Mandal_2026_Sci.Total.Environ_1014_181293

The present study is designed to investigate the toxic effects of acetamiprid (ACE) on the tubificid worm by determining the median lethal concentration (LC(50)) and its effects on Tubifex tubifex, selecting the sub-lethal doses. In an extended period of exposure, ROS generation is elevated, which perturbs the physiological process. Neutral red retention time (NRRT) and MTT assays show decreased lysosomal membrane stability and mitochondrial dysfunction. Additionally, exposure to acetamiprid causes a notable elevation of antioxidant defence enzymes, catalases (CAT), superoxide dismutase (SOD), protein oxidation level through protein carbonyl adduct formation, lipid peroxidation level (LPO), level of lactate dehydrogenase (LDH), indicating tissue damage, glutathione peroxidase (GPx), and glutathione-S-transferase (GST) level. On the other hand, a significant decline in total protein content (TP), glutathione (GSH), glutathione reductase (GR), and acetylcholine esterase (AChE) levels indicates a stressful condition due to chronic exposure. In addition, the electron microscopy image reveals the epidermal changes as well as autotomy or shedding of the caudal part to remove the pesticide load. In conjunction with the integrated multi-biomarker (IBR) responses, the graphical changing trend of the star plots indicated that the tubificid worms' antioxidant defence system biomarkers are sensitive enough for a short-term ACE biomonitoring program.