Tetrasodium 3-[[4-[[4,6-bis-[(3-sulfonatoprop-1-yl)thio]-1,3,5-triazin-2-yl]amino]-2-methyl-5-methoxy-phenyl]azonaphthalene-1,5-disulfonate

Endpoint summary

Additional information

In Vitro Data

Bacterial Reverse Mutation

Two studies are available that investigate the potential for the test material in induce mutagenic activity in bacterial reverse mutation assays.

In the first study by Molinier (1995) Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 were exposed to the test material in distilled water at dose levels of 30, 100, 300, 1000 and 3000 µg/plate. In two independent tests, the five doses of the test material (three plates/dose level) were tested on each strain, with and without S9 mix using the preincubation method (30 minutes at 30 °C). After 48 to 72 hours of incubation at 37 °C, revertants were scored with an automatic counter. Under the conditions of the test, the test material did not induce mutagenic activity. The study was conducted under GLP conditions and in accordance with the standardised guidelines OECD 417 and EU Method B.14.

In the second study by de Jouffrey (1996) Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and Escherichia coli strain WP2 uvrA were exposed to the test material at concentrations of 312.5, 625, 1250, 2500 and 5000 µg/plate (three plates/dose) in distilled water. Two independent tests were run both with and without metabolic activation (S9 mix) using the plate incorporation method, with the exception of the second test with S9 mix where the preincubation method was used. After incubation for 48 to 72 hours, revertants were scored with an automatic counter. Under the conditions of the test, the test material did not induce mutagenic activity. The study was conducted under GLP conditions and in accordance with the standardised guidelines OECD 417 and EU Method B.14.

 

Mammalian Chromosome Aberration

The potential genotoxicity of the test material was determined in an in vitro mammalian chromosome aberration test using cultured human lymphocytes by de Jouffrey (1996). The study was conducted under GLP conditions and in accordance with the standardised guidelines OECD 473, EU Method B.10 and USA/EPA/TSCA Federal Register, Vol. 50, No. 188, Subpart F.

The test material was investigated in two independent experiments, both with and without a metabolic activation system (S9 mix). The test material was administered in distilled water and both solvent and positive controls were carried out.

In the first experiment, lymphocytes were exposed to the test material for 3 hours at dose levels of 5000, 3000, 1000, 300, 100 and 30 µg/mL, with and without S9 mix. Exposure was followed by a 20 hour harvest time.

In the second experiment, two sets of exposure/harvest conditions were performed. With S9 mix, lymphocytes were exposed for 3 hours at dose levels of 5000, 3000 and 1000 µg/mL and then harvested at both 20 and 44 hours. Without S9 mix, lymphocytes were continuously exposed at dose levels of 5000, 3000, 1000 and 300 µg/mL for both 20 and 44 hours until harvest at either 20 or 44 hours, respectively.

Metaphase analysis was conducted at selected dose levels and the following structural aberrations were recorded: gaps, chromatid and chromosome breaks and exchanges and others (multiple aberrations and pulverisations). Polyploidy and endoreduplication numerical aberrations were also recorded for each metaphase. Cell cytotoxicity was determined as the mitotic index.

Slight to moderate cytotoxicity was observed. There was no statistically significant increase in chromosome aberrations observed in any of the treated cultures.

Under the conditions of the test, the test material did not induce chromosome aberrations in cultured human lymphocytes both with and without S9 mix for both experiments and all harvest times.

All studies were performed under GLP conditions and in accordance with standardised guidelines. The reports were conclusive and reported with a sufficient level of detail to assess the quality of the data. In accordance with the principles for assessing data quality defined by Klimisch et al. (1997), the studies were all assigned a reliability score of 1.

Justification for selection of genetic toxicity endpoint
A single study could not be selected as key since multiple studies have been presented to address different types of genetic toxicity.

Short description of key information:
IN VITRO DATA
Bacterial Reverse Mutation Assay: Negative, OECD 471, EU Method B14, Molinier 1995
Bacterial Reverse Mutation Assay: Negative, OECD 471, EU Method B14, de Jouffrey 1996
Mammalian Chromosome Aberration Assay: Negative, OECD 473, EU Method B10, USA/EPA/TSCA Federal Register, Vol. 50, No. 188, Subpart F, de Jouffrey 1996

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the submitted in vitro data, testing does not indicate any evidence of genetic toxicity of the test material. In accordance with criteria for classification as defined in Annex I, Regulation (EC) No. 1272/2008, the test material does not require classification for genetic toxicity.