Novel insights into acute/chronic genotoxic impact of exposure to tungsten oxide nanoparticles on Drosophila melanogaster

Abstract

Tungsten oxide nanoparticles (WO3 NPs) have now been employed by various products including electronics, smart screens, gas-biosensors, water purifiers, disinfectants, and biomedical applications. Despite this wide-ranging adoption, little research has investigated their potential endpoint biomarkers in different in vivo models. We therefore propose the use of Drosophila melanogaster as a testing model in assessing genotoxic risks of exposure to WO3 NPs. Our study examined toxicity, phenotypic alterations, locomotor behavior (climbing assay), intracellular oxidative stress (ROS), DNA damage (Comet assay), and somatic recombination (wing spot assay) in Drosophila melanogaster after exposure to WO3 NPs (43.71 ± 1.59 nm) and microparticulated (MPs) of WO3. Drosophila larvae were exposed to the test materials via ingestion at doses ranging between 1 and 10 mM, and two greatest doses of NPs (5 and 10 mM) were found to cause mutagenic/recombinogenic effects, while the MPs caused no effects. Wing-spot assay detected genotoxic activity of NPs mostly through somatic recombination, and Comet assay showed DNA damage after exposure to NPs at certain doses (1, 2.5, 5, and 10 mM). Other observations included ROS generation in hemocytes, phenotypic alterations in the mouths and wings of adult flies, and impaired locomotor behavior. This is the first research to report genotoxic evidence on the impact of WO3 exposure in Drosophila larvae, highlighting the significance of this model organism in exploring the potential biological impact of nanoparticles and MPs of WO3. The results of our in vivo testing should make a vital contribution to the existing database on the genotoxicity of WO3 NPs.