Methods to Determine Partition Coefficient of Organic Compounds in Water/Polystyrene Systems

Three experimental techniques were employed to determine the partition coefficient (K) of toluene, d-limonene, and ethyl acetate between water and polystyrene. These techniques were gas chromatography, (GC) gel permeation chromatography (a novel approach), and a dynamic thermal stripping-thermal desorption procedure. Comparative results of K values, range of applicability and the limitations of each technique were determined. GC was very suitable for systems showing high K values, while gel permeation chromatography was excellent for direct measurement of sorbed compounds. Statistical analysis of results and kinetics of the sorption process were included. Values of K were 800 for toluene, 5100 for d-limonene and 1.9 for ethyl acetate.     

EVALUATION OF PLASTICS PACKAGING MATERIALS FOR FOOD PACKAGING APPLICATIONS: FOOD SAFETY CONSIDERATIONS

In evaluating a packaging system for food packaging applications, consideration must be given to the physical properties, chemical composition and extractivity of the packaging material. The last point, extractivity, or migration from the packaging material to a food contact phase, is of major concern in the selection and use of plastics packaging materials for food packaging.
The present article deals specifically with migration of indirect food additives from plastics packaging materials and the scientific principles related to migrant transport or diffusion, as they apply to food safety. These principles and their experimental basis are discussed.