Acute Toxicity, Haematology, Plasma Electrolyte Responses and Hepatosomatic Index in Mud Catfish, Clarias gariepinus (Burchell 1822) Exposed to Two Household Surfactants

Abstract

The acute toxicity and sub-lethal effects of the surfactants JIKB and MFLS on Clarias gariepinus were assessed in laboratory bioassays. Acute toxicity was evaluated over a 96-hour period, while sub-lethal effects on plasma electrolytes (potassium K+, sodium Na+, chloride Cl-), haematological parameters (white blood cells WBC, red blood cells RBC, haemoglobin HGB, and haematocrit HCT), and the hepatosomatic index were investigated over 21 days. Results indicated that MFLS (96h LC₅₀ = 0.086 ml/L) was 3.28 times more toxic than JIKB (96h LC₅₀ = 0.282 ml/L). Haematological analysis showed reductions in WBC, RBC, HCT, and HGB values. Plasma electrolyte levels in C. gariepinus exposed to JIKB and MFLS ranged from 146.7 mEq/L to 220.0 mEq/L for sodium, 5.13 mEq/L to 20.7 mEq/L for potassium, and 111.3 mEq/L to 217.3 mEq/L for chloride, with marked dose- and time-dependent increases. Hepatosomatic index values showed significant differences (p < 0.05) at days 7 and 21, but not at day 14 (p > 0.05). Control values for test organisms exposed to JIKB and MFLS at 7, 14, and 21 days were 3.51 ± 0.82, 2.41 ± 1.11, and 2.95 ± 0.22, respectively. Short-term exposure of Clarias gariepinus to low concentrations of JIKB and MFLS significantly disrupted physiological processes, as evidenced by altered haematological parameters, increased plasma electrolyte levels, and variations in hepatosomatic index. MFLS was significantly more toxic than JIKB. These findings highlight the potential environmental risks posed by these surfactants to aquatic life, underscoring the need for careful management and regulation.