Combined hepatotoxicity of imidacloprid and microplastics in adult zebrafish: Endpoints at gene transcription

Microplastics (MPs) and pesticides are two kinds of ubiquitous pollutants that can pose a health risk to aquatic organisms. However, researches about the combined effects of MPs and pesticides are very limited. A simple combined exposure model was established in this study, adult zebrafish were exposed to 100 mu g/L imidacloprid (IMI), 20 mu g/L polystyrene microplastics (PS), and a combination of PS and IMI (PS + IMI) for 21 days. The results demonstrated that exposure to PS and IMI inhibited the growth of zebrafish and altered the levels of glycolipid metabolism and oxidative stress-related biochemical parameters. While gene expression analysis revealed that, compared with PS or IMI treatment group, combined exposure caused a greater change in gene expression levels involving the process of glycolipid metabolism (Gk, Hk1, Aco, PPar-alpha, Cpt1, Acc, Fas, PPar-gamma, Apo) and inflammatory response (IL-1 beta, IL-6, IL-8, TNF-alpha, IL-10). The results demonstrated that even combined exposure of low concentrations of PS and IMI could cause more severe hepatotoxicity in zebrafish, especially in terms of gene transcription. And more combined toxicity studies are essential for MPs and pesticides risk assessment.

Automated summary

The study found that even low concentrations of combined exposure to microplastics and pesticides could lead to more severe hepatotoxicity in zebrafish and produce more significant changes at the gene expression level. More combined toxicity studies are essential for a more accurate risk assessment of microplastics and pesticides.