Local textile industry wastewater effect on freshwater fish species

Abstract

The effect of local tie-dye textile industry wastewater on two selected fish species (Clarias gariepinus and Oreochromis niloticus) of economic importance was investigated using static renewal bioassay method to determine the acute and sub-lethal effects on the test fish species. The physico-chemical parameters of the tie-dye wastewater used for the different bioassays were found to be significantly different (p < 0.05). The C. gariepinus and O. niloticus adults were found to have 96 h-LC₅₀ values of 17.58 and 4.66 % respectively while the 96 h-LC₅₀ of the fingerlings of C. gariepinus and O. niloticus had 1.70 % and 1.85 % respectively. Sub-lethal exposure of the adult fish to the tie-dye wastewater revealed that the following haematological parameters: packed cell volume (PCV), haemoglobin (Hb), red blood cell count (RBC), glucose and total protein were significantly (p < 0.05) affected. This study has revealed that untreated wastewater discharged into the aquatic ecosystem has the potential to adversely affect the physical and chemical parameters of the water bodies which can be harmful to aquatic biota especially at the point of discharge. Thus, there is a need to treat the tie-dye wastewater before being released into the aquatic ecosystem.

Key Words: Bioassay, Clarias gariepinus, Oreochromis niloticus, haematological parameters, tie-dye wastewater.