Heavy Metals Assessment of Abattoir Effluent on Surface Water Quality of River Katsina-Ala of Benue State, Nigeria

Water samples of six sampling sites (two downstream, two abattoir sites and two upstream sites) were analyzed using standard methods to determined and assessed heavy metal content of abattoir effluent on surface water quality of River Katsina-Ala, Benue State, Nigeria for rainy and dry seasons. Rainy season heavy metals results were; Cr6+ (0.032+0.06mg/l); Mn2+ (0.16+0.034mg/l); Cu2+ (0.86 +0.46mg/l); Pb2+(0.006+0.002mg/; Cd2+(0.0023+0.004mg/l) and the dry season results were: Cr6+(0.028+0.007mg/l); Mn2+(0.07+0.05mg/l); Cu2+(0.85+0.16mg/l); Pb2+(0.0030+0.014mg/l); Cd2+(0.0021+0.012mg/). Most heavy metals for both seasons were within the maximum permissible limit set by Federal Ministry of Environment, Nigeria (1991). The mean concentrations of Zn2+(1.70+0.29 mg/l) for rainy season and Zn2+(1.33+0.23mg/l) dry season were above the control, and standard safe limits of < 1mg/l FMEnv (1991) for surface water quality. There was no significance difference between the means from upstream and downstream sites for both seasons; though significance difference existed at the abattoir sites. River Katsina-ala is slightly polluted. Heavy metal content from effluents from abattoir contributed to upset the physicochemical balance of the river.