Arsenic and Mercury Levels in Earthenware Clays in Otsew in Gomoa West District of Central Region of Ghana using Instrumental Neutron Activation Analysis

摘要

This study was conducted to investigate the occurrence and extent of potentially toxic heavy metals, As and Hg in earthenware clay deposits at Otsew in the Gomoa West District of the Central Region of Ghana using the Instrumental Neutron Activation Analysis (INAA) technique. Arsenic concentrations in the clay ranged from 1.55±0.23 to 18.47±2.60 μg/g at S₆ and S₁₀ respectively with a mean of 9.48 μg/g. Arsenic was not detected in sample S₃. Mercury concentration in the clay ranged from 0.030±0.005 to 0.31±0.01 μg/g in S₂ and S₃ respectively, with a mean of 0.14 μg/g. Mercury was however, not detected in S₁₀. The precision and accuracy of the analytical technique (INAA) were assessed by simultaneous activation of reference material IAEA soil-7. The values obtained compared favourably well with the recommended values as Spearman's correlation coefficient was +0.99. The experimental samples were within ±5% of the recommended values. The measurement precision specified by the relative standard deviation was within ±4%.