25 December 2008

Danger of polycarbonate and plastic bottles

Plastic polycarbonate bottles are still popular as drinking water bottles. (check the no 7 within the triangle at the bottle's base). However polycarbonate releases a chemical known as bisphenol A also know as BPA.(the Canadian government took the stance to officially declare bisphenol A toxic). Whereas plastic industry safety studies find no significant health effects from typical daily doses of bisphenol A, some US government studies found harmful health effects especially to children and expecting moms, but also for male sexuality and reproduction as well.

The problem is that bisphenol A acts as a "xenoestrogen," which just means it's like the female hormone estrogen, except for two things:

1) it's foreign to the body, which is what "xeno" means, and

2) it is way more harmful than our natural estrogen for everyone, male and female.

Breast cancers are much more of a risk in women who carry a high burden of xenoestrogens, and both sexes are subject to a huge range of other harmful health effects. The most far-reaching effects are birth defects and miscarriages. Another effect is a disruption of beta cell function in the pancreas, which creates a pre-diabetes type condition of high blood insulin and insulin resistance.

Never leave a plastic water bottle on a hot car seat, because the phthalates used in the manufacture of plastics leach into the water that you then drink. Phthalates are another xenoestrogen. However, with the polycarbonate bottles it has been found that even at room temperature, bisphenol A leaches into the water, and more so with increased temperature. Also with repeated use of plastics, you may notice the fine line scratches that you see on an old plastic container. These increase the surface area exposed to the liquid inside and release more of the xenoestrogens into the water.

Sure, glass can break. But if you're careful with it, that's not a problem. And considering all the problematic substances in plastics, the breakability of glass does not seem like such a tragedy. Once you get used to carrying it, it is just as easy as polycarbonate bottles.

So next time you order your favourite teh tarik, make sure it is in glass and not in plastic cup.

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