EMA's HMPC (Committee on Herbal Medicinal Products) published the final version of the reflection paper on microbiological aspects of (traditional) herbal medicinal products on 4 June 2015.
Being of natural origin, herbal substances generally have higher contents of micro-organisms when compared to chemically defined drug substances. This presents particular challenges as the micro-organisms may be carried over to the herbal preparation and herbal medicinal product. In addition, spores and toxic mycotoxins generated by the micro-organisms may also be present. These are more difficult to eliminate, once they are present in the herbal material.
Therefore, attention should be paid to the quality of herbal medicinal products with respect to microbiological and mycotoxin contamination during the entire production process - from the beginning.
This reflection paper addresses many critical points that have to be taken into account. They comprise a number of different methods of decontamination that can be used and which are discussed in this document. As a matter of principle preventive methods should be preferred rather than interventions for decreasing the existent contamination.
For more detailed information please see the complete "Reflection paper on microbiological aspects of herbal medicinal products and traditional herbal medicinal products".