Migration of bisphenol A into water from polycarbonate baby bottles during microwave heating

A comprehensive migration database was established for bisphenol A from polycarbonate baby bottles into water during exposure to microwave heating. Eighteen different brands of polycarbonate baby bottles sold in Europe were collected. Initial residual content of bisphenol A and migration after microwave heating were determined. Residual content of bisphenol A in the polycarbonate baby bottles ranged from 1.4 to 35.3 mg kg⁻¹. Migration of bisphenol A was determined by placing a polycarbonate bottle filled with water in a microwave oven and heating to 100°C; the level of bisphenol A in the water was analysed by GC–MS. The procedure of microwave heating and analysis was repeated twice for the same bottle and, thus, three migration extracts were prepared for each test specimen. Migration of bisphenol A into water ranged from <0.1 to 0.7 µg l⁻¹. There was no correlation between the amount of residual content of bisphenol A in the bottles and the migration of bisphenol A into water. Furthermore, there was no correlation between the amounts of bisphenol A in consecutive migration extracts. Data show that during three microwave-heating cycles of a baby bottle made from polycarbonate, microwave radiation had no effect on the migration of bisphenol A into water from polycarbonate. All levels found were well below the specific migration limit of 0.6 mg kg⁻¹ specified for bisphenol A in Commission Directive 2004/19/EC.

Keywords

• migration,
• residual content,
• bisphenol A (BPA),
• polycarbonate baby bottles,
• microwave