2-methylpent-2-enal

Endpoint summary

Additional information

Ames-Test:

The substance 2-Methylpenten-2-al-1 was tested for mutagenicity in the Salmonella typhimurium/ Escherichia coli reverse mutation assay both in the standard plate test and in the liquid suspension assay (= preincubation method) with and without the addition of a metabolizing system obtained from rat liver (S-9 mix) using the Salmonella strains TA 1535, TA 100, TA 1537, TA 98 and Escherichia coli WP2 uvrA according to EU Method B13/B14 and OECD Guideline 471. In the standard plate test, no increase in the number of revertants were found in all tested strains with and without S-9 mix. In the liquid suspension assay in the tests without S-9 mix, at the tested strain TA100, mutagenicity was observed from about 500 µg - 1000 µg/plate (factor 1.4 - 1.8) onward with a maximum increase in the number of his+ revertants by a factor of 3.4 - 3.7 at 2500 µg - 3000 µg/plate. In the strains TA1535, TA1537, TA 98 and E. coli WP2 uvrA, no increase in the number of his+ and trp+ revertants was observed. In the liquid suspension assay in the tests with S-9 mix, at the tested strain TA100, positive reaction from about 2000 µg - 2500 µg/plate (factor 1.4 - 1.8) onward with an increase in the number of mutant colonies by a factor of 1.6 - 1.8 at 2500 µg - 5000 µg/plate (1st liquid suspension assay) or of 3.1 at 5000 µg/plate (2nd liquid suspension assay). In the strains TA1535, TA1537, TA 98 and E. coli WP2 uvrA, no increase in the number of his+ and trp+ revertants was observed.

Thus, under the experimental conditions chosen here, it is concluded that 2-Methylpenten-2-al-1 is a mutagenic agent in a bacterial reverse mutation test in vitro (BASF, 1998).

In a disregarded non-guideline, non-GLP study, 2-Methyl-2 -penten-1 -al was not found mutagenic in the Ames-Test (Florin, 1980).

HPRT-Test:

The study was performed to investigate the potential of 2-Methylpent-2-enal to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster. The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed with and without liver microsomal activation and a treatment period of 4 hours. The second experiment was performed with a treatment time of 4 hours with and 24 hours without metabolic activation. The maximum concentration of 1150 μg/mL in the pre-experiment was equal to a molar concentration of about 10 mM. The dose range of the main experiments was limited by cytotoxic effects. The test item was dissolved in DMSO. No substantial and reproducible dose dependent increase of the mutation frequency was observed up to the maximum concentration with and without metabolic activation. Appropriate reference mutagens (EMS and DMBA), used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system. (BASF, 2012)

Short description of key information:
2-Methylpenten-2-al was tested for mutagenicity in a bacterial reverse mutation assay in a scientifically acceptable well documented study according to OECD guideline 471. Under the experimental conditions chosen here, it is concluded that 2-Methylpenten-2-al-1 is a mutagenic agent in a bacterial reverse mutation test in vitro. In a supporting non-guideline, non-GLP study, 2-Methyl-2 -penten-1 -al was not found mutagenic in the Ames-Test.
Due to the positive results of the bacterial reverse mutation assay, 2-Methylpenten-2-al was also tested for mutagenicity in an additional mutation assay using a mammalian cell line (OECD 476). Under the experimental conditions chosen, 2-Methylpenten-2-al-1 was non-mutagenic in mammalian cells.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the available data, classification and labelling of 2 -Methylpent-2-enal is not necessary according to EU Directive 67/548/EEC and EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.