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1.
J Environ Manage ; 322: 116059, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055096

RESUMO

Bisphenol A(BPA) is a common industrial chemical with significant adverse impacts on Environment and human health. The present work evaluates the efficacy of pulsed light (PL) and Fe2+ ions in activation of sodium percarbonate (SPC) to produce hydroxyl (OH•) and carbonate (CO3•-) radicals for efficient degradation of BPA. The effects of operational parameters such as solution pH, SPC and Fe2+ dose as well as the mixture composition were analyzed and the decomposition pathway of BPA proposed. The BPA was successfully degraded at the initial concentration of 15.0 mg/L and optimized conditions by the PL/Fe2+/SPC process (99.67 ± 0.29%). A rapid reduction in the degradation of BPA was observed with increasing pH due to OH• radicals quenching and also the precipitation of Fe2+. Under the optimized conditions, degradation of BPA by PL/Fe2+/SPC process was five-times faster than the individual process. The quenching experiments revealed that radical and non-radical pathways on BPA degradation was accomplished with OH•, CO3•-, O2•-, and 1O2, while OH• and CO3•- radicals (as a dominant radicals) have the contributions of 80.23% and 8.30%, respectively. Based on the detected byproducts, ring cleavage can be considered as the main transformation mechanism of BPA by the PL/Fe2+/SPC process.


Assuntos
Ferro , Poluentes Químicos da Água , Compostos Benzidrílicos/análise , Carbonatos/química , Humanos , Ferro/química , Oxirredução , Fenóis , Poluentes Químicos da Água/química
2.
Environ Res ; 211: 113059, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35257689

RESUMO

Sulfate-based advanced oxidation process mediated by zero-valent iron (ZVI) and ultraviolet radiation for the decomposition of sulfite salts resulted in the formation of strong oxidizing species (sulfate and hydroxide radicals) in aqueous solution is reported. Degradation of direct red 89 (DR89) dye via UV/ZVI/sulfite process was systematically investigated to evaluate the effect of pH, ZVI dose, sulfite, initial DR89 concentration, and reaction time on DR89 degradation. The synergy factor of UV/ZVI/sulfite process was found to be 2.23-times higher than the individual processes including ZVI, sulfite and UV. By increasing the ZVI dose from 100 mg/L to 300 mg/L, dye degradation was linearly enhanced from 67.12 ± 3.36% to 82.40 ± 4.12% by the UV/ZVI/sulfite process due to enhanced ZVI corrosion and sulfite activation. The highest degradation efficiency of 99.61 ± 0.02% was observed at pH of 5.0, [ZVI]0 = 300 mg/L, and [sulfite]0 = 400 mg/L. Toxicity assessment by Lepidium sativum demonstrated that treated dye solution by UV/ZVI/sulfite was within the non-toxic range. The application of optimal adaptive neuro-fuzzy inference system (ANFIS) to predict DR89 degradation indicated high accuracy of ANFIS model (R2 = 0.97 and RMSE = 0.051) via the UV/ZVI/sulfite process. It is suggested that UV/ZVI/sulfite process is suitable for industrial wastewater treatment.


Assuntos
Raios Ultravioleta , Poluentes Químicos da Água , Ferro/química , Oxirredução , Sulfatos , Sulfitos/toxicidade , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 28(27): 36029-36038, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33683593

RESUMO

Parabens are a group of antimicrobial preservatives applied in an extensive range of products and are suspected to impair fetal growth because of their disrupting effect on the endocrine system. We aimed to examine maternal urinary paraben concentrations and their neonates' outcome indexes. Methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) concentrations were measured in 105 maternal urine samples collected before delivery. Length, weight, and head circumference at birth were extracted from the mothers' delivery files. A multivariable linear regression analysis was performed to evaluate the association between paraben levels and neonatal anthropometric indices. The median levels of urinary parabens, especially BP, were higher than those in other countries. Prenatal urinary concentration of MP and BP showed a significantly positive association with birth weight in all neonates (ß = 0.79, 95% CI: 0.16, 1.41, and ß = 8.56, 95% CI: 3.95, 13.17, respectively), while these chemicals showed a significant negative association with head circumference (ß = - 0.002, 95% CI: - 0.004, - 0.000, and ß = - 0.016, 95% CI: - 0.030, - 0.002, respectively). A significant positive association between MP and birth length was also found (ß = 0.004, 95% CI: 0.00, 0.00) in all the neonates. In sex-stratified adjusted models, MP and BP were found to be associated, respectively, with higher birth length and weight in male neonates (ß = 0.008, 95% CI: - 0.001, 0.017, and ß = 7.948, 95% CI: 1.045, 14.851). In girls, maternal urinary MP, PP, and BP were associated with increased birth weight (ß = 0.831, 95% CI: 0.043, 1.620; ß = 4.178, 95% CI: 0.877, 7.480; and ß = 10.821, 95% CI: 3.545, 18.097, respectively), and MP and BP were associated with reduced head circumference at birth (ß = - 0.003, 95% CI: - 0.005, - 0.001, and ß = - 0.035, 95% CI: - 0.055, - 0.016). These results revealed potential impacts between neonatal growth and maternal exposure to parabens. However, these findings should be interpreted while considering the limitations of the present study.


Assuntos
Parabenos , Conservantes Farmacêuticos , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Masculino , Exposição Materna , Parabenos/análise , Parto , Gravidez
4.
Environ Pollut ; 277: 116632, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33640826

RESUMO

Application of alternating current in electrocoagulation and activation of persulfate (AEC-PS) for the effective removal of humic acid (HA) from aqueous solution was evaluated. In order to optimize the removal efficiency HA by the AEC-PS process, several influencing parameters such as pH, reaction time, PS dose, current density (CD), concentration of NaCl, initial concentration of HA, and coexisting cations and anions influence were investigated. From the batch experiments, the highest HA removal efficiency obtained was 99.4 ± 0.5% at pH of 5, reaction time of 25 min, CD of 4.5 mA/cm2, PS dose of 200 mg/L, and NaCl concentration of 0.75 g/L for an initial HA concentration of 30 mg/L. When CD increased from 1.25 to 4.5 mA/cm2, the HA removal efficiency was improved from 88.8 ± 4.4% to 96.1 ± 1.5%. In addition, the type of coexisting cations and anions exerted a significant role, leading to a reduction in the removal efficiency of HA. To investigate the dominant free activated radical, radical scavengers such as tert-butyl alcohol and ethanol were employed. It was observed that both OH and SO4- radicals substantially contributed to the removal of HA, and the contribution of SO4- radical was higher than that of OH radical, suggesting that AEC-PS process could serve as a novel and effective treatment technique for the removal of organic matters from aqueous sources.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Eletrocoagulação , Substâncias Húmicas , Oxirredução , Sulfatos , Poluentes Químicos da Água/análise
5.
J Environ Health Sci Eng ; 18(2): 617-628, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312588

RESUMO

PURPOSE: Parabens are used as preservatives in a wide range of products. Although parabens are generally known as safe, but recent evidences indicate that these compounds could lead to potential adverse effects on fetal growth. Thus, this study aimed to investigate the association between maternal parabens level in a sample of Iranian pregnant women with neonatal anthropometric measures. METHODS: This cross-sectional study was conducted in 2018-2019 in Isfahan city, Iran. Early morning urine samples were collected from 117 pregnant women who were in their first trimester of pregnancy. The urinary concentrations of four parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) were measured by gas chromatography-mass spectrometry. To compensate for variation in urine dilution, the paraben concentrations were adjusted by the creatinine levels. Associations between maternal parabens level and neonatal anthropometric indices were evaluated. RESULTS: The MeP, EtP, PrP, and BuP were detected in %92, %36, %65, and %89 of the urine samples, respectively. No significant association was observed between maternal parabens level and birth length (p-value>0.05). In adjusted model, the BuP concentration in first trimester urine samples showed significantly negative association with head circumference in female neonates [ß = -0.013, 95% CI: -0.024, -0.003], while positive significant association with that index in male neonates [ß = 0.019, 95% CI: 0.001, 0.038]. In subgroup analysis by sex, in crude and adjusted analyses BuP was found to be only associated with higher birth weight in female neonates. PrP also showed significant positive association with head circumference and birth weight of male neonates in crude analysis. CONCLUSION: Findings of this study on the association of urinary parabens of pregnant mothers with birth weight and head circumference suggest that maternal exposure to parabens might impact the fetal growth, However, these findings are based on cross-sectional data, thus the results should be interpreted with caution. The current findings underscore the necessity of providing more strict regulations in industries for limiting parabens use in their products, and the importance of public education for women of reproductive age for using paraben-free compounds.

6.
J Environ Health Sci Eng ; 18(2): 1239-1246, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312638

RESUMO

Asbestos, as with other pollutants in the air, has adverse effects on the health of human beings and animals. Today, the relationship between presence of asbestos fibers in the air breathed by humans and developing serious diseases such as lung cancer (asbestosis) and mesothelioma has been proven. The objectives of this study were to monitor the levels of asbestos fibers in ambient air of Mashhad, Iran during 2018, and to draw its Geographic Information System (GIS) distribution map for the city. In this descriptive study, 13 sampling points in Mashhad city were chosen. Sampling of asbestos was carried out for 3 hour during summer and winter at 2018. Sampling of asbestos was performed using MCE (Mixed Cellulose Ester) membrane filters (pour size 0.45 µm; diameter: 25 mm) and cassette holder and peripheral pump. The samples were the analyzed by the phase contrast microscopy (PCM) method (NIOSH7400). Also, to investigate the type of asbestos and for more accurate counting of fibers, Scanning Electron Microscopy (SEM) analysis was utilized. Meteorological parameter were recorded through portable devices. To draw the graphs, Excel, R and Arc GIS software were used. Results showed that the mean asbestos fiber concentrations were equal to 11.40 ± 2.14 and 14.38 ± 2.52 f/L in summer and winter, respectively. The maximum level of asbestos fiber was detected in the station of Baitolmoghaddas square by 26.64 ± 2.14 and 19.3 SEM f/L in winter and summer, respectively. High concentration of asbestos fiber observed in this study can be attributed to the heavy traffic, the presence of prominent industries in the vicinity of the study area, and topographic features. The results from this research recommends that suitable controlling policies should be regulated to reduce both ambient air asbestos and its adverse health endpoints in Mashhad.

7.
Environ Sci Pollut Res Int ; 27(13): 14723-14734, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32052325

RESUMO

Parabens are widely used as preservatives in cosmetics, medicines, and foods due to its antimicrobial properties. Concerns have been raised regarding the estrogenic activity and potential endocrine disruption effects of parabens. Studies on monitoring of paraben exposure in the Iranian population are very scarce. This study was carried out to measure urinary concentrations of parabens, to estimate their daily intake, and to identify some of the sociodemographic factors affecting exposure to these compounds. The concentrations of methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were measured in urine samples collected from 95 Iranian pregnant women by gas chromatography mass spectrometry. The highest median concentration was 87.0 µg/L for MP, followed by PP, EP, and BP with median concentrations of 15.6, 9.64, and 8.57 µg/L, respectively. Except BP, the urinary concentrations of other parabens were comparable to those in other countries. Also, the highest daily intake was related to MP (median = 16.5 µg/kg-BW/day), which is less than the acceptable daily intake (ADI). A significant positive correlation was observed between the measured parabens. Significant negative associations were observed between age and BP, BMI and EP as well as parity and PP. On the other hand, income and smoking were significantly positively associated with MP, BP and EP, BP, respectively. The urinary MP and BP concentrations were higher among the subjects with diploma education (P = 0.003 and P = 0.006, respectively), and during the spring, urinary MP concentration was higher than other seasons. The results showed that Iranian pregnant women are more prone to parabens and their urinary paraben concentrations are associated with sociodemographic factors. This result could serve as a basis for evaluating the rate of exposure of the Iranian population to parabens in future studies.


Assuntos
Cosméticos , Parabenos/análise , Feminino , Humanos , Irã (Geográfico) , Gravidez , Conservantes Farmacêuticos , Estações do Ano
8.
MethodsX ; 6: 1716-1727, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384570

RESUMO

Nitrate is one of the most important contaminants that can release into the environment predominantly as a result of anthropogenic processes. Excessive intake of nitrates may increase the risk of certain types of cancer. The aim of this study was to investigate the concentration of nitrate in drinking water and its health to people in Iran. This cross-sectional study has performed in 2019. Nitrate concentrations in drinking water supplies were obtained from peer-reviewed publications. Monte Carlo stimulations and mathematical models were used to determine the excess cancer risk. Risk level for assessing the carcinogen risk was 10-5 (1 per 100,000 persons). Nitrate concentrations and cancer risk related to nitrate were classified by GIS software. According to the obtained results, the drinking water supplies of Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) have higher nitrate concentrations than the limit recommended by WHO and Institute of Standards and industrial Research of Iran (ISIRI). The estimated cancer risks for the provinces of Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) were in the no negligible range set by the Health Canada and WHO. The majority of Iran provinces that have impermissible level of nitrate in drinking water supplies had a significant association between cancer prevalence and nitrate exposure. •The findings demonstrated that carcinogen risk values of nitrate exposure through drinking water was 0.001%.•Results showed that Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) are more exposed to additional cancer risk related to nitrosamine.•The results of this study is considered as the comprehensive report that indicate the association between gastrointestinal cancer and nitrate exposure through drinking water.

9.
MethodsX ; 6: 377-382, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30859073

RESUMO

Hazardous wastes (HWs) is waste that has substantial or potential threats to public health or the environment. The aim this study is evaluation of quantitative and qualitative of hazardous waste in laboratories of Isfahan University of Medical Sciences (IUMS), Isfahan, Iran. In this data research, four out of ten faculties of IUMS that produce the highest amount of HWs were selected for collection of required data. The required information collected by using interview with laboratory staffs, completion of questionnaire, and refer to the available documents. The 33 laboratories (including 18 and 15 chemical and biological laboratories, respectively) and one clinic were selected. The obtained data showed that annually 2609.9 kg HWs generated in IUMS. The dentistry, public health, medical, and pharmacy faculties were produced 104, 266.6, 793.9, and 1445.4 kg of HW per year, respectively that they were including 4%, 10%, 31%, and 55% in the total amount of generated HW. According to the acquired result, to protect the health of the environment, IUMS must establish a comprehensive solid waste management programs for prevention and reduction, higher rates of recycling, and managing HWs in all faculties.

10.
Data Brief ; 22: 676-686, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30671516

RESUMO

In this data article, natural (NL) and manganese oxide-modified LECA (MML) adsorbents were applied for adsorptive removal of Tetracycline (TC) from aqueous solution. The used adsorbents was characterized using fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence spectroscopy (XRF). The chemical analysis of XRF data revealed increased chemical composition of Mn as MnO to 8.96 wt%. The SEM patterns were illustrated the extent of surface and enhanced porosity in MML with Mn. In optimum operational conditions, maximum removal percentage of TC was achieved at 51.5 and 99.4% using NL and MML, respectively. The maximum adsorption capacities obtained from Langmuir modeling were 6.89 and 9.24 for NL and MML, respectively. The modeling of the adsorption kinetics revealed that TC adsorption by both NL and MML adsorbents was best-fitted with a pseudo-first-order model (R 2 = 0.978). The isotherm studies of TC adsorption by MML showed that the Freundlich isotherm was the most appropriate model, with a higher coefficient of determination. The obtained data was illustrated that high competitive capacity of chloride and hardness ions compared with other ions against TC adsorption.

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