Bisphenol-A

Bisphenol-A or BPA as it is more commonly known, is used to make polycarbonate polymers and epoxy resins along with other materials used to make plastics.  Over the last ten years, it has been revealed that BPA is highly toxic to humans and may even be carcinogenic.  And although the situation is rapidly changing, many food manufacturers continue to use it in their packaging and so it is important to know which packaging is free of this toxic compound.

Let's take a quick look at some of the scientific findings in relation to BPA and see how we are exposured to it.

Over the last decade, an increasing number of scientific studies have been raising alarm bells about BPA and it's adverse effects on humans. To begin with, early studies revealed that it exerted hormone-like properties and this finding alone raised concerns about its presence in consumer products.

Starting in 2008, several governments questioned its safety, prompting some retailers to withdraw polycarbonate plastic products. A 2010 report from the United States Food and Drug Administration (FDA) raised further concerns regarding exposure of foetuses, infants and young children to BPA products.  

In September 2010, Canada became the first country to declare BPA a toxic substance. In the European Union and Canada, BPA use is now banned in baby bottles.

Several years ago, a panel convened by the U.S. National Institutes of Health determined that there was concern about BPA's effects on foetal and infant brain development and behaviour.  Since then, alarm bells have been sounding about the adverse affects of BPA in many quarters.

Obesity

A 2008 review has concluded that obesity may be increased as a function of BPA exposure because it acts to exert persistent effects on body weight and adiposity.

Nervous System

In the same year, a report by the U.S. National Toxicology Program expressed concern about BPA’s effects on the brain which was later reinforced by the U.S. Food and Drug Administration.

A 2007 review concluded that BPA, like other xenoestrogens, can alter nervous system functions through a variety of pathways.  Numerous animal studies over the last five or so years have added to these concerns and identified BPA’s adverse effects on brain structure.   Basically, the more they study its affects, the more cause for alarm there is.

There are even signs that BPA mimics estrogenic activity and impacts various dopaminergic processes to enhance mesolimbic dopamine activity resulting in hyperactivity, attention deficits, and a heightened sensitivity to drugs of abuse.

Another review that year concluded that Bisphenol-A has been shown to bind to thyroid hormone receptors and perhaps have selective adverse effects on its functions.  

Several studies have now shown that Bisphenol-A is not only toxic but probably carcinogenic, particularly in relation to breast cancer.

BPA studies are now discovering one adverse effect after another, including its suppressive effect on DNA methylation which is linked to epigenetic changes.

Plastic & Canned Foods

As a result of the continuing bad news about BPA, an ever increasing number of people around the world are becoming more discerning about food packaging and storage, baby products and drink bottles.  Pregnant mothers in particular need to avoid BPA products.

For years, many health conscious people long considered polycarbonate to be one of the best non-toxic water containers, second only to stainless steel. Walk through any gym and you'll see this.

Polycarbonate containers are readily recognisable by the recycle number 7 imprinted on them but also because of their hardness unlike the disposable plastic bottles you buy from supermarkets that can easily be squeezed with your fingers.

In general, plastics that are marked with recycle codes 1, 2, 4, 5, and 6 are very unlikely to contain BPA. Some, but not all, plastics that are marked with recycle codes 3 or 7 may be made with BPA.

Now that BPA has appeared on the scene, it turns out that Styrene Acrylonitrile or SAN is BPA free while polycarbonate plastics are not.   Brita, a popular maker of water filter jugs and systems, has even gone to the trouble of stating that their plastics are SAN and BPA free.  Other food manufacturers are also adopting BPA free plastics and making public statements to this effect as word gets out about the dangers of BPA.

The worst BPA culprit of them all may be the inside lining of tinned food and this is yet another reason to stay away from canned foods and always eat fresh, unprocessed food.

What to Avoid

  • Reduce tinned food intake or seek out tins labelled BPA free.
  • Note that some tinned food products are worse than others.  The highest levels of BPA are found in coconut milk, soups, meals (such as pasta dishes), beans, tinned juices and fish.
  • Choose fresh or frozen fruits and vegetables instead of tinnned varieties.
  • Look for products that don't use BPA in their containers; companies that are using alternatives are likely to advertize this on their labels.
  • Check the plastic containers you use at home; although the ID code is voluntary, you should avoid those with the symbol 3 (PVC) or the number 7which is a category that includes BPA.
  • Contact food manufacturers directly and ask them to use alternatives to BPA.

For a list of popular products that are BPA free, visit http://www.bpa-free.com.au/