[Linny]

The fact is that testing is always one step behind. They cannot test for what they don't know and the chemists are always cooking something up.

Tests are not a matter of taking the sample and seeing what's in it. They test for specific chemicals and reactions indicating the presence or absence of a chemical. By definition, the testing industry is always reactive, not pro-active. Unless tyey have reason to suspect a certain compound is turning up in samples, it wont be found because they wont look for it. They only find what they look for and they only look for what they know.