Reference values and exposure risk of bisphenol A and its substitutes in Taiwan: Taiwan environmental survey for Toxicants (TESTs) 2013–2016

BACKGROUND: Exposure to bisphenol A (BPA) and its substitutes bisphenol F (BPF) and bisphenol S (BPS) poses potential health concern. Following the European Food Safety Authority's 2023 re-assessment of tolerable daily intake for BPA, the exposure risks and reference values of these bisphenols in Taiwan remain unclear. This study aimed to establish the human urinary reference values of BPA and its substitutes and identify exposure-related risk factors using biomonitoring data. METHODS: We analyzed urinary BPA, BPF and BPS in 1964 participants from the Taiwan Environmental Survey for Toxicants (TEST 2013-2016), covering major regions and age groups of the Taiwanese population, and stratified by sex and age (7-11, 12-17, 18-39, 40-64, and ≥65 years). Urinary bisphenol concentrations were quantified using ultraperformance liquid chromatography tandem mass spectrometry. RESULTS: Bisphenol levels were significantly associated with personal care product use, diet, medication, and plastic use (p < 0.001). BPF showed the highest median levels (8.09 μg/g creatinine), followed by BPA (7.71 μg/g creatinine) and BPS (1.93 μg/g creatinine). Adults exhibited significantly higher concentrations of BPA and its substitutes than minors (BPA: 8.89 vs. 5.80; BPF:9.06 vs. 6.32; BPS: 2.18 vs.1.50 μg/g creatinine), with women showing higher BPs levels than men. Bisphenol levels increased with age, peaking in individuals aged ≥ 65 years. Daily intake was highest for BPF across all age groups, exceeding that of BPA and BPS. In contrast, estimated DI and hazard index (HI) were higher among minors than adults (BPA DI: 2.61 vs. 2.15; BPF DI: 2.84 vs. 2.19; BPS DI: 0.71 vs. 0.53 ng/kg bw/day). Using the EFSA 2023 tolerable daily intake (TDI), hazard quotient and index exceeded 1 across all groups, indicating potential health concern. CONCLUSION: Taiwanese residents are exposed to BPA and its substitutes, with women and minors, being at an increased risk of exposure. The findings highlight the need for continued biomonitoring and risk evaluation of bisphenol substitutes to inform evidence-based exposure reduction strategies.