Patterns, Variability, and Predictors of Urinary Triclosan Concentrations during Pregnancy and Childhood

Abstract

Exposure to triclosan, an antimicrobial used in many consumer products, is ubiquitous in the United States, yet only limited data are available on the predictors and variability of exposure, particularly in children. We examined the patterns, variability, and predictors of urinary triclosan concentrations in 389 mother-child pairs enrolled in the Health Outcomes and Measures of the Environment Study from 2003 to 2006. We quantified triclosan in 3 urine samples collected from women between 16 weeks of pregnancy and birth and 6 urine samples collected from children between the ages of 1-8 years. For maternal and child samples, we calculated intraclass correlation coefficients (ICCs) to assess triclosan reproducibility and identified sociodemographic predictors of triclosan. Among 8 year old children, we examined associations between triclosan and personal-care product use. We detected triclosan in >70% of urine samples. Median maternal triclosan varied across pregnancy from 17 to 11 ng/mL, while in children, median concentrations increased from 3.6 to 17 ng/mL over the first 4 years of life, declining slightly at later ages. Triclosan reproducibility was fair to good during pregnancy and for child samples taken weeks apart (ICCs = 0.4-0.6) but poor for annual child samples (ICCs = 0.2-0.4). Triclosan was 66% (95% CI: 29-113) higher in 8 year olds using hand soap compared to nonusers and increased monotonically with hand-washing frequency. Toothpaste use in children was also positively associated with triclosan. Our results suggest that urinary triclosan concentrations have modest stability over weeks to months; children are exposed to triclosan through the use of some personal-care products.

Figures

Figure 1

Box-and-whisker plots of unstandardized (ng/mL) and creatinine-standardized (μg triclosan/g creatinine) urinary triclosan concentrations in HOME Study mothers and children.

Figure 2

Intraclass correlation coefficients (ICCs) of HOME Study (A) maternal and (B) child urinary triclosan concentrations.

Figure 3

Percent change (with 95% confidence interval) in HOME Study (A) mothers' and (B) children's urinary triclosan concentrations per interquartile range increase in serum cotinine, urinary BPA, and urinary phthalate metabolite concentrations. For mothers, measurements at 16 and 26 weeks were used; for children, measurements at the 1–5 and 8 year visits were used except for mean serum cotinine, which was only measured at ages 1–3 for children. Urinary phthalate metabolites included MCPP, MnBP, MiBP, MEP, MBzP, and the sum of DEHP metabolites (MEHP + MEHHP + MEOHP + MECPP). Models in panel A were adjusted for mother's race, age, education, parity, marital status, household income, and creatinine z-score. Models in panel B were adjusted for child's race, sex, age, household income, mother's education, and creatinine z-score.

Figure 4

Adjusted percent difference in the HOME Study children's urinary triclosan concentrations at 8 years of age according to parent-reported child frequency of hand washing. Adjusted for child's race, sex, age, household income, mother's education, and creatinine z-score.