Water Bottles 101: Perplexing Plastic Puzzle

Test your water bottle knowledge with this quiz that may have you second guessing your hydration habits.


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Reusable water bottles are standard for hydration-conscious guzzlers, yet ironically they’re fraught with health concerns. Take this quiz to see how bottle savvy you are.

1. What’s to worry with reusable water bottles?
a) They may alter the taste of the water.
b) They may harbor bacteria.
c) They may leach harmful chemicals into the water you drink.
d) Both b and c

2. Which two health problems have reusable polycarbonate bottles (Lexan) been linked to?
a) pregnancy abnormalities in mice
b) stomach upset
c) hormone-related problems

3. How should a reusable plastic water bottle be cared for?
a) Keep refilling it.
b) Run it through the dishwasher after every use.
c) Wash it by hand after every use.

4. When is it time to throw out a plastic reusable water bottle?
a) When it breaks.
b) Never. Bottles usually get lost before they need to be disposed of.
c) When the plastic appears cloudy, cracked, or etched.
d) When the water tastes funny.

5. What’s the best water container?
a) a Thermos
b) a plastic water bottle
c) a goat bladder
d) a metal canteen


1. d) When water bottles aren’t properly washed, health-threatening bacteria grow. Also, scientists are investigating whether reusable plastic bottles, especially those made of polycarbonate plastics such as Lexan (labeled #7 on the bottom), may leach harmful chemicals into water. (The popular clear, sturdy bottles, including the Nalgene brand, are made of Lexan.) In addition, PVC containers are a leaching hazard.

2. a) and c) Researchers at Case Western Reserve University found that mice had higher rates of “chromosomally abnormal pregnancies” when exposed to bisphenol-A (BPA), a synthetic substance in polycarbonate plastics that mimics hormone action. Though BPA isn’t conclusively linked to the same problems in humans, it’s cause for alarm—even though it’s approved by the U.S. Food and Drug Administration.

3. c) Hand wash. Dishwasher detergents and heat may speed plastic’s breakdown and hasten release of BPA. However, not washing the bottle is unhygienic, so hand wash the bottle with mild soap. Also, don’t let water sit in a bottle; empty it after every use and air dry to minimize bacteria growth.

4. c) The less-than-pristine look indicates the plastic is breaking down and could be leaching chemicals.

5. You decide. A Thermos’s glass lining is leach free, but it’s bulky and heavy. Metal canteens impart unwanted flavor, and stainless steel can release minute amounts of nickel. That leaves lightweight, unbreakable plastic. Unfortunately, one-time-use plastic containers are a huge source of landfill waste. If you’re at home or in the office, the best choice might be a washable pitcher and glass.