Water Bottle Plastics /h3>

Name: Jesse
Status: student
Grade: 4-5
Location: NY

Question: Is refilling a bottle of water hazardous because of the
decomposing plastic?
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There were some reports several years ago cautioning people not to re-use
most disposable water bottles because of the plastic degrading and leaching
chemicals into the water.  Do a web search for this---certain plastics are
thought to be OK for this purpose.  I think Nalgene brand may be one of the
"safer" ones.

Patricia Rowe
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Jovelyn,
 
Studies have shown that in order for a ship to be able to create a vortex 
(a rotating funnel) or a partial vacuum that would have to be strong enough 
to drag down a person (or indeed most anything), the ship would have to be 
quite massive and to sink very fast. This is simply not the case. Ships sink 
because water goes into the ship and its buoyancy is negated. Water can not 
flow into a ship fast enough to make the ship sink fast enough to create the 
kind of partial vacuum that can suck in anything like a person.
 
Greg (Roberto Gregorius)
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I want to discuss three possible issues: 1) breakdown of plastic, 2)
leeching of materials from the plastic, and 3) microbial growth.

The breakdown of plastic is probably not hazardous. Most bottles are made
from PET (polyethylene terephthalate), (for example Dasani and many other
water bottles are made from PET), although you can find bottles made of
other materials as well. In general, these polymers don't breakdown readily
unless they're treated with heat or a catalyst or something else to
accelerate their breakdown. I would say this should not be a big source of
concern to you.

Some polymers have additives in them that can leech out of the plastic. Some
of those additives may be harmful in certain circumstances. However, I'm not
aware of issues with PET water bottles like those that are being
investigated with other materials. I would say that leeching of chemicals
from the PET plastic bottles into your drinking water is likely not a high
risk.

The third issue is the one I want to emphasize. Re-using water bottles
without cleaning them adequately can allow bacteria to grow, even more so
with 'vitamin' waters that have sugar added. Even plain old water can
support microbial growth. Reusing without adequate cleaning can allow
bacteria or fungi to grow to levels that could be harmful. If you re-use
bottles, consider using ones that are easy to clean (or even are dishwasher
safe). If you insist on reusing PET bottles, be sure to clean them
thoroughly with soap and hot water and rinse and dry them.

Another good option is tap water in a well-cleaned bottle. Tap water is
nearly always equally pure, equally safe, and much cheaper.

Hope this helps,
Burr
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No, it is not.  It is a stretch to say that refilling a bottle is
dangerous. The bottled water industry wants you to think that it is,
because refilling a bottle means that they won't sell as many bottles.
Their basis for saying that refilling is dangerous is not because of any
problem with the plastic, but because bacteria grow in dirty bottles.
If you regularly wash the bottles, however (though it is hard to find a
bottle brush nowadays!), there is no cause for concern.

Richard Barrans, Ph.D., M.Ed.
Department of Physics and Astronomy
University of Wyoming
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This is a rather contentious issue. The leaching of various components
of the plastic is tricky to assess because the "history" of the bottles are
not the same -- old vs. new, washed in hot water vs. stored in a
refrigerator or freezer, ..., the list is long. A more immediate risk is the
contamination of the water from microbes in the previous user's mouth, even
one's own. Plastic bottles for off the shelf bottled water are not designed
for multiple re-use. For a variety of both health and environmental reasons,
why not use glass?

Vince Calder
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