Evaluation of the Effects of Nitrilotriacetic Acid as a Chelating Agent on the Biochemical Toxicity of Lead in Oreochromis niloticus.

In the present research, the effects of sublethal lead (Pb) concentrations on total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) levels, enzyme activities (aspartate transaminase, AST; alanine transaminase, ALT; lactate dehydrogenase, LDH), ion levels (magnesium, Mg; sodium, Na; potassium, K; chlorine, Cl; calcium, Ca), and some metabolite levels (cholesterol, triglyceride, HDL, LDL, albumin, total protein) in the blood serum of Oreochromis niloticus and the protective function of nitrilotriacetic acid (NTA) due to its chelating characteristic were investigated. O. niloticus, which has an important position in the food chain and is often preferred in toxicological studies, was exposed to 0.1 ppm Pb, 0.1 ppm Pb + 0.3 ppm NTA, 1 ppm Pb, and 1 ppm Pb + 3 ppm NTA concentrations for 7 and 21 days. At the end of the duration, serum TAS and TOS levels were measured spectrophotometrically with Rel Assay Diagnostics; other enzyme activities, ion levels, and metabolite parameters were done by an autoanalyzer using commercial kits. Depending on the exposure periods and concentrations, the changes in the parameters were determined. It is determined that, under the influence of high ambient concentration of lead, TOS, OSI, AST, ALT, LDH, LDL, triglyceride, and Mg levels increased, while TAS, albumin, and K levels decreased after 21 days. These increases/decreases in all serum biochemical parameters were generally higher in fish treated with Pb alone compared to fish treated with a mixture of Pb + NTA. This study shows that these changes in serum parameters could be used as an indicator to assess on metal toxicity.