Prenatal Origins of Endocrine Disruption
Critical Windows of Development
What is Bisphenol A?
Bisphenol A (BPA) was synthesized in 1891 and first recognized as a synthetic estrogen in the 1930s. Chemists later discovered that the individual monomers of BPA could be combined to make two kinds of plastics: polycarbonate and epoxy resins. Commercial production of BPA began in the 1950s when large-scale uses for these products were developed.
BPA-based polycarbonates are used in products such as baby bottles, water bottles, eyeglass lenses, medical equipment, toys, CDs/DVDs, cell phones, consumer electronics, household appliances, sports safety equipment, airplanes, and automobiles. Epoxy resins containing BPA are used as liners for most food and beverage cans, adhesives, industrial protective coatings, and automotive primers. BPA is also used to make dental sealants and flame retardants, and is an additive in many other widely used consumer products. It is one of the highest volume chemicals produced worldwide with an expected global production of 12 billion pounds per year by 2011.
How does Bisphenol A get into our bodies?
‘Leaching’ occurs when the chemical bond linking BPA monomers together to form plastic (i.e., polymerization) breaks. BPA is ingested when it leaches into food and beverages for human consumption. Heating cans to sterilize food, storing acidic or basic food/beverages in cans or polycarbonate plastic, and repeated washing of polycarbonate products all increase the rate at which leaching occurs.
The human body can metabolize and excrete BPA relatively rapidly. Yet a recent study by the U.S. Centers for Disease Control and Prevention, that looked at urinary concentrations of BPA in over 2500 participants, indicated that 93% of U.S. residents have measurable amounts of BPA in their bodies. This suggests that exposure is continuous and via multiple sources.
Where can I find more research on Bisphenol A?
In addition to the research presented in the Critical Windows of Development on prenatal exposure to BPA, TEDX has an extensive database of scientific literature on prenatal and postnatal BPA exposure, with summaries, graphs and analyses of the data. Click here to go to our Bisphenol A webpage.