Urinary Phenol Metabolites Among Pregnant Women

Abstract

ISEE-369 Objective: Phenols and their metabolites are frequently detected in human biological fluids, suggesting prevalent exposure to the parent environmental agents. Little information is available regarding these chemicals with respect to variability in their concentrations and their relationships with genetic susceptibility, age, and socioeconomic factors. We characterized phenols in urine and associations with the UDP-glucuronosyltransferase 2B7 (UGT2B7) His268Tyr polymorphism and population characteristics as predictors of their concentrations. Material and Methods: Nine phenolic metabolites were measured in 367 urine samples from pregnant women in a New York City cohort. Multivariate analyses were conducted to identify predictors of phenols, including genetics, ethnicity, socioeconomic status, and use of consumer products in relation to metabolite concentrations. Results: Bisphenol A (BPA), 2-hydroxy-4-methoxybenzophenone, triclosan, and 2,4- and 2,5-dichlorophenol (DCP) were detected in at least 78% of samples. Concentrations of 2,5-DCP (median 52.9 μg/L) were above the 75th percentile of women in NHANES (1999–2000), with an adjusted geometric mean of 165 μg/L for mothball users. Differences by race/ethnicity were seen in 2,4-DCP, 2,5-DCP, and 4-tert-octylphenol concentrations. UGT2B7 Tyr268 allele carriers had lower BPA and triclosan metabolite urinary concentrations than those who were not carriers. Conclusions: This study is the first systematic evaluation of phenolic metabolites in pregnant women. Five of the 9 metabolites were detected frequently. Human UGT2B7 was seen for the first time to participate in metabolism of 2 of these chemicals.