Purpose The present report describes the distribution of breast milk and urinary free and total bisphenol A (BPA) concentrations, from 27 post-partum 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 non-parametric 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.

WHAT'S KNOWN ON THIS SUBJECT: Bisphenol A (BPA) is an environmental endocrine disruptor that can leach from polycarbonate plastics and epoxy resins, leading to widespread exposure. Fetal and early postnatal periods are particularly vulnerable to exposure to BPA. WHAT THIS STUDY ADDS:This study identified medical devices as a potential source of exposure to BPA among premature infants in the NICU, even when efforts to reduce polycarbonate plastics were taken. abstract OBJECTIVES: To determine whether nutritional intake and medical devices are bisphenol A (BPA) exposure sources among premature infants in the NICU. METHODS:Mothers and their premature infants cared for in the NICU for the past 3 days were recruited for this exposure assessment study. Forty-three mothers contributed 1 nutrition sample (breast milk or formula) to characterize the infant' s intake. Two urine samples (before and after feeding) were collected from each of 55 infants. Medical device use was categorized as "low" or "high" based on the number and invasiveness of devices used. BPA urinary concentrations used as a biomarker to estimate BPA exposure were measured by online solidphase extraction, high performance liquid chromatography, isotope dilution, tandem mass spectrometry. Nonparametric equivalence tests, intraclass correlations, and hierarchical linear mixed-effects models were conducted.RESULTS: Breast milk and formula samples did not differ in total BPA concentration nor did infants' median urinary concentration of total BPA before or after feedings. However, the median urinary total BPA concentration among infants who required the use of 4 or more medical devices in the past 3 days was significantly higher (36.6 mg/L) than among infants who required the use of 0 to 3 devices (13.9 mg/L). The calculated BPA exposures are lower than the US Environmental Protection Agency reference dose, but considerably higher (16-to 32-fold) than among infants or children from the general population. CONCLUSIONS:The number of medical devices used in the past 3 days, but not nutritional intake, was positively associated with exposure to BPA. Pediatrics 2013;131:483-489 AUTHORS: