Effects of PET microplastics on the freshwater crustacean Daphnia similis Claus, 1976

Abstract: Aim In this study, we investigated the effects of secondary PET microplastics (< 53 µm) on Daphnia similis basic life-history parameters survival, age at first reproduction and total offspring number. We also analyzed D. enzymatic activity (superoxide dismutase, catalase glutathione-S-transferase) sub-effect concentrations. Methods performed acute chronic toxicity tests using six concentrations (0, 102, 103, 104, 105 106 part. mL-1). applied an exposure test to analyze superoxide glutathione-S-transferase activities Results mortality increased (LC50 = 1 x mL-1), decreased (EC50 mL-1) time was delayed by 5 days highest microplastic concentration after 21 exposure. Neither nor alterations in or were detected 48 h Microplastics adhered body appendages, causing altered swimming behavior. Conclusions Lack but occurrence serve as a warning for caution when concluding about non-toxicity short-term tests. had unexpected with important ecological implications. Our results contribute fill knowledge gaps pollution aquatic ecosystems, especially under long-term