[The purity testing of drugs and drug preparations according to flexible pharmacopoeia instructions].

It is well known, that the quality standards of the various pharmacopoeias are based on certain procedures of synthesis or preparation concerning the drugs. Altering the manufacturing methods or importing these drugs from different producers, it may arise that the examined substance will formally come up to the quality directions of the pharmacopoeia agreed upon, but will contain possible, critical contaminations which are beyond the pharmacopoeia directions of examinations.