In 2015, a group of NGOs filed a petition with the U.S. Consumer Product Safety Commission (CPSC), asking CPSC to ban additive, non-polymeric organohalogen flame retardants (OFRs) in four product categories: infant, toddler, or children’s products; upholstered furniture; mattresses; and plastic electronics’ casings. The petitioners argued that the entire chemical class is toxic and poses a risk to consumers and that the CPSC should ban them under the Federal Hazardous Substances Act (FHSA). However, a new report from the National Academies of Sciences, Engineering, and Medicine (NAS) offers the latest scientific assessment: OFRs “cannot be treated as a single class for hazard assessment although they can be divided into subclasses based on chemical structure, physical and chemical properties, and predicted biologic activity.”

As we previously reported in 2015, after reviewing the petition and evaluating the available data, CPSC staff submitted a detailed briefing package to the Commission recommending that it deny the petition for lack of evidence. The FHSA does require evidence-based rules as a statutory matter (15 U.S.C. §1262(f)-(i)). However, the Commission majority rejected staff’s recommendation to deny the petition. A majority of Commissioners instead initiated a rulemaking and attempted to overcome staff’s objection by proposing a chronic hazard advisory panel, or CHAP, to study OFRs as a class and make recommendations for rulemaking. A majority of the Commission also voted to issue “non-binding guidance,” warning consumers about the hazards it believed may be associated with OFRs.

The NAS was asked to first develop a scoping plan for the OFR CHAP to assess the potential hazards of some or all OFRs. This report concludes the first step in this process.

Rulemaking under the FHSA must be science-based, but, as the NAS report notes, evaluating chemicals one by one is a common frustration for scientists:

One of the biggest challenges for the risk-assessment community is how to move from traditional chemical-by-chemical approach to analyses that evaluate multiple chemicals together. The primary problems with this approach are that chemicals on which data is insufficient are typically treated as not hazardous, that untested chemicals are often substituted for hazardous chemicals, and that cumulative exposure and risk are often ignored … the number of chemicals in use today demands a new approach to risk assessment, and the class approach is a scientifically viable one.

Thus, while NAS felt that grouping chemicals by class may be appropriate in certain circumstances, the groupings must make sense based on chemical structure, function, and other factors.

NAS first studied whether OFRs could be treated as a single class “by identifying known OFRs and other structurally related organohalogen compounds.” OFRs cannot be lumped into a single category for hazard assessment, the NAS report says, since OFRs cannot be distinguished from other physically similar chemicals. In addition, OFRs do not have a common chemical structure or predicted biologic activity and therefore cannot be treated as a single class. However, they can be assessed and regulated on the basis of shared properties into groups. In this case, the NAS identified 14 subclasses of OFRs that may be evaluated as separate groups, but rejected the premise that all OFRs should be treated identically.

The thoughtful approach of the NAS report reflects a welcome return to a focus on facts and science as the underpinning of potential chemical regulation, as required under the FHSA. The report should be thoroughly evaluated by CPSC staff and Commissioners before proceeding with a CHAP. The NAS report’s findings confirm CPSC staff’s earlier view that the available science they reviewed several years ago still does not support viewing all OFRs as a single class. From this perspective, it would be appropriate for the current Commission to review and consider rescinding its previous OFR guidance.