Urinary excretion of parabens in pregnant Japanese women

Urinary excretion of free and total (free plus conjugated) forms of methyl, ethyl, n-propyl and n-butyl parabens (MP, EP, PP and BP, respectively) and their metabolite p-hydroxybenzoic acid were measured for 111 pregnant Japanese women. Frequent detection of parabens and their metabolite indicated that exposure takes place daily for pregnant Japanese women. The estrogenic potency of PP was 20 times higher than those of the other 3 parabens for the present subjects when both abundance in the urine and the relative estrogenic activity of each compound was considered. Detection of free parabens suggested dermal exposure, probably from their inclusion in personal care products. No statistical association was found between the anogenital index (birth weight-adjusted AGD) of male offspring and the concentrations of any parabens in the urine of the mothers suggesting that the parabens were not apparently estrogenically active at the exposure level of the present subjects.

► Concentrations of methyl, ethyl, propyl and butyl parabens and their metabolite were measured in 111 urine samples from pregnant Japanese women.
► Total parabens (conjugated + free) were detected in more than half of the subjects while free forms were detected but less frequently.
► The urinary concentration was related to anogenital distance of the male offspring born to the subjects to find no statistical association.
► Estrogenic/antiandrogenic actions of parabens, if any, may not be overt at this exposure level.