Cyclohexanamine, 4,4'-methylenebis[N-(1-methylpropyl)-

Endpoint summary

Additional information

Genotoxicity in vitro (Section 7.6.1)

Clearlink 1000´s potential mutagenic activity in vitrohas been evaluated in two studies with bacterial cells and in two studies with mammalian cells. In the salmonella microsome assays no induction of gene mutations were observed. There were no indications of gene mutations in mammalian cells. Chromosome aberrations were independent of the metabolic activation system in mammalian cells.

Gene mutation in bacterial cells

Clearlink 1000 suspension in distilled water was tested in the bacteria back mutation assay, comparable to Ames test (by Hifumi et al. 2002), with and without metabolic activation for its ability to induce mutations in the strains S. typhimurium TA1535, TA 1537, TA 98, TA 100 and E. coli WP2 uvr A in six doses up to 5000 µg/plate. Test protocol was comparable to OECD Guideline 471. All the tested strains were negative with and without metabolic activation. Conclusion: the test result was determined negative.

In a Amest Test (by Lawlor et al. 1993) XPA-143 -93/Unilink 4200H (in ethanol) was tested for its ability to induce mutation in strains S. typhimurium TA1535, TA 1537, TA 1538, TA 98 and TA 100. All the strains were tested with and without metabolic activation with six doses from 100 up to 5000 µg/plate. Test protocol was comparable to OECD Guideline 471 with acceptable restrictions (no strain to detect cross linking properties was included). The test substance did not cause a positive increase in the number of histidine revertants per plate of any of the tester strains either in the presence or absence of metabolic activation. Conclusion: the test result was determined negative.

Gene mutation in mammalian cells

The potential gene mutagenic activity in mammalian cells has been evaluated with L5178Y cells in a study (by Verspeek-Rip et al. 2011), which included independent repeat. The study procedure was based on the following guidelines: OECD Guideline 476, Council Regulation (EC) No 440/2008 Guideline B.17 and the recommendations of the "International Workshop on Genotoxicity Tests Workgroup". After exposure to 3 and 24 hours, Clearlink 1000 did not induce gene mutations either with or without metabolic activation in doses up to 400 µg/ml.Conclusion: the test result was determined negative.

Chromosomal aberrations

In a chromosomal aberration study using mammals cells (Shozo et al. 2002) CHL/TU cells were exposed to Clearlink 1000 with and without metabolic activation. Clear dose dependent increase in structural and numerical chromosomal abnormalities was observed both with and without metabolic activation. Conclusion: the test result was determined positive.

Because of the positive result in the chromosomal aberration test,in vivomicronucleus test was conducted.

 

Genotoxicity in vivo (Section 7.6.2)

A micronucleus test was performed in compliance with GLP and according to OECD Guideline 474 Male and female NMRI BR mice (5 animals/sex/dose) were dosed via intraperitoneal injection with vehicle or with 100, 50 and 25 mg/kg bw of test substance (trade name Clearlink 1000). Bone marrow was sampled 24 (all dose levels) or 48 (highest dose only) hours after dosing. No decrease in the ratio of polychromatic to normochromatic erythrocytes compared to the concurrent vehicle control group was detected. Thus, under the experimental conditions of this test, the test substance does not have any clastogenic or aneugenic effect. Conclusion: the test result was determined negative.

Based on the results of these studies there is no evidence of genotoxicity in experimental animals.

 

Short description of key information:
Based on the available experimental animal data of the test substance (trade name Clearlink 1000) it is concluded that no genotoxicity is expected.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Classification regarding genetic toxicity is not required according to EU Directive 67/548/EEC and EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.