Program to monitor surface contamination by methotrexate in a hematology-oncology satellite pharmacy

Purpose. The results of contamination monitoring during a one-year pilot period are described. Summary. A hematology-oncology satellite pharmacy conducted contamination monitoring for one year, using methotrexate as the index marker. From January 12, 2005, to December 21, 2005, 40 sampling sessions occurred during which 238 wipe samples (excluding positive controls) were collected. Each week, seven wipe samples were prepared by pharmacy technicians. Samples were obtained from the blank reference (site 0), the external metallic window frame of the main biological safety cabinet (BSC) (site 1), the back of the phone receiver (site 2), the external surface of an i.v. solution bag that was inside the BSC the previous hour (site 3), a working surface used for the final packaging and labeling (site 4), and the floor of the preparation room (site 5). The sixth sample was a positive methotrexate control. The methotrexate was detected by a high-performance liquid chromatograph with a fluorometric detector. Five samples tested positive for methotrexate-two from site 1, one from site 2, one from site 4, and one from site 0 (the blank); the last finding was thought to have most likely been the result of an error or sample mix-up during the wipe-sampling procedures. Despite differences in the sampling methods used, the type of wetting solution used, and the volume of desorption solution, the results were consistent with the literature in terms of few positive results. Conclusion. A program was developed to monitor surface contamination by methotrexate in a hematology-oncology satellite pharmacy.