Registration Dossier

Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Non mutagenic in Ames test.

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

Genetic toxicity in vivo

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Based on available information, a weight of evidence approach has been followed for the assessment. Structural analogues have been tested for mutagenic potential in bacteria. A detailed description of the read across process is attached in section 13.

Genetic toxicity studies in bacteria (Ames test) were conducted following OECD guideline 471, using four Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100. Based on current version of this guideline, the use of a fifth strain is required. However, for both substances, no indications of mutagenicity were found in any tested strain, with or without metabolic activation, using standard plate test as well as preincubation test. Therefore, a mutagenic potential could be reasonably excluded.

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008) a mutation means a permanent change in the amount or structure of the genetic material in a cell. The term ‘mutation’ applies both to heritable genetic changes that may be manifested at the phenotypic level and to the underlying DNA modifications when known.

The more general terms ‘genotoxic’ and ‘genotoxicity’ apply to agents or processes which alter the structure, information content, or segregation of DNA, including those which cause DNA damage by interfering with normal replication processes, or which in a non- physiological manner (temporarily) alter its replication.

For the purpose of classification for germ cell mutagenicity, substances are allocated to one of two categories:

Category 1: substances known to induce heritable mutations or to be regarded as if they induce heritable mutations in the germ cells of humans.

Category 1A: based on positive evidence from human epidemiological studies.

Category 1B: based on:

- positive result(s) from in vivo heritable germ cell mutagenicity tests in mammals; or

- positive result(s) from in vivo somatic cell mutagenicity tests in mammals, in combination with some evidence that the substance has potential to cause mutations to germ cells.

- positive results from tests showing mutagenic effects in the germ cells of humans, without demonstration of transmission to progeny; for example, an increase in the frequency of aneuploidy in sperm cells of exposed people.

Category 2: substances which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans, based on positive evidence obtained from experiments in mammals and/or in some cases from in vitro experiments, obtained from:

- somatic cell mutagenicity tests in vivo, in mammals; or

- other in vivo somatic cell genotoxicity tests which are supported by positive results from in vitro mutagenicity assays

Based on negative results in two available studies, relying on a weight of evidence approach, a mutagenic potential to bacteria was excluded for Basic Blue 026 leuco.

Accordingly, it is not classified under the CLP Regulation (EC 1272/2008).