STUDIES ON FUNCTIONAL BARRIERS TO MIGRATION .1. TRANSFER OF BENZOPHENONE FROM PRINTED PAPERBOARD TO MICROWAVED FOOD

This paper reports studies of migration from paperboard used as packag ing for microwave foods. It looks at the possible routes by which migr ants may transfer. Ink components applied to the outer surface of pape rboard packaging can also be present at the inner (potential food cont act) surface. Substances may permeate through the board or transfer wh ile the printed board is stored stacked or on the reel, and may subseq uently transfer to foods. The photoinitiator, benzophenone, has been s tudied as a specific example of this general case. Migration to foods microwaved in paperboard packaging was up to 1000 mu g/kg. Migration u p to 400 mu g/kg occurred during storage prior to microwave heating. T he mechanism of migration depended on the pack design; occurring hy di rect food contact, transient contact with splashed food, or by gas-pha se diffusion through an air gap. These findings have implications not only for the migration of ink components but also for other substances found in board. This is of special interest should substances of conc ern arise in board from the use of recycled fibres.