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Background: The phenomenon of dust is a serious environmental problem in dry and semi dry regions. It has a destructive effect for the residents of such regions. Over two-thirds of Iran is in areas of dry and semi-dry climate conditions. Methods: In this research, dust fall measurements were taken in 41 stations across Yazd city using a marble dust collector (MDCO) located in different parts of the city. Next, the chemical characteristics of dust were determined using the XRF method. Finally, levels of dust fall across the 4 seasons of the year and status of the constituent elements of dust were determined through ArcGIS software and the Kriging technique. The Raster calculator function was used to make determinations of the effects of dust fall at each of the stations over the course of the year. Remote sensing system, along with maps taken from Landsat and the band combination technique were processed using ENVI software to extract vegetation density and building density maps of the studied region. Results: Results showed that spring had the highest level of dust fall with a value of 200 g/cm2. In total, in 109 km2 of the studied region had average dust fall of 110 g/m2 that contributed to 12 057 tons of dust over Yazd city in 2015. The constituent elements of the dust fall according to decreasing amounts were as follows: Si>Ca>Al>C>Mg>Fe>K>Na>S>Ti>Cl>P>Mn>Sr>Zn. Conclusion: These results indicate accuracy of the Kriging technique for application in dust zoning. The factors of vegetation and green space were determined as effective on adsorbing dust. Increased building density and height of buildings also contributed to development of dust fall. Keywords: ArcGIS, ENVI, Remote sensing, Air pollution, Dust fall, Zoning

Introduction: Health monitoring and control of food preparation, supply and distribution centers are the responsibility of environmental health officers. Therefore, the present study was conducted to explain the interaction between environmental health officers and providers of food preparation based on the game theory model. Materials and Methods: This research is a descriptive-analytical study in which after the determination of effective factors on the interaction between officers and directors, the so-called 22 games were designed and for each game four behavioral strategies determined and strategies identified as a two-choice I agree, I disagree questionnaire provided to environmental health officers and directors of food preparation, centers to select their desired strategy.. In the quantitative phase, SPSS 22 was used to analyze the data collected by questionnaires in order to determine the percentage of response frequency to each question. Gambit software was used to analyze for determination Nash equilibrium of any Games. Results: In the present study, the factors affecting the interaction between environmental health officers and directors were categorized to 24 subcategories assigned to six categories, and in the quantitative phase, finally, 22 dominant behavior strategies were identified and the final benefit percentage of each actor was determined. Conclusion: Investigating selected strategies by directors suggests that there is a good fit between the rules and health behaviors among the directors. The emphasis on health inspection based on education and counseling and lack of acceptance of the activities of health self-reported companies by the directors and officers are the most important outcomes of this study

Background: Global occurrence of foodborne illnesses is of public health importance in both developed and developing countries. This study aimed to assess the food safety knowledge, attitude, and hygiene practices (KAP) among veterinary medicine students in Shiraz University. Methods: This cross-sectional study was conducted from April to June 2017 using structured questionnaires on food safety KAP. Data were collected from 210 undergraduate veterinary medicine students from the Shiraz University, Iran. Data analysis was conducted using descriptive statistics, t-test, and ANOVA at the significant level of 0.05 by SPSS version 24. Results: The mean scores of KAP of students were 12.05 ± 1.46, 58.67 ± 15.09, and 49.32 ± 18.19, respectively. Results revealed that various age categories and years of education were significantly different from the mean score of knowledge. Conclusion: Regarding the food safety, the levels of knowledge, attitudes, and practice of students were moderate. So, it is necessary to raise the knowledge, change the attitudes, and promote the food safety practices of students.

Introduction: By increasing the amount and diversity of bio-environmental wastewater pollutants, it is essential to be controlled and planed the environmental contaminants to eliminate or minimize. Cardboard recycling industry wastewater has the potential of environmental pollution; it is contaminated with various fungal species that may be effective in the decomposition and removal of pollutants. The aim of this study was the isolation and identification of native fungal species that decontaminate organic pollutants in the cardboard recycling industry wastewaters. Methods: In this study, which is a descriptive study, samples were randomly taken from different area of wastewater of cardboard recycling industry. Samples were cultured on Saboraud dextrose agar medium for isolation of probable fungal species, which decomposers of wastewater. The isolated fungal colonies were enumerated and purified based on morphological characteristics and microscopic analyzing as far as possible. Results: The average count of the total number of fungi species in wastewater of cardboard recycling industry was 2.5×102 CFU/ml of these 2.1×101 were saprophytic fungi. The most prevalent fungal species were identificated from the wastewater include Aspergillus niger, Aspergillus flavus, Penicillum, Geotrichum, Mucor, Drechselera, Paecillomyces, Alternaria, Fusarium and Absidia. The highest frequency of fungal species Aspergillus nige, Aspergillus flavus and Penicillum were 30.89%, 22.76% and 14.63% respectively. Conclusion: It seems that native fungi isolated from the cardboard recycling industry wastewater in this study are from fungi that have the potential for bioremediation of wastewater contaminants based on scientific literature and can be used for evaluating of their ability to decompose wastewater from this industry.

Introduction: The International Standard Organization created a set of specified standards titled ISO 14000 in 1996 which includes numerous advisory documents related to the environment management, environment supervision, environmental performance evaluation, ecologic labeling, life cycle evaluation and environmental aspects. Materials and Methods: This is a descriptive-analytical cross sectional study. The population being studied includes the managers and the staff of Jiroft hospitals. The required data are collected using standard questionnaires of environmental management system from 118 managers and staff in various sections of Jiroft hospitals. Results: The results of the study show that the laboratory, laundry and kitchen condition, water management, contaminants management and spreading to the air, as well as environmental strategies in attaining green hospital standards in Jiroft hospitals, in accordance with ISO 14000, are suitable and at the optimum level. Conclusion: Hospital and health systems can improve their economic and moral situations in the society by helping to attain the goals of the millennium development in the field of health and stability as well as green economic.

Introduction: Zarrin Dasht is one of the low rainy areas of Fars province, which has faced repeated droughts in recent years. The aim of this study was to investigate the effect of education on the tendency towards water use efficiency in housewives of Zarrin Dasht. Materials and Methods: In this semi-experimental study, 130 patients (65 cases and 65 controls) were selected from housewives of Zarrin Dasht by cluster random sampling from four health centers. Data collection instrument was a standard, two-part questionnaire (demographic data and water saving tendency) that was a water saving standard. Data were analyzed by SPSS version 24 software. Results: The results of this study showed that the intervention was effective on the tendency of housewives to water use efficiency. There was a significant difference between the above variables before and after the intervention in the intervention group, and the relationship between age and occupation, and tendency to water use efficiency was statistically significant. Conclusion: Considering that education has a positive effect on women's tendency to water use efficiency, so providing water management education to housewives can lead to modification of consumption pattern.

2,4-Dichlorophenoxyacetic acid (2,4-DPAA) as a commonly used herbicide in agricultural farms causes severe contamination of groundwater and surface water. Herein, a treatment process based on the electro-Fenton (EF) technique was developed for efficient removal of 2,4-DPAA from agricultural wastewater. Response surface methodology (RSM) was employed to optimize the operation conditions and modeling the developed process. The best removal efficiency of 99.2% was achieved at solution pH of 3, initial 2,4-DPAA concentration of 2.6 mg L−1, H2O2 dosage of 470 µL L−1, the current density of 3.5 mA cm−2, and reaction time of 7.5 min, which is in good accordance with the predicted removal efficiency of 98.6% by the model. The developed process was applied successfully for removal of 2,4-DPAA from agricultural wastewater with the actual removal efficiency of 93.7%. The values of coefficients of determination (R2), predicted R2 and adjusted R2 were found to be 0.9775, 0.9268, and 0.9690, respectively. Analysis of variance (ANOVA) was conducted to evaluate the competence of the developed model. The obtained high F-value of 114.14 and the very low P-value of

Hexavalent chromium has been proved to be the reason of several health hazards. This study aimed at evaluating the application of pomegranate seeds powder for chromium adsorption (VI) from aqueous solution. Chromium adsorption percentage (VI) increased with increasing the adsorbent dosage. Chromium adsorption capacity (VI), at pH = 2 and 10 mg/L initial metal concentration, decreased from 3.313 to 1.6 mg/g through increasing dosage of adsorbent from 0.2 to 0.6 g/100 ml. The adsorption rate increased through increase in chromium initial concentration (VI). However, there was a removal percentage reduction of chromium (VI). Chromium adsorption kinetics by different models (pseudo-first-order, modified pseudo-first-order, pseudo-second-order, Elovich, intraparticle diffusion, Boyd kinetic) was investigated as well. Studies on adsorption kinetic indicated that the experimental data were matched by pseudo-second-order model (R 2 = 0.999) better. Obtained results demonstrated the pomegranate seeds can be used as an effective biomaterial and biosorbent for hexavalent chromium adsorption from aqueous solutions.

In this study, the application of adsorption processes on the surface of TiO2 nanoparticles and oxidation by O3, UV, O3/TiO2, and the UV/TiO2 in the removal of reactive red 198 dye form textile wastewater was examined. Then, Analytical Hierarchy Process (AHP) was used to choose the best removal method. The studied criteria for decision-making in selecting the best choice included the rate of dye removal in different situations, with the sub-criteria of studied variables, cost, with the sub-criteria of initial operation and maintenance cost, and the required expertise to use each method. Grading and preference of each method were calculated based on the efficiency of removal in different conditions, the price of each tool in the market, and the consumed energy of each method. The UV/TiO2 process was considered as the best-known method based on AHP model. Results indicated that this model can be a useful and suitable tool for policy-makers and decision-makers to choose the best treatment process in ...

Despite many efforts to remove humic acid (HA) in water resources, this problem is not overcome, especially in underdeveloped countries. The aim of this study is to evaluate the effects of inorganic anions (Cl−, , , and ) as radical scavenger on the efficacy of electron beam (EB) irradiation for the removal of HA from aqueous solutions. In this study, stock HA solution was prepared in alkaline condition; furthermore, different concentrations of anions were added to all HA samples. Here, the effect of different electron beam absorbed doses (1, 3, 6, 9, and 15 kGy) on the removal of HA is studied. HA concentration was measured using UV–vis spectrophotometer at 254 nm. The results showed that by increasing absorbed dose from 1 to 15 kGy, HA removal efficiency increased from 28.2 to 77.7%, respectively. While, by increasing different inorganic anion concentrations from 25 to 100 mg/L, the removal efficiency decreased. According to the results, nitrate has more inhibitory effect on the hydroxyl free ra...

In the present study, TiO2/ZnO-supported phosphomolybdic acid nanoparticles are investigated by the impregnation method, followed by analyzing their photocatalytic activity under UV-LED light and degradation kinetics degrading aniline as an organic pollutant model. Nanoparticle characteristics and the remaining Keggin structure in the nanocomposites were confirmed by means of FESEM, FTIR, and XRD analyses. Heterogenization of phosphomolybdic acid on TiO2 and ZnO nanoparticles resulted in the improved light absorption intensity and decreased band gap of nanocomposites. Photocatalytic degradation of aniline was also improved for composite nanoparticles and reached to 25.62, 43.48, and 38.25% for TiO2/HPMo, ZnO/HPMo, and TiO2/ZnO/HPMo, respectively. Overall, the results showed a good fit to the Langmuir-Hinshelwood kinetic model.

In this study, for the first time the potential use of activated carbon provided from Tamarix hispida (ACTH) to remove Zn(II) from wastewater was investigated by considering parameter optimization, reusability, equilibrium, kinetic, and thermodynamic aspects. The ACTH was mesoporous adsorbent with a specific surface area of 1006 m 2 /g. The main parameters in the adsorption process including pH, contact time and Zn(II) concentration, adsorbent dose, mixing rate, and temperature were considered. Over 95% of 70 mg/L Zn(II) was adsorbed using 10 g/L ACTH at the solution pH of 6. The Zn(II) adsorption onto ACTH increased from 93.2% to 98.33% by increasing the solution temperature from 10 to 50 °C. The ACTH was more efficient than the standard activated carbon. The results showed that the equilibrium adsorption of Zn(II) onto ACTH were well described by the Langmuir model. According to this model, the maximum adsorption capacity was found to be 246.4 mg/g. The nonlinear kinetic data were best fitted to the pseudo-second order model. The ACTH had acceptable performance after 4 times recycling. The suitability of ACTH in the treatment at field conditions was investigated with an industrial wastewater samples collected from a local plating wastewater. Based on the study’s results, the ACTH was shown to be an affordable and a promising option for adsorbing zinc ions from wastewaters.

Background: Cosmetics use is universal and Iran is the 3rd biggest user of cosmetic products among the Middle East countries. Using cosmetics can be associated with multiple adverse reactions from less severe local reactions to systemic reactions and serious complications. Objectives: The aim of the study was to explore the knowledge, attitudes, and practices of women in the city of Yazd about adverse effects of cosmetics. Methods: A cross-sectional study was conducted on 200 women in the city of Yazd in 2011. Data were collected through a researcher-designed questionnaire for assessing participant’s knowledge, attitude, and practice. Data were tabulated and analyzed by SPSS, using descriptive analysis and Pearson’s correlation coefficient. Results with a P value of less than 0.05 were considered statistically significant. Results: The mean score of participants’ knowledge about using cosmetics was 5.95 ± 2.47 (ranging 0 to 14). The mean score of attitude and practice about using cosmetics were 31.80 ± 3.96 (ranging 21 to 40) and 12.92 ± 2.83 (ranging 4 to 18), respectively. There wasn’t a significant correlation between participants’ knowledge and practice, however, there was a positive significant correlation (P = 0.01, r = 0.248) between their knowledge and attitude. Results showed a positive statistically significant correlation between attitude and practice with age (r = 0.168 and 0.139, respectively). Conclusions: Women had low level of knowledge about adverse effects of cosmetics. Practice of women was also unfavorable. Therefore, there is a need to educate women about the possible risks of cosmetics through formal channels.

The efficiency of photocatalytic oxidation process in arsenite (As(III)) removal from contaminated water by a new Fe

The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventional monitoring method (According to ISIR (Institute of Standards and Industrial Research of Iran), 1053 and 4208) and use of electronic system method (Patent in industrial property general office of Iran, 77815). Free chlorine monitoring and pH test done by health workers in the conventional method and the results will be sent to the Health Network monthly. Sampling for microbiological testing is done monthly based on population (According to ISIR, 4208). On the electronic system, the procedure is also done by health workers, but the result will be sent to the receiver device by using a cell phone. According to the chlorine test results if the free chlorine residual reported zero, microbiological sampling was done by a health expert. Finally, the number of chlorine test and microbiological sampling and the results of these experiments collected in the both methods and recorded in SPSS 22 then were analyzed by using chi-square test and Fisher exact test. The result of microbiological experiments shows that the sampling rate decreased 29% in using of electronic system method in comparison to the conventional monitoring method while the number of microbial defect detection increased 19% in drinking water networks monitoring by electronic system. Using of electronic system monitoring can reduce the rate and cost of microbiological sampling and its experiments and increase accuracy of these tests, in this way it will increase the quality and safety of drinking water in distribution network in small and dispersed rural communities.

In the present study, TiO

In this study, an anaerobic moving bed biofilm reactor (AMBBR) was designed to biodegrade atrazine under mesophilic (32 °C) condition and then it was evaluated for approximately 1 year. After biofilm formation, acclimation, and enrichment of microbial population within the bioreactor, the effect of various operation conditions such as changes in the concentration of influent atrazine and sucrose, hydraulic retention time (HRT), and salinity on the removal of atrazine and chemical oxygen demand (COD) were studied. In optimum conditions, the maximum removal efficiency of atrazine and COD was 60.5% and 97.4%, respectively. Various models were developed to predict the performance of atrazine removal as a function of HRT during continuous digestion. Also, coefficients kinetics was studied and the maximum atrazine removal rate was determined by Stover - Kincannon model (rmax = 0.223 kgATZ/m3d). Increasing salinity up to 20 g/L NaCl in influent flow could inhibit atrazine biodegradation process strongly in the AMBBR reactor; whereas, the reactor could tolerate the concentrations less than 20 g/L easily. Results showed that AMBBR is feasible, easy, affordable, so suitable process for efficiently biodegrading toxic chlorinated organic compounds such as atrazine. There was no accumulation of atrazine in the biofilm and the loss of atrazine in the control reactor was negligible; this shows that atrazine removal mechanism in this system was due to co-metabolism.

In this study employed an anoxic moving bed biofilm reactor (AnMBBR) to evaluate the effects of hydraulic and toxic shocks on performance reactor. The results indicated a relatively good resistance of system against exercised shocks and its ability to return to steady-state conditions. In optimal conditions when there was the maximum rate of atrazine and soluble chemical oxygen demand (COD) removal were 74.82% and 99.29% respectively. Also, atrazine biodegradation rapidly declines in AnMBBR from 74% ± 0.05 in the presence of nitrate to 9.12% only 3 days after the nitrate was eliding from the influent. Coefficients kinetics was studied and the maximum atrazine removal rate was determined by modified Stover & Kincannon model (U max = 9.87 g ATZ /m 3 d). Results showed that AnMBBR is feasible, easy, affordable, so suitable process for efficiently biodegrading toxic chlorinated organic compounds such as atrazine. Also, its removal mechanism in this system is co-metabolism.

Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD5, and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (vds/vtw) decreased a large extent to about 0.088%. In other words, the water reuse has increased to more than 99.91%. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption.

The heavy metals available in drinking water can be considered as a threat to human health. Oncogenic risk of such metals is proven in several studies. Present study aimed to investigate concentration of the heavy metals including As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in 39 water supply wells and 5 water reservoirs within the cities Ardakan, Meibod, Abarkouh, Bafgh, and Bahabad. The spatial distribution of the concentration was carried out by the software ArcGIS. Such simulations as non-carcinogenic hazard and lifetime cancer risk were conducted for lead and nickel using Monte Carlo technique. The sensitivity analysis was carried out to find the most important and effective parameters on risk assessment. The results indicated that concentration of all metals in 39 wells (except iron in 3 cases) reached the levels mentioned in EPA, World Health Organization, and Pollution Control Department standards. Based on the spatial distribution results at all studied regions, the highest concentrations of metals were derived, respectively, for iron and zinc. Calculated HQ values for non-carcinogenic hazard indicated a reasonable risk. Average lifetime cancer risks for the lead in Ardakan and nickel in Meibod and Bahabad were shown to be 1.09 × 10−3, 1.67 × 10−1, and 2 × 10−1, respectively, demonstrating high carcinogenic risk compared to similar standards and studies. The sensitivity analysis suggests high impact of concentration and BW in carcinogenic risk.

The antimicrobial activity of 4-amino-5-methyl-2H-1,2,4-triazole-3(4H)-thione (AMTT) and its silver(I) and copper(I) complexes has been investigated. Results show that MIC50 and MIC90 of the organic ligand against all test strains were higher than MIC50 and MIC90 of both complexes. The minimum MIC50 of the silver complex, copper complex, and the ligand against Candida albicans and Aspergillus niger were 5.6, 10.3, and 12.5 μg/mL, respectively. The MIC50 and MIC90 of the silver complex were lower than those of the copper complex against Candida albicans, Aspergillus niger, Escherichia coli, and Pseudomonas aeruginosa. At the same time, the MIC50 of the silver complex is higher than that of the copper complex against Staphylococcus aureus.

Pyrolysis of fresh sheep bone led to the formation of bone charcoal (BC). The structural characteristics of BC and surface area were determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). N2 gas adsorption-desorption was analysed by Brunauer-Emmett-Teller isotherm model. The prepared BC was used as an effective sorbent for the removal of phosphate from aqueous solutions. The effect of major parameters, including initial phosphorous concentration, sorbent dosage, pH and temperature, was investigated in this study. Furthermore, adsorption isotherms and kinetics were evaluated. BC was an effective sorbent in phosphate removal from aqueous solution especially in phosphate concentration between 2 and 100 mg/L. The maximum amount of sorption capacity was 30.21 mg/g, which was obtained with 100 mg/L as the initial phosphate concentration and 0.2 g as the sorbent dosage. Best reported pH in this study is 4; in higher pH, adsorption rate decreased dramatically. By increasing the temperature from 20 to 40 degrees C sorption capacity increased; this phenomenon described that adsorption is endothermic. Equilibrium data were analysed by Langmuir, Freundlich and Temkin isotherms. Pseudo first- and second-order and Elovich models were used to determine the kinetics of adsorption in this study. Collected data highly fitted with Freundlich isotherms and pseudo second-order kinetics. Achieved results have shown well the potentiality for the BC to be utilized as a natural sorbent to remove phosphorous from water and wastewater.

Dyes are complex organic materials which are important causes of environmental contamination. The purpose of this study was evaluation of the adsorption equilibrium and kinetics for bioadsorption of reactive red 198 dye from aqueous solutions by pomegranate seed powder. The effects of amount of adsorbent, initial dye concentration, and retention time were evaluated. Adsorption experiments were conducted under acidic conditions (pH 3). Pomegranate seeds were washed with distilled water, boiled for 2 h, dried in an oven, and milled, and the powder was passed through standard ASTM sieves (40–100 mesh). Experimental results were analyzed by use of the Langmuir and Freundlich isotherm models and the pseudo-first-order and pseudo-second-order kinetic models. According to the results, adsorption capacity (removal efficiency, %) for 0.2 g/100 cm3 adsorbent and initial dye concentrations 25 and 50 mg/l was 10.95 mg/g (87.64 %) and 17.75 mg/g (71 %), respectively. Results showed that increasing the amount of adsorbent and the retention time led to increased efficiency of dye removal, and that increasing the initial dye concentration led to reduced efficiency of dye removal. Maximum adsorption occurred after contact for 30 min. The experimental results were in good agreement with the Freundlich isotherm, and adsorption followed pseudo-second-order kinetics. On the basis of these results, this biosorbent enables effective removal of reactive red 198 dye.

In this study the removal of Cr (VI) from synthetic wastewater was investigated using Acroptilon repens (Russian Knapweed) flower powder under various conditions (pH, contact time and initial concentration of Cr). The capacity of chromium adsorption at equilibrium conditions by this biosorbent was increased by adsorbate concentration. The results also showed that the removal efficiency of Cr (VI) was increased by increasing the contact time. By increasing the initial concentration of Cr (VI) solution, chromium removal was reduced. The suitability of adsorbents and their constants was tested or evaluated with the Langmuir, Freundlich and Temkin isotherms models. The results indicated that the Freundlich and Langmuir models (R2 > 0.99) gave a better concordance to the adsorption data in comparison with the Temkin equation (R2 = 0.97). The adsorption of Cr (VI) followed the pseudo-second-order kinetics (R2 = 0.991). The study showed that Acroptilon repens flower powder can be used as an effective lignocellulosic biomaterial and biosorbent for the removal of Cr (VI) from wastewater.

Background and Objectives: Chromium is one of the most important heavy metals, which its high levels in drinking water lead to several health adverse effects. This study was performed aiming at determining the effects of primary concentration of six-valent chromium, adsorbent dosage, contact time, and pH on the adsorption of chromium from water on bone char. Methods: Bone char was prepared using electric furnace at 450 ° C for 2 h. Pulverizing of bone char was carried out by standard ASTM sieves with the range of 0.5-1 mm. The structural characteristics and specific surface area were determined through conventional methods. The samples' chromium concentration was measured at a wavelength of 450 nm. Adsorption isotherm of chromium was assessed by Freundlich, Langmuir, and Temkin adsorption equation models. Results: The main component of Bone char is calcium hydroxylapatite with surface area of 100m 2 /g. In this study, adsorption reached the equilibrium at lapse of 120 min, and the increase of adsorbent dose up to 0.7g/100ml leaded to increase in the chromium adsorption. However, higher level had no effect on adsorption efficiency. The results showed optimum adsorption took place better in acidic range of pH (pH=3). Adsorption isotherm of chromium on bone char follows the Langmuir and Temkin models, and the maximum adsorption capacity the dimensionless coefficient (R L ) were 2.025 mg/g and 0.15, respectively which indicates that an appropriate adsorption of chromium on bone char. Conclusion: Bone char is an inexpensive adsorbent, which can be used for adsorption of chromium from water based on surface properties.

Diazinon is an organophosphate compound that inhibits the activity of acetylcholinesterase. Standards of the World Health Organization and Environmental Protection Agency for diazinon concentration in water are 0.1 and 9 × 10−6 mg/L, respectively. The aim of this study was the optimization of diazinon biodegradation from aqueous solutions by Saccharomyces cerevisiae using the response surface methodology (RSM). Harvested cells of S. cerevisiae were locally purchased from the Iranian Research Organization for Science and Technology. To obtain the optimum condition for diazinon biodegradation using RSM, input parameters included the initial concentration of diazinon (0.01–10 mg/L), concentration of S. cerevisiae (0.5–5%), pH (4–10), and retention time (1–30 h). The research study had a central composite design where one of the methods was RSM. According to the results, the observed values of the removal efficiency of diazinon were variable in the range of 23–96. The highest removal rate was obtained as 96% under the initial diazinon concentration of 2.5 mg/L, S. cerevisiae concentration of 3.88%, pH of 5.5, and retention time of 22.75 h. The results displayed that the removal efficiency of diazinon had a direct relationship with the concentration of S. cerevisiae and retention time, and an inverse relationship with pH and the initial concentration of diazinon. We can conclude that S. cerevisiae has the ability to remove diazinon with the lowest cost and a high efficiency.

In this study, performance of Integrated Fixed-film Activated Sludge (IFAS) system in treatment of Linear Alkylbenzene Sulfonate (LAS), and oil & grease in synthetic greywater and effect of Organic Loading Rates (OLRs) on removal efficiency within a period of 105 days were investigated. Present study was carried out in a pilot scale under such conditions as temperature of 30 ± 1 °C, dissolved oxygen of 2.32 ± 0.91 mg/l, pH of 8.01 ± 0.95 and OLRs of 0.11-1.3gCOD/L.d. Also, Scanning Electron Microscopy (SEM) images were employed to specify rate of the biofilm formed on the media inside the reactor IFAS. The best removal efficiency for COD, LAS and oil and grease were respectively obtained as 92.52%, 94.24% and 90.07% in OLR 0.44gCOD/L.d. The assessment of loading rate indicated that with increased OLR to 0.44gCOD/L.d, removal efficiency of COD, oil and grease was increased while with increased OLR, removal efficiency was decreased. In doing so, based on the statistical test ANOVA, such a difference between removal efficiencies in diverse OLRs was significant for COD (p = 0.003), oil and grease (p = 0.01). However, in terms of LAS, with increased value of OLR to 0.44gCOD/L.d, the removal efficiency was increased and then with higher OLRs, removal efficiency was slightly decreased that is insignificant (p = 0.35) based on the statistical test ANOVA. The SEM images also showed that the biofilm formed on the media inside IFAS reactor plays a considerable role in adsorption and biodegradation of LAS, and oil & grease in greywater. The linear relation between inlet COD values and rate of removed LAS indicated that the ratio of inlet COD (mg/L) to removed LAS (mg/L) was 0.4. Therefore, use of IFAS system for biodegradation of LAS, oil and grease in greywater can be an applicable option.

Poor air quality is one of the most important environmental problems in many large cities of the world, which can cause a wide range of acute and chronic health effects, including partial physiological disorders and cardiac death due to respiratory and cardiovascular diseases. According to the latest edition of the national standard for air quality, maximum contamination level is 15 μg/m(3) per year and 35 μg/m(3) per day. The aim of this study was to evaluate cardiovascular, respiratory, and total mortality attributed to PM2.5 in the city of Mashhad during 2013. To this end, the Air Q model was used to assess health impacts of PM2.5 and human exposure to it. In this model, the attributable proportion of health outcome, annual number of excess cases of mortality for all causes, and cardiovascular and respiratory diseases were estimated. The results showed that the number of excess cases of mortality for all causes and cardiovascular and respiratory diseases attributable to PM2.5 was 32, 263, and 332 μg/m(3), respectively. Moreover, the annual average of PM2.5 in Mashhad was obtained to be 37.85 μg/m(3). This study demonstrated that a high percentage of mortality resulting from this pollutant could be due to the high average concentration of PM2.5 in the city during 2013. In this case, using the particle control methods, such as optimal use of fuel, management of air quality in urban areas, technical inspection of vehicles, faster development of public transport, and use of industrial technology can be effective in reducing air pollution in cities and turning existing situations into preferred ones.

Background: The chemical and physical quality of water used for dialysis fluid is a vital factor in the patients overall care who receive dialysis. Therefore, the water used for this purpose must be treated with advanced methods before being used for dialysis. Objectives: The current study aimed to determine the chemical and physical quality of dialysis machines input water and compare it to the standards of Association for the advancement of medical instrumentation (AAMI) and European Pharmacopeia (EPh) in Yazd educational hospitals, i.e. Shahid Sadoughi and Shahid Dr. Rahnamoon. Materials and Methods: This cross-sectional study is performed in three months (October to December) in 2013. This research was conducted on 24 samples of dialysis machines input water. The samples were tested by titrimetric method, turbid metric method, flame photometer, pH meter, and EC meter. The SPSS V16.0 software was used for statistical analyses. Results: Based on results of the research, except chloride that its mean concentration was higher than the EPh standard, mean concentrations of cations and other compounds were significantly less than the standards (P < 0.01). Also there was a significant difference between the measured parameters in the dialysis machines input water in two educational hospitals with 99% confidence. Conclusions: The evaluation of hemodialysis water quality showed that these hospitals were not significantly polluted and the water quality complied with AAMI and EPh standard limits.

Nano-sized flower-like Ag/ZnO was synthesized by a simple method using zinc acetate and silver acetate under hydrothermal condition. Powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM) were used to characterize the structure and morphology of the synthesized powder. Nano flower-like Ag/ZnO was used as a photocatalyst for degradation of humic acid in aqueous solution. The disappearance of HA was analyzed by measuring the absorbance of sample at special wavelength (254 nm). The effects of various parameters such as amount of photocatalyst, pH, initial humic acid concentration and irradiation time on degradation rate were systematically investigated. Photodegradation efficiency was small when the photolysis was carried out in the absence of Ag/ZnO and it was also negligible in the absence of light. Approximately 70% of humic acid (50 mg/L) has been eliminated after 40 minutes in the presences of catalyst (catalyst dose o.6 g/L and pH =7) and UVA irradiation. While, 100% of humic acid has been eliminated with solar irradiation.

Background: Sick Building Syndrome is a diseases associated with indoor air quality accompanied with symptoms such as headache, dizziness, nausea, coughing and sneezing, irritation of eyes, throat and nose mucous membrane, and skin itching and inflammation. The purpose of this study was to investigate the symptoms of the syndrome and its related factors among nurses in teaching hospitals of Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Methods: The study was conducted amongst nurses of three teaching hospitals of Shahid Sadoughi University of Medical Sciences, in Yazd. In this study the MM040EA questionnaire of sick building syndrome and indoor air quality was used and data extracted from the questionnaires were analyzed using the chi-square test and t-test. Results: The prevalence of sick building syndrome was 86.4%. The prevalence of the syndrome was in no association with age, gender, employment history and type of shift work. The most common symptoms reported by nurses included headache, fatigue and dry hands. Lack of sense of airflow, unpleasant odor in workplace (P

A separation technique which has recently received a sharp increase in research activities is “ion flotation”. This technique has four important advantages for treating wastewaters: low energy consumption, small space requirements, small volume of sludge and acting selectively. The present study aims to optimize parameters of ion flotation for cadmium removal in simulated wastewater at laboratory scale. It was obtained on the reaction between Cd2+ and sodium dodecylesulfate (SDS) collector followed by flotation with ethanol as frother. Test solution was prepared by combining the required amount of cadmium ion, SDS and necessary frother or sodium sulfate solution. All experiments were carried out in a flotation column at laboratory temperature (27°C), adjusted pH = 4 and 120 minutes. The different parameters (namely: flow rate, cadmium, SDS and frother concentrations and ionic strength) influencing the flotation process were examined. The best removal efficiency obtained at a collector-metal ratio of 3:1 in 60 min with flow rate of 150 mL/min was 84%. The maximum cadmium removal was 92.1% where ethanol was introduced at a concentration 0.4% to flotation column with above conditions. The obtained results were promising, as both cadmium and collector were effectively removed from wastewater. Hence, the application of ion flotation for metal ions removal from effluents seems to be efficient.

Due to industrial development, lack of water resources on a global scale and increasing water demands in both rural and urban societies, quests for reviving water resources and finding reproducible ones have soared in recent years. Meanwhile, rainwater is one of the most accessible water resources in societies with high rainfall seasons which could be utilized as a sustainable and reproducible resource of water supply. Average amount of TDS (Total Dissolved Solids) in surface water is about 300 MgL, while for ground water is usually more than 1000 MgL. Rain water contains very low amount of TDS (0-10) MgL. Besides the biological effects of low TDS water on the body, problems of taste and odour are always being reported by consumers. Mixing rainwater with water from other resources with higher TDS is one of the proposed solutions to solve this problem. In this research, we at first try to gather information about acceptability of rainwater quality (taste, hardness etc.) by questionnaire from the inhabitant of villages in the study area. Results indicated that more than 85 percent of inhabitants were displeased with the water quality. Then samples were analyzed to obtain primitive amount of physicochemical parameters and mixed with water from surface and underground resources in 3 ratio (1/10, 2/10and 3/10) to obtain the best ratio of mixing for providing water with optimum TDS and TH. After statistical analysis of data, 2/10 mixing ratio was picked as the optimum rate in this experiment. By utilizing 2/10 mixing ratio with surface water (S/R), final TDS of rainwater was increased up to (80-94) MgL and TH up to (73-89) MgLcaco3, While this value is about (121-159) MgL for TDS, Water Resources Management VI 395 www.witpress.com, ISSN 1743-3541 (on-line) WIT Transactions on Ecology and the Environment, Vol 145, © 2011 WIT Press doi:10.2495/WRM110341 besides (125-141) MgLcaco3 for TH by utilizing the same ratio of mixing with ground water (G/R).

Lack of water supply in recent years is one of the significant problems of both rural and urban societies, as water is one of sustainable development pillars. in societies with high rainfall seasons rainwater is one of the most accessible water resources, which could be utilized as sustainable and reproducible resource of water supply. As rain water contains very low amount of TDS (0-10) MgL−1 there is a need to modify rainwater TDS in order to make it potable. Besides biological effect of low TDS water on body, taste and odour problems always are reported by inhabitant of region. Mixing rainwater with water from other resources with higher TDS is one of the proposed solutions to solve this problem. In the study area samples from rainwater were grabbed and mixed with surface and groundwater after gathering information from inhabitant of region, results indicated that more than 85 percent of inhabitants were displeased of water quality. At first Samples were analyzed to obtain primitive amount of physicochemical parameters and mixed with water from surface and under ground resources in 3 ratio (1/10, 2/10and 3/10) to obtain the best ratio of mixing for providing water with optimum TDS and TH.

The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of hydrogen peroxide and potassium persulphate, as electron acceptors, into illuminated TiO2 nanofibre suspensions, a synergistic effect was observed leading to an enhancement of the decolorization. From experimental results, under the condition of 1 g TiO2 nanofibre l(-1), pH 3, and UVC light irradiation, decolorization would be complete in two hours. A significant decrease in the COD values was observed, which clearly indicates that the photocatalytic method offers good potential for the removal of RB19 from aqueous solution. The kinetic of photocatalytic removal of RB19 followed the Langmuir-Hinshelwood model. These results suggest that TiO2 nanofibres with UV photocatalysis can be envisaged as a method for the treatment of coloured wastewaters, in particular in textile industries.

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 (λmax ) 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.