Ethylene oxide: toxicology review and field study results of hospital use

Ethylene oxide (ETO) is used extensively within health care facilities for sterilization of equipment and supplies. Alternative chemicals or processes have, in themselves, serious limitations or health hazards. NIOSH recognizes, therefore, that the continued use of ETO as a gaseous sterilant is highly desirable in many situations. Recent results of tests for mutagenesis have increased the concern for potential health havards associated with exposure to ETO. In order to assess the potential for exposure and associated hazards, NIOSH prepared a "Special Occupational Hazard Review with Control Recommendations for the Use of ETO as a Sterilant in Medical Facilities," DHEW (NIOSH) Publication No. 77-200 (Aug. 1977). An assessment was made of the evidence for toxic effects of ETO, especially with respect to mutagenic, teratogenic, and carcinogenic potentials. Additionally, a limited field survey was conducted by NIOSH to document the use, problems, and potential for human exposure in medical facilities. Based on this review, measures for control of control of occupational exposure have been recommended. The report includes a summary of the airborne ETO concentrations measured within health care facilities as part of the field survery. NIOSH estimates that there are in excess of ten thousand ETO sterilizers in use in U.S. health care facilities, and that approximately 75 thousand workers are potentially exposed to ETO in those facilities. Reasons for the unnecessary exposure of personnel were found to include: improper or inadequate ventilation of sterilizers, aerators, and working spaces; improper handling and/or storage of sterilized items; untrained workers operating some sterilization equipment; improper operating techniques leading to mishandling of some ETO sterilizing equipment; poor design of the sterilization facility; and design limitations of the sterilization equipment.