Sunday, October 7, 2012

Is Plastic Safe to Drink From?

As I talked with a friend of  mine yesterday, he presented me with a question that I am sure a lot of you have also wondered about.  The general question was is it safe to drink from plastic containers, like sippy cups and water bottles.  Good question Jeeves.

The short answer is maybe.

The primary concern comes from a chemical called BPA (or Bisphenol-A).  This chemical is commonly found in hard plastics, and the lining of metal food and drink cans.  BPA can cause neurological and behavioral problems in kids, it is an endocrine disruptor (which means it mimics sex hormones in your body), and can cause reproduction and brain development issues.  95% of people tested were found to have BPA in their systems.

BPA isn't the only harmful chemical in plastic, however concern over potential harm has gotten it the most press.

So how do you know if that plastic sippy cup little Sammy is drinking out of is safe?  Or how about that travel mug full of coffee?  The answer lies largely in the temperature that the plastic is exposed to.

A study done at UC showed that when the plastic is either heated up, or has a boiling liquid put into it, then chemicals are released at a much higher rate.  When examining BPA here is what they found...
However, drastically higher levels of BPA were released once the bottles were briefly exposed to boiling water.
"Compared to the rate of release from the same bottle, the speed of release was 15 to 55 times faster," explains Belcher.
Prior to boiling water exposure, the rate of release from individual bottles ranged from 0.2 to 0.8 nanograms per hour. After exposure, rates increased to 8 to 32 nanograms per hour.  (source- emphasis mine)
For example, plastic water bottles left out in the sun on a loading dock can start to release chemicals into the water, because the water bottle is being heated up.

When studies where done on a nine year old water bottle versus a new plastic water bottle the results showed no difference in release.  The bottles were exposed to cool or temperate temperatures.  So that 9 year old sippy cup your first kid used shouldn't release any more BPA than the brand new one you bought (although hopefully the brand new one is BPA free :).

What it all comes down to is all plastics release chemicals into whatever food or drink is in them.  However a much higher rate of it is released with hot temperatures.  Another concerning example would be when a meal is microwaved in a plastic container, or plastic bag.

There is hope.  We can avoid most, if not all, sources of BPA.  Only hard plastics have BPA in them, however all plastics can leach chemicals into food and drinks.  Plastic that shows the recycling symbol number 7 on it is the kind that has BPA in it. 

There are lots of great stainless steel water bottles available out there, as well as stainless steel thermoses and sippy cups.  For some people glass is a workable option, like glass tuperware and water bottles.  They cost a little more, but should last for a really long time.

For more on BPA and some surprising sources of it, here is an article I wrote about a month or so ago.

Article Sources:
http://www.sciencedaily.com/releases/2008/01/080130092108.htm
http://usatoday30.usatoday.com/news/health/2008-01-29-plastic-chemical_N.htm




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