Sample loss during measurement of airborne antineoplastic agents

Handling, preparation and administration of antineoplastic drugs are suspected health hazards for hospital and clinic personnel. Measurement of personal and area exposures to such materials in air is difficult because the average concentration is often close to the analytical detection limit. For this reason, and because of the random nature of drug spills and releases, the sampling method of choice typically extends over a 40-hour workweek. In this study a method for monitoring two airborne antineoplastic drugs, fluorouracil and methotrexate, was tested for possible loss of the drug from filters during air sampling. Glass-fiber filters (37 mm) were spiked with known amounts of drug and subjected to the same airflow conditions as are used in workplace sampling. Filter extracts were analyzed using high performance liquid chromatography (HPLC). Losses during storage up to a month were less than 5% for both drugs. Losses during airflow were directly proportional to cumulative air volume, 2% of the amount on the spiked filter/m3 air for fluorouracil and 6%/m3 for methotrexate. Losses during actual collection will be less and ordinarily are not expected to constitute a major hindrance to extended sampling in occupational settings.