"Quantitative identification of unknown exposure pathways of phthalates based on measuring their metabolites in human urine"

Kikuo Yoshida¹, Hiroaki Itoh², Shigeki Masunaga², 

¹National Institute of Advanced Industrial Science and Technology
²Yokohama National University 

  ENVIRONMENTAL SCIENCE & TECHNOLOGY,  Vol.41 No.13 pp4542-pp4547 (2007/6)

---

Abstract

Humans are exposed to ubiquitous phthalates via multiple pathways. While the Japanese national government has regulated the use of di(2-ethylhexyl)phthalate (DEHP) and excluded several other phthalates from its regulation based on some of them, it is unclear whether such past assessment fully assessed total human exposure to phthalates. In the present study, we recruited voluntary participants, and measured the urinary concentrations of phthalate metabolites. We then derived the daily intakes of their respective phthalates in Japan. Exposures to dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate via diet and air accounted for less than half of their respective total exposures. On the other hand, it appears that dietary intake was more predictive for the total exposure to n-butyl-benzyl phthalate and DEHP. The probabilities that the lognormal distribution of each phthalate daily intake exceeds the corresponding tolerable daily intake were estimated to be less than 10−4. 

Keywords

フタル酸エステル，尿中代謝物，摂取量，暴露経路