Accelerated ecotoxicity of photoreactive nanoparticles on Moina macrocopa

ABSTRACT

Zinc oxide nanoparticles (ZnO NPs) and titanium dioxide nanoparticles (TiO2 NPs) are well known as photoreactive nanoparticles (NPs). Various phototoxicities of ZnO NPs and TiO₂ NPs were reported on several organisms. It was still necessary to evaluate the toxicity of photoreactive ZnO NPs and TiO₂ NPs due to species-specific effects under various irradiation conditions. We compared the acute toxicity of Moina macrocopa under visible, ultraviolet (UV) A, and B irradiations, according to the Organization for Economic Cooperation and Development guidelines for the testing of chemicals (Test No. 202). The sensitivity of ZnO NPs for M. macrocopa was UVB>UVA>visible light irradiation. There were no significant lethal and immobile effects of TiO₂ NPs on juveniles under all irradiations and in the tested concentrations of TiO₂ NPs. Photoreactive NPs have a potential and accelerated toxicity on organisms in the ambient environments.