Neurotoxicity Following Exposure to Micro and Nanoplastics

The pervasive presence and enduring existence of micro and nanoplastics in the environment render their exposure to humans and aquatic creatures unavoidable. Research indicates these tiny plastic particles can be taken in by aquatic beings and mammals. Once within the body, micro and nanoplastics have the capability to infiltrate the brain, although the level of penetration and the subsequent neurotoxic effects are not fully explored. Previous studies indicate that metal (oxide) nanoparticles can enter the brain and induce neurotoxic effects. Given the chemical resemblances between plastic particles and inert metal (oxide) nanoparticles, this review aims to summarize existing studies on the neurotoxic implications of nanoplastics across various species and in vitro settings. The current evidence, although incomplete, suggests that exposure to nanoplastics may lead to oxidative stress, potentially causing cell damage and raising the risk of developing neurological disorders. Moreover, such exposure could inhibit acetylcholinesterase activity and alter neurotransmitter levels, potentially contributing to observed behavioral changes. There is a notable lack of systematic comparison regarding the neurotoxic effects stemming from different particle types, shapes, and sizes at various concentrations and durations of exposure. Understanding these aspects is essential for further evaluating the neurotoxic danger and risk associated with nanoplastics.