Introduction: Low surface contamination levels of hazardous drugs in compounding areas can be used as indicators of exposure and efficacy of cleaning procedures. We report the efficacy results of the KIRO® Oncology self-cleaning automated compounding system for decontamination of cytotoxic drugs, assessed in an oncology health center using a sanitizing method and an alkaline method. Methods: The study was conducted for six-days over a three-week period. A mixture with known levels of 5-fluorouracil, ifosfamide, cyclophosphamide, gemcitabine, etoposide, methotrexate, paclitaxel, docetaxel and carboplatin was added to the KIRO® Oncology's compounding area surface before each self-cleaning method was used. Contamination levels were determined, with a surface wipe sampling kit, at the end of the self-cleaning process. Results: Background surface contamination for quantified levels of cytotoxic drugs during routine use of KIRO® Oncology was below limit of quantification (99.8% for all cytotoxic drugs analyzed. Conclusion: This study provides evidence on the efficacy of the KIRO® Oncology automatic self-cleaning system for surface area decontamination during the preparation of cytotoxic drugs. [ABSTRACT FROM AUTHOR]