Chun-Yip Hon

Pilot assessment of the antineoplastic drug contamination levels in British Columbian hospitals pre- and post-cleaning

Objective. We undertook a pilot study involving six British Columbian hospital pharmacies to determine if antineoplastic drug contamination of surfaces exists and whether residual drugs remain on these surfaces despite being cleaned. Methods. At each site, the pharmacy technician responsible for preparing the antineoplastic drugs was observed to determine which surfaces were contacted and to ascertain the frequency of contact. Surfaces observed to be most frequently contacted were subsequently wiped after drug preparation pre- and post-clean. The wipe samples were then analyzed by liquid chromatography tandem mass spectrometry to determine the amount of contamination. Cyclophosphamide (CP) and methotrexate (MTX) were used as representative markers to reflect overall antineoplastic drug contamination levels. Results. Fourteen of the 23 surfaces sampled pre-clean (61%) were contaminated with either MTX or CP. The pre-clean wipe samples had a geometric mean concentration of 0.0135 ng/cm2 for MTX (range <Limit of Detection {LOD} to 12.45 ng/cm2) and 0.114 ng/cm2 for CP (range <LOD to 8.53 ng/cm2). Post-clean contamination levels were generally lower than its pre-clean equivalent; the concentration difference post- vs. pre-clean was statistically significant for CP only. However, some samples appeared to have higher post-clean contamination levels. Conclusions. The results suggest that drug contamination is common in hospital pharmacies we sampled and that current cleaning practices in British Columbia may not be effective in removing residual drug from the surfaces. A more extensive study is recommended to confirm these results as well as a review of cleaning protocols to ensure their effectiveness in reducing contamination levels.

Research gaps in protecting healthcare workers from SARS and other respiratory pathogens: an interdisciplinary, multi-stakeholder, evidence-based approach.

Objective:To identify priorities for further research in protecting healthcare workers (HCWs) from severe acute respiratory syndrome (SARS) and other respiratory pathogens by summarizing the basic science of infectious bioaerosols and the efficacy of facial protective equipment; the organizational, environmental, and individual factors that influence the success of infection control and occupational health programs; and factors identified by HCWs as important. Method:An extensive literature review was conducted and 15 focus groups held, mostly with frontline HCWs in Toronto. Critical gaps in knowledge were identified and prioritized. Results:Highest priority was given to organizational factors that create a climate of safety. Other priority areas included understanding aerosolization risks and practical measures to control bioaerosols at the source. Conclusions:Further research is warranted to improve safety climate in health care and, specifically, to provide greater protection against respiratory pathogens.

Antineoplastic Drug Contamination of Surfaces Throughout the Hospital Medication System in Canadian Hospitals

We previously reported that there is a potential for antineoplastic drug contamination throughout the hospital medication system (process flow of drug within a facility from delivery to waste disposal) due to the various surfaces contacted by health care workers. This article describes the contamination of these frequently contacted surfaces as well as identifies factors that may be associated with surface contamination. Surfaces which health care workers frequently contact were wiped and the concentration of cyclophosphamide (CP) was determined using high-performance liquid chromatography-tandem mass spectrometry. Descriptive and inferential statistical analyses were performed. A backward stepwise multiple linear regression was conducted to identify determinants associated with surface contamination. Overall, 229 surfaces were sampled, most on two occasions, for a total of 438 surface wipes. The mean CP concentration was 0.201 ng/cm2, the geometric mean 0.019 ng/cm2, and the geometric standard deviation 2.54, with a range of less than detection (LOD) to 26.1 ng/cm2. (Method LOD was 0.356 ng/wipe; factoring in the surface area of the wiped surface, results in a sample LOD ranging from 0.00 to 0.049 ng/cm2). Our study found that frequently contacted surfaces at every stage of the hospital medication system had measureable levels of antineoplastic drug contamination. Two factors were statistically significant with respect to their association with surface contamination: (1) the stage of the hospital medication system, and (2) the number of job categories responsible for drug transport. The drug preparation stage had the highest average contamination. Those hospitals that had two or more drug transport job categories had higher levels of surface contamination. Neither the reported handling of CP prior to wipe sampling nor the cleaning of surfaces appeared to be associated with contamination.

Health Care Workers and Respiratory Protection: Is the User Seal Check a Surrogate for Respirator Fit-Testing?

Many agencies recommend that health care workers wear N95 filtering facepiece respirators (N95-FFR) to minimize occupational exposure to bioaerosols, such as tuberculosis and pandemic influenza. Published standards outline procedures for the proper selection of an N95-FFR model, including user seal checks and respirator fit-testing. Some health officials have argued that the respirator fit-test step should be eliminated altogether, given its additional time and cost factors, and that only a user seal check be utilized to ensure that an adequate face seal has been achieved. One of the aims of the current study is to examine whether a user seal check is an appropriate surrogate for respirator fit-testing. Subjects were assigned an N95-FFR and asked to perform a user seal check (as per manufacturers instructions) after which they immediately underwent a respirator fit-test. Successfully passing a respirator fit-test was based on not detecting a leakage through the face seal (either qualitatively with a test agent or quantitatively with a particulate counter). The sample population consisted of 647 subjects who had never been previously fit-tested (naïve), while the remaining 137 participants were experienced respirator users. Only four of the 647 naïve subjects (0.62%) identified an inadequate seal during their user seal check. Of the 643 remaining naïve subjects who indicated that they had an adequate face seal prior to fit-testing, 158 (25%) failed the subsequent quantitative fit-test and 92 (14%) failed the qualitative fit-test. All 137 experienced users indicated that they had an adequate seal after performing the user seal check; however, 41 (30%) failed the subsequent quantitative fit-test, and 30 (22%) failed the qualitative fit-test. These findings contradict the argument to eliminate fit-testing and rely strictly on a user seal check to evaluate face seal.

Examining factors that influence the effectiveness of cleaning antineoplastic drugs from drug preparation surfaces: A pilot study

Occupational exposure to antineoplastic drugs has been documented to result in various adverse health effects. Despite the implementation of control measures to minimize exposure, detectable levels of drug residual are still found on hospital work surfaces. Cleaning these surfaces is considered as one means to minimize the exposure potential. However, there are no consistent guiding principles related to cleaning of contaminated surfaces resulting in hospitals to adopt varying practices. As such, this pilot study sought to evaluate current cleaning protocols and identify those factors that were most effective in reducing contamination on drug preparation surfaces. Three cleaning variables were examined: (1) type of cleaning agent (CaviCide®, Phenokil II™, bleach and chlorhexidine), (2) application method of cleaning agent (directly onto surface or indirectly onto a wipe) and (3) use of isopropyl alcohol after cleaning agent application. Known concentrations of antineoplastic drugs (either methotrexate or cyclophosphamide) were placed on a stainless steel swatch and then, systematically, each of the three cleaning variables was tested. Surface wipes were collected and quantified using high-performance liquid chromatography–tandem mass spectrometry to determine the percent residual of drug remaining (with 100% being complete elimination of the drug). No one single cleaning agent proved to be effective in completely eliminating all drug contamination. The method of application had minimal effect on the amount of drug residual. In general, application of isopropyl alcohol after the use of cleaning agent further reduced the level of drug contamination although measureable levels of drug were still found in some cases.

Health Care Workers’ Knowledge, Perceptions, and Behaviors Regarding Antineoplastic Drugs: Survey From British Columbia, Canada

Although nurses are knowledgeable regarding the risk of exposure to antineoplastic drugs, they often do not adhere with safe work practices. However, the knowledge, perceptions, and behavior of other health care job categories at risk of exposure has yet to be determined. This study aimed to survey a range of health care workers from British Columbia, Canada about their knowledge, perceptions, and behaviors regarding antineoplastic drugs. A self-administered questionnaire was sent to participants querying the degree of contact with antineoplastics, knowledge of risks associated with antineoplastics, perceptions of personal risk, previous training with respect to antineoplastics, and safe work practices. Subjects were recruited from health care facilities in and around Vancouver. Fishers exact tests were performed to ascertain whether there were differences in responses between job categories. We received responses from 120 participants representing seven different job categories. Pharmacists, pharmacy technicians, and nurses were more knowledgeable regarding risks than other job categories examined (statistically significant difference). Although 80% of respondents were not afraid of working with or near antineoplastics, there were concerns about the suitability of current control measures and practices employed by co-workers. Only half of respondents felt confident that they could handle all situations where there was a potential for exposure. Only one of the perception questions, self-perceived risk of exposure to antineoplastic drugs, differed significantly between job categories. Not all respondents always wore gloves when directly handling antineoplastic drugs. Further, hand hygiene was not regularly practiced after glove usage or after being in an area where antineoplastic drugs are handled. The majority of responses to questions related to safe work practices differed significantly between job categories. Our results suggest that knowledge regarding risks associated with antineoplastic drugs can be improved, especially among job categories that are not tasked with drug preparation or drug administration. There is also a gap between knowledge and compliance with glove usage and hand hygiene.Training is also recommended to improve health care workers’ perceptions of the risks associated with antineoplastic drugs.

Historical occupational isocyanate exposure levels in two Canadian provinces

ABSTRACT Isocyanates such as toluene 2, 4-diisocyanate (TDI), methylene bisphenyl isocyanate (MDI), and hexamethylene diisocyanate (HDI) are known sensitizers and exposure to these chemicals can result in isocyanate-induced asthma—the leading cause of occupational asthma. A newly created exposure database was available containing occupational isocyanate measurements spanning 1981–1996 from Ontario and British Columbia (BC)—two of the largest provinces in Canada. The aim was to describe the historical measurements relative to exposure thresholds, ascertain differences in the data between provinces, and identify time trends. Descriptive statistics of the observations were summarized and stratified by isocyanate species and province. Chi-square tests and Students t-test were performed to determine differences between provinces. To investigate time trends in the odds of a measurement exceeding the limit of detection (LOD) and time-weighted average (TWA), mixed effects logistic regression models were constructed. In total, 6,984 isocyanate measurements were analyzed, the majority of which were below the LOD (79%). Overall, 8.3% of samples were in excess of the 2014 TLV-TWA of 0.005 ppm. Comparing the two provinces, the proportion of samples exceeding the LOD and TLV-TWA was greater in BC for all isocyanate species. Differences in time trends were also observed between provinces—the odds of a sample exceeding the TLV-TWA decreased over time in the case of MDI (Ontario only), TDI (both Ontario and BC), and other isocyanates (BC only). Our finding that a majority of the exposure measurements was below the LOD is similar to that reported by others. Differences between provinces may be due the fact that isocyanates are classified as a designated substance in Ontario and must adhere to specific exposure control regulations. Limitations of the database, such as finite number of variables and measurements available until 1996 only, presents challenges for more in-depth analysis and generalization of results. An argument is made that a Canadian occupational exposure database be maintained to facilitate risk assessments as well as for occupational epidemiology research.

Comparison of qualitative and quantitative fit-testing results for three commonly used respirators in the healthcare sector

ABSTRACT N95 filtering facepiece respirators are used by healthcare workers when there is a risk of exposure to airborne hazards during aerosol-generating procedures. Respirator fit-testing is required prior to use to ensure that the selected respirator provides an adequate face seal. Two common fit-test methods can be employed: qualitative fit-test (QLFT) or quantitative fit-test (QNFT). Respiratory protection standards deem both fit-tests to be acceptable. However, previous studies have indicated that fit-test results may differ between QLFT and QNFT and that the outcomes may also be influenced by the type of respirator model. The aim of this study was to determine if there is a difference in fit-test outcomes with our suite of respirators, 3M - 1860S, 1860, AND 1870, and whether the model impacts the fit-test results. Subjects were recruited from residential care facilities. Each participant was assigned a respirator and underwent sequential QLFT and QNFT fit-tests and the results (either pass or fail) were recorded. To ascertain the degree of agreement between the two fit-tests, a Kappa (Κ) statistic was conducted as per the American National Standards Institute (ANSI) respiratory protection standard. The pass-fail rates were stratified by respirator model and a Kappa statistic was calculated for each to determine effect of model on fit-test outcomes. We had 619 participants and the aggregate Κ statistic for all respirators was 0.63 which is below the suggested ANSI threshold of 0.70. There was no statistically significant difference in results when stratified by respirator model. QNFT and QLFT produced different fit-test outcomes for the three respirator models examined. The disagreement in outcomes between the two fit-test methods with our suite of N95 filtering facepiece respirators was approximately 12%. Our findings may benefit other healthcare organizations that use these three respirators.

Wipe Sampling Method and Evaluation of Environmental Variables for Assessing Surface Contamination of 10 Antineoplastic Drugs by Liquid Chromatography/Tandem Mass Spectrometry

This paper describes a novel wipe sampling and high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) method capable of simultaneously detecting 10 antineoplastic drugs (5-fluorouracil, oxaliplatin, methotrexate, vindesine, ifosfamide, cyclophosphamide, vincristine, vinblastine, docetaxel, and paclitaxel). The good overall recoveries and sensitivity values of this method along with the comparatively short run time (8 min) allows for its use in routine monitoring in health care facilities. The long-term behavior of the studied drugs on contaminated surfaces and the effect of surface roughness on drug recoveries were studied to gain insights about how these environmental variables influence the detection, cleaning, and occupational exposure of these drugs. Surfaces with higher roughness parameter (Ra) values (rougher) had the lowest recoveries while those with lower Ra (smoother) presented the highest recoveries. Long-term assessments evidence distinctive drug behaviors with oxaliplatin, vindesine, vincristine, and vinblastine being the less persistent drugs (~20% was recovered after 24 h) and docetaxel and paclitaxel the most persistent drugs with recoveries of 40% and 80% after 1 month. This information indicates the importance of collecting ancillary information about drug usage (throughput, timing, cleaning procedures, etc.) to interpret the results in the context of potential exposure. Finally, the method was successfully applied to evaluate trace surface contamination down to the single picogram per square centimeter in multiple work areas within three local health care centers on Vancouver Island, Canada.

The development and testing of a tool to assess joint health and safety committee functioning and effectiveness

BACKGROUND Concern regarding functioning and effectiveness of joint health and safety committees (JHSCs) in Ontario hospitals was raised following the Severe Acute Respiratory Syndrome outbreak in 2003. A subsequent literature review revealed a lack of studies focused within the healthcare sector. METHODS A tool to measure JHSC effectiveness was developed by a panel of occupational health and safety experts based on a framework from the healthcare sector. Usability testing was conducted in two phases with members of five hospital JHSCs before, during and after a committee meeting. RESULTS Usability of the tool was scored high overall with an average of > 4 on a 5 point scale across twelve items. Downward adjustment of self-assessment scores was reported following JHSC meetings. CONCLUSION Findings demonstrated that the tool was easy to use, effective in supporting discussion and in assisting participants in reaching consensus on rating a large number of JHSC characteristics. Am. J. Ind. Med. 60:368-376, 2017.