Migration of Tinuvin P, a UV stabilizer, from PET bottles into fatty-food simulants

Tinuvin P migration from Polyethyleneterephthalate (PET) bottles was invest igated using several fatty-food simulants such as olive oil, soybean oil, n -heptane and iso-octane, at exposure conditions of 2-10 days at 40 degrees C (total immersion). The stability of several UV stabilizers (BHT, Cyasorb UV 5411, Tinuvin P, Tinuvin 326 and Tinuvin 327) in n-heptane and iso-octan e was also studied. After 10 days at 40 degrees C, losses of 6% and 20% in iso-octane and n-heptane respectively, were verified for Tinuvin P. Other U V stabilizers at the same experimental conditions showed higher losses (up to 30% for Tinuvin 327). These results confirm that, when carrying out spec ific migration studies, the stability of the substance of interest should b e established in the food simulant to avoid underestimating the real migrat ion behaviour. In order to quantify UV stabilizer migration, n-heptane and iso-octane solutions were concentrated and directly analysed by SIM mode GC -MS. For olive and soybean oils, Tinuvin P was isolated using size-exclusio n chromatography and quantified by SIM mode GC-MS. Iso-octane proved to be a move suitable fatty-food simulant than n-heptane for the migration study of Tinuvin P from PET. Higher levels of Tinuvin P migrated to olive and soy bean oils rather than to n-heptane. These results suggest that the MERCOSUL recommended official methods for specific migration studies should be revi sed since the migration levels using n-heptane as a fatty-food simulant cou ld be underestimated when compared to edible oils. Copyright (C) 1999 John Wiley & Sons, Ltd.