roswell Park Memorial Institute (RPMI) medium. After appropriate, the cells were counted and divided equally in eight-cell culture flasks and treated with different antisera of hydatid cyst. After 32-h incubation, the number of live cells was counted by trypan blue methods and compared with control groups. Results: Based on the results of this research, the difference between the number of live cells after treatment with antisera against hydatid cyst fluid, toxoplasma trophozoite, and ES antigen was significantly different from number of cells in flask treated with normal rabbit serum. Conclusion: In conclusion, due to the presence of common antigens between parasites and cancer, probably antibodies produced against hydatid cyst antigens may affect the growth of cells in the culture media.

Aim: Safe driving is influenced by various factors, including the driver's level of cognitive performance and thermal comfort. The aim of this study was to investigate temperature indicators, thermal comfort, and mental function parameters among taxi drivers in winter. Methods: This cross-sectional study was performed on 30 taxi drivers in the morning and evening (8–9AM, 4–6PM). In this study, temperature parameters, including dry-bulb temperature and relative humidity, thermal comfort indices, demographic parameters and cognitive performance parameters, including accuracy, work speed, attention, number of errors, mental fatigue, concentration skills, and auditory short-term memory, were measured. Statistical analyzes were performed using SPSS version 26. Results: The average dry-bulb temperature and relative humidity inside the cabin in the morning and evening were 23.2%, 22.1%, 22.3%, and 21.3%, respectively. The results showed that the drivers' dissatisfaction with the temperature in the morning and evening shifts was 6% and 5.6%, respectively. There was no statistically significant difference in the measured parameters in the morning and evening shifts (P > 0.05). The results showed that there was a significant relationship between age and some cognitive function parameters (P < 0.05). Conclusion: More than 90% of drivers feel comfortable when the average dry bulb temperature of 22%–23% can be used to adjust the optimal temperature of the cabin vehicle in winter. Age is an effective factor in the cognitive performance of drivers and the cognitive performance of the drivers was not in a favorable condition, which requires further study to investigate the causes of this issue.

Aim: A high error rate among laboratory staff leads to accidents. This study aimed to investigate the effect of gender, work experience, age, and job stress on the number of errors and work speed in laboratory employees. Materials and Methods: This cross-sectional study was performed on 32 laboratory staff via census method. The instruments used in this study were the General Health Questionnaire Mental Health Questionnaire, demographic questionnaire capturing age, gender, work experience, and level of education, and Health and Safety Executive Job Stress Questionnaire in England. A precision targeting vibrometer was used to measure the speed and number of errors. Independent t-test and Mann–Whitney U-test as well as Pearson's and Spearman's correlation coefficients were used to evaluate the relationship between the parameters using SPSS software version 26. Results: The mean and standard deviation of age, work experience, and job stress were 43.56 ± 7.80 years, 205.68 ± 107.43 months, and 132.59 ± 12.55, respectively. Furthermore, the mean and standard deviation of the number of errors and work speed were 4.90 ± 4.09 and 14.27 ± 5.84, respectively. A significant positive correlation was found between age and the number of errors. Conclusion: The results indicated that gender, work experience, and job stress do not affect the number of errors and work speed in laboratory staff, but age affects the number of errors in employees, and the number of errors increases with age. Explaining the factors affecting the accuracy and speed of staff in the laboratory can lead to use of appropriate manpower and ultimately enhance productivity and reduce accidents in laboratories.

Aim: The present study aims to design, manufacture, and evaluate the performance of an active liquid cooling vest (ALCV) to control the heat strain in hot laboratory conditions. Materials and Methods: An ALCV was designed with a cold liquid circulation system in tubes embedded inside the vest. A performance of ALCV in the hot laboratory conditions with an average temperature of 38.5°C and relative humidity of 40% was done with ALCV and none-ALCV (NALCV). Parameters such as heart rate, oral temperature (OT), thermal sensation (TS), perceived exertion (PE), and chest temperature (CT), forehead temperature (FT), and scapula temperature (ST) were measured. Paired t-test was used to compare the average of the data. Results: The results illustrated that the difference between the average temperature of the ST and CT with ALCV and NALCV, it was 2°C ± 0.5°C. There was a statistically significant difference between the average PE and TS in two testing conditions (P < 0.05). Paired t-test showed that there is no significant difference between the average FT and OT in the two testing conditions (P > 0.05). Conclusion: Due to the positive effects of the designed ALCV in reducing skin temperature, heat sensation, and PE, this cooling vest can be used as a useful and cost-effective solution to reduce the level of heat strain in hot environments.

Aim: The aim of this study was to investigate the knowledge and attitude of the staff of a university of medical sciences about housing health in Kermanshah, Iran. Materials and Methods: For this cross-sectional descriptive-analytical study, based on Morgan Table 100 people were randomly selected and knowledge and attitudes about housing health were assessed based on a researcher-made questionnaire in 2017. The obtained data were analyzed using SPSS software version 18 and paired t-test on Likert scale. Results: A total of 100 employees were studied, more than half of them (60%) were female and more in the group of 20–29 years. The mean scores of knowledge and attitude of the target group regarding housing health were 18.35 and 78.00, respectively. The mean score of knowledge in men and women is significantly different (P < 0.001). However, the attitude scores of the two groups were not statistically significant (P = 0.15). Although knowledge of housing quality was reasonable among respondents, the method of disposing of sanitary waste and housing maintenance was poor. The highest score of women's attitude was related to the groups with diploma and/or associate degree and the highest score of knowledge and attitude in men was related to the groups with bachelor's degree or higher. Conclusion: This study showed that people with higher education have better knowledge and attitudes about housing health than people with lower education. However, more research is needed to fully understand the link between housing and adverse health outcomes.

Aim: This study aimed to determine the medical staff's burnout level and its related factors at Daran Shahid Rajaee Hospital. Materials and Methods: The total number of participants was 145 medical staff who participated in this cross-sectional study. Data were collected employing such various instruments as demographic information questionnaires, general health questionnaires, job satisfaction (JS), and Maslach burnout inventory. Then, the researcher analyzed the data with correlation, t-tests, and variance by using the SPSS software version 26. Results: The findings indicated that 79% of the medical staff suffer from high burnout level. The results showed that the correlation between burnout levels and JS was statistically significant (P < 0.001). Moreover, the correlation of depersonalization levels with marital status, age, work experience, and type of employment was significant (P < 0.001) as well. Conclusion: The results indicated that, during the pandemic of COVID-19, the medical staff's burnout was at a high level. Interestingly, on the emotional exhaustion scale, the medical staff burnout was more than other burnout levels requiring organizational interventions to lessen medical staff burnout.

Aim: The purpose of this article is to analyze subjective self-evaluation of thermal and respiratory discomfort experienced by workers in the foundry industry. Materials and Methods: One hundred and sixty-one workers aged 18–55 years participated in this study. Discomfort due to high temperatures, hot work, skin rashes, cramps, fatigue, weakness, respiratory problems, and inhalation was subjectively evaluated by the questionnaire survey. The questionnaire is validated, and Cronbach's alpha test and Kaiser–Meyer–Olkin's test are applied to ensure data reliability and adequacy. Results: The results indicated that the highest and lowest percentage of workers experiencing at least one discomfort is 86% and 4%, respectively. Furthermore, 11 out of 19 discomfort factors scored above the average thermal and respiratory discomfort score of 2.5 on the scale of 5. Conclusion: According to this study outcome, more exploration is needed on the relationship among thermal and respiratory discomfort and its effect on the workers in the foundry environment.

Aim: Today, low back pain (LBP) is one of the major challenges among occupational health professionals in various jobs. The objective of this study was to investigate the relation between work limitation and functional disability with LBP in Iranian nurses. Materials and Methods: Overall, 400 subjects were examined systematic random sampling in this cross-sectional-comparative study. Participants were divided into the case (195 persons with LBP) and control (205 persons without LBP) groups. Data were collected using a comprehensive questionnaire including demographic information form, Nordic Musculoskeletal Questionnaire, Oswestry Disability Questionnaire, and Work Limitation Questionnaire. The collected data analyzed using SPSS statistical software version 20. Results: Findings showed that age, marital status, and family history were significantly associated with LBP (P < 0.001). The most common cause of back pain among nurses was work-related LBP (56.9%) and genetics (heredity) (30.2%). Furthermore, the mean score of functional disability and work limitation in the case group was higher than the control group (P < 0.001). Conclusion: Although, based on statistical analyzes, the frequency distribution and mean score of functional disability, work limitation, and all subscales in the group with LBP were higher than the group without LBP, it seems that back pain does not put nurses in working functional disruptive conditions.

Aim: In dental clinic environment, dental staff and patients are daily exposed to many types of infectious agents transported by aerosols and droplets, promoting an increased risk of cross infection. The aim of this study was to assess the level of bacterial contamination of air and surfaces in different wards of the educational clinic in Arak University of Medical Sciences. Materials and Methods: Samples were obtained from the air and surfaces of five active wards of the dental school clinic. Air sampling was performed actively at ½ and 2 m distances from two random units in each ward. Sampling from surfaces was conducted using a wet sterile swab from the washing sink and handpiece after disinfection. Grown colonies were counted and bacterial phenotyping was based primarily on morphology, Gram-staining, endospore formation, catalase activity, and cytochrome oxidase presence. For statistical analysis, the Kruskal–Wallis test was used at a significance level of P < 0.05. Results: Bacterial contamination was detected in all of 80 samples taken from the surfaces of different sections. Regarding the total number of colonies growing from surface samples, there was no significant difference between the studied wards (P > 0.05). The mean concentration of airborne bacteria in the pediatric ward (488 CFU/m³) at a distance of 0.5 m and the surgical ward (339 CFU/m³) at a distance of 2 m had the highest value compared to other wards. In general, there was no statistically significant difference between the total density of airborne bacteria at distances of 0.5 and 2 m (P > 0.05). Conclusion: Bacterial contamination in the environment of the dentistry clinic increases during the treatment process. The clinic's space, the types of the ward and treatment process, and distance from the unit are among the factors affecting the type and diffusion extent of microbial aerosols.

Aim: Microplastics (MPs) have become an emerging environmental contaminant and there are increasing concerns about potentially toxic effects on living organisms. This study is aimed to determine uptake, tissue accumulation, and toxic effects of polyurethane microplastics (PUR-MPs) on zebra fish. Materials and Methods: The zebra fish were exposed to different concentrations of PURs-MPs of different sizes for 10 days. Mortality and behavioral changes were monitored. Ingestion and tissue accumulation of PUR-MPs were studied by fluorescent tagging of PUR-MPs. Pathological damages of tissues were investigated with hematoxylin-eosin staining. Results: Microsize PUR-MPs can be ingested by zebra fish and fluorescent-tagged PUR-MPs were found in gills and gastrointestinal (GI) tract of fish after 10 days of exposure. A significant negative correlation was found between fluorescence intensity in fish tissues and size of PUR-MPs. Gills, GI tract, and liver were the most affected tissues by PUR-MP toxicity. GI damages included epithelial detachment, thinning of the bowel wall, congestive inflammation, epithelial damage, and lesions of villi in the gastric wall. Necrosis, adhesion, and partial fusion of secondary lamellae were the dominant pathological damages in the gills. Liver also was affected by cellular necrosis, infiltration, and lipid droplets. Conclusion: Exposure of zebra fish to PUR-MPs leads to ingestion of these particles by fish and significant increase in fish mortality and tissue damages. Particle size and MP concentration were the key determinant factors in PUR-MP toxicity. The results of the present study provide novel insights into environmental toxicity of PUR-MPs and toxic effect of PUR-MPs in aquatic organisms.

Aims: This study aimed to investigate the level of citizen participation in solid waste recycling in the Isfahan metropolis. Materials and Methods: To assess the proportionate rate of citizen participation in 15 districts of the city, 400 questionnaires were filled out by participants through stratified random sampling method. The statistical analysis (Correlation and regression analysis) of the data was performed using the SPSS software. Results: The results showed that despite popular belief, the situation of solid waste recycling in Isfahan is unfavorable. Moreover, the highest level of citizen participation is related to district 10 (29.91%) and the lowest amount is associated with district 5 (12.22%). Applying strategies tailored to the social, economical, and cultural characteristics of each district and based on the current level of participation of citizens in each district can improve the current status. Conclusion: The results showed that the citizens need more education to increase their participation in Comprehensive Waste management. However, the provision of educational programs through mass media along with municipality co-operation leads to elevate the people awareness.

Aim: In this study, the microplastic (MP) concentration in several brands of salts was investigated. Materials and Methods: Fifteen samples of crystallized salt, refined sea salt, unrefined sea salt, and rock salt were purchased from local markets and analyzed for MPs concentration. The salts were digested with the Catalytic Wet Peroxide Oxidation method first, and the MPs were floated based on density difference. Then, MPs were counted by scanning electron microscopy and nature was confirmed by using micro-Raman spectroscopy. Results: The MP concentrations in crystallized salt, refined sea salt, unrefined sea salt, and rock salt were 151.4 ± 48.8, 406.7 ± 93.3, 1417.4 ± 203.3, and 283.4 ± 97.0 MPs/kg, respectively. The most abundant polymers were polyethylene, polypropylene, and polyethylene terephthalate. The fiber was the dominant shape of MPs in all salt samples. Conclusions: This study reveals the presence of MPs in crystallized salt, refined sea salt, unrefined sea salt, and rock salt. Therefore, the consumption of salts can expose humans to MPs.

Aim: Estrogenic compounds as a group of endocrine disruptive compounds can interfere with endocrine system beings. In the present work, an attempt has been made, to characterize the kinetic coefficients of natural and synthetic estrogens, in a pilot-scale moving bed biofilm bioreactor (MBBR). Materials and Methods: The substrate removal rates were investigated at different organic loading rates, and hydraulic retention times. By applying some biokinetic models including first order, second order, Stover–Kincannon, and the Monod equation, the kinetic constants (m, Ks, k, Y, and Kd) were determined. Results: Estrogen-specific removal rate was between 0.22 and 1.45 μg. g VSS-1.d-1 for natural and synthetic hormones. The experimental data showed that the Stover–Kincannon model and second-order model were the fit models and have high correlation coefficients more than 99%. Conclusion: These findings indicated that theses mathematical models could be promising models for effectively predicting kinetic parameters for performance of MBBR reactors.

Aim: Although vermicomposting is rich in nutrients, the virulent microbes and pathogens present in it may be a threat to human health and the environment. Therefore, the objective of this study is to investigate the microbial quality of produced vermicompost, including fecal coliform and parasitic eggs, at a pilot scale, and compare it to present standards. Materials and Methods: Three various reactors containing decomposable domestic waste (T1), cow manure (T2), and dewatered sludge (T3) were used to produce vermicompost using Eisenia fetida. According to the standard methods, fecal coliforms, parasitic eggs, and some of the treatment characteristics including organic carbons, nitrogen, temperature, humidity, pH, electrical conductivity and metals were evaluated during the 56-day operation period. Results: According to the results, the number of fecal coliforms in treatments of T1, T2 and T3 reduced from 2.5 × 10⁴, 6 × 10⁵ and 15 × 10⁶ to 1000, 1500 and 1500 MPN/g dw, respectively. All parasite eggs reached zero after the 3^rd week. At the end of the study, the average of organic carbon in T1, T2, and T3 were 35.4 ± 6%, 50.7 ± 5%, and 58.4 ± 7%, respectively. This value for total nitrogen were 0.9 ± 0.2%, 1.8 ± 0.7%, and 4.2 ± 1.2%, respectively. Conclusion: Results showed that the worm E. fetida has a great ability to reduce pathogens without the need for an increase in temperature. Furthermore, it can be concluded that vermicompost can improve the quality of compost in 8 weeks. The vermicomposting process can also greatly destroy the fecal coliforms and all parasite eggs.

Aim: The aim of this study is to determine the benzene, toluene, ethylbenzene, and xylene (BTEX) concentration levels in and around the fuel station and its harmful health effects in the city of Dammam and Al Khobar, Saudi Arabia. Materials and Methods: Forty fuel-dispensing facilities were randomly selected on the basis of three different areas: residential, traffic intersection, and petrol pump locations (refueling stations). Samples were collected using coconut shell charcoal cartridges, and the portable ambient analyzer was used for measuring BTEX concentration. Results: Results shows that the average concentration of BTEX levels around fuel stations was 10.30, 4.09, and 2.47 ppm, respectively. All mean concentration values of BTEX around residential, traffic intersection, and fuel stations are exceeding the limits of air quality standards values (P < 0.01). The mean concentration of BTEX around the residential area, side street, and direct street was as follows: benzene 8, 12.2, and 11.5 ppm; toluene 2.5, 5.95, and 3.37 ppm; and xylene 2, 2.13, and 2.7 ppm. Hazard quotient was >1, which showed that carcinogenic probability has increased those exposed to this toxic chemical. Conclusion: Values for BTEX were greater than those found in the neighboring residential area of the city and even 100 m away from the fuel station which can have a negative impact on the health of several residences. The environmental contamination associated with BTEX in petrol fuel stations impulses the necessity of preventive programs to reduce further air quality deterioration and reduce the harmful health effects.

Aims: The Iranian city of Sari with a green nature has great environmental importance, especially in ecotourism. Thus, the proper management of medical wastes is necessary to maintain a sustainable environment. This study is aimed to determine the quantitative and qualitative wastes in the hospitals of Sari. Materials and Methods: This was a cross-sectional study using a descriptive-analytical approach to analyze the infectious and noninfectious wastes of four hospitals in Sari. The data collection instrument was a checklist that was completed on visits to hospitals and observation of cases. Data analysis was performed using Excel and R software programs. Results: The average quantity of the total waste produced in hospitals was 218, 482, 19.5, and 17 kg/day for infectious, household, sharp-cutter, and pharmaceutical wastes, respectively. The rate of hospital waste production for various types of infectious, household, sharp-cutter, and pharmaceutical wastes equaled 1.15, 2.13, 0.09, and 0.28 kg/bed, respectively. Conclusion: Due to the high percentage of infectious wastes, despite considerable efforts to separate wastes, there are still problems in the hospitals that require more attention from the authorities, as well as the incorporation of new methods to render waste safe before it leaves the hospital.

Aim: In this study, the presence of four phthalate esters, including diethyl phthalate (DEP), Dibutyl phthalate, benzyl butyl phthalate (BBP), and diethylhexyl phthalate (DEHP) in pasteurized milk with plastic packages was investigated during the time allowed for consumption. Materials and Methods: The pasteurized milk samples, including 7 high-consumed brands, were purchased from reputable stores and two factories in Isfahan in 2019. The concentration of phthalate esters was measured by gas chromatography-mass spectroscopy paired with dispersive liquid-liquid microextraction. Results: According to the results of this study, among the analyzed samples of stores, DEHP (0.25 μg/l) and BBP (0.25 μg/l) had the highest mean concentrations in pasteurized milk, respectively. The analyzed results of the factories showed a high BBP of 0.1 μg/l. Among the studied brands, the highest concentration of phthalate esters was 0.42 μg/l. The mean concentrations obtained in this study were lower than the international standards set. Conclusion: Due to the low average concentration of phthalate esters in pasteurized milk, consumption of these products has no serious risk for humans and the share of pasteurized milk in terms of the presence of phthalate esters is negligible.

Aim: Low-frequency sounds are generated from many sources in both the occupational and nonoccupational environments. Hence, the aim of this study was to investigate the effect of low-frequency noise (LFN) on the working speed and the rate of annoyance of the subjects under study. Materials and Methods: This cross-sectional/interventional study was performed in the sound and vibration laboratory of Isfahan University of Medical Sciences in 2019. Simple random sampling was used to select the subjects. In this study, the working speed of the subjects was evaluated using mental arithmetic test and the rate of the perceived annoyance was measured using ISO 15666 in Likert format (0–11) due to exposure to noise sources. Mann–Whitney U-test was used to analyze the data. Results: There was a significant statistical difference in the rate of the individuals' working speed Between 0 and 90 min at the frequency of 125 Hz and the sound level of 95 dB (P = 0.029). There was a statistically significant difference between the frequencies of 125 and 1000 Hz at the sound pressure level of 85 dB and the 45 min time (P = 0.001) and 90 min (P = 0.001) as well as at the 95 dB sound pressure level at 45 min (P = 001) and 90 min (P = 0.001). Conclusion: The results of the present study showed that increasing sound pressure levels and the exposure time in both LFN and high-frequency noises, increased the working speed and the amount of perceived annoyance in individuals.

Aim: In this study, the levels of indoor and outdoor (I/O) airborne particles and bioaerosols were assessed in two primary schools. Simultaneously, I/O microbial airborne and particle matter (PM) concentrations were analyzed during the autumn of 2018. Materials and Methods: A total of 96 I/O air samples were taken by using a single-stage Andersen sampler from two selected primary schools located in Arak, Iran. Simultaneous with sampling, PM₁₀ and PM_2.5 concentrations, temperature, and relative humidity were also measured. Results: The results indicated that the mean levels of indoor airborne bacteria and fungi were 448 and 94 CFU/m³, respectively. The I/O ratios of bacteria and fungi were 2.1 and 0.7, respectively. The airborne bacteria levels showed a weak-positive and moderate-positive association with PM_2.5 (r = 0.28, P < 0.05) and PM₁₀ (r = 0.32, P < 0.05), respectively. Further, a moderate-positive association was observed between indoor fungi and the PM_2.5 (r = 0.46, P < 0.05) and PM₁₀ (r = 0.30, P < 0.05). In our study, the most fungal species identified were Penicillium, Cladosporium, and Aspergillus, and Staphylococcus spp., Micrococcus spp., and Bacillus spp. were the most frequently founded indoor bacteria. Conclusion: Comparative analysis of classrooms in two schools showed that indoor sources and building conditions have a key role in indoor air quality.

Aims: This study aimed to comparatively investigate the efficiency of removal of formaldehyde using advanced oxidation process ultraviolet (UV)/S₂O₈^2-/Fe²⁺ and UV/S₂O₈^2- from aqueous solutions. Materials and Methods: In this experimental-laboratory study, the UV/S₂O₈² and UV/S₂O₈^2-/Fe²⁺ processes were used to remove formaldehyde. UV radiation was provided by a low pressure (6 W) UV lamp. Effects of various factors including pH, different irradiation durations, different concentrations of iron ions, initial concentration formaldehyde, and persulfate concentration were evaluated. The remaining formaldehyde concentration in the samples was measured by spectrophotometer at 412 nm wavelength. Results: The results showed that in the UV/S₂O₈^2- method, the formaldehyde removal efficiency decreased with increasing pH from 3 to 9, while in the UV/S₂O₈^2-/Fe²⁺ method, the formaldehyde removal efficiency increased with increasing pH and concentrations of iron ion. In both methods, as the initial concentration of formaldehyde was increased, its removal efficiency decreased, and the highest formaldehyde removal rate was obtained in UV/S₂O₈^2- method at persulfate concentration of 100 mM. However, in the UV/S₂O₈^2-/Fe²⁺ method, the removal efficiency decreased with increasing concentration of persulfate to 100 mM. Conclusion: The results showed that the UV/S₂O8^2-/Fe²⁺ process was more efficient (87.57%) to remove formaldehyde at high concentrations. Therefore, it is recommended to study the efficiency of this process as one of the clean and environmentally friendly methods at full scale for real wastewater.

Aims: This study was aimed to discriminate ion aflatoxin B₁(AFB₁) contamination of pistachio kernels after/E-beam irradiation. Materials and Methods: Pistachios were inoculated with known concentrations of Aspergillus flavus. Then pistachio samples were exposed to E-beam at five different doses (0, 1, 3, 5, and 7 kGy) and in various storage times (0, 30, 60, 90, and 180 days) at ambient temperature. Then, sensorial characteristics, fungal, and AFB₁ contamination of pistachio kernels were investigated. Statistical analysis was performed using the SPSS software version 22. by using descriptive statistics, Kolmogorov-Smirnov, and Kruskal–Wallis tests. Results: The mean percentage reduction of aflatoxin in the treated samples at doses of 1, 3, 5, and 7 kGy on different days of storage with two replicates was 38.84%, 48.79%, 53.50%, and 77.17%, respectively. The dose of 1 kGy was found to be appropriate in reducing the number of mold in pistachios without having any change in their organoleptic properties. The organoleptic properties, including color, texture, and overall palatability of pistachios, significantly changed after a dose of 5 kGy. Conclusion: Electron-beam (E-beam) efficiency against A. flavus and aflatoxin degradation increased with increasing radiation dose. Due to the sensitivity of A. flavus to radiation, this method can be used to improve the quality of pistachio products.

Aim: The aim of this study was to reduce the amount of diazinon from aqueous media using chemical–thermal-activated watermelon rind. Materials and Methods: This experimental study was carried out in a laboratory. First, watermelon rind was activated by chemical–thermal method. Then, the effective parameters of the diazinon adsorption process, including the initial concentration of diazinon (0.17–1 μg/L), pH (3–10), adsorbent amount (0.05–1 g/l), and contact time (30–100 min), were investigated and optimized. The amount of residual diazinon was measured by high-performance liquid chromatography. In this study, Taguchi method was used to determine the sample size and statistical analysis. Furthermore, in this study, to describe the adsorption equilibrium, Freundlich and Langmuir isotherm models were used. Results: The results showed that under an optimal pH of 6, the equilibrium time of 30 min, the amount of adsorbent 1 g/L, and the initial concentration 0.17 μg/L, the elimination efficiency of diazinon was 95.1%. Furthermore, the results of isothermic studies have shown that the removal of diazinon follows the Freundlich model (R² = 0.921). Conclusion: Chemical–thermal-activated watermelon rind can effectively be used to remove low concentrations of diazinon from aqueous solutions.

Aim: This study is aimed to determine the disinfectant activity of Derdevice plus Y^® and I&D Sept^® against carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates. Materials and Methods: The bactericidal activity of Derdevice plus Y^® and I&D Sept^® were tested in vitro under clean and dirty conditions by a quantitative suspension test according to EN 13727. The effectiveness of the disinfectants was compared with 10% sodium hypochlorite (NaOCl), 7% benzalkonium chloride (BC), 2% chlorhexidine digluconate (CHX), and 70% ethyl alcohol (EtOH). After 1, 5, and 60 min of contact with the biocides, the colony-forming units were counted, and the logarithmic reduction factor was determined. Results: A dilution of 1/300 of Derdevice plus Y^® disinfectant showed bactericidal activity against clinical isolates and standard strains (growth reduction was =5 log₁₀) after 5 and 60 min contact times and under clean and dirty conditions. A 100% concentration of I&D Sept^® showed a bactericidal effect within the contact time (60 min) under clean and dirty conditions with the reductions of =5 log₁₀ and =3 log₁₀, respectively. Standard biocides such as BC, CHX, NaOCl, and EtOH showed marked effects after various contact times and the conditions onto tested strains. Conclusions: The results of our study confirm that the biocides of Derdevice plus Y® and I&D Sept^® used in our hospital were found to be effective against K. pneumoniae isolates.

Aims: Nitrate can enter water bodies through using chemical fertilizers and discharging the effluents from municipal and industrial sewage treatment plants. As a superiority to the conventional statistical models, Grey models (GMs) require only a limited amount of representative data to estimate the behavior of unknown systems. In the current study, the nitrate concentration of the year 2023 in Babol groundwater resources was forecasted by using GM, namely GM (1, 1). Materials and Methods: This descriptive-cross-sectional study was performed in the city of Babol. The data of 63 wells in urban and rural areas during the warm and cold seasons between 2007 and 2017 were supplied from the Health Center and Babol Rural Water and Sewage Company. In data set, the observed values between 2007 and 2015 were used to fit models, and the observed values between 2016 and 2017 were used to evaluate the accuracy of the model's predictions. To assess the efficiency of the model fitted and precision of the predicted values, we used indexes of forecast absolute error, small error probability, and the proportion of variance statistical metrics. Results: Simulated results showed that the accuracy of the model GM (1, 1) to predict and forecast both data sets is entirely appropriate and reliable. The forecasting values of nitrate concentration of the year 2023 and 8 years later, for urban and rural areas in warm and cold seasons, are 21.30 and 7.30 and 15.63 and 5.34 mg/L, respectively. Conclusion: Although the predicted concentration of nitrate in the studied area is lower than that the standard concentration suggested by the World Health Organization, all water resources should be protected effectively.

Aim: This study was conducted on the microbial contamination of water of Bandar Abbas beaches in order to achieve comprehensive information for determining the quality of swimming coasts. Materials and Methods: After initial examination of the number and location of swimming coasts in terms of appearance and areas with the highest number of swimmers, 5 coastal swimming areas were selected as sampling sites. Sampling was done for 6 months and 10 samples per month. Physicochemical (water temperature, pH, turbidity, electrical conductivity, and salinity) and microbial indicators including total and fecal coliforms, Escherichia coli, fecal streptococci, Clostridium perfringens as well as Salmonella as a pathogenic microorganism were measured in each sampling period. Results: Results of this study showed that the mean number of streptococci, total coliforms, fecal coliforms, and E. coli was 930, 24,000, 9300, and 9300 most probable number (MPN)/100 ml, respectively. It was also found that the mean concentration of C. perfringens in the sampling stations was 250 CFU/100 ml. The frequency of detection of Salmonella in stations 2 and 3 was 16.7% and in station 5 was 8.3% and was not observed in other stations. According to the results, in most sampling stations, the concentration of the microbial indicators was higher than the standard. A significant relationship between different species of bacteria was observed. The results also showed a significant relationship between the amount of turbidity and microbial (P < 0.05). Conclusion: According to the results of the present study, it was observed that most of the swimming coasts of Bandar Abbas were not in a favorable microbial condition, due to the discharge of industrial and municipal sewage and waste disposal. The results highlight the potential risk of microbial pathogens for swimmers and the necessity of sanitation practices of coastal area to protect public health.

Aims: This study was aimed at the evaluation of heavy metals in the drinking water of the rural area of Divandarreh city and the assessment of carcinogenic and non-carcinogenic health risks. Materials and Methods: In the present work, concentration of four heavy metals in drinking water resource in the rural area of Divandarreh County were evaluated. For these aim, the numbers of 29 samples were collected from rural drinking water resources, and the concentration of heavy metals was determined. In addition, carcinogenic and noncarcinogenic risk assessment was conducted in children and adults as target groups. Results: The level of Cd was higher than the WHO drinking water Standard. The average amount of target hazard quotient for heavy metals through ingestion in children and adults were in the order of Cd > Cr > Pb > Ni. The total hazard quotient hazard quotients (HQ ing + HQ derm) in children group was higher than the limit set by the USEPA (hazard index = 1.68), indicating probable noncarcinogenic risk to this group through consumption of water. Conclusion: Based on the obtained data, the carcinogenic risk for all of the heavy metals were higher than the permissible standard. The obtained data can be useful for managers and the water and wastewater department regarding the improvement of drinking water quality.

Aims: Over 5.5 trillion cigarettes are produced annually. Based on the observations, 76% of these consumed cigarettes are littered in public areas instead of discarding in suitable bins. Rainwater drain system carries the water and other wastes such as cigarette butts from the ground and transfers them to the bigger aquatic media without any treatment in which hundreds of chemicals leach into animal's habitats and our water supply origin. The key purpose of this article was to measure the concentration of Arsenic (As) released into water from cigarette butts and to compare their levels among the different brands. Materials and Methods: Ten cigarette butts (comprising cigarette filter and remaining tobacco) of five cigarette brands named Winston, Bahman, Kent, Montana, and Magna were soaked into individual 100 ml of distilled water for 10 days. Five solutions were prepared for each brand, as was detected in all leachate of brands but with different quantities. Results: Arsenic levels were 53.51, 32.78, 55.33, 42.4, and 59.24 μg/l for Kent, Winston, Montana, Bahman, and Magna, respectively. Conclusion: As concentrations were placed in the following order: Winston < Bahman < Kent, Montana, Magna. Based on the present study, cigarette butt plays an important role in environmental pollution and its importance should not be ignored in terms of arsenic potential.

Aims: This survey aimed to investigate the impact of common storage conditions on the migration of phthalate esters (PEs) including di-2-(ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), terephthalic acid (TPA), and phthalic anhydride from polyethylene terephthalate (PET) bottle into the water and to assess the potential human health risk using Monte Carlo simulation (MCS). Materials and Methods: Three different PET-bottled water brands were stored for 7 and 90 days at three temperatures: 5, 25, and >45°C. PEs were extracted from samples using the solid-phase extraction method with gas chromatography–mass spectrometry. Results: The highest concentrations were found for TPA in samples immediately after purchasing. DEHP and DBP were identified at 90 days in all of the samples. Based on the health risk assessment, the hazard quotient of four compounds in the MCS method was <1; therefore, it should not be considered as a matter of concern. However, excess lifetime cancer risk for DEHP (3.09 × 10⁻⁵) based on the maximum concentration was found to be more than 10⁻⁶. Furthermore, the adverse estrogenic effects of DEHP and DBP appeared to be significant. Conclusion: The probabilistic risk assessment revealed that high estrogen equivalence (DEHP and DBP) seemed to have adverse estrogenic effects on adults. Furthermore, adults were in carcinogenic risk of DEHP. The quality of water bottled in PET may change during the long period, and further research is recommended for the monitoring of phthalates in bottled water to ensure human health.

Aims: This study designed to investigate the concentration of some heavy metals (HM) in the soil of agricultural land of Gonbad-e Kavus in Golestan province and relationship of these metals with esophageal cancer disease. Materials and Methods: For the investigation of pollution, especially HM in the soil, 5 points were randomly selected from each village (3 villages). The samples dried and screened by 200 mesh sieve.Then, the samples were analyzed for HM using ICP/MS. Results: The mean of Cadmium (Cd), Zinc, Cobalt, Chromium, Manganese, Nickel, Arsenic, Copper (Cu), Lead (Pb), and Iron (Fe) in soil was 0.5938 ± 1.7, 74.06 ± 18.9, 12.06 ± 1.28, 68.68 ± 5.85, 627.37 ± 53.3, 38.43 ± 4.4, 6.51 ± 1.21, 29.37 ± 4.3, 17.25 ± 3.5, and 27766.06 ± 2200 mg/kg, respectively. Conclusion: The concentration of metals except Cd and iron was less than the global standards. The concentration of some metals in the soil is almost high due to the high consumption of urea, phosphate, and nitrogen fertilizers. Therefore, it is recommended to educate farmers and use less chemical fertilizers.

Aim: Nosocomial infections have become increasingly a major health concern in many hospitals. Gram-negative bacteria (GNB), including Acinetobacter baumannii, Pseudomonas aeruginosa and Legionella have emerged among the most problematic microorganisms in hospital settings, which can cause a variety of nosocomial infections, especially in susceptible individuals. Biofilm formation allows these waterborne agents to persist in hospital water systems for extended periods. Since the transmission is the initial step in disease occurrence, effective prevention of nosocomial infections requires a better knowledge about waterborne bacteria. The aim of this study was to investigate the frequency of presence of GNB in hospital water systems by a rapid and reliable assay. Materials and Methods: A total of 33 water samples were collected from 11 hospitals of Isfahan University of Medical Sciences, Iran and analyzed for the presence of GNB by a polymerase chain reaction (PCR) assay with the application of specific primer sets. Results: From the 11 hospitals surveyed, 91% (10 of 11) were positive for at least one of the types of GNB. GNB were detected in 58% (19 of 33) of water samples. 45% (15 of 33) of samples were positive for legionella. A. baumannii and P. aeruginosa were detected in 18% (6 of 33) of water samples. The mean concentration of heterotrophic bacteria was 36 CFU/ml. Conclusion: Detection of GNB in hospital water systems with a relatively high frequency revealed that hospital water may act as an important route for transmission of nosocomial infections. The results emphasize the importance of rapid microbiological monitoring and the implementation of strict control measures in hospital water systems.

Aims: Urban expansion has caused lots of problems such as air pollution, which endanger the health of residents. In this research, the spatiotemporal trend of atmospheric fine particulate matter (PM_2.5) of Isfahan was studied and modeled using distributed space–time expectation–maximization (D-STEM) software in 2017. Materials and Methods: This software uses a flexible hierarchical space–time model that can deal with multiple variables and massive loads of missing data. Model estimation is based on the expectation–maximization algorithm. The effects of confounder variables such as holidays, altitude, average temperature and relative humidity, rainfall, wind speed, and direction were considered in the modeling. The hourly measured ambient PM_2.5concentration data were obtained from seven air pollution monitoring stations installed in different zones of Isfahan and operated by the department of environment. Results: The distribution map of the pollutant demonstrated two polluted areas located in southwest and southeast regions of the city that are high traffic and densely populated area. PM_2.5concentration was significantly increased (P < 0.05) with an increase in land elevation by a coefficient of 0.93; conversely, it decreased significantly (P < 0.05) with every increase in wind speed by a coefficient of −0.226. Conclusion: Given the spatiotemporal correlations between air pollutant data, it is necessary to incorporate these correlations into model to obtain more accurate estimates. Using the statistical models and methods to manage the data, time, and volume of calculations in spatiotemporal estimations, the D-STEM program gives more accurate estimates of the desired parameters. Presenting models and maps for every desired time period are another feature of this software that can be useful in health programming and environmental management. Vehicular traffic had a significant effect on the increasing trend of the pollutant level in urban areas; however, the effects of atmospheric phenomena such as dust storms and thermal inversion cannot be ignored.

Aim: This study was conducted to evaluate the effects of ambient concentrations of PM_2.5 and PM₁₀ on the health-related aspects including the total mortality, respiratory and cardiovascular diseases, and hospital admissions due to respiratory and cardiovascular diseases in Karaj, Alborz Province, Iran, during 2012–2016 using the AirQ2.2.3 software. The effects of meteorological parameters on the PM_2.5 and PM₁₀ levels were also investigated. Materials and Methods: Meteorological parameters, population, and the pollutant data were obtained from the Department of Environmental Protection, Karaj (Alborz, Iran). Statistical analysis was performed using the SPSS 24 software to study the relationship between the PM_2.5 and PM₁₀ concentrations and the meteorological parameters. Results: Our results showed a direct relationship between the PM₁₀ concentration and the temperature (r = 0.34, P < 0.018) and relative humidity (r = 0.37, P < 0.5). However, there was a negative relationship between the PM₁₀ concentration with wind speed (r < −0.328, P < 0.014) and precipitation (r < −0.179, P < 0.327). Similarly, there was a direct relationship between the PM_2.5 concentration and the temperature (r = 0.41, P < 0.014) and relative humidity (r = 0.37, P < 0.05). On the other hand, a negative relationship was observed between the PM_2.5 concentration with wind speed (r < −0.138, P < 0.010) and precipitation (r < −0.12, P < 0.201). The total number of death, death due to cardiovascular and respiratory diseases, and hospital admissions due to cardiovascular and respiratory diseases were equal to 1619, 1096, 306, and 4822, respectively. Conclusions: The results of this study showed that the concentrations of PM_2.5 and PM₁₀ should be reduced through applying the management strategies to improve the health of the residents in Karaj city.

Aim: In developing countries, pesticide poisoning, regardless of occupational exposure or deliberate actions, is one of the major public health problems. To determine the impact of occupational exposure to pesticides on workers' health status, this study evaluated the consequences of pesticide exposure and its effects on hematological indices.Materials and Methods: Eighty workers of pesticide production factories were studied in two experimental and control groups during 2018–2020. Data were collected using demographic, occupational, health questionnaires, and blood analysis. The collected data were analyzed using SPSS software (ver. 23), Chi-square, and U Mann–Whitney test considering a significance level of 0.05. Results: The age range of subjects was 23–56 years (mean = 36.21 ± 6.744). A significant difference was observed between studied groups in terms of marital status, education level, and work shift. In addition, levels of erythrocyte sedimentation rate (ESR) (P = 0.036), white blood cell (WBC) (P = 0.009), uric acid (P = 0.033), and alkaline phosphates (P < 0.001) were significantly different between the two studied groups. The results showed a significant difference between the hematology Index level of toxin production workers and workers in administrative and service units. Conclusion: As expected given the type of their job, a significant difference was observed between studied groups in terms of marital status, education level, and work shift, use of safety equipment, as well as residency. Furthermore, levels of ESR, WBC, uric acid, and alkaline phosphates were significantly different. It seems that pesticide toxins exposure in the poison-production industry causes hematological changes, which may be dangerous in a long time.

Aim: Zayandehrood River is an important drinking water source in Isfahan Province which has been exposed to contamination. The high variation of physical and chemical properties of water is an important factor influencing on the consumers' health and the recipient environment. This study aims to access the health and ecological hazards related to water quality-determining parameters. Materials and Methods: In present work, all the existing data on the physical and chemical quality of Zayandehrood water for two years (March 2013 to March 2015) were collected from Isfahan Province Regional Water Company. The collected data are including dissolved oxygen, turbidity, conductivity, nitrate, phosphate, ammonia, and heavy metals such as arsenic and cadmium. The environmental hazard were determined using the contamination indices such as heavy metal pollution index, positive index, and organic pollution index, and health hazards arising from the absorption of chemical parameters were assessed based on the Environmental Protection Agency model and the use of Rural Access Index. Results: The highest noncarcinogenic hazard due to the absorption of chemical parameters was for the children group, and the ratio of health hazard and the probability of exposure to each of the chemical compounds lies in the permissible limit. The hazard higher than 1 revealing the medium hazard was, however, found in the children age group. Assessment of environmental hazards accordingly shows that the quality of the water environment has low contamination. Conclusion: The contamination of Zayandehrood water with chemical compounds can play an important role in diseases due to the exposure of low-quality water. It is thus advised to properly treat water before drinking it, and in order to decrease the concentration of poisonous chemicals in Zayandehrood Lake water, appropriate actions should be taken to conserve it.

Aim: Welding is one of the most common occupations associated with occupational lung disease and is often associated with respiratory symptoms because inhalation is a common way of exposure with welding fume in welders. The aim of this study was to investigate the efficiency and Total Internal Leakage (TIL) valve fabric respiration protection mask made in Iran against different metals in the welding fume. Methods: To determine the efficiency of the mask, the concentration of pollutants in the air outside the mask and the concentration of pollutants in the air inside the mask were measured simultaneously. NIOSH 7302 method was used to sample the air inside and outside of the masks. The elements Al, Cu, Fe, Mn, Ti, and Zn in the welding fume were analyzed. Results: The efficiency of the mask against titanium and iron metals is higher than other metals. The average efficiency of the respiratory mask is 75.46% and the TIL rate is 23.42%. Conclusion: The mask absorbs different metals of welding fumes with different efficiencies. Improving the efficiency of the mask body to create a suitable fit that eliminates or minimizes the leakage caused by the seal is a priority.

Aim: The present study aimed to investigate the effect of meteorological parameters on particulate matter concentration (PM_2.5) in ambient air of Karaj metropolitan. Materials and Methods: In this cross-sectional descriptive study, 17 sampling points in Karaj city were chosen using GIS software. Sampling of PM_2.5 was carried out for 24 h using the sampling pilot during the four seasons in the air of Karaj city. Sampling of PM_2.5 was performed using PTFE filters, peripheral pump, and personal modular impactor. The concentration of particles collected on the filter was calculated by gravimetric method. Meteorological parameters including temperature, humidity, pressure, cloud coverage rate, ultraviolet (UV), and dew point were recorded during sampling through portable devices. Finally, the relationship between PM_2.5 concentration and meteorological parameters was assessed by SPSS24 and Excel software. Results: Seasonal variation trends of PM_2.5 particles showed that maximum and minimum annual concentrations have happened in autumn and spring seasons with a value of 67.48 and 19.85 μg/m³, respectively. Furthermore, the citizens of Karaj are exposed to PM_2.5 pollutants four times more than the Environmental Protection Agency-recommended standard (10 μg/m³). The findings of this study also show that there is a positive correlation between PM_2.5 particle concentration and temperature, relative humidity, and pressure (P < 0.05). Moreover, a weak and negative correlation was found between UV radiation, cloud cover, and dew point with PM_2.5 particle concentration (P > 0.05). Conclusion: The highest concentrations of particles were observed in autumn season. Furthermore, the particle concentration scatter map shows that the central and eastern regions and north of Karaj are more polluted than other areas. Therefore, to protect the health of citizens of Karaj, appropriate policies and strategies should be adopted to reduce the concentration of particulate matter and other pollutants in the ambient air of this city.

Aims: Deep frying of foods at high temperatures results in an increase in the unique sensorial properties of fried food including fried flavor, golden brown color, and crispy texture, which ultimately leads to changes in the physical and chemical properties of the oil. This study was conducted to evaluate the quality of oils used in 60 centers of fast food distribution in Mashhad city. Materials and Methods: A validated questionnaire based on the instruction from the Ministry of Health and Medical Sciences was used to collect the data and to investigate the health status of the places and foods. Total polar material (TPM), temperature, and acidity of the oil were measured using oil test portable device (DOM-24 model) while the peroxide value (PV) was measured by iodometry method. The data were analyzed by SPSS software V.16 via statistical tests including t-test, ANOVA, and Chi-squared tests.Results: The mean values of TPM, acidity and PV in the studied oils were 31.8 ± 7.2 %, 3.7 ± 0.8, 4.7 ± 6.7 meq/kg, respectively. There was a significant relationship between TPM value with acidity, temperature and duration of oil use based on Pearson correlation test (P > 0.005). Furthermore, there was a significant relationship between the PV and area, the type of oil, and sanitation of instruments. Conclusion: The levels of hydrogen peroxide, polarity, and acidity of oils in fast food shops were higher than the guideline values. We recommend that health inspectors systematically monitor the oils fried in these centers.

Aims: Attention to physical, health, and safety factors in educational environments is the most effective and fundamental factor for physical and mental growth of the students and their learning. Hence, one of the most important and influential school health issues is environmental health and safety. Accordingly, this study was conducted to study the environmental health and safety of Evaz district schools. Materials and Methods: This descriptive cross-sectional study was carried out in 2017 and the conditions of environmental health and safety of 16 schools (elementary, secondary, and high schools) were studied in Evaz County. For this purpose, a checklist with 48 questions was prepared. The checklist was prepared based on the Iranian environmental health of schools standards codes and completed by means of observing and interviewing the authorities and the obtained data were analyzed using the SPSS version 16. Results: The conditions of the schools were in an unfavorable status in terms of the healthy storeroom, controlling the insects and rodents, installation electrical safety (insulating) mat under the electrical panels, and installation of handwashing guide. The results showed that there were no pool and fountain, laboratory and workshop, and balcony and terrace in some of those schools. The statistical analysis depicts the significant correlation between the school area and the places for fuel storage and teachers' rest (P = 0.03). Conclusion: Based on the results the schools of Evaz city were in a favorable status in terms of equipment safety and the building sanitary rules, while the status of individual health and building safety was lower than the standard level. So, such items should be considered for health promotion of such schools.

Aims: This study was carried out to understand the awareness, attitude, and practices about needle prick injuries and postexposure prophylaxis (PEP) against human immunodeficiency virus, hepatitis B (surface antigen), and hepatitis C virus among health-care workers (HCWs) of the tertiary care center. Materials and Methods: This was a descriptive hospital-based, cross-sectional study carried out over a period of 1½ year. After informed consent and ethical clearance from the institutional ethics committee, patients were interviewed; previous records about needle prick injuries and PEP were analyzed. HCWs from Queen Mary's Hospital and Trauma Center of King Georges Medical University, Lucknow, India, were evaluated for needle prick injuries and PEP. During the study period, 140 hospital staffs including 74 resident doctors, 40 nurses, and 26 fourth-class employees were interviewed. Data were obtained from predetermined questionnaire regarding knowledge, attitude, and practices about needle prick injury types, precautions, reporting to the nodal officer, and delay in PEP if accidentally needle pricked. Results: Out of 140 participants, 105 (75%) were aware about PEP and 93 (66.42%) HCWs had positive attitude toward PEP. A total of 34 (24.28%) patients were injured, including 10 doctors, 16 nurses, and 8 fourth-class employees. 100% doctors, 50% nurses, and 42.3% fourth-class employees had knowledge about PEP. Out of 13 deep penetrating needlestick injuries, 4 injuries occurred during injection administration, 4 of them during suturing, and 5 during recapping. After exposure, all 13 cases had received PEP and all were seronegative after 6 months of follow-up. Conclusion: Needlestick injuries and sharp object injuries represent a major health problem to HCWs. Prevention should be based on immunization, education of HCWs, and proper training about biomedical waste management.

Aims: Organophosphates are well-known as an important group of poisons. The aim of the current study is to investigate acetylcholinesterase enzyme (ACHE) level in workers' blood of a poison-producing industry and its relationship with annual poison production and the use of personal protective equipment (PPE). Materials and Methods: This cross-sectional study was conducted during 2012–2015 on 84 workers from different units of a poisons-producing industry and a 20-person control group. The PPE used during the years of study includes Asphalt gloves, rubber gloves, and mask felt. The AChE level was detected based on the modified Ellman method. Results: The maximum AChE level was observed in the control group. In addition, the minimum was found in the workers in 2015. The mean AChE level in the control group was significantly higher than that in the worker (P < 0.05). The mean AChE level in the workers based on the study years was significantly different, but this was not significant between the blood samples taken in the years of 2014 and 2015. Furthermore, it was found that both poisons-producing amount and PPE distribution were enhanced more during the past year of the study, while the poison amount entering to the body decreased. Conclusion: It was deduced that the AChE level in workers' blood was lowered with increasing at the exposure years due to irreversible effects. It is also observed that growth at the PPE application acted as an important parameter to decline exposure to poisons and subsequently various health complications.

Aims: Nitrates in drinking water which may come from nitrogen fertilizers applied to crops are a potential health risk. The present study was conducted to investigate the application of alternating current (AC) in electrocoagulation (EC) process for nitrate removal from aqueous solution and linear and nonlinear isotherm modeling.Materials and Methods: The experiments were performed in pilot scale. The effective parameters including solution pH, the initial concentration of nitrate, total dissolved solids, contact time, and current density were studied. Results: The obtained results showed that with increasing solution pH from 3 to 10, the sinusoidal removal efficiency was observed. With increasing current density from 0.5 to 2 A/cm², the nitrate removal efficiency was ascended from 32% to 58%. The optimum electrolyte was 2 g/L of NaCl. With increasing contact time and decreasing initial nitrate concentration, the nitrate removal efficiency was enhanced. In addition, the adsorption NO₃by AC EC was preferably fitted with Langmuir isotherm. Conclusion: The results showed that the EC process could remove the nitrate to less than Iranian standard limit. The solution pH, current density, and contact time were showed the direct effect and initial concentration of nitrate depicted the reverse effect on nitrate removal efficiency.

Aim: Application of composting process for the management of organic solid waste led to the production of leachate, which causes many problems to environment. This study was aimed at investigation of ferro-sonication (FS) process in composting leachate degradation. Materials and Methods: Leachate samples were collected in composting factory located in Isfahan. In each run, 400 ml of leachate was sonicationed through an ultrasonic homogenizer in a cylindrical glass reactor. Ferrous sulfate was added to the reactor as accelerator agent. The effect of various parameters including pH, ferrous sulfate doses, sonication times, and ultrasonic intensity was studied in the removal of chemical oxygen demand (COD) and biological oxygen demand (BOD) from composting leachate. Results: The results showed that the COD and BOD removal rate was increased by increasing ferrous sulfate dosages, sonication time, and ultrasonic intensity. In addition, lower pH was favored for leachate degradation. In general, the optimum conditions for pH, ferrous sulfate dosage, irradiation time, and ultrasonic intensity were 3, 8 mmol, 180 min, and 150 W, respectively. Approximately 46% of COD and 33% of BOD were removed in optimum condition. Conclusion: These results revealed that FS can be effective in degradation of compost leachate and can be presented as a good choice for pretreatment of leachate.

Aims: The ability of extracellular polymeric substances (EPS) production was observed in many species of heterotrophic microorganisms through the biological wastewater treatment systems. Materials and Methods: The batch experiments at different carbon/nitrogen and solid retention time (SRT) were carried out to investigate the effects of initial nitrogen concentration and SRT on EPS production and chemical oxygen demand (COD) removal efficiency. The artificial neural network (ANN) was developed to modeling of obtained data. Results: The results showed that: (i) with increasing SRT, the COD removal improves; (ii) initially, the amount of carbohydrate increases as SRT increases; however, with further increase of SRT, it declines; (iii) the protein/carbohydrate ratio improves as SRT decreases; (iv) the carbohydrate and protein concentration of soluble EPS increased with increasing initial nitrogen concentration from 0 to 10 mg/L; and (v) further increase of initial nitrogen concentration lead to depletion of carbohydrate production. Conclusion: The highest yield (Y) value was calculated at low sludge age and deficient initial nitrogen concentration, which may be due to the application of EPS production mechanism. The ANN model moderately predicted effluent COD concentration, carbohydrate, and protein production.

Aims: Phthalates (e.g., diethylhexyl phthalate) act as one of the endocrine disruptive compounds and can have adverse effects on different biological pathways including hormonal receptors, affecting the synthesis, secretion, or metabolism of hormones. The aim of this study was, method development of the dispersive liquid-liquid microextraction (DLLME), to determine the monoesters of diethylhexyl phthalate in children and adolescents in Isfahan city, Iran. Materials and Methods: This study was conducted in 2016 (during a year) on 242 children and adolescents, aged 6–18 years, living in Isfahan, Iran. In this method, acetonitrile and chlorobenzene were used as disperser and extractant, respectively, to extract the investigated monoesters. The analytes were determined by gas chromatography–mass spectrometry. Results: Acetonitrile (as disperser) and chlorobenzene (as extractant) were used for monoester phthalates extraction (750 μl of acetonitrile and 80 μl of chlorobenzene). The results indicated that the recovery and relative standard deviation (RSD) of the utilized method were 55–109 and 6.3%–13.2%, respectively. The limit of detection and limit of quantification (LOQ) of the method were 0.024–0.088 and 0.05–0.48 μg/L, respectively. Monoethylhexyl phthalate (MEHP), monoethyl oxo-hexyl-phthalate (MEOHP), and monoethyl hydroxyl-hexyl-phthalate (MEHHP) were observed in 99.6%, 95.87%, and 96.28% of the studied samples, respectively. The mean concentration of MEHP, MEOHP, and MEHHP in the study population was 151.7 ± 143.8, 258.26 ± 143.07, and 194.17 ± 147.3 μg/L, respectively. Conclusion: Acetonitrile (as disperser) and chlorobenzene (as extractant) were suitable solvents for phthalate monoesters extraction in method development of DLLME. On the other hand, the mean concentrations were very high values in comparison with other similar studies that require the attention and legislation regarding limitation of the application of phthalate compounds.

Aims: Health-care waste is one of the most crucial issues in solid waste management due to its adverse effects on human health and the environment. The aim of this study was to investigate the present situation of health-care waste management in Sajadieh Hospital in Torbat-e Jam to find the major challenges and offer the best practice regarding this issue. Materials and Methods: This cross-sectional study was conducted in Sajadieh hospital in Torbat-e Jam in 2017. The total amount of waste produced in hospital was measured for 3 months. Waste management pattern was carried out based on a checklist obtained from the Ministry of Health (MOH) of Iran. Excel software was employed for data analysis. Results: In total, the mean amount of wastes generated in studied hospital was 658.9 kg/day, including domestic waste (397.6 kg/day) and hazardous waste (261.4 kg/day). The highest amount of hazardous wastes was generated in operating room with 32.9 kg/day. Quantity analysis of total waste showed that food wastes (25%) comprise the highest fraction. Based on MOH checklist, the status of the waste management practices was determined as fair. Conclusions: The results of this study showed that despite the segregation of hospital wastes, the amount of hazardous wastes were higher than recommended guidelines. Therefore, more attention of the authorities and the correction of hospital waste management are required.

Glyphosate is the most widely used agricultural herbicide in the world and in the United States. In this study, we measured glyphosate levels in water, foods, and human urine samples. We also specifically examined possible correlations between urinary glyphosate levels and physiological, dietary, or behavioral factors. The results show that water samples obtained from both Lake Erie and tap water contained nondetectable or very low levels of glyphosate (≤0.08 ppb). On the other hand, food samples showed various levels of glyphosate contamination. In particular, tea products (40–728 ppb in five samples), coffee powder (11 and 26 ppb in two samples), and honey (20 ppb) had higher glyphosate concentrations in comparison to other foods. Glyphosate was also detected in human urine samples, in particular at elevated levels (~2 fold) from participants who consumed tea in the past 24 h.

Aims: Fatigue can be defined in various conditions. In literature it has been defined and explored by various researches through different aspects. This study was conducted to establish the relationship between the duration of work exposure and feeling of subjective fatigue. Materials and Methods: Twenty-one jewelry manufacturing workers as study group and 27 students as control group participated with their signed informed consent. The daily diary method and feeling of subjective fatigue evaluation questionnaire were used as a tool in this study. Three categories of feeling of subjective fatigue were considered in this study. The study was conducted mainly in the middle of the week. The data regarding feeling of subjective fatigue were collected before starting of work and after completion of the work day. Results: The results showed that The time spent on the job by the workers engaged in jewelry manufacturing was 670 min and were in four slots with the longest work period being 240 min. Sleeping time was found to be around 480 min. Conclusion: The study revealed that all three dimensions (general, mental, and physical) were affected by the whole day work exposure. Among three types of fatigues, general fatigue was observed at the beginning and end of the work shift.

Aim: In this study, the decolorization of methylene blue (MB) by the electro-Fenton process using stainless steel (SS) mesh electrodes was examined. Materials and Methods: The effects of initial dye concentration, pH, and ratio of Fe: H₂O₂, current density, and type of electrode were studied. The kinetics of the reactions was also studied. Results: The highest removal rate 99%was obtained at pH 3 within 20 min. Kinetics experiment studies showed that removal of dye was faster at lower initial dye concentrations. The results revealed that color removal was highest at a Fe²⁺:H₂O₂ ratio of 1:4. An increase in current density resulted in an increase in oxidation rate and faster removal of color. The results demonstrated that increasing the size of the mesh pores led to an increase in the percentage of dye removal. The highest removal percentage (94.5%) was observed in 25 min with a mesh 2 electrode. The constant rate of dye removal on steel mesh 2 was 6.6 times higher than a steel plate. Energy consumed in this state was = 1.6 kWh/m³, compared to 2.6 kWh/m³ under other conditions. Conclusion: Using SS mesh electrodes was very effective in color removal for MB under optimal conditions. The present study showed that increasing the steel mesh size improved the conditions for color removal and reduced the energy consumption. Therefore, it is suggested that steel mesh be used as an electrode for electrochemical processes.

Aim: The aim of this study was to investigate the degradation of an azo dye, reactive red 198 (RR198), by ozone, H₂O₂/O₃, and persulfate from aqueous solutions. Materials and Methods: The application of several advanced oxidation processes including single ozonation, O₃/H₂O₂, and persulfate for degradation of RR198 at concentration of 200 mg/L was investigated. The effect of various parameters including pH, H2O2, persulfate doses, and temperature was studied on the degradation of RR198 from aqueous solutions. In addition, the effects of these processes on biodegradability of RR198 were evaluated. Results: The results showed that the degradation rate was increased by increasing H₂O₂ concentration. The optimum H₂O₂ concentration was obtained in the range of 0.03 mol/L at dye concentration of 200 mg/L. Alkaline pH, higher temperature, and persulfate dose (12 mM) were favored in dye and COD removal. Moreover, compared with ozone and peroxone, the persulfate oxidation could achieve a higher color and COD removal at the same reaction time. Persulfate has greater potential to improve the biodegradability of RR198 solution than ozone and ozone/H₂O₂ process. Biochemical oxygen demand/COD ratio of the dye solution treated by persulfate, ozone/H₂O₂, and ozone at reaction time 40 min was 0.73, 0.63, and 0.59, respectively. Conclusion: These findings show that oxidation by persulfate is a promising alternative for the treatment of RR198 containing solution as a recalcitrant pollutant.

Aims: The purpose of this study was to investigate adsorption isotherms of removing bisphenol A (BPA) from aqueous solutions using magnetic nanoparticles Fe₃O₄ and SiO₂. BPA is an endocrine disrupting chemical that has caused great concern because of its potential risk to human health. Materials and Methods: The combined of magnetic nanoparticles Fe₃O₄ and SiO₂ were applied to remove BPA from aqueous solution at a dose of 2 g/L. Isotherm Fitting Tool software was used for isotherm study in contact time 20 min, the initial concentration of BPA 0–10 (interval 1 mg/L), and pH 5. Results: The maximum adsorption efficiency was found to be 55%. The results of our experiments showed that maximum adsorption efficiency was achieved at t = 20 min and pH 5. Conclusion: The isotherm study showed that Langmuir isotherm described the equilibrium adsorption data better than other isotherms alternative.

Aims: In this work, activated carbon, magnesium oxide (MgO), and MgO stabilized on activated carbon derived from sweet corn were applied as catalysts for oxalic acid degradation from aqueous. Materials and Methods: Sweet corn pile was used for the production of activated carbon, and magnesium nitrate applied for the production of MgO. Ozone concentration determined using iodometry method, and oxalic acid concentration was determined by a spectrophotometer at 210 nm. Moreover, the effect of MgO, activated carbon and oxalic acid concentration, pH, contact time, and oxalic acid mineralization were investigated. Results: The results showed that ozonation in the presence of activated carbon or MgO and/or MgO stabilized on activated carbon, increased the decomposition rate of oxalic acid. Removal efficiency of oxalic acid with increasing catalysts dose of 0.05–1 g, pH of 3–11, and time of 1–30 min have increased from 72% to 85%, 72% to 85%, and 92% to 95% respectively. Furthermore with increasing of oxalic acid from 40 to 100 mg/L, the removal efficiency decreased from 96% to 88%. Conclusion: According to this study, catalytic ozonation processes have shorter time and more removal efficiently than the single ozonation process. Moreover, the results showed that oxalic acid was mineralized significantly and interfering factors have negligible effect on the catalytic ozonation process than the single ozonation.

Aims: Present study was done by using upflow anaerobic sludge blanket (UASB) reactor to investigate the effect of influent chemical oxygen demand (COD) and organic load rate on the formation of anaerobic granules in wastewater treatment. Martials and Methods: Upflow anaerobic sludge blanket reactor with working volume 30 L was studied using actual slaughterhouse wastewater at a hydraulic retention time of 1.24 d and at temperatures in the range of 35°C ± 0.5°C for 320 days. The inoculum was extracted from the anaerobic digester of municipal sewage treatment plant, and the UASB reactor was filled with 8 L of sludge. Results: The results indicated that under the optimal conditions, about 94.6% of COD could be effectively removed from slaughterhouse wastewater with the UASB. The highest and lowest COD removal efficiency was 40.5 and 94.6% corresponding to influent COD of 1266.8 and 1222.2 mg/L, respectively. The fluctuation of solution pH in UASB operation was in the range of 6.68-8.03. The average of solution pH was 7.46 ± 0.36. The solution pH was gradually improved with UASB operation. Different granule sizes coexisted in the UASB reactor, but granules with the size of 1-3 mm were predominant. The maximum observed size of anaerobic granule was 7 mm. Conclusion: Application of slaughterhouse wastewater as feed wastewater demonstrated that the slaughterhouse wastewater to be more effective in promoting the formation of anaerobic granules and granule size in UASB reactor.

Aims: The quantity, composition and physiochemical characteristics of wastes are important factors in selecting an appropriate treatment method. Having knowledge about the current status of medical wastes in any region is necessary for the establishment of effective medical waste management. Martials and Methods: In this field study, official data obtained from the national statistical center were used. The statistical population for sampling and physical analysis includes two hospitals and five health-care centers, selected randomly, and WHO standard procedures were followed for wastes segregation. Results: Based on data obtained, 1335 kg of medical wastes is daily generated in Gachsaran County of which 563 kg are infected and 772 kg are noninfected. A minor part of medical wastes are incinerated or delivered to the municipality untreated. However, the major part is hydroclaved. The largest medical center in the region is Shahid Rajaei Hospital located in Dogonbadan city and infected wastes from the whole region are sent to this center to be hydroclaved. Conclusion: In conclusion, the quantity of infected wastes in the region is higher when compared to other cities in Iran. The high quantity of infected wastes may be a result of poor separation of infected and noninfected wastes by personnel due to lack of required knowledge.

Aims: In the present study, a risk assessment for growth of Clostridium botulinum in model seafood deli salads was performed along with the effect of growth of resident microbes on the intrinsic and extrinsic properties of the product. Furthermore, high hydrostatic pressure (HHP) was applied to induce the germination of the surrogate spores. Materials and Methods: Five batches of seafood deli salads were stored at 4°C for up to 42 days, with samples being withdrawn periodically for microbial and chemical analysis. The extrinsic (oxygen content of the headspace) and intrinsic (redox potential, pH, and water activity) properties were determined along with microbial counts (total viable counts [TVCs], yeast and mold, lactic acid bacteria) over the product shelf-life. The data generated were then uploaded into a predictive model, and the potential growth of C. botulinum was assessed under different storage conditions. Furthermore, product inoculated with Bacillus atrophaeus was pressure treated at 400, 500, and 600 MPa for 1, 2, and 3 min at 20°C. Results: From analysis of the deli salads during storage at 4°C, the TVC remained below 2 log colony forming unit (CFU)/g with no lactic acid bacteria being detected. The yeast and mold count progressively increased during the storage period attaining 6 log CFU/g at the end of the 45-day storage period. There was no change in the pH and oxidation-reduction potential of the deli salads during storage. Predictive model indicated that in storage at 4°C and pH 5.1 and a water activity of 0.974, the generation time was 561.37 h. Only one log spore germination induction was observed when HHP treatment was performed at 600 MPa for 3 min. Conclusions: From predictive modeling, it was determined that based on the intrinsic and extrinsic factors of stored deli salad, the growth of C. botulinum was unlikely. In addition, the application of HHP did not significantly induce germination of the surrogate spores.

Aims: In this research, application of fishery wastes as locally available, cheap, eco-friendly, non-toxicity, reusable, abundant biodegradable resources and highly efficient adsorbent was studied for Direct Blue-86 (DB-86) removal from aqueous solution. Materials and Methods: Comparison of the adsorption of DB-86 by chitosan produced from three different fishery wastes (shrimp, crab and squid collected from Persian Gulf) has been investigated. Effects of adsorbent dosage, pH, flow rate, ionic strength, interfering ions and dyes were evaluated. Results: The results indicated that maximum removal of dye (~ 100%) was obtained by passing 100 mL of DB-86 (50 mg L-1, pH=2) through a column containing 0.5 g chitosan by using continuous method (fixed-bed) at room temperature (25 ± 2 °C). Maximum desorption of 72% was achieved at alkaline medium (pH=13.5). It was shown that equilibrium isotherm could be fitted by the Langmuir equation. The maximum adsorption of chitosan (qm) and the energy of adsorption were calculated as nearly 60 mg/g and 3.6 mg-1, respectively. Conclusion: Chitosan was successfully used for removal of DB-86 from spiked Karoon River sample and the effluent of Pars Paper Factory, a local pulp and paper factory in Ahvaz. Results represent of three replicated experiments.

Aims: This research was done to assess the dechlorination and destruction of polychlorinated biphenyls (PCBs) in real-waste transformer oil via microwave (MW) radiation. Materials and Methods: The influence of MW power, reaction time, polyethylene glycol, zero-valent iron powder, sodium hydroxide (NaOH), and water (H ₂ O) were investigated on the dechlorination and destruction efficiency of PCBs in real-waste transformer oil under MW radiation. Results: The findings show that polyethylene glycol and NaOH have great influence on destruction of PCBs. However, iron (Fe) did not have any influence, and H ₂ O decreased the destruction efficiency of PCBs. Moreover, experimental data showed that with optimum amount of variables [ie, polyethylene glycol (PEG) = 5.4 g, NaOH = 1.13g, Fe = 0.6g, H ₂ O = 0.8 mL, and MW power of 800 W], more than 99.9% of PCBs were destructed at reaction time of 6 min. Furthermore, destruction of PCBs in the absence of water increased up to 100% after 6 min. Conclusion: Accordingly, results showed that MW radiation and reactants (PEG and NaOH) were very important factors for the destruction of PCBs from real-waste transformer oil.

Aims: In this study, the removal of nitrate was investigated using nanocrystalline cellulose (NCC) extracted from sugarcane bagasse. Materials and Methods: NCC was extracted by acid hydrolysis of bagasse at 40°C for 45 min and then used as an absorbent for the removal of nitrate. The properties of absorbent were evaluated by atomic force microscopy and dynamic light scattering. The effect of various parameters including pH, initial concentration of nitrate, adsorbent dose, and exposure time was investigated on the removal of nitrate. Results: NCC was obtained in a diameter and length of <14.7 and 500 nm, respectively. Optimal conditions for removal of nitrate were determined in the initial nitrate concentration, adsorbent dose, pH, and exposure time of 100 mg/L, 6, 3 g/L, and 100 min, respectively. In optimal conditions, the maximum adsorption of nitrate was 8.33 mg/g. Conclusion: The highest efficiency of nitrate removal at pH, 6 was obtained as 25%. The results showed that the NCC, extracted from bagasse, could be used as a very effective adsorbent to remove nitrate from water and wastewater resources.

Aims: The purpose of this study is to investigate the zinc (Zn) and nickel (Ni) removal from aqueous solution by coagulation-flocculation using polyaluminum chloride (PACl) and chitosan (CS) biopolymer. Materials and Methods: This study was a laboratory scale experiment, which used PACl and CS to remove Zn and Ni with concentrations 3-100 mg/L from aqueous solutions. Jar test was used to compare the Zn and Ni removal efficiencies of the chemical treatment options using PACl and CS. The dosages used for PACl ranged from 5 to 100 mg/L whereas CS dosages varied between 5 and 75 mg/L. Results: The results showed that optimum coagulant doses and pH were found at 50-100 mg/L and 11 for PACl and 20-75 mg/L and 11 for CS, respectively, when CS added with PACl led to a better removal efficiency of the metals (more of 99%). In mixed aqueous solution, the presence of Zn caused increase of Ni removal efficiency and the presence of Ni caused decrease of Zn removal efficacy. Conclusion: The results of this study showed that CS had higher removal efficiency than PACl for removal of Zn and Ni, and also CS as a coagulant aid led to increasing in metal removal.

Aims: The purpose of this study was to evaluate ergonomic assessment MSDs risk in computer users with Rapid Upper Limb Assessment (RULA) method and Nordic questionnaire. Materials and Methods: This cross-sectional study was conducted on 96 computer users in computer sites, Isfahan University of Medical Sciences. The data were analyzed using test SPSS 20 and descriptive statistics and ANOVA test. Data collection tool was Nordic questionnaire and checklist RULA. Results: By Nordic questionnaire, the results showed that MSDs prevalence in computer users were, in the neck (54.9%), back (53.1%), and elbow (43.2%) more than in other parts of the body. Based on the level of risk, RULA was 24 individuals in an area of low risk, 41 individuals area of caution, and 31 individuals in the area hazard. MSDs prevalence was in women more than men. Furthermore, ANOVA test showed that there is direct and significant correlation between age and work experience with a final score RULA (P < 0.001). Conclusion: This study result showed that frequency of musculoskeletal problems in the neck, back, elbow, and wrist was generally high among our subjects, and ergonomic interventions such as computer workstation redesign, users educate about ergonomic principles computer with work, reduced working hours in computers with work must be carried out.

Aims: The present study was carried out to evaluate the production of eco-friendly and environmentally bio-fertilizer from a mixture of food waste (FW) and rice bran (RB). Materials and Methods: The various mixtures of RB and FW (1:1, 1:2, 1:3, and 1:5) were prepared and spread in Diy beds for 20 days. After that, the raw compost was poured in four containers beds contains 100 adult earthworms Eisenia foetida for 30 days. Physical and chemical parameters including temperature, humidity, carbon to nitrogen (C/N) ratio, and pH were monitored. Results: The obtained results showed that at the first of composting process, the temperature was sharply increased and after that dropped and reached to the ambient temperature. The C/N ratio was decreased in studied Diy beds during preparing and vermicompost processes. The averages of C/N ratios in the raw FW and RB at mixing ratios of 1:1, 1:2, 1:3, and 1:5 were 45.35, 38.43, 35.3, and 32.11, respectively. The C/N ratios in the vermicompost were reduced to 20.85, 18.3, 16.86, and 15.16, respectively. Conclusion: The results of this study showed that composting and vermicomposting process can be used as a potential tool for bio convert rice bran and food waste. However, it is suggested that the rice bran can be amended with food waste to ensure better quality of vermicompost.

Aims: The aim of this study was to evaluate a membrane bioreactor (MBR) system for optimization effluent quality by feeding of the influent (raw wastewater and anaerobic reactor effluent) in Isfahan - Mourchekurt Industrial Estate Centralized Wastewater Treatment Plant. Materials and Methods: The MBR was equipped with two flat sheets membrane with 0.2 μm pore size, were operated in parallel style and feed simultaneously with raw industrial wastewater (MBR1) and anaerobic reactor effluent (MBR2). The average organic loading rates in two reactors were 1.37 and 0.52 (kg chemical oxygen demand [COD]/m ³ .day), respectively. All analyses were implemented according to the standard methods procedure. Results: The average concentration of COD was lower than 100 mg/L and 50 mg/L in both reactor effluent, respectively, and it was <30 mg/L for biological oxygen demand (BOD ₅ ) in both reactors. In addition, the average turbidity, COD, BOD ₅ and total suspended solid removal were higher than 92%. In both reactors effluent, average microbial indicators contamination were >1000 MPN/100 mL for MBR1 and these were <1000 MPN/100 mL for MBR2. During the operation flux reduction in MBR1 was more than MBR2. Conclusion: The MBR technology was used to treat the combined industrial wastewater was efficient, and its effluent can be perfectly used for water reuse. The MBR performance was improved by applying an anaerobic pretreatment unit.

Aims: The sonoelectrochemical mineralization of the synthetic aqueous solution of the perfluorooctanoic acid (PFOA) on Ti/PbO ₂ anode was investigated using the response surface methodology based on a central composite design (CCD). Materials and Methods: The CCD was performed using three different variables such as current density (CD) (mA/cm ² ), pH, and supporting electrolyte (EL) concentration (mM). The total organic carbon (TOC) removal was determined as an indicator of PFOA mineralization. A Shimadzu TOC analyzer was used to measure the TOC of the samples. The Ti/PbO ₂ electrode was prepared using the electrochemical deposition method. In order to enhance the electrochemical mineralization, ultrasonic (US) radiation was used. The US frequency was 20 kHz. Results: The optimum conditions for PFOA mineralization in synthetic solution were EL concentration of 94 mM, pH of 2, and CD of 83.64 mA/cm ² , which resulted in complete TOC removal. The results indicated that the most effective factor for PFOA mineralization was CD. Besides, the TOC removal efficiency significantly increased with increasing CD. Conclusions: Under optimum conditions, the mineralization of PFOA was almost completed after 90 min of sonoelectrolysis. Therefore, sonoelectrolysis was found to be a more effective technique for mineralization of an environmentally persistent compound.

Aims: The purpose of the present work was to consider the effect of different samples thicknesses on the acoustic absorption coefficient. Materials and Methods: An impedance tube was built with two microphones accordance to ISO-10534 and the American Society for Testing Materials-E1050 standards. For the measurement of absorption, the study was carried for 25 and 30 mm thicknesses of closed cell polyurethane foam, polystyrene, polyvinyl chloride (PVC), rubber, mineral wool, carpet, and glass samples. Measurements were performed by impedance tube and VA-lab4 software. Results: In carpet and mineral wool with more thickness, the absorption was increased but, the carpet with less thickness showed more sound absorption in the frequency range of 1500-3600 Hz. The peak of the absorption coefficient of 25 mm glass was 0.36 that the amount was reduced to 0.2 in the 30 mm thickness. Furthermore, the difference between the peak absorption of two thicknesses in polystyrene sample was equal to 0.29. In fact, polystyrene with less thickness had better sound absorption. The same situation was happened for glass in frequencies of below 4500 Hz with less thickness. Conclusion: Incident sound energy, which is not absorbed, must be reflected, transmitted, or dissipated. The porous materials had a higher absorption coefficient. Carpet and mineral wool samples had the highest absorption coefficient, but the materials such as polyurethane foam, PVC, and rubber had lower sound absorption.

Aims: In present study, the mass transfer-reaction kinetic parameters of nitric oxide (NO) removal by ultraviolet (UV)/H ₂ O ₂ process in a bubble column reactor in the presence of SO ₂ are calculated. Materials and Methods: The mass balance equation for NO through a layer thickness of δ, under the steady state condition is solved, and NO absorption rate is calculated. The value of rate constants and Ha numbers are obtained based on experimental data under different conditions. Results: The calculations indicate that the values of Ha number are >3. The values of rate constants (k _obs) are fitted to some empirical equations for different operating conditions. It is observed that the value of k _obs increases with an increase in H ₂ O ₂ concentration and UV radiation intensity while it decreases with an increase in NO and SO ₂ inlet concentrations. The values of rate constants are in order of 10⁻⁵ , expect for SO ₂ , which are in order of 10⁻⁷ . The results reveal that there is a good agreement between calculated and experimental values where the maximum absolute error is 16.18% related to UV light intensities between 0 and 0.012 W/m ³ . Conclusion: The obtained values of Ha numbers under different condition confirm that the absorption process of gas in the liquid phase is a fast reaction. The maximum error values resulted from a comparison between the calculated NO absorption rates and the experimental ones are acceptable.

Aims: This research was conducted to measure the concentration of asbestos fibers in the ambient air of high traffic areas of Isfahan and to evaluate their spatio-temporal variation during summer 2015. Materials and Methods: Air samples were collected from eleven points covering traffic areas of the Isfahan city including Enghelab square, Azadi square, Bozorgmehr bridge, Ghods square, Ahmedabad square, Artesh square, Emam Hossein square, Nazar junction, Vafaei junction, Felezzi bridge, and Tayyeb fork during 3 months of summer 2015. Scanning electron microscope (SEM) coupled to an energy dispersive X-ray system was utilized to count and identify the asbestos fibers. Results: Seasonal average concentration of airborne asbestos fibers in the studied region was 10.04 ± 4.90 SEM f/l. The results of this study showed that the highest concentration of asbestos fibers was measured in Azadi square (18.08 ± 3.863 SEM f/l) and that the lowest was found in Nazar junction(3.92 ± 1.749 SEM f/l). There was a significant correlation between the concentration of asbestos fibers and atmospheric temperature and humidity (P < 0.05). The mean concentration in September was higher than August and July (11.08 ± 4.66). Conclusion: Heavy traffic in the dense areas of the city, and topographical and meteorological features of the city have a major contribution in asbestos fiber emission which resulted in its exceeded levels from the WHO guideline (2.2 SEM f/l). Therefore, effective strategies such as traffic management, industrial movement, and products replacement can be effective in reducing airborne asbestoses fibers concentrations.

Aims: Levels of asbestos fibers in ambient air of dense areas of Shiraz, Iran, were monitored in winter 2014. Materials and Methods: Sampling was carried out by directing air flow to a mixed cellulose ester membrane filter mounted on an open-faced filter holder using a low flow sampling pump. Fiber counting on the filters was conducted using both phase contrast microscopy (PCM) method to determine total fibers and scanning electron microscopy (SEM) method to identify nonasbestos from asbestos fibers. Results: The average concentration of asbestos fibers in the ambient air of the study in different areas of Shiraz were 1.18 ± 0.28 PCM f/L and 13.64 ± 2.87 SEM f/L, in which a maximum level was measured in Valiasr square (1.89 ± 0.54 PCM f/L [20.37 ± 5.55 SEM f/L]), and that of in Moallem square was in minimum (1.05 ± 0.47 PCM f/L [12.24 ± 3.04 SEM f/L]). Conclusions: The averages of asbestos fibers in all sampling points were higher than the WHO suggested standards for ambient air (0.05 PCM f/L, 2.2 SEM f/L). This may be attributed to the frequent occurrence of heavy traffic, the existence of relevant industries in and around the city, and the topographic characteristics of the city. Therefore, immediate courses of action such as product substitution, traffic smoothing, and industrial sites relocating should be taken to eliminate asbestos fibers emission.

Aims: In this study, the adsorption capacity of dried anaerobic digested sludge (DADS) and dried activated sludge (DAS) for the removal of 4-chlorophenol (4-CP) from aqueous solutions was evaluated. Materials and Methods: Both anaerobic digested sludge and activated sludge were collected from a south municipal wastewater treatment plant in Isfahan. Batch biosorption experiments were carried out to investigate the effects of solution pH, contact time, biosorbent dosage and initial concentration of 4-CP. The residual concentration of 4-CP was analyzed by colorimetry method. Isotherms and kinetic equations were applied to study kinetic and equilibrium of adsorption. Results: Results indicated that, DAS have higher removal potential in comparison with DADS. The optimum pH was detected to be 3 for DADS and 4 for DAS. By increasing contact time and biosorbent dosage, removal efficiency of 4-CP increased for both biosorbents. Furthermore, a decreasing trend was observed when initial concentrations were increased. The equilibrium time for DAS was 2.5 h and for DADS was 4 h. The maximum adsorption capacity were found 1.67 mg/g for DAS and 0.93 mg/g for DADS. The 4-CP removal equilibrium isotherm was modeled by Freundlich equation. Kinetic studies suggested that pseudo-first-order model for DADS and second order for DAS were the best choices to describe biosorption behavior. Conclusion: According to the present study, DAS, have better efficiency for the removal of 4-CP in comparisons with DADS.

Aims: The aim of this study was the evaluation of adsorption kinetics and equilibrium of reactive blue 19 dyes from textile synthetic wastewater by pomegranate seed powder. Materials and Methods: This study is an experimental research, which was performed in laboratory scale. In this study, the parameters such as adsorbent dose, pH and retention time, initial concentration of dye and agitation rate have been investigated. After washing and boiling of pomegranate seeds for 2 h, they dried, milled and finally pulverized by standard ASTM sieves (40-100 mesh). Maximum adsorption wave length (λ_max ) by spectrophotometer ultra violet/visible (model SP-3000 Plus) 592 nm was determined. The Langmuir, Freundlich and Temkin isotherm models and the pseudo-first-order and pseudo-second-order kinetic models were analyzed. Results: According to results, the removal efficiency with adsorbent dose, retention time and agitation rate has a direct relation. Maximum adsorption occurred in the first 60 min. The removal efficiency with initial concentration of dye and pH of solution has indirect relation. The Freundlich isotherm fits the experimental data better than the other isotherms. It was recognized that the adsorption followed by pseudo-second-order model (R² > 0.99). Conclusion: Based on the results, pomegranate seeds as a new natural sorbent can be used in removal of dye and other environmental pollutants with desirable absorption capacity.

Aims: The objective of this research was an evaluation of hand-held tools vibration acceleration such as circular saw and drill transmitted to operator's and also to determine the role of glove in vibration reduction of those tools. Materials and Methods: In this study, Bruel and Kjaer Vibration meter with a model of 2231 and its analyzer, 2522, along three types of gloves have been used. Accelerometer transducer installed according to International Standard Organization (ISO) 5349:1-2 standards in the case of the operator handles the hand-held tool. In next step, the transducer was placed inside the glove. Results: The results show the most accelerated vibration in axis Y for circular saw while working on Plexiglas. All of the used gloves show a reduction of vibration transmission from tools to hands. Glove of C grouped had a reduction of vibration less than two other groups. Conclusion: Based on ISO 5349-1, 10% of workers who are working with circular saw and drill without using glove will be affiliated to white finger after about 7-12 years. As a whole, the results showed that the anti-vibration gloves should be tested in real conditions before using them.

Aims: In this study, distilled water and dimethylformamid (DMF), an organic solvent, have been compared in different characteristics to be used as the best solvent during EPD. Materials and Methods: Electrical conductivity (EC) of both solutions was compared by dissolving electrolyte and measuring the EC. Ability of dispersion was determined after sonication in different times. Distilled water, DMF and two mixtures of them were utilized in EPD process and in deposition time of 1-5 min. The electrode weight was measured before and after the EPD and the deposit rate was estimated. Results: Among the used solvents, DMF caused a better yield (0.4 mg/cm ² ) at the optimum deposition time of 4 min. Though it did not have the ability of dissolving electrolyte and could not make an electrical field during EPD; it did not cause the electrode's oxidation. Distilled water and mixtures with water resulted in electrode oxidation with no deposition. Their yield was zero or less which indicated the electrodes oxidation. € According to the results, for having a good and stable dispersion through sonication, making an electrode with a homogeneous deposition via EPD process, preventing of electrode's oxidation, and better temperature control DMF is recommended.

Aims: The present study reports the antibacterial efficiency of starch-stabilized nano scale zero-valent iron (S-NZVI) particles on Escherichia coli. Materials and Methods: NZVI was synthesized using NaBH ₄ and FeSO ₄ .7H ₂ O, and characterized by scanning electron microscopy, as well as X-ray diffraction. The effects of concentration, contact time, dissolved oxygen, and stabilization were tested. E. coli was determined by the pour plate method. Results: The results revealed that the complete inactivation (100%) of E. coli was occurred at using 100 mg/l of NZVI after 30 min under anaerobic condition. The inactivation efficiency was decreased in an aerobic condition. When NZVI concentration increased to 500 and 1000 mg/L, complete inactivation was achieved under both anaerobic and aerobic condition. In general, E. coli inactivation efficiency using NZVI was strongly dependent on the contact time and the concentration of NZVI particles with its maximum efficiency at 500 mg/L within 120 min. Stabilization-NZVI by starch did not improve its bactericidal activity and the inactivation of E. coli by stabilized nanoparticles required higher concentration compared to that by nonstabilized nanoparticles. Conclusion: The present study showed that nonstabilized Fe ⁰ nanoparticles have higher bactericidal efficiency than that of S-NZVI. This investigation also suggests that NZVI can be used as an effective and strong agent for antimicrobial applications.

Aims: In this study, which was done in Persian Gulf Mining and Metal Industries Special Economic Zone, the efficiency of "theory of planned behavior" in training the correct principles of manual material handling was investigated. Materials and Methods: To perform this semi-experimental study, based on the theory of planned behavior and method of manual material handling required questionnaires were prepared. After preliminary studies and determining the reliability and validity of questionnaires, the appropriate study population was selected from the workers, and the questionnaires were filled up through interviews. Results: The results showed that subjective norms (safety factor = 0.51, P < 0.001) are the predictors of behavior intention (performing manual material handling correctly) and behavioral control, as well as behavioral intention, are appropriate predictors for behavior change. Conclusion: This study confirms the efficiency of the theory of planned behavior in modifying the workers' manual material handling behavior. But since all constructs of the theory of planned behavior could not predict the behavioral intention for correct manual material handling, it can be concluded that for changing the behavioral intention, other theories also should be taken into consideration.

Aims: The main aim of this study was to investigate the relationship between the amount of wildlife mortality and traffic rates in Khojir National Park, and with regard to that, finding a suitable location for installing signs according to the standard level sign structure. Materials and Methods: In this study, the current placement of wildlife warning signs was assessed in Khojir National Park, 2010, Tehran, Iran and a method to optimize warning sign placement using kernel density estimations was developed based on existing records for wildlife-vehicle accidents. Kernel density estimation is one of the best methods for finding a suitable location for installing the signs. The most promising of these tools is kernel density estimation, at first with questioner has found nearly point and after that with GPS try to register them in visual page. With kernel density prove to find the best radius, because of installing the sign. Results: Finally in this project, the best radius was found to be 50 m from one accident point, because of supporting the optimum location for installing signs, and finding the four points for installing the signs, and for designing wildlife signs using the symbol of maximum species that was injured in vehicle collision. Conclusion: Finding an area for installing wildlife, the designing of warning signs, and other precautions such as wildlife crossings and overpass creation are useful in decreasing wildlife accidents.

Aims: This study was aimed to determine national sanitation foundation water quality index (NSFWQI), sodium adsorption ratio (SAR) and some other parameters such as electricity conductivity (EC) and sodium percent (%Na) to investigate the quality of the Jajrood and the Damavand rivers, the mix of them and Mamloo dam. Materials and Methods: The tested parameters were pH, dissolved oxygen, biochemical oxygen demand, total solids, nitrate, phosphate, turbidity, temperature, fecal coliform, EC, Na, potassium (K), calcium and magnesium. The used indices were NSFWQI, SAR, %Na and magnesium hazard. Results: average WQI for the Jajrood river (S₁), Damavand river (S₂), mix of S₁ and S₂(S₃) and the Mamloo dam (S₄) were 71.7 (good), 64.5 (medium), 70.6 (medium) and 77.3 (good), respectively. According to USA Laboratory Diagram and Wilcox diagram, all the sampling points were in C₃-S₁(very good to good classes), C₂-S₁(good to permissible classes) categories. Conclusion: According to the results, the water of sampling points is unsuitable for direct human consumption. However, for the S₁, S₂ and S₃ as drinking water, advanced treatment may be needed. For S₄ as a drinking water source, conventional treatment may be necessary. All the sampling points are suitable for irrigation purposes under normal conditions.

Aims: The aim of the study is to assess nitrite residual in highly used processed meat products and investigate risk assessment nitrite in the products in growing age group in Isfahan in 2014. Materials and Methods: The study is descriptive and analytical that 180 highly used processed meat product samples for its nitrite residue has been evaluated by Association of Official Analytical Chemists. In this study, the amount of highly used processed meat product consumption in growing age group has been provided by the questionnaire that has been confirmed by reliability and validity. Results: The amount of nitrite residue in 180 samples that has been evaluated is below the standard of Iran (120 ppm). Amount of nitrite intake from meat products that has been consumed by the growing age group was 0.0058 mg/kg that is 8.28% of daily intake of nitrite. Conclusion: The amount of nitrite intake from highly used processed meat products in growing age group is not in risk range for health human.

Aims: In this study, the amount of the reduction in absorption silencer sound filled with Iranian absorbing materials and influence of thickness and density of adsorbent material in silence was investigated. Materials and Methods: We used galvanized channel 0.6 mm with 30 × 30 cm ² dimension and axial fan. Length of absorptive silencer was 50 cm, and there used the mineral wool absorbent. Absorptive silencer as channel was designed to cross a section of channel and silencers after embedded the absorber be identical together. This study deals with a number of variables that affect performance of absorptive silencer in the channel and their impact on reducing the sound pressure level be examined. Results: In the frequencies 125 and 250 Hz a reduction of sound pressure level was found. While in frequency 500 Hz minimal reduction is achieved. In this study, an increase in the thickness of the absorbent material of absorption silencer, there was a little change in the volume decreasing but with increasing density from 80 to 100 Kg/m ³ better results were seen to reduce noise levels and it caused to increase NR rate. Conclusion: According to data from the present study we can used silencer with 5 cm thick and 100 Kg/m ³ density in the reduction of sound pressure level at frequencies lower than 250 Hz in the ventilation system as an effective device.

Aims: This study was carried to control and monitor the sound using LabVIEW software. Methods: The research was done using LabVIEW software, microphones, and data-acquisition card hardware. Environmental information collected as sound pressure level via microphones and then processed by the data-acquisition card hardware. The information is showed by software as a graph or plot in the next step. Results: This software includes front panel, back panel, and connector panel and with these panels, we can determine information such as various frequency weighting and time weighting. Also, can be specified the sound pressure level, sound amplitude, power spectrum, power spectral density, and other sound characteristics. Conclusion: LabVIEW programming capabilities in the field of sound can be referred to the measurement of sound, frequency analysis, and sound control that actually the software acts like a sound level meter and sound analyzer. According to the mentioned features, we can use this software to analyze and process sound and vibration as a monitoring system.

Aims: The ability of single-walled carbon nanotubes (SWCNT) for copper adsorption from synthetic wastewater was evaluated. Materials and Methods: The batch adsorption studies were performed under various laboratory conditions with initial Copper concentrations of 1, 5, 10, and 50 mg/l, adsorbent dose of 0.1-0.4 mg/L, contact time of 1-60 min and pH of 5-8. The solution was mixed with a mechanical shaker with 150 r.p.m. at 20°C. The suitability of the adsorbent was evaluated using Langmuir, Freundlich isotherm models. Results: The optimum pH for the copper removal was 6-7. The capacity of copper adsorption at equilibrium conditions increased by increasing the concentration of the adsorbate. On increasing the initial concentration of the Cu solution, copper removal reduced. The maximum removal of copper was obtained in dose 0.4 mg/L SWCNTs, 10 mg/L concentration of copper, pH: 7 and 10 min contact time, which were equal to 94%. The Both on Freundlich and Langmuir isotherm models gave the appropriate accordance to the adsorption data (R² > 0.99). The maximum copper adsorption capacity obtained 1.33 mg/g by SWCNTs. Conclusion: The adsorption rate of the copper ions from synthetic wastewater in optimal conditions was quick. In these conditions, the SWCNTs were able to adsorb copper ions from the synthetic wastewater, effectively.

Aims: In this study, the toxicity of three metal plating wastewaters were assessed using sequencing batch reactor (SBR) bacteria. Materials and Methods: For determining the growth inhibition in each metal plating wastewater concentration, the cultured SBR bacteria on nutrient broth media were used and after exposure they cultured on nutrient agar media. Each test was performed in three replicates. Mean of three replicate were analyzed, and no observed effect concentration (NOEC), 50% effective concentration (EC₅₀) was calculated using the probit analysis in SPSS version 16.0 software (SPSS Inc., 233 South Wacker Driv). Results: According to the probit analysis, there is no effect on tested bacteria at the concentrations of 1 mL/L, >50 mL/L and >100 mL/L of metal plating wastewaters in sample 1, 2 and 3, respectively. While almost all bacteria will be dead in the concentration of 1000 mL/L of each metal plating wastewater. Maximum and minimum EC₅₀ were recorded for the metal plating wastewater number 3 (with value of 960 mL/L) and number 1 (with value of 6.5 mL/L). On the other hand, the calculation of NOEC using probit analysis showed that sample 1 is toxic even in minimum concentrations because its NOEC was 1.1 mL/L. Conclusion: Results of this study showed that some metal plating wastewaters in the very low concentrations could induce an adverse effect on the bacterial community structures of WWTPs biological units. Hence, it could be recommended that effluent standards and in-situ treatment rules should be applied according to the kind of process in such industries.

Aims: The aim of this study was to evaluate the effectiveness of E-mail-based intervention on safe crossing behaviors among Isfahan University of Medical Science students, in year 2014 in Iran. Materials and Methods: In over all, 78 boy-students with 22.33 ± 1.65 years were participated in an E-mail-based intervening study. They divided into intervention group (n = 38) and control group (n = 40) by use of random allocation. The instrument of data collection included questionnaire of theory of planned behavior constructs and traffic behaviors. Questionnaires were filled out by both groups at the baseline and 6 months after the educational intervention. The safe crossing educational intervention was conducted within 1-month through E-mail service for the intervention group. The control group received no education. Results: Results showed no significant differences between groups in mean of attitude toward safe crossing, subjective norms (SNs), perceived behavioral control (PBC), intention and safe crossing behaviors at baseline (P > 0.05). MANCOVA test demonstrated that there is a significant difference between groups after the educational intervention with adjusting the effect of age (P = 0.001, F = 31.144, Wilks lambda = 0.313). According to the ANCOVA test, after educational intervention, mean of positive attitude toward safe crossing, PBC, intention and behaviors related to safe crossing were increased in intervention group in comparing control group (P < 0.005). Conclusion: E-mail-based intervention can promote safe crossing behaviors among college students. Conducting further studies with focusing on SNs related to safe crossing is suggested.

Aims: The purpose of the present study was to investigating relationship between perceptual strain index (PeSI) with indices heat strain score (HSSI), wet bulb globe temperature (WGBT) in experimental hot condition. Materials and Methods: This study in five different temperature conditions (21°C, 24°C, 27°C, 30°C, and 35°C) was carried out on 15 male students in the climate chamber and on the treadmill with three levels of the activity. The thermal sensation and perceived exertion was recorded for calculating PeSI, and HSSI questionnaire was completed. Results: Pearson correlation test showed a high correlation (r = 0.84) between the PeSI and HSSI (P = 0.001). Also, Pearson correlation test showed between PeSI with WBGT and air temperature, respectively, a good correlation (r = 0.76) and high correlation (r = 0.81) (P = 0.001). Conclusion: The findings of the study showed that the PeSI can be used for evaluating heat strain in the absence of access to other methods of evaluating heat stress since it has an acceptable correlation with valid indices of heat stress. Also, easy application and quick and cost is much less than other evaluating heat strain indices.

Aims: The aim of this study was to investigate sewage sludge quality of Isfahan wastewater treatment plants (WWTPs) as a fertilizer in agricultural lands. Materials and Methods: The samples were collected seasonally from two WWTPs, including North-Isfahan and Shahin-Shahr in 2012 and 2013, seasonally and biochemical parameters were measured for each site. Results: The studied parameters were meet the Iranian standard level, including pH, nitrogen, phosphorous, potassium, calcium, total solids, organic matter, and moisture content except of magnesium. The carbon-nitrogen ratios was varied 7.41-9.45 and 8.7-9 in Shahin-Shahr and North-Isfahan WWTPs, respectively. The organic nitrogen was composed the highest percentage of the total nitrogen (about 78%) and inorganic nitrogen was in normal ranges. The electrical conductivity was varied 5-8.8 ds/m to 4.6-7.5 ds/m in Shahin-Shahr and North-Isfahan WWTPs, respectively. It may contribute to soil salinity in long term. Maximum nitrogen and phosphorous values were related to winter samples in both WWTPs. In Shahin-Shahr WWTP, minimum and maximum of potassium, calcium, and magnesium were measured in spring while they were the highest in spring in North-Isfahan WWTP. Conclusion: Application of sewage sludge of Isfahan WWTP as a fertilizer could be useful regardless to its microbial contents because it provides essential nutrients for plants growth regardless to its fecal and total coliforms.

Aims: The present study was carried out to determine biokinetic coefficients of a pilot-scale adsorption-bio-oxidation process. Materials and Methods: The pilot plant was simulated North wastewater treatment plant, Isfahan, Iran. The pilot plant was operated 135 days under different mixed liquor suspended solids (MLSS) concentrations in aeration tank. In each phase, MLSS value was kept constant to reach a steady state condition. B-stage has a higher hydraulic retention time and SRT than A-stage. Also, in order to determine influence of biokinetic parameters on the effluent substrate concentration, a sensitivity analysis was performed. Results: The coefficients Y, K _d , K _S , and μ_max of A-stage were 1.34 mg VSS/mg sCOD, 0.17 d⁻¹ , 8.61 mg/L, and 2.78 d⁻¹ , respectively. Also, Y, K _d , K _S , and μ_max of B-stage were 0.74 mg VSS/mg sCOD, 0.12 d⁻¹ , 3.34 mg/L, and 71.94 d⁻¹ , respectively. Sensitivity analysis showed that in the A-stage, all coefficients are directly proportional to the effluent sCOD concentration. In the B-stage, K _d and K _S are directly proportional, but μ_max was inversely proportional to the effluent sCOD concentration. Conclusions: All coefficients were in the range of activated sludge coefficients that are mentioned in the literature, except μ_max and K _S of B-stage. However, K _S value of B-stage was close to the desired range. Sensitivity analysis showed that μ_max and K _S have the most influence on effluent substrate concentration (sCOD).

Aims: This study was conducted to compare the effectiveness of conventional technologies, UV irradiation and ozonation process, and UV/O₃ as advanced oxidation processes to remove phthalate from aqueous solutions. Materials and Methods: The initial concentration of di-2-ethylhexyl phthalate (DEHP) was 5 mg/L. The photolysis, ozonation, and UV/O₃ processes were conducted separately at different contact times (5-30 min). Then, the DEHP residuals in the solutions were analyzed by gas chromatography mass spectrometry. The effect of ozone dosage was also evaluated in the range of 50-400 mg/h on DEHP degradation. Kinetic and the rate constants were determined. Results: The results indicated that using UV and ozonation alone, the maximum DEHP removal efficiency were 43% and 50%, respectively. The UV/O₃ process considerably improved the degradation of DEHP up to 80%. The synergistic effect observed in the combined processes mainly due to the effects of UV in enhancing the ozone decomposition, led to higher degradation for 30 min treatment. A kinetic study showed the degradation in UV/O₃ followed the first-order model. In addition, the maximum DEHP removal rate was 74% with 200 mg/h ozone dosage by ozonation alone process, but it was 93% at same condition by UV/O₃ process. Conclusion: It could be found that the UV/O₃ process is a method for DEHP degradation in aqueous solution and may be recommended as a supplement with other processes for treatment of solutions containing low DEHP concentrations.

Aims: This study was conducted to assess health-effects of exposure particulate matter (PM ₁₀ ) in Ahvaz city (located in South-Western Iran), during 2009. Materials and Methods: The adverse health effects of PM ₁₀ were calculated by relative risk (RR) and baseline incidence related to health end point PM ₁₀ . A specialized model, the air quality health impact assessment tool (AirQ2.2.3), was used to assess the potential impacts of PM ₁₀ exposure on human health in Ahvaz city during 2009. PM ₁₀ data was taken from Ahvaz Department of Environment. These data were in volumetric base. Health effects are being related to the mass of pollutants inhaled and should convert on the gravimetric basis. Conversion between volumetric and gravimetric units (correction of temperature and pressure), coding, processing (averaging), and filtering are implemented for solving such problem. Results: The results revealed that approximately 3% of total numbers of deaths and respiratory mortality happened when the PM ₁₀ concentration was over 50 μg/m ³ . Sum of total number of deaths attributed to PM ₁₀ was 1165 cases in 2009. Based on the results of this study, 13% of all respiratory mortality were attributed to PM ₁₀ concentration over 20 μg/m ³ in Ahvaz city during 2009. High percentage of the observed health endpoints was associated with a high concentration of measured PM ₁₀ . Conclusion: Year comparison of PM ₁₀ concentration with standard was revealed particle matter concentration in summer and winter season were higher than standard. Although total mean of particle matter was higher than the standard concentration. The higher percentage of deaths perhaps could be the result of higher average PM ₁₀ or because of sustained high concentration days in Ahvaz.

Aims: In this study, the characterization of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) were investigated in three different industrial sewage sludges in industrial parks of Isfahan province, Isfahan, Iran. Materials and Methods: Sludge samples were collected from three dry bed wastewater treatment plants (WWTPs) within the province during of four seasons of 2011-2012. Gas chromatography-mass spectrometry and inductively coupled plasma were used to measure PAHs and HMs contents in sludge. Results: The average concentrations of Cd, Cr, Cu, Mo, Ni, Pb, As, Hg, and Se in sewage sludge were 305.67, 514, 1019, 6.46, 102.33, 1181.33, 277.33, 226.83, and 6.35 mg/kg dry weight (d.w.), respectively. The concentrations of HMs in most of the sludge samples were above the regulatory limits for the sludge class 1 and 2 to be used in agriculture in Iran. The levels of ∑₈ PAHs varied from 92.33 μg/ the to 257.87 μg/kg d.w. in the sludge, that lower than the limitation value (6 mg/kg) recommended by the Europe Union and US Environmental Protection Agency for land application. Phenanthrene, pyrene, and fluorene were predominant isomers of PAH in sludge samples. The highest value was found in the Morchekhort WWTP. Conclusion: The concentration and composition of PAHs and HMs in sewage sludge varied and depended mainly on the quantity and type of industrial wastewater accepted by the WWTPs. There is a pyrene in sewage samples that is a carcinogenic. The concentration of HMs in sewage sludge was above of standard levels. Finally, we are not recommended the using of industrial sewage sludge in agriculture because of the high value of HMs was found in samples.

Aims: The aim of this study was decolorization of the synthetic aqueous solution of the acid orange 10 (AO10) dye on Ti/SnO ₂ -Sb anode using the response surface methodology based on central composite design. Materials and Methods: The Ti/SnO ₂ -Sb electrode was prepared using the standard thermal decomposition method and three variables: Current density (CD), pH, and supporting electrolyte concentration were assessed. The dye decoloration was monitored spectrophotometrically by measuring the absorbance of the remaining dye at the maximum absorption wavelength (λ _max ) of 475 nm on a ultraviolet-visible spectrophotometer. To measure AO10 mineralization under optimum conditions, chemical oxygen demand (COD) and total organic carbon (TOC) removal also were evaluated. Results: It was found by the model prediction, minimum dye decolorization was 39% (CD = 6 and pH = 7.5) and maximum dye decolorization was 101% (CD = 65 and pH = 2). Thus, the optimum conditions for AO10 decolorization in synthetic dye solution were electrolyte concentration of 75 mM/L, pH of 2, and CD of 65 mA/cm. Under optimum conditions, decolorization of 100 mg/L dye was complete, and 61.3% and 43.9% COD and TOC removal were recorded after 50 min of electrolysis, respectively. Conclusion: High-efficiency electrochemical degradation of AO10 was achieved over Ti/SnO ₂ -Sb anode as a model electrode. It was concluded that the most effective factor for AO10 decolorization was CD. The electrochemical degradation using Ti/SnO ₂ -Sb electrode is a suitable and an environment-friendly method for the degradation of refractory dyes in aqueous solution.

Aims: Feasibility of the anaerobic migrating blanket reactor (AMBR) was investigated for the treatment of composting leachate. Materials and Methods: The AMBR consisted of a rectangular, plexiglas reactor (inside dimensions: length = 43 cm, height = 23.5 cm, width = 10 cm) with an active volume of 10 L. which divided reactor into four identical compartments (2.5 L). Composting leachate was used as a feed. Start-up of a reactor with diluted feed of approximately 10.43 g/L. Chemical oxygen demand (COD) was accomplished in about 44 weeks using seed sludge from the anaerobic digester of municipal wastewater treatment plant and operated continuously at mesophilic phase. The organic loading rates (OLRs) applied to the system was gradually increased from 1 to 19.65 g COD/L.d. Results: The reactor with hydraulic retention time of 10 day at 35΀C and initial OLR of 1 g COD/L.d showed 82.3% COD removal efficiency. The best performance of the reactor was observed with an OLR of 3.79 g COD/L.d. In influent of reactor, BOD ₅ /COD ratio, TSS, VSS and TDS were ranged from 0.47 to 0.69, 1650 to 16,830, 990 to 12,622 and 2630 to 31,240 mg/L and in effluent of reactor were reached to 0.28 to 0.38, 660 to 7452, 346.5 to 4597 and 1860 to 19,490 mg/L, respectively. Conclusion: The AMBR could be an appealing option for pretreatment of organic load in composting leachate and improving the efficiency of the next biological reactors.

Aims: Modification of multi-walled carbon nanotubes (MWCNTs) via ozone was carried out to enhance removal benzene from aqueous solutions. Materials and Methods: Multi-walled carbon nanotubes purchased from the Iranian Research Institute of the Petroleum Industry was oxidized by ozone generator at %80 intensity for 5 min and in 30% NaOCl. Results: The Fourier transform infrared analysis showed that the peaks corresponded to the hydroxyl and carboxylic acid groups in modified MWCNTs (MMWCNTs) are more intense than that in non-MMWCNTs. The images of scanning electron microscopy indicated that the MMWCNTs have a lower degree of entanglement with increased porosity compared to the nonmodified one. X-ray diffraction test showed that structural crystallization was increased following the modification. After modification, the efficiency of MWCNTs was increased by 20%. The optimum condition for initial benzene concentration, MWCNT dose, contact time, and pH was: 100 mg/L, 2000 mg/L, 20 min, and 5 respectively. Conclusion: Our research suggested that ozone modification can be a simple method in improvement of the MWCNTs efficiency for removal of benzene from aqueous solution.

Aims: This study was conducted to determine the Fenton performance on the fluoride removal efficiency from aqueous solutions. Materials and Methods: The removal efficiency of fluoride from aqueous solutions by the Fenton was carried out by preparation of the water solutions. The studied concentrations of fluoride were in the range of 1.5-3.5 mg/L, pH 2-11, contact times 1-17 min, and the Fenton ratios in the range of 1:1-1:10. The SPADNS method was used for fluoride determinations. Results: The optimum obtained values of the studied parameters to maximum 67% removal of the fluoride from the solutions were, the fluoride concentration 2.5 mg/L, pH = 3, Fenton ratio (H ₂ O ₂ :Fe) = 1:2 and the contact time of 15 min. Conclusion: The proposed material has successfully been applied to the removal of fluoride in different aqueous solutions having a broad concentration range of fluoride. The simplicity of the proposed fluoride removal material, high removal efficiency, a short time and the use of safe chemicals demonstrate the high potential of the proposed method for routine fluoride removal from water samples. The obtained results showed that Fenton process in the removal of fluoride concentration could be an effective method for the removal of fluoride.

Aims: In this study, the potential capability of compost in the simultaneous adsorption of gas-phase n-hexane and benzene, toluene, ethyl benzene, and xylene (BTEX) was studied. Materials and Methods: Batch adsorption technique was used to assess the adsorption properties of compost. The pseudo-first and pseudo-second order kinetics were considered in order to identify the possible mechanism of the adsorption process. Moreover, the suitability of the adsorbent was evaluated using Langmuir, Freundlich and The Dubinin-Radushkevich isotherm models. Results: After 24 h contact time, the adsorption capacity of one g compost was 1.42 mg n-hexane and BTEX for initial concentration of 7.74 mg/l. The adsorption capacities were in order of n-hexane < benzene < toluene < ethylbenzene < xylene. This order is in accordance to the ascending octanol-air partitioning coefficient (K _OA ) order of the compounds (the lowest for n-hexane and the highest for xylene). The kinetics data proved a closer fit to the pseudo-second order model, while the isotherm experimental data were a good correlation to both Freundlich and Langmuir models. Conclusion: The experimental data show that a material with an organic matrix, that is, raw compost, has a higher adsorption capacity for the gaseous compounds with higher K _OA . Overall look to the results of this study indicates that although the raw compost could adsorb gaseous n-hexane and BTEX, its capacity may not be sufficient for the continuous removal of VOCs from the air in the compost-based biofilters, in which biodegradation play a key role.

Amis: The present study was aimed to compare and evaluate the level of microbial (parasitic and bacterial) quality and physicochemical conditions of the water from five different types of indoor swimming pools (three men's and two women's pools). Materials and Method: This research was a cross-sectional study. Totally, 60 water samples were collected from five public swimming pools in Kermanshah, Iran. Microbial (parasitec and bacterial) and physicochemical conditions were examined according to the standard method. Results: Results indicated that the average of physicochemical parameters, except temperature, in all women's swimming pools was more sufficient than the men's swimming pools; but, there was no significant difference between them (P > 0.05). Conclusion: It can be said that, gender cannot be very effective (especially, in terms of physiological characteristics of skin) in varying physicochemical conditions and biological parameters in swimming pools. The main reason for changing these parameters might be attributed to some factors, such as type and extent of relationship between physicochemical and biological parameters, characteristics and source of water, type of filtration system, pools' operation and maintenance, effective disinfection, personal hygiene, etc.

Aims: The aim of this study was to determine the prevalence of parasitic infection via vegetables consumed in Isfahan in 2011. Materials and Methods: In this cross-sectional descriptive study, 120 samples of vegetables were collected from 12 sites in the vegetable supply of Isfahan. Then samples were washed carefully with the detergent, the solution condensed with the Sheeters flotation method and ether Ritchie method in case of detecting parasites with microscope. Statistical analysis was done with Excel and SPSS software. Results: Among the samples, 48.4% were infected with pathogenic and nonpathogenic parasite eggs and larvae, and 51.6% of samples were not infected by parasite. Among the contaminated samples, 48.1% were nonpathogenic, and Giardia with a frequency of 0.4% was the only pathogenic parasite that observed. Conclusion: The study showed that the percentage of parasites in raw vegetables was close to zero. However, the previous study in Isfahan city reported 13% contamination. The reduction in intestinal worm infections is probably the result of development of water and wastewater networks, improvement in public health and public knowledge about parasitic infections and different ways of its prevention.

Aims: The aim of this study was to evaluate noise pollution levels (NPLs) in Isfahan, compare with guideline values and providing a zoning map. Materials and Methods: This study was a descriptive cross-sectional type. Totally, 19 stations were selected from most congested areas throughout the city. In determination of these stations, the Isfahan information maps of the city traffic (obtained from Isfahan traffic and transportation organization) were used. Noise parameters L ₁₀ , L ₅₀ , L ₉₀ , L ₉₅ , L ₉₉ , equivalent sound level (L _eq ), sound exposure level, sound pressure level, L _min , L _max , and L _peak were measured using a CEL-440 sound level meter for 3 months of winter 2010-2011. The NPL and traffic noise index were calculated by a mathematical formula. All measurements were carried out twice a day (morning [a.m.] and afternoon [p.m.]) with the time interval of 0.5 h. To prepare the zoning map of the measured L _eq , ArcGIS software version 9.3 was used. Results: The mean and standard deviation of the measured L _eq values in the a.m. and p.m. were 74.6 ΁ 2.78 and 72.6 ΁ 4.43 dB _(A) , respectively. In comparison, there was a significant difference between the average L _eq values of a.m. and p.m. (P < 0.001) and both were higher than the noise guidelines suggested by Iranian environmental protection organization. The zoning maps show that the maximum L _eq in the a.m. (78.3 dB _(A) ) was related to Ferdowsi bridge station and in the p.m. (79.6 dB _(A) ) was dedicated to Jomhoori square station. Conclusion: It can be concluded that as in the most cases the noise levels of Isfahan exceeded from the guideline values. This city is categorized in the noisy/crowded cities in Iran. Thus, noise pollution of Isfahan can be a serious problem and investigating its reasons is recommended.

Aims: This study was conducted to investigate the indoor and outdoor air quality at Ashayer Hospital in Khorramabad, Lorestan, Iran, from May-August 2013. Materials and Methods: Air samples were collected using the ZEFON pump (ZEFON factory, USA) based on manufacturer instructions. Bacteria were isolated via differential methods. Diagnosis of fungi was performed based on amount of fungal colonies growth, shapes, colors, pigments, and microscopic procedure. The effects of various environmental factors including temperature, humidity and outdoor bioaerosol levels were also investigated. Results: Staphylococcus spp. were the most predominant isolated bacteria from studied wards. Furthermore, other microorganisms including Streptococcus spp. Corynebacterium spp., and Micrococcus spp. were also isolated from the hospital air. Moreover, the most frequent fungus in indoor environments of hospital was Penicillium spp., while Aspergillusspp. and Alternaria spp. were the next frequent ones. In addition, the most frequent fungi in adjacent outdoors were Penicillium spp., Aspergillus spp., and Cladosporium spp., respectively. No significant difference was found between the mean concentrations of bioaerosols in inside and outside of hospital (P > 0.05). Conclusion: This study suggests that the bioaerosols level in the hospitals were relatively high. Thus, hospitals should enhance practice of good sanitation protocols and infection control measures.

Aims: The present study aimed to investigate the relationship between traffic noise and drivers' reaction time (RT) and their error in estimates of movement time. Materials and Methods: In over all, 80 university students with at least 3 years postlicense experience of driving were divided into two groups including traffic noise exposure and control group. S5 test of Vienna test system package was used for assessment of RT. In addition, time-movement anticipation was employed for measuring the rate of error in estimation of movement time before exposing to the traffic noise. After a 1-month interval, participants in the experimental group were exposed to traffic noise about 2 h and the tests were performed again for both groups. Results: Accordingly, RT was statistically higher after traffic noise exposure for male and female. However, there was no significant difference between time of movement before and after exposure to traffic noise both for male and female (P > 0.05). In addition, no difference was shown between movement time, number of accurate estimates, and number of estimates with gross errors before and after of traffic noise exposure in experimental and control group. Conclusion: The results suggest that traffic noise may be associated with poorer mental processing, which can result in longer RT during driving. Therefore, traffic noise would expose drivers to consequent accidents and incidents.

Aims: The purpose of this study was to remove azonium compound using the photocatalytic property of nickel (Ni)-doped titanium dioxide (TiO ₂ ) nanoparticles coated on Iranian natural zeolite. Materials and Methods: Nickel-doped TiO ₂ nanoparticles with the molar ratios of 0, 0.17, 2, 9% Ni/TiO ₂ were prepared via the sol-gel process and coated on Iranian natural zeolite clinoptilolite (CLI). Afterward, X-ray diffraction, scanning electron microscopy and inductively coupled plasma studies were conducted to describe Ni and titanium. Photocatalytic removal of azo dye in concentrations of 25 and 50 mg/L was performed by fixing the composite under ultraviolet irradiation. Results: TiO ₂ nanoparticles in both the anatase and rutile phases were obtained via the sol-gel method with the ratios of 86.33%, (34.44 nm particle size) and 13.67% (18 nm particle size) and were then coated on Iranian natural CLI zeolite. The results indicated that the photocatalytic removal efficiency of the 9% Ni/TiO ₂ -CLI samples, in which the azo dye concentrations were 25 and 50 mg/L, was 93% and 79% at 160 min. In addition, the composition of the 9% Ni/TiO ₂ -CLI possessed the greatest removal rate difference of azo dye at the concentrations of 25 and 50 mg/L. Conclusion: Application of Iranian CLI as a substrate is the most cost-effective way to increase the photocatalytic activity. Furthermore, adding Ni to TiO ₂ can increase the photocatalyst removal efficiency of azonium compound.

Aims: The present study was conducted to identify Nocardia spp. from Iran soil by various phenotypic tests. Materials and Methods: A total of 300 soil samples were collected of five different geographical regions in Iran. Nocardia isolation was performed by paraffin baiting technique. The colonies that were similar to be Nocardia spp. were stained with Gram, partially acid fast and acid-fast. Phenotypic tests were used for identification of Nocardia spp. Results: After analysis of phenotypic tests, the identified species are as follow: Nocardia asteroides (49.12%), Nocardia cyriacigeorgica (24.56%), Nocardia otitidiscaviarum (38.6%), N. asteroides complex (19.29%), Nocardia africana (3.5%), and Nocardia pseudobrasiliensis, Nocardia coubleae, Nocardia ignorata (each species; 1.75%). In this study, some of isolates (8.77%) remained undetected. Conclusion: Due to great number of Nocardia spp., high similarities among biochemical characteristics of species and the variability of some these characters, a wide range of biochemical tests should be used to identify Nocardia spp. to gain more accurate results.

Aims: The aim of this study is Cr (VI) removal by titanium dioxide (TiO2) photocatalytic reduction and the effect of phenol and humic acid (HA) on its removal efficiency are investigated. Materials and Methods: The experiments were performed on both simulated synthetic wastewater and real wastewater. Various parameters such as pH, contact time, Cr (VI) and TiO ₂ concentrations, and a constant concentration of phenol and HA were considered to perform the experiments. Results: The removal value of Cr (VI) alone is 81% and in combination with HA and phenol is 89.7% and 96.2%, respectively. Cr (VI) removal efficiency was enhanced by decreasing pH and contact time. With increasing TiO ₂ dosage, the removal of Cr (VI) increased, up to 0.5 g/L and then decreased at 1 g/L. Cr (VI) removal efficiency decreases with the increase of Cr (VI) initial concentration. Removal efficiency, in 10 mg/L initial concentration of phenol and HA, was enhanced as contact time increased. Equilibrium data and adsorption process kinetics obey Langmuir isotherm model and pseudo second-order kinetic model, respectively. Conclusions: Heavy metal ions and organic pollutants are often present in real wastewater. This research suggests that the photocatalytic reaction TiO ₂ could be applied to more effectively treat wastewaters containing both Cr (VI) and organic compounds.

Aims: This work evaluated the surface and groundwater quality of Mohanpur area, Rajshahi district, Bangladesh. Multivariate statistical techniques were also applied to determine the possible sources of water contamination. Materials and Methods: Water samples were collected from randomly selected ten different sampling sites for analyzing the chemical parameters including pH, electrical conductivity, total dissolved solids, total hardness, total alkalinity, Cl⁻ , NO3⁻ and some heavy metals such as Mn, Pb, Cd, and As concentrations. Concentrations of heavy metals were determined using atomic absorption spectrometer (AAS). Results: Based on hydrochemical characteristics, surface and groundwater in the study area were, in general, fresh, hard, and alkaline in nature. All chemical parameters were within the WHO water quality guidelines. Whereas, among four analyzed heavy metals Pb, and Cd concentrations exceeded the WHO recommended values. Pearson correlation matrix showed a number of statistically significant associations (P < 0.01 and P < 0.05) among the examined water quality parameters. Moreover, principal component (PC) analysis (PCA) and cluster analysis (CA) were used to analyze the water quality dataset. PCA analysis identified two PCs as responsible for the data structure explaining 72.53% of the total variance in water quality. PCA indicated that the water quality variations were mainly of anthropogenic origin through agricultural and municipal discharges. Results of CA revealed three significant groups of similarity among the 10 sampling sites. Conclusions: It could be deduced from the present results that water contamination was occurred to some extent throughout the area, and is likely to be continued in the near future. Improvement of local sanitation system along with frequent training and awareness programs can help in developing water quality in the studied area.

Aims: The aims of this study were to monitor the concentration of benzene, toluene, ethyl benzene and xylenes (BTEX) in the ambient air of the city of Shahreza gas stations and to identify the spreading distance of the pollutants from the fueling stations. Materials and Methods: Sampling was carried out from the air of 10 existing fuel stations, (2 compressed natural gas and 8 gasoline and diesel stations) and points of 50, 150 and 250 m away from the stations during cold and warm seasons in 2013. Air samples were taken via active sampling process using activated carbon tubes, extracted by carbon disulfide and analyzed by a gas chromatograph coupled to a flame ionization detector. Results: The averages of all achieved BTEX concentrations were under/around the permitted guideline levels for occupational exposure. According to the ambient air guidelines, the benzene level was much higher than the suggested levels in all the stations. However, the average concentrations of toluene, ethyl benzene, and xylene were not exceeded from the standards. The seasonal variation had no influence on the concentrations of BTEX. There was no significant difference between the pollutants concentrations at points 50, 150 and 250 m away from the stations. Conclusions: Fuel stations could be the main sources of volatile organic compounds emission in the city of Shahreza. The number and volume of refueling in the gas stations influence the emission rates. Therefore, it is suggested to take preventive actions such as repairing of pumps and tanks leak and installing vapor return systems at the time of fuel transferring.

Aims: The objectives of this study were to determine the perchlorate concentrations in surface soils and assess feasibility of anaerobic bioremediation in full-scale for perchlorate-contaminated soils in a war zone. Materials and Methods: Fifteen samples of surface soil were collected using a composite sampling method in the study area. The soil samples, after extraction and preparation, were analyzed by ion chromatography. Anaerobic composting technique (soil excavation, mixing with manure, transfer into treatment cell and cover with a 6-mil high-density polyethylene liner) considered to cleanup perchlorate-contaminated soil in a war zone. Results: The concentration of perchlorate in the soil surface samples ranged from 3 to 107.9 mg/kg, which is more than State advisory levels for residential and protection of domestic groundwater use pathway. This study indicates that technologies, skills, experience, raw materials (manure), lands, and machinery needed for implementation of full-scale composting, are available in the study area. Conclusions: Based on the results, anaerobic composting technique could be considered as a feasible, viable and cost-effective alternative for perchlorate bioremediation in the study area. According to the available of techniques and skills, successful experiences of anaerobic composting in other countries, and potential of study area, The application of anaerobic composting is technically feasible and can be use for perchlorate contaminated soil cleanup in a zone war.

Aims: This study aimed to assess the microbial contamination status of drinking water supply among buses at the main bus terminal in Isfahan. Materials and Methods: About 184 drinking water samples were taken randomly from buses arriving at the Sofeh terminal in Isfahan in 2011. For data analysis of one-sample, Kolmogorov-Smirnov test (α = 0.05).and Mann-Whitney U-test with a significant difference (α = 0.05) was used for the effect of setting insulated water tank in cities bus to reduce microbial contamination. Results: Results showed that 15% of all samples were contaminated with total coliforms and 2.5% of samples contaminated with fecal coliforms. The most contaminated samples were related to buses arriving from Shiraz and Booshehr, (fecal MPN~4). About 16.66% of all samples collected from buses without insulated water tanks were contaminated with total coliforms and fecal coliforms. Conclusion: Results indicated that the drinking water available on investigated public transportation was not safe for public health. However, the highest levels of microbial contamination were observed in samples taken from buses without insulated water tanks. In conclusion, a constant and systematic monitoring system is recommended to prevent contamination of drinking water available on buses.

Aims: The present study aimed to evaluate the assessment methods of human errors and compare the results of these techniques in order to introduce the precise method of human error assessment, and recognize the factors affecting the occurrence of these errors. Materials and Methods: This case study was done at three workstation control room of a cement industry in 2014. After determining the responsibilities and critical jobs by hierarchical task analysis, cognitive reliability and error analysis method (CREAM) and human error assessment and reduction technique (HEART) were used in order to analyze the human errors. Results: The results showed that in the CREAM method, the highest probability of error occurrence is related to monitoring and control (operator) with a probability of 0.207, and that of in the HEART method, is related to control signs (operator) with a probability of 0.416. The number of errors detected by CREAM and HEART method were 85 and 80, respectively. Time and cost of applying the CREAM methods were 235 h and 1175($), while those in the HEART techniques were 215 h and 1075($). Conclusion: We concluded that the highest probability of calculated errors relates to "monitoring and control (operator)," "controlling warning signs (operators)," and "cooperation in solving the problem (supervisor)" for both techniques. By considering the time and cost factors, HEART has superiority, while CREAM is better due to its extensive evaluation and the number of detected errors.

Aims: In this study, management of industrial waste in industries located between Tehran and Karaj in 2009-2010 was examined. Materials and Methods: This is a cross-sectional study which was done by site survey (Iranian environmental protection organization) questionnaire usage and results analysis. This questionnaire was consisted of 45 questions about industrial waste, quantity, quality, and management. A total number of industries with over 50 employees was 283, and Stratified sampling method was used. Sample of size 50 was selected from 283cases. Results: The major hazardous waste-generating industries include chemical and plastic. Private sectors disposed 45% of generated waste. Majority of wastes were buried (62%), and only 17% of industrial waste was recycled. Conclusion: For hazardous waste reduction in this zone and health and economic attractions, the opportunity for reuse and recovery for these wastes must maximize in short-term and burial of industrial waste must be minimized. Industries such as chemical-plastic and electronics which have higher hazardous waste, in long-term, must be replaced with other industries such as wood cellulose and paper that have lower hazardous waste production rate.

Aims: The aim of this study was to investigate the geographical pattern of stomach cancer and its probable link to heavy metal concentration high-risk area of Kurdistan, Iran. Materials and Methods: This descriptive-analytical study analyzed the deaths due to cancer over a period of 2006-2010. The data were collected from health deputy of Kurdistan province. Spatial distribution map of cancer was prepared using geographic information system software. Finally, the distribution map of heavy metals that could be related to stomach cancer was provided. Results: The spatial distribution maps of stomach cancer mortality shows that the highest mortality rate for the stomach cancer was identified in Divandareh, Bijar and Saghez cites. These cities have shown high concentration of heavy metals. Overlaying the map of stomach cancer via distribution of heavy metals in mineral deposits shows that lead, arsenic and antimony concentration in the city were higher density and can lead to stomach cancer. Conclusions: This study showed that the death rate related to cancer in men and rural area was higher than women and urban area. In addition, the statistical analysis showed a high correlation between gastric cancer and living in the area with mineral deposit of lead, arsenic and antimony.

Aims: The aim of this study was the performance evaluation of ultrafiltration (UF) membrane process as an advanced treatment to secondary effluent quality improvement in Isfahan - Morchekhort Industrial Estate wastewater treatment plant. Materials and Methods: Membrane system used in this study included a flat sheet UF module of polysulfone with 0.1 μm pore size. The coagulation, flocculation and sedimentation (Coag, Floc, Sed) and rapid sand filtration in conjunction with granular activated carbon (GAC) filtration was used as pretreatment of secondary effluent. All test methods was obtained of standard method for the examination of water and wastewater. Results: The membrane system could decrease turbidity, chemical oxygen demand (COD), total suspended solids (TSS), total hardness (TH), total coliform (TC), fecal coliform (FC), total nitrogen (TN) and Cl⁻ , 24.5, 19, 48, 10.5, 94.5, 85.1, 15.4 and 1.01%, respectively. Conclusion: UF was able to improve chemical parameters of secondary effluent and meet national environmental standards. However, achievement to optimum operation of this system requires adequate pretreatments such as adding filter aid, sand filtration and GAC. The most part of suspended particles expressed by turbidity was removed within UF membrane, whereas only a little of organic substance expressed by COD or color and salt expressed by conductivity could be removed.

Aims: In this study, removal efficiency of linear alkylbenzene sulfonate (LAS) in Stabilization pond plant was investigated. Materials and Methods: In this study, 64 samples were taken for 1-year in stabilization pond plant of Yazd city, central of Iran, in 2010. The samples were analyzed according to the standard methods. Methylene blue active substances were used to determine the amount of anionic surfactants. Results: The most removal efficiency of anionic surfactants occurred in secondary facultative stabilization pond in summer and the least removal efficiency of anionic surfactant in anaerobic stabilization pond in the autumn was obtained. Conclusion: According to the environmental standards for discharge of treated wastewater to the surface water, agricultural water usage and discharge to absorbent wells with P < 0.5 have significant difference values are more than standards.

Aims: In this study, the health impacts of SO2 in three cities, including Ahvaz, Kermanshah and Boushehr was quantified and compared based on modeling using data from Department of Environment (DoE) in 2011. Materials and Methods: Required data were collected from DoE and Meteorological Organization. Later, data were processed by Excel software and entered into AirQ Model; this model is identified by the World Health Organization. The processes include: Correction of temperature and pressure, matching the unit with the model. Results: Results from three study areas showed that SO ₂ concentration in Kermanshah city with the annual average of 103 μg/m ³ and in Boushehr city with 44 μg/m ³ was the highest and lowest in 2011, respectively. In all three cities, 8% and 1% increase in risk of cardiovascular and respiratory mortality was observed, respectively, per 10 μg/m ³ increased in concentration of SO ₂ . Conclusion: About 60% of cardiovascular deaths attributed to SO ₂ in ambient air of Ahvaz occurred in days with pollutant not exceeding 90 μg/m ³ , whereas 46% and 41% of this health end point occurred in days with sulfur dioxide concentration not exceeding 190 μg/m ³ and 100 μg/m ³ in ambient air of Kermanshah and Boushehr, respectively. In comparison, Kermanshah and Boushehr were the highest and lowest in view of cardiovascular and respiratory mortality attributed to SO ₂ concentration in 2011, respectively.

Aims: The concentration of Cd, Cr, Al and Pb present in inhalable air and deposited dust in a metal-mechanical parts manufacturing plant in Puebla, México were determined in order to assess the occupational exposure of workers in this plant. Materials and Methods: Fourteen air samples, six from the metal welding (MW) and eight from the metal forming (MF) areas, as well as metal dust accumulated on the floor of an auto part manufacturing plant, were collected. Sampling and analysis followed the National Institute for Occupational Safety and Health (NIOSH) recommended methods for metals in inhalable air. Results: The average concentration of Al and Cd determined in a volume of inhalable air were adequate under NIOSH maximal exposure concentration limits in both sampled sites. Average concentrations of 0.001 (MF sampling site) and 0.105 μg/L (MW sampling site) for Al; 0.003 (MF) and 0.0005 (MW) μg/L for Cd, with respect to the NIOHS limits, 10 and 0.005 μg/L, for Al and Cd, respectively. However, Cr and Pb concentrations exceeded or were close to the limits recommended by NIOHS in both places (0.5 and 0.05 μg/L for Cr and Pb, respectively). Average concentrations of 0.345 (MF) and 0.77 (MW) μg/L for Cr and 0.153 (MF) and 0.649 (MW) μg/L for Pb, were determined. Levels of metal content (Cd, Cr and Pb) in powder samples collected in both sampling sites were also higher than the suggested limits. Conclusion: The average concentration of Cr and Pb exceeded the limits recommended by the Occupational Safety and Health Administration and NIOSH for inhalable air in the workplace. Workers may be on risk of heavy metal occupational exposure. It is endorsed to implement safety measurements to avoid the breathing of contaminated air and also industrial level systems for dust and aerosol particle filtering or precipitation, altogether with stricter policies to regulate heavy metal exposure at these industries.

Aims: This study investigates the potential of chitin shrimp shells for the removal of arsenic (V) and zinc (II) ions from aqueous solutions. Materials and Methods: In this study, the chitin was extracted from shrimp shells for arsenate and zinc ions removal from aqueous solutions. The effects of pH, adsorbent dosage, contact time and initial metal ion concentration on As (V) and Zn (II) removal were investigated in a batch system. Results: The equilibrium data were described using the Langmuir and Freundlich isotherm models. The Langmuir equation was used to find the maximum adsorption capacity for arsenate (11.574 mg/g) and Zn (270.27 mg/g). Biosorption was found to depend significantly on the pH of the solution and is optimal at pH values of 4 and 7. To determine the rate-controlling mechanism for metallic ion adsorption, pseudo-first-order and pseudo-second-order equation kinetic models were tested with experimental adsorption kinetic data. Modeling results revealed that As (V) and Zn (II) kinetics data were successfully described using pseudo-first and second-order models, respectively. FTIR analyses showed that hydroxyl and carboxyl groups could be very effective for capturing these metals. Conclusion: Results showed that the chitin is a good adsorbent for the removal of arsenate and zinc ions from aqueous solutions.

Aims: The main goal of this paper was to evaluate the effectiveness of Helmholtz resonator in noise reduction of duct equipped with active noise control (ANC). Materials and Methods: Noise frequency band was produced by a propeller fan, which was spread into a plexiglas duct. The noise was formed by digital signal processing (DSP) to estimate the anti-noise which spreads along the duct to postpone the primary noise as a response to DSP. In this method, fan noise was recorded with a microphone. The anti-noise with the same amplitude was reproduced, and the reverse phase postpones the original noise at the primary noise path by a speaker. The designed Helmholtz resonator was installed on the duct for detecting the reduction noise at the tonal interest frequency of 300 Hz. Helmholtz resonators can give sound attenuation at a narrowband of frequencies, close to its resonance frequency. The overall decline changes were estimated in order to predict the effectiveness of the method. Results: In this study, a noise discount of 5-10 dB at the peak frequencies has been observed. The peak frequency of residual noise has reduced 5-10 dB. The value is more than applying ANC system solely to optimize noise lessening of produced noise by a fan along the designed duct. Conclusion: Use of Helmholtz resonator is proposed as a suggestion to optimize the process of noise fall in duct. This study is concerned with the attenuation of tonal noise transmission in ducts by using ANC and side branch resonators together.

Aims: The main purpose of this study was to determine the efficiency of a sequencing treatment including ultraviolet (UV)/H ₂ O ₂ oxidation followed by a moving bed bioreactor (MBBR). Materials and Methods: Effect of solution pH, reaction time, and H ₂ O ₂ concentration were investigated for an industrial wastewater sample. The effluent of the advanced oxidation processes unit was introduced to the MBBR operated for three hydraulic retention times of 4, 8, and 12 h. Results: The optimum condition for industrial wastewater treatment via advanced oxidation was solution pH: 7, H ₂ O ₂ dose: 1000 mg/L and 90 min reaction time. These conditions led to 74.68% chemical oxygen demand (COD) removal and 66.15% biochemical oxygen demand (BOD ₅ ) removal from presedimentation step effluent that initially had COD and BOD ₅ contents of 4,400 and 1,950 mg/L, respectively. Conclusion: Combination of UV/H ₂ O ₂ advanced oxidation with MBBR could result in effluents that meet water quality standards for discharge to receiving waters.

Aims: This study was aimed to determine the TiO ₂ /zeolite photocatalytic activity for removing red Safranin dye form aqueous phase. Materials and Methods: In this study, TiO ₂ nanoparticles were produced using sol-gel method and 2.5 ml sol-gel was coated on 1.2222 g of zeolite. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were applied to specify the structure and morphology of TiO ₂ nanoparticles. The effect of TiO ₂ coating on zeolite, ultraviolet (UV) radiation intensity, initial concentration of dye and the type of photocatalyst substrate (fixed and moving) on photocatalytic process was investigated. Results: According to XRD results, the TiO ₂ nanoparticles had two phases including anatase (80.5%) and rutile (19.5%). The uniformity of nanoparticles was obvious in the SEM images. The removal efficiency of TiO ₂ coated on zeolite was higher than TiO ₂ photocatalysis with increasing UV radiation intensity from 2.4 w/m ² to 3.9 w/m ² , the photocatalytic efficiency was also enhanced. The removal efficiency decreased from 91.61% to 77.91% by increasing the red Safranin dye concentration from 10 mg/L to 50 mg/L. The moving bed of TiO ₂ /zeolite photocatalyst had a higher efficiency than the fixed bed. Conclusion: In over all, the TiO ₂ /zeolite photocatalyst was much more effective than TiO ₂ photocatalyst for Safranin dye removal from the aqueous phase. With increasing UV radiation intensity and decreasing dye concentration photocatalytic efficiency, was improved. TiO ₂ /zeolite photocatalyst with fixed bed is recommended to be used in water treatment. The most important problem of using moving-bed TiO ₂ /zeolite photocatalyst in the water treatment is opacity.

Aims: The aims of this study were to analyze the carbon, hydrogen, nitrogen, sulfur, and oxygen (CHNS-O) content of compost derived from Isfahan-Iran municipal solid waste using thermal elemental analyzer and to develop an approximate empirical chemical formula for the organic fraction of the mature compost as a function of its elemental composition. Materials and Methods: The compost samples (1 kg) were collected from different parts of the windrows and thoroughly mixed in accordance with standard methods. After drying and milling, each sample was introduced to an elemental analyzer to measure their CHNS-O contents. The moisture content, temperature, and pH value were also monitored in three different windrows during the process. Results: An approximate chemical empirical formula calculated for the organic fraction of the compost was: C ₂₀₄ H ₃₂₅ O ₈₅ N ₇₇ S. Conclusion: According to this formula, it appears that the mature compost produced in the site contains higher value of nondegradable nitrogen, which leads to a lower total C/N ratio. Therefore, improving the primary separation of raw material in the composting plant particularly severance of plastic materials can result in an optimum C/N ratio.

Aims: The aim of this study was to evaluate the relationship between environmental and physiological heat stress indices based on heart rate (HR), oral temperature for the estimation of heat strain, in veiled women in hot-dry condition in the climate chamber. Materials and Methods: The experimental study was carried out on 36 healthy Muslim women in hot-dry climatic conditions (wet bulb globe temperature (WBGT) = 22-32°C) in low workload for 2 h. The HR, oral temperature and WBGT index were measured. The obtained data were analyzed using descriptive statistics and Pearson correlation tests. Results: The results of the Pearson test indicated that physiological strain index was a high correlation (r = 0.975) with WBGT index (P < 0.05). Also, there was a good correlation among WBGT and HR (r = 0.779) and oral temperature (r = 0.981). Conclusion: The findings of this study illustrated that there is a good correlation between environmental and physiological heat stress indices in veiled women with Islamic clothing at the low workload over the action limit (WBGT = 31°C). So that it can be concluded that the WBGT 22-32°C is a good indicator of the heat strain in veiled women with Islamic clothing.

Aim: The study aimed to assess the prevalence of Listeria spp. in raw milk and traditional non-pasteurized dairy products in Isfahan, Iran. Materials and Methods: A total of 292 samples of raw milk and traditional dairy were examined for the presence of Listeria spp. using a two-step selective enrichment recommended by the United States Department of Agriculture. All isolates were subjected to standard biochemical tests. L. monocytogenes strains were further confirmed by polymerase chain reaction (PCR) amplification. Results: Of 292 samples, 21 (7.14%) and 4 (1.47%) were positive for Listeria spp. and pathogenic L. monocytogenes, respectively. The prevalence of Listeria spp. in raw milk, ice cream, cream, and freni were 5.91 (5.49%), 12.63 (19.04%), 3.27 (11.11%) and 1.25 (4%), respectively. Listeria was not detected from yogurt, butter, Kashk, and cheese. Listeria innocua at 16.21 (5.44%) was the most prevalent species isolated, followed by L. monocytogenes at 4.21 (19%) and L. seeligeri at 1.21 (4.7%). All strains of L. monocytogenes identified by biochemical tests were also confirmed by PCR. Conclusion: The study shows the prevalence of L. monocytogenes in raw milk and traditional dairy products sold in the market. Consumption of raw milk with mild heat treatment or its usage in traditional dishes could pose serious health problems due to lack of appropriate control measures. The lack of knowledge on the risks of listeriosis transmission indicates the need for implementation of a food safety education program. In addition, the Iranian food safety authorities should urgently set up an effective standard to screen all susceptible food products for the presence of Listeria.

Aims: The purpose of this study was to compare performance of two these WBGT measuring devices. Materials and Methods: This study was performed in the climatic chamber located in Health School of Isfahan University of Medical Science. The WBGT _Casella and the WBGT _{Model 686} were placed a wide range of hot/dry (28.5-38.5°C) and hot/wet conditions (25.9-37.7°C) in 3 air flow velocity (0.16, 0.27, 0.31 m/s) for 10 h in the climatic chamber. Wet bulb temperature (t _nw ), the dry temperature (t _a ), the globe temperature (t _g ) and the WBGT were measured every 3 min for both instruments in the total period. The data obtained were analyzed by descriptive method, T-paired test and Regression analysis. Results: The result of this study showed that there were statistically significant differences in the meteorological parameter (t _nw , t _a , t _g , WBGT) obtained from the WBGT _Casella and WBGT _{Model 686} (P < 0.001). A high correlation also was seen between the values obtained by the WBGT _Casella and the WBGT _{Model 686} (r = 0.993). Furthermore, there were statistically significant differences in the air flow velocity parameter (0.157 m/s) and (0.27 m/s) and (0.314 m/s) in a hot/dry (r = 0.994) and (0.980) and (0.994) respectively. There were statistically significant differences in the air flow velocity parameter (0.157 m/s) and (0.27 m/s) and (0.314 m/s) in a hot/wet (r = 0.980) and (0.992) and (0.973) respectively. Conclusion: Since there is a high correlation between the values recorded by two devices and a remarkable cost - efficacy of WBGT _{Model 686} , using WBGT _{Model 686} is an acceptable method for measuring the heat stress if the prediction equations are utilized. According to the different temperature conditions, was obtained dry temperature, wet temperature and globe temperature both devices measurement in different climatic conditions equation WBGT _Casella = 2.04 + 1.03 (WBGT _{Model 686} ). About 2 units WBGT _{Model 686} lower than the WBGT _Casella and recommend the measures to be considered in this case as well as the manufacturers also, recommend doing that the reform of sensor measurements and the calculation methods.

Aim: This study was carried out to investigate the quality of Mobarakeh ambient air in terms of suspended particles and heavy metals. Material and Methods: The current study was carried out in Mobarakeh city, Isfahan, Iran. Air sampling was performed in three sites for a 1-year period (in 2007). Measurement of total suspended particles (TSP) and heavy metals was achieved using high volume air sampler with fiberglass filter. The concentration of heavy metals, including Pb, Ni, Zn, Fe, and Cu was measured by atomic absorption spectrometry. Results: The average concentration of TSP was maximum and minimum in autumn and spring, respectively. In addition, the average of annual TSP concentration (124.61 mg/L) was more than World Health Organization (WHO) and US Environmental Protection Agency standard values. The analysis of filtered suspended particles for heavy metals showed the highest concentration for Iron. The average annual concentration of Nickel was also more than its proposed standard by WHO. Conclusion: This study showed that ambient air of Mobarakeh city is polluted by TSP. The high concentration of Fe and Ni in this area may be attributed to the nearby industrial emissions. Therefore, in industrial areas, efforts should be taken to control the atmospheric pollution in order to protect humans from hazardous health effects of these potentially toxic pollutants.

Aims: In accordance with the Air Clean Act developed for ozone monitoring, the measurement of volatile organic compounds (VOCs) based on photochemical assessment monitoring stations (PAMS) was carried out. Materials and Methods: Thirteen species of VOCs were measured on Enghelab square in Tehran by PhoCheck PID Detector at morning, noon, and afternoon for 3 months. The data were reported as descriptive statistics. Results: Most of the VOCs species showed diurnal variations with higher concentrations in the noon. The highest concentration of VOCs was aromatic group (AR: 0.549 ± 0.146 ppb). AR was the main contributor to photochemical smog. Conclusion: The majority of the AR class and toluene may be followed by the impacts of heavy traffic and the peak values of VOCs concentrations occurred around mid-day which depends indirectly upon vehicles and emission of evaporations.

Aim: The purpose of this study was to evaluate the concentrations of toluene and ethylbenzene inside the cars with an interior source related to in-cabin decoration and deodorizer use among Pride cars manufactured in Iran. Materials and Methods: The vehicles under study were Pride cars manufactured in Iran. In-cabin sampling was conducted by a personal sampling pump drawing air through an active carbon sorbent tube. The samples were analyzed by a gas chromatograph equipped with mass spectrophotometer detector. Results: In - cabin mean concentrations of toluene and ethylbenzene were 105.4 μg/m ³ and 19.09 μg/m ³ , respectively. The effects of decoration and deodorizer use inside the cars on toluene and ethylbenzene in-cabin concentrations were also not significant. Conclusion: Total means concentration of toluene inside the cars was higher than that of ethylbenzene. Models of the studied vehicles were not significantly affecting the concentrations of the target volatile organic compounds.

Aims: The purpose of this article was investigating the efficiency of designing resonator in decreasing low noises. Materials and Methods: The designed Helmholtz resonator was installed in a channel analogous to ventilation channel. The resonator was produced signals at very low frequencies (125-500 Hz) and sound pressure levels 60-90 dB and transmitted through a channel by means of a speaker. Afterwards, the variation of sound pressure level was monitored and then intra-channel signals processing and preparing of sound Algorithm in channel was done by MATLAB software. Results: The highest decrease of sound pressure level at 125 Hz frequency among of Helmholtz resonators was observed at chamber diameter of 63 mm and resonator's 1 cm-caliber. Sound pressure level reductions of 0-10 dB were achieved in an experimental duct system using a Helmholtz resonator. Conclusions: This research showed that the designed Helmholtz resonators at a certain frequency of low-frequency sound demonstrated the soundest decrease. The increase in the Helmholtz resonators' chamber volume and their neck's pass area are negatively associated with the rate of sound resonance. As a result, of determining the effective frequency range of the Helmholtz resonator, the designed resonator could be applied as an effective and efficient instrument of removing or decreasing noise.

Aims: In this study, the turbidity removal efficiencies of poly-aluminum chloride (PACl) and poly-aluminum chloride-sulfate (PACS) as a coagulant in aqueous solutions were compared. Materials and Methods: PACS and PACl were prepared at experimental conditions. A conventional jar test apparatus was used for coagulation experiments. Effects of different conditions such as pH (2-12), coagulant doses of PACl (0.01-1.5 mmol/L as Al) and PACS (0.01-1.8 mmol/L as Al), settling time (0-90 min), initial turbidity (7-575 NTU) on the turbidity removal efficiency were investigated. Results: The experimental results indicated that the optimum pH during the turbidity removal was 6.5 and 9.5 for PACl and PACS, respectively. The optimum coagulant dosages of PACl and PACS were achieved 0.1 and 1.22 mmol/L as Al respectively. Under these optimal conditions, the turbidity removal efficiencies of 97.85% and 95.85% were observed for PACS and PACl, respectively. Furthermore, the effects of settling time and initial turbidity on turbidity removal efficiency were investigated. The results revealed that the turbidity removal efficiency for the PACS was slightly higher than that for PACl at the same conditions. Conclusion: PACS as a coagulant improved turbidity removal efficiency compared to PACl. PACS as a coagulant can be used for drinking water treatment. However, the dosage of PACl in comparison with PACS was lower for a similar turbidity levels. Therefore, using of PACS in comparison with PACl must be evaluated economically.

Aims: The aim of this study was to evaluate the photocatalytic processes for cadmium (Cd ²⁺ ) and lead (Pb ²⁺ ) removal at continuous and batch system. Materials and Methods: This study was performed at laboratory scale. The reactors used in this study consisted of three parts: Ultraviolet (UV) source, reaction cell, and mixing chamber. The experiments were carried out in a batch and continuous reactor for synthetic wastewater. The concentration of Cd ²⁺ and Pb ²⁺ was constant (25 mg/L) in all experiments and effect of titanium dioxide (TiO ₂ ) dose, pH, and air dispersion was investigated on the removal efficiency. Results: The results showed that with increasing TiO ₂ dose and pH, the cadmium and lead removal increase. The maximum removal of cadmium and lead was obtained in TiO ₂ dose 0.9 g/L and pH: 11 that were equal to 99.8 and 99.2% respectively. Furthermore, when air dispersion increased, the removal efficiency increased; while in the air dispersion 2 cm ³ /L the removal efficiency was maximum (88 and 93.2% at the contact time 56 min for Cd ²⁺ and Pb ²⁺ , respectively). Conclusion: According to these results the TiO ₂ has been considered as photocatalyst is the separable and recyclable, so UV/TiO ₂ process is an environment friendly process for toxic metal removal.

Background: Road traffic crashes are a huge public health and development problem in Ethiopia. Its current situation requires a high level political commitment, immediate decisions and actions in order to curb the growing problem. Materials and Methods: Data on fatalities, total and partial permanent injuries, and lost workday attributable to vehicle crashes were collected from North Gondar Traffic Offices from 1996 to 2011. Holt and Brown exponential smoothing techniques were used to model the number of fatalities and other injuries due to vehicle crashes. Results: There were 2300 vehicle crashes that occurred from 1996 to 2011 causing an estimated 968 fatalities, 1665 lost workday and 1185 permanent total and partial injuries, and 1,899,950.60$ losses. Only 7.6% of the vehicles had problems before the crashes occurred while 89.9% had no problems. The mean time of crashes occurred were 12.78 h with a standard deviation of 4.19 h. The highest daily, monthly, seasonal, and yearly crashes occurred were during Friday, January, winter and 2009, respectively. Future forecasts showed that by 2015, there could be 414 fatalities, 1123 lost workdays and 438 permanent total and partial injuries, and 955,249.12$ losses. Conclusion: The numbers of lives lost and disabilities due to vehicle crashes indicated an upward trend in the last decade showing future burden in terms of societal and economic costs threatening the lives of many individuals. Surveillance systems that could enable to monitor patterns of vehicle crashes with preventive strategies must be established.

Aims: The aim of this study is to determine the impact of relative humidity (RH) and contaminant concentration on photocatalytic conversion of gaseous toluene by using TiO ₂ coated on nickel foam. Materials and Methods: TiO ₂ nanoparticles were prepared by the sol-gel process and coated on nickel foam. Structural and morphological characteristics of nanoparticles were determined using Scanning electron microscope, X-ray diffraction analysis. Photocatalytic conversion of gaseous toluene at the different levels of RH and toluene concentration was measured under ultraviolet-A radiation by gas chromatograph with Flame Ionization Detector. Results: After being fixed the contaminant concentration, 30% level of RH had the most impact on the photocatalytic efficiency, 10, 0,5 0 and 80% levels of humidity had, in turn, the most impact. Results also showed that TiO ₂ nanoparticles coated on nickel foam at the concentration of 20 ppm had the most efficiency of photocatalytic conversion. After that, the most efficiency was recorded at the 10 and 50 ppm concentrations, respectively. Conclusion: Based on the results, the photocatalytic conversion of gaseous phase toluene by TiO ₂ coated nickel foam is increased with the increase of RH to a certain level; beyond that the conversion efficiency is decreased gradually due to the saturation of photocatalyst surface and decrease in nanoparticle activity. Furthermore, photocatalytic conversion of gaseous toluene is decreased with the increase of toluene concentration.

Aims: The purpose of this study was to determine of nitrate and nitrite exposure and their health risk assessment in 21 brands of bottled waters in Isfahan's market in 2013. Materials and Methods: The samples bought from shops in Isfahan city and were analyzed for nitrate and nitrite. The measured concentration of nitrate and nitrite were compared with the labeling data and codex guideline values. Statistical analysis on data was performed with the Kolmogorov-Simonov non-parametric test, the paired t-test and the student's t-test at P < 0.05 of confidence level. The health risk was assessed through chronic daily intake (CDI) and hazard index (HI). Results: The mean concentrations ± standard deviations based on statistical t-test for nitrate and nitrite were 1.42 ± 0.55 and 0.02 ± 0.015 mg/l, respectively. Based on results nitrate concentrations have a statistically significant difference with labeling values. There was no labeling value for nitrite on the samples. The amounts of CDI for nitrate and nitrite were 1.5E-04 and 3.3E-04 mg/kg/day, respectively and their related HI was same and below 1. Conclusion: According to the results of the present study, nitrate and nitrite levels in the studied bottled waters were not found in concentrations considered hazardous in terms of public health. The label values not provide reliable data for consumer. The health risk of bottled water consumers from nitrate and nitrite exposure in Isfahan were in the acceptable range.

Aims: The aim of this study was to compare the concentration of volatile organic compounds in administration rooms of the hospital. Materials and Methods: The present study assessed indoor concentration levels benzene, toluene, ethyl benzene and xylene (BTEX) in eight hospitals of Yazd province from January 16 to February 25 of 2012. Management, accounting and personnel rooms were selected as sampling units. Samples collected in three sequential daytimes by Tedlar bag. Gas chromatography-flame ionization detector method was applied for analysis of the component. Results: Total BTEX concentrations were relatively below (<10 μg/m ³ ) in all hospitals. There was no significant difference in amounts of the compounds among studied parts, except for benzene (P < 0.05). According to sampling units, the mean of BTEX component concentrations (in units of μg/m ³ ) were for benzene 1.03 ± 1.21, toluene 0.96 ± 1.79, ethyl benzene 0.78 ± 1.92 and xylene 0.86 ± 0.73, respectively. Conclusion: The accounting unit showed highest concentrations of BTEX that its possible due to usage of the numerous numbers of electronic devices (computers, printer and copier), official supply (ink varnish, adhesive, etc.) and the air-conditioner.

Aims: The aim of this study was to determine water softening behavior of Iranian natural zeolite and blast furnace slag (BFS) as materials of slow sand filters (SSFs) in small communities' water resources. Materials and Methods: Three filters setups were prepared from the plexiglass tubes each by 9 cm inner diameter and 120 cm height. The used filter media were included conventional sand, BFS and Iranian natural zeolite. The filtration rate was adjusted between 0.1 and 0.24 m ³ /m ² /h and hence that the flow rate of each filter was 1.5 L/h. Turbidity, total hardness and EC of water samples were analyzed before and after the treatment process according to standard methods. Results: The mean turbidity removal efficiencies in the studied filters were 98.82%, 98.98% and 98.97% for conventional SSF, slag modified filter (SMF) and zeolite modified filter (ZMF), respectively. The mean EC reduction efficiencies in SSF, SMF and ZMF also were similar and were 9.99%, 11.02% and 10.73%, respectively. The mean total hardness removal efficiencies in SSF, SMF and ZMF were 21.19%, 51.95% and 66.3%, respectively. Conclusions: It is concluded from this study that modified filter media, SMF and ZMF, are very good options for total hardness and turbidity removals in communities that have some problem with this parameter.

Aims: The object of this study was to assess the usefulness of the H ₂ S test for detection of fecal pollution of water in comparison to fecal indicator bacteria (FIB). Materials and Methods: A total of 70 raw water samples were collected from drinking water sources in Isfahan province of Iran, aseptically in sterile containers during May-October 2012.The modified H ₂ S test medium of Manja et al. was used except that L-cysteine was added as an additional medium component. Total coliforms (TCs), fecal coliforms (FCs), and fecal streptococci (FS) were also estimated by multiple-tube fermentation method. Statistical analyses were carried out using SPSS 20 at the 95% confidence level (α = 0.05). Results: It was found that out of 70 water samples assessed, 48.3%, 30.0%, 34.6%, and 32.9% of the samples were positive for TCs, FCs, FS, and H ₂ S, respectively. Analysis of data showed that 95.6%, 69.5%, and 76.9% of water samples, which were positive for H ₂ S test were also positive for TCs, FCs, and FS, respectively. The H ₂ S test was found to have the highest accuracy for the detection of FS, but it was not a suitable indicator for the prediction of FCs. Conclusions: Our results showed that H ₂ S test is not a suitable alternative approach for routine water quality monitoring. However, the H ₂ S test could be used as an easy and economic test to assess the quality of drinking water in communities where manpower and sophisticated equipment are inadequate. More laboratory and field studies are required to assess the reliability of the method as an alternative method of traditional indicators.

Aims: The aim of this study was to find out the vulnerability of school children affected by roadside vehicle noise. Materials and Methods: The noise levels were measured in three time zones: 10.45 and 11.45 am, 12 and 1 pm, and 2 and 3 pm. A self-made interview schedule was constructed for getting feedback from the teachers and students about the problems associated with the teaching - learning process. The different percentile values L _10, L ₅₀ , L ₉₀ were used for the evaluation of noise climate (NC), equivalent noise level (Leq), transport noise index, and noise pollution level (L _NP ). Results: The results revealed that the average distance of the roadside school situated in urban area (9.4 feet) was much less than in rural area (14.4 feet). The average number of vehicles in rural areas was much less than in urban areas. The study also demonstrated that out of five varieties of vehicles, only heavy vehicles like bus and trucks produce intense noise (85-90 dB). Although air siren of train has a very high noise, which range from 90 to 115 dB, other varieties of light vehicles also produced noise ranges from 76 to 90 dB. The average noise meter reading clearly indicates that lesser the distance from the roadside, higher is the noise intensity. Conclusion: Results revealed that not all schools, particularly those schools that are very close to the roadside, are intensely affected by such high pitch noise and subsequently teaching - learning process were also greatly affected by such activities. Therefore, it is highly recommended that village committee and municipality authority should coordinate with the school authority for taking measures for such irreversible damaged.

Aims: The study was done to find out the types of injuries, modes of road traffic accidents and case fatality rate of road traffic accident cases from 1 ^st April 2005 to 31 ^st March 2010 in a tertiary care hospital. Materials and Methods: The retrospective study conducted on hospitalized patients admitted with road traffic accidents in a tertiary care level from 1 ^st April 2005 to 31 ^st March 2010. Data collected from the registers maintained in the medical records department, follows the guidelines of International Classification of Diseases-10 coding. Results: Of the 7,660 road traffic accident cases reported in a hospital from 1 ^st April 2005 to 31 ^st March 2010. Most of the cases and deaths were occurred in the age group of 15-44 years. Total deaths occurred due to road traffic accident was 249 (3.25%). Motorcycle rider injured in road traffic accident was more except other land transport accidents during the period from 2005 to 2010. Of the road traffic accident cases, fractures (42.7%) were more than superficial injuries (18.56%) and dislocations (2.6%). Conclusion: This study mentioned that most of the cases and deaths were occurred in 15-44 years. Accidents of the economically productive people will affect their family. Hence to reduce the road traffic accidents by conducting public awareness program and strict enforcement of traffic rules.

Aims: The aim was to study the indoor air quality (IAQ) levels inside the governmental elementary schools of Dammam City in Kingdom of Saudi Arabia (KSA) and study factors affecting these levels. Materials and Methods: Sixteen schools were selected for this study; 12 of them were representing governmental constructed buildings, while the other 4 schools were representing rental buildings. Levels of dust or total suspended particulates (TSP), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen dioxide (NO ₂ ), sulfur dioxide (SO ₂ ), and benzene; in addition to temperature degree and relative humidity percent were measured during this study at four selected locations inside each school and one location outside it. Results: The highest levels of all pollutants were found inside classrooms that were located directly on the moderate traffic streets compared with low or very low traffic activity ones. Levels of most air pollutants inside the governmental constructed buildings were higher than those inside the rental type of schools. Conclusion: The average levels of TSP, NO ₂ and CO inside all selected schools were lower than the air quality guidelines (AQGs). In contrary, all mean levels of CO ₂ and nearly 50% of SO ₂ and benzene levels were higher than their AQGs. Increasing the efficiency of the mechanical and air condition systems inside classrooms is important for appropriate ventilation and improving IAQ level.

Aims: This research was conducted to investigate the efficacy and feasibility of ozone-hydrogen peroxide advanced oxidation process as a post-treatment step of composting leachate treated by an anaerobic migrating blanket reactor biological treatment system. Materials and Methods: Leachate samples was collected from the effluent of the biological treatment system and used in an ozone reactor after dilution. The effectiveness of the pH values (4.5-11.5), H²O² concentrations (0.5-4 g/L), ozone doses (0.2-1 g/h) and reaction times (5-270 min) were evaluated to determine optimum operational conditions. Results: The highest removal efficiencies were achieved 72% and 79% for chemical oxygen demand (COD) and biochemical oxygen demand5 (BOD5), respectively, at pH 8.5, 2.5 g/L H ₂ O ₂ concentration, and 1 g/h ozone dose, during 270 min reaction time. Furthermore, results indicated that the BOD ₅ /COD ratio was decreased from 0.53 to 0.4 after 270 min reaction time. Conclusions: The O ₃ /H ₂ O ₂ was found to oxidize preferably COD and BOD ₅ of the leachate samples. In consequence, a decrease in the biodegradability of leachate was observed after oxidation treatment. The O ₃ /H ₂ O ₂ reaction proved to be a feasible technique for the oxidation of the leachate under study, and it can be considered a suitable treatment for this type of wastewater.

Aims: This study was conducted to determine the prevalence rate, virulence genes and antimicrobial resistance of Escherichia coli O157:H7/NM isolated from hamburger and chicken nugget in Isfahan, Iran. Material and Methods: From June 2013 to July 2013, a total of 190 hamburger (120) and chicken nugget (70), were collected from four randomly selected factories in Isfahan, Iran. They were evaluated for the presence of E. coli O157:H7/NM using microbiological culture and polymerase chain reaction. Statistical analysis was performed using SPSS software version 16.0 (SPSS Inc., Chicago o, IL, USA). Results: From a total of 190 samples analyzed four samples (2.1%) were contaminated with E. coli O157. All of the E. coli O157 were isolated from hamburger samples (3.3%) and chicken nugget samples were negative. Of four E. coli O157 isolated, only one sample was serotype E. coli O157:H7 and others were serotype E. coli O157:NM. Among four E. coli O157:H7/NM isolates, one strain was positive for all stx1, stx2, eaeA and ehxA genes. One strain was positive for stx2 gene. The other two were negative for these genes. All isolates (100%) were resistant to one or more antimicrobial agents. Conclusions: The results of this study showed that hamburger could be a significant source of E. coli O157:H7 and E. coli O157:NM serotypes in Iran and multi-resistance was found in 27% of E. coli O157 strains and this is a major public health concern.

Aims: The first aim of this study was to estimating the percentage of land area that was affected by various levels of light pollution and secondary aim is to assess the light pollution growth. Materials and Methods: This study describes a methodology for modeling light pollution in Bojnord city, using geographical information systems and remote sensing technology. The Defense Meteorological Satellite Program-Operational Linescan System (DMSP-OLS) and Landsat TM⁵ images in 1991, 1999, 2005 and 2012 were used. The DMSP-OLS images were classified to six categories from null to very high. The Landsat images were applied in order to calculate the urban area and extraction urban border in 4 years. Results: The results were showed that the light pollution area (km²) in very high category has increased 10.34, 2.73 and 15.94 km² of the entire study area from 1991-1998, 1998-2005 and 2005-2012, respectively. While, in that periods of time, the null category area (km²) declined 23.19, 21.97 and 100.36 km², respectively. In 2005 and 2012 about 92.8% and 86% of the total study area has been in the Null class. There was a direct association between urbanization, spatial development of urban areas and light pollution growth. Conclusions: One of the main reason for light pollution growth is declaring this region as capital city in 2005 and consequently, urban development and population emigration to capital.

Aims: The aims of this study was determination of driver behavior in car accident and analyzing the relationship between state anxieties (SA) with subscale of driving behavior. Materials and Methods: The self-reporting of the drivers was determined by using Manchester driving behavior questionnaire (DBQ) and Spielberger statetrait anxiety inventory in 168 drivers who had a crash while driving. Results: Independent t tests showed that violations (ordinary and aggressive) are the most common behavior in drivers, Pearson's correlation revealed that SA had a significant direct positive relationship with lapses (P < 0.01) and error subscales (P < 0.05), also Pearson's correlation showed that age had a negative significant relationship with factors of DBQ. Conclusion: It can be concluded from the results (according to the relationship between SA with error and lapses factor) that SA is destructive and affects the memory performance and mental process in the drivers and causes absent mindedness and imperfect memory function and process in these people during driving.

Aims: The purpose of this study was to investigate the composition of dental waste coming from six dental health services in Isfahan, Iran. Materials and Methods: From 45 public dental clinics in Isfahan, six public dental health services were selected (three dental clinics and three dental centers). Waste collection took place from October to December 2011. During this period, three samples were collected from each dental clinic and were divided to pre-determined groups manually. Results: In dental centers, the amount of infectious, non-infectious and domestic-type waste accounting for 45.07%, 12.15% and 42.78%, respectively. Whereas in dental clinics the production rates of infectious, non-infectious and domestic-type waste accounting for 52.2%, 8.58% and 39.22%, respectively. Conclusion: Overall, according to the results it can be said that integration of infectious and hazardous waste with general waste leads to the amount of infectious waste appears much greater than it actually is. The collection and disposal of amalgam and other hazardous dental solid waste should be regulated as soon as possible and to decrease the costs of dental waste management the uncontaminated recyclable items, which contained approximately 33% of total dental waste should be recycled or reused if possible.

Aims: In this research, modified Acroptilon repens (Russian knapweed) flower powder was used as a novel adsorbent for removal of Cr (VI) from synthetic wastewater. Materials and Methods: The batch adsorption studies were performed under various laboratory conditions with initial chromium concentrations of 2, 10 and 15 mg/l, adsorbent dose of 0.05-0.2 g/100 ml, contact time of 30-240, min and pH of 2-9. The solution was mixed with a mechanical shaker with 120 r.p.m. at 20°C. The suitability of the adsorbent was evaluated using Langmuir, Freundlich and Temkin isotherm models. For kinetic study, pseudo-first-order and pseudo-second-order kinetics were used. Results: The results indicated that maximum adsorption was achieved in acidic conditions. The optimum pH for the removal was 2. The capacity of chromium adsorption at equilibrium conditions increased by increasing the concentration of the adsorbate. The results also showed that the removal efficiency of Cr (VI) increased with increasing contact time. On increasing the initial concentration of the Cr (VI) solution, chromium removal reduced. The Freundlich and Langmuir isotherm models gave better accordance to the adsorption data in comparison with the Temkin equation. Adsorption of Cr (VI) followed pseudo-second-order kinetics rather than the pseudo-first-order kinetics. Conclusion: This study showed that modified Russian knapweed flower powder can be used as an effective lignocellulosic biomaterial and biosorbent for removal of Cr (VI) from wastewater.

Aims: The main goal of this study was to determine of the removal efficiency of chemical oxygen demand (COD) from educational hospital waste-water using electrocoagulation process by using iron and aluminum electrodes. Materials and Methods: A laboratory-scale batch reactor was conducted to determine the removal efficiency by the electrocoagulation method. Fifty-five samples of Shahid Mohammadi Hospital waste-water in Bandar Abbas were collected for the periods of 6 months according to standard methods. The removal of COD from the waste-water was determined at pH 3, 7, and 11 in the voltage range of 10, 20, and 30 V at the operation time of 30, 45, and 60 min. Data were analyzed in SPSS (version 16) using Pearson's correlation coefficient to analyze the relationship between these parameters. Results: The removal efficiency is increased by 6.2% with decreasing pH from 11 to 3 at the optimal condition of 30 V and 60 min operation time. By increasing the reaction time from 30 min to 60 min at voltages (10, 20, and 30 V), the removal efficiency was increased from 32.3% to 87.1%. The maximum COD removal efficiency was observed at pH 3 and voltage of 30 V and 60 min reaction time using four iron electrodes. Pearson correlation analysis showed a significant relationship between voltage and the reaction time with the removal efficiencies (P < 0.01). Conclusion: Due to the high efficiency of the electrocoagulation process and also the simplicity and relatively low-cost, it can be used for removing COD from hospital waste-water.

Aims: The purpose of the present study was to evaluate the effect of fabric stuff of work clothing that are widely used in Iran industries on the physiological strain index (PSI) at hot conditions in the climatic chamber. Materials and Methods: This interventional study was performed upon 18 male students in 16 trials, which included combination of four kinds of work clothing (13.7% viscose (VIS) 86.3% polyester(PES), 30.2% cotton [CT]-69.8% PES, 68.5% CT-31.5% PES, 100% CT, two activity levels (light and moderate) and two kinds of climatic conditions included hot-wet (T _a = 35, RH = 70%) and hot-dry (T _a = 38, RH = 40%). During each trial, the RH and core temperature was recorded once a minute and then PSI was calculated. Data were analyzed by using SPSS-16 software. Results: The results showed that in hot-wet conditions, the least value of PSI in light and moderate activities was related to 100% CT clothing and 30.2% CT-69.8% PES clothing, respectively. In hot-dry conditions, the least value of PSI in both of activities was related to 30.2% CT-69.8% PES clothing. The mean value of PSI in hot-wet conditions, during moderate activity had significant difference for various clothing types (P = 0.044). Conclusion: The research findings showed that for a heat strain reduction in hot-wet conditions at light activity level, 100% CT clothing is suitable. Furthermore, at moderate activity level, 30.2% CT-69.8% PES clothing and in hot-dry conditions, 30.2% CT-69.8% PES is suitable.

Aims: The present study was aimed to measurement of sound absorption coefficient of mineral wool and determination of their absorption ability. Materials and Methods: Mineral wool was used to find noise absorption coefficient. Random and normal sound absorption coefficient values were predicted. Then, the measures of transmission loss calculated as an overall value, for applied absorbent material and bare sheet metal. Results: The measured values of noise with one octave band frequency demonstrated an attenuation of 5.5-7 dB for these frequencies. The absorption coefficients of materials showed that mineral wool had more normal sound coefficients than its random sound absorption coefficient values. Conclusion: It can be concluded that predicted normal sound absorption coefficients of used mineral wool materials were near to the areas of standard line. It seems that the amount or thickness of absorbent lining was a main reason of noise reduction in low band frequencies. Mineral wool has a higher density and can provide better acoustical and insulating results than fiberglass. Besides, mineral wool doesn't lose its insulating value when wet and has an outstanding resistance to fire.

Aims: In this study, the effect of the coagulation process on treatment of simulated dairy wastewater (SDW) was investigated using the mineral and organic coagulants. Materials and Methods: Different types of coagulants such as inorganic (Alum and ferrous sulphate) and polymeric coagulants (polyacrylamide [PAA] and polyferric sulphate [PFS]) were investigated. Inorganic coagulants dosages were varied from 100 to 1000 mg/L and the polymers dosage was 20 mg/L. Turbidity, chemical oxygen demand (COD), electrical conductivity (EC) and chloride of samples were investigated in optimum pH. Results: Both two coagulants had an optimum dose and pH of 1000 mg/L and 5 respectively. According to the findings, Alum with 95% turbidity removal and 68% COD removal had more high efficiency than ferrous sulphate (95% and 62% efficiency for turbidity and COD removal respectively). When Alum via PFS and PAA as a coagulants aid were used, 82% decrease in COD was obtained using low dose of Alum (100 mg/L). Conclusion: In studied dairy wastewater, Alum was more effective than ferrous sulphate. Addition of 20 mg/L of both two coagulants aid (PFS and PAA) effectively reduced the use of Alum and it was effective in COD removal.

Aims: The aim of our study was to analyze the knowledge attitude and practice (KAP) of biomedical waste management among medical, paramedical students and health care professionals in Coimbatore Medical College Hospital in South India. Materials and Methods: Study was conducted among 400 health care professionals including doctors, nurses, nursing students, and laboratory technician course students. The results were evaluated. Results: It was found that the doctors had the maximum knowledge and practice among health care professionals. The results also indicate that knowledge is not uniform among individual group, and there exists considerable variation within the group. Conclusion: The results of our study revealed that the project for upgrading safety in health care initiative taken by the Government of Tamil Nadu to create awareness of biomedical waste management among health-care professionals have certainly improved the KAP on biomedical waste management. Hence, such a program is mandatory to improve the biomedical waste management in health-care centers.

Aims: The present investigation was carried out to study modulator effect of caffeine (1,3,7-Trimethylxanthine) on Arsenic-induced alterations on freshwater bivalve, Lamellidens corrianus. Materials and Methods: Freshwater Pelecypod Mollusc, L. corrianus were exposed to acute dose of arsenic (0.672 ppm As ³⁺ ) for 4 days. Arsenic exposed Bivalves were allowed to cure naturally and with caffeine. Testis and digestive glands from different groups were removed and dried in the oven. The dry powders were digested in nitric acid and perchloric acid in 4:1 ratio at hot temperature till dryness. The digest was dissolved in double glass distilled water and the arsenic contents were estimated by the Atomic Absorption Spectrophotometer. Results: After 4 days of exposure, the amount of bioaccumulated arsenic in the testis and digestive glands was 1.044 and 1.119 μg/g. During the recovery after 4 days, the bioaccumulated arsenic was reduced to 0.969 and 1.067 μg/g of normal water while in caffeine exposed Bivalves was reduced to 0.917 and 0.975 μg/g in testis and digestive glands respectively. Conclusion: Rapid reduction in the arsenic contents in caffeine exposed Bivalves indicates the role of caffeine in arsenic excretion. Therefore, the caffeine (1,3,7-Trimethylxanthine) as a modulator of Arsenic bioaccumulation in the experimental Pelecypod model, L. corrianus

Aims: The aim of the present study was to investigate the optimization of the treatment process of Bushigan water treatment plant (South of Iran) in respect of turbidity and total organic carbon (TOC) removal. Materials and Methods: The water samples were collected from Shapoor river the influent water to Bushigan treatment plant. A conventional jar test apparatus was used to evaluate the coagulation process. Different dosages of poly aluminum chloride (PACl), powdered activated carbon (PAC) and chlorine (Cl ₂ ) alone and with each other was used to determine their effects on removal of the turbidity and TOC. Results: The average of TOC and turbidity in raw water were 5.81 mg/L and 29 NTU respectively in all seasons. The study result showed that the removal efficiency of TOC and turbidity were improved with increasing the PACl and PAC dose. With the application of 12 mg/L PACl alone, the maximum TOC and turbidity removal efficiencies were 41% and 31%, respectively. At constant PACl dose, application of PAC as coagulant aid and adsorbent improved the removal efficiency of TOC and turbidity. Conclusion: The results were showed that by common water treatment method (coagulation and precipitation) using PACl as a coagulant and also PAC and Cl ₂ as an adsorbent and coagulant aid, the TOC and turbidity of water reduced to below 1 mg/L. So PAC and Cl ₂ can improve the coagulation process. This method can be used for water treatment plant with drinking water contain the average TOC less than 6 mg/L.

Aims: In this study, the effectiveness of chitosan as a coagulant aid in the removal of turbidity from surface water was investigated. Materials and Methods: A conventional jar test apparatus was used to evaluate the coagulation process. Coagulation of turbidity in river water using chitosan as coagulant aid and ferric chloride as coagulant was studied in the pH range 4-9 and initial turbidity concentrations in the range of 20-200 mg/l. Results: The findings showed that the optimum pH for FeCl ₃ as a coagulant on turbidity removal was seven. About 95% removal of turbidity is achieved at this pH, without filtration and the residual turbidity drops below 5 NTU. The optimum dosage of FeCl ₃ was achieved 10 mg/l. The optimal chitosan concentration required to effect coagulation is 0.5 mg/l. Restabilization of the turbidity is observed at higher concentrations of chitosan. When chitosan (0.5 mg/l) used as a coagulant aid, efficiency removal turbidity was increased and optimal dosage of FeCl ₃ turbidity removal was reduced to 50% of initial dosage of FeCl ₃ . Conclusion: Chitosan as natural coagulant aid improved turbidity removal efficiency by coagulation process. And FeCl ₃ concentration as coagulant was reduced then residual iron decreased in treated water. Also by using natural coagulant considerable savings in chemicals and sludge handling cost may be achieved.

Aims: In the present study, activated carbon obtained from pistachio hull waste ash was used as an adsorbent for the successful removal of reactive red 198 dye from aqueous solutions. Materials and Methods: The effect of various operating parameters such as initial concentration of dye (20-200 mg/L), contact time (5-270 min), adsorbent dosage (0.1-5 g/L) and pH (2-12) was investigated. Furthermore, equilibrium isotherms were used to identify the possible mechanism of the adsorption process. Results: Maximum adsorption capacity of the adsorbent was 253.67 mg/g at pH 2, initial concentration of 80 mg/L and 25°C, when 95.13% of the dye was removed. Furthermore, the equilibrium data were also fitted to the Langmuir and Freundlich equilibrium isotherm models. It was found that the data fitted to Freundlich (R² = 0.9289) better than Langmuir (R² = 0.8839) model. Conclusion: It was concluded that the activated carbon obtained from pistachio hull waste ash can be used for dyes removal from water and wastewater.

Aims: This study focused on the determination of various physico-chemical characteristics of groundwater and to perform a statistical analysis to determine the relationship between the measured parameters. Materials and Methods: The study was carried out during April-May 2011, in Vellore city, India. The various physico-chemical characteristics such as pH, turbidity, chlorides, acidity, alkalinity, sulphates, dissolved oxygen, and hardness were determined by following the procedure prescribed by American Public Health Association standard methods. This study was carried out to ensure the quality of groundwater to make use of it for domestic purpose by comparing the analytical results with the Bureau of Indian Standards (BIS) and World Health Organization (WHO) drinking water quality standards. A statistical study such as correlation analysis and one-way analysis of variance (ANOVA) has been carried out using Statistical Package for the Social Science (SPSS) ver. 20 software. The correlation analysis was performed for measured parameters to determine the relationship between the variables. The One-way ANOVA was applied to estimate the uncertainty in measured values. Results: All the measured parameters are within the permissible limit as per WHO and BIS. The statistical analysis for all the parameters has revealed a positive correlation and the F test values are significant at 95% level. Conclusion: From the investigation results, it can be concluded that the water quality of the study area is fit for domestic purposes. The descriptive statistics of the parameters analyzed along with correlation matrix and one-way analysis proved that there is no variation among the measured parameters.

Aims: The aim of this study was to determine and evaluate the potential methods for restoration of waste processing and recycling units in the Khazra Industrial region in Kerman, Iran. Materials and Methods: The present research was a field study performed by organizing a questionnaire and implementing local surveys during 1 year. At first, detailed information of the status of the industrial waste production including its amount, composition, percent of components and percent of waste generated by each industrial zone was identified. Then the industrial sites present in each zone were classified in different groups. Furthermore, the various wastes produced in these industries were analyzed according to type, nature, recyclability, place of production, production frequency and quantity of waste. Results: In the Khazra Industrial Park 97 industrial units are operating, with the approximate production capacity of 729670.5 tons different products a year, which make 26141 tons waste annually. Totally 41 types of waste are produced in Khazra Industrial Park, of which 9 types can be recycled. Conclusion: Overall, our findings suggest that the total amount and the variety of waste generated, and the availability of waste-recycling units in the park hinder the establishment of any recycling and processing units in the Khazra Industrial Park as they are not economically efficient. Therefore if the park development plans get going and by using economic initiatives, the foundation of processing and recycling units in this industrial park is recommended and will have economic and environmental benefits.

Aims: The objective of the present study was to evaluate the performance of an aerobic fixed-bed bioreactor (FBR) enriched with microorganisms of sewage sludge in biodegradation of formaldehyde in air stream with various retention times and airflow rates in laboratory scale. Materials and Methods: An aerobic biofilter 60 cm in height and 14 cm internal diameter made of steel was constructed and packed with a mixture of pumice and compost as a medium and utilized in this study. The microorganism's growth, which is derived from the sludge of a municipal wastewater treatment plant, was initiated by adding nutrient. During the first few days of run, the airflow containing different concentrations of formaldehyde (from 24 ± 3 to 224 ± 5 mg/m ³ ) was introduced to the reactor to ensure biological adaptation. Sampling was performed through a series of two impingers containing adsorbent, and analyzed by chromotropic acid assay using DR-5000. Results: The maximum removal and elimination capacity of formaldehyde was yielded at 0.48 ± 0.06 g/m ³ /h inlet loading rate and 180 s of empty bed retention time (EBRT). These values for stabilized days were almost 88% and 0.42 g/m ³ /h, respectively. Conclusion: The results showed that by increasing the inlet concentration of formaldehyde and reducing the EBRT, the formaldehyde removal capacity of the system decreases. Aerobic bioreactor with appropriate bed volume and compatible with inlet pollutant mass flow rate in optimum retention time will admissibly degrade and reduce the formaldehyde concentration from contaminated gas phase, such as gases produced in municipal wastewater treatment facilities.

Aims: The aim of present study was macro-ergonomic risk assessment with a relative stress index (RSI) in textile industry. Materials and Methods: This study was conducted based on the Census method among 154 workers in textile industry in Isfahan (IRI) that work on three shifts. Risk assessment based on RSI is divided into three main sections: job description, check list, and RSI. For computation of this method, different equations have been defended that by their computation was being performed. The final values for the RSI area scale between zero and 10 where zero implies on dangerous, insecure, not efficient and number 10 indicated safe, secure, and being efficient. Results: ANOVA test showed that, hand work and sensory in different shifts among textile industry had significant relationships with occupational hazard (P < 0.05). Also, posture with a mean 6.19 ± 0.11 and manual material handling with a mean 9.14 ± 0.41 had the lowest and highest score, respectively. Conclusion: Based on the findings from the study, the posture at work and hand work were the most influential factor to the incidence of occupational hazards among workers with in the textile industry. So keeping a good posture and reducing the level of hand work activity during each shift can have a significant impact in reducing occupational hazards.

Aims: This research was conducted to evaluate the Arsenic (As), Lead (Pb), and Cadmium (Cd) concentrations in fish flesh samples of Bara'an (east of Isfahan) as a contaminated zone. In addition, the obtained result was compared with a control fish group from behind dam area (west of Isfahan). Material and Methods: In this cross sectional study, 21 fish samples were collected from both the areas and heavy metals concentration was measured by flame Atomic absorption spectrometric method (PERKIN Elmer model 2380). Results: The mean amount of As were 2.97 ± 1.51 and 2.87 ± 0.3 mg/kg in the behind dam and the Bara'an areas, respectively. The mean amount of Pb were 0.66 ± 0.37 and 0.32 ± 0.17 mg/kg in the behind dam and the Bara'an areas, respectively. The mean concentration of Cd were 3.7 ± 4.11 and 86.64 ± 32.4 mg/kg in the behind dam and the Bara'an areas, respectively. The t-test showed no significant differences between the mean concentrations of As in both groups (2.97 Vs 2.87) (P = 0.78). The mean concentrations of Pb in the Bara'an area was significantly less than the behind dam area (0.32 Vs 0.66) (P < 0.001). Instead the mean concentration of Cd in the Bara'an area was significantly more than behind dam area (86.64 Vs 3.7) (P < 0.001). Conclusion: This study confirmed that the fish samples from Zayanderoud at Bara'an and behind dam was contaminated by As, Pb, and Cd. Therefore, we suggest that the heavy metal levels should be monitored regularly.

Aims: This study was conducted to determine the state of physical symptoms of the Iranian Central Iron Ore Company workers and its relation with history of work accidents. Materials and Methods: This cross-sectional descriptive study was performed at the Iranian Central Iron Ore Company and included 388 workers sampled randomly out of 2100 workers. Research tool was a two-part questionnaire that its reliability was determined by some of researchers. Data was analyzed by SPSS (Statistical Package for Social Science) software and statistical tests included variance analysis and Pearson' correlation tests. Results: According to the findings, 80.9% had favorable physical health conditions and there was a significant relationship between physical health condition, history of work accidents, cigarette smoking and type of work. Conclusion: Considering the strong relationship between physical health and history of work accidents, it is proposed that high-level managers of the Central Iron Ore Company of Iran should pay special attention to the improvement of physical health, psychological, social, and welfare levels.

Aims: The objective of this study was to evaluate the prevalence of Listeria spp. in the river water before and after discharge of the effluent of the municipal wastewater treatment plant (WWTP) in Isfahan, Iran. Materials and Methods: A total of 66 samples were collected bi-weekly over 4 months from eleven discrete sampling locations in Zayandehrood River, Iran. Three sampling sites were located above the discharge point and five sites were located after the discharge point of WWTP. Samples were also collected from the influent and the effluent of WWTP. Listeria spp. were isolated using a selective enrichment procedure and a subculture onto polymyxin-acriflavine-lithium chloride-ceftazidime-esculin-mannitol Agar. All isolates were subjected to standard biochemical tests. Results: L. monocytogenes was isolated from influent (83%), effluent (50%) and (18.5%) river water. Listeria spp. was not found before the discharge point in river water. However, L. monocytogenes was isolated in samples collected from 200 m (33%), 500 m (33%), 2 km (16.5%), 5 km (16.5%) and 10 km (16.5%) downstream from the WWTP. Listeria innocua (9%) and Listeria seeligeri (10%) were the second most frequently isolated species. Conclusion: During the wastewater treatment, Listeria spp. is not removed completely. L. monocytogenes is widely distributed in the Zayandehrood river. L. monocytogenes released into surface water demonstrates a potential risk for public health. These results indicate the need for appropriate water management in order to reduce human and animal exposure to such pathogens.

Aims: The objective of this study was to analyze major accidents take place in sour water refineries, and to assess the adequacy of safeguard layers in the system. Also it has been provided safety recommendations in regarding to our analysis. Materials and Methods: Using the layer of protection analysis (LOPA), the role of protective layers in controlling the potential risks in Sour Water Recycling Unit is determined and required recommendations to reduce risk are provided. Results: This study showed that there are 49 high risk areas in Sour Water Recycling Unit. Moreover, Excessive flow rate in pipelines, Excessive temperature, Reverse flow, H ₂ S leakage, Flow interruption, and Corrosion are the main identified hazards. Conclusion: It can be conclude that the effectiveness of protective layers is not enough and additional protective layers are required to improve the process safety system. Furthermore, LOPA is an improved technique when use the output of hazard and operability study (HAZOP) and it has some advantages due to its semi-quantitative nature in estimating hazards.

Aims: The purpose of this study was to isolate and identify aerobic polychlorinated biphenyls (PCBs) degrading bacteria. Materials and Methods: This study was performed in lab scale aerobic sequencing batch biofilm reactor. Polyurethane foams were used as bio-carrier and synthetic wastewater was prepared with PCBs in transformer oil as the main substrate (20-700 μg/l) and acetone as a solvent for PCBs as well as microelements. After achieving to adequate microbial population and acclimation of microorganisms to PCB compounds with high efficiency of PCB removal, identification of degrading microbial species was performed by 16s rRNA gene sequencing of isolated bacteria. Results: Gene sequencing results of the isolated bacteria showed that Rhodococcus spp., Pseudomonas spp., Pseudoxanthomonas spp., Agromyces spp., and Brevibacillus spp. were dominant PCB-degrading bacteria. Conclusion: PCB compounds can be degraded by some microorganisms under aerobic or anaerobic conditions or at least be reduced to low chlorinated congeners, despite their chemical stability and toxicity. Based on the results of the study, five bacterial species capable of degrading PCBs in transformer oil have been identified.

Aims: This study was carried out to determine nitrite and nitrate levels in fresh leek and spinach from different greengrocers' shops of Urmia (Iran) and then the effect of boiling and the effect of aqueous boiling pH were studied. Materials and Methods: Nitrite and nitrate content of 15 market samples of leek and spinach from Urmia region were determined by spectrophotometric method. Effect of boiling and their pH levels at home processing condition were studied. Results: Results showed that the fresh vegetables had only traces of nitrite and the level of nitrate was 36-328 ppm KNO ₃ . In the most of samples, nitrite and nitrate contents in spinach were greater than in leek, but lower than standard International Organization for Standardization levels in Iran. Boiling process was carried out, according to home conditions and it caused a decrease in nitrate levels between 23% and 61% in leak and spinach samples, respectively. T-test analysis of the boiled vegetables showed a significant reduction about 75% in nitrate content (in dry weight vegetable content), in the samples, but an increase in nitrate content in the boiled water of the sample was observed. The effect pH of boiling (4-8) shows that with an increase in pH, there was a decrease in nitrate contents of boiled water. Conclusion: The experiment showed that the leek and spinach marketed in Urmia region were safe for consumption and boiling of vegetables caused the release of nitrates from vegetables to water after the cooking process. It is of particular importance not to use the vegetable cooking water for use in pureeing homemade baby foods.

Aims: This study aimed to monitor the vibration levels of mining machinery and duration of exposure to vibration; to study work practices of operators of mining machineries and to predict health risk from vibration exposure to operators. Materials and Methods: Vibration levels of 157 mining equipment including dumpers, dozers, etc. in 10 opencast mines were measured through accelerometer and recorded in vibration analyzer. Root mean square (RMS) values of acceleration as well as vibration dose values along with duration of exposures per day were used to predict health risk in accordance with ISO 2631-1:1997 standard. Video records of equipment operation were used to analyze job components. Results: Health risk was evaluated using RMS acceleration (0.21-1.82 m/s ² ) and corresponding daily durations of exposure (2-7.5 h). Forty two (27%) of the equipment showed minimal health risk, 83 (53%) equipment showed moderate and 32 (20%) equipment showed high health risk to operators. While shovels and excavators showed minimal health risk, dozers and dumpers showed high health risk potential. x-axis was the dominant axis of vibration for loaders and dozers, whereas for the majority of dumpers and tippers, z-axis was dominant. Conclusion: Dumpers require engineering control for reducing the vibration in z-axis while measures are required for x-axis in loaders or dozers. Shovels or excavators do not require immediate attention except regular monitoring. Improvement in work practices are required to safeguard the workers from vibration related illness. It is recommended that proper guidelines for measurement and control of vibration at workplace should be formulated.

Aims: The aim of this study was to assess the effect of shift work on metabolic syndrome in Iran Polyacryl Corporation workers. Materials and Methods: This retrospective cohort study was conducted on Iran Polyacryl Corporation workers for 10 years. The incidence of metabolic syndrome was assessed between shift workers and day workers. For analysis of the effects of shift work on six different combinations of metabolic syndrome, Logistic regression was used, and information was analyzed with using Statistical Package for Social Science-SPSS version 18. Results: The mean triglyceride, body mass index, total cholesterol, and systolic blood pressure was higher in the day workers than rotating shift workers, but the difference was not significant (P value > 0.05). Logistic regression showed a significant inverse relationship between shift work and combination of three metabolic syndromes with a relative risk (RR) and %95 confidence interval (CI) of 0.24 and (0.06-0.94), respectively. Although shifts work increased risk of combination of numbers 2 (IFG, BP, and BMI) and 4 (IFG,TG, and BMI) metabolic syndrome 66% and 6%. These differences were not significant (RR = 1.66, %95 CI ; 0.81-3.37 and RR = 1.06, %95 CI ; 0.72-1.58 respectively). Other combinations of metabolic syndrome had a non-significant inverse relationship with shift work (P value > 0.05). Conclusion: Our findings indicate that rotating shift work not increases the risk of metabolic syndrome and different combinations. However, significantly decreased risk for developing combination 3 (Impaired fasting glucose, hypertension, and positive micro albuminuria).

Aims: This study aimed to evaluate the concentrations of toluene and ethylbenzene inside the Pride cars and to investigate the effects of the vehicle ventilation system, fule type, and interior smoking on their concentration. Materials and Methods: In the present study, 152 different models of Pride cars, stopped in parking [classified into three groups including: Pride KIA (Group I), Saba (Group II) 131, 141, 132, LX111, SX, and Nasim (Group III)] were sampled using activated carbon sorbent tube. The samples were analyzed using gas chromatograph-mass spectrometer. The vehicle ventilation, fuel type, and in-cabin smoking were recorded. Results: The average concentrations of toluene and ethylbenzene were 105.4 ± 270.5 and 19.09 ± 33.97 μg/m ³ , respectively. The average concentration of toluene was higher than that of ethylbenzene. The concentration differences of both toluene and ethylbenzen among the studied groups were not statistically significant. Conclusion: The ventilation condition, fuel type, and in-cabin smoking were not significantly impressive on the toluene and ethylbenzene concentrations inside the cars. However, simultaneous usage of the vehicle ventilation system and natural ventilation (windows) could lead to little decrease in toluene concentration levels inside the car, while smoking consumption by passengers can increase them.

Aims: The present study aimed to assess the occupational health problems of municipal solid waste management workers. Material and Methods: Cross-sectional descriptive study was conducted among solid waste management workers of Kerala, India. All workers (408) were included the study of which 313 (77%) participated. Data were collected by direct interview and clinical examination using a structured questionnaire. The observed morbidity like respiratory diseases, eye diseases, dermatological problems and nail infections were elicited by clinical examination. The point prevalence of other occupational related health events present either during the study time or during 1 month recall period and that occurred ever after entry in present occupation was collected by self-reported complaints and doctors diagnoses. Results: The mean age was 42.5 ± 7.2 years. The observed morbidity like respiratory diseases, eye diseases, dermatological problems, nail infections were high ranged from 21% to 47%. The reported prevalence of occupation related morbidities like falls (63.6%), accidents (22%), injuries (73.2%), and water-vector borne disease (7.1%) were high. The current prevalence of musculoskeletal morbidities showing that all major joints are involved (17-39%). Conclusions: The work related health-problems were reported to be high. The prevalence of Respiratory, dermatological, eye problems and injury, musculoskeletal problems were reported to be high among municipal solid work handlers. Measures are needed to improve the work environment of waste handlers by ensuring availability protective gears based on ergonomic principles, clean drinking water and washing and sanitation facilities during working hours.

Aims: In this study, the prevalence of antibiotic residues in pasteurized and sterilized commercial milk available in Shahre-kourd, Iran, was investigated. In addition, the influence of seasonal temperature changes on the prevalence of contamination was studied. Materials and Methods: Commercial milk samples of 187, including 154 pasteurized and 33 sterilized, milk samples were collected from the market between early January 2012 and late July of the same year. The presence of antibiotic residues was detected using the microbiological detection test kit, Eclipse 100, as a semi-quantitative method. Results: The results showed that 37 of the samples (19.8%) have contained antibiotic residues above the European Union Maximum Residues Limits (EU-MRLs), of which 28 samples (14.97%) were found to be contaminated but at the concentrations below the EU-MRLs. There was no significant difference between the contamination rate of pasteurized and Ultra High Temperature (UHT)-sterilized samples. Similarly, variation of weather temperature with seasons had no effect on the contamination prevalence of milk samples ( P > 0.05). Conclusion: Based on the result of this study, antibiotics residues were present in the majority of milk samples. Neither the season nor the type of thermal processing of the commercial milks had noticeable impact on the prevalence level of the milk samples. However, an increasing trend of prevalence level for antibiotic residues was observed with increasing the temperature through the warm season.

Aims : The objective of this study was investigation of the polycyclic aromatic hydrocarbons (PAHs) concentration in eight brands of black tea which is used more in Iran. Materials and Methods : In the present study, PAHs content of eight brands of black tea were extracted and analyzed with gas chromatography-mass spectrometry (GC-MS) equipped with Selected Ion Monitoring (SIM) technique. Results: The average of total PAHs compounds in analyzed teas was in the range of 139 to 2082 μg kg ^?−1 . PAHs with 5 to 6 rings were not found in the teas samples. Four rings PAHs compounds composed 46% of the total PAHs compounds and were the most dominant compounds. The same compounds were also dominant in tea bags. Conclusion: In the tea liquor, after brewing times of 10 and 120 minutes, the maximum and minimum releasing percentage of PAHs was observed, respectively. The result of this study confirmed the presence of PAHs in the tea leaves and tea liquor. Assuming that every person use 10 g of tea leaves every day and 10 minutes take for brewing time, the daily uptake of 16 PAHs will be 1.2 μg.

Aims: In this work, degradation of 4-chlorophenol (4-CP) was investigated in aqueous solutions using several oxidation systems involving ultraviolet/(UV)/H ₂ O ₂ , microwave (MW)/H ₂ O ₂ , and ultrasonic (US)/Fenton systems. Materials and Methods: Three pilot plant reactors consist of a photolytic reactor, a modified domestic MW, and an US bath reactor of 22 kHz frequency were constructed and separately used in batch mode. The effects of several operation parameters such as pH of the solution ranging 3-10, H ₂ O ₂ initial concentration ranging from 0.005 to 0.2 mol/l, and reaction time were examined. Concentration changes of 4-CP were determined using a spectrophotometer at an absorption wavelength of 500 nm. Results: The results show that the oxidation rate was influenced by many factors, such as the pH value, reaction times, and the amount of H ₂ O ₂ concentration. The optimum conditions obtained for the best degradation rate were pH = 7, H ₂ O ₂ concentration of about 0.05 mol/l and pH = 10, H ₂ O ₂ concentration of about 0.1 mol/l for UV/H ₂ O ₂ and MW/H ₂ O ₂ system, respectively. For US/Fenton system, the highest 4-CP degradation was achieved in pH = 3, H ₂ O ₂ concentration of about 0.05 mol/l in the percent of 0.025 mmol Fe/l. The highest 4-CP removal rate in optimum conditions of pH and concentration of H ₂ O ₂ , in UV/H ₂ O ₂ , MW/H ₂ O ₂ , and US/Fenton systems was >99% over the retention time of 40 min, 85% after 180 min, and >99% after 40 min, respectively. Conclusion: Based on the results of this study, the UV/H ₂ O ₂ and US/H ₂ O ₂ are successfully applicable for degradation of 4-CP in aqueous solution. Also, the kinetic study represented that the US/H ₂ O ₂ is capable of removing 4-CP slightly rather than UV/H ₂ O ₂ process.

Aims: This study investigated the annual and seasonal variation of turbidity; total dissolved solid (TDS), nitrate and nitrite in Parsabad water treatment plant (WTP), Iran. Materials and Methods: The water samples were obtained from the inlet and outlet of Parsabad WTP from February 2002 to June 2009. The samples' turbidity, TDS, nitrate, nitrite, pH, and temperature were measured according to standard methods once a month and the average of these parameters were calculated for each season of year. Results: The maximum concentration of inlet turbidity, TDS, nitrate and nitrite were 691, 700.5, 25, and 0.17 mg/l, respectively. These parameters for outlet samples in the study period were 3.0, 696.7, 18, and 0.06 mg/l, respectively. While these concentrations in outlet zone were lower than World Health Organization (WHO) or United States Environmental Protection Agency (US-EPA) water quality guidelines, WTP could not reduce the TDS, nitrate, nitrite and pH value and these parameters were not different in the inlet and outlet samples. However, the WTP reduced the turbidity significantly with an efficiency of up to 85%. Conclusion: This study showed that a common WTP with rapid sand filtration can treat a maximum river turbidity of 700 NTU in several years. As no differences were observed between inlet and outlet TDS, nitrate, nitrite and pH in the studied WTP. It can be concluded that compensatory schemes should be predicted for modification of these parameters when they exceed the standards in the emergency situations.

Aims: This study aimed to determine the concentration of heavy metals including lead (Pb), cadmium (Cd), and arsenic (As) in rice samples in Yazd markets. Materials and Methods: In this study, 108 rice samples were collected from 36 different brands including 26 imported and 10 Iranian rice varieties from July-December 2011. Determination of heavy metals was carried out by wet ashing and digestion methods following graphite furnace atomic absorption spectrometry and hydride generation atomic absorption spectrometry. Results: The average concentrations of lead in both Iranian and imported samples were 328.3 ± 81.44 and 254.55 ± 77.2 μg/kg, respectively, well above the safe limit set by Iranian standard, whereas mean concentrations of cadmium and arsenic were both below their permissible limit. In homemade rice samples, their concentration levels were shown to be 37.25 ± 23.39 and 33.5 ± 18.35 μg/kg, respectively. However, for imported products, their levels were 43.71 ± 13.74 and 87.55 ± 72.99 μg/kg, respectively. Conclusion: Deterministic estimation of exposure to heavy metals from rice showed that there was no health issue concerning exposure to toxic metals through rice intake in Iran when potential risk of each heavy metal is considered individually, cumulative risk assessment must be applied in future studies.

Aims: The aim of this study was to identify the sources of airborne contaminants in milk processing units. Materials and Methods: The aero-bacteriological investigation has been done fortnightly for a period of 1 year extramurally within the premises of milk processing unit complex with the help of modified two-stage Andersen Sampler. The raw milk samples were analyzed for total plate count and total coliform count. Results: The mean ± standard deviation of bioload of total coliform/mL, total plate count in million/mL, total airborne viable cultivable bacteria, Gram-negative bacteria, and the members of the family Enterobacteriaceae recorded were 3193.6 ± 220, 1673.33 ± 229.8, 3117.96 ± 1678.1, 46.33 ± 28.874, and 47.92 ± 33.5, respectively. Seasonal variations in airborne bacterial population were reported for this environment, high humidity and moderate temperature were the major factors for dissemination and distribution of Gram-negative bacilli. The temperature was positively and humidity was negatively significantly correlated with total airborne viable cultivable bacteria of this environment. There was no correlation established between bioload of milk and bioload of airborne bacteria. Conclusion: The airborne bacterial bioload in milk processing unit complex environment areas were higher than the acceptable limit, with temporal and spatial variations. Mechanical activities were supposed to be the key factor governing aerosolization of potentially harmful bacteria which could contaminate the products. These results could be useful to establish a standard to the small-scale dairy processing units where monitoring of airborne bacteria were rarely adopted by dairy manufacturers in their routine quality control.

Aims: The purpose of this study was to investigate the professional attraction rates on solid waste recovery area, current recovery market in the study area, and to determine their activity index. Materials and Methods: The recovery of materials in the active industrial units of Isfahan industrial parks, central area of Iran, were classified and analyzed. The quantitative and experimental studies were used. In each recovery area, employment, investment rate, and production capacity of industrial units were specified and the activity index was prescribed. Results: The highest activity index in the province relates to paper and metal with 17 and 16 units, respectively. In the study area, no study has been carried out about electronic waste and old cars recovery. Also employment in paper and metal recovery industrials are more than another with 385 and 221 persons per year, respectively. Conclusion: The recovery of solid waste and distribution of solid waste production in Isfahan showed that planning of solid waste recovery industry can be developed in future.

Aims: The objective of present study was to evaluate the new location of Isfahan solid waste sanitary landfill using Geographical Information System (GIS) based on the Oleckno index method (OIM). Materials and Methods: This study was on the field- and library-based data collection and surveys of relevant data. Assessment parameters included average annual rainfall, soil type and ground water beneath and adjucent to the landfill site. To analyze data, ArcGIS version 9.3 was used. Results: In 2010 the total rainfall in the landfill location was less than 150 mm/year. The soil type was clay loam, and the average distance from the floor of the landfill to the groundwater level was 3-9 meters. As calculated results showed that, the Oleckno index (OI) score in the study area was 40. Conclusion: The new Isfahan's sanitary solid waste landfill site had a good OI and the possibility of contamination of groundwater by leachate production based on this method also was low.

Aims: The aim of this study was to investigate the relationship between longitudinal change in total cholesterol as a main cardiovascular disease risk factor and shift work, controlling for the effect of the weight at baseline of recruitment. Materials and Methods: This retrospective cohort study consists of 674 employees of Iranian Corporation Polyacril from 1992 to 2009. Stratified analysis of the relationship between shift work and cholesterol based on weight status at baseline of recruitment controlled for the effect of confounders including age, body mass index, pre-employment cholesterol, glucose, triglyceride, urea, work types, education, and marital status. A linear mixed model used for analyzing the data. Estimation of parameters has done by Bayesian approaches using Winbugs statistical software. Bayesian confidence interval (CI) was used for testing regression coefficients. Results: Average age mean at employment was 25 years (standard deviation [SD] =3.3); the average number of measurement for each individual was 3.7 times (SD = 0.6). In this model, relationship between shift work and cholesterol changes controlled for confounding factors was significant in whom overweight was at baseline (beta = 2.25, P < 0.001, 95% CI: 0.67-3.88) but was not significant for whom overweight was at baseline of employment. Conclusions : The rate of cholesterol changes was higher for normal weight shift workers compared with workers who were overweight at baseline of recruitment.

Aims: The purpose of this study was to investigate the efficiency of manganese oxide-coated sand in the presence of magnetic field to treat urban runoff. Materials and Methods: A flow-through column having a diameter of 50 mm was filled with coated sand and used to conduct the experiments in this study. Atomic absorption, turbidimeter, pH meter, and spectrophotometer DR5000 were used to measure heavy metals, turbidity, pH, phosphate, and nitrate, respectively. The surface of coated sand was assessed by SEM. Energy dispersive X-ray analysis (EDAX) analysis was used to determine percentage of sand components. Results: SEM and EDAX analyses confirmed that the sand has been coated with manganese oxide successfully. Results indicated that turbidity, Pb, Zn, and PO ₄ removal efficiency by the coated sand in the presence of magnetic field were 89.6%, 65.9%, 81.1% and 67%, respectively. The results indicated that the coated sand is not able to remove NO ₃ . Conclusion: Manganese oxide-coated sand filter in the presence of magnetic field improve the quality of urban runoff significantly. Authors believe that this approach is simple, economical and efficient as in comparison to other existing methods. This could be a promising treatment technology that can enhance quality of urban runoff and industrial wastewaters.

Aims: Traditionally, roadway safety analyses have used univariate distributions to model crash data for each level of severity separately. This paper uses the multivariate Poisson lognormal (MVPLN) models to estimate the expected crash frequency by two levels of severity and then compares those estimates with the univariate Poisson-lognormal (UVPLN) and the univariate Poisson (UVP) models. Materials and Methods: The parameters estimation is done by Bayesian method for crash data at two levels of severity at the intersection of Isfahan city for 6 months. Results: The results showed that there was over-dispersion issue in data. The UVP model is not able to overcome this problem while the MVPLN model can account for over-dispersion. Also, the estimates of the extra Poisson variation parameters in the MVPLN model were smaller than the UVPLN model that causes improvement in the precision of the MNPLN model. Hence, the MVPLN model is better fitted to the data set. Also, results showed effect of the total Average annual daily traffic (AADT) on the property damage only crash was significant in the all of models but effect of the total left turn AADT on the injuries and fatalities crash was significant just in the UVP model. Hence, holding all other factors fixed more property damage only crashes were expected on more the total AADT. For example, under MVPLN model an increase of 1000 vehicles in (average) the total AADT was predicted to result in 31% more property damage only crash. Conclusion: Hence, reduction of total AADT was predicted to be highly cost-effective, in terms of the crash cost reductions over the long run.

Aims: This study was conducted to determine Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) concentration regarding broken petroleum transmission pipeline in the east region of Isfahan, using passive sampling method. Materials and Methods: Dialysis bags as passive sampling devices with molecular cut-off diameter of 12000 Dalton, 3.2 cm width and around 12 cm lengths were used that contain 2 ml of olive oil as an absorbent. These devices were placed, in 10 sampling wells for 45 days. In order to determine the absorption efficiency of these devices, laboratory calibration operations were performed at the same time. Nitrate as an indicator of contamination of groundwater with chemical fertilizers and also electrical conductivity (EC) as an indicator for cations and anions concentration was measured. Results: The laboratory absorption efficiencies of BTEX were found to be 90%, 85%, 79%, and 81%, respectively. Concentration of these compounds in field samples were less than 10 μg/l. Nitrate concentration varied between 2.1 to 69.2 mg/l, and EC varied between 1.7 to 15.1 mS/cm. Conclusion: BTEX compounds were absorbed with high efficiency in the laboratory test, but their concentrations in wells were found to be negligible. Average concentration of nitrate in the wells was less than water quality guidelines, and had no relation with the direction of movement or depth of water. EC tended to increase in the direction of groundwater movement, but there were no correlations among depth of water, nitrate concentration, and mean of EC.

Aims: The aim of this study was to determine the peroxide value, acid value and rancidity of edible oil which are used in sweet pancake, samosa, confectionery and sandwich shop. Materials and Methods: This descriptive study was carried out on all sandwich shops and sweet pancake at north region of Isfahan city. The peroxide value, acid value and rancidity were determined based on national standard procedure number 4179, on thirty samples. Results: The average of peroxide and acid value was 5.2 and 0.5, respectively. Around 7.4 percent of tested oil has a non permissible rancidity value. Also, 87 percent of samples were healthy. In general, 98.1 percent of oil samples were unusable. Conclusion: The acid and peroxide numbers was in acceptable range, however, the rancidity or oil chemicals corruption caused by inappropriate conservation conditions. This type of fast food, have adverse effects on consumers' health.

Aims: The aim of present study was determination of occurrence of Listeria Listeria spp. in various point of a municipal wastewater treatment plant. Materials and Methods: The samples were collected of influent, effluent, raw sludge, stabilized sludge and dried sludge from north wastewater treatment plant Isfahan, Iran. The presence of Listeria spp. was determined using USDA procedure and enumerated by a three-tube most probable number assay using Fraser enrichment broth. Then, biochemically identified Listeria monocytogenes was further confirmed by PCR amplification. Results: L. monocytogenes, L. innocua and L. seeligeri were isolated from 76.9%, 23.1% and 23.1% of influent, 38.5%, 46.2% and 7.7% of effluent, 84.6%, 69.2% and 46.2% of raw sludge, 69.2%, 76.9% and 0% of stabilized sludge and 46.2%, 7.7% and 0% of dried sludge samples, respectively. The efficiency of wastewater treatment processes, digester tank and drying bed in removal of L. monocytogenes were 69.6%, 64.7% and 73.4%, respectively. All phenotypically identified L. monocytogenes were further confirmed by PCR method. Conclusion: Application of sewage sludge in agricultural farms as fertilizer may result in bacteria spreading in agriculture fields and contaminated foods with plant origin. This may cause a risk of spreading disease to human and animals. Using parameters such as BOD ₅ is not sufficient standard for the elimination of pathogenic microorganisms.