Effect of plastic

Chemicals May Contaminate Food and Drinks in Reused Plastic Bottles
Studies have indicated that food and drinks stored in such containers—including those ubiquitous clear Nalgene water bottles hanging from just about every hiker’s backpack—can contain trace amount of Bisphenol A (BPA), a synthetic chemical that interferes with the body’s natural hormonal messaging system.

Reused Plastic Bottles Can Leach Toxic Chemicals
The same studies found that repeated re-use of such bottles—which get dinged up through normal wear and tear and while being washed—increases the chance that chemicals will leak out of the tiny cracks and crevices that develop over time. According to the Environment California Research & Policy Center, which reviewed 130 studies on the topic, BPA has been linked to breast and uterine cancer, an increased risk of miscarriage, and decreased testosterone levels.

BPA can also wreak havoc on children’s developing systems. (Parents beware: Most baby bottles and sippy cups are made with plastics containing BPA.) Most experts agree that the amount of BPA that could leach into food and drinks through normal handling is probably very small, but there are concerns about the cumulative effect of small doses.

Even Plastic Water and Soda Bottles Should Not Be Reused
Health advocates also recommend not reusing bottles made from plastic #1 (polyethylene terephthalate, also known as PET or PETE), including most disposable water, soda and juice bottles. According to The Green Guide, such bottles may be safe for one-time use, but re-use should be avoided because studies indicate they may leach DEHP—another probable human carcinogen—when they are in less-than-perfect condition.