Earthworm (<i>Eisenia andrei</i>)-Mediated Degradation of Commercial Compostable Bags and Potential Toxic Effects

Abstract

The availability of compostable plastic bags has increased greatly in the past few years, as it is perceived that this type of bags will be degraded after disposal. However, there are some knowledge gaps regarding the potential effects on the soil ecosystems. We assessed the rate of degradation of samples of four different types of commercial compostable bags in vermicomposting systems with the earthworm species Eisenia andrei. We also evaluated the biological response of E. andrei (survival and reproduction) to microplastics (MPs) from fragments of the plastic bags (Lepidium sativum L.) exposed to micronized plastic (L. sativum seedling emergence was not significantly affected; however, earthworm reproduction was affected, suggesting that although compostable, some of the formulations may potentially be toxic to soil fauna.

Keywords

• degradable plastics
• additives
• ecotoxicity
• model organisms
• terrestrial ecosystems