Tetrasodium 4,4'-bis[[4-[bis(2-hydroxyethyl)amino]-6-(4-sulphonatoanilino)-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate]

Endpoint summary

Additional information

Mutagenicity in bacterial reverse mutation assays (Ames test) was investigated in four tests.

The key study conducted in the Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA1538 was performed according to the OECD guideline 471, except for fact that the OECD recommended combination of strains was not respected, because none of the E. coli WP2 uvrA, or E. coli WP2 uvrA (pKM101), or S. typhimurium TA102 was tested (CCR- Cytotest Cell Research GmbH & Co. KG, 1987). Nevertheless, a second key study was here reported, in which the substance was tested for detecting its potential gene mutagenic activity using the Escherichia Coli strain WP2 uvrA (Guenard J., 1982). The test item did not cause relevant increase of the revertant colony numbers in both studies.

The same results were recorded also in further two AMES supporting studies (Bayer AG, 1979 and Bayer AG, 1979), in which no genotoxic and no cytotoxicity were observed during the experiment.

Thus, negative results were obtained in all tests with and without metabolic activation.

Mammalian mutagenicity test according to OECD 476 (HPRT) was performed on 3a-DSA, the analogous dihydroxyethyl hexasulphonated sodium salt; the substance has the same functional groups and it is a representative of the group 3 (further details are given in the Category Justification Report, Section 13 of the technical dossier). The in Vitro Mammalian Cell Gene Mutation Test was performed with V79 hamster fibroblast. The test substance was tested at the concentrations of 0.15; 0.5; 1.5 and 5 mg/ml. Each concentration was tested in two replicates. Experiments were performed without as well as with metabolic activation using the supernatant of rat liver and a mixture of cofactors. No evidence of the mutagenicity of test substance was recorded, thus the test substance resulted non-mutagenic for V79 cells without as well as with metabolic activation (Täublová E., 2014).

The chromosome aberration potential was investigated on the substance under registration both in vivo and in vitro: no indication of a mutagenic effect were recorded in the in vitro test (CCR- Cytotest Cell Research GmbH & Co. KG, 1991) and in the in vivo dominant lethal assay (Bayer AG, 1995); furthermore the substance did not induce micronuclei as determined by the micronucleus test with bone marrow cells of the mouse (CCR - Cytotest Cell Research GmbH & Co KG, 1991).

Justification for classification or non-classification

According to CLP regulation (EC1272/2008), for the purpose of the classification for germ cell mutagenicity, substances are allocated in one of two categories in consideration of the fact that they are: - substances known to induce heritable mutations or to be regarded as if they induce heritable mutations in the germ cells of humans or substances known to induce heritable mutations in the germ cells of humans or - substances which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans.

All different tests related to genetic toxicity are negative

In conclusion, the available experimental data are adequate for classification and labelling and the substance is not classified for genetic toxicity according to the CLP Regulation (EC 1272/2008).