Chemicals in Plastics

By Bonnie Jenkins, Advanced Natural Medicine

A few months ago, I told you how one of the chemicals in plastic – bisphenol A (BPA) – can migrate into the foods you eat. But now, according to the Centers for Disease Control and Prevention (CDC), it looks like some of that plastic is overwhelming our bodies!

During the recent study, the CDC measured the amount of BPA in the urine of more than 2,100 people between the ages of 6 and 85. Shockingly, the agency found detectable levels of BPA in nearly 95 percent of those tested, despite the fact that our bodies metabolize this chemical within a few days. And, at the levels the CDC found, it means that BPA is biologically active in the body.

Plastic, Plastic Everywhere

It’s hard to imagine a world without plastics – it’s in everything from cell phones and CDs to cosmetics and shower curtains. We are constantly in contact with it. But the majority of what’s in our bodies comes from foods and beverages that come into contact with plastic. Little wonder – after all, we buy, store, prepare, cook, wrap and serve much of our food with this seemingly indispensable man-made substance.

To be fair, plastics have never been proven harmful to humans. Of course, that may only be because no one has bothered to look. But, while there haven’t been any clinical trials done on plastics biological impact on people, research on animals combined with environmental observations of sea life and wildlife suggest that plastic can have some nasty affects on living creatures – including us! Some experts say that ingesting even small amounts of plastics over a long period of time could lead to increased rates of cancer, neurological and metabolic disorders, reproductive problems and a host of other ailments.

Hitting the Bottle

Even though scientists have debated the safety of plastics for decades, fears escalated recently when a report released by the National Toxicology Program expressed concern over widespread low-level exposure to BPA. At the same time, Canada issued a ban on BPA in baby bottles, designating it a "dangerous substance" and taking steps to limit its use for all consumers.

BPA is the key chemical in the polycarbonate resin used to manufacture the plastic found in clear, hard plastic reusable water bottles, some baby bottles and some food containers. It’s also the main ingredient in epoxy resins used to line cans of food, pizza boxes and water pipes.

The problem is, researchers have discovered that BPA mimics estrogen in the body and can disrupt the way our hormones work. Because of this, there is a growing suspicion that BPA promotes prostate and breast cancers, the early onset of puberty, plus developmental and behavioral problems.

I had always known that estrogen impacted a number of body functions, but to get the details I called Scott Belcher, Ph.D., a BPA researcher at the University of Cincinnati. While he admitted that no one really knows exactly what BPA does in humans, estrogen has wide-ranging effects in the body. In addition to the reproductive system, Dr. Belcher told me that estrogen is involved in the brain, the heart, the immune system, even bone density.

BPA may even be involved in weight gain and obesity. According to Retha Newbold, Ph.D., biologist at the National Institute of Environmental Health Sciences, "Rats exposed to BPA before birth or when very young are more likely to become obese later on in life than those not exposed." New research from Spain points to the pancreas, suggesting that BPA may disrupt insulin release and glucose metabolism, potentially leading to weight gain and metabolic syndrome.

In one recent study, Dr. Belcher tested how much BPA seeped into water (at room temperature) from polycarbonate clear, hard plastic bottles, like those used by hikers. Not only did all of the water test positive for BPA, but the levels were the same whether the bottles were new or used. What’s more, when the bottles were filled with hot water and then cooled overnight (similar to making hot brewed ice tea), BPA levels were 55 times greater.

But heating isn’t the only thing that increases the release of BPA. Dishwasher detergents can also speed up the process, so putting plasticware in the dishwasher might not be a good idea, even if it says "dishwasher safe" and even if you place it on the top rack. Highly acidic foods like tomatoes or citrus may increase BPA leaching as well.

It's a Wrap

BPA isn’t the only plastic that worries scientists. Polyvinyl chloride (PVC) and polystyrene (think white clamshell take-out containers) are other problem plastics when they contain chemical "plasticizers." Plasticizers are compounds that make hard PVC flexible. It’s also what gives plastic wraps their stretch and clinginess. The most notorious of these is diethylhexyladipate (DEHA).

Commonly used in deli wraps, DEHA migrates into foods that are high in fat, like cheese and hamburgers, as well as hot foods that come into contact with it. Like BPA, DEHA is linked to hormonal abnormalities and has estrogen-like properties. So which wraps contain DEHA? It’s easier to know which ones do not. "Safe" wraps include Saran Wrap and Glad Wrap. But just to be on the safe side – I don’t think you should use any type of plastic wrap in the microwave.

One Last Thing ...

While it’s pretty much impossible to go plastic-free in today’s world, it is possible to make better choices and cut back on your usage. Polyethylene terephthalate (PET or PETE) and high-density polyethylene (HDPE) – #1 and #2 in recycling lingo – are two of your better bets, from both a recycling standpoint and a personal health standpoint.

As for the current plastics controversy, even if you can’t go BPA-free, reducing your exposure just a little may make a difference. In the meantime, don’t underestimate your power as a consumer. The more that customers demand plastics without harmful substances, the more manufacturers will listen.

This Just In ...

It seems like every other week there is a new study on some exotic dietary supplement promising to boost brain power. But sometimes it’s good to just go with the tried and true basics. That’s just what Canadian researchers did recently when they decided to test the power of vitamins C and E.

The Canadian team studied 16 men and women with type 2 diabetes, assigning them to one of three meals on three separate occasions: a high-fat meal, the same high-fat meal supplemented with 1,000 mg. of vitamins C and 800 IU of vitamin E, or water alone. After the meals, they took a series of neuropsychological tests to measure their recall abilities. As expected, the high-fat meal worsened recall in the participants, but this memory-dampening effect was offset by the high-dose antioxidant vitamins. This was especially significant because type 2 diabetes causes oxidative stress in the body.

Even if you don’t suffer from diabetes, taking high doses of these two antioxidants can quash the production of the memory-damaging free radicals triggered by high-fat meals. Best of all, taking vitamins C and E daily may help prevent the memory impairment that can happen to all of us as we get older.

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References:

Calafat AM, Ye X, Wong LY, et al. “Exposure of the U.S. population to bisphenol A and 4-tertiary-octylphenol: 2003-2004.” Environmental Health Perspectives. 2008; 116:39-44.

Chui MH, Greenwood CE. “Antioxidant vitamins reduce acute meal-induced memory deficits in adults with type 2 diabetes.” Nutrition Research. 2008; 28:423-494.

Le HH, Carlson EM, Chua JP, et al. “Bisphenol A is released from polycarbonate drinking bottles and mimics the neurotoxic actions of estrogen in developing cerebellar neurons.” Toxicology Letters. 2008;176:149-156.

Miyawaki J, Sakayama K, Kato H, et al. “Perinatal and postnatal exposure to bisphenol a increases adipose tissue mass and serum cholesterol level in mice.” Journal of Atherosclerosis and Thrombosis. 2007;14:245-252.