Investigation into the migration potential of coating materials from cookware products

Twenty-six non-stick-coated cookware samples were purchased, covering a variety of products, coating/metal types and food contact applications. The polymer coatings were identified to be polyethersulphone, polytetrafluoroethylene (PTFE), bisphenol A/epichlorohydrin and one coating for which no good match was obtained with infra-red library spectra. All of the products intended for stove-top use had a polymer coating containing PTFE. The coatings were analysed as purchased and after heating at 250°C for 30 min to simulate actual conditions of use. Total solvent extractables were measured and the overall migration was determined into simulants. None of the products exceeded an overall migration limit of 10 mg dm^-2. Coating materials were analysed by headspace gas chromatography-mass spectrometry (GC-MS), by liquid extraction followed by GC-MS and by liquid extraction followed by liquid chromatography-mass spectroscopy with a particle-beam interface. Benzene was detected in two samples, at 1.4 and 2.4 µg dm^-2. These levels in the coatings are too low to give any detectable migration into foods. There was no detectable release of perfluorochemicals. Several other substances were identified and the worst-case migration was calculated. The origin of many of the substances detected was considered to be by pick-up from the printed packaging materials in which the cookware was sold. Potential consumer exposure was calculated. None of the substances identified had the potential to exceed their tolerable daily intake (TDI) value. To confirm these worst-case calculations, the migration of certain phthalates and of bisphenol A was measured into food simulants. Migration levels were very low.