Validation protocol and analytical quality in biological monitoring of occupational exposure to antineoplastic drugs

Occupational exposure to antineoplastic cytostatic drugs has been recognized as a potential health hazard since the seventies. Safety guidelines and recommendations have been published in several countries in order to improve operating procedures and keep exposure levels as low as possible. Nevertheless, contamination still occurs. With a view to preventing exposure, standardized authorized methods and a mandatory monitoring system appear to be an essential prerequisite. First of all, reliable analytical methods are necessary, and a wide number of drugs should be monitored, on the basis of the continual change in the treatment protocols. In fact, most of the methods available in the literature were not properly validated, and a lack of details concerning quality assurance is clearly observed. When assessing analytical methods applied for routine testing, validation studies are of utmost importance. Not only performance parameters, such as sensitivity, specificity, LOD and LLQ, should therefore be determined, but also the uncertainty of measurement, which gives a measure of the confidence that can be placed on the results.