Advisories November 22, 2024

Environment, Land Use & Natural Resources Advisory: Addition of Bisphenol S (BPS) to Proposition 65 List Has Sweeping Implications for Industry

Executive Summary
Minute Read

Our Environment, Land Use & Natural Resources Group discusses the California Office of Environmental Health Hazard Assessment’s addition of bisphenol S (BPS) to the Proposition 65 list of reproductive toxicants.

  • The change will significantly impact the retail, food and beverage, pulp and paper, industrial manufacturing, and personal care product industries
  • Businesses should assume that private enforcers will serve notices of violation for any detectable amount of BPS
  • The addition of BPS to the Proposition 65 list is effective December 29, 2024

On December 29, 2023, the California Office of Environmental Health Hazard Assessment (OEHHA) added bisphenol S (BPS) to the Proposition 65 list of chemicals known to cause reproductive toxicity. The listing becomes effective on December 29, 2024, which means companies must begin displaying Proposition 65 warnings for BPS within a few weeks or reformulate products so no warning is required. Given the current use of BPS in millions of products, the listing will have sweeping implications for businesses in the retail, food and beverage, pulp and paper, industrial manufacturing, and personal care product industries.

Background on Proposition 65

California’s Proposition 65, formally known as the Safe Drinking Water and Toxic Enforcement Act of 1986, requires businesses to provide warnings before exposing individuals to chemicals known to the state of California to cause cancer, birth defects, or reproductive harm. Proposition 65 requires California to publish a list of these chemicals, which must be updated at least once a year. The list has grown to include approximately 900 chemicals since it was first published in 1987.

Proposition 65 imposes civil penalties of up to $2,500 per violation. The statute also provides that any company that “threatens to violate” the warning requirement may be “enjoined in any court of competent jurisdiction.”

The California attorney general, any district attorney, and certain city attorneys are authorized to enforce Proposition 65. In addition, any individual (even someone who has not suffered harm or ever used the product at issue) may bring a private enforcement action. The private enforcer must first serve a 60-day notice of violation on the alleged violator before proceeding to file a lawsuit. These private enforcers take home 25% of all civil penalties imposed as a “bounty” for their efforts, and their attorneys routinely recover their fees.

These “bounty hunter” lawsuits often result in settlements, which include civil penalties, attorneys’ fees, and injunctive relief (such as displaying Proposition 65-compliant warnings or agreeing to reformulate a product).

California Places BPS on the Proposition 65 List

The listing of BPS as a reproductive toxicant under Proposition 65 will take effect one year from the date of addition – December 29, 2024. This grace period is intended to give businesses time to evaluate their products and operations to determine whether compliance measures, such as warning labels, are required.

Notably, OEHHA has not yet established a “safe harbor level” for BPS. A safe harbor level is a threshold below which a business is exempt from Proposition 65 warning requirements. These levels provide clarity and protection for businesses. Without a safe harbor level to guide them, businesses should assume that private enforcers will serve notices of violation if there is any detectable amount of BPS. The burden would then shift to the alleged violator to prove the product does not require a warning, including through performance of quantitative risk assessments and exposure assessments.

Products That May Contain BPS

BPS is part of polyethersulfone plastic, which is used to make hard plastic items and synthetic fibers for clothing and other textiles. It is a common replacement for bisphenol A (BPA) in polycarbonate plastics, epoxy resins, and thermal paper.

BPS may be found in some of the following products.

Consumer goods

  • Food and beverage containers, including plastic bottles and the linings of food and beverage cans
  • Food utensils
  • Baby bottles, sippy cups, and other products marketed for infants and children
  • Personal care items, such as cosmetics packaging
  • Microwave-safe dishes and containers
  • Parts of electronics, such as screens for mobile phones and calculators

Industrial and commercial products

  • Industrial coatings and adhesives
  • Protective linings for metal cans and pipes
  • Heat-resistant parts in automobile engines, industrial machinery, medical equipment, and other applications

Paper products

  • Cash register receipts
  • Tickets (parking tickets, lottery tickets, etc.)
  • Shipping labels
  • Prescription labels

Clothing and textile products

  • Sportswear
  • Socks
  • Raingear
  • Blankets
  • Curtains
  • Furniture upholstery

Implications for Businesses

Given the widespread use of BPS, businesses across a range of industries need to take action to determine whether their products comply with Proposition 65, assess the need to reformulate or display warnings, evaluate potential affirmative defenses, and determine the risk of private enforcement.

Potential actions businesses may take include:

  • Conducting product assessments: Often, companies may not even know if BPS is present in their products – or if it is, how it got there. Review product formulations and materials to identify potential BPS content. Testing for BPS may be necessary to determine exposure levels. Evaluate whether to perform testing in coordination with counsel.
  • Evaluate exposure scenarios: Without a safe harbor level for BPS, companies face significant compliance challenges. Work with consultants to perform risk and exposure assessments to determine whether products require Proposition 65 warnings for BPS.
  • Supply chain issues: Assess the supply chain to determine whether any products may contain BPS; companies may consider requesting supplier certifications, testing, and data sheets.
  • Product reformulation: Companies may seek to reformulate their products to eliminate BPS to avoid Proposition 65 warnings. They should understand the cost of reformulation and whether it would require significant changes to manufacturing processes and supply chain agreements. Companies should not replace BPS with other bisphenols listed on the Proposition 65 list, like BPA.
  • Provide warnings: If businesses determine a Proposition 65 warning is required, they need to determine the appropriate content of the warning and method of transmission. OEHHA is updating the Proposition 65 safe harbor warning language, as discussed in our prior advisory, and businesses should stay abreast of these regulatory changes. Businesses may also need to evaluate whether to provide written notification to downstream entities that their products require warnings.
  • Defense and indemnification: Ensure your company has contractual protection in the event of litigation, including defense and indemnification provisions in supplier agreements.

The addition of BPS to the Proposition 65 list becomes effective in a few weeks, which will open the floodgates to private enforcement actions. Businesses across industries must act now to evaluate their products, understand their compliance obligations, and mitigate risks associated with this new listing. With proactive planning, companies can navigate the complexities and uncertainties surrounding this new listing. 


You can subscribe to future advisories and other Alston & Bird publications by completing our publications subscription formIf you have any questions, or would like additional information, please contact one of the attorneys on our Environment, Land Use & Natural Resources Team.

Meet the Authors
Media Contact
Alex Wolfe
Communications Director

This website uses cookies to improve functionality and performance. For more information, see our Privacy Statement. Additional details for California consumers can be found here.