New Insights into Biochemical, Genotoxic, and Analytical Aspects of Low-Level Imidacloprid Exposure in Liver and Kidney Tissue of Adult Male Wistar Rats

Besides its neurotoxic action and selective toxicity on insecticidal nicotinic acetylcholine receptors, recent studies have shown that imidacloprid may cause other adverse effects in mammals. In the present study, cholinesterase activity, oxidative stress response, genotoxicity in the liver and kidney, and imidacloprid levels in the urine, liver, and kidney of male Wistar rats orally administered with 0.06, 0.8, and 2.25 mg imidacloprid/kg bw/day for 28 days were evaluated. Imidacloprid urine mass concentrations in treated rats increased dose-dependently. Exposure to 0.8 mg imidacloprid/kg bw/per day significantly decreased cholinesterase activities in the liver and kidney. Reactive oxygen species levels decreased significantly in the liver at the same dose. Lipid peroxidation was significantly reduced in the liver at two higher doses. No significant changes in glutathione levels or the activities of superoxide dismutase and catalase were observed. A significant decrease in the activity of glutathione peroxidase was detected in the liver at the highest dose. DNA damage was low in both liver and kidney. Exposure to imidacloprid at studied experimental conditions did not cause a significant oxidative stress response and resulted in low genotoxic effects in the liver and kidney of rats, indicating that these organs are less susceptible to adverse imidacloprid effects at such low doses.