Myristica fragrans, ext.

Endpoint summary

Additional information

- An Ames test in accordance with OECD 471 was performed to determine the mutagenic potential of Nutmeg oil to cause gene mutations in bacteria. Nutmeg oil did not induce a significant dose-related increase in the number of revertant (His+) colonies in each of the four tester strains (TA1535, TA1537, TA98 and TA100) and in the number of revertant (Trp+) colonies in test strain WP2uvrA both in the absence and presence of S9-metabolic activation. These results were confirmed in an independently repeated experiment. Furthermore, the negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly. Based on the results of this study it is concluded that Nutmeg oil is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.

- A Chromosomal Aberration test in vitro using a Chinese hamster fibroblast cell line (CHL) was carried out on Nutmeg oil. The test was performed similar to OECD Guideline 473. The cells were exposed to nutmeg oil at three different doses for 24 and 48 hours without metabolic activation. The maximum dose of the Nutmeg oil sample was selected by a preliminary test in which the dose needed for 50% cell-growth inhibition was estimated using a cell densitometer, representing the highest non-cytotoxic dose: 0.063 mg/ml. 100 metaphases were examined. Nutmeg oil did not induce chromosomal aberrations in CHL cells in vitro at 3 different concentrations in the absence of metabolic activation.

- Two supporting studies are available in which tests were performed with and without metabolic activation. Additionally, 4 studies are available that were disregarded, as they were assigned a Klimish value 3 based on limited data available on methods and results. Equivocal results were observed in two of these studies, however, as the effects were observed at the lowest dose only, and no independent repeat was performed, no conclusion can be drawn based on these studies.

Based on the findings in the 2 key studies, it can be concluded that Nutmeg oil does not cause gene mutations.

Short description of key information:
In vitro gene mutation in bacteria: not genotoxic (OECD 471)
In vitro cytogenicity study: not genotoxic (equivalanet or similar to OECD 473)

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the available information for Nutmeg oil, the substance can be considered not mutagenic and should therefore not need to be classified for mutagenicity according to the criteria outlined in 1272/2008/EC (CLP/EU-GHS) and 67/548/EEC. However, based on the Safrole content in Nutmeg oil the substance still has to be classified as genotoxic.