Concentrations of Heavy Metals in Some Important Rivers of Owerri Zone, Imo State, Nigeria

Abstract

Analyses of heavy metals in water samples from different rivers of the Owerri zone in Imo State, Nigeria were carried out using Atomic Absorption Spectrophotometer (AAS). Water samples from Rivers Azaraegbelu, Ogochie, Okatankwu and Otamiri were analyzed for lead (Pb), arsenic (As), cadmium (Cd) and zinc (Zn). The concentration of lead was highest in water samples from Azaraegbelu River (0.054 ppm). Arsenic was present in lower concentration in Azaraegbelu, Ogochie and Okatankwu Rivers. Cadmium concentration was 0.511 ppm in Azaraegbelu River, 0.034 ppm in Ogochie River, 0.091 ppm in Okatankwu River and 0.166 ppm in Otamiri River. Concentration of Zinc was higher in Azaraegbelu River (0.288 ppm), while Ogochie River recorded the lowest concentration of 0.098 ppm. Comparatively, Azaraegbelu River recorded the highest concentration values of the heavy metals analyzed.

Keywords: Heavy metals, concentration, river, pollution, bioavailability, toxicity