Migration of lead and cadmium from ceramic kitchenware and estimation of sampling uncertainty

Abstract

The aims of this study were (i) to evaluate the existing analysis capacity for lead and cadmium leached from ceramic articles, (ii) to determine the migration of lead and cadmium from glazed ceramic kitchenware sold on the Turkish market, (iii) to estimate the sampling uncertainty. Traditional ceramic cooking ware and Chinese breakfast hollowware were sampled randomly from different sales points located in Bursa in 2018 (n = 96). Ceramic articles were subjected to the migration conditions specified in the legislation, and the amount of lead and cadmium was determined with the inductively coupled plasma and mass spectrometry. It was found that the current analytical method can quantify lower levels of the metals with acceptable method performance parameters. The amount of the metals migrated were far below the current permissible limits set in the legislation. Relative sampling uncertainty was estimated as 66.1% and this result was related to the heterogeneity within a lot. Practical applications Lead and cadmium are used to coat the ceramic kitchenwares during the glazing process. If ceramic kitchenware are produced under good manufacturing conditions and the glaze is undamaged, the migration of lead and cadmium may be lower than the permissible limits set in the legislation. Migration analysis based on inductively coupled plasma mass spectrometry (ICP-MS) provides high selectivity, sensitivity, and low analytical limits. Considering inevitable sampling uncertainty, at least four articles should be taken from a lot for migration analysis.