Assessment of Leachable Toxic Metals in Glazed Ceramic Dinnerware’s in Ibadan, Southwestern Nigeria

Abstract

This study investigates the presence and leaching potential of some toxic metals (Pb, Ni, Cd and Cr) from ceramic dinnerware’s commonly found in Nigerian households. A total of 104 ceramic cups-32, bowls-36 and plates-36 of different colours where subjected to metal leaching using 4% acetic, 1% citric, 1% lactic acids and hot water across a period of 1 to 5days. Average leached Pb from cups, bowls and plates range between 0.026±0.01 to 0.047±0.04 mg/L while leached Ni range between 0.033±0.03 to 0.056±0.02mg/L. Cadmium and chromium levels were relatively insignificant and undetected. Concentrations of Pb and Ni from the ceramic wares were related to colour and leaching time. Blue, brown and green ceramics were found to potentially leach more metals and concentration increase with increasing leaching time. Average Pb levels in wares for the four leaching solutions were within Food and Drug Administration action level of 0.5-3.0mg/L, but slightly exceeding Standard Organization of Nigeria’s permissible limit of 0.01mg/L. In conclusion, the ceramic wares pose little or no potential health risk. However, constant monitoring is essential to avert associated health risk arising from prolong contact of consumables (foods and drinks) with glazed ceramic wares.