Application of ozone gas for decontamination of nucleoside anticancer drugs

BACKGROUND Exposure to anticancer drugs is hazardous and may lead to chromosomal abnormalities and spontaneous abortion in healthcare workers. Guidelines recommend surface decontamination and cleaning in order to minimize the occupational exposure to anticancer drugs, although no single process has been found to deactivate all currently available hazardous drugs. Ozone gas is oxidative and a decontaminant for bacteria; its characteristic as a gas has advantages in that it does not need to be wiped off or neutralized after use. METHODS The nucleoside anticancer drugs, cytarabine and fluorouracil, were exposed to ozone gas on plates under controlled humidity. The levels of exposed ozone were evaluated using the concentration-time (CT) value, which is the mathematical product of ozone concentration and exposure time. The effects of exposure to ozone on levels of the anticancer drugs were determined by high-performance liquid chromatography (HPLC). RESULTS The levels of cytarabine decreased with increasing CT value and were not detected beyond 40,000 CT. The decomposition levels of the anticancer drug by ozone were CT-dependent irrespective of the maximum concentration of ozone. Higher humidity in the range from 70 to 90 % accelerated the decomposition of cytarabine and fluorouracil, and neither of the drugs were detected at 90 % humidity after exposure to ozone gas. CONCLUSIONS Ozone gas decomposed these nucleoside anticancer drugs. This is the first report of the applicability of ozone gas as a decontaminator for anticancer drugs.