Ecotoxicological effects of microplastics and cadmium on the earthworm Eisenia foetida

• Published in: Journal of hazardous materials Vol. 392; p. 122273
• Main Authors: Zhou, Yanfei, Liu, Xiaoning, Wang, Jun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-06-2020
• Subjects: Animals; Biological Availability; Cadmium - toxicity; Combined exposure; Drug Synergism; Ecotoxicology; Eisenia foetida; Heavy metals; Microplastics; Microplastics - toxicity; Oligochaeta - drug effects; Oligochaeta - growth & development; Oligochaeta - metabolism; Oxidative stress; Soil Pollutants - toxicity; Oxidative stress; Microplastics; Combined exposure; Eisenia foetida; Heavy metals
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2020.122273

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•Microplastics and the synergic contamination of microplastics and heavy metal can induce adverse effects on Eisenia foetida.•Combined exposure to microplastics and cadmium enhances the negative effects of cadmium.•MPs particles are retained within Eisenia foetida, and retained particle numbers increase with exposure duration.•The presence of microplastics increase cadmium accumulation in Eisenia foetida.
As microplastics (MPs) have become ubiquitous in both aquatic and terrestrial environments, there has been a growing concern about these new anthropogenic stressors. However, comparatively little is known about the negative effects of MPs, co-contamination of MPs and heavy metals on terrestrial organisms. The objective of this study was performed to understand the adverse effects of exposure to MPs and co-exposure to MPs and cadmium (Cd) on the earthworm Eisenia foetida (E. foetida). Results showed that exposure to MPs only or to a combination of MPs + Cd decreased growth rate and increased the mortality (>300 mg kg−1) after exposure for 42 d, with MPs + Cd (>3000 mg kg−1) posing higher negative influence on the growth of E. foetida. Exposure to MPs might induce oxidative damage in E. foetida, and the presence of Cd accelerates the adverse effects of MPs. Furthermore, the MPs particles can be retained within E. foetida, with values of 4.3–67.2 particles·g-1 earthworm, and can increase the accumulation of Cd in earthworm from 9.7%–161.3%. Collectively, the results of this study demonstrate that combined exposure to MPs and Cd poses higher negative effects on E. foetida, and that MPs have the potential to increase the bioaccessibility of heavy metal ions in the soil environment.