Evaluation of Leached Heavy Metals Using Various Leaching Agents in Self-Produced Ceramics

This study was aimed at evaluating the leaching ability of self-produced glazed ceramic food wares produced from locally available raw materials. The raw materials (rice husk, quartz and feldspar) were acquired from various locations within Bauchi, Bauchi State, Nigeria, while silt stone was obtained from Numan River Basin, Adamawa State, Nigeria. Leaching tests on the self-produced ceramics were conducted using various leaching agents (4.00 % acetic acid, boiled water, orange juice, boiled lipton tea and 1.00 % lactic acid). The levels of heavy metals leached in the self-produced ceramics/leaching agents were determined using Buck Scientific Atomic Absorption Spectrophotometer Model 210 VGP. The levels of nickel, chromium, manganese, cobalt, zinc, cadmium and lead (µg/cm3) determined in the various leaching agents respectively ranged from 0.01 in lactic acid to 0.15 in lipton tea; not detected in lipton tea to 0.14 in boiled water; 0.09 in acetic acid to 2.70 in lipton tea; 0.06 in lactic acid to 1.47 in lipton tea; not detected in acetic acid, boiled water, orange juice and lipton tea to 119.20 in lactic acid; 0.01 in acetic acid to 0.26 in lactic acid and 0.04 in orange juice to 1.03 in lipton tea. The concentrations of the heavy metals leached in the self-produced ceramics are mostly below their safe permissible limits. Ceramics of low levels of heavy metals leaching ability are therefore produced and hence safe for human utilization and consumption.