Chapter 3G: Bisphenol A

Bisphenol A (BPA) is a chemical widely used in the manufacture of polycarbonate plastics and epoxy resins and it is often used as an additive in many other plastic products. The majority of products containing BPA are used for either food packaging, or for products directed at food or beverage storage by consumers. Because of the endocrine disrupting potential of BPA, regulations to limit the population exposure have been imposed in some countries, especially for products in contact with infants and small children. BPA interacts with human hormone receptors and has been shown to elicit responses even in low concentrations. The concern about BPA exposure is primarily directed towards the exposure of unborn babies, infants and young children because they are at the most sensitive stages in life. Animal studies with rodents have shown several adverse effects on the offspring even at environmentally relevant doses of BPA. Biomonitoring studies have primarily measured the BPA concentration in urine; however, measurements on blood samples, breast milk, follicular and amniotic fluids along with placental measurements have also been conducted. The presence of BPA in all the different media has clearly shown that humans are exposed to BPA, and that BPA can be found in human samples in spite of its rapid metabolism. Furthermore, BPA in the amniotic fluid, placenta and umbilical cord blood has revealed that fetal exposure to the chemical also occurs. Further biomonitoring studies of BPA linking the exposure to possible health effects in humans will help to clarify the risk of the current exposure levels.