Considering risks to healthcare workers from glutaraldehyde alternatives in high-level disinfection
Introduction
High-level disinfection (HLD) is a cleaning process that kills all micro-organisms except bacterial spores.1 For the past 40 years, glutaraldehyde (in 2–4% solution with water) has been the primary chemical used for HLD. Glutaraldehyde is highly effective but it has been associated with a number of serious health problems among employees, including dermatitis and occupational asthma.2, 3, 4, 5 In 1999 and 2000, two new high-level disinfectants were introduced to the market: Cidex OPA® [0.55% ortho-phthalaldehyde (OPA) solution] and Compliance™ (0.23% peracetic acid/7.35% hydrogen peroxide). Both were promoted as safer alternatives to glutaraldehyde even though there was little evidence available to support (or refute) such claims. Although substitution of hazardous chemicals is generally considered to be good practice for reducing risk in the workplace, replacing a known hazard with a chemical with largely unknown toxicity may not be a solution. Basic toxicology data may not be sufficient to determine the potential health effects of new chemicals, and unknown problems may surface later. It is easy to assume that a substance is not hazardous just because it is not known to have serious health effects. A lack of knowledge should be taken as a warning rather than an indication of safety.6 This project used the example of HLD to examine issues surrounding chemical substitution and employee health, particularly in the acute-care sector of the healthcare industry.
This paper describes the results of a two-part study involving a survey of current practices relating to high-level disinfectant use in hospitals and a review of toxicity data for a range of high-level disinfectant chemicals. As the survey was exploratory in nature, it was not designed to test any preformed hypotheses. The purpose of the survey was to gather information about which chemicals were being used, where they were being used and the decision processes for choosing high-level disinfectant chemicals. The purpose of the toxicity review was to assess all available health information for existing high-level disinfectant products, with particular attention to newer glutaraldehyde alternatives and their relative sensitization potential.
Section snippets
Survey development and implementation
The survey population included all acute-care hospitals in British Columbia, Canada. A letter explaining the purpose and format of the survey was mailed to the Chief Executive Officers of each Regional Health Board, Community Health Council, Community Health Service Society, and related healthcare unions in British Columbia. A database was created to include the occupational health manager or other personnel responsible for HLD within each hospital.
Product research and key informant interviews
Survey response
The questionnaire was mailed to all 95 acute-care hospitals in British Columbia, and responses were received from 64 (67%). Of these, 51 (80%) were using some form of HLD. Approximately half of the hospitals using high-level disinfectants were using glutaraldehyde alone, while half had introduced alternatives either exclusively or in combination with glutaraldehyde. Where alternatives were in use, OPA solutions were used much more frequently than peracetic acid/hydrogen peroxide solutions (
Discussion
This study suggests that there is a high degree of concern about health among employees who are directly involved in HLD. Despite this concern, there is evidence that the risk management of high-level disinfectants is inadequate. The fact that health was a frequent reason for both introducing and avoiding glutaraldehyde substitutes points to the uncertainty about the potential health effects of these new products. That a high level of concern about employee health was not used as a criterion
Acknowledgements
The authors acknowledge the Canadian Institutes of Health Research, the Occupational Health and Safety Agency for Healthcare, the British Columbia Worker's Compensation Board, the Natural Sciences and Engineering Research Council and the Michael Smith Foundation for Health Research for financial and other support for the project. We would also like to thank the study participants who responded to the questionnaire.
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