Defining Quality Criteria for Nanoplastic Hazard Evaluation: The Case of Polystyrene Nanoplastics and Aquatic Invertebrate Daphnia spp.

Abstract

Polystyrene nanoparticles are the most investigated type of nanoplastics in environmental hazard studies. It remains unclear whether nanoplastic particles pose a hazard towards aquatic organisms. Thus, it was our aim to investigate whether the existing studies and data provided therein are reliable in terms of data completeness. We used the example of Daphnia spp. studies for the purpose of polystyrene nanoplastic (nanoPS) hazard evaluation. First, a set of quality criteria recently proposed for nanoplastic ecotoxicity studies was applied. These rather general criteria for all types of nanoplastics and different test organisms were then, in the second step, tailored and refined specifically for Daphnia spp. and nanoPS. Finally, a scoring system was established by setting mandatory (high importance) as well as desirable (medium importance) criteria and defining a threshold to pass the evaluation. Among the existing studies on nanoPS ecotoxicity for Daphnia spp. (n = 38), only 18% passed the evaluation for usability in hazard evaluation. The few studies that passed the evaluation did not allow for conclusions on the hazard potential of nanoPS because there was no consensus among the studies. The greatest challenge we identified is in data reporting, as only a few studies presented complete data for hazard evaluation.

Insights into Anthropogenic Micro- and Nanoplastic Accumulation in Drinking Water Sources and Their Potential Effects on Human Health

“…Most studies have been conducted on the exposure of marine organisms to commercial PS NPs purchased from authorized institutions or polyethylene terephthalate (PET) NPs. This is because PS NPs have been detected in the marine environment [80] and PET is the most widely used material for manufacturing bottles and packaging [81,82]. Few studies have been dedicated to investigating the effects of NPs released into drinking water sources on human health.…”

Progress in Research on the Bioavailability and Toxicity of Nanoplastics to Freshwater Plankton

“…Numerous research papers have demonstrated the uptake of NPLs and their aggregates by various zooplankton species through both waterborne and foodborne exposure [79][80][81][82][83]. Among these species, daphnids have been extensively studied [84], particularly Daphnia magna, which constituted 79% of the studied cases, followed by Daphnia pulex (18%), and Daphnia galeata (3%) [85]. Daphnia sp.…”

“…serve as filter feeders and act as primary consumers, forming a crucial link between primary producers and higher trophic levels in freshwater ecosystems [86]. Studies have examined both "apical endpoints"-including mortality/immobility, growth, feeding and egestion, swimming behavior, reproduction, embryonic development, body adsorption-and mechanistic endpoints such as oxidative stress, detoxification, immune-related processes, neurotoxicity, energy metabolism, heart rate, changes in gut epithelium, and processes related to moulting [85].…”