Bisphenol A concentrations in maternal breast milk and infant urine

Purpose The present report describes the distribution of breast milk and urinary free and total bisphenol A (BPA) concentrations, from 27 postpartum women and their 31 infants, and explores the influence of age, sex, and nutritional source on infant BPA urinary concentration. Methods Both free (unconjugated) and total (free plus conjugated) BPA concentrations from women’s breast milk samples and infants’ urine samples were measured by online solid-phase extraction coupled to high-performance liquid chromatography–isotope dilution tandem mass spectrometry. Descriptive statistics and nonparametric tests of group comparisons were conducted. Results Total BPA was detected in 93 % of urine samples in this healthy infant population aged 3–15 months who were without known environmental exposure to BPA [interquartile range (IQR) = 1.2–4.4 μg/L)]. Similarly, 75 % of the mothers’ breast milk samples had detectable concentrations of total BPA (IQR = 0.4–1.4 μg/L). The magnitude and frequency of detection of free BPA in the children’s urine and the mothers’ breast milk were much lower than the total concentrations. Conclusions Total BPA was detected in 93 % of this healthy infant population aged 3–15 months who are without known environmental exposure to BPA. Neither free nor total BPA urinary concentrations differed significantly by infant’s sex or by nutritional source (breast milk and/or formula) while age group was of borderline significance. There were no significant correlations between free or total BPA concentrations in mothers’ breast milk and their infants’ urine.