The impact on classifications for carcinogenicity, mutagenicity, reproductive and specific target organ toxicity after repeated exposure in the first ten years of the REACH regulation

The present study primarily aims at informing regulators and policy makers in Europe and examines the evolution of self-classifications and study availability for the endpoints of carcinogenicity, mutagenicity, reproductive toxicity (CMR) and specific target organ toxicity after repeated exposure (STOT RE) for the first ten years of the REACH legislation. Our knowledge on chemical safety keeps increasing due to the registration obligations under REACH, in combination with proactive actions by registrants and regulatory actions by Authorities, which jointly lead to new testing and critical reassessment of existing studies. The improvements become evident by the constant increase in the number of substances that are self-classified by the registrants for human health endpoints. Moreover, there is a slow but steady increase in the number of substances for which there is at least one experimental study available for the human health endpoints in scope of this analysis. However, the increase is slow given the generally limited data availability at the beginning of REACH. Manual examination of about 350 classified substances reveals that the impact of newly generated data and regulatory action by Authorities is greater for reproductive toxicity than for carcinogenicity or mutagenicity, reflecting the strengthening of the information requirements for reproductive toxicity with the introduction of REACH. The results of the study should inform regulators and policy makers at EU and national level in the discussion on potential changes to information requirements or testing strategies under REACH.