Registration Dossier

Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

not mutagenic

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

GENETIC TOXICITY IN VITRO

The test item was examined for the ability to induce gene mutations in tester strains of Salmonella typhimurium (TA1535, TA1537, TA98, TA100) andEscherichia coli(WP2 uvrA), as measured by reversion of auxotrophic strains to prototrophy. The test item was used as a solution in sterile water for injection. Experiments were performed both in the absence and presence of metabolic activation, using liver S9 fraction from rats pre-treated with phenobarbital and 5,6-benzoflavone (standard metabolic activation) in Main Assay I, and liver S9 fraction from uninduced hamsters (reductive metabolic activation system with Prival modification), in Main Assay II.

The test item was assayed in the toxicity test at concentrations of 5000, 1580, 500, 158 and 50.0 µg/plate.

Neither toxicity, nor relevant increases in revertant numbers were observed with any tester strain, at any dose level, in the absence or presence of S9 metabolism. On the basis of toxicity test results, in Main Assay I, using the plate incorporation method, the test item was assayed at dose levels of 5000, 2500, 1250, 625, 313 (for all strains) and 156 µg/plate (only for TA1537).

At the end of the incubation period, no relevant toxicity of the test item was seen, with any tester strain, at any dose level, in the absence or presence of S9 metabolism. As no relevant increase in revertant numbers was observed at any concentration tested, Main Assay II was performed. Based on the chemical structure of the test item (azo-dyes), the experiment was performed using the pre-incubation method in the presence of a reductive metabolic system (hamster S9 supplemented with flavin mononucleotide cofactor). The test item was assayed at the following dose levels: 5000, 2500, 1250, 625 and 313 µg/plate. Slight toxicity was observed in the absence of S9 metabolic activation at the highest dose level with TA1537 and TA100 tester strains.

No precipitation of the test item was observed at the end of the incubation period, with any tester strain, at any concentration tested, in the absence or presence of S9 metabolism, in any experiment.

The test item did not induce two-fold increases in the number of revertant colonies in the plate incorporation or pre-incubation assay, at any dose level, in any tester strain, in the absence or presence of any metabolic activation system.

Based on results of these experiments, the test item does not induce reverse mutation inSalmonella typhimuriumorEscherichia coliin the absence or presence of S9 metabolism.

Justification for classification or non-classification

Mutagenicity refers to the induction of permanent transmissible changes in the amount or structure of the genetic material of cells or organisms. These changes may involve a single gene or gene segment, a block of genes or chromosomes.

According to the CLP Regulation (EC 1272/2008), 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 (Category 1) or

-substances, which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans (Category 2).

Based on results of in vitro gene mutation studies performed, it is concluded that the test item did not induce gene mutations in reverse mutation in Salmonella typhimurium or Escherichia coli in the absence or presence of S9 metabolism.

According to the REACH Regulation EC 1907/2006, Annex VII, Column 2, further mutagenicity studies are not necessary to be considered in case of a negative result. Thus, it is possible to conclude that the test substance is considered to be non-genotoxic.