Serial free bisphenol A and bisphenol A glucuronide concentrations in neonates

Objective To determine the balance of metabolism of free bisphenol A (BPA) to the inactive conjugate, BPA glucuronide (BPAG), in neonates. Study design Free BPA and BPAG concentrations were measured in 78 urine samples collected between December 2012 and August 2013 from a cohort of 44 healthy full term (≥37 weeks' gestation) neonates at 2 intervals (3-6 days and 7-27 days of age). A questionnaire was administered at the time of sample collection. Neonates recruited into the study were born in an urban, tertiary care hospital. Results Only BPAG was detected in the urine samples; concentrations ranged from <0.1 μg/L to 11.21 μg/L (median: 0.27 μg/L). Free BPA concentrations were below the limit of quantification of 0.1 μg/L. Age, but not sex or type of diet, was significantly associated with urinary BPAG concentration (P =.002). Conclusions Our results illustrate widespread BPA exposure in healthy full-term neonates and efficient conjugation of BPA to its readily excretable and biologically inactive form (BPAG) as early as 3 days of age. Factors other than type of diet may be important contributors to BPA exposure in neonates.