Titanium dioxide nanoparticles: Toxicity and genotoxicity in Drosophila melanogaster (SMART eye-spot test and comet assay in neuroblasts)

Titanium dioxide nanoparticles (TiO2NP) are used in the food, drug, and cosmetics industries and evaluation of their human and environmental toxicity is required. We have tested the toxicity of TiO2NP (anatase) with respect to developmental effects and DNA damage in Drosophila melanogaster strain Ok, using the eye-spot Somatic Mutation and Recombination Test (SMART) and the comet assay (neuroblasts). For the survival assay, TiO2NP were supplied to adult flies for 72 h and no adverse effects were seen. TiO2NP were supplied chronically for the prolificacy, SMART, and comet assays. TiO2NP increased fly prolificacy. With regard to genotoxicity, an increase was observed in the eye-spot SMART assay at 8 μg/mL dose, but not in the neuroblast comet assay for DNA damage.