Benzaldehyde

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

With the completion of contemporary OECD TG 487 and TG 490 studies, the overall Weight of Evidence supports the classification of benzaldehyde as "not genotoxic". The whole of the literature points to benzaldehyde as not genotoxic, with only a small number of studies concluding "positive" results. In particular,

Citation	Test System	Conclusion

Several in vitro and in vivo genotoxicity tests with the test substance are available. The key studies come from the NTP report on the test substance (NTP, 1990). The test substance is negative in an in vitro mutagenecity study with Salmonella typhimurium with and without metabolic activation. In a chromosome aberration study the testsubstance did not induce effects both with and without metabolic activation. In a mouse lymphoma study a slightly positive result was reported both with and without S-9 mix.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

The test substance was not mutagenic in Salmonella gene mutation assays (Florin et al., 1980; Kasamaki et al., 1982; Haworth et al., 1983).

It exhibited genotoxic activity in the mouse lymphoma assay (McGregor et al., 1989) and in assays for sister chromatid exchanges in both Chinese hamster ovary (CHO) cells (Galloway etal., 1986). Induction of chromosomal aberrations by the test substance was also reported in Chinese hamster lung cells at a dose stated to be 50 nM (5.3 ng/ml) (Kasamaki et al., 1982); however, the National Toxicology Program (NTP), using concentrations of the test substance which were approximately 10,000 times higher, found no increase in aberrations in CHO cells (Galloway et al., 1986). This basic pattern of no mutagenic activity in bacterial systems but possible weak clastogenic effects in some mammalian cell assays is also reflected in test results from metabolites of the test substance, i.e., benzoic acid.

In in-vivo sex-linked recessive lethal mutation assays with Drosophila melanogaster the test substance was tested negative after oral and ip administration.

No adequate in vivo data are available that confirm the weakly positive results reported in in vitro tests.

Justification for selection of genetic toxicity endpoint
The study in mammalian cells was chosen over that in bacterial cells, as the higher level study.

Justification for classification or non-classification

The available data do not lead to classification for genotoxicity according to DSD and CLP.