Resource and animal use implications of the proposed REACH information requirements for endocrine disruptor assessment.

Revised information requirements for endocrine disruptor (ED) assessment of chemicals under the European Union's Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Regulation have been proposed. Implementation will substantially increase demands for new data to inform ED assessment. This article evaluates the potential animal use and financial resource associated with two proposed ED policy options, and highlights areas where further clarification is warranted. This evaluation demonstrates that studies potentially conducted to meet the proposed requirements could use tens of millions of animals, and that the approach is unlikely to be feasible in practice. Given the challenges with implementing either policy option and the need to minimise the reliance on animal testing, further consideration and clarification is needed on several aspects prior to implementation of the requirements. This includes how testing will be prioritised in a proportionate approach; how to harness new approach methodologies to waive higher-tier animal testing; and need for provision of clear guidance particularly in applying weight-of-evidence approaches. There is now a clear opportunity for the European Commission to lead the way in developing a robust and transparent ED assessment process for industrial chemicals which fully implements replacement, refinement, and reduction of the use of animals (the 3Rs).