Publications by authors named "Ramin Nabizadeh Nodehi"

42 Publications

Monitoring of caffeine concentration in infused tea, human urine, domestic wastewater and different water resources in southeast of Iran- caffeine an alternative indicator for contamination of human origin.

J Environ Manage 2021 Apr 19;283:111971. Epub 2021 Jan 19.

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

The present study was developed to evaluate the caffeine concentration in commercially high-consumed brands of dry black tea, urine of tea consumers, raw and treated wastewater, as well as water resources (WRs) in Zabol city, Iran. Furthermore, a complementary analysis was performed to evaluate the relationship between caffeine content and total coliform (TCF) and Escherichia coli (E. coli) in water sources. In this end, tea (90 samples), urine (90 samples), raw sewage (72 samples), treated sewage (72 samples), and septic tank sewage (36samples) were taken from Zabol city and analyzed in terms of caffeine content. To evaluate the correlation between caffeine and TCF and E. coli, 102 water samples were taken from WRs in Zabol city. Caffeine was measured by high-performance liquid chromatography (HPLC). Furthermore, TFC and E. coli were measured based on the procedure outlined by standard methods for water and wastewater examination and the most probable number (MPN) method. The results indicated that the caffeine concentration in different tea brands consumed by Zabol people were in the range of 12.35-18.75 mg/L. The mean caffeine level in the male group' urine (7.08 ± 1.00 μg/mL) was significantly higher than the female group (4.83 ± 1.94 μg/mL). The results showed that the total average amount of caffeine in raw and treated wastewater in Zabol city was 21.04 ± 2.22 and 19.86 ± 2.08 μg/L, respectively. Besides, the caffeine removal efficiency by the Zabol wastewater treatment plant (ZWTP) was found to be between 4.79 and 51.39%. According to the results, the environmental risk associated with caffeine through the discharge of raw and treated wastewater from ZWTP into receiving WRs was estimated to be less than the allowable limit (RQ = 1). The results showed that caffeine could be an indicator for fecal contamination with human origin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvman.2021.111971DOI Listing
April 2021

Iranian population exposures to heavy metals, PAHs, and pesticides and their intake routes: a study protocol of a national population health survey.

Environ Sci Pollut Res Int 2021 Apr 4;28(13):16744-16753. Epub 2021 Jan 4.

Non-Communicable Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

Cancer is the second leading cause of death in the world and the third leading cause of death in Iran. It has been proven that numerous cancer cases are caused by exposure to environmental pollutants. There is a public health concern regarding an increase in exposure to carcinogens across Iran through different sources (air, food, and water) and a lack of research to address this issue. This study aims to gather data on exposure to heavy metals, polycyclic aromatic hydrocarbons (PAHs), and pesticides and their intake routes during the implementation of a national population health survey. This is a cross-sectional study of environmental pollutants in Iran, with a stratified multi-stage random sampling method, which led to 660 nationally representative samples in 132 clusters in three sequential parts. The first will be questionnaires to obtain demographics, assets, food records, air quality, and food frequency. The second will be physical measurements, including anthropometric and body composition. The third will be lab assessments that measure 26 types of environmental pollutants (7 heavy metals, 16 PAHs, and 3 pesticides) in urine, inhaled air, and consumed food and water of the population under study using ICP-MS and GS-MS devices. The results of this study will inform policymakers and the general population regarding the level of threat and will provide evidence for the development of interventional and observatory plans on the reduction of exposures to these pollutants. It could also be used to develop local standards to control contaminants through the three exposure routes. This study protocol will obtain data needed for policymakers to set surveillance systems for these pollutants at the national and provincial level to address the public concerns regarding the contamination of food, air, and water.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-020-12004-3DOI Listing
April 2021

Human health and ecological risk assessment of heavy metal(loid)s in agricultural soils of rural areas: A case study in Kurdistan Province, Iran.

J Environ Health Sci Eng 2020 Dec 8;18(2):469-481. Epub 2020 May 8.

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

Background: Agricultural soils pollution with heavy metal (loid) s (HMs) can create significant ecological and health problems. The aims of present study were to characterize HMs pollution profile of dry farmland soils in rural areas of Kurdistan province in Iran and evaluate potential associated ecological and health risks.

Methods: Different indices of Geo-accumulation index (I), Individual contamination factor (ICF), Nemerow composite pollution index (NCPI) and Potential Ecological Risk Index (PERI) were employed to assess the bio-accumulation of the HMs and evaluate associated ecological risks. Human health risks estimated with total hazard index (THI) and total carcinogenic risk (TCR) indices based on ingestion, inhalation and dermal exposure pathways for children and adults.

Results: As, Cd, Cr, Ni and Pb exceeded the soil standards. The spatial maps of the I showed that As pollution was at severe level in eastern part of the study region. According to the ICF results, the studied soils were extremely contaminated with As, Cd, Cr, Ni and Zn. Furthermore, based on the pollution indices, some of sampling sites were critically polluted by abovementioned HMs. For children and adults groups, the THI values in 13 and 97% of sampling sites were more than 1 and the TCR in 7 and 14% of sampling sites were more than 10, respectively. The farmland soil pollution of the study area by As and Cr were found to be quite serious and dangerous.

Conclusion: The findings of this study suggest that further attention should be paid by decision-makers to control the HMs pollution in the agricultural soils of the study area.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40201-020-00475-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721949PMC
December 2020

A Comparative Survey on Antioxidant Activity of Iranian Shrimp Waste [Penaeus Semisulcatus] and Synthetic Antioxidants.

Curr Drug Discov Technol 2020 Oct 6. Epub 2020 Oct 6.

Division of Food Safety and Hygiene, Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran,. Iran.

Shrimp waste, as an important source of natural carotenoids, is produced in large quantities in seafood processing industry. One of the important characteristics of carotenoids is their ability to act as antioxidants, thus protecting cells and tissues from damaging effects of free radicals and singlet oxygen. The aim of this study was to find effective method for carotenoid extraction [Enzymatic and alkaline treatment] from shrimp waste and compare their antioxidant potential with synthetic antioxidants butylated hydroxyanisole [BHA] and butylated hydroxytoluene [BHT] using sunflower oil. The sunflower oil was exposed to three concentration of extracted carotenoid [470, 235 and 118 mg/kg] and synthetic antioxidants. The inhibition of lipid peroxidation was evaluated for Malondialdehyde and peroxide value. The mean values of carotenoid extract were 243 and 170 mg/kg for enzymatic and alkaline treatment, respectively. So the highest efficacy of carotenoid extraction was obtained from enzymatic extraction. The oil samples containing 470 ppm carotenoid, which extracted by alcalase as the default treatment, exhibited the less peroxide value and higher antioxidant potential than the oil samples containing synthetic antioxidants. According to the results, the synthetic antioxidants can be replaced by extracted carotenoids from shrimp waste as a natural antioxidant to inhibit oxidation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2174/1570163817999201006192141DOI Listing
October 2020

The concentration of BTEX compounds and health risk assessment in municipal solid waste facilities and urban areas.

Environ Res 2020 12 23;191:110068. Epub 2020 Aug 23.

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

In this study, human exposure to benzene, toluene, ethylbenzene, xylenes (BTEX), along with their respective risk assessment is studied in four major units (n = 14-point sources) of the largest municipal solid waste management facilities (MSWF) in Iran. The results were compared with four urban sites in Tehran, capital of Iran. Workers at the pre-processing unit are exposed to the highest total BTEX (151 μg m). In specific, they were exposed to benzene concentrations of 11 μg m. Moreover, the total BTEX (t-BTEX) concentrations measured over the conveyor belt was 198 μg m at most, followed by trommel (104), and active landfills (43). The mean concentration of ambient t-BTEX in Tehran is 100 μg m. On average, xylenes and toluene have the highest concentrations in both on-site and urban environments, with mean values of 24 and 21, and 41 and 37 μg m, respectively. Even though the non-carcinogenic risk of occupational exposure is negligible, BTEX is likely to increase the chance of carcinogenic risks (1.7E-05) for workers at the pre-processing unit. A definite carcinogenic risk of 1.3E-04, and non-carcinogenic effect, of HI = 1.6 were observed in one urban site. With the exception of the pre-processing unit, the citizens of Tehran had higher exposure to BTEX. Overall, BTEX concentrations in the largest MSWF of Iran remains an issue of public health concern.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2020.110068DOI Listing
December 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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41370-020-0222-6DOI Listing
July 2020

Prenatal urinary concentrations of environmental phenols and birth outcomes in the mother-infant pairs of Tehran Environment and Neurodevelopmental Disorders (TEND) cohort study.

Environ Res 2020 05 2;184:109331. Epub 2020 Mar 2.

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

Daily exposure to environmental phenols can lead to potential undesirable effects on the health of pregnant women and fetuses. The present study is aimed to evaluate the relationship between maternal urinary concentrations of phenols in pregnancy and anthropometric birth outcomes. The studied population comprised of 189 pregnant women participating in the Tehran Environment and Neurodevelopmental Disorders (TEND) prospective cohort study, which had been ongoing since March 2016 in some hospitals and health care delivery centers in Tehran, Iran. Concentrations of bisphenol-A, triclosan, 4-nonylphenol, and parabens were determined in spot urine samples of pregnant mothers in the first trimester. Weight, length, and head circumference at birth were also extracted from the mothers' delivery files. Multivariable linear regression was used to examine the relationship between log-concentrations of phenols and birth outcomes. When we analyzed all samples regardless of neonates' gender, none of the urinary concentrations of phenols were associated with weight and length at birth. Indeed, in sex-stratified adjusted models, one log-unit increase of butylparaben was related to a 283.6 g (95% CI: 23, 544) increase in boys' birth weight. Prenatal urinary concentration of triclosan and propylparaben was respectively related to a decrease of 4.8 cm (95% C: -8.5, -1.1) in boys' length and 0.9 cm (95%CI: -1.8, -0.04) in girls' length. In the adjusted models for estimating the changes in head circumference, one log-unit increase of triclosan, methylparaben, and butylparaben led to a reduction of 1.6 cm (95% CI: -3.17, 0.03), increase of 0.8 cm (95% CI: -0.01, 1.6) and 0.7 cm (95% CI: 0.08, 1.4) in head circumference at birth respectively. Our results suggested that prenatal triclosan and parabens exposure might be associated with head circumference at birth. Furthermore, we observed a sexually dimorphic pattern between maternal triclosan and parabens exposure during pregnancy and fetal growth. However, these findings must be interpreted while taking into account the limitations of this study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2020.109331DOI Listing
May 2020

Serum level of PCBs and OCPs and leukocyte telomere length among adults in Tehran, Iran.

Chemosphere 2020 Jun 1;248:126092. Epub 2020 Feb 1.

Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Enghelab St., Tehran, Iran; Department of Research Methodology and Data Analysis, Institute for Environmental Research (IER), Tehran University of Medical Sciences, Kargar St., Enghelab Sq., Tehran, Iran.

Exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) may change leukocyte telomere length (TL) at the end of the DNA sequence. The purpose of this study was to investigate the association between PCBs and OCPs exposure with TL in Tehran adult males. Whole-blood samples were randomly taken from three hundred adult males in population-based cross-section study from October 2016 to November 2017. We studied the serum levels of PCBs, OCPs as well as socio-demographic characteristics of individuals. The quantitative PCR was used to investigate the number of the telomere (T) repeats to the number of a single copy gene. We measured the effect of each PCBs and OCPs congeners on TL using linear regressions adjusted for age, BMI, smoking, and dietary patterns. The median level of the six non-dioxin-likes, five dioxin-likes PCBs three OCPs and TL in the study population were 344.5, 306.0, 45.0 ng/g lipid and 5377.7 ± 573.4 base pairs, respectively. In the adjusted model, the percent difference in the TLs with exposure to Σnon-dioxin-like PCBs, Σdioxin-like PCBs, and OCPs were 1.93 (-0.70 to 5.4), 3.4 (1.8-8.3) and -2.4 (-0.80 to -6.2), respectively. In the fourth quartile compared to the first quartile, the percent difference in the TLs due to Σnon-dioxin-like PCBs, Σdioxin-like PCBs, and OCP exposure were 0.01 (-0.01 to 0.05), 10.3 (2.9-18.1) and -0.20 (-0.10 to -4.5), respectively. Exposures to ndl-PCBs and dl-PCBs (except for PCB28) were related to longer TLs, but OCPs exposure can be related to telomere shortening.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2020.126092DOI Listing
June 2020

Correction to: Chemical composition of PM10 and its effect on in vitro hemolysis.

J Environ Health Sci Eng 2019 Jun 22;17(1):503-504. Epub 2019 Mar 22.

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

[This corrects the article DOI: 10.1007/s40201-018-00327-w.].
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40201-019-00360-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582202PMC
June 2019

Developing environmental health indicators [EHIs] for Iran based on the causal effect model.

J Environ Health Sci Eng 2019 Jun 27;17(1):273-279. Epub 2019 May 27.

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

Background: Environmental health monitoring and its effects on health are very important in health systems. Relationship between environment and health can be done by simplifying data in understandable indicators for people and policy-makers. The present study presents the general framework for formulating environmental health quality index for Iran.

Methods: This study was implemented through expert panel at two levels: indicator domain determination and domain specific variables selection. Domain specific variables were selected based on the Driving force-Pressure-State-Exposure-Effect-Action (DPSEEA) framework from the list of national and international variables.

Results: Seven environmental health issues [air quality, drinking water, sewage disposal, food, radiation management and housing and human settlements] were determined, and three variables were selected for air quality, 8 variables for water quality, 5 variables for sanitation, 1 variable for food quality, 3 variables for housing and human settlements, 4 variables for solid waste management and 3 variables for radiation management.

Conclusions: Environmental health indicators determination based on the causal effect model leads to a better understanding of the relationship between the environment and health by simplifying data in an understandable format for public and improves prioritization of policy-making in the environmental health. In this study, environmental health indicators for Iran were proposed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40201-019-00346-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582035PMC
June 2019

Optimizing the performance of conventional water treatment system using quantitative microbial risk assessment, Tehran, Iran.

Water Res 2019 Oct 1;162:394-408. Epub 2019 Jul 1.

Water and Wastewater Company, Department of Water and Wastewater Quality Control Laboratory, Tehran, Iran.

The performance of conventional drinking water treatment plants (WTPs) can be improved using quantitative microbial risk assessment (QMRA). A QMRA study on Cryptosporidium using actual pathogen density was conducted to examine the performance of Jalaliyeh WTP in Tehran, Iran. The infection risk and the burden of disease attributed to the parasite presence in finished water were estimated incorporating physical and chemical log reduction values (LRVs), using stochastic modeling and disinfection profiling. The risk and burden of disease were compared with health-based targets, i.e. one case of infection per 10,000 people or 10 DALYs per person per year. The parasite's LRVs were 2.31 and 0.034 log provided by physico-chemical treatment and disinfection processes, respectively. The mean of estimated risk (111 cases per 10 people per year) and the burden of disease (11.7 DALYs per 10 people per year) both exceeded the targets. To control the excess risk, three QMRA-based disinfection scenarios were examined including: (1) employing chlorine dioxide (ClO) instead of chlorine (2) ozonation with a concentration of 0.75 mg/L (Ct = 22.5 min mg/L) and (3) UV irradiation with a dose of 10 mJ/cm. The LRV of parasite may be increased to 3.0, 5.1 and 4.9 log by employing ClO, ozonation and UV irradiation, respectively. The use of ozone or UV as alternative disinfectants, could enhance the disinfection efficacy and provide sufficient additional treatment against the excess risk of parasite. QMRA could make it easier applying appropriate improvement to conventional WTPs in order to increase the system performance in terms of health-based measures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.watres.2019.06.076DOI Listing
October 2019

Chemical composition of PM and its effect on in vitro hemolysis of human red blood cells (RBCs): a comparison study during dust storm and inversion.

J Environ Health Sci Eng 2019 Jun 2;17(1):493-502. Epub 2019 Feb 2.

1School of Public Health, Tehran University of Medical Sciences, Enqelab Square, Tehran, Iran.

Purpose: This study aimed to investigate chemical composition of PM (particulate matter with aerodynamic diameter ≤ 10 μm) during dust storm and inversion in Tehran and hemolysis effects.

Methods: PM was sampled in Tehran, Iran, during dust storm and inversion conditions. Water soluble ions (F¯, Cl¯, NO¯, NO¯, SO¯, Na, K, NH, Ca, Mg) and elements (Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sn, Sr, V, Zn, Pt, Rh, Pd, As and Si) were analyzed by ion chromatograph (IC) and inductively coupled plasma optical emission spectrometer (ICP-OES), respectively. Hemolysis was examined as in vitro at PM concentrations of 50-300 μg/ml.

Results: Daily average of PM concentrations in dusty and inversion days were 348.40 and 220.54 μg/m, respectively. Most prevalence ionic components were NO¯, Cl¯, SO¯ and Ca during dust storm and SO¯, NO¯, Cl¯ and NH during inversion. Si, Fe and Al had the maximum values in both conditions. Particles associated with both conditions induced hemolytic responses. PM from dusty day showed a higher hemolysis percent (10.24 ± 4.67%) than inversion (9.08 ± 5.47%), but this difference was not significant ( = 0.32). Hemolytic effects were significantly intensified by increased PM concentrations ( < 0.001) in a dose-response manner.

Conclusions: As the results, chemical composition of sampled particles from inversion days and dust storm was different from each other. Hemolytic effects of particles during dust storm were more than inversion days. However, this difference was not statistically significant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40201-018-00327-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582044PMC
June 2019

Propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR) assay for rapid detection of viable and viable but non-culturable (VBNC) in swimming pools.

J Environ Health Sci Eng 2019 Jun 7;17(1):407-416. Epub 2019 Mar 7.

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

Lack of culturability in the viable but non-culturable (VBNC) bacteria and the ability to regain infectivity in favourable conditions is one of the new challenges of public health providers for monitoring in environmental samples. Propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) is one of the promising methods for timely detection of VBNC pathogens in environmental samples. We developed and used a method for the first time to detection of VBNC in swimming pool water samples using a membrane filter (MF). Moreover, the dominant model of the distribution of colonies on the MF and the effect of the culture medium and MF type on colony recovery by MF were evaluated. Swimming pool samples were subjected to conventional culture-based, qPCR and PMA-qPCR methods and the results were compared for the presence of VBNC in the samples. The positivity rate was 21% and 75% for in water samples as confirmed by standard culture-based and qPCR methods, respectively. Furthermore, of 24 samples, 9 (37.5%) were positive for VBNC . The developed qPCR/PMA-qPCR assay can detect the VBNC bacteria directly from aquatic samples and may result in better monitoring of recreational waters.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40201-019-00359-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582174PMC
June 2019

Landfill site selection using a hybrid system of AHP-Fuzzy in GIS environment: A case study in Shiraz city, Iran.

MethodsX 2019 14;6:1454-1466. Epub 2019 Jun 14.

Department of Natural Resources, School of Environmental Sciences, Tehran University, Tehran, Islamic Republic of Iran.

Landfilling with simplicity and economic advantages is the most common element for waste management in both developed and developing countries. Landfill site selection in a proper way is an important municipal planning process which prevent environmental issues including water pollution imposed for insanitary landfills. The present research was developed to exhibit a simplified method of multi criteria decision making (MCDM) and Fuzzy memberships in GIS environment to ascertain best landfill sites for Shiraz county, located south of Iran. 15 most common sub-criteria, documented in literature and implicated by Iranian environmental protection organization (IEPO) including surface water, ground water, land use, distance to well, soil type, slope, protected area, fault in environmental group, residential area, road, airport, village, infrastructure, historical area, wind direction in socio-economical group were selected and the weight of each criterion was determined based on expert's knowledge with use of analytical hierarchy process (AHP). The results of the present research are as follows: •Distance to residential area and groundwaters with weight of 0.36 and 0.28 were recognized as the most important criteria for landfill site selection.•The six suitable areas for landfill in Shiraz county is 1.003% of total area equal to 8710 ha.•AHP and Fuzzy memberships has a great potential and ability for landfill site selection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mex.2019.06.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6593174PMC
June 2019

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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2019.125126DOI Listing
November 2019

Determining additional risk of carcinogenicity and non-carcinogenicity of heavy metals (lead and arsenic) in raw and as-consumed samples of imported rice in Tehran, Iran.

Environ Sci Pollut Res Int 2019 Aug 21;26(23):24190-24197. Epub 2019 Jun 21.

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

Rice is considered the most main food in Iranian diet. Its chemical contamination with heavy metals can lead to adverse effects to human health. In the present study, 60 imported rice samples from 20 different brands were collected and examined in terms of lead and arsenic levels in Tehran. Besides, point estimation and uncertainty analysis were used to determine the additional risk of carcinogenicity and non-carcinogenicity in raw and as-consumed rice. The results showed that the means of lead and arsenic (mg/kg fresh weight) in raw sampled rice were 0.0352 ± 0.0398 and 0.106 ± 0.049, respectively, and they were 0.0226 ± 0.0360 and 0.0689 ± 0.046 in as-consumed rice, respectively. Additionally, lead and arsenic amounts were 5% and 15% higher than the value set by Institute of Standards and Industrial Research of Iran respectively, while assessment of the non-carcinogenicity risk of lead and arsenic in point estimation and uncertainty analysis showed the hazard quotient and hazard index values were less than 1 and in safe ranges in both raw and as-consumed rice and were not considered a threat to the public health. The additional risk of arsenic carcinogenicity in point estimation and uncertainty analysis in raw and as-consumed rice samples found higher than the 1E-06 EPA's acceptable level of risk. So, these results could be applicable and encourage researchers to perform more detailed studies with more samples for considering by food authorities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-019-05778-8DOI Listing
August 2019

Real-time polymerase chain reaction assays for rapid detection and virulence evaluation of the environmental Pseudomonas aeruginosa isolates.

Mol Biol Rep 2019 Aug 15;46(4):4049-4061. Epub 2019 May 15.

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

Rapid and species-specific detection, and virulence evaluation of opportunistic pathogens such as Pseudomonas aeruginosa, are issues that increasingly has attracted the attention of public health authorities. A set of primers and hydrolysis probe was designed based on one of the P. aeruginosa housekeeping genes, gyrB, and its specificity and sensitivity was evaluated by TaqMan qPCR methods. The end point PCR and SYBR Green qPCR were used as control methods. Furthermore, multiplex RT-qPCRs were developed for gyrB as reference and four virulence genes, including lasB, lasR, rhlR and toxA. Totally, 40 environmental samples, two clinical isolates from CF patients, two standard strains of P. aeruginosa, and 15 non-target reference strains were used to test the sensitivity and specificity of qPCR assays. In silico and in vitro cross-species testing confirmed the high specificity and low cross-species amplification of the designed gyrB418F/gyrB490R/gyrB444P. The sensitivity of both TaqMan and SYBR Green qPCRs was 100% for all target P. aeruginosa, and the detected count of bacteria was below ten genomic equivalents. The lowest M value obtained from gene-stability measurement was 0.19 that confirmed the suitability of gyrB as the reference gene for RT-qPCR. The developed qPCRs have enough detection power for identification of P. aeruginosa in environmental samples including clean and recreational water, treated and untreated sewage and soil. The short amplicon length of our designed primers and probes, alongside with a low M value, make it as a proper methodology for RT-qPCR in virulence genes expression assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11033-019-04855-yDOI Listing
August 2019

Prenatal exposure to parabens and anthropometric birth outcomes: A systematic review.

Environ Res 2019 06 12;173:419-431. Epub 2019 Mar 12.

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

Parabens are ubiquitous substances commonly used as preservatives because of their antibacterial activity. The estrogenic activity of parabens may cause undesirable health effects and adverse birth outcomes. The objective of the present systematic review was to investigate the association between prenatal exposure to parabens and anthropometric birth outcomes. PubMed, Web of Science, Scopus, and Embase databases were systematically searched until April 18, 2018. Of 326 records that remained after removing duplicates, 6 original articles were included in the final analysis after excluding irrelevant articles. The included studies indicated that most of the pregnant mothers were exposed to parabens, especially methyl and propyl parabens. However, no definitive association was found between the prenatal urinary concentration of parabens and birth weight or head circumference. In addition, a positive but non-significant association was detected between birth length and maternal exposure to parabens. The present systematic review revealed that assessment of significant associations in current epidemiological studies is impermissible due to methodological limitations and absence of inter-study consistency. Furthermore, because of the complexity of the effect of environmental factors on health, future large-scale studies with proper study design are required to investigate the effect of parabens exposure on birth outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2019.02.044DOI Listing
June 2019

A systematic literature review for some toxic metals in widely consumed rice types (domestic and imported) in Iran: Human health risk assessment, uncertainty and sensitivity analysis.

Ecotoxicol Environ Saf 2019 Jul 25;176:64-75. Epub 2019 Mar 25.

Research Center for Environmental Determinants of Health (RCEDH), Kermanshah University of Medical Sciences, Kermanshah, Iran.

In present study we aimed to investigate the literature in the form of systematic review to determinate the concentrations of some toxic metals (arsenic, lead, and cadmium) in widely consumed rice brands in Iran and their related health risks. International and Iranian national databases were searched carefully with appropriate keywords for papers on toxic metal contamination of rice from Agust-2000 to Agust-2018. Initially, 560 articles were found, of which only the 50 papers fit the inclusion criteria and were selected for further analysis. The Monte Carlo Simulation was applied to generate missing data (mean, standard deviation, data distribution and sample size) of toxic metal concentration in some papers. Then, statistical analysis, health risk assessment, and uncertainty and sensitivity analysis were performed. The results indicated that approximately 88% of rice consumed in Iran (including Iranian, Pakistani and Indian rice) do not meet the national standard and WHO/FAO guideline requirements and their related health risks are unacceptable. The risks of arsenic and lead in Indian rice and cadmium in Iranian rice were considerably higher than others. In conclusion, according to our findings, In conclusion, it is necessary to prevent toxic metals contamination of rice by modifying cultivation patterns and, also, prevent low-quality rice brands to be imported.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2019.03.072DOI Listing
July 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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2019.03.056DOI Listing
July 2019

An in vitro method to evaluate hemolysis of human red blood cells (RBCs) treated by airborne particulate matter (PM).

MethodsX 2019 10;6:156-161. Epub 2019 Jan 10.

Environmental Health Engineering Research Center, Kerman University of Medical Sciences, Kerman, Iran.

Air pollutants are capable to enter bloodstream through the nose, mouth, skin and the digestive tract. Hemolysis is the premature destruction of red blood cells (RBCs) membranes. This can affect metabolism of RBCs and reduce cell life. Each of these adverse effects could lead to anemia, jaundice and other pathological conditions. Hemolysis can induce by the mineral components adsorbed on the particles. The aim of this study was to evaluate hemolysis of RBCs treated by airborne PM (PM with aerodynamic diameter ≤ 10 μm) in vitro. Study had two main stages including sampling and preparation of PM suspension, and hemolysis test. Particle samples were collected by means of a high-volume sampler on fiberglass filters. The PM was extracted through dry ultrasonic method. Blood sample was incubated by PM at concentrations 50-300 μg/mL for 3 h. Hemolysis percent was assessed through measurement of Hemoglobin concentration in test samples and total blood hemoglobin (TBH) sample by the cyanmethemoglobin method. Analysis of variance (ANOVA) and Tukey post-hoc test were applied to compare mean values of hemolysis percent between different PM concentrations. Method used in current study is suggested for investigation of toxic effects of airborne particle matter (PM, PM and PM) on human RBCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mex.2019.01.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6355395PMC
January 2019

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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2018.12.060DOI Listing
May 2019

Public ingestion exposure to Ra in Ramsar, Iran.

J Environ Radioact 2019 Mar 17;198:11-17. Epub 2018 Dec 17.

Department of Medical Physics, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address:

Ramsar, in the north of Iran by the Caspian Sea, has been known for the highest natural radiation background on Earth due to the local geology and hydrogeology. The residents and visitors use the hot springs that distribute the natural radionuclides especially Ra and its decay products in the areas. Many studies have been undertaken to measure the absorbed dose rate in Ramsar's air, however, no survey has been done to assess public internal exposure from ingestion of natural radionuclides, such as, a broad survey for Ra was conducted in foodstuffs and drinking water. This study presents the results of public annual activity intake (Bq) and effective dose (μSv) from ingestion of Ra in foodstuffs and drinking water in Ramsar city. The total mean annual intake for adults was found to be 24.8 Bq. The annual average effective dose due to ingestion exposure to Ra was found to be 6.9 μSv for adults that were slightly more than the estimated global averages reported by UNSCEAR, 2000 (6.3 μSv). The contribution of drinking water and foodstuffs represent respectively about 30% and 70% of the total mean annual effective dose due to Ra. The highest effective dose from ingestion of Ra for adults was estimated to be 80.6 μSv y. Based on the results of this study, even with the largest Ra value in our survey, maximum annual effective dose due to consumption of foodstuffs and drinking water for children was 164.2 μ b Sv y.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvrad.2018.11.016DOI Listing
March 2019

Association Among Sources Exposure of Cadmium in the Adult Non-smoking General Population of Tehran.

Biol Trace Elem Res 2019 Sep 7;191(1):27-33. Epub 2018 Dec 7.

Center for research on occupational disease, Tehran University of Medical Sciences, Tehran, Iran.

Acute and chronic exposure to cadmium can cause numerous health effects including poisoning, as well as, bone, liver, and kidney diseases. Cadmium competes with iron absorption in blood and can induce anemia. Cadmium body burden can be measured through urine and blood samples. Urine reflects chronic and blood indicates recent and cumulative exposures to cadmium. Dietary is considered as the main source of exposure to cadmium in non-smoking general population. The study was conducted to determine cadmium level in blood, urine, and in diet of 120 non-smoking adults in Tehran. Dietary components and consumption pattern of participants estimated by a food frequency questionnaire. Next, the correlation investigated between them. Moreover, serum ferritin measured as a marker of iron storage in blood to determine its association with cadmium. The prediction of cadmium fate in the body is determined by toxicokinetic models. This study tried to evaluate one of these models' validity which is developed to predict urinary cadmium from dietary. Afterwards, the predicted urinary compared with the measured urinary cadmium. The correlation coefficient between dietary and blood cadmium equaled 0.66 which was statically significant, but the correlation between dietary and urinary cadmium was minimal and not statically significant (p > 0.05). An inverse and negative correlation was found between serum ferritin and blood cadmium. The mean predicted urinary cadmium calculated by the model was 2.5-fold higher than the measured value in the total population. Results of the present study revealed that blood cadmium reflected mainly acute exposure. There was no correlation between chronic and acute exposures to cadmium. The low serum ferritin level increased cadmium amount in blood. Moreover, the mean predicted urinary cadmium by the model was greater than the measured value. It can because of characteristics of populations and type of dietary exposure. Thus, it is suggested that the model coefficients are determined in each society based on their characteristics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12011-018-1590-9DOI Listing
September 2019

An in vitro method to survey DNA methylation in peripheral blood mononuclear cells (PBMCs) treated by airborne particulate matter (PM).

MethodsX 2018 17;5:1508-1514. Epub 2018 Nov 17.

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

The International Agency for Research on Cancer (IARC) has defined outdoor air pollution and PM as the human carcinogen (Group 1), which mainly cause an increased risk of lung cancer. Scientists have considered epigenetic modifications as a possible mechanism to deal with adverse effects of air pollution. This study aimed to compare the effect of airborne PM (PM with aerodynamic diameter ≤10 μm) on in vitro global methylation in human peripheral blood mononuclear cells (PBMCs). PM was sampled in metropolitan Tehran, the capital of Iran. PBMCs were extracted from whole blood of healthy males and treated with PM suspension at concentrations of 50-300 μg/mL for 4 h. Untreated cells were used as the negative control. Genomic DNA was extracted from each sample using the DNA blood mini kit according to the manufacturer's instruction. Moreover, 5-methylsytosine (%5-mC) and 5-hydroxymethylcytosine (%5-hmC) were measured by the enzyme-linked immunosorbent assay (ELISA) method. %5-mC and %5-hmC in each sample was compared with negative control and reported as difference %5-mC and %5-hmC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mex.2018.11.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6260300PMC
November 2018

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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2018.10.090DOI Listing
March 2019

Short-term effects of particle size fractions on lung function of late adolescents.

Environ Sci Pollut Res Int 2018 Aug 23;25(22):21822-21832. Epub 2018 May 23.

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

Although ambient air pollution has been linked to reduced lung function in healthy students, longitudinal studies that compare the response of asthmatic and healthy adolescents are lacking. To evaluate lung function responses to short-term ambient air particulate matter (PM, PM, and PM) levels, we conducted a study on high school students aged 15-18 years. The aim of this study was to assess effects of acute exposure to ambient air particulate matter (PM) on lung function in healthy and asthmatic late adolescents. We examined associations of lung function indices and ambient PM levels in 23 asthmatic and 23 healthy students. Paired-samples T test was used to evaluate the association of exposure to airborne PM concentrations with lung function test results (FVC, FEV, FEV/FVC, and FEF). We observed negative impact of exposure to an increased concentration of ambient air PM, PM, and PM on lung function parameters of asthmatic and healthy late adolescents. These findings are consistent with other similar short-term studies which have confirmed the adverse effect of PM air pollution. These associations were stronger in asthmatic subjects compared with those in healthy ones. There are significant adverse effects of ambient air PM on pulmonary function of adolescents, especially asthmatics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-018-2264-zDOI Listing
August 2018

What do we know about exposure of Iranians to cadmium? Findings from a systematic review.

Environ Sci Pollut Res Int 2018 Jan 19;25(2):1-11. Epub 2017 Dec 19.

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

Cadmium is an important environmental contaminant. High consumption of chemical fertilizers and industrial activities in recent decades has caused people to be worried about exposure to cadmium. There is no policy for environmental and biological monitoring of exposure to cadmium in the general population in Iran. This study was aimed to review cadmium content in consuming foods and biological samples in Iran, systematically. We developed a comprehensive search strategy and used it to search on Web of Science, Scopus, Science Direct, and Scientific Information Database until 28 December 2016. The totals of 285 articles were identified and finally 31 original papers were selected. Cadmium contamination was found in Iranian food groups such as rice, cereal and legumes, canned tuna fish, vegetables, fruit juice, and egg. This study showed that cadmium amount in 75% of the consumed rice samples (domestic and imported) was higher than the maximum limits approved by institute of standards and industrial research of Iran. Lettuce samples in Yazd were recorded the highest concentration of cadmium compared to other studies. In addition, high amount of cadmium was observed in the blood of the general population. Regarding the cadmium contamination in food and blood samples in Iran, policies must be adopted to reduce exposure to cadmium through different matrices as much as possible.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-017-0863-8DOI Listing
January 2018

Prevalence of asthma and associated factors among male late adolescents in Tabriz, Iran.

Environ Sci Pollut Res Int 2018 Jan 8;25(3):2184-2193. Epub 2017 Nov 8.

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

Asthma is an important chronic disease all over the world. The aim of this study was to determine the prevalence of asthma in a population of male late adolescents and its association with some contributing risk factors in northwest of Iran. This cross-sectional study was carried out in selected high schools of Tabriz, Iran, in 2016. The asthma prevalence and patient background information were examined using a questionnaire that prepared by the ISAAC. One hundred forty-two out of 1134 subjects (12.4%) identified to have asthma, 23.3% had history of current wheeze, and 16.3% had wheezing in the previous year. Family history of asthma was present in 17.1% of the participants; prevalence of active smoking in the study subjects was 3.1%; 25.1% of all subjects had exposure to secondhand tobacco smoke and keeping pets at home was present in 9.1%. Excess weight (overweight and obesity) was positively associated with prevalence of asthma (p < 0.001). No statistically significant associations were observed between asthma and father's education level (p = 0.570), mother's education level (p = 0.584), type of birth subjects (p = 0.571), and time spent outdoors during a full day (p = 0.863). Our results suggest that family history of asthma and atopy, exposure to secondhand tobacco smoke, active smoking, amount of automobile traffic around subjects' home, and keeping pets at homes are important risk factors for asthma, while time spent outdoors, educations of parents, and delivery type (normal vaginal delivery vs. C-section) subjects are not. Therefore, decreased of exposure to some environmental risk factors could be effective to reduce rate of the prevalence of asthma and wheeze.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-017-0553-6DOI Listing
January 2018

Catalytic decomposition of 2-chlorophenol using an ultrasonic-assisted FeO-TiO@MWCNT system: Influence factors, pathway and mechanism study.

J Colloid Interface Sci 2018 Feb 12;512:172-189. Epub 2017 Oct 12.

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

As a reusable sonocatalyst, magnetically separable FeO-TiO@MWCNT (FMT) was synthesized by an ultrasound-assisted wet impregnation method and was evaluated in the removal of 2-chlorophenol (2CP). Physical and chemical properties of the catalyst composite materials were investigated by all catalysts were systematically characterized using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Analysis (EDX), Dynamic light scattering (DLS), and N-physisorption. The efficiency and kinetics of 2CP removal by FMT-assisted sonocatalysis (FMT-US) was systematically investigated under various operational parameters i.e. pH, FMT and 2CP concentration, temperature and ultrasonic power. The results indicated that 0.4gL FMT dosage, pH 5, temperature of 35°C as well as 50 w ultrasound power are the most favorable conditions for the degradation of the 2CP. Furthermore, both of the superoxide and hydroxyl radicals were produced in the reaction, however, superoxide radicals were assumed to be the dominating reactive species for the 2CP degradation, according to the scavenging tests and electron paramagnetic resonance tests. Moreover, the FMT catalyst exhibited a high reusability and stability in the US/FMT system during the five repetitive experiments. The intermediate products were identified by GC-MS, thereby a possible degradation pathway is proposed. The chemical oxygen demand (COD) and corresponding total organic carbon (TOC) removal efficiencies were 64.9% and 56.7%, respectively. Finally, toxicity tests showed that the toxicity of the solution increased during the first 5min and then decreased significantly with the progress of the oxidation. The mechanisms of ultrasound irritation enhanced FMT activation were also proposed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2017.10.015DOI Listing
February 2018