An overlooked source of inhalational and dermal exposure to bisphenol A and its chlorinated derivatives in disposable...

The presence of emerging and toxic chlorinated bisphenol A derivatives (Cl_xBPA) in disposable face masks (DFMs) remains unconfirmed. A total of 123 DFMs of various types, sourced primarily from China with additional samples from other Asian regions, North America, and Europe were analyzed. The results illustrated bisphenol A (BPA) was detected in all samples, while 3-monochloro bisphenol A (MCBPA) and 3,3',5,5'-tetrachloro-bisphenol A (TCBPA) were found in over 65% of DFMs. BPA exhibited the highest concentrations (geometric mean: 11.6 ng g^-1), followed by TCBPA (0.0446 ng g^-1), MCBPA (0.0234 ng g^-1), 3,3'-dichlorobisphenol A (DCBPA-1, 0.0179 ng g⁻¹), 3,3',5-trichloro-bisphenol A (TriCBPA, 0.0169 ng g^-1), and 3,5-dichloro bisphenol A (DCBPA-2, 0.0142 ng g^-1). Notably, the proportion of DFM samples in which at least one Cl_xBPA congener was detected reached 92.7%, indicating the widespread occurrence of Cl_xBPA in DFMs. The concentration levels of BPA and Cl_xBPA varied by mask material but not between adult and toddler masks or across production regions. Exposure assessment indicated that occupational users and toddlers face higher BPA and Cl_xBPA exposure risks, particularly when using N95 and disposable activated carbon masks. Given the reported toxicological effects of Cl_xBPA, the health risks posed by these emerging contaminants deserve further attention.