Comparisons of urinary phthalate metabolites and daily phthalate intakes among Japanese families

Abstract

1We measured urinary phthalate metabolites, including di-n-butyl phthalate (DnBP), di-isobutyl 2 phthalate, benzyl butyl phthalate (BBzP), and di(2-ethylhexyl) phthalate (DEHP), from 178 school-3 aged children and their 284 family members using gas chromatography-mass spectrometry, and we 4 calculated daily phthalate intakes. The highest median levels of phthalate metabolites were for 5 mono-isobutyl phthalate in all participants except schoolchildren, where the highest levels were for 6 mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP). Comparing the schoolchildren with their parents, 7 the schoolchildren had significantly higher urinary metabolites for MEOHP, mono-(2-ethyl-5-8 carboxypentyl) phthalate, and ΣDEHP. Regarding daily intakes, the schoolchildren had significantly 9 higher daily intakes of DnBP, BBzP, and ΣDEHP. All phthalate metabolite and sums of metabolite 10 levels in the schoolchildren were positively correlated with their mothers' levels, except for MEHP, 11 whereas fathers were less correlated with their children. The DEHP intake in this study was higher 12 than that of most other studies. Moreover, 10% of the children and 3% of the adults exceeded the 13 Reference Dose (RfD) value (20 g/kg/day) of the U.S. Environmental Protection Agency, which 14 indicates that it is important to focus on children's DEHP exposure because the children exceeded 15 the RfD more than adults among the same families who shared similar exposure sources. Our 16 results will contribute to considerations of the regulations for some phthalates and the actual 17 phthalate exposure levels in the Japanese population. 18 3

Effects of Gender on the Association of Urinary Phthalate Metabolites with Thyroid Hormones in Children: A Prospective Cohort Study in Taiwan

“…The geometric median concentration of MEHP in our study was similar to that reported in an American study on children [24]. The sum of DEHP metabolites was considerably lower in our study than in those conducted in Australia [25], Greece [26], Denmark [27], and Japan [28] and other studies conducted in Taiwan after a food scandal [29]; however, the results were similar to those obtained in China [30]. The MnBP concentration in our study was markedly higher than that reported in a Japanese study [28] and mildly lower than that reported in a Chinese study [30].…”

“…The sum of DEHP metabolites was considerably lower in our study than in those conducted in Australia [25], Greece [26], Denmark [27], and Japan [28] and other studies conducted in Taiwan after a food scandal [29]; however, the results were similar to those obtained in China [30]. The MnBP concentration in our study was markedly higher than that reported in a Japanese study [28] and mildly lower than that reported in a Chinese study [30]. The sum of DBP metabolite concentrations in our study was similar to that reported in America [24] but lower than that reported in Australia [25], Denmark [27], Germany [21], and Greece [26].…”

Analytical method for urinary metabolites as biomarkers for monitoring exposure to phthalates by gas chromatography/mass spectrometry

“…The results obtained were compared with those for previous studies targeting Japan. The levels of the urinary concentrations of MMP, MEP, MiBP, MnBP, MBzP and MECPP in this study approximately agreed with those from the previous reports, namely 6.5–33 μg/L as the median of urinary concentrations for MMP, 6–18 μg/L for MEP, 8.4 μg/L for MiBP, 15.7–60.0 μg/L for MnBP, 2.4–18.3 μg/L for MBzP and 7.5–44.1 μg/L for MECPP (Bamai et al, ; Guo et al, ; Itoh, Yoshida, & Masunaga, ; Kato et al, ; Kondo et al, ; Suzuki et al, ). On the other hand, urinary McHP had not been detected previously in Japanese subjects, and furthermore, there was no detection of urinary McHP by GC/MS.…”

Adverse child health impacts resulting from food adulterations in the Greater China Region

“…Approximately 10% of the children in that study ( n = 178, age 3–12) exceeded the reference dose of 20 µg kg −1 day −1 . Interestingly, pre‐school children (age ≤ 6) often show higher daily estimated intakes than school children (age 7–14), as reported by studies in Japan, Taiwan and Germany . Most intake of phthalate is from food, but the researchers believed that playing on the ground, lying down near plastic carpet and mouthing some plastic items such as toys result in pre‐school children having relatively higher exposure than school children .…”

“…Most intake of phthalate is from food, but the researchers believed that playing on the ground, lying down near plastic carpet and mouthing some plastic items such as toys result in pre‐school children having relatively higher exposure than school children . Furthermore, a relatively higher rate of metabolism of phthalate is found in pre‐school children than in school children as well as other age groups, so metabolism of phthalate may be an age‐dependent process …”