Acute toxicity and residue analysis of cartap hydrochloride pesticide: Toxicological implications on the fingerlings of fresh water fish Labeo rohita

The extensive use of cartap, a water soluble carbamate pesticide, raises the possibility of its undesirable toxicity to non-target organisms. Agricultural run-off and vector control sprays are the major sources of exposure to this pesticide for fresh water aquatic organisms. We therefore hypothesized that these sub-lethal yet environmentally significant concentrations of cartap has toxicological implications on fingerlings of Labeo rohita. The rationale of the study was to assess biochemical, histological responses and residue analysis in vital organs of L.rohita exposed to cartap hydrochloride after 24, 48, 72 and 96 h of exposure. An attempt has been made to elucidate the sub-lethal toxicity of cartap exposure on biomarker enzymes related to vital organs of L. rohita. The results clearly exemplify that exposure to sub-lethal concentration of cartap (0.3551 mg/L−1 for 96 h) was reflected in tissue concentrations of pesticide with significant alterations in the biomarker enzymes Acetylcholineesterase activity(AChE), Alanineaminotransferase(ALAT), Asparatateaminotransferase(AAT), alkaline phosphatase(ALP) and superoxide dismutase(SOD). Increased abnormalities in the liver function test coupled with an augmented antioxidant stress response (SOD activity) were noticeably observed in gills, liver and brain respectively. The presence of total cartap pesticide residues in fish tissue were determined by reverse phase high-performance liquid chromatography coupled with UV-detector. The LOD and LOQ of cartap residues in the exposed tissue samples were determined as 0.1(µg/L) and 0.012(µg/L) respectively. However, the tissue injuries were clearly evident from the morphological and nuclear anomalies in the hematoxylin and eosin stained sections of gill, liver and kidney suggested that cartap is moderately toxic to the L. rohita.