Use of micronucleus assays to measure DNA damage caused by cytostatic/antineoplastic drugs

Occupational exposure to antineoplastic drugs (ANPD) raises concerns regarding possible health effects on healthcare workers. In fact, even when healthcare workers are specifically trained and ANPD handling occurs according to issued guidelines and/or safety recommendations, accidental contamination in the workplace (and a concurrent increased exposure risk to genotoxic/carcinogenic compounds, such as chlorambucil, cyclophosphamide, etoposide, etc.) is still detectable. Cytogenetic biomarkers are the most frequently used endpoints in human biomonitoring studies to assess the impact on health of environmental/occupational exposure to genotoxic xenobiotics. Among the cytogenetic assays, the lymphocyte cytokinesis-block micronucleus (L-CBMN) assay is one of the most frequently used and, to date, the best validated method for biological effect monitoring in subjects occupationally exposed to genotoxic xenobiotics. The assessment of micronuclei (MN) in uncultured, exfoliated epithelial cells from oral mucosa (B-MN assay) has provided a complementary method for cytogenetic analyses in easily accessible tissue without cell culture requirement. Using PubMed and an appropriate combination of key words, we retrieved 28 studies, published from 1988 to 2018, measuring MN in healthcare workers occupationally exposed to ANPD. The overall evaluation of the currently available studies clearly shows a significantly increased genotoxic risk for healthcare workers occupationally exposed to ANPD.