In the pharmaceutical industry, impurities can arise at numerous points in the various processes used. They could occur during research and development, but also during production of the active substances. In the latter case, it is of paramount importance that the structure of the impurity is clarified so that the triggering fault can be rectified and/or a toxicological evaluation carried out.
This is the only basis on which to assess whether the batch produced can be used, or whether it requires filtration to get it to a usable state. Furthermore, it is important to ascertain whether the impurity originates from the raw material, is process-related or is caused by the replacement of an item in the process.