Publications by authors named "Hadi Eslami"

20 Publications

  • Page 1 of 1

Comparison of poly ferric chloride and poly titanium tetrachloride in coagulation and flocculation process for paper and cardboard wastewater treatment.

Environ Sci Pollut Res Int 2021 Jan 28. Epub 2021 Jan 28.

Occupational Health and Safety Research Center, NICICO, World Safety Organization and Rafsanjan University of Medical Sciences, Rafsanjan, Iran.

The current study investigated the efficiency of poly ferric chloride (PFC) and poly titanium tetrachloride (PTC) in coagulation-flocculation process for treatment of paper and cardboard wastewater. The effect of pH (5-11), coagulant concentrations (100-1000 mg/L), mixing rate (10-60 rpm), mixing time (5-25 min), and settling time (5-30 min) were examined. The results showed that the removal efficiency for turbidity, total suspended solids (TSS), and chemical oxygen demand (COD) by PFC and PTC coagulants increased with pH rising up to 9 for the former and 7 for the latter coagulant. Furthermore, the removal efficiency for the afore-mentioned parameters increased along with a 30 rpm increase in the mixing rate, while the mixing time reached 20 min. It was also found that the best removal efficiencies for turbidity, TSS, and COD by PFC under optimal conditions (pH 9, coagulant dose 800 mg/L, and settling time of 25 min) were 97.11%, 99.1%, and 84.91%, respectively. In addition, the removal efficiencies for PTC (optimal conditions of pH 7, coagulant dose 600 mg/L, and settling time of 15 min) were found to be 98.29%, 99.29%, and 86.42%, respectively. Water recovery and the produced sludge volume by PFC were 80% and 200 cm, respectively, in the settling time of 25 min and for PTC were 81.5% and 185 cm, respectively, in the settling time of 15 min. Costs of the coagulation-flocculation process for treatment 1 m of paper and cardboard wastewater using PTC and PFC were 0.42 $ and 0.32 $, respectively. Finally, it can be concluded that compared to PFC, PTC with higher settling rate has a greater efficiency for treatment of paper and cardboard wastewater.
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http://dx.doi.org/10.1007/s11356-021-12675-6DOI Listing
January 2021

Adsorption of Pb (II) and Zn (II) ions from aqueous solutions by Red Earth.

MethodsX 2020 23;7:100804. Epub 2020 Jan 23.

Department of Environmental Health Engineering, School of Health, Rafsanjan University of Medical Science, Rafsanjan, Iran.

This study was carried out to investigate Pb (II) and Zn (II) removal from aqueous solutions by Red Earth (RE) as a new local natural adsorbent in using the batch method. The chemical structure of RE adsorbent was characterized by XRF. Giles, Langmuir, and Freundlich isotherms were used to describe the adsorption data. The effect of metals concentration, initial pH, adsorbent dosage, and agitation time were studied. The results showed that RE contains of SiO (58 %) and AlO (15.2 %) as major compounds. The equilibrium time was reached following 30 min and the maximum adsorption capacities (mg/g), based on Langmuir equation were 10.31 and 8.74 for Pb (II) and Zn (II), respectively. By increasing the initial metal ions concentration, the adsorption efficiencies were decreased and adsorption capacity of RE increased with an increase in the initial pH.
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http://dx.doi.org/10.1016/j.mex.2020.100804DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7794614PMC
January 2020

The role of environmental factors to transmission of SARS-CoV-2 (COVID-19).

AMB Express 2020 May 15;10(1):92. Epub 2020 May 15.

Environmental Science and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Pardis Campus, Gomnam Blv, Alem Squre, Yazd, Iran.

The current outbreak of the novel coronavirus disease 2019 (COVID-19) in more than 250 countries has become a serious threat to the health of people around the world. Human-to-human transmission of the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurs most often when people are in the incubation stage of the disease or are carriers and have no symptoms. Therefore, in this study, was discussed the role of environmental factors and conditions such as temperature, humidity, wind speed as well as food, water and sewage, air, insects, inanimate surfaces, and hands in COVID-19 transmission. The results of studies on the stability of the SARS-CoV-2 on different levels showed that the resistance of this virus on smooth surfaces was higher than others. Temperature increase and sunlight can facilitate the destruction of SARS-COV-2 and the stability of it on surfaces. When the minimum ambient air temperature increases by 1 °C, the cumulative number of cases decreases by 0.86%. According to the latest evidence, the presence of coronavirus in the sewer has been confirmed, but there is no evidence that it is transmitted through sewage or contaminated drinking water. Also, SARS-COV-2 transmission through food, food packages, and food handlers has not been identified as a risk factor for the disease. According to the latest studies, the possibility of transmitting SARS-COV-2 bioaerosol through the air has been reported in the internal environment of ophthalmology. The results additionally show that infectious bio-aerosols can move up to 6 feet. There have been no reports of SARS-COV-2 transmission by blood-feeding arthropods such as mosquitoes.
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http://dx.doi.org/10.1186/s13568-020-01028-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7226715PMC
May 2020

Opium Use and Head and Neck Cancers: A Matched Case-Control Study in Iran.

Asian Pac J Cancer Prev 2020 03 1;21(3):783-790. Epub 2020 Mar 1.

Department of Otorhinolaryngology Head and Neck Surgery, Shafa Hospital, Kerman University of Medical Sciences, Kerman, Iran.

Background: Head and Neck (H and N) cancers include malignant tumors of the nasal cavity, pharynx, paranasal sinuses, oral cavity, larynx and salivary glands. Opium use might be related to these cancers. The aim of this study was to investigate the relation between Opium and its Derivatives (O and D) use and the incidence of H and N cancers.

Methods: In this case-control study conducted in Kerman, 140 patients with HandN cancers and 280 healthy controls (matched for age, gender, and place of residence) were included. Information about their use of O and D, cigarette smoking, alcohol and diet were collected using a structured questionnaire. Conditional logistic regression was used to investigate the relation between variables.

Results: The use of opioids was associated with an increased risk of H and N cancers (Adjusted OR: 8.13; CI: 4.08-16.2). A significant dose-response relation between O and D use was observed, with high use Adjusted OR=8.91; 95% CI: 4.03-19.65 and low use Adjusted OR=6.52; 95% CI: 3.18- 13.36. This dose-response association was stronger in patients with laryngeal cancer and opioids use, with high use Adjusted OR = 11.17; 95% CI=4.48-28.09 and low use Adjusted OR = 9.46; 95% CI= 3.97- 22.52.

Conclusion: The results show that opium use can be considered as an important risk factor for H and N cancers. Also in Iran, opium seems to play a more important role than cigarette smoking.
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http://dx.doi.org/10.31557/APJCP.2020.21.3.783DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7437338PMC
March 2020

The relationship of indoor radon gas concentration with multiple sclerosis: a case-control study.

Environ Sci Pollut Res Int 2020 May 2;27(14):16350-16361. Epub 2020 Mar 2.

Environmental Science and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

This case-control study aimed to investigate the relationship of indoor radon gas concentration and residential building characteristics with mental health with multiple sclerosis (MS) in Yazd City, Iran. The participants included 45 patients with MS and 100 healthy individuals. The participants' socio-economic status and residential building characteristics were investigated using a questionnaire. The radon gas concentration was also measured by CR-39 detectors over a 6-month period. Furthermore, the participants' mental health data were collected using General Health Questionnaire (GHQ-28). The mean concentrations of radon gas were 66.77 and 65.33 Bq/m in the homes of patients with MS and healthy individuals, respectively, but the difference was not significant (p = 0.882). However, the radon gas concentration had a significant relationship with the building's age (p = 0.038), ventilation (p = 0.053), and cooling system (p = 0.021). A significant difference was observed between the two study groups in terms of the mental health (p = 0.018), depression (p = 0.037), somatic symptoms (p ≤ 0.001), and physical activity (p = 0.030). Since the indoor radon gas concentration did not have any significant relationship with MS prevalence, more studies are required in this regard, especially in long-term exposure.
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http://dx.doi.org/10.1007/s11356-020-08147-yDOI Listing
May 2020

Efficient removal of Pb() and Zn() ions from aqueous solutions by adsorption onto a native natural bentonite.

MethodsX 2019 10;6:1979-1985. Epub 2019 Sep 10.

Occupational Environment Research Center, Department of Environmental Health Engineering, School of Health, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.

The new Native Natural Bentonite (NNB) for adsorption of Pb() and Zn() ions from aqueous environments was investigated at 27 ± 1C by in batch laboratory experiments. Chemical and mineralogical structure of the NNB adsorbent was characterized by XRF and cation exchange capacity (CEC). The effect of pH, metals concentration, adsorbent dose, and agitation time were also studied. Langmuir and Freundlich isotherm and the Giles classification isotherm were used for describing the equilibrium data. The results show that the NNB contains silica (SiO) and alumina (AlO) as a major chemical compound. The maximum adsorption capacity (mg/g), based on Langmuir isotherm were 8.55 and 7.90 for Pb() and Zn(), respectively. Pb() and Zn() removal efficiency was increasing by increasing the initial pH of solutions, adsorbent dose, and contact time. Therefore, the results of this study show that the equilibrium is reached slowly (180 min), indicating the adsorption sites are not well exposed. By increasing the initial metals ion concentration, the capacity of adsorption decreased and the uptake of Pb() and Zn() per unit weight of the adsorbent (mg/g) increased. The adsorption efficiency of Pb() was higher than Zn().
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http://dx.doi.org/10.1016/j.mex.2019.09.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6812330PMC
September 2019

Developing a system dynamics model for prediction of phosphorus in facultative stabilization ponds.

AMB Express 2019 Sep 25;9(1):157. Epub 2019 Sep 25.

Department of Environmental Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran.

System dynamics is considered as a computer-aided approach to policy analysis and design. It includes the response and reaction of a system to external shocks. In the present research, following the sampling and testing phases, a system dynamics model was developed for modeling of phosphorus in facultative stabilization ponds. First, the scheme of soluble reactive phosphorous stock, its specifications and parameters were determined and created in the VenSim PLE 7.1 software. Then, mathematical relations were determined for each process. Finally, the model was calibrated and verified based on the data from the Yazd facultative ponds, Iran. Sensitivity analysis showed that the most important factors affecting phosphorus concentration in the ponds are the phosphorus settling rate, losses caused by algal respiration and excretion, while the losses caused by herbivorous zooplanktons, hydrolysis rate of inorganic carbon, and ratio of phosphorus to chlorophyll-a had the least importance. Results showed that, algal growth rate and phosphorus settling rate were important factors in phosphorus removal. Hence, with appropriate retention time in the pond, it can be managed more properly. The ratio of phosphorus to algae had less importance in the model. The ratio of carbon to phosphorus and rate of respiration of carnivorous zooplanktons did not affect the phosphorus concentration. It is recommended that this model can be used for pond management and overall assessment of facultative ponds.
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http://dx.doi.org/10.1186/s13568-019-0882-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6761211PMC
September 2019

Decolorization and biodegradation of reactive Red 198 Azo dye by a new Enterococcus faecalis-Klebsiella variicola bacterial consortium isolated from textile wastewater sludge.

World J Microbiol Biotechnol 2019 Feb 9;35(3):38. Epub 2019 Feb 9.

Environmental Science and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

The present study investigated biodegradation and removal of Reactive Red 198 (RR198) dye from aqueous environments using a new bacterial consortium isolated from textile wastewater sludge on laboratory scale via batch study. Two bacterial species, Enterococcus faecalis (EF) and Klebsiella variicola (KV), were identified after isolation, through biochemical assays, Polymerase chain reaction (PCR), and 16S rRNA gene sequencing. To determine their ability to biodegrade RR198 dye, physicochemical parameters, including bacterial concentration, time, pH, and temperature, were tested; the results showed that the best conditions included a bacterial concentration of 3.5 mL × 10 cells/mL and incubation time of 72 h. Under such conditions, the removal efficiency of RR198 dye at an initial concentration of 10-25 mg/L was more than 98%; however, for concentrations of 50, 75, and 100 mg/L, removal efficiency was reduced to 55.62%, 25.82%, and 15.42%, respectively (p = 0.005). The highest removal efficiency occurred at pH 8.0, reaching 99.26% after 72 h of incubation. With increasing the incubation temperature from 25 °C to 37 °C, removal efficiency increased from 71.71 to 99.26% after 72 h of incubation, and increasing the temperature from 37 to 45 °C, the removal efficiency was reduced (p ≤ 0.001). Therefore, the EF-KV bacterial consortium can be used for efficient removal of RR198 dye from textile effluent.
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http://dx.doi.org/10.1007/s11274-019-2608-yDOI Listing
February 2019

Toxicity evaluation and management of co-composting pistachio wastes combined with cattle manure and municipal sewage sludge.

Ecotoxicol Environ Saf 2019 Apr 17;171:798-804. Epub 2019 Jan 17.

Environmental Science and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Electronic address:

To manage the pistachio de-hulling waste (PW), investigated the co-composting process using a mixture of PW and cattle manure (CM) (5.5:10 dry weight) as well as PW and municipal dewatering sewage sludge (DSS) (1:10 dry weight) at the laboratory scale for 60 days. Compost toxicity was evaluated using the seed germination index (GI). The maximum temperatures in co-composting processes of PW+CM (51.9 °C) and PW+DSS (49.9 °C) were reported on the seventh day. The increase of temperature was higher in PW+CM and remained in the thermophilic phase for five days. In both reactors, the pH rates decreased, increased, and finally remained neutral. The C/N ratio decreased in both reactors, but the reduction rate was faster in the PW+DSS reactor. Sodium (Na%) and potassium (K%) contents were increased, while the concentrations of Cu, Zn, Fe, and Mn were decreased during the processes. The numbers of parasite eggs in the final composts of the reactors containing PW+CM and PW+DSS were zero and 8 Number/4gDW, respectively. The amounts of Salmonella were zero in the final products of reactors containing PW+CM and PW+DSS. The results of GI showed that the final compost of PW+CM process was not toxic for the plants, whereas the PW+DDS final compost was toxic. In conclusion, the co-compost product of the PW+CM reactor had higher quality than the PW+DSS reactor. So, it is suitable for PW management.
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http://dx.doi.org/10.1016/j.ecoenv.2019.01.056DOI Listing
April 2019

Optimization and economic evaluation of modified coagulation-flocculation process for enhanced treatment of ceramic-tile industry wastewater.

AMB Express 2018 Oct 17;8(1):172. Epub 2018 Oct 17.

Environmental Science and Technology Research Center, Department of Management of Health Services, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

Enhanced treatment of ceramic-tile industry wastewater was investigated by modified coagulation-flocculation process using combination of poly-aluminum chloride (PAC) with anionic (A), cationic polymer (C) and nonionic polymers. The effects of pH, PAC coagulant dose alone and with polymers dose in various combinations was studied by jar tests. To compare the removal efficiencies of turbidity, total suspended solids (TSS), chemical oxygen demand (COD), and color at different levels, we run multivariate analysis of variance. Regarding the economic evaluation, we applied the incremental cost-effectiveness ratio. PAC had the best performance in pH 7 and in optimal dose of 400 mg/L; so that removal efficiency of wastewater turbidity, TSS, COD and color were 99.63%, 99.7%, 47.5% and 50.38%, respectively. The best removal efficiency for wastewater turbidity, TSS, COD and color were 99.87%, 99.89%, 87.5% and 93.02%, respectively which were obtained by combination of anionic polymer (1.5 mg/L) with PAC (300 mg/L). Furthermore, with combination of PAC + anionic + non-ionic polymers, the removal efficiency for wastewater turbidity, TSS, COD and color were 99.93%, 99.94%, 88% and 94.57%, respectively. The imposed cost for treating one cubic meter of ceramic-tile wastewater treatment by PAC + anionic and PAC + anionic and non-ionic polymers in comparison with PAC alone was reduced to 22.96% and therefore economically more affordable for the tile industry wastewater treatment.
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http://dx.doi.org/10.1186/s13568-018-0702-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6192943PMC
October 2018

An overview report on the application of heteropoly acids on supporting materials in the photocatalytic degradation of organic pollutants from aqueous solutions.

PeerJ 2018 12;6:e5501. Epub 2018 Sep 12.

Department of Environmental Health Engineering, School of Public Health, Social Development & Health Promotion Research Center, Gonabad University of Medical Sciences, Gonabad, Iran.

Organic pollutants contaminate water resources and the environment when discharged into water streams. Also, the presence of these materials in incompletely treated or untreated wastewater leads to serious environmental hazards. The hydroxyl radicals and holes are regarded as the most oxidant species in the degradation of organic pollutants using the studied composites. The results of this review show that heteropoly acids on supporting materials could be considered as appropriate photocatalysts in the removal of organic pollutant from aqueous solutions.
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http://dx.doi.org/10.7717/peerj.5501DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6139020PMC
September 2018

Efficient photocatalytic oxidation of arsenite from contaminated water by FeO-MnO nanocomposite under UVA radiation and process optimization with experimental design.

Chemosphere 2018 Sep 18;207:303-312. Epub 2018 May 18.

Department of Biostatistics and Epidemiology, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Electronic address:

The efficiency of photocatalytic oxidation process in arsenite (As(III)) removal from contaminated water by a new FeO-MnO nanocomposite under UV radiation was investigated. The effect of nanocomposite dosage, pH and initial As(III) concentration on the photocatalytic oxidation of As(III) were studied by experimental design. The synthesized nanocomposite had a uniform and spherical morphological structure and contained 49.83% of FeO and 29.36% of MnO. Based on the experimental design model, in photocatalytic oxidation process, the effect of pH was higher than other parameters. At nanocomposite concentrations of more than 12 mg L, pH 4 to 6 and oxidation time of 30 min, photocatalytic oxidation efficiency was more than 95% for initial As(III) concentration of less than 500 μg L. By decreasing pH and increasing the nanocomposite concentration, the photocatalytic oxidation efficiency was increased. Furthermore, by increasing the oxidation time from 10 to 240 min, in addition to oxidation of As(III) to arsenate (As(V)), the residual As(V) was adsorbed on the FeO-MnO nanocomposite and total As concentration was decreased. Therefore, FeO-MnO nanocomposite as a bimetal oxide, at low doses and short time, can enhance and improve the efficiency of the photocatalytic oxidation and adsorption of As(III) from contaminated water resources. Furthermore, the energy and material costs of the UV/FeO-MnO system for photocatalytic oxidation of 1  mg L As(III) in the 1 L laboratory scale reactor was 0.0051 €.
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http://dx.doi.org/10.1016/j.chemosphere.2018.05.106DOI Listing
September 2018

Probabilistic risk assessment of exposure to fluoride in most consumed brands of tea in the Middle East.

Food Chem Toxicol 2018 May 19;115:267-272. Epub 2018 Mar 19.

Department of Environmental Health Engineering, Gonabad University of Medical Sciences, Gonabad, Iran. Electronic address:

The aim of this study was to evaluate the fluoride concentration in seven most consumed brands of tea in the Middle East which was imported to Iran through Zabol County. In the present study, the health risk of exposure to fluoride was estimated using a probabilistic approach. Monte Carlo simulation and sensitivity analysis were applied to quantify uncertainties in risk estimation. The highest mean and 95th percentile of chronic daily intake (CDI) was observed for children group. Iranian tea and Kenya tea had maximum CDI and target hazard quotient (THQ) values among studied brands of tea which followed by Green tea, Taksetare tea, Ceylan tea, Red tea, and White tea. These result indicated that there were significant risks of exposure to fluoride in most of studied brands of tea for children (THQ>1). Sensitivity analysis showed that fluoride concentration and daily intake were the most influential variables in three exposed populations. In conclusion, the fluoride concentration in some studied brands of tea is high and it put children at risk risks of exposure to fluoride.
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http://dx.doi.org/10.1016/j.fct.2018.03.023DOI Listing
May 2018

Biodegradation and nutrients removal from greywater by an integrated fixed-film activated sludge (IFAS) in different organic loadings rates.

AMB Express 2018 Jan 8;8(1). Epub 2018 Jan 8.

Environmental Science and Technology Research Center, Department of Environmental Health Engineering, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

In this study, the efficiency of Integrated Fixed-film Activated Sludge (IFAS) system in synthetic greywater treatment and nutrients removal was studied in duration of 105 days according to different Organic Loadings Rates (OLRs). The study was operated in pilot-scale and OLRs of 0.11-1.3 gCOD/L.d. Scanning Electron Microscope (SEM) image showed that the biofilm with a proper thickness was formed on IFAS reactor's media. The results indicated that the best removal efficiency of BOD, COD, and TSS were 85.24, 92.52 and 90.21%, respectively, in an organic loading of 0.44 gCOD/L.d. Then, with the OLR increased, the removal efficiencies of BOD, COD, and TSS increased as long as the organic loading reached 0.44 gCOD/L.d. But with the OLR increased more, the removal efficiency of these parameters decreased. The ANOVA statistical test results showed that the mean difference of removal efficiency in organic loadings for BOD (p ≤ 0.001) and COD (p = 0.003) was significant, while it was insignificant for TSS (p = 0.23). The best removal efficiencies of Total Nitrogen (TN) and Total Phosphorus (TP) were 89.60 and 86.67%, respectively, which were obtained at an OLR of 0.44 gCOD/L.d. By increasing OLR up to 0.44 gCOD/L.d, removal efficiencies of TN and TP increased, while the removal efficiency decreased with the OLR increased more, and this difference was statistically significant (p = 0.021). Finally, the results showed that the IFAS system provided a proper efficiency in treatment of the synthetic greywater and it could be used in a full scale.
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http://dx.doi.org/10.1186/s13568-017-0532-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5758483PMC
January 2018

Kinetics of biogas production and chemical oxygen demand removal from compost leachate in an anaerobic migrating blanket reactor.

J Environ Manage 2018 Jan 20;206:707-714. Epub 2017 Nov 20.

Kurdistan Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran. Electronic address:

In this study, laboratory anaerobic migrating blanket reactor (AMBR) with four units was used to reduce and remove COD leachate of composting process; it was also used to determine the kinetic coefficients of COD removal and biogas and methane gas production in several different OLRs. The maximum concentration of organic matter entering the reactor was 100,000 mg/L and the reactor was under operation for 319 days. The results showed that the COD removal efficiency of AMBR in all concentrations of substrate entering the reactor was above 80%. First-order model and Stover-Kincannon were used to investigate the kinetics of COD removal via AMBR biological process; in addition, the two models of Modified Stover-Kincannon and Van der Meer and Heertjes were used to check the kinetic constants of biogas and methane gas production. The results obtained from the models showed that the experimental data on COD removal were more consistent with the results obtained from Stover-Kincannon model (R = 0.999) rather than with the First-order model (R = 0.926). Kinetic constants calculated via Stover-Kincannon model were as follows: saturation value constant (KB) and maximum utilization rate constants (U), respectively, were 208,600 mg/L d and 172,400 mg/L d. We investigated the linear relationship between the experimental data and the values predicted by the models; as compared with the values predicted by the First-order model, the values predicted by Stover-Kincannon model were closer to the values measured via experiments. Based on the results of the evaluation of kinetic coefficients of Stover-Kincannon model, with the migration of the leachate flow from unit 1 to unit 4, U value has fallen significantly. The values of maximum specific biogas production rate (G) and proportionality constant (GB) obtained from the Stover-Kincannon model, respectively, were 35,714 ml/L d and 42.85 (dimensionless) and value of kinetic constant of Van der Meer and Heertjes (ksg) was 0.0473 ml CH/mg COD.
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http://dx.doi.org/10.1016/j.jenvman.2017.10.038DOI Listing
January 2018

Health risk assessment of heavy metal intake due to fish consumption in the Sistan region, Iran.

Environ Monit Assess 2017 Oct 25;189(11):583. Epub 2017 Oct 25.

Department of Environmental Health Engineering, Gonabad University of Medical Sciences, Gonabad, Iran.

The heavy metal (Pb, Cd, Cr, and Ni) content of a fish species consumed by the Sistan population and its associated health risk factors were investigated. The mean concentrations of Pb, Cd, and Cr were slightly higher than the standard levels. The Ni content of fish was below the maximum guideline proposed by the US Food and Drug Administration (USFDA). The average estimated weekly intake was significantly below the provisional tolerable intake based on the FAO and WHO standards for all studied metals. The target hazard quotients (THQ) of all metals were below 1, showing an absence of health hazard for the population of Sistan. The combined target hazard quotient for the considered metals was 26.94 × 10. The cancer risk factor for Pb (1.57 × 10) was below the acceptable lifetime carcinogenic risk (10). The results of this study reveal an almost safe level of Pb, Cd, Cr, and Ni contents in the fish consumed by the Sistan population. Graphical abstract ᅟ.
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http://dx.doi.org/10.1007/s10661-017-6286-7DOI Listing
October 2017

The relationship between environmental exposures and hormonal abnormalities in pregnant women: An epidemiological study in Yazd, Iran.

Women Birth 2018 Jun 27;31(3):e204-e209. Epub 2017 Sep 27.

Department of Clinical Biochemistry, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Electronic address:

Problem: The process of industrialization and lifestyle changes have gradually exposed human ‎societies to a larger number of environmental risk factors, which may cause hormonal ‎abnormalities and congenital anomalies.

Background: The current study aimed to investigate the relationship ‎between environmental factors and hormonal abnormalities among pregnant women in Yazd, ‎Iran.

Methods: A hundred participants were randomly selected from among a group of pregnant women. According to the screening tests (AFP, free β-‎HCG, uE3, PAPP-A, and inhibin-A) performed at the genome clinic in Yazd in 2016, the risk of Down Syndrome (DS) was sufficiently high in this group of pregnant women from which the participants were selected. A ‎questionnaire was used to collect data on the degree of the participants' exposure to pesticides ‎at home, use of canned and fast foods, and consumption of greenhouse fruits. The collected data were ‎analyzed by One-way ANOVA and Kruskal-Wallis Test.

Findings: The mean of Multiple of Median (MoM) for inhibin-A was significantly higher among pregnant ‎women who often or always used pesticides at home (p=0.047). The mean MoM ‎for free β-HCG was significantly higher among pregnant women who often or always used canned ‎foods (p=0.024). Finally, the mean MoM for uE3 (1.85±1.30) was significantly higher among ‎pregnant women who never consumed greenhouse fruits (p=0.003).

Conclusion: It can be concluded that it is possible to reduce environmental exposures affecting hormonal abnormalities among pregnant women by improving nutritional patterns, minimizing the use of pesticides at home, and reducing the intake of canned foods and greenhouse fruits.
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http://dx.doi.org/10.1016/j.wombi.2017.09.002DOI Listing
June 2018

Effect of Organic Loading Rates on biodegradation of linear alkyl benzene sulfonate, oil and grease in greywater by Integrated Fixed-film Activated Sludge (IFAS).

J Environ Manage 2017 May 23;193:312-317. Epub 2017 Feb 23.

Faculty Members of Environmental Science and Technology Research Center, Department of Environmental Health Engineering, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Electronic address:

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.
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http://dx.doi.org/10.1016/j.jenvman.2017.02.038DOI Listing
May 2017

Changes of stress oxidative enzymes in rat mammary tissue, blood and milk after experimental mastitis induced by E. coli lipopolysaccharide.

Vet Res Forum 2015 15;6(2):131-6. Epub 2015 Jun 15.

Department of Pathobiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.

The present study investigated the effects of E. coli lipopolysaccharide (LPS) induced mastitis model in rat on the activity of antioxidant enzyme systems. To achieve this purpose, E. coli LPS were infused into the mammary gland of 12 rats 72 hr postpartum and compared with 12 rats in control group infused intramammary placebo sterile pyrogene - free, physiological saline. The antioxidant activities of the enzymes, superoxide dismutase, glutathione peroxidase, and catalase together with ‎‏malondialdehyde (MDA) level were assayed in blood serum, milk and mammary tissue. Results obtained showed that, the antioxidant enzyme activities in milk, blood serum and mammary tissue were significantly decreased while the level of MDA, the indicator of lipid peroxidation were significantly increased following intramammary inoculation of LPS compared to the control animals. Histopathological examination also revealed the infiltration of inflammatory cells in mammary tissue and disruption of acinar structure and acinar lumina in mastitic rats. The results indicated that E. coli LPS-induced ‎mastitis could alter antioxidant enzymes and increase lipid peroxidation.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4522526PMC
August 2015

Comparing the efficiency of Cyperus alternifolius and Phragmites australis in municipal wastewater treatment by subsurface constructed wetland.

Pak J Biol Sci 2013 Apr;16(8):379-84

Faculty Member, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

Nowadays, application of natural wastewater treatment systems such as wetland not only reduces economic costs and energy consumption, but also decreases environmental pollution. This study aimed to compare efficiency of Cyperus alternifolius and Phragmites australis in Municipal wastewater treatment by Subsurface Constructed Wetland Method. This is an applied-interventionnal study in which three reactors (control pilot, Cyperus alternifolius (umbrella palm) plant pilot and Phragmites australis (reed) plant pilot were designed by subsurface constructed wetland method. Then 90 samples were taken from input and output of reactors with four-day retention time. These samples were tested and finally the data were analyzed by Paired Sample Test statistical analysis. The results showed that removal efficiency of the parameters such as COD, BOD5, TSS, NO3-N, NH3-N, PO4-P, total coliform and fecal coliform was 74, 73, 84, 40, 36, 70, 33 and 38% in Cyperus alternifolius plant wetland, 44, 34, 77, 15, 0.3, 1, 17 and 26% in control wetland and 59, 54, 73, 6, 3, 10, 93 and 50 in Phragmites australis plant wetland, respectively. This reduction rate in all parameters- except fecal coliform- was statistically significant (p = 0.05). The results of this study showed that Cyperus alternifolius plant had higher efficiency in the removal of chemical parameters, whereas Phragmites australis plant had appropriate efficiency in the removal of microbiological parameters. Therefore, it can be concluded that application of these two plants can be effective in wastewater treatment.
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http://dx.doi.org/10.3923/pjbs.2013.379.384DOI Listing
April 2013