Ingestion and contact with polyethylene microplastics does not cause acute toxicity on marine zooplankton

Abstract Toxicity of polyethylene microplastics(PE-MP) of size ranges similar to their natural food to zooplanktonicorganisms representative of the main taxa present in marine plankton, including rotifers, copepods, bivalves, echinodermsand fish, was evaluated. Early life stages (ELS) were prioritized as testing models in order to maximize sensitivity. Treatments included particles spiked with benzophenone-3 (BP-3), a hydrophobic organic chemical used in cosmetics with direct input in coastal areas. Despite documented ingestion of both virgin and BP-3 spiked microplasticsno acute toxicitywas found at loads orders of magnitude above environmentally relevant concentrations on any of the invertebrate models. In fish tests some effects, including premature or reduced hatching, were observed after 12 d exposure at 10 mg L −1 of BP-3 spiked PE-MP. The results obtained do not support environmentally relevant risk of microplasticson marine zooplankton. Similar approaches testing more hydrophobic chemicals with higher acute toxicityare needed before these conclusions could be extended to other organic pollutants common in marine ecosystems. Therefore, the replacement of these polymers in consumer products must be carefully considered.