Evaluation of the genotoxic and mutagenic effect in human lymphocytes exposed to modified carbon nanotubes.

Objective: evaluate the genotoxic and mutagenic effect in human lymphocytes exposed to pristine and N-doped carbon nanotubes. Methods: Methods: human lymphocytes were exposed to pristine and N-doped carbon nanotubes (NTC) (0.08, 0.09, 0.1mg/mL). Sister chromatid exchange (SCE) and chromosomal alterations (CA) tests were evaluated. Results: chromatid breaks and chromosomal breaks (double strand breaks) were identified in lymphocytes exposed to 0.1 and 0.08 mg/mL of the pristine CNT. N-doped CNT, induced dicentric chromosomes and chromosomal rings. There was significant difference in the percentage of SCE of cells treated with doped NTC versus negative control and pristine NTC (p<0.0001). Conclusion: the highest concentration of pristine CNTs induced the most chromatid and chromosomal damage. Although the percentage was less than 10%, such degree of damage is considered harmful to cells. Lymphocytes treated with Ndoped CNT presented lower percentages of CA and high percentage of SCE, which shows a greater repair of genetic material with these compounds. [ABSTRACT FROM AUTHOR]