Naphthalene-1,5-diol

Endpoint summary

Additional information

Based on the SCCS (2010) evaluation

1,5-Naphthalenediol was investigated for the induction of gene mutations in Salmonella typhimurium (Ames test) using TA98, TA100, TA102, TA1535 and TA1537 and concentrations up to 5000 µg/plate in the presence and in the absence of a metabolic activation system. Both in experiment I and II no biological relevant increase in revertant colonies was seen in any of thefore tester strains following treatment with 1,5-naphthalenediol neither in the absence nor in the presenceof S9-mix.

Thus, under the experimental conditions used 1,5 -naphthalenediol was not genotoxic (mutagenic) in the gene mutation tests in

bacteria.

1,5-Naphthalenediol was assayed for gene mutations at the tk locus of mouse lymphoma cells both in the absence and presence of S9-mix metabolic activation according to OECD TG 476 and GLP. The concentration used ranged between 0.125 and 69 µg/plate.

Both in experiment I and II, independent of the presence or absence of S9 -mix, a biological relevant, reproducible increase in the number of mutant colonies was not observed. In conclusion, under the experimental conditions used, 1,5-naphthalenediol was considered not mutagenic in the mouse lymphoma assay at the tk-locus.

According to OECD TG 473 and GLP 1,5 -Naphthalenediol has been investigated in the absence and presence of metabolic activation for the induction of chromosomal aberrations in V79 cells in concentrations up to10 µg/ml. Test concentrations were based on the results of a pre-test on cell number and cell morphology, and viablity. Under the experimental conditions used, the increase in cells with structural chromosomal aberrations indicates a clastogenic activity of 1,5-naphthalenediol in V79 cells in vitro.

According to OECD TG 474 1,5 -Naphthalenediol has been investigated for the induction of micronuclei in bone marrow cells of mice. Test concentrations were based on the acute toxicity in a pre-test, measured at various intervals around 1 to 48 h after treatment. In the main experiment mice were exposed to single i.p. doses of 0, 12.5, 25 and 50 mg/kg bw. Clinical signs like reduction in spontaneous activity, abdominal position and ruffled fur indicating systemic toxicity were observed at all doses in most treated animals up to 24 h after start of the treatment. Biological relevant increases in the number of micronucleated PCEs compared to the concurrent vehicle controls were not found following treatment with 1,5-naphthalenediol at any time point or dose level tested. therefore, under the experimental conditions used, 1,5-naphthalenediol did not induce an increase in bone marrow cells with micronuclei in treated mice and, consequently, is 1,5- naphthalenediol not genotoxic (clastogenic and/or aneugenic) in bone marrow cells of mice.

In conclusion, 1,5-Naphthalenediol did not reveal genetic effects, neither in bacteria(Ames test) nor in the Mouse Lymphoma assay. 1,5-Naphthalenediol induced chromosome aberrations in Chinese Hamster V79 cells in vitro but did not cause an increase of micronuclei in bone marrow cells of treated mice.

Overall, 1,5-Naphthalenediol is evaluated as non-mutagenic and no classification/labeling is required

Justification for selection of genetic toxicity endpoint
Ames test (SCCS 2010) and LLNA (SCCS 2010) yielded negative results
Chromosome aberration test in V79 cells yielded a positive result, but MNT in vivo was negative

Short description of key information:
1,5-Naphthalenediol did not reveal genetic effects, neither in bacteria(Ames test) nor in the Mouse Lymphoma assay. 1,5-Naphthalenediol induced chromosome aberrations in Chinese Hamster V79 cells in vitro but did not cause an increase of micronuclei in bone marrow cells of treated mice.
Overall, 1,5-Naphthalenediol is evaluated as non-mutagenic.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Overall, based on the available data 1,5-Naphthalenediol is evaluated as non-mutagenic and no classification/labeling is required