The ecotoxicology of microplastics and nano-plastics research on Daphnia_Current status and future directions

Abstract

In recent years, the pollution of plastics particles to the environment has become increasingly serious, especially the pollution of the water environment, which also makes micro- and nanoplastics become a hot topic of research. Pelagic filter-feeders, which link primary producers to higher trophic levels, are often used as animal models in water environment studies. Studies on the exposure of micro- and nanoplastics to Daphnia have been increasing year by year. This review conducted systematic statistics on 139 relevant articles, and found that the toxicity of micro- and nanoplastics to Daphnia is closely related to its type, shape, particle size and concentration, and is also related to whether Daphnia has sufficient food. However, the differences of experimental parameters in each study make it difficult to compare them with each other. In addition, the transgenerational toxicity, surface charge modification and additive leaching mechanisms of micro- and nanoplastics still need to be explored in depth. This review summarizes the limitations of current studies and suggests that future focus on environmentally relevant parameters, multifactorial dynamic exposure modeling and novel detection technologies are needed to improve the aquatic ecological risk assessment system.