On December 8, the California Office of Environmental Health Hazard Assessment (OEHHA), the state agency in charge of implementing Proposition 65 (Prop. 65), issued a guidance letter providing clarity about Prop. 65 warnings for Bisphenol S (BPS) in receipt paper and shipping labels, an issue that has been at the forefront of Prop. 65 enforcement this year.
Prop. 65 requires businesses with 10 or more employees to provide a “clear and reasonable” warning before exposing individuals in California to any listed chemical that may cause cancer or reproductive harm unless the exposure falls within certain statutory or regulatory exceptions. BPS was added to the Prop. 65 list of chemicals on December 29, 2023, with enforcement beginning a year after that. BPS is commonly used as a coating on thermal paper—the kind used for receipts and shipping labels. Since early 2025, hundreds of businesses have received Notices of Violation for failure to provide clear and reasonable warnings before knowingly and intentionally exposing individuals to BPS in thermal receipt paper.
Prop. 65 warnings are required in a number of situations, including consumer product exposures. Because thermal paper is not a traditional consumer product (but instead accompanies consumer products), there has been some uncertainty in the regulated community as to which Prop. 65 warning is appropriate for thermal receipt paper and how this warning should be given. OEHHA’s letter answers some of these questions and provides clarity to regulated businesses.
Key Takeaways from OEHHA’s Letter
- Thermal receipt paper or labels containing BPS cause a “consumer product exposure” triggering a Prop. 65 warning obligation even if they merely accompany the purchase of a traditional “consumer product.” Thus, a consumer product Prop. 65 warning is appropriate. The Prop. 65 regulations provide “safe harbor” language that businesses may use to give compliant consumer product warnings.
- The safe harbor warning language may inform customers that the warning is being given for a receipt or label. In fact, OEHHA encourages this, stating that adding language to the warning identifying the receipt or label as the source of BPS is encouraged because it “provides consumers with useful information about the source of the exposure.”
- Consistent with the language of Prop. 65, a warning must be given before an exposure occurs. Therefore, the warning may not be printed on the receipt or label itself. OEHHA notes that placing a warning near or at cash registers may be especially useful and would allow customers to choose an emailed receipt instead of a printed one.
- The retail seller defenses to Prop. 65 apply in the context of BPS in thermal receipt paper and shipping labels, meaning that retailers may potentially avoid liability by promptly taking action following a Notice of Violation.
- Finally, OEHHA recommends that businesses consider not only consumer exposures to BPS, but occupational exposure of any workers handling receipts or labels containing BPS.
While this letter provides some welcome clarity, businesses are well-advised to consult with experienced counsel to navigate the evolving Prop. 65 landscape and minimize exposure to litigation and liability. We are closely following these issues and have significant experience representing clients that have received a BPS Prop. 65 Notice of Violation.
