Ecotoxicological Effects of Polyvinyl Chloride Microplastics on Limnodrilus hoffmeisteri Influenced by Key Environmental Parameters

ABSTRACT The toxicological effects of polyvinyl chloride microplastics (PVC MPs) on Limnodrilus hoffmeisteri have not been reported previously. Thus, in this study, the toxic effects of PVC MPs on L. hoffmeisteri and associated toxicological mechanisms were determined in indoor simulations during exposure for 21 days. According to the superoxide dismutase activity, the toxic effects of PVC MPs on L. hoffmeisteri were significantly mediated by dissolved oxygen, water temperature, ultraviolet light and the typical photocatalyst TiO 2 . Furthermore, under combined exposure to these four factors, PVC MPs led to changes in the protein content and respiratory index, and even caused DNA damage and tail breakage in L. hoffmeisteri . Moreover, HCl and OH· were identified and quantified as dominant compounds related to the toxic effects of PVC MPs on L. hoffmeisteri . These findings demonstrate that PVC MPs can significantly affect and hinder the growth of L. hoffmeisteri as emerging contaminants in aquatic ecosystems.