Low-density polyethylene microplastics partially alleviate the ecotoxicological effects induced by cadmium exposure on the earthworm Eisenia fetida

LDPE had no effect on the mortality, growth, and reproduction of earthworms. LDPE did not alter the mortality, growth, and reproduction of earthworm caused by Cd. LDPE alleviated histopathological damage to earthworms caused by Cd. LDPE alleviated DNA damage in earthworm coelomocytes caused by Cd. LDPE did not affect the accumulation of Cd in earthworms. Cadmium (Cd) can accumulate in the food chain, with serious impacts on human health and safety. Microplastics (MPs) such as low-density polyethylene (LDPE) should be considered not only as a single pollutant but also as a carrier of other pollutants. In this study, we investigated the joint effects of 30% LDPE and 313 mg kg −1 Cd on mortality, growth, reproduction, microstructure, DNA damage, oxidative stress, and mRNA levels in the earthworm Eisenia fetida . We found that 313 mg kg −1 Cd inhibited growth and reproduction and damaged the microstructures of the skin and intestine. Meanwhile, LDPE had no effect on the mortality, growth, or cocoon production of earthworms. Moreover, it did not increase the mortality, growth, or inhibition of cocoon production caused by Cd and instead alleviated the DNA damage in coelomocytes caused by Cd treatment. Finally, it did not alter the accumulation of Cd in the worms. These indicators can be used for toxicity safety assessment and soil ecological risk assessment of LDPE and Cd cooccurrence in soil.