You’ve likely seen BPA-free plastic water bottles and Tupperware in stores and opted to grab those over similar, non-labeled products. You probably didn’t know, however, that those products likely just contain other bisphenols, like BPS or BPAF, instead. Regulating bisphenols, a class of endocrine disrupting chemicals, has been challenging due to “regrettable substitution.” This phenomenon allows companies to truthfully label a product “BPA-free” while misleadingly substituting a harmful chemical (BPA) with an unknown or unforeseen hazardous chemical (BPS). Adequate protection of human health requires regulators to consider how bisphenols as a class can be appropriately restricted.
BPA is one of many Endocrine Disrupting Chemicals (EDCs). EDCs — which also include PCBs, DDT, and Phthalates — interfere with and prevent the binding of natural hormones to their receptors. They can also act as hormone mimics, enhancing the effects of endogenous hormones. The reduction in hormone binding or exaggerated effects of hormones are associated with a slew of health effects including insulin resistance, type 2 diabetes, altered immune response, and altered cardiac functioning. Most notably, the structure of BPA is similar to estradiol (the most potent abundant form of estrogen in the body) and BPA has been shown to accelerate puberty in both girls and boys.
While many scientists agree that BPA is an endocrine disruptor, regulatory agencies around the world have taken different approaches to defining and restricting EDCs. Despite legislative authority to regulate endocrine disrupting toxicity in safety assessments of products, the United States regulatory bodies have failed to keep up with the volume of EDCs in commerce. Humans appear to be exposed to BPA mostly through food packaging, which is subject to premarket approval under the jurisdiction of the U.S. Food and Drug Administration (FDA). The FDA maintains that low levels of BPA exposure are safe for humans. However, the FDA has recognized that low levels of exposure are not safe during infant development and no longer allows BPA-based baby bottles, sippy cups, or packaging for infant formula.
Federal regulatory bodies in the US do not have the authority to regulate classes of chemicals but states may. In 2019, Washington passed the Safer Products for Washington Act which allows large groups of chemicals to be regulated by class rather than the standard chemical-by-chemical method employed by federal agencies in the U.S. This law is unique among US state laws, many of which ban whole classes of chemicals in certain products, because it requires that every five years state public health regulators select groups of chemicals to restrict or eliminate when safer alternatives are available.
On May 31, 2023, Washington State’s Department of Ecology (DoE) adopted a final rule under the Act which banned bisphenol-based drink can liners. The rule defines bisphenol as “a chemical with two phenol rings connected by a single linker atom.” In a supporting report, DoE called out Bisphenol A (BPA) Bisphenol S (BPS), Bisphenol F (BPF), Bisphenol AF (BPAF), and Tetrabromobisphenol A (TBBPA) as not meeting the minimum criteria for safer alternatives to be used in beverage can linings.
Similar to Washington State, the European Union (EU) has taken a strict approach to regulating EDCs. On June 1, 2007, the Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) regulation entered into force. Substances that are added to REACH’s substances of very high concern list (the “blacklist”) are required to be phased out from use in the EU. However, REACH still requires a chemical-by-chemical determination of safety rather than a class-based approach.
The most aggressive move to regulate EDCs came on June 12, 2024, when an EU Expert Committee approved a proposal to ban BPA in all food contact materials to protect consumers across all age groups. Even further, all other bisphenols that elicit similar endocrine disrupting effects are included in the ban, with explicit references to BPS and BPAF included. The ban, which requires manufacturers to transition to safer chemicals in single-use and reusable materials, will enter into force at the end of 2024.
There are fair criticisms of class-based regulations of chemicals. Industry has been extremely resistant to the idea of a class-based approach to regulating chemicals. Manufacturers argue that the proper regulatory framework would exclude chemicals that are deemed safer within a group and allow for essential uses of banned chemicals when safer alternatives are not available. Additionally, how regulators define “like” chemicals is contentious and continues to play a major role in filtering which chemicals are and are not included in a ban. For example, bisphenol A diglycidyl (BADGE) has a molecular structure similar to BPA but does not fit the current class-based definition of bisphenols in Washington State or the EU. Despite eliciting similar health effects to other bisphenols, its use continues to abound in epoxy resin glues, paints, and coatings.
As more data is collected on the harmful effects of endocrine disruptors, regulators must keep up with the current science. This includes a reevaluation of class-based approaches to regulating chemicals. Both Washington State and EU frameworks for regulating bisphenols provide possible approaches to reducing the risk of regrettable substitution of harmful chemicals in consumer products. Despite fair industry criticism of over-regulation, there are more proactive ways to regulate chemicals by class without unnecessarily banning less harmful molecules. Scientific understandings of structurally similar chemicals should drive regulators to appropriately tailor regulations to minimize the negative health effects of EDCs.
Jessica Samuels is a third-year dual degree law and public health student (J.D./MPH 2025). Her research interests include genetics, environmental health sciences, novel biotechnologies, and the FDA regulatory process. She has previously published work on the accuracy of ultrasound in predicting malignant ovarian masses. At HLS, Jessica is co-president of the Harvard Health Law Society.
