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. 2020 Jul 1;22(7):1444-1460.
doi: 10.1039/d0em00147c. Epub 2020 Jun 4.

Strategies for grouping per- and polyfluoroalkyl substances (PFAS) to protect human and environmental health

Ian T Cousins  1 , Jamie C DeWitt, Juliane Glüge, Gretta Goldenman, Dorte Herzke, Rainer Lohmann, Mark Miller, Carla A Ng, Martin Scheringer, Lena Vierke, Zhanyun Wang
Affiliations

Strategies for grouping per- and polyfluoroalkyl substances (PFAS) to protect human and environmental health

Ian T Cousins et al. Environ Sci Process Impacts. .

Abstract

Grouping strategies are needed for per- and polyfluoroalkyl substances (PFAS), in part, because it would be time and resource intensive to test and evaluate the more than 4700 PFAS on the global market on a chemical-by-chemical basis. In this paper we review various grouping strategies that could be used to inform actions on these chemicals and outline the motivations, advantages and disadvantages for each. Grouping strategies are subdivided into (1) those based on the intrinsic properties of the PFAS (e.g. persistence, bioaccumulation potential, toxicity, mobility, molecular size) and (2) those that inform risk assessment through estimation of cumulative exposure and/or effects. The most precautionary grouping approach of those reviewed within this article suggests phasing out PFAS based on their high persistence alone (the so-called "P-sufficient" approach). The least precautionary grouping approach reviewed advocates only grouping PFAS for risk assessment that have the same toxicological effects, modes and mechanisms of action, and elimination kinetics, which would need to be well documented across different PFAS. It is recognised that, given jurisdictional differences in chemical assessment philosophies and methodologies, no one strategy will be generally acceptable. The guiding question we apply to the reviewed grouping strategies is: grouping for what purpose? The motivation behind the grouping (e.g. determining use in products vs. setting guideline levels for contaminated environments) may lead to different grouping decisions. This assessment provides the necessary context for grouping strategies such that they can be adopted as they are, or built on further, to protect human and environmental health from potential PFAS-related effects.

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Conflict of interest statement

Conflicts of Interest

This paper does not necessarily reflect the opinions or the policies of the German Environment Agency. Ian Cousins has provided expert reports in three separate class actions related to PFAS in the Federal Court of Australia. Jamie DeWitt is serving as a plaintiff’s expert witness in several cases related to PFAS. No other authors declare any conflicts of interest.

Figures

Figure 1.
Figure 1.
Grouping approaches for PFAS.
Figure 2.
Figure 2.
Chemical structures of various potentially bioaccumulative PFAS (other than the already well-known long-chain PFAAs). Note that this figure only provides a few examples of potentially bioaccumulative PFAS from the wider universe of PFAS.
Figure 3:
Figure 3:
Schematics of increasing resolution in information detail of analytical methods used for PFAS analyses.
See this image and copyright information in PMC

References

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