Lethal and sub-lethal effects of nanosized titanium dioxide particles on Hydropsyche exocellata Dufour, 1841

Nanosized titanium dioxide particles (nTiO) are one of the most widely used nanoscale engineered materials. Evidence of the presence of nTiO in freshwater systems has been reported by recent ecotoxicological studies, which indicated the potential toxic effects of nTiO to aquatic organisms. This study aimed at exploring lethal and sub-lethal endpoints of aqueous exposure of the aquatic insect Hydropsyche exocellata Dufour, 1841 (Trichoptera, Hydropsychidae) to nTiO at different concentrations. Abdominal contractions significantly increased with nTiO exposure. Levels of lipid peroxidation (LPO) increased with nTiO dose, whereas the opposite was recorded for the antioxidant enzyme catalase activity (CAT). Moreover, the highest exposure (50.0 mg/L) resulted in the highest mortality (56% of mortality two weeks after pulse exposure to nTiO). Overall, our results show that nTiO has potential toxic effects on H. exocellata at concentrations of 50.0 mg/L.