Chronic and transgenerational effects of polyethylene microplastics at environmentally relevant concentrations in earthworms

Microplastics are introduced into the agroecosystem through the application of wastewater and biosolids, plastic mulch films, greenhouse materials, and soil conditioners. Microplastics accumulation can alter the soil ecosystem and cause adverse effects on soil organisms. Therefore, this study for the first time evaluated the acute and chronic effects of pure and commercial polyethylene microplastics (PEMP) at environmentally relevant concentrations (0.01–0.5%) on earthworms (Eisenia fetida). Exposure to PEMP in the soil at 0.5 % concentration caused 70% reduction in earthworm reproduction for both parents (F0) and first filial (F1) generations compared to PEMP unamended control soil. Moreover, significant DNA damage was observed in F0 generations after 28 days. Also, this study demonstrated the release of phthalates used as additives in plastic and their accumulation by earthworms exposed to PEMP-amended soils. Thus the findings of this study have great implications for the risk assessment of PEMPs in the environment.