Lack of Genotoxicity of Carbon Nanotubes in a Pilot Study

Abstract

Background: Different types of carbon nanotubes may represent toxic hazards due to their size distribution and massive surface area. They may adsorb other toxic agents that can consequently be transported into the body. The aim of the present study was to determine the possible genotoxicity of carbon nanotubes. Materials and Methods: In vivo bacterial mutagenicity and in vitro cytogenetic studies were performed on single-walled and multi-walled carbon nanotubes. Results: Oral exposure to nanotubes did not increase urinary mutagenicity in rats as studied using Ames test. No genotoxic effect was found in the in vitro micronucleus and sister chromatid exchange assays, either. Mitotic inhibition, a possible cytotoxic effect, however, was observed in the human lymphocyte cultures upon treatment with single-walled tubes. Conclusion: Due to the limited toxicity data on carbon nanotubes, these results may be particularly important for risk assessment purposes.