Filling gaps in science exposes gaps in chemical regulation

The regulation of chemicals should protect public health and the environment from undue risk of harm, should promote the development and use of safer alternatives to more hazardous chemicals, and should provide the public with sufficient information to understand how well chemical risks are being managed. How well are these goals being achieved? The regulatory system in the United States has been derided as dysfunctional (1), even with major amendments enacted in 2016 (2) that some supposed would bring the U.S. program closer to the European Union's REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) Regulation. To build on the literature that documents the shortcomings of chemical regulation (1, 2), we take as a convenient example the compounds described in new research by Washington et al. on page 1103 (3). Washington et al. report the unexpected presence in environmental samples of chloroperfluoropolyether carboxylate compounds (ClPFPECAs), apparently used as a substitute for other perfluoroalkyl substances (PFASs) that had raised environmental concerns (3). Attempting to trace these compounds through the regulatory regime raises more questions than answers, revealing the structural limits of existing regulation. These limits apply not only to this particular case but to myriad chemicals. How much confidence do regulatory systems give the public that substitute chemicals are safer than the substances they replace? Not nearly as much as one would like.