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I received a water bottle for Christmas, but I cannot determine if it contains this material. Nothing on the bottle itself lists what it is made of.

Anyone know how to tell?

Isn't there a triangular recycle logo molded into the bottom?

Take a Q-Tip, dip it in acetone (Fingernail polish will work) and rub it on the bottle. If a thin film softens and glues cotton lint to the bottle, it could be Lexan (Polycarbonate). This plastic is used in cheap drugstore reading glasses, and since I often work with acetone, it is quite a nuisance to see tiny droplets making fisheyes on the lenses when I leave them on the bench and get clumsy.

There are other plastics like the butyrates that acetone will dissolve, but they are not used in food packaging.

Polycarbonate/urethane copolymers have been FDA aproved for use in some implants, and Lexan has been used in disposable labware such as Petri dishes for decades. I really would not worry about it, myself.

People who run injection molding machines are exposed to the fumes from the hot plastics. Since Lexan has been used for decades, if there were serious hazards, they would have shown up among these people, who would have had bisphenol A exposures many times that of the general population.

Here are the doses required to cause death in 50% of a test population:

http://ptcl.chem.ox.ac.uk/MSDS/BI/bisphenol_A.html

ORL means oral dose, MAM is an unspecified mammal, probably a rabbit. RAT is a rat, MUS is a mouse, IPR means intraperitoneal dose (inside the stomach lining).

The dosages are in milligrams, so 6500 mg PER KILO will cause death in a mammal...that is 6.5 grams you would have to eat! Toxicology Toxicity data

ORL-MAM LD50 6500 mg kg-1

ORL-RAT LD50 3250 mg kg-1

ORL-MUS LD50 2400 mg kg-1

IPR-MUS LD50 150 mg kg-1

ORL-RBT LD50 2230 mg kg-1

ORL-GPG LD50 4000 mg kg-1

From what I've read and been told the Polycarbonate materials we use every day are perfectly safe to use. IF you microwave your food or drink in these, day after day after day, then you MIGHT leach out a mg or two in about a year...you'll breath in more carcinogens by walking down the street...

....and since I often work with acetone, it is quite a nuisance to see tiny droplets making fisheyes on the lenses when I leave them on the bench and get clumsy.

Happened to me yesterday.......

Polycarbonate is some mighty tough stuff, though. I have a length of 1" tube made from polycarbonate that I used a piece of to make a fuel sight glass for the airplane I built. You can drive an 8d nail with that tube and it barely makes a scratch on it.....