Monday, November 1, 2010

Bisphenol A

I’ve only recently come across the official name for this organic compound which is used in the manufacture of polycarbonate plastics and epoxy resins. What does this have to do with food? Well, the foods we buy come packaged in plastic; we store food in plastic in the fridge; we may even use plastic containers in the microwave to cook or re-heat foods. Our babies’ feeding bottles, cups, dishes and spoons are made of plastic. And the lining inside aluminium food and drink cans is made from plastic.

Bisphenol A (often abbreviated to BPA) has been known to be estrogenic since the 1930s, and the safety of use of this kind of xeno-estrogen has been in question since 2008. This year, as recently as September, Canada (the only country so far, I think) declared the substance toxic. If you want to be scared witless you can go here to read all about the health implications (and there are plenty of other negative reports – just Google ‘bpa’). At our present level of exposure, it’s amazing that we are all still alive and producing offspring! Then again, you can go here for comfort. Who should we believe? I think we just need to be sensible, be aware and exercise caution.

There are seven classes of plastics used in packaging. Look at the base of your plastic containers – there should be a little embossed triangle made up of arrows. This is the ‘recycle’ symbol, and the number in the middle gives some indication of the formulation of the product. The number will range between 1 and 7. Types 1 and 2 probably contain no BPA. Type 3 – particularly if it’s a flexible or soft plastic - may contain some BPA. Types 4 and 5 appear to be ‘clean’, and Type 6 (polystyrene) contains no BPA nor will it break down into BPA. Type 7 – especially polycarbonates, which may display PC near the recycling symbol - seems to be the ‘bad apple’. Type 7 is applied to all plastics which don't belong to any of the other types.
I’ve just checked my cupboards and most of the boxes are type 2, 4 or 5; most of the bottles are type 1 or 2. My plastic bags say they are type 4. But not everything is marked… sometimes the marking appears on the wrapper (which you probably threw away ages ago). I was surprised to find that my Tupperware boxes were unmarked, yet the Addis boxes are.

One would hope that large, reputable companies – such as Tupperware and Avent – are producing plastic containers which are safe for continued consumer use... Mmmm... better check them out.


Helen said...

I would imagine that your Tupperware (like mine) is too old to have these markings, ALL of my Tupperware dates back to the late 80's - definately not so much consumer awareness back then!!

Patrick Holford has written a great deal about the estrogens in soft plastics - you will probably never put cling film in the microwave EVER again!

Sphinx said...

Hi, Helen,
Join me next Friday (12th Nov) for the low-down on microwaves and what they do to food... maybe you'll never use yours again, never mind the clingfilm!
Thanks for stopping by and taking the time to comment.

Bronwyn said...

France has also made BPA illegal... Remind me to give you that article.

Sphinx said...

Thanks, Bronwyn. I'd like to see that report. xxx