Absence of mutagenic and recombinagenic activity of multi-walled carbon nanotubes in the Drosophila wing-spot test and Allium cepa test

• The NT has high purity: 98.95 percent of the weight corresponds to carbon.
• NT does not cause significant genotoxic effects in the Allium cepa test.
• NT is not toxic and did not induce DNA damage in somatic cells of D. melanogaster.

In order to assess the safety of the carbon nanotubes to human health and the environment, we investigated the potential toxicity and ability of multi-walled carbon nanotubes (NT), to induce DNA damage by employing the Allium cepa genotoxicity/mutagenicity test and the Somatic Mutation and Recombination Test (SMART) in the fruitfly, Drosophila melanogaster. The results demonstrated that NT did not significantly induce genotoxic or mutagenic effects in the Allium cepa test. All concentrations evaluated in the SMART assay showed survival rates higher than 90 percent, indicating the absence of chronic toxicity for NT. Furthermore, the various treatments showed no significant increase in the NT mutation and recombination frequencies in mwh/flr3 genotype compared to respective negative controls, demonstrating the absence of DNA damage caused by NT.