Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

Most of the available Ames test with chenodeoxycholic acid, reported negative results for mutagenicity, with and without metabolic activation. ACD/Tox Suite, Leadscope, CAESAR and Toxtree led to the conclusion that the five biliary acids are NOT MUTAGEN. Moreover, according to a read-across approac, results are supported by the experimental findings (Ames test, gene mutation assay at the TK locus in mouse lymphoma L5178Y cells, assay of sister chromatid exchanges in cultured human lymphocytes and micronucleus test in hamsters) cited in the Australian Public Assessment Report for Ursodeoxycholic acid (2010).


Justification for selection of genetic toxicity endpoint
Most of the mutagenicity study (Ames tests) resulted negative for mutagenicity. Mutagenicity was also estimated employing three powerful QSAR predictors (ACD/ToxSuite, Leadscope, CAESAR) and one decision rule system (Toxtree), in order to apply a consensus approach and improve the reliability of the predictions. Moreover, according to a read-across approach, experimental results cited in the Australian Public Assessment Report for Ursodeoxycholic acid (2010) support the lack of mutagenicity of the biliary acid.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

According to regulation 1272/2008/EC, chenodeoxycholic acid is not classified for the mutagenicity.