3,3'-[(2-chloro-5-methyl-p-phenylene)bis[imino(1-acetyl-2-oxoethylene)azo]]bis[4-chloro-N-(3-chloro-o-tolyl)benzamide]

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Ames: negative; S. typhimurium TA98, TA 100, TA 102, TA 1535, TA 1537, TA 1538, E. coli WP2 uvr A, OECD 471, GLP not specified, K1

Micronucleus test: negative, human lymphocytes, OECD 487, GLP, K1

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Ames test:

The test substance was tested for mutagenic effects in vitro in histidine-requiring strains of Salmonella typhimurium and in a tryptophan-requiring strain of Escherichia coli. The following strains were used: S. typhimurium TA 98, TA 100, TA 102, TA 1535, TA 1537, TA 1538 and E. coli WP2 uvrA. The test was performed with and without the addition of rat-liver post mitochondrial supernatant (S9 fraction) as an extrinsic metabolic activation system. The compound was suspended in DMSO and tested at five concentrations in the range of 312.5 to 5000.0 μg/plate in the presence and absence of a metabolic activation system. In order to confirm the results, the experiments were repeated with and without metabolic activation at five concentrations in the range of 61.7 to 5000.0 μg/plate. Each strain was additionally tested in the presence and in the absence of a metabolic activation system with a suitable, known mutagen as positive control.
The original experiment with and without metabolic activation and the confirmatory experiment without activation were performed as standard plate incorporation assay. The confirmatory experiments with metabolic activation were carried out as preincubation assay.
In both experiments, performed with and without metabolic activation, none of the tested concentrations of the test substance led to an increase in the incidence of either histidine- or tryptophan-prototrophic mutants by comparison with the negative control.

 

In vitro micronucleus test:

The test substance was tested for its potential to induce micronuclei in primary human lymphocytes in vitro (clastogenic or aneugenic activity) in this study according OECD 487 and in complince with GLP. One experiment was carried out, incubating the cells for 20 h (20 h harvest time) with the test substance at concentrations in the range of 1.0 to 256 µg/mL. A sample of at least 1000 cells for each culture was analyzed for micronuclei, i.e. 2000 cells for each test group. In this study, 0.05% w/v BSA-water was selected as vehicle. The characterization of the nanomaterial in cell culture medium showed, that the particles were successfully dispersed into a stable suspension with partial agglomeration, that did not change significantly during the treatment period. The vehicle controls gave frequencies of micronucleated cells within our historical negative control data range for primary human lymphocytes. The positive control substances, Mitomycin C (MMC), Colchicine (Col) and the nanomaterial positive control Tungsten Carbide-Cobalt (WC-Co), led to the expected increase in the number of cells containing micronuclei.

The test substance was formulated in the given vehicle according to the NANOGENOTOXProject (Grant Agreement No 2009 21 01); Version 1.2, dated 06 May 2018.

In this study, no cytotoxicity indicated by reduced proliferation index (CBPI) was observed up to the highest applied test substance concentration. On the basis of the results of the present study, the test substance did not cause any biologically relevant in the number of cells containing micronuclei.
Thus, under the experimental conditions described, test material is considered not to have a chromosome-damaging (clastogenic) effect nor to induce numerical chromosomal aberrations (aneugenic activity) under in vitro conditions in primary human lymphocytes.

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 available data on genetic toxicity, the test item is not classified according to Regulation (EC) No 1272/2008 (CLP), as amended for the tenth time in Regulation (EU) No 2017/776.