Studies of the origins and control of occupational exposure to cytotoxic drugs

  • Sarah Roberts

Student thesis: Doctoral ThesisPhD


A three-part project was devised to investigate the origins of and potential methods to reduce the risk of occupational exposure to cytotoxic drugs. The first phase involved researching the current decontamination methods applied in UK hospital pharmacies, which manipulate cytotoxic drugs. The second phase evaluated practical decontamination methods, and the third phase investigated one intervention aimed at reducing or preventing contamination occurring in an isolator. A questionnaire was sent out to ASU managers in NHS hospital pharmacies to gain information about the disinfection and decontamination procedures and products used. The practical decontamination methods investigated were mechanical removal and degradation by detergents (pH range from 1.7 - 13.2) and cleaning agents, and degradation by vaporised hydrogen peroxide. Analytical methods were developed and validated to recover and quantify the amount of cytotoxic marker drug remaining after the decontamination tests carried out in phase two, and to recover and quantify cytotoxic surface contamination from various surfaces in phase three of this work. This composed an attempt to evaluate the effectiveness of a closed-system e.g. PhaSeal® device for fluid-transfer, in reducing contamination produced from the compounding of cytotoxic drugs in an isolator. The detergents and cleaning agents were effective in removing or reducing cytotoxic surface contamination. Alkaline detergents caused degradation of doxorubicin (maximum 81% at pH 13.2 after 1 hour exposure); the other detergents tested did not xi x degrade the cytotoxic drugs investigated. Exposure to vaporised hydrogen peroxide (1.6g min-1 for 2 hours) caused the degradation of cyclophosphamide (98.9%), 5-Fluorouracil (29.3%), doxorubicin (71.0%) and epirubicin (65.9%) when exposed in pharmaceutical diluents. The closed-system (PhaSeal®) device was effective in reducing contamination produced in an isolator from the compounding of cytotoxic drugs. The risk posed by handling and manipulation of cytotoxic drugs and products to the operator and the environment may be reduced, if not eliminated by considering additional approaches to the methods already in place. Firstly, the application of effective decontamination methods; and secondly, by using an effective closed-system, for example the PhaSeal® drug transfer device in a controlled environment.
Date of Award1 Feb 2008
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorGraham Sewell (Supervisor) & Michael Threadgill (Supervisor)


  • exposure
  • cytotoxic drugs
  • contamination

Cite this