BACKGROUND:Exposure to triclosan and triclocarban has been proposed to disrupt estrogen metabolism, but relevant human studies remain limited, especially among pregnant women.
METHODS:A cross-sectional study was conducted in 432 pregnant women aged 18-42 years selected from the Wenzhou Mother and Child Cohort Study. Urinary concentrations of triclosan, triclocarban, and three estrogens (estrone (E1), 17β-estradiol (E2), and estriol (E3)) were measured by liquid chromatography coupled to mass spectrometry. The associations of urinary triclosan and triclocarban with urinary estrogens were analyzed using linear regression models and restricted cubic spline analysis.
RESULTS:Triclosan and triclocarban were detected in 60.2 % and 25.9 % of urine samples, respectively. After trichotomizing urinary triclocarban concentrations based on limit of detection and median of urinary creatinine-corrected concentration among positive samples, pregnant women in tertile 3 showed a higher urinary E1 concentration in the adjusted model (regression coefficient (β) = 0.26, 95 % confidence interval (CI): 0.01, 0.52, p = 0.045). After stratified by pregnancy trimester, for pregnant women in the first trimester of pregnancy, those in tertile 2 of urinary triclosan had a marginally higher urinary E1 concentration (β = 0.25, 95 %CI: 0.03, 0.47, p = 0.029) and those in tertile 3 showed lower urinary concentrations of E1 (β = -0.28, 95 %CI: 0.50, -0.05, p = 0.017) and E2 (β = - 0.19, 95 %CI: 0.36, -0.01, p = 0.034). For pregnant women in the second/third trimester of pregnancy, those in tertile 3 of urinary triclosan had a marginally higher urinary E1 concentration (β = 0.26, 95 %CI: 0.04, 0.55, p = 0.090). An approximately inverted U shape was observed for the association of urinary triclosan with E1 and E2 in the first trimester of pregnancy.
CONCLUSIONS:Exposure to triclosan and triclocarban may disrupt estrogen metabolism during pregnancy with a difference by pregnancy trimester and some non-monotonic dose responses.