Advanced detection of bisphenol A in plastic water bottles using liquid-liquid phase extraction and LC-MS

The release of endocrine-disrupting chemicals (EDCs) can harm humans and wildlife. It is therefore important to monitor bisphenol A (BPA) consumption, an endocrine disruptor commonly found in water from plastic products, and detect BPA at low concentrations for accurate health risk assessments. We present a method for estimating BPA levels in plastic-bottled products that is highly sensitive, precise, and effective. BPA analysis was performed using advanced liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), with multiple reaction monitoring (MRM) on a state-of-the-art Orbitrap mass spectrometry system using negative ionization techniques. To assess the quality of Indian brands of water, we used LC-MS to obtain balanced hydrophilic-lipophilic extracts. Brand water samples showed efficiently separated BPA in 2.35 minutes, with other sources typically taking between 5 and 8 minutes. BPA concentrations, measured within a range of 10 ng mL^-1 to 1 pg mL^-1 with a lower detection limit (LOD) of 0.037 ng mL^-1, were characterized by dynamic linear ranges and corresponding linear equations for each compound. We also evaluated the reproducibility and sensitivity of the detection of BPA in different water samples, including mineral, river, and tap water, with low levels of BPA found in Indian river water (below 4.54 ng mL^-1). Thus, this study explored alternatives to solid phase extraction (SPE) for screening BPA analogs in water samples, and real samples from an Indian supermarket revealed BPA in plastic bottles at concentrations comparable to those described in Europe, the United States, Korea, Japan, and China.