Physicochemical processes involved in migration of bisphenol A from polycarbonate

Abstract Results of experiments, conducted by different polycarbonate (PC) producing companies, on migration of bisphenol A (BPA) from PC into different liquids, were supplied to the author for compilation, review, and discussion. The observed BPA migration levels were found to be nearly independent of the concentration of residual BPA in the PC resins. Hydrolysis of PC is the dominant mechanism responsible for the release of BPA from the polymer surface into the contacting aqueous liquid. Experiments with PC spiked with deuterated BPA revealed that diffusion‐controlled migration play a minor role in the overall release of BPA from PC. The influence of a number of experimental parameters on the migration of BPA into aqueous liquids was studied. Factors found to be of importance included the temperature, pH, and ozone concentration of the liquids, as well as the surface ageing of the PC. All of the BPA migration levels obtained from experiments performed under standard conditions as given in the EU legislation and its associated guidance documents were found to be well below the EU specific migration limit of 600 μg/kg food which applies to plastics in contact with foodstuffs (EU Directive 2002/72/EC as amended). Migration is lower in oil than in the aqueous food‐simulants water, 3% acetic acid, and 10 or 50% ethanol. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009