Tea brewed in traditional metallic teapots as a significant source of lead, nickel and other chemical elements

Abstract

An environmental inquiry conducted by the Brussels Inter-communal Laboratory of Chemistry and Bacteriology (BILCB) has revealed that in 2000 a traditional metallic teapot caused in Brussels lead intoxication among a family of Morocco origin. Following this case study of lead poisoning and subsequent preliminary results carried out by the BILCB, which confirmed the dangerousness of this kind of item, samples of traditional metallic teapots were collected from North African groceries in Brussels by the Institute of Public Health (IPH) in collaboration with the BILCB and the Federal Agency for the Safety of the Food Chain (FASFC). Aluminium, copper, iron, nickel, lead and zinc were analysed to identify metals with a potential to migrate into tea solutions. Simulants (natural tea, tea acidified with citric acid and citric acid) were brewed in those teapots in order to identify the leaching potential of migration at boiling point temperature for different contact periods. Multi-elementary analysis was carried out by inductively coupled plasma-atomic emission spectrometry (ICP-AES). It was concluded that the concentrations of those leached metals depend on the nature of the migration liquids, the type of teapots and the contact periods. Most teapots showed a high level of toxic metals in leachates for lead and to a less extent for nickel, which can contribute significantly to the risk of serious poisoning. A comparison of the results with the toxicological reference values was done. The teapots were withdrawn from the market by the FASFC.

Keywords:

• metals analysis – ICP
• food-contact materials
• food simulants
• migration
• toxic elements
• beverages

Acknowledgements

This work benefited from the help of Dr Petit of the Inter-communal Laboratory of Chemistry and Bacteriology (BILCB) and with of the Provincial Unit of Control (UPC), Brussels, and from the Federal Agency for the Safety of the Food Chain (FASFC), which by its kind collaboration allowed the culmination of this work.