Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

Three in vitro assays were performed to evaluate the genotoxicity of the test substance. At first, the material was tested for its mutagenic potential based on the ability to induce point mutations in selected loci of several bacterial strains, i.e.Salmonella typhimurium and Escherichia coli, in a reverse mutation assay (TA 1535, TA 100, TA 1537, TA 98 and E. coli WP2 uvrA). The test item was applied at concentrations of 33 μg - 5000 μg/plate (standard plate test) and 33 μg - 5000 μg/plate (pre-incubation test) in presence and absence of a metabolic activation system (S9 mix). Precipitation of the test substance was found depending on the test conditions from about 1 000 μg/plate onward. No bacteriotoxic effect was observed under all test conditions.

The substance was assessed for its potential to induce gene mutations at thehypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in Chinese hamster ovary (CHO) cells in vitro. Two independent experiments were carried out, both with and without the addition of liver S9 mix from phenobarbital- and beta-naphthoflavone induced rats (exogenous metabolic activation) at concentrations up to 50 ug/ml. The test substance was poorly soluble in culture medium. In this study, in the absence and the presence of metabolic activation no cytotoxicity was observed up to the highest required concentration. Thus, concentrations at the border of test substance solubility in culture medium were investigated for the induction of gene mutations. Based on the results of the present study, the test substance did not cause any relevant increase in the mutant frequencies either without S9 mix or after the addition of a metabolizing system in two experiments performed independently of each other. Thus, under the experimental conditions of this study, the test substance is not mutagenic in the HPRT locus assay under in vitro conditions in CHO cells in the absence and the presence of metabolic activation.

The substance was assessed for its potential to induce structural chromosome aberrations (clastogenic activity) and/or changes in the number of chromosomes (aneugenic activity) in V79 cells in vitro. Two independent experiments were carried out, both with and without the addition of liver S9 mix from induced rats (exogenous metabolic activation) at concentrations up to 100 ug/ml. A sample of 100 metaphases for each culture was analyzed for chromosomal aberrations, except for the positive control cultures where only 50 metaphases were scored due to clearly increased aberration rates. The test substance was poorly soluble in culture medium. In this study, no cytotoxicity indicated by distinctly reduced cell numbers or mitotic rates was observed up to the highest applied test substance concentrations which were at the border of test substance solubility in culture medium. On the basis of the results of the present study, the test substance did not cause any biologically relevant increase in the number of structurally aberrant metaphases incl. and excl. gaps at both sampling times either without S9 mix or after adding a metabolizing system. No relevant increase in the frequency of cells containing numerical chromosome aberrations was demonstrated either. Thus, under the experimental conditions described, the test item is considered not to have a chromosome-damaging (clastogenic) effect under in vitro conditions in V79 cells in the absence and the presence of metabolic activation.


Short description of key information:
An Ames tests, an HPRT assay and a chromosome aberration test in CHO cells and V79 cells, respectively, was performed according GLP and OECD guideline 471, 473 and 476to evaluate the mutagenic potential of the test substance. The test item did not induce mutations or chromosome aberrations in vitro. Therefore, the substance is not considered to be mutagenic under the conditions of these tests.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available studies are considered reliable and suitable for classification purposes under 67/548/EEC. As a result the substance is not considered to be classified for genotoxicity under Directive 67/548/EEC.

 

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

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for genotoxicity under Regulation (EC) No. 1272/2008.