MIGRATION OF RESIDUAL CONTAMINANTS FROM SECONDARY RECYCLED POLY(ETHYLENE-TEREPHTHALATE) INTO FOOD-SIMULATING SOLVENTS, AQUEOUS-ETHANOL AND HEPTANE

This study measured the migration of benzene, butyric acid, dodecane, octadecane, tetracosane, diazinon, lindane, and copper(II) ethyl hexan oate from poly(ethylene terephthalate) (PETE) sheets into the food sim ulants, 8% ethanol/water and n-heptane, The contaminated PETE sheets w ere extruded from PETE chips that had been previously contaminated but were washed, dried, and remelted. The level of these contaminants rem aining in the extruded sheets ranged from benzene at 0.6 mg/kg to copp er salt at 24 mg/kg. The extraction data demonstrate that migration of the residual contaminants from the extruded PETE sheets resulted in c oncentrations lower than 10 mu g/kg in the food simulants. At very hig h residual concentrations of butryic acid (147 mg/kg) and benzene (218 mg/kg) in sheets made from unwashed PETE, higher amounts of the conta minant migrated into the food simulants. This migration resulted in co ntaminant concentrations exceeding 10 mu g/kg and suggests that unwash ed recycled PETE may not comply with FDA reguirements. The crystallini ty of extruded PETE sheets in this study ranged from 5 to 15%, which i s lower than that of most commercial PETE (30%). Therefore, the migrat ion data obtained from these test samples represent the most severe co nditions for conservative exposure evaluations.