Toxicity effects of waste dry cell battery on the haematology and biochemistry of blood, gills and liver of Clarias gariepinus fingerlings

Indiscriminate dumping of spent dry cell batteries have continuously polluted aquatic environments usually as surface run-offs with deleterious effects on aquatic fauna including Fish. Toxicity effects of water soluble fractions (WSFs) of waste dry cell battery (WDCB) on blood, gills and liver of Clarias gariepinus fingerlings were investigated under laboratory conditions. Acute (96 hr.) and sub lethal (56 days) bioassays were separately conducted on 120no. C. gariepinus fingerlings stocked ten (10) per tank in twelve (12) circular tanks, each in randomized block design. Fish were exposed to acute (0.31, 0.63, 1.25, 2.50 and 5.00 g/L) and sub lethal (0.02, 0.04, 0.07, 0.14, and 0.28 g/L) concentrations with a control (0.00g/L) in replicates. The 96hr. LC₅₀ of WDCB on C. gariepinus fingerlings was 0.84 g/L with upper (1.12 g/L) and lower (0.49 g/L) confidence limits and cumulated to behavioural changes and death of the fish. Significant alterations (P<0.05) in haematological [white blood cells (WBC) packed cell volume (PCV), red blood cells (RBC) and haemoglobin (Hb)] and biochemical [Alkaline phosphatase (ALP), Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT)] parameters of the gills and liver were observed in both toxicity tests. However, no mortality was recorded in sub lethal bioassay. Waste dry cell battery is hazardous to C. gariepinus fingerlings. Therefore indiscriminate disposal of spent dry cell battery should be discouraged in order to safeguard riparian ecosystem and aquatic fauna.