In the present study, green synthesized zinc sulfide nanoparticles (ZnS NPs) from the leaves of the medicinal plant, Abrus precatorius, were characterized and tested for toxicity using Eudrilus eugeniae. The formation of ZnS NPs through green synthesis was confirmed by using UV-Vis spectroscopy, FE-SEM, FT-IR, and XRD analyses. The clitellate earthworms were used to assess the effect of ZnS NPs by exposing to ZnS NPs 300 mg ZnS NPs per kg of OECD soil. On 0, 7, and 14 days of exposures, the coelomic fluid of the earthworms were separated and analyzed for total protein and protein profile, activities of enzyme markers such as superoxide dismutase (SOD), catalase (CAT), and protease. The results on the analysis of coelomic fluid of E. eugeniae after exposure to ZnS NPs showed a significant increase in protein content from the initial levels of 1.51 to 2.32 mg/mL with a protein profile of 25–40 kDa size. The activity of SOD was significantly (P < 0.05) declined from initial levels whereas CAT and protease showed a significant (P < 0.05) increase on 7th day of exposure then declined. The results indicate that the ZnS NPs in OECD soil significantly interfere with the protein and enzyme markers, SOD, CAT, and protease in earthworm coelomic fluid. [Figure not available: see fulltext.]. © 2020 Elsevier B.V., All rights reserved.