Assessment of Heavy Metals in Ground Water from Nasarawa State, Middle Belt, Nigeria

Abstract

Aim: To assess contamination of borehole water by heavy metals (Fe, Zn, Pb, Cr, Cu, Ni, Mn). Study design: Water samples collected from fifty two boreholes in twelve Local Government Areas (L.G.A) of Nasarawa State were analyzed for the heavy metal concns. Place and Duration of Study: Samples were collected from Akwanga, Awe, Doma, Garaku, Karu, Keana, Keffi, Lafia, Nasarawa, Nasarawa Eggon, Toto, and Wamba, during the dry season. Methodol.: The water samples were prepd. according to std. methods. Heavy metal levels in the samples were quant. detd. using at. absorption spectrometry (AAS). Results: The highest concns. of Zn (1.81 ± 1.19 mg/l) and Fe (0.89 ± 1.73 mg/l) were recorded at Keana, while their lowest levels were obsd. at Lafia. Pb ranged from 0.01 ± 0.00 to 0.04 ± 0.05 mg/l in the areas. The highest Cu (0.32 ± 0.51 mg/l) and Ni (0.07 ± 0.06 mg/l) contents were obtained at Doma. Nasarawa recorded the highest concn. of Mn (0.08 ± 0.04 mg/l) and the lowest at Lafia (0.01 ± 0.00 mg/l). Water Cr contents was highest at Keana (0.24 ± 0.32 mg/l) and lowest at Lafia and Akwanga. Ni levels were low. Anal. of Variance (ANOVA) indicated that heavy metal concns. were not significantly different (P