Publications by authors named "Mohammad Mehdi Amin"

60 Publications

Enhanced removal of humic acid from aqueous solution by combined alternating current electrocoagulation and sulfate radical.

Environ Pollut 2021 May 10;277:116632. Epub 2021 Feb 10.

Department of Chemistry, Karnatak University, Dharwad, 580 003 India.

Application of alternating current in electrocoagulation and activation of persulfate (AEC-PS) for the effective removal of humic acid (HA) from aqueous solution was evaluated. In order to optimize the removal efficiency HA by the AEC-PS process, several influencing parameters such as pH, reaction time, PS dose, current density (CD), concentration of NaCl, initial concentration of HA, and coexisting cations and anions influence were investigated. From the batch experiments, the highest HA removal efficiency obtained was 99.4 ± 0.5% at pH of 5, reaction time of 25 min, CD of 4.5 mA/cm, PS dose of 200 mg/L, and NaCl concentration of 0.75 g/L for an initial HA concentration of 30 mg/L. When CD increased from 1.25 to 4.5 mA/cm, the HA removal efficiency was improved from 88.8 ± 4.4% to 96.1 ± 1.5%. In addition, the type of coexisting cations and anions exerted a significant role, leading to a reduction in the removal efficiency of HA. To investigate the dominant free activated radical, radical scavengers such as tert-butyl alcohol and ethanol were employed. It was observed that both OH and SO radicals substantially contributed to the removal of HA, and the contribution of SO radical was higher than that of OH radical, suggesting that AEC-PS process could serve as a novel and effective treatment technique for the removal of organic matters from aqueous sources.
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http://dx.doi.org/10.1016/j.envpol.2021.116632DOI Listing
May 2021

Fabrication of activated carbon from pomegranate husk by dual consecutive chemical activation for 4-chlorophenol adsorption.

Environ Sci Pollut Res Int 2021 Mar 17;28(11):13919-13930. Epub 2020 Nov 17.

Institute of Chemistry, Federal University of Rio Grande do Sul (UFRGS), Av. Bento Goncalves 9500, Postal Box 15003, Porto Alegre, RS, 91501-970, Brazil.

In the present work, the fabrication of activated carbon (AC) from pomegranate husk (PHAC) by dual consecutive activation processes with ZnCl and NaOH as a chemical agent was studied. After that, the synthesized PHAC was used for adsorption of 4-chlorophenol (4CP) as a highly toxic compound for the human health and the environment. Different analytical techniques characterized the synthesized PHAC using ZnCl/NaOH. The isotherms of N adsorption and desorption showed that total pore volume (V) and specific surface area (S) of PHAC were 0.404 cm/g and 811.12 m/g, respectively. The 4CP adsorption by PHAC studies revealed that the highest 4CP removal efficiency was 100% and obtained at 50, 100, and 150 mg/L of 4CP concentration with 2.5 g/L of PHAC. Based on the batch experiments, the highest 4CP removal was achieved at pH 6, 2.5 g/L of PHAC, and contact time of 60 min. The 4CP adsorption data of equilibrium and kinetics were successfully fitted to Langmuir's isotherm and Avrami fractional order.
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http://dx.doi.org/10.1007/s11356-020-11624-zDOI Listing
March 2021

Adsorption of 4-chlorophenol by magnetized activated carbon from pomegranate husk using dual stage chemical activation.

Chemosphere 2021 May 15;270:128623. Epub 2020 Oct 15.

Pharmaceutical Engineering, Soniya College of Pharmacy, Dharwad, 580 002, Karnataka, India. Electronic address:

Separation under the influence of magnetic field has been widely explored to tackle environmental issues related to centrifuging and filtration. In this work, activated carbon produced from pomegranate husk (PHAC) using dual stage chemical activation was magnetized with iron salts and used for adsorption of 4-chlorophenol (4CP) from the synthetic wastewater. Adsorption experiments were conducted in batch mode to determine the removal efficiency of magnetized activated carbon pomegranate husk (MPHAC) as a function of initial 4CP concentration, solution pH, MPHAC dose, contact time, ionic strength, and temperature. The rough surface of MPHAC containing pores on the surface had a total pore volume of 0.623 cm/g with a surface area of 1168 m/g. The 4CP adsorption was highly dependent on ionic strength, solution pH, and temperature; the equilibrium was reached in 60 min of contact time. Kinetic models and equilibrium isotherms were employed to assess the fitness of adsorption data; results were fitted best with the Liu model giving maximum adsorption capacities of 446.89 ± 20.75 and 183.64 ± 17.85 mg/g for 1 and 2 g/L of MPHAC, respectively. For the investigation of the adsorption kinetics, Avrami fractionary-order model showed the best fit of the experimental data compared to other kinetic models.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128623DOI Listing
May 2021

Impact of prenatal triclosan exposure on gestational age and anthropometric measures at birth: A systematic review and meta-analysis.

J Res Med Sci 2020 30;25:61. Epub 2020 Jun 30.

Department of Pediatrics, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

Background: Exposure to endocrine disrupting chemicals such as triclosan (TCS) leads to disrupting the endocrine system and consequently effect on the birth outcomes. The findings of studies in this field are controversial.

Materials And Methods: This systematic review and meta analysis was conducted based on the identified published papers in Scopus, Web of Science, and PubMed up to November 2019. All steps, including searching, screening, data extracting, and quality assessment, were done by two independent researchers.

Results: Finally 15 published papers selected. The number of participants in whom the association of TCS exposure was assessed with birth weight, birth length, birth head circumference, and gestational age were 9112, 4311, 2854, and 3181 mother infant pairs, respectively. The pooled analysis showed that TCS exposure during pregnancy leads to increasing the birth weight for boys with β= 3.97 and 95% confidence interval (CI) (-3.98, 11.92), and girls with β= 5.37, 95% CI (-6.00, 16.75), but the association was not statistically significant. In addition, according to fixed effects models, the TCS exposure was not significantly associated with birth length (-0.008, 95% CI [-0.049, 0.034]), birth head circumference (-0.01, 95% CI [-0.08, 0.06]), and gestational age (-0.005, 95% CI [-0.017, 0.006]). Likewise, analysis for data segregated by gender of infants revealed similar results.

Conclusion: The obtained results depicted that the TCS exposure during pregnancy period was associated with higher birth weight for boys and girls. No significant association was observed for TCS exposure with variation of birth length, head circumference, and gestational age duration. In fact, the results showed the evidence of null associations between maternal TCS exposure and birth outcomes.
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http://dx.doi.org/10.4103/jrms.JRMS_918_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7554545PMC
June 2020

The association between familial and environmental factors and prevalence of congenital hypothyroidism in center of Iran.

Environ Sci Pollut Res Int 2021 Feb 15;28(7):8434-8441. Epub 2020 Oct 15.

Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Imam Hossein Children's Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.

The aim of this current study is to investigate the association between familial and environmental factors and prevalence of congenital hypothyroidism (CH) in Isfahan province. In this retrospective cohort study, data of the neonates referred for CH screening in different cities of Isfahan province were evaluated. Data regarding air and soil (lead, cadmium) pollutants were collected. The spatial association between mentioned environmental pollutants and prevalence of CH in different cities of Isfahan province was evaluated by using GIS software, and multilevel linear regression was used for evaluating the levels of environmental pollutants and neonates' serum TSH. During the study period, 389,945 neonates were screened, from which 934 diagnosed with CH (1 in 417 neonates).The prevalence rate of CH was ranged from < 20 in 10,000 live births to > 45 in 10,000 live births in different cities of Isfahan province. There was no any significant association between level of soil lead and cadmium and air pollutants with prevalence of CH in different cities of Isfahan province (P > 0.05).There was a significant positive association between soil cadmium and air pollution evaluated by air quality index (AQI) and level of screening serum TSH in CH patients. Considering the significant association between cadmium and AQI with first serum TSH, it is inferred that the interaction of genetic, autoimmune, familial, and environmental factors with each other could influence on neonatal thyroid function. It seems that the role of some mentioned component is more prominent which should be investigated in future researches.
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http://dx.doi.org/10.1007/s11356-020-10959-xDOI Listing
February 2021

Health risk assessment of potentially toxic elements intake via food crops consumption: Monte Carlo simulation-based probabilistic and heavy metal pollution index.

Environ Sci Pollut Res Int 2021 Jan 25;28(2):1479-1490. Epub 2020 Aug 25.

Faculty of Chemical and Materials Engineering, Shahrood University of Technology, Shahrood, Iran.

The aim of this study is to assess the content of heavy metals and their potential health risk in consumed food crops. To this end, the samples from vegetables, rice, potato, onion, and black tea were derived from high sales and commonly consumed types. The noncarcinogenic health risk of heavy metals to the adults, teens, and children was estimated by target hazard quotients (THQs) and hazard index (HI) calculation. Sensitivity and uncertainty analyses were carried out using Monte Carlo simulations. Heavy metal pollution index (HMI) was used for ranking noncarcinogenic heavy metal pollution in sampled food crops. THQs showed that noncarcinogenic health risks to the local population were largely related to As (0.71 for adults, 0.87 for teens, and 2.4 for children), Mn (0.43 for adults, 0.28 for teens, and 0.64 for children), and Mo (0.12 for adults, 0.02 for teens, and 0.4 for children). HI for individual food crops (HI) in terms of different populations showed that the highest HI was for children while the highest HI was for adults. The arrangement of the calculated HI along with its highest value was in the order of HI (3.71) > HI (0.39) > HI (0.2) > HI (0.13) > HI (0.12) > HI (0.11). The value of HI for all sampled food crops based on their daily ingestion rate achieved by deterministic and probabilistic (Monte Carlo simulations) approaches for adults, teens, and children was 1.63, 1.28, and 1.87, 1.67, 4.51, and 2.48 respectively, and revealed that all populations are vulnerable to the significant noncarcinogenic health risks and children are at more risk. The sensitivity analysis revealed that the ingestion rate (IR) is the most influential factor that contributed to the total risk. The determined HMI showed no heavy metal pollution for all food crops, and rice had higher-order in HMI ranking. These results showed that heavy metals exposure due to food ingestion is a threat to human health and needs choosing a proper strategy to reduce heavy metal exposure.
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http://dx.doi.org/10.1007/s11356-020-10450-7DOI Listing
January 2021

Retention of atenolol from single and binary aqueous solutions by thin film composite nanofiltration membrane: Transport modeling and pore radius estimation.

J Environ Manage 2020 Oct 2;271:111005. Epub 2020 Jul 2.

Pharmaceutical Engineering, Soniya College of Pharmacy, Dharwad, 580 002, Karnataka, India. Electronic address:

The performance of a polyamide-based thin-film composite nanofiltration (NF) membrane (NF33) was investigated for the retention of atenolol, a pharmaceutical pollutant, from the single and binary aqueous solutions. The effect of pH, applied pressure, feed flux, initial atenolol (ATN) concentration, and different co-existing salts with varying concentrations were studied to test the performance of the membrane. The removal efficiency of ATN increased with increasing solution pH giving the highest retention (70.9 ± 3.1) at pH 9, which was slightly decreased with the increasing initial ATN concentration but increased with increasing applied pressure and feed flux. As per the uncharged solutes rejection concept, the average pore radius of NF membrane for slit-like and cylindrical pore geometries were, respectively 0.169 ± 0.003 and 0.264 ± 0.009 nm. The Spiegler-Kedem model could predict the performance of NF membrane by retaining ATN over the investigated range of feed flux. The calculated reflection coefficient (σ) was close to unity, demonstrating the convective transport. Addition of CaCl as a co-existing salt into the feed showed promoting effect on ATN retention, and its efficiency was lowered by the addition of NaCl and NaSO salts. As per the cost analysis, the total annualized cost of treatment by the NF was found to be 0.53 $/m.
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http://dx.doi.org/10.1016/j.jenvman.2020.111005DOI Listing
October 2020

Air pollution and hospitalization: an autoregressive distributed lag (ARDL) approach.

Environ Sci Pollut Res Int 2020 Aug 29;27(24):30673-30680. Epub 2020 May 29.

Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

Air pollution is one of the biggest global environmental problems in urban regions. This study aimed to investigate the validity of the relationship between air pollution and respiratory and cardiovascular hospitalization using time series methods. This time series study was conducted in Isfahan, Iran. We used data of hospitalized cases in three main university hospitals (Alzahra, Noor, Chamran) and air pollution data from 2014 to 2016. We applied the autoregressive distributed lag (ARDL) bounds testing approach of cointegration to examine the relationship between the air pollution and hospitalizations of respiratory and cardiovascular diseases. The results of air quality assessment on the number of respiratory and cardiovascular hospitalization demonstrate that in the case of cardiovascular disease, both in the long run and in the short run, the air quality index has a significant impact on men and women with a bigger impact in the long run compared to the short run. The value of the long-run coefficient indicates the relationship between air pollution index and cardiovascular hospitalization is stronger than respiratory hospitalizations. In the long term, the effect of the air quality index (AQI) on the number of hospitalizations is more than that in the short term. Based on the results, a 10-unit increase in AQI leads to 5.3% increase in the number of respiratory hospitalization. Accordingly, a 10-unit increase in AQI will result in 7.3% increase in the number of cardiovascular hospitalizations.
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http://dx.doi.org/10.1007/s11356-020-09152-xDOI Listing
August 2020

Synergistic degradation of 4-chlorophenol by persulfate and oxalic acid mixture with heterogeneous Fenton like system for wastewater treatment: Adaptive neuro-fuzzy inference systems modeling.

J Environ Manage 2020 Aug 14;268:110678. Epub 2020 May 14.

Pharmaceutical Engineering, SET's of Pharmacy, Dharwad, 580 002, Karnataka, India. Electronic address:

The 4-chlorophenol (4-CP) is known to be a highly toxic compound having harmful effects on human health and the environment. Due to adverse effect of 4-CP, a new combination of persulfate (PS) and oxalic acid (OA) with heterogeneous Fenton like (HFL) system was developed and applied for 4-CP degradation as an emerging contaminant from synthetic wastewater. The individual (OA, PS, and HFL) and combined (HFL/OA, HFL/PS, and HFL/OA/PS) systems were investigated under various conditions to synergistic effects verification and determination of degradation mechanism of 4-CP. Compared to individual and combined systems, significant synergetic of 4-CP degradation efficiency was observed by HFL/OA/PS system. The highest 4-CP degradation efficiency by HFL/OA/PS system under optimal conditions (solution pH: 6, HO dose: 275 mg/L, goethite dose: 125 mg/L, OA dose: 50 mg/L and PS dose: 100 mg/L) with an initial 4-CP concentration of 30 mg/L was 99.6 ± 4.9% after 35 min reaction time. 4-CP degradation by HFL/OA/PS system was followed with the first-order kinetic. The application of radical scavengers including ethanol (EtOH) and tert-butyl alcohol (TBA) revealed that the SO radical was determined as primary produced radical species. The Cl- ions release was measured during degradation reaction at various 4-CP concentrations and indicating the complete 4-CP degradation. The developing of the adaptive neuro-fuzzy inference system (ANFIS) for 4-CP degradation efficiency prediction was revealed. These results show that prediction of 4-CP degradation efficiency using HFL/OA/PS system is possible by the ANFIS model with a high accuracy (R: 0.98).
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http://dx.doi.org/10.1016/j.jenvman.2020.110678DOI Listing
August 2020

Evaluation of toxic effects of platinum-based antineoplastic drugs (cisplatin, carboplatin and oxaliplatin) on green alga Chlorella vulgaris.

Aquat Toxicol 2020 Jun 24;223:105495. Epub 2020 Apr 24.

Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address:

Platinum-based antineoplastic drugs (PBADs) enter the environment via hospital and municipal wastes as reactive and highly toxic molecules. Chlorella vulgaris is a freshwater microalgae and is used as an excellent aquatic model for toxicity assessment. In the present study, the toxicity of PBADs to C. vulgaris was investigated for better understanding of PBADs environmental toxicity. The algae were cultured in Bold´s Basal Medium (BBM) and exposed to different concentrations of PBADs for 48, 72 and 96 h. Then, cell proliferation, the synthesis of photosynthetic pigments, protein content, malondialdehyde (MDA) release and antioxidant potential were determined. IC s of cisplatin, carboplatin and oxaliplatin for 96 h of exposure were 106.2, 124.3 and 153.9 mg/L respectively. Cell proliferation, synthesis of chlorophyll a, chlorophyll b and algal protein content significantly decreased in a time and dose-dependent manner. The release of MDA to culture media significantly increased and antioxidant potential decreased. Cisplatin showed more toxic effects on C. vulgaris compared to carboplatin and oxaliplatin indicating its severe toxicity for marine organisms. PBADs induce their toxic effects in algal cells via the interaction with DNA, production of free radicals (such as reactive oxygen species), lipid peroxidation and cell wall damages. Due to these toxic effects of PBADs for various environmental organisms, there must be severe restriction on their release into the environment.
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http://dx.doi.org/10.1016/j.aquatox.2020.105495DOI Listing
June 2020

Influence of co-existing cations and anions on removal of direct red 89 dye from synthetic wastewater by hydrodynamic cavitation process: An empirical modeling.

Ultrason Sonochem 2020 Oct 18;67:105133. Epub 2020 Apr 18.

Division of Sustainable Development, College of Science and Engineering, Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, Qatar.

In the present study the evaluation of Direct Red 89 (DR89) dye removal from synthetic wastewater by a lab-scale hydrodynamic cavitation (HC) process has been investigated under different operational conditions; the influence of co-existing cations and anions was applied using synthetic wastewater to assess whether the DR89 removal was enhanced. To study the effect of operational parameters, an empirical approach was adopted for the modeling of the HC process. The results showed that the DR89 degradation rate was strongly influenced by solution pH, reaction time and initial DR89 concentration. The removal efficiencies of DR89 were enhanced remarkably with the reaction time increment. When the initial concentration of DR89 increased from 30 to 90 mg/L, the DR89 removal efficiency decreased from 36.3 ± 3.8% to 17.5 ± 2.5%. In addition, the highest DR89 removal efficiency (75.4 ± 3.4%) was observed at a solution pH of 3. At a solution pH of 8, the DR89 removal efficiency was 18.4 ± 1.1%. An initial DR89 concentration of 80 mg/L was 75.4 ± 5.1% degraded after 130 min at a solution pH of 3. The results indicated that a synergistic effect occurred due to the added ions except for HCO. The removal of DR89 by the HC process was extremely enhanced with NO‾ ions with synergetic index higher than 2.5. Kinetic studies revealed that the decolorization of DR89 by HC followed a first order kinetic mechanism. The comparison between the predicted results of the empirical model and experimental data was also conducted. The empirical model described the DR89 removal efficiency under different conditions (R: 0.93) and the results showed the HC reaction to be a useful technology for the treatment of dye in the textile wastewater.
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http://dx.doi.org/10.1016/j.ultsonch.2020.105133DOI Listing
October 2020

Omega 3 Supplementation Can Regulate Inflammatory States in Gas Station Workers: A Double-Blind Placebo-Controlled Clinical Trial.

J Interferon Cytokine Res 2020 05 13;40(5):262-267. Epub 2020 Mar 13.

Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

Environmental exposure to diesel particulate matter and commercial gasoline in gas station workers might induce oxidative stress and changes in the balance of the immune system. In this study, the immunomodulatory impacts of omega 3 fatty acid (ω3FA) supplement were assessed on inflammatory and anti-inflammatory markers in gas station workers in a double-blind placebo-controlled clinical trial. Fifty-three men working in gas stations were treated with ω3FA ( = 29) or placebo ( = 24) for 60 days. C-reactive protein, interleukin-12 (IL-12), transforming growth factor β (TGF-β), interferon γ (IFN-γ), tumor necrosis factor α, IL-10, and IL-17 levels were measured by enzyme-linked immunosorbent assay method before and after the completion of the trial. The concentrations of IFN-γ and IL-17 were significantly decreased in ω3FA group compared with the placebo group ( < 0.001). Moreover, the levels of inhibitory cytokines including TGF-β and IL-10 significantly were increased in ω3FA group ( < 0.001). Overall, ω3FA nutritional supplementation can be useful in reducing inflammatory immune responses and maintaining immune tolerance in people with high exposure to inflammation-inducing factors. [Figure: see text].
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http://dx.doi.org/10.1089/jir.2019.0220DOI Listing
May 2020

Paraben Content in Adjacent Normal-malignant Breast Tissues from Women with Breast Cancer.

Biomed Environ Sci 2019 12;32(12):893-904

Department of Biostatistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.

Objective: Accumulation of estrogenic compounds and other carcinogens in normal breast tissues contributes to unpredictable breast cancer incidence during adolescence and throughout life. To assess the role of parabens in this phenomenon, the paraben content of adjacent normal-malignant breast tissues is measured in women with breast cancer living in Isfahan Province, Iran.

Methods: Adjacent normal-malignant breast tissue samples were obtained from 53 subjects. The parabens including methyl-paraben (MePB), ethyl-paraben (EtPB), propyl-paraben (PrPB), and butylparaben (BuPB) were extracted from the sample supernatant and then subjected to gas chromatography analysis.

Results: Some risk factors for breast cancer were stimulated by parabens in adjacent malignant-normal breast tissues among young and middle-aged women with breast cancer. We observed a significant association for dose-response pattern of MePB [OR = 98.34 (11.43-185.2), P = 0.027] for both ER+ and PR+ women and MePB [OR = 164.3 (CI: 112.3-216.3), P < 0.001] for HER2+ women than women with negative receptors. The risk of 95-fold increase in MePB dose and 164-fold increase in ΣPBs dose were significant for women with hereditary breast cancer in first-degree relatives.

Conclusion: These results may promote future epidemiology studies and strategies to improve women's lifestyle and consume paraben-free products.
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http://dx.doi.org/10.3967/bes2019.112DOI Listing
December 2019

In situ treatment of metalworking wastewater by chemical addition-dissolved air flotation coupled with UV, HO & ZnO.

Heliyon 2020 Jan 26;6(1):e03091. Epub 2019 Dec 26.

Department of Environmental Health Engineering, School of Public Health, Shahid Beheshti University of Medical Science, Tehran, Iran.

The hybrid treatment techniques have been proven that could be a proper solution to the metalworking fluid (MWF) wastewaters disposal challenge. Hence, this investigation was conducted aim to the assessment of chemical addition-dissolved air floatation (CA-DAF) unit followed with a heterogeneous photocatalytic (PC) process as UV/HO/ZnO to treat MWF wastewater produced in one of the central industrial estates in the Middle East. The CA-DAF unit was implemented as trial and errors and had an appropriate efficiency. However, the environmental discharge standards were not achieved only by this unit, so that, a PC process considered for this purpose in a pilot-scale reactor. And also, Chemical oxygen demand (COD), total petroleum hydrocarbons (TPHs) were considered as physicochemical parameters to analyze the applied photochemical reaction throughout the concentrations of ZnO and HO, and pH value as variables of the study. The ideal and optimized conditions were observed at pH 10, 600 mg l of ZnO, and 13.11 g l of HO via 99.87% and 97.9% reduction rates in total COD and TPH, respectively. These removal rates were obtained for this integrated strategy under the optimized reaction. By evaluating the synergistic effect, it was found that UV/ZnO could be a predominant reaction in this process. The organic and intermediates analysis appeared 78.46% reduction for all detected organic matters. Besides, PC generation of bis phthalate, mono phthalate, benzene, and benzoic acid to 2,6-bis (1,1-dimethylethyl)-4-mthyl phenol was the reason of the residual phenolic compound concentration in the reaction solution with low removal rate. The kinetic study showed that this reaction could be well fitted with the pseudo-first-order kinetic model by equal with 0.973 and 0.988 in turn for COD and TPH. The expenditures to treat 1 m of the CA-DAF was estimated at 5.335 us$ via cost analysis. Finally, the collected findings indicate that CA-DAF integrated with UV/HO/ZnO can be an efficient approach in the MWF wastes disposal or treatment for reuse.
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http://dx.doi.org/10.1016/j.heliyon.2019.e03091DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6938887PMC
January 2020

Human papilloma virus (HPV) genotypes concordance between Iranian couples referrals.

Infect Agent Cancer 2019 9;14:22. Epub 2019 Sep 9.

4Research Center for Clinical Virology, Tehran University of Medical Sciences, Tehran, Iran.

Background: Human Papilloma Virus (HPV) genotypes concordance among sexual couples has been evaluated in many investigations with considerable variations in the concordance. However, no such study has carried out between Iranian couples yet

Methods: Urogenital specimen from both males and females of couples were taken and transferred to Nilou laboratory for molecular analysis. HPV DNA extraction and typing were carried out using cobas 4800 platform. Demographic and virological data were analyzed afterwards.

Results: One hundred fourteen couples were enrolled in the study. The mean age of participants were 36 ± 8 and 32 ± 7 for males and females, respectively. 64 (28%) of specimens were positive for at least one HPV genotype. The positive rates within genders were 30.7 and 25.4% for females and males, respectively with a considerable association ( value 0.021). Within the positive samples, 13(5.7%), 8 (7%) and 31(13.5%) were belonged to 16, 18 and other HR genotypes. 59 (51.8%) couples who were negative for HPV showed negative concordance. Of the total positive HPV patients (55 couples, 48.2%), 9 (16.3%) couples had positive concordance and the rest of 46 (83.7%) couples (either of spouse being negative and the other being positive for HPV) showed neither kinds of concordance.

Conclusion: Recognition of the dynamics of HPV infection not only in women, but in their sexual partners could impact the implementation of preventive measures like HPV vaccination for cervical cancer and other HPV-related diseases for both sexual partners.
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http://dx.doi.org/10.1186/s13027-019-0241-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6734344PMC
September 2019

Electron flow of biological H production by sludge under simple thermal treatment: Kinetic study.

J Environ Manage 2019 Nov 6;250:109461. Epub 2019 Sep 6.

Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran; Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address:

Mixed culture sludge has been widely used as a microbial consortium for biohydrogen production. Simple thermal treatment of sludge is usually required in order to eliminate any H-consuming bacteria that would reduce H production. In this study, thermal treatment of sludge was carried out at various temperatures. Electron flow model was then applied in order to assess community structure in the sludge upon thermal treatment for biohydrogen production. Results show that the dominant electron sink was acetate (150-217 e- meq/mol glucose). The electron equivalent (e- eq) balances were within 0.8-18% for all experiments. Treatment at 100 °C attained the highest H yield of 3.44 mol H/mol glucose from the stoichiometric reaction. As the treatment temperature increased from 80 to 100 °C, the computed acetyl-CoA and reduced form of ferredoxin (Fd) concentrations increased from 13.01 to 17.34 e- eq (1.63-2.17 mol) and 1.34 to 4.18 e- eq (0.67-2.09 mol), respectively. The NADH balance error varied from 3 to 10% and the term e-(Fd↔NADH) (m) in the NADH balance was NADH consumption (m = -1). The H production was mainly via the Fd:hydrogenase system and this is supported with a good NADH balance. Using the modified Gompertz model, the highest maximum H production potential was 1194 mL whereas the maximum rate of H production was 357 mL/h recorded at 100 °C of treatment.
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http://dx.doi.org/10.1016/j.jenvman.2019.109461DOI Listing
November 2019

Efficient methane production from petrochemical wastewater in a single membrane-less microbial electrolysis cell: the effect of the operational parameters in batch and continuous mode on bioenergy recovery.

J Environ Health Sci Eng 2019 Jun 6;17(1):305-317. Epub 2019 Feb 6.

3Department of Pharmaceutical Biotechnology, Shiraz University of Medical Sciences, Shiraz, Iran.

The main objective of this study is to evaluate the treatment and simultaneous production of methane from low-strength petrochemical wastewater by single membrane-less microbial electrolysis cells. To achieve this objective, the influence of variables such as applied voltage, operation mode, and hydraulic retention time (HRT) on the performance of the MEC system was investigated over a period of 110 days. According to the obtained results, the maximum COD removal efficiency in the batch mode was higher than which in the continuous mode (i.e. 85.9% vs 75.3%). However, the maximum methane production in the continuous mode was almost 1.6 times higher than which in the batch mode. The results show, COD removal, methane content, and methane production in both operation modes, were enhanced as applied voltage increased from 0.6 to 0.8-1 V. The proportion of methane, methane production rate, and COD removal were increased as HRT decreased from 72 to 48 h, while these values were decreased as the HRT decreased from 48 to 12 h. In continues mode, the energy efficiency had a range of 94.7% to 97.9% with an average of 96.6% in phase III, which almost recovered all of the electrical energy input into the system. These results suggest that single membrane-less microbial electrolysis cell is a promising process in order to the treatment of low-strength wastewater and methane production.
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http://dx.doi.org/10.1007/s40201-019-00349-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582024PMC
June 2019

Biohydrogen production from alkaline wastewater: The stoichiometric reactions, modeling, and electron equivalent.

MethodsX 2019 20;6:1496-1505. Epub 2019 Jun 20.

Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

Hydrogen gas (H) is the cleanest energy carrier with 142 kJ/g energy content and without toxic byproducts release during combustion. There is interest to H production by biological process from sustainable resources including municipal and industrial wastewater and also solid waste. Here, we describe the biohydrogen production that involves first survey the effect of alkalinity on biohydrogen production based on stoichiometric reaction, followed by the electron equivalent balances determination and examination of prediction capability of Gamperts model for biohydrogen production. •The method uses a dark fermentation biological process for H production from wastewater.•As the influent alkalinity increased, the hydrogen production increased and then promptly descended.•The predicted gas volume, based on Gamperts model confirmed good agreement with experimental value.
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http://dx.doi.org/10.1016/j.mex.2019.06.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6603300PMC
June 2019

Atenolol adsorption onto multi-walled carbon nanotubes modified by NaOCl and ultrasonic treatment; kinetic, isotherm, thermodynamic, and artificial neural network modeling.

J Environ Health Sci Eng 2019 Jun 6;17(1):281-293. Epub 2019 Feb 6.

6Deputy of Health, Hamadan University of Medical Sciences, Hamadan, Iran.

The removal of pharmaceutical pollutants from the aqueous environment is a great environmental concern, mainly due to their diversity, high consumption, and sustainability. In the current study, we aimed to investigate the ability of multi-walled carbon nanotubes (MWCNTs) modified by sodium hypochlorite (NaOCl) and ultrasonic treatment in refining wastewaters contaminated with Atenolol β-blocker drug (ATN). The physical and structural characteristics of the raw MWCNTs and modified MWCNTs (M-MWCNTs) were analyzed using SEM, TEM, Raman spectroscopy, TGA, and FT-IR techniques. The effects of different parameters, including pH, initial concentration, contact time, and temperature were studied and optimized. Subsequently, the adsorption data were analyzed by several kinetic and equilibrium isotherm equations and modeled by artificial neural network (ANN). Highest ATN removal (87.89%) ((q = 46.03 mg g)) occurred on the adsorbent activated within 10 s of ultrasonication time and NaOCl 30%. Moreover, adsorbent modification significantly improved the ATN removal, so that the removal rate on the raw MWCNTs was about 58%, but in the same conditions, M-MWCNTs removed more than 92% of the adsorbate. The adsorption process reached equilibrium after 90 min under the optimized pH of 6. According to ANN modeling, approximately the whole values dispersed around the 45°line, indicating a good compatibility between the trial results and ANN-predicted data. The modification of MWCNTs in proper ultrasonic power via appropriate concentration of NaOCl solution removed many of the impurities and significantly improved the adsorption performance of MWCNTs.
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http://dx.doi.org/10.1007/s40201-019-00347-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582043PMC
June 2019

Degradation of UV-filter Benzophenon-3 in aqueous solution using TiO coated on quartz tubes.

J Environ Health Sci Eng 2018 Dec 15;16(2):213-228. Epub 2018 Aug 15.

4Department of Fisheries, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran.

Background: Benzophenone-3 (BP-3), one of the emerging pollutants, is commercially synthesized as UV filter used in cosmetics and other personal care products and its occurrence in the aquatic environment has widely been reported. The goal of this study was to enhance an AOP method for degradation of UV filter Benzophenone-3 in aqueous solutions

Method: In this study, sol-gel method was applied to synthesis TiO nanoparticles. Subsequently, the nanoparticles were successfully coated on quartz tubes. The synthesized catalyst was characterized using XRD, FE-SEM and EDX analysis. Then, the efficiency of photocatalytic process using TiO coated quartz tubes for BP-3 degradation from synthetic and real aqueous solution was assessed.

Result: The optimum contact time and solution pH for the highest BP-3 degradation in the synthetic solution were found at 15 min and 10, respectively. The maximum degradation (98%) of BP-3 by photocatalytic process was observed at 1 mg/L initial BP-3 concentration using 225 cm of catalyst surface area. Among the three applied kinetic models, the experimental data were found to follow the first-order equation more closely with the rate constant of 0.2, 0.048 and 0.035 1/min for 1, 3 and 5 mg/L of initial BP-3 concentration, respectively. In order to investigate the potential of this process for real effluent, the treatment of swimming pool water and wastewater treatment plant was examined and BP-3 degradation close to 88% and 32.1 was achieved, respectively.

Conclusion: Based on the obtained data, the photocatalytic process could successfully be applied for water treatment in swimming pools and other effluent containing BP-3 with low turbidity. The advantage of this study is that the synthesized catalyst can be used repeatedly needless to remove catalyst from the treated solution. In addition, AOP can effectively eliminate organic compounds in aqueous phase, rather than transferring pollutants into another phase. The limitation of this study is that in solution with high turbidity photocatalytic degradation can be hampered and pre- treatment is needed to reduce turbidity.
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http://dx.doi.org/10.1007/s40201-018-0309-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277332PMC
December 2018

Biohydrogen production under hyper salinity stress by an anaerobic sequencing batch reactor with mixed culture.

J Environ Health Sci Eng 2018 Dec 1;16(2):159-170. Epub 2018 Nov 1.

4Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands.

Background: This study investigated the effect of organic loading rate (OLR) and NaCl concentration on biohydrogen production by preheated anaerobic sludge in a lab scale anaerobic sequencing batch reactor (ASBR) fed with glucose during long time operation.

Methods: During ASBR operation, the OLR was increased in steps from 0.5 to 5 g glucose/L.d and NaCl addition started at an OLR of 5 g glucose/L.d, to obtain NaCl concentrations in the reactor in the range of 0.5-30 g/L.

Results: With an increasing OLR from 0.5 to 5 g glucose/L.d, the biohydrogen yield increased and reached 0.8 ± 0.4 mol H/mol glucose at an OLR of 5 g glucose/L.d. A NaCl concentration of 0.5 g/L resulted in a higher yield of biohydrogen (1.1 ± 0.2 mol H/mol glucose). Concentrations above 0.5 g/L NaCl led to decreasing biohydrogen yield and the lowest yield (0.3 ± 0.1 mol H/mol glucose) was obtained at 30 g/L of NaCl. The mass balance errors for C, H, and O in all constructed stoichiometric reactions were below 5%.

Conclusions: The modified Monod model indicated that r (H2)max and Ccrit values were 23.3 mL H2/g VSS/h and 119.9 g/L, respectively. Additionally, ASBR operation at high concentrations of NaCl shifted the metabolic pathway from acidogenic toward solventogenic.
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http://dx.doi.org/10.1007/s40201-018-0304-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277343PMC
December 2018

Association of benzene exposure with insulin resistance, SOD, and MDA as markers of oxidative stress in children and adolescents.

Environ Sci Pollut Res Int 2018 Dec 3;25(34):34046-34052. Epub 2018 Oct 3.

Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

Benzene is a ubiquitous environmental pollutant with various health effects. It is reported that benzene exposure might be associated with insulin resistance in elderly adults. The aim of this study is to investigate the association between urinary benzene metabolite, trans, trans-muconic acid (t,t-ma) and markers of oxidative stress and insulin resistance in children and adolescents. This cross-sectional study was conducted in 2017 among 86 children and adolescents, aged 6-18 years, living in Isfahan, Iran. t,t-ma was measured as urinary benzene metabolite and homeostasis model assessment (HOMA-IR) was determined as an index of insulin resistance. Moreover, malondialdehyde (MDA) and superoxide dismutase (SOD) were assessed as oxidative stress markers. We found significant association between insulin resistance, fasting blood glucose, and fasting blood insulin with t,t-ma (p values = 0.002, 0.03, and 0.001, respectively). Results of this study indicate that benzene metabolite in higher concentrations in comparison with lower concentrations is associated with increased risk of insulin resistance. Moreover, after adjustment for age, sex, and household passive smoking, statistically significant increase were documented in SOD and MDA (4.49- and 3.54-fold, respectively) in intermediate levels of t,t-ma vs. low levels of t,t-ma (p values = 0.01 and 0.034, respectively). To the best of our knowledge, this is the first study in its kind in the pediatric age group. It showed that benzene exposures, even in environmental levels, might be associated with insulin resistance and oxidative stress in children and adolescents. Further longitudinal studies are necessary to assess the clinical impacts of this finding.
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http://dx.doi.org/10.1007/s11356-018-3354-7DOI Listing
December 2018

Data on biosurfactant assisted removal of TNT from contaminated soil.

Data Brief 2018 Aug 22;19:1600-1604. Epub 2018 Jun 22.

Department of Environmental Health Engineering, School of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Contamination of environment, especially soil, is in great concern and can cause health problems. Thus, remediation of these pollutants through environmentally friendly methods should be considered. The aim of this data was bioremediation of TNT from contaminated soil. Two plastic pans were used as bioreactor. In each pan, 3 kg of soil was used. Concentration of TNT in contaminated soil was 1000 mg/kg. Rhamnolipid in concentration of 60 mg/l was added to intended pan. Sampling was done in each two weeks. In order to assessment of TNT degradation, samples were analyzed with HPLC. The data showed that after 154 days of experiment, TNT removal in soil that amended with rhamnolipid was 73% and in experiment with no addition of rhamnolipid was 58%. Based on the obtained data rhamnolipid was effective in remediation of TNT contaminated soil.
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http://dx.doi.org/10.1016/j.dib.2018.06.040DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6141866PMC
August 2018

Association of exposure to Bisphenol A with obesity and cardiometabolic risk factors in children and adolescents.

Int J Environ Health Res 2019 Feb 11;29(1):94-106. Epub 2018 Sep 11.

f Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease , Isfahan University of Medical Sciences , Isfahan , Iran.

In this study, the association of exposure to Bisphenol A (BPA) with obesity and cardiometabolic risk factors was investigated on 132 children and adolescents aged 6-18 years living in Isfahan, Iran. Potential contributors to BPA exposure were assessed by a questionnaire. Total BPA was detected in urine samples of all participants without significant difference in boys and girls. The mean body mass index (BMI) and waist circumference (WC) increased significantly across the BPA tertiles (p for trend = < 0.001). Similar trend was documented for systolic blood pressure (SBP) and diastolic blood pressure (DBP) as well as fasting blood sugar. The risk of obesity was 12.48 times higher in participants in the third tertile of BPA than in others (95% CI: 3.36-46.39, p < 0.001). The current study showed significant association between BPA exposure with obesity and some cardiometabolic risk factors in children and adolescents, however, further longitudinal studies are necessary to evaluate the clinical effects of this finding. Abbreviations: BMI: Body Mass Index; BPA: Bisphenol A; BSTFA: N, O-Bistrifluoroacetamide; CDC: Centers for Disease Control and Prevention; CI: Circumference Interval; DBP: Diastolic Blood Pressure; DLLME: Dispersive liquid-liquid microextraction method; FBS: Fasting Blood Glucose; HDL: high-density lipoprotein cholesterol were; LDL: low-density lipoprotein cholesterol; OR: Odd Ratio; PA: Physical Activity; SBP: Systolic Blood Pressure; TC: total cholesterol; TG: triglycerides; WC: Waist Circumference.
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http://dx.doi.org/10.1080/09603123.2018.1515896DOI Listing
February 2019

Association of urinary concentrations of phthalate metabolites with cardiometabolic risk factors and obesity in children and adolescents.

Chemosphere 2018 Nov 31;211:547-556. Epub 2018 Jul 31.

Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.

This study aimed to investigate the association of urinary concentration of phthalate metabolites with obesity and cardiometabolic risk factors in a pediatric population. This study was conducted in 2016 on 242 children and adolescents, aged 6-18 years, living in Isfahan, Iran. Urinary concentration of mono-butyl phthalate (MBP), mono-benzyl phthalate (MBzP), Mono-2-ethylhexyl phthalate (MEHP), Mono-methyl phthalate (MMP), Mono (2-ethyl-5-exohexyl) phthalate (MEOHP), and mono (2-ethyl-5hydroxyhexyl) phthalate (MEHHP) metabolites were determined. The association of these metabolites with obesity and cardiometabolic risk factors was examined using student t-test, linear and logistics regression tests. Of the 242 participants studied, 140 (57.9%) were girls and 102 (42.1%) were boys. The mean (SD) age of the population was 11.34 (2.55) years and no significant difference existed in terms of age (p-value = 0.374). MBzP, MBP, MMP were observed in urine samples of all subjects, and MEHP, MEOHP, and MEHHP were observed in 99.6, 95.87, and 96.28% of the subjects, respectively. Of the total participants, 15.2% (n = 37) were obese and 37.7% (n = 92) were overweight. According to the logistic regression analysis, except MEOHP, all other pollutants were significantly associated with obesity (OR >1, p-value ≤ 0.002). A significant association existed between MBP and elevated blood pressure [OR in tertile3 = 4.87 (CI: 1.02-23.32), p-value = 0.024]. MBzP and MEHP were significantly associated with obesity, elevated levels of triglyceride and blood pressure. Increase in MBzP metabolite in the 3rd tertile resulted to about 2.5-fold increase in triglyceride levels than the first tertile [OR  = 2.7 (CI: 1.23-6.22)]. The findings of this study clearly showed the association between phthalate metabolites with obesity, cardiometabolic risk factors in children and adolescents, however further longitudinal studies are necessary to evaluate the clinical effects of this finding.
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http://dx.doi.org/10.1016/j.chemosphere.2018.07.172DOI Listing
November 2018

Removal of atenolol from aqueous solutions by multiwalled carbon nanotubes modified with ozone: kinetic and equilibrium study.

Water Sci Technol 2018 Jul;2017(3):636-649

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

The aim of study is removal of atenolol from aqueous solutions by multiwalled carbon nanotubes modified with ozone. The design of the experiment was adopted across four levels with the L16 matrix arrangement. The factors influencing atenolol adsorption include changes in the pH value, contact time, the dose of the modified multiwall carbon nanotube, and the initial concentration of atenolol in the solution; these factors were evaluated along with the extent of their influence on removal efficiency. Data analyses were performed by the Design Expert 6 software. The results indicated that the pH, contact time, adsorbent dose, and the initial concentration were 7, 20 min, 0.15 g/L and 1 mg/L, respectively. In this state, the removal efficiency was calculated to be 75.79%. The maximum adsorption capacity was obtained as 5.05 mg/g under optimal conditions. The data were analyzed using adsorption models obtained from the isotherm fitting tool software. The results suggested that the data had a greater congruence with the Freundlich model (corrected Akaike information criterion = 2.58). Furthermore, the kinetics of the reactions followed pseudo second order kinetics (R = 0.95). Based on this study, it can be concluded that modified multiwall carbon nanotubes enjoy high potential and efficiency as adsorbents for the removal of atenolol from aqueous solutions.
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http://dx.doi.org/10.2166/wst.2018.105DOI Listing
July 2018

Biohydrogen Production as Clean Fuel from physically Pretreated Mixed Culture.

Adv Biomed Res 2018 23;7:80. Epub 2018 May 23.

Department of Environmental Health Engineering, Student Research Committee, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.

Background: Due to depletion of fossil fuel reserves, global warming, and the need for energy efficiency, the new energy resource is required. For this purpose, hydrogen can be considered as clean and efficient energy carrier. In this study, biohydrogen production from physical pretreated mixed culture was investigated.

Materials And Methods: In this study, the optimal conditions for physical pretreatment of mixed culture were investigated for the enrichment of hydrogen-producing bacteria (HPB). Three individual pretreatment processes, including thermal, ultraviolet (UV) radiation, and ultrasonication (US) were conducted in batch tests. The batch tests were carried out via 500 mL glass flasks with working volume 400 mL. Glucose was used as sole substrate, and other essential nutrient and trace elements were added. To agitation of substrate with HPB inoculum, the magnet stirrer was used at 60 rpm.

Results: The results showed the production of H gas could be increased by appropriate pretreatment methods including thermal pretreatment at 100°C. At 100°C as a pretreatment, the volume of H gas was 112.25 mL and followed by US (97.46 mL), UV (89.11 mL), 80°C (72.72 mL), 90°C (53.95 mL), and 70°C (26.01 mL). In the pretreatment methods, the solution pH and effluent soluble chemical oxygen demand was 6.3-6.7 and 5100-8300 mg/L, respectively.

Conclusions: The Gompertz model depicts that all values were more than 0.93, indicating that the fitted curves were best fitted with the experimental points.
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http://dx.doi.org/10.4103/2277-9175.233030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5991287PMC
May 2018

Comparison of Acetate-butyrate and Acetate-ethanol Metabolic Pathway in Biohydrogen Production.

J Med Signals Sens 2018 Apr-Jun;8(2):101-107

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

Background: Hydrogen gas is the cleanest energy carrier and could be produced by biological process. Dark fermentation is one of the biohydrogen production methods that carried out just on organic wastes conversion.

Methods: In this study, the batch tests were conducted to compare the biohydrogen production and glucose fermentation via acetate-butyrate and acetate-ethanol metabolic pathway induced by NaOH and KOH (10 M) pretreatment. In batch test, the glucose concentration in the feed was varied from 3.75 to 15 g/L under mesophilic conditions (37°C ± 1°C). In order to sludge pretreatment, NaOH and KOH (as an alkaline agent) was used.

Results: Batch tests showed that maximum biohydrogen production under NaOH (2.7 ± 0.5 L) and KOH (2.2 ± 0.7 L) pretreatment was achieved at 15 g/L of influent glucose. In the batch test, with increasing influent glucose concentration, the lower yields of hydrogen were observed. The biohydrogen reactions had good electron closure (5.2%-13.5%) for various glucose concentrations and pretreatments. For NaOH and KOH pretreatment, the biohydrogen yield decreased from 2.49 to 1.63 and from 2.22 to 1.2 mol H/mol glucose, respectively, when glucose concentration increased from 3.75 to 15 g/L.

Conclusions: By applying alkaline sludge pretreatment by NaOH and KOH, the glucose fermentation was followed with acetate-butyrate and acetate-ethanol metabolic pathway, respectively. The lower biohydrogen yields were observed under acetate-ethanol metabolic pathway and related to metabolically unfavorable for biohydrogen production.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5992901PMC
June 2018

Association of polycyclic aromatic hydrocarbons with cardiometabolic risk factors and obesity in children.

Environ Int 2018 09 7;118:203-210. Epub 2018 Jun 7.

Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address:

A limited body of evidence exists on the association of exposure to polycyclic aromatic hydrocarbons (PAHs) with cardiometabolic risk factors and obesity in children. No study has evaluated these associations in subgroups of children with and without excess weight, and those with and without cardiometabolic risk factors. We aimed to investigate the association between PAH exposure and cardiometabolic risk factors in children independent of their weight status. The secondary aim was to evaluate the obesogen properties of PAHs in children independent of their cardiometabolic risk factors. This study was based on a representative sample of 186 children (aged 6-18 years) living in Isfahan, Iran (2014-2016). We enrolled four groups of participants with and without excess weight and with and without cardiometabolic risk factor. Urinary levels of monohydroxy PAHs (OH-PAHs) were measured twice, six months apart. Logistic regression models were developed to estimate the associations of tertiles of urinary OH-PAH concentrations with cardiometabolic risk factors and excess weight, adjusted for the relevant covariates. The findings in all participants combined showed that increased risk of cardiometabolic risk factors and excess weight was associated with exposure to most of evaluated PAHs. Exposure to 1-hydroxypyrene was associated with higher risk of cardiometabolic risk factors in participants with excess weight. Exposure to 2-Naphtol was also associated with higher risk of cardiometabolic risk factors in both groups, but the associations were not significant (p < 0.1). For participants without cardiometabolic risk factors, exposure to 2-naphtol, 9-phenanthrol, and ∑ OH-PAH was associated with increased risk of obesity. For participants with cardiometabolic risk factors, we observed similar pattern of associations for 2-naphtol and ∑ OH-PAH, but the associations were not statistically significant (p < 0.1). We found that exposure to PAHs could possibly explain, in part, the cardiometabolic risk factors in children with excess weight as well as obesity in children with normal cardiometabolic profile.
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http://dx.doi.org/10.1016/j.envint.2018.05.048DOI Listing
September 2018

An innovative approach to attached cultivation of Chlorella vulgaris using different materials.

Environ Sci Pollut Res Int 2018 Jul 10;25(20):20097-20105. Epub 2018 May 10.

Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, 81676-36954, Iran.

This article investigates the innovative attached cultivation of Chlorella vulgaris (C. vulgaris) using different materials as an alternative to high capital techniques of harvesting such as centrifugation, flocculation, and filtration. A simple attached algal cultivation system was proposed that was equipped by 10 submerged supporting materials which can harvest algal cells, efficiently. The effect of operational parameters such as light intensity, the rate of aeration, and auto-harvesting time was investigated. A chip, durable, and abundant cellulosic material (Kaldnes carriers covered by kenafs, KCCKs) was proposed for auto-harvesting C. vulgaris cells. The results revealed that optimum aeration rate, light intensity, and auto-harvesting of microalgal cells were 3.6 vvm, 10,548 W/m, and 12 days, respectively. Six of these KCCKs had the highest biofilm formation percent up to 33%. In this condition, the rate of cell growth increased to 0.6 mg/cm. Therefore, this system can be used for appropriate auto-harvesting of microalgae in the attached growth systems. C. vulgaris biomass composition is valuable for biodiesel, bioethanol, and animal protein production.
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http://dx.doi.org/10.1007/s11356-018-2177-xDOI Listing
July 2018