Vermicomposting as a Sustainable Detoxification Strategy for Pesticide-Contaminated Agricultural Wastes: Mechanisms and Earthworm Physiological Responses

Abstract

Pesticide-contaminated agricultural residues represent an important waste-management concern because residues may persist in crop biomass after harvest and enter soil, water, or atmospheric pathways through unsuitable disposal practices. This review examines vermicomposting as a biological approach for reducing pesticide loads in agricultural wastes and discusses the mechanisms by which earthworms and associated microorganisms may contribute to detoxification. The manuscript synthesises literature on pesticide-contaminated crop residues, pesticide fate during vermicomposting, earthworm physiological responses, process-control factors, and safety evaluation of vermicompost outputs. Particular attention is given to enzymatic hydrolysis, oxidative transformation, microbial co-metabolism, sorption, humification, and bound-residue formation within the vermicomposting matrix. Earthworm responses, including acetylcholinesterase inhibition, oxidative stress, coelomocyte activity, heat-shock protein expression, reproduction, and survival, are considered potential indicators of pesticide stress and process performance. The review also discusses operational variables, including feedstock pre-treatment, carbon-to-nitrogen ratio, moisture, temperature, aeration, and worm species selection. Available evidence suggests that vermicomposting can contribute to the reduction of several pesticide classes in organic residues under controlled conditions, although degradation efficiency varies with pesticide chemistry, initial concentration, substrate composition, earthworm species, and processing duration. The review further highlights the need for standardised analytical methods, mixture-toxicity studies, field-scale validation, and clearer regulatory benchmarks for vermicompost derived from contaminated feedstocks. Overall, vermicomposting appears to be a promising component of sustainable agricultural waste management, but its application to pesticide-contaminated residues requires careful feedstock characterisation, process monitoring, and ecotoxicological verification before routine agronomic use.