Migration of metals from ceramic food contact materials. 1: Effects of pH, temperature, food simulant, contact duration and repeated-use

Abstract The Directive 84/500/EEC is the legislation stating the requirements for ceramic articles intended to come into contact with food. A revision of the Directive focusing on lowering the specific migration limits of lead and cadmium, on establishing an appropriate testing method and on extending the scope of the Directive to other metals is currently under consideration by the European Commission. In this context, this study investigated the extent to which various parameters (nature of the acid used as food simulant, pH, temperature, repeated use and contact duration) influence the release of metals from ceramic articles during their use. The following results were observed: a) comparable quantities were extracted by acetic acid and citric acid; b) the amounts of metals released in solution increased with decreasing pH; c) successive migrations showed a significant drop in the amounts of metals released between the first and subsequent migrations; d) the amounts of metals released from ceramic ware increased quickly at short times before leveling off to a plateau; e) high temperatures promoted the migration. The suggested elements to be added in the Directive and suitable testing conditions for the migration test are discussed.