ASSESSMENT OF SOME HEAVY METALS IN SOIL SAMPLES ALONG GUTTERS IN NKPOR, ANAMBRA STATE
ABSTRACT
Ten representative soil samples were collected along major gutters within Nkpor metropolis. The soil samples were digested using mixtures of HF and aqua regia in ratio1:1. The heavy metals contents of the digested soil samples were determined via Flame Atomic Absorption Spectrophotometer FAAS. Sample A had the highest concentration of heavy metal and the trend was Ni > Cr > Hg > Zn > As ~ Cd, it was followed by sample B with Ni > Cr > Zn > Zn > Cd >g > As, sample C had Ni>Cr >Zn>Hg>Cd>As, sample E had Ni > Zn > Cd > Cr > Hg > As. While sample D had Cr > Ni > Zn > Cd > Hg > As. Also the results of the sequential extraction of each soil sample indicated that Ni had the highest percentage bioavailability (49.61%), Hg (47. 72%), Cr (42. 19%), Zn (39.66%), Cd (35.10%), As (0.00%). The high concentration of Hg, Cr and Cd in most areas of the metropolis indicated gross contamination, which could have resulted from human activities, hence the need to adequately monitor the release of these toxic metals to the environment.