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1.
Sci Rep ; 14(1): 8562, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609448

RESUMO

This study investigated the association between serum concentrations of Polychlorinated Biphenyls (PCBs) and the risk of type 2 diabetes within the general population. A ten-year follow-up historical cohort study was conducted during 2009-2019 as part of the Bushehr MONICA cohort study in Iran. Of 893 non-diabetes participants at base line, 181 individuals were included in the study. The concentration of nine PCB congeners was measured in individuals' serum samples at baseline, and the risk of type 2 diabetes was determined based on fasting blood sugar at the end of follow-up. Multiple logistic regression models were used to assess the study outcomes after adjusting for covariates. This study included 59 diabetes individuals (32.6%; mean [SD] age: 58.64 [8.05]) and 122 non-diabetes individuals (67.4%; mean [SD] age: 52.75 [8.68]). Multivariable analysis revealed that a one-tertile increase (increasing from 33rd centile to 67th centile) in Σ non-dioxin-like-PCBs (OR 2.749, 95% CI 1.066-7.089), Σ dioxin-like-PCBs (OR 4.842, 95% CI 1.911-12.269), and Σ PCBs (OR 2.887, 95% CI 1.120-7.441) significantly associated with an increased risk of type 2 diabetes. The strongest association was obtained for dioxin-like PCBs. The results highlight a significant correlation between PCB exposure and an increased risk of type 2 diabetes. The evidence suggests that additional epidemiological studies are necessary to clarify the link between PCBs and diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Humanos , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/epidemiologia , Estudos de Coortes , Seguimentos
2.
Waste Manag ; 180: 76-84, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547758

RESUMO

Humans are at risk of exposure to phthalates due to the widespread use of plasticized plastics, and one of the major concerns is occupational exposure. The present study investigated occupational exposure to phthalates at one of the greatest solid waste management sites in the second-largest country in the Middle East. Carcinogenic and non-carcinogenic health risks were assessed by human biomonitoring (HBM). The concentration of phthalate esters was determined using gas chromatography-mass spectrometry (GC-MS), and the daily intake (DI) of phthalate was calculated based on the adjusted urinary creatinine concentrations. Moreover, carcinogenic and non-carcinogenic risks were assessed. Monte Carlo simulations were performed for uncertainty and sensitivity analysis. The highest concentration recorded was 130.80 µg/g creatinine for mono-ethyl phthalate (MEP) among the composting group, while the lowest concentration was 0.49 µg/g creatinine for Monobenzyl phthalate (MBzP) among the office group. All estimates of daily intake were below the reference concentration, and differences between the DI at site sections were statistically significant (p < 0.05). The non-carcinogenic risk level was negligible. The excess lifetime cancer risk (ELCR) values corresponding to di-(2-ethylhexyl) phthalate (DEHP) exposure were 2.07E-04 among the composting group and 2.07E-04 among the processing group, posing a definite risk. The carcinogenic risk value among the office group was in a possible risk category with ELCR values of 9.75 E-05. The on-site workers of waste management sites can be highly exposed to phthalates, and their health risk is considerable. Appropriate measures and interventions should be considered to reduce occupational exposure to phthalates.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Humanos , Exposição Ambiental/análise , Poluentes Ambientais/urina , Monitoramento Biológico , Creatinina/urina , Ácidos Ftálicos/urina , Medição de Risco
3.
Environ Geochem Health ; 46(2): 68, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38342781

RESUMO

These days, the presence of pesticide residues in drinking water sources is a serious concern. In drinking water treatment plants (DWTPs), various methods have been proposed to remove pesticide residues. This study was designed with the objectives of monitoring the occurrence and seasonal variations of pesticides in the output of drinking water treatment plants in two Northern provinces of Iran, Gilan and Golestan, and identifying their human health risks. Seventeen pesticide residues from different chemical structures were determined by using a gas chromatograph-mass spectrometer (GC-MS). The results showed that only Alachlor, Diazinon, Fenitrothion, Malathion, and Chlorpyrifos were detected. The pesticide concentrations ranged from ND to 405.3 ng/L and were higher in the first half-year period. The total non-carcinogenic human health risks was in safe range for infants, children, and adults (HI < 1). The carcinogenic human health risks of Alachlor for infants, children, and adults were in the range of 4.3 × 10-7 to 1.3 × 10-6, 2.0 × 10-7 to 9.6 × 10-7, and 1.1 × 10-7 to 5.5 × 10-7, respectively. These values do not pose health risks for adults and children, but may present a possible cancer risk for infants in two DWTPs of Golestan. In conclusion, considering the possibility of exposure to these pesticides through other routes, simultaneously, it is suggested to carry out a study that examines the level of risk by considering all exposure routes. We also propose stricter regulations for the sale and use of pesticides in Iran.


Assuntos
Acetamidas , Água Potável , Resíduos de Praguicidas , Praguicidas , Adulto , Criança , Humanos , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Irã (Geográfico) , Praguicidas/toxicidade , Praguicidas/análise , Medição de Risco
4.
EMBO Mol Med ; 15(11): e17833, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37702369

RESUMO

Snyder-Robinson syndrome (SRS) results from mutations in spermine synthase (SMS), which converts the polyamine spermidine into spermine. Affecting primarily males, common manifestations of SRS include intellectual disability, osteoporosis, hypotonia, and seizures. Symptom management is the only treatment. Reduced SMS activity causes spermidine accumulation while spermine levels are reduced. The resulting exaggerated spermidine:spermine ratio is a biochemical hallmark of SRS that tends to correlate with symptom severity. Our studies aim to pharmacologically manipulate polyamine metabolism to correct this imbalance as a therapeutic strategy for SRS. Here we report the repurposing of 2-difluoromethylornithine (DFMO), an FDA-approved inhibitor of polyamine biosynthesis, in rebalancing spermidine:spermine ratios in SRS patient cells. Mechanistic in vitro studies demonstrate that, while reducing spermidine biosynthesis, DFMO also stimulates the conversion of spermidine into spermine in hypomorphic SMS cells and induces uptake of exogenous spermine, altogether reducing the aberrant ratios. In a Drosophila SRS model characterized by reduced lifespan, DFMO improves longevity. As nearly all SRS patient mutations are hypomorphic, these studies form a strong foundation for translational studies with significant therapeutic potential.


Assuntos
Poliaminas , Espermidina , Masculino , Humanos , Poliaminas/metabolismo , Espermidina/metabolismo , Espermidina/farmacologia , Espermina/metabolismo , Eflornitina/farmacologia , Eflornitina/uso terapêutico , Espermina Sintase/genética , Espermina Sintase/metabolismo
5.
bioRxiv ; 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37034775

RESUMO

Snyder-Robinson Syndrome (SRS) is caused by mutations in the spermine synthase (SMS) gene, the enzyme product of which converts the polyamine spermidine into spermine. Affecting primarily males, common manifestations of SRS include intellectual disability, osteoporosis, hypotonic musculature, and seizures, along with other more variable symptoms. Currently, medical management focuses on treating these symptoms without addressing the underlying molecular cause of the disease. Reduced SMS catalytic activity in cells of SRS patients causes the accumulation of spermidine, while spermine levels are reduced. The resulting exaggeration in spermidine-to-spermine ratio is a biochemical hallmark of SRS that tends to correlate with symptom severity in the patient. Our studies aim to pharmacologically manipulate polyamine metabolism to correct this polyamine imbalance and investigate the potential of this approach as a therapeutic strategy for affected individuals. Here we report the use of difluoromethylornithine (DFMO; eflornithine), an FDA-approved inhibitor of polyamine biosynthesis, in re-establishing normal spermidine-to-spermine ratios in SRS patient cells. Through mechanistic studies, we demonstrate that, while reducing spermidine biosynthesis, DFMO also stimulates the conversion of existing spermidine into spermine in cell lines with hypomorphic variants of SMS. Further, DFMO treatment induces a compensatory uptake of exogenous polyamines, including spermine and spermine mimetics, cooperatively reducing spermidine and increasing spermine levels. In a Drosophila SRS model characterized by reduced lifespan, adding DFMO to the feed extended lifespan. As nearly all known SRS patient mutations are hypomorphic, these studies form a foundation for future translational studies with significant therapeutic potential.

6.
Environ Sci Pollut Res Int ; 29(37): 55437-55456, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35676570

RESUMO

This systematic review aims to identify the sources of exposure to polychlorinated biphenyls (PCBs), portioning, and human health risk assessment in Iran. The literature was searched in the international databases of Web of Science, PubMed, Scopus, Google Scholar, and the national databases of SID and MagIran up to November 14, 2020. Among all 153 articles, 21 eligible papers were identified. Among them, only one article was related to drinking water, the rest was related to food and soil, and no article was found on ambient air. The corrected portion of each exposure source was determined to be 90% for food, 9% for water, and 1% for air. The total hazard quotient (HQ) was determined to be within an unsafe range, and the total excess lifetime cancer risk (ELCR) was determined to be at a high risk of oral carcinogenesis. It is suggested that a comprehensive study be conducted in a specific period for all sources of exposure in all counties of Iran. Moreover, it is recommended that the policymakers set national standards for this pollutant in near future in some sources of exposure (e.g., drinking water) which have no standards in Iran.


Assuntos
Água Potável , Bifenilos Policlorados , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Bifenilos Policlorados/análise , Medição de Risco , Solo
7.
J Environ Health Sci Eng ; 19(2): 1607-1611, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34900292

RESUMO

BACKGROUND: 1, 3-Butadiene is a famous industrial compound which occurs in gasoline and diesel exhaust and in cigarette smoke. Based on little evidence of carcinogenicity in laboratory animals and humans, it was classified as a probable carcinogen. The potential of exposure to gasoline and diesel exhaust containing these chemical compounds is very considerable in urban areas. According to studies, in estimation of workers' chronic exposure with biological samples, analysis of the concentration of related hemoglobin adducts seems to give the most valid estimation of exposure. METHODS: This study designed to determine the level of chronic exposure in gas station workers and traffic policemen during routine work shift, by an appropriate biological marker. In this regards, 25 gas station workers, 25 policemen engaged in traffic control, and 25 occupationally non-exposed persons were studied. Blood samples were obtained after the work shift from each person. The level of selected hemoglobin adduct, 1- and 2-hydroxy-3-butenyl valine (MHBVal) was determined by using GC-MS after a modified Edman degradation and a further acetylation. RESULTS: There were significant differences among the mean concentrations of MHBVal in blood samples of gas station workers, policemen and occupationally non-exposed persons. The mean airborne levels of 1, 3-Butadiene over 60 days, differed significantly among different studied groups (ANOVA: p < 0.05 and Kruskal-Wallis test: p < 0.05). CONCLUSION: There was a significant difference in MHBVal concentrations between job categories (p < 0.05 by ANOVA and Kruskal-Wallis test), and gas station workers and policemen were found to be probably the most exposed groups in this research.

8.
J Environ Health Sci Eng ; 19(2): 1735-1742, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34900302

RESUMO

PURPOSE: Metal contamination in water is a worldwide persistent problem. We developed a nano-adsorbent, TEPA-MIL-101(Cr) that exhibits effective removal of heavy metals from real water samples. METHODS: MIL-101(Cr) was synthesized under solvo-thermal condition. Then MIL-101(Cr) was dehydrated and degassed at high temperature under vacuum to generate the coordinately unsaturated sites which are used for tetraethylene pentamine (TEPA) grafting. The structures, morphologies, and compositions of the sorbents have been characterized. Langmuir and Freundlich isotherm models were applied for describing the adsorption process onto TEPA-MIL-101(Cr). RESULTS: The successful grafting of TEPA on MIL-101(Cr) was verified by Fourier transform infrared. The results of X-ray diffraction, scanning electron microscopy, and CHN analysis show that the structure of TEPA-MIL-101(Cr) retains the original structure of MIL-101(Cr). Thermogravimetric analysis indicates thermo-stability of the adsorbent up to 300 °C. Optimal conditions for adsorption were determined as pH = 6.5 and contact time = 1 h. The adsorption capacities of TEPA-MIL-101(Cr) for Pb(II), Cu(II), Cd(II), and Co(II) from aqueous samples were 227.5, 217.7, 221.4, and 215.6 mg/g respectively, which is on average more than 8 times that of MIL-101(Cr). Analysis of Langmuir and Freundlich models for describing the adsorption isotherms of TEPA-MIL-101(Cr) reveals that the metal ions were absorbed onto TEPA-MIL-101(Cr) by a favorable physical absorption process. CONCLUSIONS: TEPA-MIL-101(Cr) was synthesized successfully by a simple, and cost-effective method. The removal efficiency of TEPA-MIL-101(Cr) for the metal ions achieved more than 95 % in real water samples, which in addition to its thermal stability character make it a promising candidate for water treatment purposes.

9.
J Environ Health Sci Eng ; 19(1): 357-363, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150240

RESUMO

High-level toxic metal exposure has become rare in the recent years. Although, it has not known whether relatively lower exposure may adversely affect human reproductive system. Spontaneous abortion (SA) is a serious reproductive problem, which, in many cases, the cause(s) is not clearly understood. To assess the relationship between prenatal blood level of metals and SA risk, we compared blood concentration of some heavy metals in samples taken from mothers recruited in Tehran Environment and Neurodevelopmental Defects (TEND) study conducted on apparently healthy pregnant women in Tehran, Iran who subsequently experienced spontaneous abortion with mothers who their pregnancy ended to live births. During early gestation, 206 women were enrolled to the survey and followed up till fetal abortion or baby deliveries occur. Blood metal concentrations were measured using an inductively coupled plasma mass spectrometer. The mean blood levels of lead, antimony, and nickel were higher in SA than ongoing pregnancy; however, this difference was not statistically significant. When adjusted for covariates, the logistic regression analysis showed significant association between maternal age and the risk of SA in all models. Among toxic metals only antimony had a noticeable positive relation with the risk of SA (OR: 1.65, 95% CI:1.08-2.52, P value: 0.02). Pearson's correlation coefficient showed significant (P < 0.05) positive correlations among prenatal blood metals levels, except for nickel. Although the present study failed to provide strong evidence for the effects of toxic metals on the occurrence of SA at the relatively low-levels, these metals should be avoided in women who plan pregnancy and/or during the early stages of gestation to prevent the chance of adverse effects.

10.
J Environ Health Sci Eng ; 19(1): 1043-1046, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150292

RESUMO

BACKGROUND: Despite frequent warnings of irreversible side effects of smoking in public media, the consumption of cigarette is increasing dramatically in both developed and developing countries. Cigarette smoke contains different kinds of chemicals, which all capable of inducing free radical production. There are studies supporting the idea that these free radicals have adverse effects in body and causing oxidative stress. Total antioxidant capacity (TAC) is considered as the total effect of all antioxidants and total oxidant status (TOS) shows the total effect of all oxidants existing in body fluids. Therefore, this research focused on the measurement and comparison of these markers in the serum of university students. METHODS: This study designed to determine the total antioxidant capacity, total oxidant status and oxidative stress index levels in the serum of active smokers, passive smokers and non-smokers in university students. A total of 150 participants were included in the study. The study population consisted of 50 smokers, 50 passive smokers and 50 nonsmokers. In serum samples, the levels of TAC and TOS were measured by spectrophotometric method using Rel Assay Diagnostics kit. Oxidative stress index was calculated through the TOS/TAC formula in three groups. RESULTS: The mean value TAC levels in serum samples of the three groups of smokers, passive smokers and nonsmokers were 1.096, 1.220 and 1.844 mmol Trolox equivalent/L, respectively, which were significantly greater in nonsmokers than smokers and passive smokers. The mean value TOS levels in serum samples of the three groups of smokers, passive smokers and nonsmokers were 13.747, 11.099 and 7.6510 µmol H2O2 equivalent/L, respectively, which were significantly lower in nonsmokers than two other groups. OSI values in smokers and passive smokers were significantly higher than the control group. CONCLUSIONS: According to our findings, the antioxidant capacity in all smokers (active and inactive) was less than the control group (non-smokers). The results of this study showed that smoking reduces the activity of the antioxidant defense system and activates the oxidative stress system in the body. Based on these findings, it can be clearly concluded that the decrease in antioxidant capacity in smokers is associated with increased production of oxidants and free radicals.

11.
Sci Rep ; 11(1): 12922, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155256

RESUMO

Inflammatory biomarkers in exhaled breath condensate (EBC) are measured to estimate the effects of air pollution on humans. The present study was conducted to investigate the relationship between particulate matter and inflammatory biomarkers in blood plasma and exhaled air in young adults. The obtained results were compared in two periods; i.e., winter and summer. GRIMM Dust Monitors were used to measure PM10, PM2.5, and PM1 in indoor and outdoor air. A total of 40 healthy young adults exhaling air condensate were collected. Then, biomarkers of interleukin-6 (IL-6), Nitrosothiols (RS-NOs), and Tumor necrosis factor-soluble receptor-II (sTNFRII) were measured by 96 wells method ELISA and commercial kits (HS600B R&D Kit and ALX-850-037-KI01) in EBC while interleukin-6 (IL-6), sTNFRII and White Blood Cell (WBC) were measured in blood plasma in two periods of February 2013 (winter) and May 2013 (summer). Significant association was found between particulate matter and the white blood cell count (p < 0.001), as well as plasma sTNFRII levels (p-value = 0.001). No significant relationship was found between particulate matter with RS-NOs (p = 0.128), EBC RSNOs (p-value = 0.128), and plasma IL-6 (p-value = 0.167). In addition, there was no significant relationship between interleukin-6 of exhaled air with interleukin-6 of plasma (p-value < 0.792 in the first period and < 0.890 in the second period). sTNFRII was not detected in EBC. Considering the direct effect between increasing some biomarkers in blood and EBC and particulate matter, it is concluded that air pollution causes this increasing.


Assuntos
Biomarcadores , Expiração , Mediadores da Inflamação/metabolismo , Material Particulado/análise , Adolescente , Adulto , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Testes Respiratórios , Meio Ambiente , Feminino , Voluntários Saudáveis , Humanos , Mediadores da Inflamação/sangue , Irã (Geográfico) , Masculino , Adulto Jovem
12.
Environ Sci Pollut Res Int ; 28(21): 26223-26251, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33791963

RESUMO

Water quality is one of the most important indices for public health especially for drinking water consumptions. This study was conducted to survey the presence of heavy metals in drinking water resources of Iran using a systematic review and meta-analysis. The literature search was conducted in data bases of PubMed, Web of Science, EMBASE, Scopus, Google Scholar, and some Persian databases up to 31 July 2018. Of all the articles reviewed (1151 articles), 61 papers were eligible for systematic review. Results indicated variable heterogeneity between studies for different pollutants (I2 between 0 and 100). A subgroup analysis was performed for three different types of water resources such as drinking water, groundwater, and surface water to find the possible source of the heterogeneity. The pooled mean concentration level of iron was the highest at 255.8 (95% CI = 79.48-432.13 µg/l) and vanadium the lowest at 3.21 (95% CI = 1.45-4.98 µg/l). The sequence of metal concentration (µg/l) in descending order is as follows: Fe (255.8) > B (159.81) > Al (158.5) > Zn (130.73) > As (85.85) > Mn (51.61) > Cu (47.98) > Se (42.68) > Pb (37.22) > Co (22.76) > Mo (18.92) > Ni (16.79) > Cr (13.47) > Hg (4.49) > Cd (4.19) > V (3.21). The mean pooled concentration level of Al, As, Se, Pb, and Cd was higher than the WHO guideline and Iran Standard, and the rest of the metals had lower mean pooled concentration level. Pb and Cd were the common heavy metals that existed in all subgroups. As a recommendation, the relationship assessment of water parameters and heavy metals could be addressed in future studies of Iran's water resources.


Assuntos
Água Potável , Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Irã (Geográfico) , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise , Recursos Hídricos
13.
J Environ Health Sci Eng ; 18(2): 733-742, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312598

RESUMO

PURPOSE: To advance knowledge about childhood neurodevelopmental disorders and study their environmental determinants, we conducted a study in Tehran, Iran to assess the feasibility of prospective birth cohort study. METHODS: We evaluated participation of pregnant women, feasibility of sampling biological material, and health care services availability in Tehran in four steps: (1) first trimester of pregnancy; (2) third trimester of pregnancy; (3) at delivery; and (4) two to three months after delivery. We collected related data through questionnaires, also various biological samples were obtained from mothers (blood, urine, milk and nails-hands and feet) and newborns (umbilical cord blood, meconium, and urine samples) from February 2016 to October 2017. RESULTS: overall 838 eligible pregnant women were approached. The participation rate was 206(25%) in our study and about 185(90%) of subjects were recruited in hospitals. Out of 206 participants in the first trimester, blood, urine, hand nail, and foot nail samples were collected from 206(100%),193(93%), 205(99%), and 205(99%), respectively. These values dropped to 65(54%), 83(69%), 84(70%), and 84(70%) for the remaining participants 120(58%) in the third trimester, respectively. Also, we gathered milk samples from 125(60%) of mothers at two to three months after delivery. CONCLUSION: Our findings suggest that hospitals were better places for recruitment of subjects in a birth cohort in Tehran. We further concluded that birth cohort study recruitment can be improved by choosing appropriate gestational ages. Obtaining the newborn's urine, meconium, and umbilical cord blood were challenging procedures and require good collaboration between hospital staff and researchers.

14.
J Environ Health Sci Eng ; 18(2): 1265-1269, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312640

RESUMO

BACKGROUND: 1, 3-Butadiene is an important industrial compound. Based on sufficient evidence of carcinogenicity in laboratory animals and humans, the International Agency for Research on Cancer, in 1999, classified 1, 3-Butadiene as a probable carcinogen to humans (group 2A). The potential for exposure to vehicle exhaust containing these chemical compounds is very noticeable in urban locations. Exposure to incomplete combustion of gasoline has been a long time concern in many occupational fields, including policemen, service stations, and the petroleum industry but in Iran has rarely been studied. METHODS: This study designed to determine the exposure levels for traffic policemen and gas station workers during routine work shift, by biological monitoring. With this aim, 25 policemen engaged in traffic control, 25 gas station workers and 25 occupationally non-exposed persons were investigated. Spot urine samples were obtained prior to and at the end of the work shift from each subject. The urinary levels of selected urinary metabolites (MHBMA and DHBMA) were determined by using LC-MS/MS. RESULTS: There were significant differences among the mean urinary concentrations of DHBMA in pre-shift samples of policemen, gas station workers and occupationally non-exposed persons. The mean urinary concentrations of DHBMA differed significantly among post-shift samples of policemen and gas station (ANOVA: p < 0.05 and Kruskal-Wallis test: p < 0.05). CONCLUSIONS: There was a significant difference in DHBMA concentrations between job categories (p < 0.05 by ANOVA and Kruskal-Wallis test), and policemen and gas station workers were found to be probably the most exposed groups in this study.

15.
Environ Res ; 191: 110068, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32846179

RESUMO

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-3). In specific, they were exposed to benzene concentrations of 11 µg m-3. Moreover, the total BTEX (t-BTEX) concentrations measured over the conveyor belt was 198 µg m-3 at most, followed by trommel (104), and active landfills (43). The mean concentration of ambient t-BTEX in Tehran is 100 µg m-3. 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-3, 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.


Assuntos
Poluentes Atmosféricos , Xilenos , Poluentes Atmosféricos/análise , Benzeno/análise , Benzeno/toxicidade , Derivados de Benzeno/análise , Derivados de Benzeno/toxicidade , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Medição de Risco , Resíduos Sólidos , Tolueno/análise , Tolueno/toxicidade , Xilenos/análise , Xilenos/toxicidade
16.
Environ Res ; 184: 109331, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32169736

RESUMO

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.


Assuntos
Poluentes Ambientais , Exposição Materna , Transtornos do Neurodesenvolvimento , Fenóis , Peso ao Nascer , Estudos de Coortes , Poluentes Ambientais/toxicidade , Feminino , Humanos , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , Exposição Materna/efeitos adversos , Mães , Fenóis/toxicidade , Gravidez , Resultado da Gravidez , Estudos Prospectivos
17.
Mar Pollut Bull ; 145: 536-546, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590821

RESUMO

Microplastic particles (<5 mm), which are an emerging threat, are commonly found in marine ecosystems worldwide. This study investigated the effect of different types of coastal land use on microplastic frequency and distribution on the coastline of Bandar Abbas city; this study used a large sample compared to that used in other studies conducted in this region. The average number of microplastics was determined as 3252 ±â€¯2766 microplastics/m2 (±SD). ATR FT-IR spectroscopy showed that the dominant microplastic particles are expanded polystyrene, polyethylene terephthalate, polypropylene, and polyethylene. Statistical analysis showed a significant difference in microplastic contamination levels between the urban and nonuse beaches. This shows that heavily urbanized areas and human activities have significant effects on the dispersion and frequency of microplastics in the coastal areas of Bandar Abbas. Periodical coast-based cleanup and studies on microplastic pollution and their fluxes by comprehensive sampling are mostly recommended for the Persian Gulf coastline.


Assuntos
Microplásticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Oceano Índico , Irã (Geográfico) , Microplásticos/química , Polietileno/análise , Polietileno/química , Polipropilenos/análise , Polipropilenos/química , Poliestirenos/análise , Poliestirenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Urbanização , Poluentes Químicos da Água/química
18.
Environ Monit Assess ; 191(5): 286, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30997562

RESUMO

Benzene, toluene, ethylbenzene, and xylene (BTEX) concentrations were measured in beauty salons (BS) and in the urine of the beauty practitioners and a control group. Indoor and outdoor concentrations of BTEX were measured in 36 randomly selected salons. Before- and after-shift urinary BTEX were measured from one female non-smoker employee in each salon, and repeated three times. Clinical symptoms in that beautician were assessed by a physician. Thirty-six unexposed women were included as the control group. Cancer and non-cancer risks of exposure were assessed using deterministic and stochastic methods. Average indoor concentrations of BTEX were higher than those in the ambient air. Urinary BTEX concentrations in the beauty practitioners were significantly higher than in the control group. Linear regression showed that 77% of urinary benzene and toluene variations can be explained by their airborne concentrations. A positive significant relationship was found between age and urinary BTEX concentrations. Although the BTEX cancer and non-cancer risks were not significant, BTEX led to irritation of the eyes, throat, lung, and nose. In addition, toluene caused menstrual disorders among beauty practitioners. These results suggest that it is essential to decrease the exposure of beauty practitioners to BTEX compounds.


Assuntos
Derivados de Benzeno/análise , Benzeno/análise , Tolueno/análise , Xilenos/análise , Poluentes Atmosféricos/análise , Beleza , Monitoramento Ambiental/métodos , Feminino , Humanos , Modelos Lineares , Medição de Risco/métodos
19.
Environ Res ; 173: 419-431, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30974368

RESUMO

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.


Assuntos
Exposição Materna/estatística & dados numéricos , Parabenos , Efeitos Tardios da Exposição Pré-Natal , Feminino , Humanos , Parto , Gravidez , Conservantes Farmacêuticos
20.
J Trace Elem Med Biol ; 52: 6-11, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30732901

RESUMO

Iodine deficiency disorders include a wide range of metabolic and nonmetabolic disorders including goiter. To control IDDs, the World Health Organization and responsible agencies in countries established daily iodine uptake. Almost all the countries in the world provide the required iodine through salt iodisation. IDDs are not completely eradicable, so monitoring the salt iodisation programme is necessary for control of IDDs. In Iran, a salt iodisation programme was started in 1996. In this study, we took salt samples from all legally produced salt brands in Iran in 30 provinces and measured iodine concentration. The results of the monitoring programme for iodine concentration in schoolchildren's urine was used to compare accessibility to iodized salts and health outcomes. The results show that more than 80% of available salts have a suitable or acceptable concentration of iodine. Despite large variance in iodine concentration in available salt in some provinces, the median of iodine concentration in salts is within an acceptable range. Also, the urinary concentration of iodine (national median = 161) confirms that shortage of iodine intake is very low in Iran. The high rate of salt consumption of the Iranian people also has a significant effect on iodine uptake, but can lead to hyperthyroidism and hypertension that must be controlled.


Assuntos
Nível de Saúde , Iodo/análise , Iodo/provisão & distribuição , Estado Nutricional , Cloreto de Sódio na Dieta/administração & dosagem , Cloreto de Sódio na Dieta/análise , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Iodo/administração & dosagem , Irã (Geográfico)/epidemiologia , Masculino
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