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Not even all government agencies agree with the FDA. The National Toxicology Program has expressed "some concern" that BPA alters the brain, behavior and prostate in fetuses and children. Then early in 2008, a report released by the Department of Health & Human Services' Toxicology Program raised concerns of "the possibility that bisphenol-A may alter human development cannot be dismissed."
The Concerns
Here's what all the fuss is about: BPA is an endocrine disrupter. It mimics the hormone estrogen in the human body, by latching onto the same cellular sensory molecules that natural estrogens stimulate. It's also something that is easily absorbed into the body. During the manufacturing process, not all BPA gets locked into chemical bonds with the plastic. The residual that is left over can work itself free, especially if the plastic is heated. This can happen in a dishwasher, a microwave, or even a plastic container such as a water bottle that's been left in the sun. As a result, this estrogen like chemical leaches into the foods we eat, the liquids we drink, and is absorbed into our body. The chemical can even be absorbed through the skin by contact with plastic or inhaled in the form of microscopic bits of dust. Hence the 93% rate of positive tests for the chemical in the bloodstream of adults and children. While the kidneys of mature children and adults are able to quickly eliminate the chemical from their bodies, newborns and younger children have a tendency to retain it for longer periods of time. Combine these factors with a rate of constant and continual exposure, and you understand why scientists are worried that BPA may be adversely effecting child development.
BPA first came in use as a synthetic estrogen in the 1930s. While its use in humans soon died out, chemist's discovered the chemicals knack for strengthening plastics, and the rest is history. Soon it was commonly used in a variety of plastic products, and became a part of our everyday lives.
The potentially harmful effects of BPA, like so many other scientific discoveries, were originally stumbled upon by accident in 1998.5 Geneticist Patricia Hunt was doing studies on mice reproduction when she started getting some unusual results. After every other possible culprit was explored, she discovered the underlying problem: a janitor had used an abrasive chemical on the floor, and as a result, the mice were exposed to significant levels of BPA.
Since then, BPA has been implicated in a number of potentially harmful effects, most all of these in animal studies. In 2007 Hunt co-authored a paper in the science journal PLoS Genetics that exposed pregnant mice to BPA just as the ovaries in their developing female fetuses were producing their lifetime supply of eggs. When these fetuses became adults, 40% of their eggs were corrupted, which meant trouble for their offspring as well. "With that one exposure, we're actually affecting three generations simultaneously," she says. A number of other studies have also found that BPA tinkers with reproductive systems. In male offspring the extra artificial estrogen causes prostate and hormone gland problems. In females, the extra estrogen throws off body chemistry and can trigger an early start to puberty. This has led many to speculate, perhaps
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