UTTAR PRADESH JOURNAL OF ZOOLOGY

Engineered copper oxide nanoparticles (CuO NPs) are increasingly released into terrestrial environments through industrial discharge, agrochemicals, biosolid amendments, and waste streams, raising concerns regarding their potential impacts on soil biota. Earthworms constitute ecologically significant detritivores that are widely utilized as bioindicators in terrestrial ecotoxicology. This study assessed the chronic toxicity of CuO nanoparticles to Perionyx sansibaricus, a tropical epigeic earthworm of ecological and vermicomposting importance, under a standardized 28-day artificial soil exposure. Test concentrations included 0, 200, 400, 600, 800, and 1000 mg CuO kg⁻¹ dry soil. The present work deals with the impact of different concentrations of copper NPs on the survivability of earthworm Perionyx sansibaricus. Survivability rates decreased significantly with increasing concentration of CuO NPs. The average survivability was 87.25%,62%,52%,38.34% and 19.25% for doses 200, 400, 600, 800 and 1000 mg kg^-1 respectively. A significant, dose-dependent and duration dependent toxicity of cuo nanoparticles on Perionyx sansibaricus was observed. Given the widespread agricultural use of CuO-based products, the study emphasizes the need for stricter environmental monitoring, responsible usage, and safe disposal practices to mitigate unintended harm to non-target soil organisms such as earthworms. The assessment of ecological danger and the management of CuO NPs utilized in diverse fields will benefit greatly from this study.