Controversy over plastic bottles

Several types of plastic containers have recently made disturbing headlines. Under scrutiny is a specific chemical process called Bisphenol A (BPA), used in the manufacturing of class 7 plastics, better known as polycarbonates. Discovered at the end of the 19th century, polycarbonates are valued for their impact resistance, but they also transmit fine particles of their strength-giving BPA to liquid contents. Ultimately, BPA makes its way into the human body.

California, a dozen other states and the U.S. Senate are all currently reviewing bills to restrict the use of BPA plastics. In the case of baby bottles, legislators are aiming for an outright ban. On April 18, Canadian heath minister Tony Clement joined the fray with a 60-day consultation to gather expert opinions on potential BPA regulation.

Represented by the American Chemistry Council, American BPA manufacturers cite rulings of the European Food Safety Authority and a similar Japanese organization that claim BPA to be safe. Partnering up with Plastics Europe and Japan Chemistry Industry Association, they have launched a site called Bisphenol A to help clarify the facts to their advantage. For the members of this alliance, the dangers of BPA are simply myths.

A somewhat more neutral source, Scientific American magazine suggests that the issue is not as clear as the industry would like it to seem. For its part, the Canadian Cancer Society is very concerned about uncovering possible links between BPA and certain types of cancer that have appeared in people exposed to it.

Contradictory studies

According to its detractors, the presence of BPA in the blood is particularly harmful to hormone function. If this is the case, BPA could be a key cause of two of the most common types of cancer - breast and prostate - and could also be responsible for developmental problems, testosterone reduction, infertility in certain types of carriers, and even obesity through fat cell stimulation.

BPA particle-to-content migration seems to occur in higher quantities when contents are heated in their containers, as millions of parents have been doing for a long time when heating baby milk bottles. As bottle-fed babies tend to be small, BPA absorption results in a higher concentration of chemical compounds than for adults. These findings are contested by the Bisphenol A alliance which cites other research that shows that baby bottles can be heated in boiling water and microwave ovens with no danger and that dishwasher cleaning is equally harmless.

It’s worth mentioning that polycarbonate plastics are used not only in baby bottles, but also in water cooler bottles and even dental fillings. BPA is also used in the epoxy resin that lines the inside of metal cans.

Detected in humans

BPA worries increased after the Centers for Disease Control and Prevention (CDC) in the U.S. discovered traces in the urine of 95% of adults sampled in 1988 and 1994, and in 93% of children and adults observed in 2003 and 2004. A group of 38 experts established a consensus in July 2007 stating that BPA levels causing adverse effects in animals are lower than what is already in humans. This conclusion was then examined by a scientific panel of the National Institute of Environmental Heath Sciences in the U.S. and found to be sufficiently documented to cause concern.

Beyond relative levels of concentration in human biological tissue, the main concern regarding BPA is its possible role - even at low doses - in the higher incidence of the aforementioned illnesses.

What to take away from all this? A wide consensus has classified food containers, bottles and tableware as almost if not quite completely harmless. However, there are real reasons to be concerned about the use of baby bottles made from polycarbonates, so like with anything in life, let’s not over-reacted, but proceed with caution!
 

See also:

How to limit your exposure to BPA

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