Titanium dioxide nanoparticles tested for genotoxicity with the comet and micronucleus assays in vitro, ex vivo and in vivo

Publication date: Available online 2 May 2019Source: Mutation Research/Genetic Toxicology and Environmental MutagenesisAuthor(s): Alena Kazimirova, Magdalena Barancokova, Marta Staruchova, Martina Drlickova, Volkovova Katarina, Dusinska MariaAbstractThe genotoxicity of TiO2 nanoparticles (NPs) was assessed with the cytokinesis-block micronucleus (CBMN) assay in TK6 lymphoblastoid cells, lymphocytes from human volunteers, and bone marrow erythrocytes from rats exposed in vivo; and with the comet assay (detecting both strand breaks and oxidised purines) in human and rat peripheral blood mononuclear cells (PBMCs). NPs were dispersed using three different methods giving different size distribution and stability.On average, TiO2 NPs caused no increase in micronuclei in TK6 cells, rat bone marrow erythrocytes or human lymphocytes (though lymphocytes from 3 out of 13 human subjects showed significant increases).PBMCs from rats treated in vivo with a single dose of NPs dispersed by a method with low agglomeration showed an increase in strand breaks after 1 day.TiO2 NPs dispersed in a stable, non-agglomerated state induced DNA strand breaks at 75 µg/cm2 after 4 h exposure of human PBMCs and at 15 µg/cm2 and 75 µg/cm2 after 24 h exposure, but no increase in DNA oxidation was seen. Overall, NPs in an agglomerated state did not cause DNA damage. However, at the individual level, significant increases in strand breaks were seen in PBMCs from most of the volunteers. Cells from...
Source: Mutation Research Genetic Toxicology and Environmental Mutagenesis - Category: Genetics & Stem Cells Source Type: research