Infant Exposure to Bisphenol A Can Be Quantitatively Assessed by a Simply Improved High-Performance Liquid...

To quantitatively measure trace levels of bisphenol A (BPA) in infant urine, a simply improved high-performance liquid chromatography (HPLC)-tandem mass-spectrometry method was developed and validated. In the present work, a ZORBAX SB-C₁₈ column (2.1 × 30 mm, 3.5 μm) was used for trapping and isolating BPA from the HPLC mobile phase. The result showed that the trapping column can provide effective separation from the background BPA to the sample BPA. This method has a limit of detection (LOD) of 0.048 μg/L, spiked recoveries 85.4% (0.50 - 10.0 μg/L), and relative standard deviations of 1.8 - 15.9%. By using its low-LOD advantage, we firstly reported that Chinese infants (n = 48 with age <6 months) have been ubiquitously exposed to BPA (detection frequency of 93%) with an median level of 0.13 μg/L (ranging from below LOD to 5.04 μg/L).