Butyl propionate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

In a GLP bacterial reverse mutation study conducted according to OECD TG 471, it was concluded that n-butyl propionate did not induce reverse gene mutation in the selected bacterial tester strains in the presence and absence of S9 mircosomal fraction obtained from rat liver homogenate.

In a GLP in vitro chromosomal aberration assay conducted according to OECD TG 476 and EPA OPPTS 870.5375 utilizing rat lymphocytes, n-butyl propionate was considered to be negative.

In a third GLP study, conducted according to OECD TG 476 (In vitro Mammalian Cell Gene Mutation Test) with category member n-pentyl propionate, there was no evidence of genotoxicity at the highest, non-cytotoxic, concentrations in the presence or absence of metabolic activation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

The mutagenic activity of n-butyl propionate was investigated in agar layer cultures of selected bacterial tester strains of Salmonella typhimurium and Escherichia coli. Assays were performed both in the presence and in the absence of an S9 microsomal fraction obtained from a liver homogenate from rats pre-treated with Aroclor 1254. Under the conditions of the study, it was concluded that n-butyl propionate did not induce reverse gene mutation in the selected bacterial tester strains.

In vitro cytogenicity of n-butyl propionate was evaluated in an in vitro chromosomal aberration assay utilizing rat lymphocytes in the presence and absence of S9 activation. There were no significant increases in the frequencies of cells with aberrations either in the absence or presence of S9. Statistical analyses of the data did not identify significant differences between the negative control and any of the treated cultures. Cultures treated with the positive control chemicals had significantly higher incidences of aberrant cells in all assays. Based upon these results, n-butyl propionate was considered to be negative in the in vitro chromosomal aberration assay utilizing rat lymphocytes.

The genotoxic potential of category member n-pentyl propionate to induce gene mutation in mammalian cells was evaluated using Chinese hamster ovary (CHO) cells. There was no evidence of induction of gene mutations in any of the treated cultures either in the presence or absence of metabolic activation. In each of these experiments, the respective positive controls produced a statistically significant increase in the frequency of mutants, under identical conditions and the concurrent vehicle control cultures values were within laboratory historical controls. Under the conditions of this study, the catgory member n-pentyl propionate was non-mutagenic when evaluated in the presence or absence of an externally supplied metabolic activation (S9) system.

Justification for classification or non-classification

As negative results were noted in the Bacterial Reverse Mutation test (AMES) and rat lymphocyte chromosome aberration test with n-butyl propioate, and in the mammalian cell mutagenicity assay with category member n-pentyl propionate, and as per the Guidance to Regulation (EC) No. 1272/2008 on Classification, Labelling and Packaging of substances and mixtures, n-butyl propionate will not be classified for genotoxicity.