2-isobutyl-4-vinyl-1,3-dioxolane

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

In a bacterial reverse mutation assay (Ames) according to OECD Guideline 471, the test item did not show mutagenic properties (2017).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

In a bacterial reverse mutation assay (Ames) according to OECD Guideline 471, the potential of the test item to induce gene mutations was investigated in the Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100, and the Escherichia coli strain WP2 uvrA. The assay was performed in three independent experiments with and without liver microsomal activation (S9 mix). Each concentration, including the controls, was tested in triplicate. The test item was tested at the following concentrations:

Pre-Experiment/Experiment I:       3, 10, 33, 100, 333, 1000, 2500, and 5000 µg/plate

Experiment II and IIa:

Strain TA 100 (Exp. II):                 10; 33; 100; 333; 1000; 2500; and 5000 µg/plate

The remaining strains (Exp. II): 33, 100, 333, 1000, 2500, and 5000 µg/plate     

Strain TA 98 (Exp. IIa):                 3;10; 33; 100; 333; 1000; and 2500 µg/plate

The test item precipitated in the overlay agar in the test tubes in experiment I at 5000 µg/plate with metabolic activation and in experiment II at 5000 µg/plate with and without metabolic activation. Precipitation of the test item in the overlay agar on the incubated agar plates was observed in experiment I from 2500 to 5000 µg/plate with metabolic activation and in experiment II at 5000 µg/plate with and without metabolic activation. In experiment IIa no precipitation was observed when tested up a top dose of 2500 µg/plate. The undissolved particles had no influence on the data recording of this study. The plates incubated with the test item showed normal background growth up to 5000 µg/plate with and without S9 mix in all strains used. Toxic effects, evident as a reduction in the number of revertants (below the indication factor of 0.5), were observed in experiment I in strains TA 1535, TA 1537 and TA 100, in experiment II in all strains except strain TA 1535, and in experiment IIa in strain TA 98. No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with the test item at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Appropriate reference mutagens were used as positive controls and showed a distinct increase of induced revertant colonies.

In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used. Therefore, the test item is considered to be non-mutagenic.

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008.

Based on this data, the substance is not considered to be classified for genetic toxicity under Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EU) No 2017/776.