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: The main objectives of this study were evaluation of the efficiencies of bioventing (BV), soil vapor extraction (SVE) and transition regime between BV and SVE (air injection bioventing [AIBV]) for benzene and toluene removal from polluted sandy soils. Materials and Methods: Laboratory-scale set-up consisted of three cylindrical units (with 29 cm in length with a 7.29 cm i.d.) was conducted to study the removal efficiency of three in-situ remediation technologies. Results: The results showed that, after 48-h air injection with constant air flow rate of 250 mL/min, benzene (initial concentration of 1 mg/g of soil) removal efficiency in BV, SVE and AIBV reactors were almost 84, 98 and >99.5%, respectively. Also results indicated that, toluene with a similar concentration was successfully (>99.5%) reduced via AIBV technology, after 72-h continuous air injection. Conclusion: Comparison of the BV, SVE and AIBV technologies indicated that all of those technologies are efficient for remediation of unsaturated zone, but after specific remediation time frames, only AIBV able to support guide line values and protect ground waters.