John Libbey Eurotext

Environnement, Risques & Santé


Comparison of classification systems of carcinogenic agents: reasons for divergences and proposed equivalents Volume 22, issue 1, January-February 2023


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As part of work to prioritise potentially carcinogenic agents, national health security agencies, governments and other organisations, as well as researchers, are implementing various prioritisation methods. The use of score calculations has been chosen in several studies already published, in order to prioritise carcinogenic agents.

The hazard scores of carcinogens are primarily based on the different existing classifications dedicated to the carcinogenicity of the agents. According to the expert appraisals of the various bodies or research teams, equivalences have been achieved between the various non-regulatory classifications and the European classification from the “Classification, Labelling, Packaging” (CLP) regulation, without always leading to the same results.

Establishing formal equivalences is not possible due to multiple factors involved from the start to the end of the carcinogenic agent assessment process. However, due to similarities between the classification systems, statistical or more detailed equivalences according to the categories may be retained.

The objective of this analysis is, on the one hand, to identify the common points and differences between the classification criteria as well as the other parameters that may lead to classification discrepancies and, on the other, to propose equivalences between the European CLP classification and other classification systems.