Human Biomonitoring of Di(2-ethylhexyl) terephthalate in Portuguese Children

摘要

Di(2-ethylhexyl) terephthalate (DEHTP) is used as a substitute for di(2-ethylhexyl) phthalate (DEHP), an ortho-phthalate based plasticizer that is classified and labeled due to its toxicity to reproduction. Due to the ongoing substitution process, increasing DEHTP exposures of the general population seem likely. Previous HBM studies have shown that children are exposed to plasticizers to a higher degree than adults. For this study, we obtained 107 spot urine samples of Portuguese children (55 girls and 52 boys, aged 4-17) collected in 2014/2015. 68 of these children were classified as overweight/obese according to the body mass index and received specific nutritional guidance. The other 39 children were normal weight and did not receive any specific nutritional guidance. The samples were analyzed for the specific sidechain-oxidized monoester metabolites of DEHTP (5OH-MEHTP, 5oxo-MEHTP, 5cx-MEPTP and 2cx-MMHTP) by a previously published online-SPE HPLC-MS/MS method with isotope dilution. We detected the main specific metabolite 5cx-MEPTP in almost all samples (98 % >LOQ) with a median concentration of 4.4 μg/L (maximum concentration 2220 ug/L). Compared to the, so far, only existing data of a pilot biomonitoring study with 34 German adults (median 0.9 ug/L, maximum: 38.7 ug/L), the levels determined in this study were higher. The other DEHTP metabolites correlated well with 5cx-MEPTP but were detected at lower levels and rates. The concentrations of 5cx-MEPTP in overweight/obese children with specific nutritional guidance (median 3.1 μg/L) Were lower compared to normal weight children (median 5.2 ug/L) but not significantly different (Mann-Whitney-U; p=0.11). Gender specific differences in metabolite levels could not be observed. With this study we provide a first data set documenting the omnipresent DEHTP exposure of the participating Portuguese children.