Microbiological cross-contamination

Isolation of Processes To minimize cross-contamination and microbiological contamination, the manufacturer may develop special procedures for the isolation of processes. The level of facilities isolation depends on the types of products to be manufactured. For instance, steroids and sulfas require more isolation than over-the-counter (OTC) oral products [6], To minimize exposure of personnel to drug aerosols and loss of product, a sealed pressure vessel must be used to compound aerosol suspensions and emulsions [21], An example of cross-contamination with steroids was the controversial case of a topical drug manufactured for the treatment of skin diseases. Fligh-performance liquid chromatography/ultraviolet and mass spectrometry (FIPLC/UV, FIPLC/MS) techniques were used by the FDA for the detection of clobetasol propionate, a class 1 superpotent steroid, as an undeclared steroid in zinc pyrithione formulations. The product was forbidden and a warning was widely published [22],... 

A good microbiological sterile technique is required to ensure a minimum of cross-contamination with other algae and to prevent the introduction of bacteria. The degradation of the toxicant by introduced bacteria can alter the apparent toxicity even to the point of eliminating the test compound from the media. 

Processing of herbal materials may generate dust or material which is susceptible to pest-infestation or microbiological contamination and cross-contamination. Effective cleaning of the equipment is therefore particularly important. 

The presence of a product of any chemical or microbiological contaminate, which may have the potential to adversely affect the health of any patient or impair the therapeutic activity of the product, is unacceptable. Particular attention should be paid to the problem of cross-contamination, since even if it is of a nature and at a level unlikely to affect health directly, it may be indicative of unsatisfactory manufacturing practices. 

P Rusin, S Maxwell, C Gerba. Quantitative evaluation of bacterial cross-contamination of the hands following everyday activities. American Society for Microbiology Poster Symposium, Los Angeles May 2000. 

In pharmacies a laminar flow unit is used to protect the product against microbiological contamination from the operator. With a cross flow LAF cabinet the HEPA filtered air is directed over the working area to the operator. This type of LAF bench thus cannot be used for operations with hazardous substances (hazardous being defined as any substance with a H statement, so with a hazard class higher than one, see Sect. 26.3.1). It can be used for aseptic preparation processes with closed systems, such as aseptic handling, see Chap. 31. 

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