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Administrative data

Key value for chemical safety assessment

Additional information

Ames test

In a reverse gene mutation assay in bacteria, strains TA 97, TA 98a, TA 100, TA 102, TA 1535 of Salmonella typhimurium were exposed to 400160 in sterile ethanol at concentrations of 5002 / 1501 / 500 / 150 / 50 µg/plate in the plate incorporation method and at concentrations of 5003 / 2502 / 1251 / 626 / 313 µg/plate in the pre-incubation method. Both test methods were conducted in the presence and absence of mammalian metabolic activation.

400160 was tested at limit concentration (5000 µg/plate) for cytotoxicity. No cytotoxicity could be observed. The positive controls induced the appropriate responses in the corresponding strains. There was no evidence of induced mutant colonies over background.

Under the test conditions 400160 is not mutagenic.

This study was performed according to test guidelines OECD guideline 471 and EU B.13/14 for bacterial reverse gene mutation data in a GLP certified testing facility.

Micronucleus test

The genotoxic potential of the test item, 400160 was evaluated in an in vitro micronucleus assay in human peripheral blood lymphocytes, both in the presence and in the absence of metabolic activation by rat S9 mix. The assay was performed according to OECD guideline No. 487 and under GLP compliance. In two independent experiments, cells were exposed to concentrations of the test item ranging from 4 to 500 µg/mL in ethanol for 4 h [with (exp.I + II) and without metabolic activation (exp. I)] or 18 h [without metabolic activation (exp. II)]. Cyclophosphamide monohydrate at concentrations of 15 and 7.5 µg/mL in 0.9% NaCl (for experiments with metabolic activation) and mitomycin C at concentrations of 0.15 and 0.3 µg/mL in aqua demin. (for experiments without metabolic activation) were used as positive controls. There were no signs of cytotoxicity during the study. The positive controls induced the appropriate response. Treatment of the cells with the test item did not induce significant increase in the number of micronucleated cells, as compared to vehicle controls after any incubation time. Thus, the results of this study indicate that the test item 400160 is not genotoxic to human peripheral blood lymphocytes under the experimental conditions reported.

Mouse lymphoma test

The study was performed to investigate the potential of 400160 to induce mutations at the mouse lymphoma thymidine kinase locus using the cell line L5178Y.

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 h. The second experiment was performed with a treatment period of 24 h in the absence of metabolic activation and 4 hours in the presence of metabolic activation.

The highest concentration (4200 µg/mL) applied in the pre-experiment was chosen with regard to the solubility of the test item in organic solvents and aqueous media. The concentration range of the main experiments was limited by precipitation of the test item.

No substantial and reproducible dose dependent increase in mutant colony numbers was observed in both main experiments. No relevant shift of the ratio of small versus large colonies was observed up to the maximal concentration of the test item.

In conclusion it can be stated that under the experimental conditions reported the test item 400160 did not induce mutations in the mouse lymphoma thymidine kinase locus assay using the cell line L5178Y in the absence and presence of metabolic activation.

 


Short description of key information:
AMES TEST
400160 was tested in an Ames test according to OECD guideline 471 an EU B.13/14 in the tester strains TA 97a, TA 98, TA 100, TA 102, TA 1535 of Salmonella typhimurium with and without metabolic activation. No mutagenicity was observed.

MICRONUCLEUS TEST
400160 was tested in an in vitro micronucleus assay according to OECD guideline 487 in human peripheral blood lymophocytes with and without metabolic activation. No genotoxicity was observed.

MOUSE LYMPHOMA
400160 was tested in an in vitro mammalian cell gene mutation test according to OECD guideline 476 and EU B.17 using the cell line L5178Y. No mutagenicity was observed.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Due to the negative results of three in vitro genotoxicity assays, it can be concluded that 400160 is not genotoxic. 400160 does not meet the current EU-CLP criteria for classification as a genotoxic substance. No risk phrase is required.