Longitudinal biomonitoring of nurses handling antineoplastic drugs

Aims and objectives.  To assess a possible trend in the genotoxic risk of oncologic nurses during the working year, cytogenetic biomonitoring was performed. Background.  Exposure to cytostatic agents is a major occupational concern in oncologic personnel. In contrast to the controlled environment in oncology pharmacies, nurses may be subject to unexpected events of exposure due to the intensive contact with patients. Design and methods.  The entire nursing staff of an oncology inpatient ward (n = 15) participated in a biomonitoring study over a period of nine months using the sister chromatid exchange test and the comet assay to detect DNA strand breaks. Blood samples were taken after a three-week summer break (base level), one, three, six and nine months thereafter. Airborne contaminations of cytotoxics were addressed by chromatographic methods. Results.  With regard to the single monitoring points, the comet assay revealed no significant alteration of the genotoxic burden within nine months. By contrast, the sister chromatid exchange levels were significantly increased after six and nine months when compared with base levels. A trend analysis covering the whole observation period revealed an increase in genotoxicity as shown by the sister chromatid exchange test and the alkaline but not the neutral comet assay. This increase, however, was small and reversible as shown by the trend analysis of sister chromatid exchange rates during the years of service. Air samples were negative for cytotoxic contaminants. Conclusions and relevance to clinical practice.  The small, but statistically significant genotoxic burden observed in oncologic nurses of an inpatient ward emphasises the need for a continuing effort to eliminate residual occupational risks. In comparison with historical controls, the current situation is characterised by beneficial safety improvements over the last years. Nevertheless, periodic training and awareness of the problems should be an integral part of advanced education.