Acute toxicity analysis of effluent from tannery industry in Kano metropolis

Abstract

The acute toxicity of tannery effluents collected from Challawa industrial estate Kano, Nigeria was assessed using Artemia salina and Clarias gariepinus. The test was done after the evaluation of range finding test before a definitive test with 3 replication of each treatment. The varying concentrations were prepared by diluting crude effluent with borehole water on V/V% in a completely randomized design. The experiment showed C. gariepinus fingerling to exhibit abnormal behavior such as initial erratic movement, skin discolouration and loss of reflex. Recorded mortality and behavioral abnormalities in both species observed were dose-time-dependent. The 96 hours LC₅₀ estimated for C. gariepinus was 9.95% while that of A. salina after 24 hours and 48 hours were 4.63%, 0.73% respectively. Thus, the information from the study demonstrates the toxic effect of tannery effluent which requires proper management before its discharge into environment.

Keywords: Acute toxicity, Artemia salina, Clarias gariepinus, Effluent, Tannery