2,2,5-trimethyl-5-pentylcyclopentan-1-one

Endpoint summary

Additional information

Table 7.6/1: Summary of genotoxicity tests

Test n°	Substance tested	Test / Guideline Reliability	Focus	Strains tested	Test concentration	Statement
1   WIL Research Europe BV, 2014	Registered substance	Ames Test (OECD 471) K, rel. 1	Gene mutation	TA 1535, TA 1537, TA 98, TA 100 E.coli WP2 uvrA	Up to cytotoxic concentration	-S9 : non mutagenic +S9 : non mutagenic
2   WIL Research Europe BV, 2014	Read-across 2-Pentyl cyclopentan-1-one	L5178YTK+/-/MLA test (OECD 476) K, rel. 2	Gene mutation	L5178Y tk+/-(3.7.2C) mouse lymphoma cells	Up to cytotoxic concentration	-S9 : non mutagenic +S9 : non mutagenic
3   Bohnenberger, 2008	Read-across 2-pentylcyclopentan-1-ol	HL/CAT (OECD 473) K, rel.2	Chromosomal aberration	Human lymphocyte	Up to cytotoxic concentration	-S9 : non clastogenic +S9 : non clastogenic

Gene mutation Assays (Tests n° 1 -2):

- A Bacterial Reverse mutation Assay (Ames test) was performed according to OECD test guideline No 471 with the substance (See Table 1). No significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains, with any dose, either in the presence or absence of metabolic activation. The substance does not induce gene mutations in bacteria under the test condition whereas all positive control chemicals (with and without metabolic activation) induced significant increase of colonies. The substance is therefore considered as non-mutagenic according to the Ames test.

- Inability to produce gene mutation was confirmed in mammal cells using an in vitro gene mutation assay in L5178Y tk+/-(3.7.2C) mouse lymphoma cells (L5178Y TK+/- /MLA test) (Test n°2). None of the dose levels up to the cytotoxicity limit with the supporting substance (see IUCLID section 13 for read-across justification), either in the presence or absence of metabolic activation, induced significant mutant frequency increases in the initial or repeat experiments whereas both positive control chemicals (with and without metabolic activation) induced significant mutant frequency increases. Therefore, the supporting and the registered substance are considered as negative for inducing gene mutations at the TK locus in L5178Y mouse lymphoma cells under activation and non-activation conditions used in this assay. This result confirms the results of the Ames test and extends the non-mutagenic effect of the registered substance to mammalian cells.

 

Chromosomal aberration (Test n°3)

The clastogenic potential of the test material was determined with a supporting substance (see IUCLID section 13 for read-across justification) using an in vitro chromosome aberration test in Human lymphocytes, which measures the potential of a substance to increase the incidence of structural chromosome aberrations in cultured Human lymphocytes.

None of the dose levels up to the cytotoxicity limit with the supporting substance, either with or without metabolic activation, induced significant increases in the frequency of cells with aberrations in either of two experiments. The supporting substance does not induce structural aberrations in the chromosomes of Human lymphocytes under activation and non-activation conditions, whereas both positive control chemicals (with and without metabolic activation) induced significant increases in the frequency of aberrant cells. Therefore, both the registered substance and the supporting substance are considered as negative for inducing chromosomal mutations in Human lymphocytes in vitro under activation and non-activation conditions used in this assay.

Justification for selection of genetic toxicity endpoint
No study was selected, since all in vitro and in vivo studies performed on the substance itself or on supporting substances were negative and of high quality.

Short description of key information:
- Ames Test (OECD 471, GLP, K, rel. 1): non mutagenic up to cytotoxic concentration in S. typhimurium TA 1535, TA 1537, TA 98, TA 100 & E.coli WP2uvrA.
- L5178Y/MLA Mammalian Cell Gene Mutation Assay (OECD 476, GLP, Read-across, K, rel. 2): non mutagenic.
- Human lymphocytes chromosome aberration test (OECD 473, GLP, Read-across, K, rel. 2): non clastogenic.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Harmonized classification:

The test material has no harmonized classification for human health according to the Regulation (EC) No. 1272/2008.

Self-classification:

Based on the available data, no additional classification is proposed regarding germ cell mutagenicity according to the Annex VI of the Regulation (EC) No. 1272/2008 (CLP).