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Additional information

The currently available data do not allow for a definite conclusion on genetic toxicity and further tests may be required.

Ames test: S. typhimurium TA1535, TA1537, TA98 and TA100 and E. Coli WP2uvrA strains were exposed up to 5000 µg/plate of test material with or without metabolic activation. A pink colour, becoming darker with increasing concentrations, was noted from 150 µg/plate and above. In a range-

finding test, toxicity was observed at the dose level of 5000 µg/plate in the absence and presence of S9-mix in all tester strains. In addition, precipitation was observed at the dose level of 5000 µg/plate. Regarding mutagenicity, in the absence of S9, no increases in the number of revertant colonies were noticed whereas in the presence of S9 dose related increases in the number of revertant colonies were observed in all strains tested (range finding test: 4.7 - to 78 -fold; main test: 4.0- to 126 -fold).

The negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Based on the results of the Ames test the test material was considered to be mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.

Chromosome aberration test: Chinese Hamster Lung cells were exposed up to 4520 µg/mL test substance with or without metabolic activation.

The test material did not have any effects on pH and osmolatlity. Precipitation in the exposure medium was observed at dose levels of 282.5 µg/mL and above, also toxicity was observed. The test material did not induce any statistically significant increase in the frequency of cells with structural or numerical chromosome aberrations either in the presence or absence of a liver enzyme metabolising system or after various exposure times. In addition, the test material did not induce a statistically significant increase in the number of polyploid cells both in the absence and presence of S9-mix.

The number of cells with chromosome aberrations found in the solvent and positive control cultures were within the expected range.

Based on this the test material was considered to be non-clastogenic to CHL cells in vitro.

Mouse lymphoma assay:

The maximum dose level used was limited by the test material induced toxicity. Precipitation of the test material was observed during the course of the study at and above 160 µg/mL. The vehicle (solvent) controls had acceptable mutant frequency values that were within the normal range. Except for the vehicle control in the 24 hours treatment time without S9, which was slightly above the maximum historical control value. The study integrity was not adversely affected by the deviation.

The positive control materials induced marked increases in the mutant frequency indicating the satisfactory of the test and of the activity of the metabolic system.

The test material did not induce any toxicologically significant or dose-related increases in the mutant frequency at any of the exposure groups, which included dose levels where optimum or near optimum levels of toxicity were observed.


Short description of key information:
In vitro studies, i.e. an Ames, a chromosome aberration test and a mouse lymphoma test, are currently available. The tests were performed according to OECD guidelines and GLP. The substance is considered mutagenic in the Ames test, but non-clastogenic in mammalian cells and not mutagenic in the mouse lymphoma assay. Therefore, no conclusion on genetic toxicity can yet be drawn.

Endpoint Conclusion:

Justification for classification or non-classification

Based on the currently available data, i.e. in vitro data, conclusions for classification on genotoxicity according to the CLP Regulation (EC) 1272/2008 and Council Directive 67/548/EEC (DSD) cannot be drawn.

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