Can anyone recommend a testing lab to determine the purity of a
[Testing labs are only set up to test amounts of pure substances. Thus, if a supplement is stated to contain several chemicals, each would need to be tested separately (which increases the cost of testing). In addition, not all labs are set up to test all substances. Some substances require more uncommon methods of testing. If the substance is uncommon, they may not have or be able to find the "standard" for it and you may even need to help them out with that. In addition, there is no such thing as general impurity testing. Instead these also have to done for specific substances, so when asking for such testing one needs to supply the names of the particularly impurities about which one is concerned.
For a start one should always consult Consumer Lab to see if the supplement has already been tested by them. If not, then a lab that I have used is American Analytical Chemistry Laboratories Corp - http://aaclabs.com
(ask for Charlie Li). There are many others which can be found by searching, but this is the only one that I have used and can therefore recommend. They can do many kinds of testing on the same substance and some require more that one kind of test to be certain of its identity (eg. sterioisomers). Each such test is priced separately.
Finally, insist that you be sent all raw test results and data so that you can examine them and better understand what has been determined. If you do not specifically request this, then they will only send you a very general summary report of their results. --Paul]
[Dave Saum has fulfilled our identification requirements by virtue of the fact that he uses his name in his email address, has an identifiable photo on his Yahoo ID (since at least 2004) and provides a specific location. We have no reason to believe he is not who he represents himself to be.
Dave, you are welcome to tell us a bit more about yourself, including what mountains you are in and the ruins in the background in that photo. Someplace in the Andes? **Kitty]