Tuesday, 1 June 2010

Plastic Not Fantastic

You may remember back in January that I wrote about the advice I had been given to try to avoid soft plastics coming into contact with my food and drinks.

It’s a tall order. Just scan the shelves of your local supermarket... I got to wondering what we did before plastic packaging took over the world?

In Sydney, Sam the Butcher’s in Bondi Road willingly agreed to wrap my meat in greaseproof paper, rather than the ubiquitous soft plastic sheets. I was pleasantly surprised by their progressive attitude. I generally view butchers as a Luddite lot. The other day I went into my local butchers (name withheld) on Portobello Road and made the same request. The flesh-hacker on duty practically laughed me out of his shop. “We won’t do that,” he roared, “it’s too expensive. Anyway if we listened to all that rubbish where would we be?” “Healthy and possibly cancer-free?” I muttered. “Oh, I know all about that,” he replied, “my mum died of cancer. My aunty too.” Well that makes sense then.

But trying to avoid all soft plastics in contact with my food is only serving to make me feel fearful and utterly defeated. It’s an unachievable goal. And why do we want to do it anyway? I started reading up a bit more.

Here is what I have learned: There are lots of different types of plastics. Contrary to what I previously believed, if I ever thought about the subject at all, plastics are not necessarily inert. Many plastics leach various chemicals in varying amounts. The chemicals can then be absorbed into our food. Many of these chemicals are toxic and cumulative in the body. Apparently the two main baddies (but not the only ones) are Bisphenol-A (BPA) and Phthalates*. Both act as endocrine disruptors, i.e. they mimic hormones in the body.

The uptake is greater if the food has a high fat content, for example: cheese, meat, bacon, pastry, oily fish and the like. In general, plastic will release far more chemicals when heated. The white lining of tins is made of plastic and known to leach Bisphenol-A. I read that tins are heated to high temperatures when they are sealed. I picture the food inside the tin being bathed in a hot soup of BPA molecules.

Lucky for us, manufacturers are now required to categorise all plastics, for recycling purposes. If you get your magnifying glass out and search you will somewhere find a small triangle made up of three swirling arrows, with a number in the middle. This number indicates what type of plastic it is. I have copied this from the Smart Plastics Guide:

1          POLYETHYLENE TEREPHTHALATE (PET)          No known health issues
2          HIGH DENSITY POLYETHYLENE (HDPE)            No known health issues
3          POLYVINYL CHLORIDE (PVC OR V)                   Many harmful chemicals are produced in the manufacturing, disposal, or destruction of PVC including: • Lead • DEHA (di(2ethylhexyl)adipate) • Dioxins • Ethylene dichloride • Vinyl chloride. Effects of exposure to these chemicals may include: decreased birth weight, learning and behavioral problems in children, suppressed immune function and disruption of hormones in the body, cancer and birth defects, genetic changes.
4          LOW DENSITY POLYETHELENE (LDPE)             No known health issues
5          POLYPROPYLENE (PP)                                      No known health issues
6          POLYSTYRENE (PS)                                           Styrene can leach from polystyrene. Over the long term, this can act as a neurotoxin. Studies on animals report harmful effects of styrene on red-blood cells, the liver, kidney, and stomach organs.

This is where it gets tricky...

7          MIXED (OTHER)                                                  Health effects vary depending on the resin and plasticizers in this plastic that often includes polycarbonates. Polycarbonate plastic leaches bisphenol A (BPA) a known endocrine disruptor. By mimicking the action of the hormone, estrogen, bisphenol A has been found to: effect the development of young animals; play a role in certain types of cancer; create genetic damage and behavioral changes in a variety of species. Bisphenol A is widespread--one study found BPA in 95% of American adults sampled.

So, not all plastics marked number 7 contain BPA, some of them are quite safe. Here is what an organisation called the Institute for Agriculture and Trade Policy has to say on the matter: 

Confused about #7 plastic? You’re not alone. Just a few years ago, most #7 plastic was polycarbonate, a plastic we should avoid. Now many new plastics also fit into the #7 category. If it’s labeled # 7-PC, it’s unsafe polycarbonate. (NOTE: not all polycarbonate plastics have the PC label.) If it’s labeled “PLA” or “compostable,” it’s a safer, bio-based plastic. Otherwise, you will need to call the manufacturer and ask them what type of plastic it is.

There is also a whole new generation of plastic-like packaging materials coming into use, made from things like corn starch. I truly hope that these prove to be safer alternatives.

Annoyingly, phthalates are also present in a wide range of skin care products and cosmetics.


Sally said...

Yes, I just stocked up with cans of ORGANIC tomatoes, on special at my local health/wholefood shop and have found that they're all lined with white plastic. Bugger!