Not so fantastic plastics

As discussed in the previous post, chemicals from plastic containers and wrappers may not be as safe as industry and regulators would like us to believe.  Polycarbonate can release BPA, and compounds such as phthalates are added to PVC to make it softer and less rigid.  The main concern surrounding these compounds is the way they have been shown to be endocrine disruptors.  That is, they mimic and disturb our body's hormones. 

Some plastic containers are more dangerous than others.  If you are concerned, and would like to minimise your exposure, use the table below to see which ones are best avoided.

The table is taken from a fantastic article on Choice online, and can be found here.

You can often identify the type of plastic from its identification code – unfortunately, this code is voluntary and you won’t find it on all plastic packaging. Look for the codes 1 (PET), 2 (HDPE), 4 (LDPE), 5 (PP) and 6 (PS). Whenever possible avoid foods or beverages that have been in contact with plastics with the symbol 3 (PVC) or 7 (a catch-all category that includes polycarbonate).

Many packaged foods are in plastic containers that seem to be harmless.  Soft drinks and bottled water are usually in PET bottles, for example, while yoghurt and margarine containers are usually made from polypropylene. There’s clearly no real need for food manufacturers to use packaging or wrapping made from polycarbonate or PVC, but there are still far too many products in the supermarkets where the food is in contact with these potentially harmful plastics.

Plastics - Harmful to our health?

It may surprise you to learn that the most prevalent exposure to environmental pollutants is in the house (providing the workplace is not a problem).   One of our biggest exposures is to plastic, and there is growing evidence that our food and drink can be contaminated by harmful chemicals from some types of plastic.  It is the daily cumulative exposure that is the problem.

Photo by Kangshutters

Many plastics contain plasticisers which are used to make hard plastics soft.  Phthalates, such as the well known BPA (Bisphenol A) have a small molecular structure and can be readily absorbed  - meaning they can be transmitted into food and digested, or absorbed through the skin.  All plastics have phthalates in them, BPA is just deemed more dangerous.

Plastics are a problem in our bodies because they are endocrine disruptors, meaning they can mimic our natural hormones, our reproductive hormones in particular.  The young are the most vulnerable to exposure because of their lower body weight and because their growth and development are strongly influenced by hormones.  
 
While these compounds are undoubtedly hazardous at high levels of exposure, scientific opinion is divided over the risk from the much lower levels that we’re exposed to every day in our food. There is, however, growing scientific evidence that even at these lower levels of exposure, phthalates and BPA may be causing problems such as infertility, obesity, breast cancer, prostate cancer, heart disease and diabetes.

Photo by Stoonn

It is scary stuff, but there are things you can do to minimise your exposure to these chemicals:

• Don't heat food in plastic containers
• Don't store oil based or acidic food (such as tomatoes) in plastic
• Avoid fresh meat, fruit or vegetables wrapped in cling wrap, as many supermarkets and greengrocers are still using cling wrap containing PVC.
• Don't repeatedly wash plastic containers in the dishwasher

Remember, it is the cumulative exposure that is the problem.  If we can decrease our exposure wherever possible, the occasional contact with plastic is less likely to be a problem.