Investigating the toxicity potential of heavy metals on blood and biochemical indices of desert scraper (Capoeta fusca )

The development and expansion of industrial and agricultural centers has caused an increase in industrial and agricultural wastewaters and their entry into the environment, which will cause widespread damage. The aim of this research is to investigate the effects of heavy metal toxicity on blood parameters, biochemical parameters and liver enzymes of desert scraper (Capoeta fusca). The acute toxicity of studied heavy metals was estimated according to the OECD method. Samples in 5 groups of 20 pieces (one control group) were exposed to the sublethal concentration of different heavy metals and after the end of 28 days, the blood serum of the fishes was collected and its biochemical parameters and liver enzymes were measured by autoanalyzer. The average lethal concentration of cadmium, chromium, cobalt and copper in 96 hours for the studied species is 37.14, 292.49, 106.95 and 10.73 mg/L, respectively. The number of erythrocytes (× 106 mm3) in the blood of fishes exposed to cadmium, chromium, cobalt and copper was 3.4 ± 0.17, 4.5 ± 0.22, 2.9 ± 0.14, and 3.6 ± 0.18, respectively. The number of erythrocytes of fish exposed to cadmium, cobalt and copper is significantly (p < 0.05) lower than the control group (4.8 ± 0.24). The main damages to erythrocytes exposed to cadmium, chromium, cobalt and copper include vacuolation and deformation of erythrocytes. Glucose and cholesterol levels of fish exposed to cadmium, chromium, cobalt and copper metals are significantly (P<0.05) higher than the control group, and triglyceride, protein and albumin levels are decreased compared to the control group. The level of liver enzymes alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in fish exposed to cadmium, chromium, cobalt and copper was significantly (P< 0.05) higher than the control group after 28 days. Therefore, the exposure of the studied species to different heavy metals causes changes in the level of biochemical parameters and liver enzymes In addition, biochemical parameters and liver enzymes can be used as appropriate biomarkers for fish health and for monitoring the quality of aquatic environments.