STUDIES OF MIGRATION OF POTENTIALLY GENOTOXIC COMPOUNDS INTO WATER STORED IN PET BOTTLES

Coloured polyethylene terephthalate (PET) bottles for carbonated bever ages were studied for potential migration of genotoxic compounds. A co mbined approach, using physicochemical methods and a bacterial short-t erm mutagenicity test (Ames test) was followed. Standard EEC and US FD A tests for total migration of non-volatile migrant compounds into dis tilled water were performed, together with modified tests, where freez e-drying instead of evaporation of water was used, in order to measure both volatile and non-volatile chemicals. Gas chromatography-mass spe ctrometry (GC-MS) analysis was performed on these residues. PET bottle s filled with naturally carbonated mineral water were also used for lo ng-term total organic carbon (TOC) and mutagenicity migration studies (up to 6 months' storage). Total migration results for PET bottles wer e within the EEC and US FDA limits. The use of freeze-drying for the e limination of water enabled much higher total migration data (higher t han the limits) to be revealed. Some potentially genotoxic compounds ( acetaldehyde, dimethyl terephthalate, terephthalic acid) were identifi ed in these migrant compounds by CC-MS analysis. The tests for TOC mig ration gave a maximum value after 2 wk storage and the mutagenicity te sts on non-volatile migrant compounds gave always negative results.