Bisphenol a and its chlorinated derivatives in human colostrum.

The health effects related to bisphenol A (BPA) and its exposure sources have undergone extensive investigation, but no consensus has been reached. Hitherto, the major source of human BPA exposure considered in the literature remains food-contact material. However, the chlorine present in drinking water may react with BPA to form chlorinated derivatives (ClxBPA), which have indeed been shown to have a heightened level of estrogenic activity. In this study, we have evaluated colostrum concentrations of BPA and ClxBPA in order to confirm our hypothesis according to which BPA water contamination leads to ClxBPA human exposure. BPA and its ClxBPA were assessed through online solid-phase extraction coupled to ultra high-performance liquid chromatography tandem mass spectrometry (SPE-UPLC-MS/MS) using the isotope dilution method in the colostrums of 21 women who had completed a water exposure questionnaire. BPA was detected in 19 colostrums and its ClxBPA in 21 colostrums. Mean concentrations were 1.87 ± 1.38 ng mL(-1) (n = 19) for BPA, 1.87 ± 1.23 ng mL(-1) (n = 7) and 1.56 ± 0.74 (n = 18) ng mL(-1) for 2,2'-Cl2BPA and 2,6-Cl2BPA, respectively, and 0.68 ng mL(-1) (n = 1) for trichloro-BPA. These findings confirm our hypothesis that ClxBPA should be taken into account in human health risk assessment.

Reliable quantification of bisphenol A and its chlorinated derivatives in human breast milk using UPLC-MS/MS method.

Bisphenol A is a widespread industrial chemical which over the past decade has demonstrated its toxicity as an endocrine disruptor. Chlorine present in drinking water may react with bisphenol A to form chlorinated derivatives, which have demonstrated a heightened level of estrogenic activity. In this work, we have comprehensively validated a method using on-line SPE-UPLC-MS/MS and isotope dilution quantification to measure bisphenol A and its chlorinated derivatives in human breast milk according to accepted guidelines. Deutered bisphenol A was used as internal standard. The matrix calibration curve ranged from 0.40 to 6.40 ng/mL for each of the target compounds and provided good linearity (r²>0.99).This method was precise (the intra and inter-day coefficient of variation was <20% at two different concentrations (0.40 and 3.20 ng/mL) and accurate (recovery ranged from 81% to 119%). The limits of detection obtained for BPA and its chlorinated derivatives ranged from 0.01 to 0.09 ng/mL. The limit of quantification for all the compounds validated at 0.40 ng/mL when using 500 µL of milk was found to be suitable for the concentration existing in real samples. The analytical method developed in this study is in accordance with the requirements applicable to biomonitoring of BPA and its chlorinated derivatives in human breast milk.

Quantification of bisphenol A, 353-nonylphenol and their chlorinated derivatives in drinking water treatment plants.

Bisphenol A (BPA) and nonylphenols (NP) are of major concern to public health due to their high potential for human exposure and to their demonstrated toxicity (endocrine disruptor effect). A limited number of studies have shown that BPA and NP are present in drinking water. The chlorinated derivatives that may be formed during the chlorination step in drinking water treatment plants (DWTP) exhibit a higher level of estrogenic activity than their parent compounds. The aim of this study was to investigate BPA, 353NP, and their chlorinated derivative concentrations using an accurate and reproducible method of quantification. This method was applied to both surface and treated water samples from eight French DWTPs producing from surface water. Solid-phase extraction followed by liquid chromatography-tandem mass spectrometry was developed in order to quantify target compounds from water samples. The limits of detection ranged from 0.3 to 2.3 ng/L for BPA and chlorinated BPA and from 1.4 to 63.0 ng/L for 353NP and chlorinated 353NP. BPA and 353NP were found in most analyzed water samples, at a level ranging from 2.0 to 29.7 ng/L and from 0 to 124.9 ng/L, respectively. In most of DWTPs a decrease of BPA and 353NP was observed between surface water and treated water (36.6 to 78.9 % and 2.2 to 100.0 % for BPA and 353NP, respectively). Neither chlorinated BPA nor chlorinated 353NP was detected. Even though BPA and 353NP have been largely removed in the DWTPs studied, they have not been completely eliminated, and drinking water may consequently remain a source of human exposure.