Impairment of DNA in a Freshwater Gastropod (Lymnea luteola L.) After Exposure to Titanium Dioxide Nanoparticles

• Published in: Archives of environmental contamination and toxicology 2015-04, Vol.68 (3), p.543-552
• Main Authors: Ali, Daoud, Ali, Huma, Alarifi, Saud, Kumar, Sudhir, Serajuddin, M., Mashih, Agha P., Ahmed, Mukhtar, Khan, Mujeeb, Adil, Syed Farooq, Shaik, M. R., Ansari, Anees A.
• Format: Article
• Language: English
• Subjects: Analysis; Animals; Aquatic ecosystems; Assaying; Bioassays; Biomarkers; Deoxyribonucleic acid; DNA; DNA Damage; Earth and Environmental Science; Ecosystems; Ecotoxicology; Electrophoresis; Environment; Environmental Chemistry; Environmental Health; Exposure; Fresh Water; Freshwater ecology; Freshwaters; Gastropoda; Glutathione - metabolism; Laboratories; Light scattering; Lymnaea - physiology; Lymnea; Microscopy, Electron, Transmission; Mollusks; Monitoring/Environmental Analysis; Nanoparticles; Nanoparticles - toxicity; Oxidative stress; Pollutants; Pollution; Snails; Soil Science & Conservation; Stress concentration; Studies; Titanium; Titanium - toxicity; Titanium dioxide; Toxicity; Transmission electron microscopy; Water Pollutants, Chemical - toxicity; Water pollution; Zoology
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-015-0132-0

The apoptotic and genotoxic potential of titanium dioxide nanoparticles (TiO 2 NPs) were evaluated in hemocyte cells of freshwater snail Lymnea luteola L. Before evaluation of the toxic potential, mean size of the TiO 2 NPs was determined using a transmission electron microscopy and dynamic light scattering. In this study, L. luteola were exposed to different concentrations of TiO 2 NPs (28, 56, and 84 μg/ml) over 96 h. Induction of oxidative stress in hemolymph was observed by a decrease in reduced glutathione and glutathione- S -transferase levels at different concentration of TiO 2 NPs and, in contrast, an increase in malondialdehyde and reactive oxygen species levels. Catalase activity was decreased at lower concentrations but increased at greater concentration of TiO 2 NPs. The extent of DNA fragmentation occurring in L. luteola due to ecotoxic impact TiO 2 NPs was further substantiated by alkaline single-cell gel electrophoresis assay and expressed in terms of % tail DNA and olive tail moment. The alkaline single-cell gel electrophoresis assay for L. luteola clearly shown relatively greater DNA damage at the highest concentration of TiO 2 NPs.The results indicate that the interaction of TiO 2 NPs with snail influences toxicity, which is mediated by oxidative stress according dose and in a time-dependent manner. The results of this study showed the importance of a multibiomarker approach for assessing the injurious effects of TiO 2 NPs to freshwater snail L. luteola , which may be vulnerable due to the continuous discharge of TiO 2 NPs into the aquatic ecosystems. The measurement of DNA integrity in L. luteola thus provides an early warning signal of contamination of the aquatic ecosystem by TiO 2 NPs.