NCHR’s Comments on Proposed Supplemental Guidance for CPSC Chronic Hazard Guidelines

October 23, 2023

We appreciate the opportunity to comment on CPSC’s proposed rule regarding: “Proposed Supplemental Guidance for CPSC Chronic Hazard Guidelines.” We have several questions and serious concerns.

The National Center for Health Research (NCHR) is a nonprofit think tank that conducts, analyzes, and scrutinizes research on a range of health issues, with a particular focus on which prevention strategies and treatments are most effective for which patients and consumers. We do not accept funding from companies that make products that are the subject of our work, so we have no conflicts of interest.

We agree that a revised guidance may be needed to help industry to meet their labeling obligations under the FHSA and the Labeling of Hazardous Art Materials Act (LHAMA), but we found the proposed guidance to be vague and confusing. 

The CPSC claims that Chronic Hazard Risk Assessment methodology has advanced so much from 1992 that a new policy is warranted, but also that the 2008 update is sufficient because this methodology has not changed significantly since then. That makes no sense. Moreover, the proposed guidance was apparently drafted in 2008 and yet CPSC does not explain why the draft was not posted for comments for 15 years and is now being posted for the first time.

We question whether it is appropriate to recommend using linear modeling of benchmark dose assessment for all carcinogens and non-carcinogens, since, for example, it is well-established that many endocrine disrupting chemicals do not fit this model. The proposed guidance does not include that information, or discuss any concerns about the use of linear modeling for any other class of chemicals. Therefore, encouraging the use of this model may lead to the underestimation and overestimation of risk associated with certain harmful substances.

Perhaps exceptions are intended to be acknowledged by stating that companies may undergo their own risk assessment, but this is so vague that it could be an enormous loophole.  For example, on page 4 the proposed guidance states that “ risk assessors may deviate from the default assumptions described in the guidelines, provided that their methods and assumptions are documented, scientifically defensible, and supported by appropriate data as in indicated in section VI.A.2 of the preamble of the guidelines (57 FR 46633).” On page 31 it states that “guidelines are not binding” and are “amenable to professional judgements.” The instances under which it would be appropriate to deviate from these guidelines are not specified. It is unclear what entities would be responsible for making sure the assumptions documented are “scientifically defensible, and supported by appropriate data.” We urge the CPSC to specify what expert bodies would be appropriate for undergoing such assessments and under what conditions it would be acceptable to deviate from the assessment methodology outlined in the guidance.

When determining the thresholds under which a substance would be considered safe, it is essential that the limitations set for safe exposure are based on sound science. Industry and the CPSC have a responsibility to the consumer to ensure that chronic hazards are identified under strict scrutiny so there is no question regarding the validity of the limits set for exposure to certain substances. It is paramount that CPSC makes this clear in its updated guidance and explains when it would be appropriate to deviate from the methodology outlined in this guidance, as well as specifying alternatives methods of determining risk.