Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

Naphthalene did not induce micronuclei in bone marrow of mice given single oral doses (50, 250, or 500 mg/kg) or intraperitoneal doses (250 mg/kg) (Harper et al. 1984; Pharmacon 1985). Naphthalene did not cause unscheduled DNA synthesis in hepatocytes from rats given single doses as high as 1,600 mg/kg (RTC 1999). Naphthalene (in the presence of rat liver metabolic activation) induced chromosomal aberrations in Chinese hamster ovary cells (Cockerham et al 1992). Naphthalene did not induce sister chromatid exchanges (in the presence or absence of rat liver metabolic activation) in Chinese hamster ovary cells (Cockerham et al 1992) and in human peripheral lymphocytes in the presence of uninduced rat-liver microsomes (Tingle et al 1993, not shown).


Short description of key information:
Naphthalene has given reproducible negative results in bacterial mutation assays, and was negative in an in vitro UDS assay. It was however found to be clastogenic in CHO cells in the presence but not the absence of S9. Two in vitro studies using CHO cells and human peripheral lymphocytes were negative for induction of SCE. Naphthalene was found to be negative in two in vivo bone-marrow micronucleus tests and an in vivo rat liver UDS study. Overall, the balance of evidence indicates that naphthalene is not genotoxic (HSE 2003).

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Overall, the balance of evidence indicates that naphthalene is not genotoxic. No classification needed.