Exposure to Acute Concentration of Malathion Induced Behavioral, Hematological, and Biochemical Toxicities in the Brain of Labeo rohita

A surge has been observed in the use of pesticides to boost agricultural yield in order to feed the continuously increasing human population. Different types and classes of broad-spectrum insecticides are in use, and the number is constantly increasing with the introduction of new ones. Keeping in view the broad-spectrum effects of organophosphate pesticides including Malathion (MLN), their use is continuously increasing without appraising their toxic impacts on non-target organisms. The continuous rise in the use of MLN has led to its presence, persistence, and transport to water bodies globally, subsequently affecting commercially valuable aquatic organisms. The current study was conducted to assess MLN-induced hematological and biochemical toxicities in the brain of a commercially valuable indigenous major carp, rohu, Labeo rohita. The fish was exposed to an acute concentration of commercial-grade MLN. The LC50 of MLN (5 µg/L) led to behavioral inconsistencies and subtle impacts on the hematology (an increase in white blood cells and a reduction in red blood cells, hemoglobin, packed cell volume level, and mean corpuscular hemoglobin concentration) and biochemistry (an increase in reactive oxygen species, lipid peroxidation, activities of antioxidant enzymes (catalase, peroxidase, superoxide dismutase, glutathione, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase) but a reduction in total protein content and activity of Na+/K+ ATPases) in the brain tissues. MLN also inhibited the activity of Acetylcholinesterase, while it led to an increase in Acetylcholine. Significant changes were observed in the serum biochemical profile; for example, glucose, cholesterol, potassium, urea, and total bilirubin increased, whereas total protein, sodium, chloride, albumin, and inorganic phosphate decreased after exposure. The current study clearly classified MLN as highly toxic to rohu. Therefore, the extra-judicious use of MLN should be strictly supervised. Studies concerning the real-world concentration of pesticides should be carried out on regular basis to mitigate the echoing issue of pesticide-based pollution.