RESUMO
BACKGROUND: 4-hydroxychlorothalonil (HCT, R182281), a transformation product of the fungicide chlorothalonil, was recently identified in human serum and breast milk. There are indications that HCT may be more toxic and environmentally persistent than chlorothalonil. OBJECTIVE: Our aim was to investigate serum concentrations of HCT in pregnant women in Sweden and Costa Rica. METHODS: We developed a quantitative analytical method for HCT using liquid chromatography tandem mass spectrometry. We measured HCT in 1808 serum samples from pregnant women from the general population in Sweden (1997-2015) and in 632 samples from 393 pregnant women from an agricultural population in Costa Rica (2010-2011). In Swedish samples, we assessed time trends and investigated seasonality. In the Costa Rican samples, we evaluated variability between and within women and explanatory variables of HCT concentrations. RESULTS: HCT was detected in all serum samples, and the limit of detection was 0.1 µg/L. The median HCT concentration in the Swedish samples was 4.1 µg/L (interquartile range [IQR] of 2.9 - 5.8 µg/L), and 3.9 times higher in the Costa Rican samples (median: 16.1 µg/L; IQR: 10.6 - 25.0 µg/L). We found clear seasonal variation with higher concentrations in the first half of each year among Swedish women. In the Costa Rican study, women working in agriculture and living near banana plantations had higher HCT concentrations, whilst higher parity and having a partner working in agriculture were associated with decreased HCT, and no clear seasonal pattern was observed. IMPACT STATEMENT: For the first time, this study quantifies human exposure to the fungicide chlorothalonil and/or its transformation product 4-hydroxychlorothalonil (HCT, R182281) and finds higher serum concentrations in women from a tropical agricultural setting as compared with women from the general population in Sweden.
RESUMO
BACKGROUND: Women living in the Bolivian Andes are environmentally exposed to arsenic, yet there is scarce information about arsenic-related effects in this region. Several biomarkers for telomere length and oxidative stress (mitochondrial DNA copy number, mtDNAcn; 8-Oxo-2'-deoxyguanosine, 8-oxo-dG; and 4-hydroxy nonenal mercapturic acid, 4-HNE-MA) have been previously linked to arsenic, and some of which are prospective biomarkers for cancer risk. OBJECTIVE AND HYPOTHESIS: To evaluate associations between arsenic exposure and telomere length, mtDNAcn, 8-oxo-dG, and 4-HNE-MA in Bolivians. Arsenic exposure was hypothesized to be positively associated with all four toxicity biomarkers, particularly in individuals with a less efficient arsenic metabolism. METHODS: The study encompassed 193 indigenous women. Arsenic exposure was assessed in urine as the sum of inorganic arsenic metabolite concentrations (U-As) measured by HPLC-HG-ICP-MS, and in whole blood as total arsenic (B-As) measured by ICP-MS. Efficiency of arsenic metabolism was evaluated by a polymorphism (rs3740393) in the main arsenic methylating gene AS3MT measured by TaqMan allelic discrimination, and by the relative fractions of urinary inorganic arsenic metabolites. Telomere length and mtDNAcn were determined in peripheral blood leukocytes by quantitative PCR, and urinary 8-oxo-dG and 4-HNE-MA by LC-MS/MS. RESULTS: U-As and B-As were associated with longer telomeres and higher mtDNAcn, particularly in women with a less efficient arsenic metabolism. Urinary 8-oxo-dG and 4-HNE-MA were positively associated with U-As, but only 4-HNE-MA was associated with B-As. Arsenic metabolism efficiency did not have a clear effect on the concentrations of either of these biomarkers. CONCLUSION: Bolivian women showed indications of arsenic toxicity, measured by four different biomarkers. Telomere length, mtDNAcn, and 4-HNE-MA were positively associated with both U-As and B-As. The association of arsenic exposure with telomere length and mtDNAcn was only present in Bolivian women with a less efficient metabolism. These findings call for additional efforts to evaluate and reduce arsenic exposure in Bolivia.
Assuntos
Arsênio , Biomarcadores , Bolívia , Cromatografia Líquida , Feminino , Humanos , Povos Indígenas , Metiltransferases , Estresse Oxidativo/genética , Espectrometria de Massas em Tandem , Telômero/genéticaRESUMO
Endocrine disrupting chemicals (EDCs) from the environment are associated with reproductive abnormalities (i.e. decreased sperm concentration; increased endometriosis) and alterations of the cardiovascular system (i.e. increased blood pressure and risk of coronary disease). Some phthalates esters have been identified as EDCs, for which inhalation is considered as one of the routes of exposure. However, only little is known regarding inhalational exposure to EDCs via urban airborne particles. In the present study, we report the monthly concentration of 8 phthalate esters measured in PM10 and PM2.5 collected and recovered during 7 months in a highly populated area of Mexico City. Using the levels of PM10 and PM2.5 reported by the automatized network of environmental monitoring of Mexico City for the sampling site, we estimated exposure levels for people of different ages and gender. Two endocrine disrupting compounds, the phthalate esters DEHP and DnBP, were found on the particles in higher concentrations during the warmer months of the year. The highest concentration was reported for DEHP (229.7µg/g of particles) in PM2.5 collected in May 2013. After calculations of the DEHP concentration in the atmosphere, and using the respiratory flow rate, we determined males were potentially exposed to larger quantities of DEHP, reaching up to 18ng/8h in April 2013. Despite the concentrations of phthalates seem to be rather small, a comprehensive characterization of its presence is necessary in order to evaluate the overall exposure to these compounds, providing a clear view of exposure on children, adolescents and pregnant women.