Potential impacts of titanium dioxide nanoparticles on the biochemical and behavioural status of the amphipods <i>Talitrus saltator</i> (Amphipoda, Talitridae)

Abstract

Titanium dioxide nanoparticles (TiO2 NPs) are among the most universally engineered nanomaterials and widely used nanomaterials in the world. In order to predict the environmental impact and interaction between these NPs and coastal organisms, the amphipod Talitrus saltator was exposed to TiO2 NPs C1 = 151.5 µg.L−1 and TiO2 NPs C2 = 303 µg.L−1. Catalase activity increased significantly and reaches a maximum of about 0.8 ± 0.02 µMol/min/mg proteins after exposure to TiO2 NPs C2 showing possible oxidative mechanisms. In addition, acetylcholinesterase activity reduced significantly (p < 0.05) after exposure to the highest TiO2 NPs concentration, indicating neurotransmission disturbance treated with 303 µg.L−1 of TiO2 NPs. Locomotor behaviour for untreated and treated specimens with TiO2 NPs was studied under constant darkness (DD). Results revealed the existence of ultradian and circadian components. In addition, locomotor activity patterns were generally bimodal for untreated specimens and became multimodal for treated ones. We noted also a slippage of the activity peak from the middle of the subjective night for the control until the subjective day after TiO2 NPs exposure. Furthermore, the most important stability was observed for control individuals who were more active than treated ones. Overall, this laboratory study provides preliminary toxicity data for Talitrus saltator exposed to TiO2 NPs.