Bisphenol A, most commonly referred to simply as BPA, is an organic compound found in a number of
commonly used plastics. It was synthesized in the late 19th Century and has since been sued
extensively in polycarbonate plastics and epoxy resins. Although approved by the FDA in the 1970s as safe,
health concerns have been raised about BPA, especially for young children.
Since the 1930s, scientists
have known that BPA mimics estrogen in the body. This mimicry can disrupt various endocrine and hormonal processes.
Many studies have been performed on the effects of BPA in humans, especially in the last decade, with results indicating
possible effects such as neurological disruption, impairment of thyroid function, and changes in breast and prostate tissue
that can make them more susceptible to carcinogens. Perhaps most importantly, these effects have been observed at BPA exposure
levels well below the current human exposure limit set by the FDA.
BPA exposure can happen through
the skin, but most BPA enters the body through ingestion. BPA is used in the plastic lining placed on the
inside of canned foods to prevent contact between the food and the metal can. BPA is also found in a number
of plastic food containers. These plastics can leech BPA if they are exposed to heat or heavy use, for
example if they are microwaved or put into a dishwasher.
Along with many other plastics, BPA-containing
polycarbonates are marked with a resin identification number of 7. This is the number found inside the
triangular recycle symbol.
BPA is of greatest concern for infants and young children.
Formula-fed infants had the highest average BPA concentrations, most likely because both the formula cans and the bottles
may contain BPA.
