Ecotoxicity of Single-Use Plastics to Earthworms

Abstract

The excessive use of plastics in recent years, especially so-called single-use plastics, has led to an incipient increase in the presence of this material in the soil. As soil is the essential production factor in agriculture, this study aims to test the toxicity to earthworms of different concentrations of plastics using the same substrate for each sample. Earthworms are the main bioindicator of soil quality and are of particular ecological value because their disappearance or loss in population would have disastrous consequences for the environment. This study examines the growth, mortality and reproductive cycle of individual earthworms. The species to be studied is Eisenia fetida and during the test, individuals are immersed in five different concentrations: 1 mg/kg; 10 mg/kg; 100 mg/kg; 1000 mg/kg; and 2000 mg/kg. Bioplastic OK industrial compost (that meet the requirements established to comply with compostability according to EN 13432) was used. Whether the plastic in any of those concentrations is harmful to the worm population was then be checked. The test shows the mixture of PLA and PBAT (biodegradable plastic) studied has no significant effect on the population of Eisenia fetida. None of the variables studied yields significant data on this plastic and the effect it causes on the population of earthworms, Eisenia fetida.