Toxicological manifestations in gills, liver, kidney and muscles of Channa punctatus exposed to mercuric chloride

Abstract

Aquatic regimes are exposed to a variety of pollutants that are mainly released by anthropogenic activities. Mercuric chloride (HgCl2) pose serious hazards to freshwater fish resource for its toxicity and long persistence. It is also a threat to humans who consume fish as a food resource. This study aimed to determine the consequences of acute exposure to HgCl2 in the freshwater food fish Channa punctatus (Bloch, 1973). The acute study of 96 hours was composed of three groups (in triplicates), having ten fish in each group which includes group I (control), group II (0.112 mg/l of HgCl2) and group III (0.224 mg/l of HgCl2). Results showed induction in reactive oxygen species (ROS) level in erythrocytes of group III (22159 ± 258.036). The biomarkers of oxidative stress, glutathione reduced (GSH) and lipid peroxidase (LPO) showed significant (p < 0.05) decrement and increment in their activity, respectively, in gills, liver, kidney and muscle tissues of the fish treated with HgCl2. Further, micronuclei (MN) and nuclear abnormalities (NAs) were formed in the erythrocytes of the fish of groups II and III, revealing DNA damage, hence showing genotoxicity. Histopathological studies in sample tissues of HgCl2 treated group demonstrated irreversible tissue injuries and anomalies. Thus, the findings from the study demonstrate that biological stress is induced in fish because of acute exposure to HgCl2, leading to health impairment