Publications by authors named "Shahrokh Nazmara"

62 Publications

The presence of SARS-CoV-2 in raw and treated wastewater in 3 cities of Iran: Tehran, Qom and Anzali during coronavirus disease 2019 (COVID-19) outbreak.

J Environ Health Sci Eng 2021 Feb 24:1-12. Epub 2021 Feb 24.

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

This study aimed to identifying the presence of SARS-CoV-2 RNA in raw and treated wastewater during the COVID-19 outbreak in Tehran, Qom and Anzali cities (Iran). From three wastewater treatment plants (WWTPs), 28 treated and untreated wastewater composite samples were collected from April 4 to May 2, 2020. In this study, polyethylene glycol 6000 (PEG 6000) was used through one-step real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) for identification of RNA viruses. SARS-CoV-2 RNA was elicited from wastewater composite samples in all inlet samples taken from the three above mentioned cities. The results of outlet samples were as follows: 1) Results from Qom and East Anzali outlets showed no trace of SARS-CoV-2 RNA despite the difference in treatment disinfection method used (chlorine vs. ultraviolet (UV) disinfection). 2. In Tehran, SARS-CoV-2 RNA was not detected in any of the outlet samples taken from the modules disinfected by UV. Out of the four samples taken from the modules disinfected by chlorine, two were positive for the SARS-CoV-2 RNA which could have been caused by deficiencies in operation and maintenance. It can be concluded that meeting the standards of operation and maintenance (O&M) in WWTPs can considerably ensure that wastewater does not act as one of the roots of transmission for the disease.
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http://dx.doi.org/10.1007/s40201-021-00629-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7903026PMC
February 2021

Process modeling, characterization, optimization, and mechanisms of fluoride adsorption using magnetic agro-based adsorbent.

J Environ Manage 2021 Feb 19;286:112173. Epub 2021 Feb 19.

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

In this study, fluoride removal from polluted potable water using magnetic carbon-based adsorbents derived from agricultural biomass was thoroughly investigated. An experimental matrix is designed considering the interactive effects of independent process variables (pH, adsorbent dose, contact time, and initial fluoride concentration) on the removal efficiency. Isotherms and kinetics studies, as well as anions interactions, were also investigated to understand the adsorption mechanisms further. The model parameters of isotherms and kinetics are estimated using nonlinear differential evolution optimization (DEO). Approaches like adaptive neuro-fuzzy inference system (ANFIS) and response surface methodology (RSM) are implemented to predict the fluoride removal and identify the optimal process values. The optimum removal efficiency of GAC-FeO (89.34%) was found to be higher than that of PAC-FeO (85.14%). Kinetics experiments indicated that they follow the intraparticle diffusion model, and adsorption isotherms indicated that they follow Langmuir and Freundlich models. Both PAC-FeO and GAC-FeO adsorbents have shown an adsorption capacity of 1.20 and 2.74 mg/g, respectively. The model predictions from ANFIS have a strong correlation with experimental results and superior to RSM predictions. The shape of the contours depicts the nonlinearity of the interactive effects and the mechanisms in the adsorption process.
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http://dx.doi.org/10.1016/j.jenvman.2021.112173DOI Listing
February 2021

Associations between short term exposure to ambient particulate matter from dust storm and anthropogenic sources and inflammatory biomarkers in healthy young adults.

Sci Total Environ 2021 Mar 14;761:144503. Epub 2020 Dec 14.

Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran; Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

This study examined the association between particulate matter from anthropogenic and natural sources and inflammatory biomarkers, including hs-CRP, IL-6, sTNF-RII, and WBCs, in two groups of healthy young subjects. We followed up subjects of two panels (16 to 22 years old), including 22 subjects selected from the urban area (Tehran city) with high-level pollution background and 22 subjects selected from the rural area (Ahmadabad) with low-level pollution background. In each group, we collected 4 times blood samples in various air pollution conditions, In the subjects of the urban group, there was a substantial difference (p < 0.05) between inversion days and cold season control days, and between dust storm days and warm season control days for concentrations of hs-CRP, IL-6, and WBCs biomarkers. In the subjects of the rural group, a significant difference could be detected in the concentration of hs-CRP, IL-6, and WBCs biomarkers (p < 0.05) between inversion days and cold season control days, and between dust storm and warm control days. We found that the difference in concentrations of hs-CRP, IL-6, and WBCs biomarkers between dust storm days and warm control conditions in the rural group were higher than the difference in inversion and cold control conditions, which can be attributed to low background air pollution in the rural area. In the urban area, the health effect of anthropogenic sources of PM is higher than the dust storm condition, which can be attributed to the stronger effect of anthropogenic pollution effect.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144503DOI Listing
March 2021

Evaluating the performance of coupled MFC-MEC with graphite felt/MWCNTs polyscale electrode in landfill leachate treatment, and bioelectricity and biogas production.

J Environ Health Sci Eng 2020 Dec 16;18(2):1067-1082. Epub 2020 Sep 16.

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

Purpose: A bioelectricity producing system was configured by connecting to a microbial electrolysis cell producing hydrogen, in which both systems were without mediator, to treatment the landfill leachate of the and generate bioelectricity and hydrogen.

Methods: The anode electrode was made with MWCNTs polyscale coating on graphite felt and the cathode electrode with activated carbon coating on carbon cloth. In the MFC-MEC coupled system, the electrodes were connected in series using copper wire. The system was set up in a fed-batch mode and the landfill synthetic leachate was injected into the anode MFC-MEC chamber as fuel.

Results: In MFC, the highest voltage, current density and power density were 1114 mV, 44.2A/m and 49.24 W/m, respectively. The maximum of the coulombic efficiency system was 94.10%. The highest removed COD, NH-N and P was 97.38%, 79.56% and 74.61%, respectively. In the MEC, the maximum of voltage input, current density and power density was 1106 mV, 43.88 A/mand 48.54 W/m, respectively. The maximum coulombic efficiency system was 125.54%. Also the highest removed COD, NH-N and P was 97.46%, 78.81% and 76.25%, respectively. The highest biogas production rate and its yield were 39 mL/L.d, and 0.0118 L/g CODrem, respectively.

Conclusion: This study found that the MFC-MEC coupled system had promising potential for strong wastewaters treatment, such as the leachate of landfill; and the in-site use of generated electricity and the production of useful fuels such as biogas.
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http://dx.doi.org/10.1007/s40201-020-00528-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721933PMC
December 2020

The effects of ventilation and building characteristics on indoor air quality in waterpipe cafés.

J Expo Sci Environ Epidemiol 2020 09 18;30(5):805-813. Epub 2020 Jun 18.

Department of Occupational Health Engineering, School of Public Health, Ardabil University of Medical Sciences, Ardabil, Iran.

To determine the concentration of carbon monoxide (CO) and particulate matter (PMs), indoor air samples were collected from 60 waterpipe cafés in Ardabil city of Iran. Moreover, the influence of several structural, operational, and ventilation system were evaluated on the concentration of the selected pollutants. The results showed that the mean concentration of CO (12.0 ± 7.2 mg/m) and PMs (PM = 171.5 ± 119.6 μg/m, PM = 303.3 ± 201.9 μg/m, PM = 440.3 ± 272.2 μg/m) were notably higher than the guideline levels. According to the results, open face/café area was influenced by the natural ventilation rate and the mean air exchange rate was 3.1 ± 1.1 min. The natural ventilation has a functional role on air quality of the cafes, and fan-type mechanical ventilation was influencing factor on CO concentration when the natural ventilation was restricted. "Type of used charcoal" had the highest influence on the releasing of pollutants inside the cafés as the pollutant concentrations were lower for simple (raw) charcoal compared with the favored (aromatic) one. The results indicated that the building characteristics and natural ventilation considerably affect air quality of the cafes.
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http://dx.doi.org/10.1038/s41370-020-0240-4DOI Listing
September 2020

The acute effects of short term exposure to particulate matter from natural and anthropogenic sources on inflammation and coagulation markers in healthy young adults.

Sci Total Environ 2020 Sep 15;735:139417. Epub 2020 May 15.

Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

Airborne particulate matter is associated with increasing the risk of cardiovascular diseases. The purpose of this study was to investigate the association between air pollution conditions and MDA, vWF, and fibrinogen markers in the blood of two panels of healthy young individuals in an urban area in Tehran city with a high air pollution background and another group was living in a rural area (Ahmad Abad Mostofi), with a low air pollution background. In each group, 4 blood samples were taken as follows: one in inversion days, the second in winter, but during the existence of normal condition in terms of air pollution, the third sample in the spring during the normal condition in terms of air pollution and the fourth sample during the dust storm conditions. In the urban and rural groups, there was a significant difference between the concentration of MDA, vWF, fibrinogen between inversion and cold season control conditions, and between dust storm conditions and warm season control conditions (p < 0.05). The results showed that the association of dust storm condition on the measured biomarkers was stronger than the inversion condition, which health consideration in the dust conditions be taken into account similar to the inversion conditions.
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http://dx.doi.org/10.1016/j.scitotenv.2020.139417DOI Listing
September 2020

Can respirator face masks in a developing country reduce exposure to ambient particulate matter?

J Expo Sci Environ Epidemiol 2020 07 21;30(4):606-617. Epub 2020 Apr 21.

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

Respirator face masks (RFMs) as a personal-level intervention is increasingly being utilized to reduce ambient particulate matter (PM) exposure, globally. We tested the effectiveness of 50 commercially available ones in reducing the exposure of ambient particle number concentrations (PNC), PM, PM, and PM (PM ≤ 10, 2.5, and 1 μm in diameter, respectively) in a traffic-affected urban site in Tehran. To examine the efficiency of RFMs, we applied a specific experimental setup including vacuum pumps, dummy heads, connecting tubes, glass chambers, and GRIMM Aerosol Spectrometer to measure all metrics after dummy heads. The average effectiveness of RFMs was in the range of 0.7-83.5%, 3.5-68.1%, 0.8-46.1%, and 0.4-32.2% in reducing ambient PNC, PM, PM, and PM, respectively. Considering all metrics, the highest effectiveness was observed always for Biomask, followed by 3 M 9332, due to their well-designed physical characteristics (e.g., adjustable nose clip for any face/nose shape, and size, soft inner material in the nose panel to provide a secure seal against leakage, adjustable or elasticated straps/ear loops to better adjust on any face). Biomask reduced ambient PM with a mean value of 94.6 μg m (minimum-maximum: 51.7-100.3 μg m), whereas it filtered on average just 29.0 μg m (25.7-43.5 μg m) of ambient PM and 18.2 μg m (14.7-21.8 μg m) of PM. A fuzzy analytical hierarchy process to find the most important design-related factors of RFMs affecting their effectiveness, which showed the exhalation valve and its diaphragm (20.4%), nose clip (19.7%), and cheek flaps (18.6%) are ranked as the main design-related variables. The fuzzy technique for order preference by similarity to ideal solution indicated that Biomask and 3M 9332 had scores of 1 and 0.97, the highest scores compared with other RFMs. This study provides crucial evidence-based results to elucidate the effectiveness and design-related factors of RFMs in real-environmental circumstances.
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http://dx.doi.org/10.1038/s41370-020-0222-6DOI Listing
July 2020

The Concentration and Probabilistic Health Risk of Potentially Toxic Elements (PTEs) in Edible Mushrooms (Wild and Cultivated) Samples Collected from Different Cities of Iran.

Biol Trace Elem Res 2021 Jan 20;199(1):389-400. Epub 2020 Apr 20.

Department of Food Science, Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.

The present study was devoted to investigate the PTE concentrations including cadmium (Cd), chromium (Cr), copper(Cu), iron (Fe), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), arsenic(As), and zinc (Zn) among six types of edible wild, 23 cultivated mushroom samples collected from Iran's market by the aid of an inductively coupled plasma-optical emission spectrometry (ICP-OES). Also, the related health risk assessment was established by the aid of the Monte Carlo simulation method (MSC). The limit of detection (LOD) and limit of quantification (LOQ) were ranged 0.001-0.048 and 0.003-0.160 ppm, respectively. The concentrations of As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn were determined in the ranges of 0.003-11. 5, 0.0008-5.89, 0.32-26.32, 9.15-110.08, 15.25-751.17, 0.16-2.24, 2.1-60.47, 1.21-24.22, 0.16-8.92, and 37.13-268.11 mg kg, respectively. According to findings, highest mean concentration of Cr in both types of mushrooms (cultivated and wild) was lower than recommended level by Codex Alimentarius/Food and Agriculture Organization/World Health Organization (CODEX/FAO/WHO) while the corresponding values for Hg (0.87 mg kg), As (1.39 mg kg), Ni (10.08 mg kg), Cu (36.65 mg kg), Cr (10.44 mg kg), Cd (0.589 mg kg), Fe (201.04 mg kg), Mn (10.30 mg kg), Zn (2266.43 mg kg), and Pb (3.81 mg kg) were higher than related standard levels. According to the health risk assessment, no concern regarding the non-carcinogenic risk due to the ingestion of PTEs via the consumption of the edible mushrooms, except Hg in wild mushrooms for children, was noted.
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http://dx.doi.org/10.1007/s12011-020-02130-xDOI Listing
January 2021

Modeling and optimizing parameters affecting hexavalent chromium adsorption from aqueous solutions using Ti-XAD7 nanocomposite: RSM-CCD approach, kinetic, and isotherm studies.

J Environ Health Sci Eng 2019 Dec 11;17(2):873-888. Epub 2019 Dec 11.

7Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.

Background: Due to the high toxicity of chromium, particularly as Hexavalent chromium Cr (VI), it is removed from industrial effluents before their discharge into the environment by a variety of methods, including loading catalysts onto the polymeric supports. This study focused on the removal of Cr(VI) from aqueous solutions using Amberlite XAD7 resin loaded titanium dioxide (Ti-XAD7).

Methods: Ti-XAD7 was synthesized using Amberlite XAD-7 impregnated with titanium tetraethoxide. The prepared Ti-XAD7 was characterized by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Isotherms and kinetic studies were carried out to describe the adsorption behavior of adsorbent for the removal of Cr(VI) ions. Quadratic models considering independent variables, i.e. the initial Cr(VI) concentration, adsorbent dosage, time, and pH, were evaluated and optimized to describe the behavior of Cr(VI) adsorption onto the Ti-XAD7 using RSM based on a Five-level-four-factor CCD approach.

Results: The accuracy and the fitting of the model were evaluated by ANOVA with R > 0.725 and value = 5.221 × 10. The optimum conditions for the adsorption process were an initial Cr(VI) concentration 2750 ppb, contact time of 51.53 min, pH of 8.7, and Ti-XAD7 dosage of 5.05 g/L. The results revealed that the Langmuir and Sips isotherm models with R = 0.998 and 0.999 were the The adsorption capacity of Ti-XAD7 and R constant were 2.73 mg/g and 0.063-0.076 based on the Langmuir isotherm, respectively. Kinetic studies also indicated that the adsorption behavior of Cr(VI) was acceptably explained by the Elovich kinetic model with a good fitting (R = 0.97).

Conclusions: Comparison of the Ti-XAD7 and XAD7 yield in chromium adsorption showed that modified XAD7 had higher removal efficiency (about 98%) compared to XAD7 alone.
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http://dx.doi.org/10.1007/s40201-019-00405-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6985374PMC
December 2019

Photochemical degradation of toluene in gas-phase under UV/visible light graphene oxide-TiO nanocomposite: influential operating factors, optimization, and modeling.

J Environ Health Sci Eng 2019 Dec 23;17(2):671-683. Epub 2019 Jul 23.

1Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

The current study aimed to investigate the removal efficiency of toluene using synthesized titanium dioxide-graphene oxide composites under visible light and UV irradiation. The characterization of synthesized composites was examined by field emission scanning electron microscope equipped with energy dispersive, X-ray diffraction and fourier transforms infrared. In order to find the optimum of the main experimental parameters affecting the removal efficiency of toluene including the length of the reactor, initial concentration, and flow rates, central composite design together with response surface methodology with R software was used. The initial concentration of toluene in the inlet of the reactor as well as its concentration in the outlet was measured using gas chromatography with the flame ionization detector. Analysis of variance results for the quadratic model showed that the highly significant and simple linear regression was established as a predicting model. Multiple and adjusted R were 0.965 and 0.974 for UV irradiation GO-TiO model and 0.951 and 0.959 for visible light GO-TiO model, respectively. As such, the differences less than 0.2 between multiple and adjusted R in two models indicate that two examined models were fitted well. The highest removal efficiency of toluene using UV irradiation GO-TiO and visible light GO-TiO was obtained at optimum condition; length of reactor 40 cm, initial concentration of 0.1 ppm, and flow rate equal to 1 l min, with 97.7 and 77.2%, respectively. The results indicated that the removal efficiency of toluene increased considerably with rising the length of the reactor, decreasing flow rates, and initial concentration.
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http://dx.doi.org/10.1007/s40201-019-00382-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6985382PMC
December 2019

Levels and ecological and health risk assessment of PM-bound heavy metals in the northern part of the Persian Gulf.

Environ Sci Pollut Res Int 2020 Feb 17;27(5):5305-5313. Epub 2019 Dec 17.

Department of Environmental Health Engineering, Faculty of Health, Bushehr University of Medical Sciences, Bushehr, Iran.

Bushehr, a port along the northern part of the Persian Gulf, has repeatedly encountered dust storms in recent years but there is not been a comprehensive study on the PM contents in this region. The present study reports the characteristics and health risks of atmospheric PM-bound heavy metals (HMs) in Bushehr from December 2016 to September 2017. A total of 46 samples were analyzed, and a high volume air sampler equipped with quartz fiber filters was used for sampling. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was also used for HMs analyses. Risk assessment and hazard index (HI) of these metals were computed by using USEPA's exposure parameters. The results showed that the average 24-h mass concentration of PM ranged from 22.09 to 292.45 μg/m. The results also indicated that 95.65 and 82.61% of the samples were higher than WHO and EPA guidelines for 24-h PM. Also there was no statistically significant relationship between wind direction and PM.The average concentration levels of seven measured metals (Cd, Co, Cr, Fe, Ni, Pb, and V) in the PM samples were in the range of 6.03 ng/m to 1335.94 ng/m, and the order of their concentration was Fe > Ni > Pb > Cr > Cd > V > Co. Principal component analysis (PCA) showed that PM-bound heavy metals were categorized in three groups. The ecological risk level of calculated metals was very significant, and the major contribution of the ecological risk was related to Cd. The highest HQ in children and adults was related to Cr, and overall HI in children was higher than adults. Also the RI values of Cr in both groups of children and adults were indicated high risk of developing cancer in human.
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http://dx.doi.org/10.1007/s11356-019-07272-7DOI Listing
February 2020

Characteristics and health risk assessment of polycyclic aromatic hydrocarbons associated with dust in household evaporative coolers.

Environ Pollut 2020 Jan 16;256:113379. Epub 2019 Oct 16.

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

This study reports a characterization of indoor polycyclic aromatic hydrocarbons (PAHs) associated with dust (dust-PAHs) in household evaporative coolers and their associated health effects. Extensive analysis showed that the indoor dust-PAHs stemmed mostly from pyrogenic sources (vehicular emissions) with mean total concentrations limited between 131 and 429 ng g. The distribution pattern of PAHs based on number of rings exhibited the following order of decreasing relative abundance: 4 > 3 > 5 > 6 > 2 rings. Results indicate that the mutagenicity of dust-PAHs exceeded their carcinogenicity, but that the potential carcinogenic effects are still significant. The mean lifetime cancer risk for different age groups for three pathways based on Model 2 (dermal (1.39 × 10 to 1.91 × 10), ingestion (2.13 × 10 to 8.08 × 10) and inhalation (1.62 × 10 to 4.06 × 10)) was 7.4-146 times higher than values predicted by Model 1 (dermal (5.13 × 10 to 3.03 × 10), ingestion (9.34 × 10 to 1.31 × 10) and inhalation (7.13 × 10 to 1.68 × 10)). Hence, exposure to dust-PAHs in household evaporative coolers lead to high risk, especially for children (less than 11 years) (HQ = 2.71 × 10 to 54.8 and LTCRs = 7.13 × 10 to 1.39 × 10). Strategies should be considered to eliminate such pollutants to protect people, especially children, from the non-carcinogenic and carcinogenic effects by changing household evaporative coolers with other cooling systems.
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http://dx.doi.org/10.1016/j.envpol.2019.113379DOI Listing
January 2020

Bioaccessibility analysis of toxic metals in consumed rice through an in vitro human digestion model - Comparison of calculated human health risk from raw, cooked and digested rice.

Food Chem 2019 Nov 3;299:125126. Epub 2019 Jul 3.

Department of Environmental Health, School of Public Health, Tehran University of Medical Science, Tehran, Iran; Center for Research Methodology and Data Analysis (CRMDA), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

The health risk assessment of exposure to toxic metals through the consumption food crops is very important. The present study was aimed to investigate the bioaccessibility of toxic metals (including arsenic, lead and cadmium) in rice through an in vitro gastrointestinal digestion model, and assess health risks associated with these metals in raw, cooked and digested rice. Total and bioaccessible concentration of metals were measured by introducing the prepared samples into the inductively coupled plasma-optical emission spectroscopy. Based on the results, the bioaccessible toxic metals in gastric phase were significantly higher than that in both oral and small intestinal phases. The estimated concentrations of these metals in the raw and cooked rice are very far from the actual exposure state. Therefore, to assess the extent of health risks associated with the subjected toxic metals through the rice consumption, the actual exposure value of the metals (bioaccessible value) should be considered.
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http://dx.doi.org/10.1016/j.foodchem.2019.125126DOI Listing
November 2019

Advantages and disadvantages of different pre-cooking and cooking methods in removal of essential and toxic metals from various rice types- human health risk assessment in Tehran households, Iran.

Ecotoxicol Environ Saf 2019 Jul 18;175:128-137. Epub 2019 Mar 18.

Department of Environmental Health, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

The aim of present study was to evaluate the effects of different pre-cooking and cooking methods on the concentration of toxic (As, Cd and Pb) and essential (Fe, Cu, Co and Zn) metals in widely consumed rice types by Tehran households, Iran. In this regard, a total of 90 samples were obtained from Iranian, Pakistani and Indian rice brands (30 samples from each brand), and were examined in order to determine the concentration of toxic metals including As, Cd, Pb, Fe, Zn, Co and Cu using ICP-OES. Among these rice brands, the most contaminated one was selected in order to evaluate the effects of washing and soaking processes in different time points (1, 5 and 12 h), as well as different cooking methods (Rinsing and Kateh) in reducing the concentration of subjected metals. Nine samples were analyzed for each process, which were 54 samples in total. Our results show that the preparation and cooking methods applied for all rice brands (except for Indian rice) could effectively reduce the non-carcinogenic risk associated with these metals to the acceptable level; however, this is not true about the carcinogenic risk associated with arsenic. Finally, according to our findings it can be concluded that all cooking methods can lead to considerable removal of rice toxic metals (this is partially true about all available rice brands in Iran), however, a large amount of essential metals were also eliminated by these methods. Moreover, after cooking of different rice types in Iran, this food has still carcinogenic risk associated with arsenic.
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http://dx.doi.org/10.1016/j.ecoenv.2019.03.056DOI Listing
July 2019

Spatial variation and quantitative screening level assessment of human risk from boron exposure in groundwater resources of western edge of the Lake Urmia, Iran.

Int J Environ Health Res 2020 Jun 21;30(3):237-250. Epub 2019 Mar 21.

School of Health, Tehran University of Medical Sciences, Tehran, Iran.

Boron is a ubiquitous element and exposure to high concentrations of boron in drinking water may lead to health outcomes. This study aimed to analyze boron in rural drinking water resources located at the west of Urmia Lake. An innovative risk matrix was developed for faster assessment of risk status and adaptation of mitigation approaches. The mean boron concentration in 121 drinking water sources from 301 villages obtained 1477 ± 1683 μg/L. In the west of Urmia lake and northwestern parts of the lake (east of Salmas city), boron concentrations were up to twice the World Health Organization (WHO) guidelines. Using regional screening levels calculator of the U.S. Environmental Protection Agency (US.EPA), as a deterministic risk assessment model, the total risks/Non-carcinogenic hazard index (HI) risks from exposure to 13,000 and 2600 μg/L of boron obtained 1.94E+00 and 3.91E-01, respectively. More investigations are recommended for better understanding of the extent of contamination in the study area.
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http://dx.doi.org/10.1080/09603123.2019.1590539DOI Listing
June 2020

Comparative investigation of argon and argon/oxygen plasma performance for Perchloroethylene (PCE) removal from aqueous solution: optimization and kinetic study.

J Environ Health Sci Eng 2018 Dec 2;16(2):277-287. Epub 2018 Oct 2.

1Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: The aim of this study is evaluation of the perchloroethylene degradation from aqueous solutions by non-thermal plasma produced in dielectric barrier discharge reactor in two different scenarios: first plasma generated with 225 cc/min mixture of oxygen and argon flow (12% gas ratio of O/Ar), and in the second scenario plasma generated with 225 cc/min of pure argon gas.

Methods: Design studies were performed using response surface methodology and central composite design. All experiments with the selected levels of independent parameters including the initial concentration of perchloroethylene (5-100 mg/L), voltage (20-5 kv) and contact time (15-180 s) was implemented, and 29 tests were proposed by using response surface methodology and central composite design was performed in two experimental scenarios.

Results: Results showed that the Pseudo first-order kinetics coefficient of perchloroethylene degradation in the mixture of oxygen and argon and pure argon scenario under the optimum conditions were 0.024 and 0.016 S respectively. Results conveyed that in order to achieve the highest removal efficiency (100%), the values of contact time, perchloroethylene concentration and voltage variables were predicted 169.55 s, 74.3 mg/l, 18.86 kv respectively in mixture of oxygen and argon scenario and also were predicted 203 s, 85.22 mg/l, 20.39 kv respectively in pure argon scenario.

Conclusions: In the recent study dielectric barrier discharge was an efficient method for perchloroethylene removal with both oxygen an argon mixture and pure argon as input gas. Both input voltage and reaction time has positive effect on perchloroethylene removal; but initial perchloroethylene concentration has negative effect on perchloroethylene removal. Comparison of two plasma scenarios with different input gas shown that plasma generated by mixture of oxygen and argon gas was more powerful and had higher removal efficiency and degradation kinetics than the plasma generated by pure argon gas.
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http://dx.doi.org/10.1007/s40201-018-0316-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277337PMC
December 2018

Physiochemical characteristics and oxidative potential of ambient air particulate matter (PM) during dust and non-dust storm events: a case study in Tehran, Iran.

J Environ Health Sci Eng 2018 Dec 29;16(2):147-158. Epub 2018 Jun 29.

7Health and Environment Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.

In the present study, we investigated the characteristics of metal(loid)s, polycyclic aromatic hydrocarbons (PAHs) and oxidative potential (OP) in PM during dust and non-dust days in a rural and an urban area in Tehran. Water-soluble ions, metal(loid)s, PAHs, and OP were measured using ion chromatography (IC), inductively coupled plasma optical emission spectrometer (ICP-OES) and gas chromatography/mass spectrometry (GC-MS), and dithiothreitol (DTT) assay respectively. The results showed that the average concentrations of ambient PM were 284 ± 90.4 and 123 ± 31.4 μg m on dusty and regular days in urban areas respectively, and were 258 ± 48.3 and 124 ± 41.4 μg m on dusty and regular days in rural areas, respectively; these values were 95% above the World Health Organization (WHO) guideline level. The crustal elements Na, Mg, Ca, Al, Si, Fe and Ti were the dominant for PM on dusty days, and NO and SO were dominant for PM on regular days. The average ± SD concentrations of total PAHs were 34.3 ± 22.5 and 55.1 ± 28.3 ng m on dusty and regular days, respectively, with the maximum value occurring on inversion days. The average OP was 8.90 ± 7.15 and 1.41 ± 0.35 and was 11.4 ± 3.97 and 19.9 ± 8.67 (nmol min μg PM) for water and methanol extracts on dusty and regular days, respectively, with the lowest value occurring on dusty days. The OP was highly associated with Cu and Mn. Briefly; the results of this study demonstrate that OP is mass independent and consequence a promising proxy for PM mass.
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http://dx.doi.org/10.1007/s40201-018-0303-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277329PMC
December 2018

The reduction of toxic metals of various rice types by different preparation and cooking processes - Human health risk assessment in Tehran households, Iran.

Food Chem 2019 May 19;280:294-302. Epub 2018 Dec 19.

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

In this study, the effect of washing, soaking (1, 5 and 12 h), and cooking rice methods including Rinsed (boiling in excess water) and Kateh (conventional) cooking on the reduction of the arsenic (As), lead (Pb), and cadmium (Cd) were evaluated. The results showed that the rinsed cooking has higher efficiency for removal of toxic metals (As = 42.3%, Pb = 42.9% and = 27.6%) than Kateh method (As = 26.9%, Pb = 26.9% and = 20.9%). Additionally, by increasing of rice soaking time from 1 to 12 h, the toxic metals removal was increased up to 37.1%, 42.6% and 16.6% for As, Pb and Cd, respectively. Although the toxic metals reduction was such that the non-carcinogenic risk was regarded as acceptable level after all processes, for arsenic, these reductions did not lower the carcinogenic risk to an acceptable level. Finally, it is suggested that Tehran households, after washing and soaking to 5 h, then cook it by rinse method.
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http://dx.doi.org/10.1016/j.foodchem.2018.12.060DOI Listing
May 2019

Human health risk assessment for some toxic metals in widely consumed rice brands (domestic and imported) in Tehran, Iran: Uncertainty and sensitivity analysis.

Food Chem 2019 Mar 19;277:145-155. Epub 2018 Oct 19.

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

The aim of this study was to evaluate the contamination of widely consumed rice brands in Tehran, Iran with three heavy metals: arsenic, lead, and cadmium. To this end, 250 rice samples were collected and 90 samples out of them were analyzed using ICP-MS. Finally, human health risk assessment were performed. Our results showed that the average of lead, cadmium, and arsenic concentrations in Indian rice type was significantly higher than Iranian and Pakistani types (P < 0.05). Among the three metals, the highest impact on the total value of non-carcinogenic risk was related to As. In addition, the non-carcinogenic risk value only for the Indian rice type, was above the permitted level (1.0). Also, we found that the carcinogenic risk of arsenic in all three rice types was higher than the acceptable limit (10). According to findings, special attention should be paid to reducing arsenic especially in Indian rice through interventions.
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http://dx.doi.org/10.1016/j.foodchem.2018.10.090DOI Listing
March 2019

Concentration and type of bioaerosols before and after conventional disinfection and sterilization procedures inside hospital operating rooms.

Ecotoxicol Environ Saf 2018 Nov 17;164:277-282. Epub 2018 Aug 17.

Department of Occupational Health Engineering, School of Public Health, Shiraz University of Medical Sciences, Shiraz, Iran. Electronic address:

Operating rooms (ORs) in hospitals are sensitive wards because patients can get infections. This work aimed to characterize the type and concentration of bioaerosols in nine ORs of an educational hospital before and after sterilization and disinfection. During 2017, fungal samples were incubated at 25-28 °C for 3-7 days and bacterial samples at 37 °C for 24-48 h. The study results showed that the concentrations of fungi before cleaning procedures (for both of disinfection and sterilization) were limited from 4.83 to 18.40 CFU/m and after cleaning procedures ranged from 1.90 to 8.90 CFU/m. In addition, the concentrations of bacteria before cleaning procedures were limited 14.65-167.40 CFU/m and after cleaning procedures ranged from 9.50 to 38.40 CFU/m. The difference between the mean concentrations of airborne bioaerosols before and after sterilization was significantly different than the suggested value of 30 CFU/m (p ≤ 0.05). The bacterial concentration was higher than the recommended value (30 CFU/m) in 41% of the ORs. The main fungal species identified in the indoor air of ORs (before vs. after sterilization) were A. fumigatus (25.6 vs. 18.3%), A. Niger (11.6 vs. 5.8%), Penicillium spp. (5.5 vs. 3.3%), Alternaria spp. (2.8 vs. 0.7%), Fusarium spp. (9.7 vs. 3.7%), Mucor spp. (15 vs. 12.7%), Cephalotrichum spp. (1.7 vs. 0.8%), A. Flavus (24.6 vs. 18.5%), Cladosporium spp. (2.6 vs. 0.8%), and Trichoderma spp. (0 vs. 0.9%). The growth of biological species even after sterilization and disinfection likely resulted from factors including poor ventilation, sweeping of OR floors, inadequate HVAC filtration, high humidity, and also lack of optimum management of infectious waste after surgery. Designing well-constructed ventilation and air-conditioning systems, replacing HEPA filters, implementing more stringent, frequent, and comprehensive disinfection procedures, and controlling temperature and humidity can help decrease bioaerosols in ORs.
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http://dx.doi.org/10.1016/j.ecoenv.2018.08.034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6151147PMC
November 2018

Data on trend changes of drinking groundwater resources quality: A case study in Abhar.

Data Brief 2018 Apr 31;17:424-430. Epub 2018 Jan 31.

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

The data of this study was to determine the groundwater quality trend changes in Abhar city (Iran) during one decade (2002-2016). In the first and end year of the study period, the Mean±SD of total hardness (as calcium carbonate, mg/l), electrical conductivity (as micromhos/cm) and total dissolved solid in the first and end year of the study period were 192.69±56.83, 235.25±84.73 and 606.21±194.69, 744.55±288.52 and 348.79±106.81, 464.71±183.52 respectively. On the basis of Pearson correlation coefficient, the ascending trend of some parameters concentration with time was significant at the level of 95% of confidence limits (α ≤ 0.05).
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http://dx.doi.org/10.1016/j.dib.2018.01.032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5988296PMC
April 2018

Determination of heavy metal content of processed fruit products from Tehran's market using ICP- OES: A risk assessment study.

Food Chem Toxicol 2018 May 3;115:436-446. Epub 2018 Apr 3.

Department of Food Science, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil. Electronic address:

In this study, the levels of Cd, Hg, Sn, Al, Pb and As of 72 samples (36 samples for fruits juices and 36 samples for fruits canned) of three different brands including of Peach, Orange, Cherry, and Pineapple (18 samples of each fruits) marketed in Tehran, Iran (2015) were evaluated using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) technique. Also, Probabilistic risk assessment (non-carcinogenic and carcinogenic risks) was estimated by models include target hazard quotient (THQ) and cancer risk (CR) in the Monte Carlo Simulation (MCS) model. However, all samples were contaminated with the heavy metals investigated, most of them not surpassed established standards. The range of concentration for Al, Sn, As, Cd, Hg, and Pb as average in fruit juices were reported as 340.62 (65.17-1039.2), 72.33 (49.76-119.4), 3.76 (1.137-18.36), 2.12 (0.89-3.44), 0.351 and 40.86 (27.87-66.1) μg/kg, respectively. The level of heavy metals measured in different kinds of fruit juices was ranked as Al > Sn > Pb > As > Cd > Hg, and for fruits canned this rank was Pb > Al > Sn > As > Cd > Hg. The range of concentration for Al, Sn, As, Cd, Hg, and Pb in fruits canned were reported as 361.23 (43.15-1121.2), 101.42 (71.45-141.61), 3.92 (1.279-19.50), 2.78 (1.09-5.56), 0.35 and 690.54 (470.56-910.14) μg/kg, respectively. The lead (Pb) concentration in 97.22% (35 out of 36 samples) of fruit juices samples surpassed Codex limit (0.05 mg/kg) and in all samples of FC was lower than the legal limit of Codex limit (1 mg/kg). All of the samples had Tin (Sn) lower than the legal limit of Codex (fruit juices 100 mg/kg and FC 250 mg/kg). The MCS indicated that the rank order of heavy metals in both adults and children based on THQ was Al > Sn > As > Pb > Cd > Hg. The THQ of Al and Sn in the FJ and FC, for both adults, and children, was considerably higher than 1 value. Also, CR of As in both adults and children were higher than 1E-6 value. Although the mean concentration of heavy metal in the FJ and FC was lower than the standard limit, the MCS indicated that adults and children are at considerable non-carcinogenic and carcinogenic risks.
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http://dx.doi.org/10.1016/j.fct.2018.03.044DOI Listing
May 2018

Optimization of the synthesis and operational parameters for NOM removal with response surface methodology during nano-composite membrane filtration.

Water Sci Technol 2018 Mar;77(5-6):1558-1569

Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran E-mail: Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran; Center for Solid Waste Research (CSWR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.

The aim of this study was to investigate membrane synthesis by interfacial polymerization methods, the application of synthesized nano-composite membrane for natural organic matters (NOMs) removal from water, evaluation of fouling mechanism and antifouling properties. Polysulfone (PSf) was selected as a porous ultrafiltration membrane support and interfacial polymerization was done using tannic acid (TA) and Trimesoyl chloride (TMC) with central composite design (CCD). The effects of TA and TMC monomer concentrations, reaction time and post treatment temperature was evaluated. The synthesized membrane was characterized by field emission scanning electron microscope (FESEM), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and water contact angle. Based on the results, the optimum conditions for synthesizing nano-composite were: TA concentration of 0.27 g/L, TMC concentration of 0.22 g/L, reaction time of 68.29 min and temperature of 25.23 °C. The predicted optimum operational conditions were a NOM concentration of 6.429 mg/L; time of 10.931 min and applied pressure of 1.039 bar. The potential applications of the synthesized nano-composite membranes with interfacial polymerization can enhance water treatment.
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http://dx.doi.org/10.2166/wst.2018.037DOI Listing
March 2018

Environmental and biological monitoring of exposures to VOCs in a petrochemical complex in Iran.

Environ Sci Pollut Res Int 2018 Mar 19;25(7):6656-6667. Epub 2017 Dec 19.

Department of Environmental Health Engineering, Faculty of Health, Isfahan University of Medical Sciences, Hezar Jerib St., Isfahan, Iran.

Exposure to volatile organic compounds (VOCs) can cause cancers in human. This study aimed to measure the concentration of four VOCs including benzene, styrene, ethylbenzene, and phenol in ambient air of a petrochemical complex in Iran. Also, their urinary metabolites including phenol, mandelic acid (MA), and phenylglyoxylic acid (PGA) in the workers were monitored. Urine samples were collected before and after the 8-h workshift according to the NIOSH methods. They were analyzed by a gas chromatograph coupled with a flame ionization detector (GC-FID). High levels of the ambient VOCs were detected in the units of recovery and olefin. The levels of ethylbenzene and phenol were less than the guidelines suggested by NIOSH and ACGIH. However, in some cases, the amounts of benzene and styrene were higher than the guidelines. Excellent positive correlations were observed between VOCs exposure and their urinary metabolites (r  > 0.90), except for benzene (r  = 0.26). Our finding verified that urinary biomarkers can be applied as bioindicators for ambient exposure to VOCs. There is a risk of exposure to high levels of the pollutants in some of the sites, and it is necessary to adopt some preventive measures to reduce health risk.
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http://dx.doi.org/10.1007/s11356-017-1045-4DOI Listing
March 2018

Response surface methodology modeling to improve degradation of Chlorpyrifos in agriculture runoff using TiO solar photocatalytic in a raceway pond reactor.

Ecotoxicol Environ Saf 2018 Jan 2;147:919-925. Epub 2017 Oct 2.

Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

This paper deals with the use of a raceway pond reactor (RPR) as an alternative photoreactor for solar photocatalytic applications. Raceway pond reactors are common low-cost reactors which can treat large volumes of water. The experiments were carried out with TiO in the agriculture effluent spiked with Chlorpyrifos (CPF) at circumneutral pH. The Response Surface Methodology (RSM) was used to find the optimum process parameters to maximize CPF oxidation from the mathematical model equations developed in this study using R software. By ANOVA, p-value of lack of fit > 0.05 indicated that, the equation was well-fitted. The theoretical efficiency of CPF removal, under the optimum oxidation conditions with UV solar energy of around 697 ± 5.33 lux, was 84.01%, which is in close agreement with the mean experimental value (80 ± 1.42%) confirming that the response model was suitable for the optimization. As far as the authors know, this is the first study of CPF removal using RPR in agriculture runoff at circumneutral pH.
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http://dx.doi.org/10.1016/j.ecoenv.2017.09.062DOI Listing
January 2018

Haloacetic acids degradation by an efficient Ferrate/UV process: Byproduct analysis, kinetic study, and application of response surface methodology for modeling and optimization.

J Environ Manage 2017 Dec 4;203(Pt 1):218-228. Epub 2017 Aug 4.

Center for Water Quality Research, Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

Haloacetic acids (HAAs) after trihalomethanes are the second main group of chlorination byproducts. In this study, decomposition of the two most common HAAs in drinking water was studied by an advanced oxidation process using a combination of Ferrate [Fe(VI)] and UV irradiation. The decomposition rate was measured, and the byproducts formed during the process and the mass balances were also analyzed. HAAs were quantified by GC-ECD, and the final products including acetate and chloride ions were measured by ion chromatography (IC). A central composite design was used for the experimental design, and the effect of four variables including the initial HAA concentration, pH, Fe(VI) dosage, and contact time were investigated by response surface methodology (RSM). Dichloroacetic acid decomposed more easily than TCAA. Results show that when TCAA and DCAA were studied individually, the degradation rates were 0.0179 and 0.0632 min, respectively. When the HAAs were simultaneously placed in the reactor, the decomposition rates of both TCAA and DCAA decreased dramatically. In this case their decomposition rate constants decreased by 67% and 49%, respectively. In the mixture, the decomposition rate of DCAA was 2.5 times higher than that of TCAA. In summary, Fe(VI)/UV process can be used as a promising treatment option for the decomposition of recalcitrant organic pollutants such as HAAs, and RSM can be used for modeling and optimizing the process.
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http://dx.doi.org/10.1016/j.jenvman.2017.07.072DOI Listing
December 2017

Air- and Dust-Borne Fungi in Indoor and Outdoor Home of Allergic Patients in a Dust-Storm-Affected Area.

Immunol Invest 2017 Aug 25;46(6):577-589. Epub 2017 Jul 25.

a Department of Environmental Health Engineering , Faculty of Health, Bushehr University of Medical Sciences , Bushehr , Iran.

Despite the recent increases in fungi-induced allergic diseases, there is no report yet in the region of the Persian Gulf on concentration levels of fungi in relationship with health state. Therefore, our aim was to measure fungi prevalence as well as to evaluate the relationships between air- and dust-borne fungal genera and allergic diseases. A matched case-control study was carried out including 45 allergic cases and 45 age- and gender-matched controls for each individual. Indoor and outdoor dust and indoor air samples were collected from participant homes during May to October 2015. A Quick Take 30 Pump and sterile wet swab were used to determine fungal types and their amounts in the air (CFU/m) and dust (CFU/100 cm) samples, respectively. A significant reverse association was found between indoor dust-borne Alternaria and asthma (Odds ratio (OR) = 0.14, 95% CI = 0.02-0.86). Contrarily, increased levels of indoor air-borne Aspegillus fumigatus (OR = 2.00, 95% CI = 0.37-10.55) and Alternaria (OR = 3.00, 95% CI = 0.34-25.83) were correlated with asthma development. Also, correlation analysis showed a significant relation between indoor air-borne Penicillium levels and reactivity to skin prick test in asthmatic patients (p = 0.04). Our findings support the notion that fungal exposures can either cause or prevent the development of allergic diseases. Accordingly, appropriate measures should be taken for a better management of fungi-induced allergic diseases.
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http://dx.doi.org/10.1080/08820139.2017.1322102DOI Listing
August 2017

Erratum to: Biodegradation of total petroleum hydrocarbons from acidic sludge produced by re-refinery industries of waste oil using in-vessel composting.

J Environ Health Sci Eng 2017 20;15:13. Epub 2017 Jun 20.

Center for Solid Waste Research (CSWR), Institute for Environmental Research(IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran.

[This corrects the article DOI: 10.1186/s40201-017-0267-1.].
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http://dx.doi.org/10.1186/s40201-017-0275-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477681PMC
June 2017

Biodegradation of total petroleum hydrocarbons from acidic sludge produced by re-refinery industries of waste oil using in-vessel composting.

J Environ Health Sci Eng 2017 27;15. Epub 2017 Feb 27.

Center for Solid Waste Research (CSWR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran.

Background: In Iran, re-refinery industry has been developed many years ago based on the acid-clay treatment. Acidic sludge with high concentration of total petroleum hydrocarbon (TPH) is the final products of some facilities. In this study removal of TPH by aerated in-vessel composting was investigated.

Methods: In order to microorganisms seeding and nutrient providing, urban immature compost was added as an amendment to acidic sludge. The ratios of acidic sludge (AS) to compost were, 1:0 (as control), 1:5, 1:8, 1:10, 1:15, 1:20, 1:30, 1:40, 1:50, 1:75 and 1:100 (as dry basis) at a C: N: P ratio of 100:5:1 and 45-65% moisture content for 70 days.

Results: The removal efficiency in all reactors was more than 48%. The highest and lowest TPH removal was observed in 1:5 (71.56%) and 1:100 (48.53%) mixing ratios, respectively. The results of the control reactors showed that biological treatment was the main mechanism for TPH removal. Experimental data was fitted second order kinetic model ( > 0.8006). Degradation of TPH in 1:5 mixing ratio (k = 0.0038 gmg d; half-life = 3.08d) was nearly three times faster than 1:100 mixing ratio (k = 0.0238; half-life = 8.96d). The results of the control reactors showed that biological treatment was the main mechanism for TPH removal.

Conclusion: The results of this study revealed in-vessel composting with immature urban compost as the amendment maybe recommended as an effective method for TPH remediation.
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http://dx.doi.org/10.1186/s40201-017-0267-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5327614PMC
February 2017

A new bioindicator, shell of , and sediment samples to monitors metals (Al, Zn, Fe, Mn, Ni, V, Co, Cr and Cu) in marine environment: The Persian Gulf as a case.

J Environ Health Sci Eng 2016 10;14:16. Epub 2016 Oct 10.

Ecology Department, Iranian Shrimp Research Institute, Bushehr, Iran.

Background: The present work was designed to detect heavy metal contents of Al, Zn, Fe, Mn, Ni, V, Co, Cr and Cu in sediments and shells of the collected in polluted and unpolluted areas along the Persian Gulf.

Methods: The samples were taken from surface sediments (0-10 cm) and shells of in two separated areas (polluted and unpolluted) in northern part of the Persian Gulf, Asaluyeh Bay, during summer 2013. The prepared samples were analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES).

Results: Based on the results, all measured metals including Al, Zn, Fe, Mn, Ni, V, Co, Cr and Cu were meaningfully higher in the sediment samples of polluted area compared to unpolluted area and the order of metal concentrations in the sediment samples were Cr > Co > V > Ni > Zn > Cu > Fe > Al > Mn in polluted area. In the case of shell samples of , polluted area contained significantly higher contents of Al, Zn, Fe, Mn, Ni, Co, Cr and Cu compared to unpolluted area and the order of metal concentrations in the shell samples were Fe > Zn > Al > Mn > Cu > Cr > Ni > Co in the polluted area.

Conclusion: It was concluded that shells of the can be used as a suitable bioindicator for heavy metals in the aquatic environment. Results confirmed that due to the possible contaminations by oil and gas activities near the polluted area perennial monitoring and mitigation measures is extremely necessary.
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http://dx.doi.org/10.1186/s40201-016-0260-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5057424PMC
October 2016