Bisphenol A is now deeply imbedded in the products of modern consumer society, not just as the building block for polycarbonate plastic (from which it then leaches as the plastic ages) but also in the manufacture of epoxy resins and other plastics, including polysulfone, alkylphenolic, polyalylate, polyester-styrene, and certain polyester resins.
Its uses don't end with the making of plastic. Bisphenol A has been used as an inert ingredient in pesticides (although in the US this has apparently been halted), as a fungicide, antioxidant, flame retardant, rubber chemical, and polyvinyl chloride stabilizer.
These uses create a myriad of exposures for people. Bisphenol A-based polycarbonate is used as a plastic coating for children's teeth to prevent cavities, as a coating in metal cans to prevent the metal from contact with food contents, as the plastic in food containers, refrigerator shelving, baby bottles, water bottles, returnable containers for juice, milk and water, micro-wave ovenware and eating utensils.
Other exposures result from BPA's use in "films, sheets, and laminations; reinforced pipes; floorings; watermain filters; enamels and vanishes; adhesives; artificial teeth; nail polish; compact discs; electric insulators; and as parts of automobiles, certain machines, tools, electrical appliances, and office automation instruments" (Takahashi and Oishi 2000).
BPA contamination is also widespread in the environment. For example, BPA can be measured in rivers and estuaries at concentrations that range from under 5 to over 1900 nanograms/liter. Sediment loading can also be significant, with levels ranging from under 5 to over 100 Β΅g/kg (ppb) BPA is quite persistent as under normal conditions in the environment it does not readily degrade (Rippen 1999).
What this all means is that most of your life you are within arm's length or closer to bisphenol A. No wonder the debate over its toxicity is so intense.
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