Many BPA alternatives may not be safer, study reveals

Recent research has raised significant concerns about the safety of alternatives to bisphenol A (BPA), a chemical widely used in plastics and resins, known for its endocrine-disrupting properties. A study, recently published in Environmental Science & Technology, highlights that many substitutes for BPA could be "regrettable" replacements, potentially carrying similar or even different health risks.  

BPA has been linked to various health issues affecting organs such as the brain, heart, and reproductive systems, prompting regulatory actions in the European Union and Switzerland to ban its use in food contact materials. In response to growing health concerns, manufacturers have increasingly turned to alternatives like bisphenol S (BPS) and bisphenol F (BPF). However, these substitutes are structurally similar to BPA, raising questions about their safety.

The study, conducted at the Helmholtz Centre for Environmental Research in Germany, utilized in vitro bioassays to evaluate the hazard potential of BPA and 26 of its alternatives. The research revealed that many of these substitutes activate the estrogen receptor α (ERα), a pathway closely associated with BPA's harmful effects. Notably, compounds such as bisphenol AF (BPAF) and bisphenol Z (BPZ) exhibited comparable potency in this regard.  

Interestingly, while some alternatives with bulky modifications at specific positions on their structure lost estrogenic activity, they triggered activation of the peroxisome proliferator-activated receptor γ (PPARγ)—a receptor not influenced by BPA. This suggests that, although these compounds may seem safer at first glance, they could pose their own risks.  

The researchers also identified mitochondrial dysfunction and neurotoxicity associated with several BPA alternatives, underscoring the complexities in evaluating chemical safety. Among the alternatives studied, 2,2,4,4-tetramethyl-1,3-cyclobutanediols (TMCD) emerged as a more promising candidate, showing no specific activity in any of the tested assays. However, its distinct chemical structure means it cannot serve as a direct substitute for BPA.  

The findings lead the authors to advocate for a re-evaluation of how bisphenols are regulated. They argue that compounds with similar toxicological profiles should not be treated differently merely due to a lack of in vivo data. Instead, they should be assessed collectively as toxicological analogues.  

This research highlights the need for a comprehensive approach to chemical regulation, particularly for bisphenols, which have been flagged as a group of concern in recent reports. The authors emphasize that the methodologies developed in their study could be applied to other chemical classes, enhancing the prioritization and substitution processes for hazardous materials.

As the conversation around chemical safety continues to evolve, this study serves as a crucial reminder that simply replacing one harmful chemical with another structurally similar option may not lead to safer outcomes for public health.    

Source:  

ACS Publications