Yousef Mohammadian - Department of Occupational Health, Health Faculty, Urmia University of Medical Sciences
Seyed Jamal Shahtaheri - Department of Occupational Health, School of Public Health, Tehran University
Ali akbar Saboor Yaraghi - Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Hossein Kakooei

Introduction: Carbon Nanotubes )CNTs( are one of the nanomaterials which have a huge range of applications in different industries. Recently some studies have reported adverse effects of these materials on human and animal cells at in vitro studies. In the current study the cytotoxicity of Single Walled Carbon Nanotubes )SWCNTs(, Multi Walled Carbon Nanotubes )MWCNTs( and Chrysotile asbestos on human lung epithelial cells )A549( was studied.Method: The cytotoxicity assessment was carried out in culture medium containing 10% serum using MTT assay. Human lung cells )A549( were exposed to different concentrations )0.97 to1500 μg/ml( of SWCNT, MWCNT and Chrysotile in both 6 and 24 hr exposure periods in both dispersion culture mediums containing 5% serum and 0.5% DMSO. Dose-response curves were obtained to determine the values of Non Observable Adverse Effect Concentration )NOAEC( and Inhibitory concentration 50% )IC50( indexes.Results: It is revealed that the type of culture medium used to disperse nanoparticles affects the cytotoxicity results of CNTs. The values of toxicological indexes for MWCNT were lower than theSWCNT, indicating more cytoxicity of MWCNT than SWCNT. Chrysotile asbestos fibers were less cytotoxic than CNTs at lower concentrations.Conclusion: Similar to asbestos fibers, CNTs have remarkable toxicity on human lung cells. MWCNT showed remarkable cytotoxicity at lower concentrations and it is necessary to be set in the priority of exposure control measures in the occupational environments.

Carbon Nanotubes, Chrysotile, Cytotoxicity assessment, MTT assay