A03028: Investigation into the migration of metals and coating materials from kitchenware products
Wednesday 18 June 2003
This research project aims to determine the chemicals from non-stick coated and metal-coated kitchenware products that could migrate into food.
Background
A range of kitchenware products is commercially available and is used in contact with foods under a variety of exposure conditions. For the purposes of this study kitchenware products were defined as cookware articles intended for oven and/or stove top use, i.e. pans, cake tins, etc.
The aim of this project was to determine the migration of potential contaminants from non-stick coated and metal-coated kitchenware products.
The diversity of kitchenware products commercially available continues to increase, yet little is known of the processes and materials involved in their manufacture and the safety of these items. Much is known about the leaching of lead and aluminium, but other metals may migrate. In addition a variety of kitchenware products exist with non-stick coatings. The migration of any substances present in these coatings also needed to be investigated to ensure the safety of such products.
Research Approach
Non-stick coated products
Information on the uses of non-stick coatings was obtained from coating manufacturers and observations in retail outlets. Based on this, 26 non-stick coated samples were purchased giving a variety of products, coating/metal types and food contact applications. The coating type was identified and the solvent extractables determined. Coating materials were analysed by a range of techniques. Worst case migration was determined and exposure calculated and compared with the Acceptable Daily Intake (ADI)/Tolerable Daily Intake (TDI) for these substances. Overall migration into food simulants was also measured. Migration of bisphenol A and several phthalates was tested using food simulants.
Metallic kitchenware products
Work in this project was carried out to confirm the applicability of previous recommendations, for testing metal release from kitchenware products, proposed in the recently published project report ‘Migration test protocols for the electroplated and dipped metalware intended for food contact’.
Results and findings
Non-stick coated products
Screening studies detected a range of compounds in the total ion chromatograms of solvent extracts obtained from the 26 products investigated. Tentative identifications were made by comparison with Wiley library spectra and several were confirmed by the analysis of standard compounds. Exposure to any of the tested substances in this kitchenware should not cause a health risk – the ADIs/TDIs would not be exceeded if the chemicals migrated into food.
Indeed, none of the products exceeded a draft overall migration limit of 10 milligrams per decimeter squared (Council of Europe Resolution AP (96) 5 on surface coatings intended to come into contact with foodstuffs).
Metallic kitchenware products
The work carried out confirmed the practicality of the following recommendations for testing metal release from kitchenware products:
- For articles which may be used with acidic foodstuffs, testing for the release of toxic metal ions (e.g. lead, cadmium, mercury) should use three successive exposures to 4% acetic acid in distilled water under test conditions of 24 hours at 25oC.
- For articles which may be used with acidic foodstuffs, the results for release of other metal ions (e.g. tin, iron, chromium) should be the average of those for the first three exposures to 4 per cent acetic acid in distilled water (24 hours at 25oC).
What it means and why it's important
This project has identified the potential migrants present in 26 non-stick coated kitchenware products intended for food contact applications. The levels of these substances in the coatings and in food simulants exposed to these products, were generally low and within safety limits.
The test protocol proposed in project A03007 is suitable for testing metal kitchenware products.
Dissemination information
Final report is available from the FSA Library and Information centre. To obtain a copy, please contact the Enquiry Desk, Dr. Elsie Widdowson Library and Information Services, Food Standards Agency (020 7276 8181/8182 or at library&info@foodstandards.gsi.gov.uk).
See Also