Objective: To assess the risk of bisphenol A (BPA) exposure when infants suck or chew infant books, the concentration of BPA leaching from infant books published by Japanese makers to artificial saliva was measured.
Methods: The concentration of BPA leaching from 10 infant books to 15 ml artificial saliva or water was measured at 37°C for 20 hrs. BPA concentration was measured by high-performance liquid chromatography-electrochemical detection (HPLC-ECD) with solid-phase extraction.
Results: BPA was leached from all books when pieces of them were dipped both into saliva and water for 20 hrs. The highest concentration of BPA leaching from one out of 10 books was 43.4 ng/ml (for 2 hrs) in saliva, which was estimated to be approximately 0.052 mg/kg body weight/day for infants aged 6–10 months.
Conclusion: As BPA has endocrine-disrupting effects and poses higher risks in infants than in adults, it is desired to reduce BPA use in the printing of infant books from the viewpoint of child health.