title: Genotoxicity of colloidal fullerene C₆₀.
abstract: Previous genotoxicity tests of aqueous fullerene C₆₀) suspension (aqu-C₆₀) yielded both positive and negative results. In the present study, aqu-C₆₀ elicited positive responses in two bacterial genotoxicity tests, the Bacillus subtilis Rec-assay and the umu test at concentrations as low as 0.048 mg/L and 0.43 mg/L, respectively. In mammalian cell experiments, aqu-C₆₀ showed a significant growth inhibitory effect on human hepatocarcinoma HepG2 cells at 0.46 mg/L. The level of the oxidative DNA lesion 8-oxo-7,8-dihydro-2'-deoxyguanosine, measured by liquid chromatography tandem mass spectrometry, was slightly but not significantly increased in HepG2 cells treated with 0.46 mg/L for 24 h, whereas the level of the lipid peroxidation-related DNA lesion α-methyl-γ-hydroxy-1,N²)-propano-2'-deoxyguanosine was not changed. Under the same conditions, we did not detect any bulky DNA adducts, as measured by ³²P-postlabeling/polyacrylamide gel electrophoresis analysis. Our data suggest that aqu-C₆₀ has DNA-damaging potential and that the DNA damage is not due to covalent DNA adduct formation by C₆₀ itself.
authors.affiliation: Research Center for Environmental Quality Management, Kyoto University, Otsu, Shiga 5200811, Japan. matsuda@z05.mbox.media.kyoto-u.ac.jp
authors.forename: Shun
authors.initials: S
authors.lastname: Matsuda
authors.forename: Saburo
authors.initials: S
authors.lastname: Matsui
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Tomonari
authors.initials: T
authors.lastname: Matsuda
mesh_terms: D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D003102:Colloids / Q000633:toxicity; D004247:DNA / Q000378:metabolism; D004249:DNA Damage / Q000187:drug effects*; D037741:Fullerenes / Q000633:toxicity*; D056945:Hep G2 Cells; D006801:Humans; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D010084:Oxidation-Reduction
chemical_list: D003102:Colloids; D037741:Fullerenes; D009153:Mutagens; D004247:DNA; C069837:fullerene C60