Assessment of pesticide toxicity on earthworms using multiple biomarkers: a review

Two million tonnes of pesticides are currently used globally to improve crop production, yet these pesticides induce adverse effects on soil quality and biodiversity. Moreover, less than 1% of pesticides reach the target pests, while the rest contaminate the surrounding environment. In particular, earthworms are exposed to pesticides and are thus an ideal biological model for ecotoxicological research. Here, we review acute and sub-lethal effects of pesticides on earthworms. We found that pesticides alter growth, reproduction, behaviour, essential enzymes, and DNA of earthworms, even at low pesticide concentrations. These sub-lethal biomarkers allow to evaluate the overall response of an earthworm to pesticides, and to identify the risk for other non-target organisms.