Responses of Earthworms to Acetamiprid

Abstract

To increase agricultural output, millions of tonnes of neonicotinoids are reportedly used worldwide, but these agrochemicals have negative impacts on soil quality and biodiversity. 98% of pesticides applied reach non-target organisms in the water and soil including the earthworms. Earthworm provides significant contributions to soil fertility and serves as a bioindicator for pesticide-induced soil pollution in an ecotoxicological investigation. In this study, earthworms (Aporrectodea longa) were subjected to commercial-grade Acetaminprid at various doses for 14 days and the LC50 was found to be 2.52 mg/kg. Morphological alterations and behavioral changes such as weight loss, avoidance, and growth rate were observed to be concentration-dependent. Catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPx), C-reactive protein (CRP), and Total Oxidative Capacity (TAC) activities were also measured. Significant alterations in these stress markers were detected in pesticide-exposed earthworms at increasing pesticide concentrations. Our findings showed that the exposed earthworm's growth rate decreased, its digging activity slowed down, it died, and it lost a significant amount of weight. These findings varied significantly depending on the pesticide concentration. This study indicates that Earthworms are particularly susceptible to acetamiprid, which cause immobility and rigidity, as well as a reduction of biomass and growth by disturbing numerous physiological activities, resulting in a loss of the earthworm population.