Urinary excretion of phthalate metabolites in 663 children after attendance of daycare centers compared with tolerable daily intake of phthalates

摘要

Background In former studies it was hypothesized that high concentrations of phthalates in settled dust of daycare centers are associated with high body burden of phthalate metabolites in children. There is concern about probable health effects among children staying in day care centers with high levels of phthalates in dust. Aims / Methods Urine samples of 663 children (2-6 y) from 63 daycare centers in Germany were collected after they attended the facilities. We analyzed 11 phthalate metabolites in the urine of the children and back-calculated daily intake using medians and 95th percentiles of metabolite concentrations. Additionally we obtained 150 urine samples from a representative subgroup of our collective on Monday mornings at home. Moreover, room air samples and settled dust were analyzed for the presence of 15 phthalate diesters (see also data presented by Fromme et al.). Results Compared with tolerable daily intake (TDI) values recommended by scientific institutions, the share of the high total intake scenario was 72% for DiBP (di-isobutyl phthalate), 58% for DnBP (di-n-butyl phthalate), 31% for DEHP (di-2-ethylhexyl phthalate), and 12% for DiNP (di-isononyl phthalate). For BzBP (benzylbutyl phthalate) and DEP (diethyl phthalate), only 1-2% of the TDI was reached. Some children exceeded the TDI for DiBP (2.7%), DnBP and DEHP (0.2%), DiNP (0.6%) after their stay in the daycare center. For mostly all metabolites the levels in the morning urine samples were higher by a factor between 1.2 and 1.8. Conclusions Based on urinary phthalate metabolite excretion the attendance of children in German day care center is not associated with unhealthy additional phthalate intake. Nevertheless it seems to be necessary to reduce the exposure of children especially to DiBP, DnBP and DEHP. We found no indications that the higher concentrations of phthalates in the dust of daycare centers were a reliable indicator of intake for the children attending these facilities.