Acute Toxicity of Crude Euphorbia tirucalli Latex Extracts to Oreochromis niloticus Juveniles

Abstract

Acute toxicity of crude Euphorbia tirucalli latex extracts to Oreochromis niloticus juveniles was investigated in the College of Agriculture, Lafia. A four day static acute toxicity test was performed to determine the LC₅₀ value of crude Euphorbia tirucalli latex extract for the fresh water fish, Oreochromis niloticus. Various concentrations of the toxicant were prepared as 0.00 ml/L (control), 10 ml/L, 15 ml/L¹, 20 ml/L, 25 ml/L and 30 ml/L respectively. The LC50 values, their upper and lower confidence limits and slope were calculated. The acute toxicity of crude Euphorbia tirucalli latex extract exhibited a positive correlation between fish mortality and exposure periods. It was found that latex of Euphorbia tirucalli had higher piscicidal activity as compared with other synthetic pesticides, organophosphates and pyrethriod for Oreochromis niloticus. Hence, adequate precautions must be exercised when Euphorbia tirucalli latex is being used near fish-inhabiting water reservoirs and/or as ornamental plant.

Keywords: Toxicant, Euphorbia tirucalli, Oreochromis niloticus, haematological parameters, fish death

Journal of Aquatic Sciences 28 (1): 105- 112 (2013)