On August 12, 2020, news provider Chemical Watch published a commentary article by Andrew Turley on the challenges of registering polymers under the European Chemicals Regulation REACH. Turley acknowledges the unprecedented scope of REACH, but he points out that large classes of substances have not been included since REACH entered into force in 2007, and polymers fall into this gap.

The scale of the challenge in combination with non-binding phrasing in the legal text were identified as main reasons for this delay. Under REACH, article 138(2) states that “the Commission may present legislative proposals as soon as a practicable and cost-efficient way of selecting polymers for registration on the basis of sound technical and valid scientific criteria can be established.” This should be addressed after the publication of “a report on [. . .] (a) the risks posed by polymers in comparison with other substances; (b) the need, if any, to register certain types of polymer, taking account of competitiveness and innovation on the one hand and the protection of human health and the environment on the other”.

The report on the risks posed by polymers was released in June 2020 and a summary by Clelia Oziel was published in Chemical Watch on July 9, 2020.

From this report Turley identified “some alarming numbers.” There are 200’000 different polymers available on the market and half of them were classified as polymers of low concern. For the remaining polymers, the authors of the report proposed a framework for prioritization, leaving 33’000 polymers that require registration. Based on sufficient similarities, the authors then identified 11’000 “unique polymers” and recommended their handling in individual registration dossiers.

In the second part of the commentary, Turley provides the chemical background of polymerization reactions, explaining that under certain conditions the possible reaction products “are proliferating exponentially” and that “the nature of polymerization [. . . ] is a kind of controlled chaos at the molecular level.” The products always differ in the size of the molecules, and reactions lack a precise control on a molecular level. Thus, polymerization reactions produce an extraordinary level of diversity that is “a headache for the regulatory community,” Turley states. Especially the size of the molecules strongly affects their bioavailability, i.e., the ability to pass biological barriers.

In conclusion, Turley discusses that the substance-focused approach under REACH is efficient for many chemicals, but not ideal for the regulation of polymers. An alternative could be that registrations focus more on the reactions rather than the substances, “because polymers are not just another class of chemicals. They are products of reactions that are fundamentally different to those producing other kinds of chemicals – and close attention to the nature of polymerisation may be needed to ensure that any changes to REACH are efficient”. A first step into this direction could be the formation of groups of co-registrants and data sharing between companies to make sure that they are dealing with the same substances.

Read more

Andrew Turley (August 12, 2020). “Comment: Why have polymers proved such a challenge for regulators?Chemical Watch

Clelia Oziel (July 9, 2020). “Framework for REACH polymer data requirements set out in EU study.Chemical Watch

Andrew Turley (August 12, 2020). “Industry: proposed criteria for REACH registration of polymers need refining.” Chemical Watch

Cleclia Oziel (September 17, 2020). “Adopt ‘common’ approach to EU polymer registration, ACC tells European Commission.” Chemical Watch


European Commission (June 2020). “Scientific and technical support for the development of criteria to identify and group polymers for Registration/Evaluation under REACH and their impact assessment.” (pdf)