Exposure informed testing under REACH

Abstract

The level of exposure of humans and organisms in the environment to chemical substances can directly influence the number of tests with experimental animals that are necessary to ensure the adequate safety assessment of those substances. The consequence of this approach is that some tests may be waived if it can be shown that humans or organisms in the environment are either not or only minimally exposed to these substances (Exposure-Based Waiving, EBW). In such cases, fewer experimental animals are needed. In contrast, extra testing can be necessary - and therefore extra experimental animals - when the exposure to such substances is high (Exposure-Based Triggering, EBT). Extensive knowledge of the level and type of exposure through modelling or monitoring is essential for both EBW and EBT. Such modelling/monitoring applies to all relevant life-cycle stages of a substance, from the production to the waste stage. Only if such knowledge is available can the exposure be assessed to be relevant or not. In this context, the term exposure encompasses the direct exposure of humans to substances at the workplace or via consumer products, the indirect exposure of humans to substances via the environment as well as the exposure of organisms in the environment. RIVM and the Netherlands Organisation for Applied Scientific Research (TNO) have investigated how EBW and EBT can be used as a determinant in applying testing strategies and how EBW can be used to reduce the number of experimental animals required for the tests. This report is a product of the European Union's Sixth Framework Project OSIRIS (Optimized Strategies for Risk Assessment of Industrial Chemicals through Integration of Non-Test and Test Information). The aim of OSIRIS is to develop testing strategies for application under REACH that will lead to a reduction in the number of animal tests. The new European Regulation for the Registration, Evaluation, Authorisation and restriction of CHemicals (REACH) requires industry to submit a registration dossier. REACH has established tonnage-dependent testing requirements for industry. Under specific conditions, such as where exposure can be shown to be absent or minimal, REACH allows waiving of the tests.