Annals of Occupational Hygiene Advance Access originally published online on May 5, 2006
Annals of Occupational Hygiene 2006 50(7):657-664; doi:10.1093/annhyg/mel023
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Exposure to Antineoplastic Drugs Outside the Hospital Environment
Institute for Risk Assessment Sciences, Utrecht University Utrecht, The Netherlands
*Author to whom correspondence should be addressed. Tel: +31 30 2539440; fax: +31 30 2539499; e-mail: h.kromhout{at}iras.uu.nl
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ABSTRACT |
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 TOP ABSTRACT INTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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Objectives: The objectives were (i) to identify occupational populations outside hospitals working with antineoplastic drugs, (ii) to determine the size of the populations ‘at risk’, (iii) to identify major determinants and routes of exposure outside hospitals and (iv) to estimate exposure levels and frequencies relative to levels found in hospitals.
Methods: The survey consisted of two phases; (i) identification of activities with potential exposure to antineoplastic drugs by literature review, interviews, questionnaires and workplace visits, (ii) exploratory measurements of exposure and surface contamination in selected sectors.
Results: Eight sectors were identified with potential exposure to antineoplastic drugs: pharmaceutical industry, pharmacies, universities, veterinary medicine, nursing homes, home care, laundry facilities, and waste treatment. Four sectors were of primary concern: veterinary medicine, home care, nursing homes and industrial laundries. The populations potentially exposed in these sectors vary considerably (from several tens to thousands of workers), as do their levels of exposure. Exposure measurements collected in the veterinary medicine sector showed that workers are indeed exposed to antineoplastic drugs and, in some cases (on gloves after administration), levels were 15 times higher than levels measured during administration in hospitals. Workers sorting contaminated hospital laundry in industrial laundry facilities were exposed to antineoplastic drugs through inhalation. For the home care and nursing homes sectors the highest exposure levels were found when cleaning toilets and washing treated patients. These two sectors are expected to have the largest exposed population (5000–10 000 individuals).
Conclusions: This study has resulted in a comprehensive overview of populations with potential exposure to antineoplastic drugs. Exposure levels can potentially be high compared with the hospital environment, because exposure routes are complex and awareness of the hazard (and therefore use of protective measures) is low. The number of individuals outside hospitals in The Netherlands exposed to antineoplastic drugs is estimated to be between 5000 and 15 000.
Keywords: antineoplastic drugs • home care • industrial laundry facilities • nursing homes • occupational exposure • veterinary medicine
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INTRODUCTION |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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Exposure to antineoplastic drugs has been associated with adverse health effects (reproduction and carcinogenic) (Selevan et al., 1985; Stücker et al., 1990; Sessink et al., 1994a, 1995; Fransman, W., Peelen, S., Roeleveld, N. et al., manuscript submitted). Exposure to antineoplastic drugs has been extensively studied in The Netherlands. Pharmacy personnel and nurses were shown to be exposed to antineoplastic drugs during hospital tasks and contamination of (work) surfaces by these agents occurs (Sessink et al., 1992, 1994b, 1997; Kromhout et al., 2000; Fransman et al., 2005, Fransman, W., Peelen, S., Hilhorst, S. et al., manuscript submitted). A recent study on dermal exposure to antineoplastic drugs showed that dermal exposure to cyclophosphamide occurs during nursing tasks and antineoplastic drugs were present in bedding and sweat of patients (Fransman et al., 2005). These findings indicate that there is a potential for exposure to antineoplastic drugs in sectors related to hospitals (i.e. home care, nursing homes, pharmacies) and in sectors where people are working with contaminated ‘rest products’ from hospitals (i.e. industrial laundries, waste treatment plants). To our knowledge, exposure to antineoplastic drugs has not been studied in sectors outside hospitals and there is a need to identify possible exposure to these hazardous drugs outside the hospital environment.
The main objectives of this study were; (i) to identify occupational populations outside hospitals working with antineoplastic drugs, (ii) to determine the size of the populations potentially exposed, (iii) to identify major determinants and routes of exposure outside hospitals and (iv) to estimate exposure levels and frequencies relative to those found in hospitals.
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METHODS |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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Identification of exposed population
In the first phase scientific literature and other information sources (e.g. internet) were consulted to perform a structured inventory of all occupational groups that could come in contact with antineoplastic drugs. This information was used to construct a ‘flow diagram’ to describe the route of antineoplastic drugs through different work sectors.
In the second phase all activities with antineoplastic drugs were identified. This information was obtained by walk-through surveys in individual companies and through interviews with company personnel.
Questionnaires were used to get detailed information on work characteristics (i.e. frequency of task performance, use of personal protective equipment) and number of workers involved. Questionnaires were designed based on experience with similar kind of surveys in the hospital setting (Fransman, W., Peelen, S., Roeleveld, N. et al., manuscript submitted; Meijster et al., 2006). For home care and universities a special questionnaire was developed and sent to all individual institutes. This questionnaire contained questions with respect to frequency of use of antineoplastic drugs, methods of use, conditions with respect to personal protective equipment, etc. For nursing homes it was not possible to send a questionnaire to all individual institutes. Here a questionnaire containing similar questions as the ones described above was sent to a small sub-sample of institutes to get a general idea about the use of antineoplastic drugs in this sector. Additional information was obtained from experts in the branch organization.
The total number of workers in each occupational group was obtained from the Central Bureau for Statistics (CBS) and from branch and trade organizations.
Exposure measurements
Exploratory task-based measurements were collected in sectors with high potential for exposure to antineoplastic drugs, to confirm exposure and to get an indication of exposure levels. Dermal exposure was measured through collection of gloves or by washing both hands using an isopropanol solution when no gloves were worn (Fransman et al., 2005). Inhalation exposure was measured through personal sampling using PAS6 samplers with glass fibre filters (diameter: 25 mm) and a flow rate of 2.0 l min–1. Environmental air samples were taken using a stationary high volume sampler (flow = 28.3 l min–1) with glass fibre filters (diameter: 37 mm). All air samples were short-term measurements (maximum 60 min) focusing on the exposure during a specific activity or set of activities. Wipe samples were collected using two tissue and 20 ml of 0.03 M sodium hydroxide solution. Wipe samples were taken from the full surface of the object except for wipe samples from the floor, which were 0.5 m2 of floor surface. Cleaning cloth and cleaning water after cleaning a toilet or living area and washing water and washing cloth used to wash a patient who recently received chemotherapy were collected to look for contamination with antineoplastic drugs.
Measurements were focussed on tasks with carboplatin, cyclophosphamide, or 5-fluorouracil to be representative for exposure to antineoplastic drugs. Samples were analysed for cyclophosphamide using a previously described GC-MSMS analysis method (Sessink et al., 1993). 5-Fluoracil was determined using a previously described HPLC method (Sessink et al., 1992). Carboplatin was determined using voltametry as described by Connor et al. (2005) and Schmaus et al. (2002) for analysis of surface contamination.
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RESULTS |
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Eight sectors were identified with potential exposure to antineoplastic drugs: home care, nursing homes, pharmacies, laundries, waste treatment, pharmaceutical industry, veterinary medicine, and universities (Fig. 1). Detailed information per sector collected by company visits, interviews, and questionnaires elucidated that tasks and complexity of routes and determinants varies widely among all occupational sectors, as does the size of the potentially exposed population. Below the results are discussed per occupational sector.
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Home care
Home care institutions in The Netherlands are agencies that provide assistance in nursing care and domestic work (primarily cleaning) to patients in their own home environment.
For home care of patients or administration of chemotherapy in domestic settings no information could be found in the literature. Literature did describe a trend towards treatment at outpatient clinics and intensive home care in patients receiving chemotherapy (Del Gaudio and Menonna-Quinn, 1998).
In total, 123 900 workers are employed by home care institutions in The Netherlands, of whom, based on the figures of presence of chemotherapy in the home situation, presumably 5000–10 000 work with patients receiving chemotherapy. Results from the questionnaire survey among all Dutch home care institutions (response = 60%; N = 59) showed that mainly nursing tasks are performed by home care institutions, but that also antineoplastic drugs are administered to patients [mainly sub-cutaneous (46%) and oral administration (46%)] (Table 1). This shows that in The Netherlands administering of antineoplastic drugs is not limited to the hospital environment and does (although often prescribed by oncologists) also occur in the home environment performed by non-specialized home care nurses. Gloves are used in the majority of home care institutions during administration, but less frequently during nursing tasks. Some nurses use an additional apron or mask (Table 1). Only 36% of home care institutions were able to give information on the number of clients receiving chemotherapy (either in a hospital or at home). Consequently a large number of nurses unknowingly work with antineoplastic drugs.
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Dermal exposure to antineoplastic drugs was not detected during nursing tasks in home care institutions, except for the gloves used during cleaning (70 ng per pair) (Table 2). Contamination was detected in the cleaning cloth (3314 ng) and cleaning water (0.73 ng ml–1) once (Table 2).
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Nursing homes
In nursing homes (primarily elderly homes in The Netherlands) tasks with potential exposure to antineoplastic drugs were comparable with those in home care institutions. No additional literature was available on working with antineoplastic drugs in these institutions.
The number of nursing homes was >1700 and they employ 
200 000 workers. The number of workers potentially exposed was estimated to be >1000. A survey performed by the branch organization showed that registration of activities was very poor and no information could be given on frequencies of activities with potential exposure to antineoplastic drugs. Nurses reported that patients were occasionally treated with antineoplastic drugs in nursing homes, but generally patients in nursing homes received chemotherapy in outpatient clinics of hospitals and were subsequently nursed in nursing homes.
Measurement results identified that dermal exposure occurred during washing of patients (range: 32–450 ng), but not during emptying a pot/urinal or during cleaning (Table 3). Washing water (5.1 ng ml–1) and cleaning cloths (range: 125–3253 ng) appeared to be contaminated with antineoplastic drugs.
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Pharmacies
Exposure to antineoplastic drugs has been extensively studied in hospital pharmacies (Sessink et al., 1994b, 1997; Fransman et al., 2005). These studies indicate that pharmacy technicians are potentially exposed to antineoplastic drugs during daily activities. The questionnaire in home care institutions indicated that 66% of institutions that administered chemotherapy obtained their antineoplastic drugs (primarily for oral or subcutaneous administration) from pharmacies outside hospitals, and not from hospitals like the remaining 34%. The Royal Dutch Pharmaceutical Society (KNMP) of which more than 90% of all pharmacists are a member stated that the policy was to obtain these treatments as much as possible in ready-to-use form from the pharmaceutical industry to prevent exposure of pharmacy personnel to antineoplastic drugs. Nevertheless, they acknowledged that incidental preparation of antineoplastic drugs in pharmacies (outside hospitals) took place, but that strict protective measures were taken.
Laundries
Nurses are exposed via the skin to antineoplastic drugs while removing contaminated bed sheets from patients receiving chemotherapy (Fransman et al., 2005). Company visits in two laundries showed that contact with (contaminated) bedding occurred while manually sorting laundry. Between 100 and 200 workers were estimated to be involved in these activities. Although work protocols advise wearing of personal protective equipment (especially gloves), gloves were not worn by workers during both visits.
Inhalation exposure was detected in three out of five measurements when sorting contaminated sheets with a median value of 4.5 ng m–3 (Table 4). Contamination was not detected in stationary air samples. Actual dermal exposure was not detected in any of the handwash samples.
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Waste treatment plants
In The Netherlands there is one treatment plant for hospital waste, which receives all chemical and biological hospital waste (
6500 tonnes per year) for combustion. The manual loading of sealed containers from the truck onto a conveyor belt is the only process with potential contact with antineoplastic drugs. This activity is performed by 16 employees in rotating shifts of 2 workers. A previous study showed that the hospital waste containers from oncology wards are contaminated with antineoplastic drugs (Fransman, W., Peelen, S., Hilhorst, S. et al., manuscript submitted). Workers wear gloves when loading containers and, in case of visual contamination or spillage, containers were decontaminated before loading.
Pharmaceutical industry
Most studies on exposure to antineoplastic drugs outside hospitals focus on workers in pharmaceutical industries during the production of antineoplastic drugs. Antineoplastic drugs have been detected on the outside of workers' gloves during almost all tasks and in urine of workers weighing ingredients (Sorsa et al., 1988; Sorsa and Pyy, 1990; Jeebhay et al., 1993; Sessink et al., 1997).
Only one company producing antineoplastic drugs was identified in The Netherlands. Other pharmaceutical plants did not have any activities concerning antineoplastic drugs or were solely distributors. In the company that did produce antineoplastic drugs, 20–40 employees worked at stages of the process where antineoplastic drugs were handled and could be released into the work environment. Exposure during these processes is unlikely, because workers performing these tasks make use of strict control measures and personal protective equipment. Workers are routinely monitored on exposure to antineoplastic drugs and protective measures are improved where necessary.
Veterinary medicine
Antineoplastic drugs are being used on a regular basis in veterinary medicine, primarily treating small pets (dogs and cats) (Pellicaan and Teske, 1999). Preparing and administering of antineoplastic drugs were identified as activities with potential for exposure to antineoplastic drugs. However, conclusions are mainly based on information available from studies in hospital settings.
In The Netherlands, 10–15 veterinary clinics treat pets (primarily dogs and cats) with chemotherapy for a variety of cancers and immunological diseases and between 20 and 100 workers are potentially exposed. During visits of these clinics, dermal exposure and splashes were visible during administration and preparation of antineoplastic drugs, while protective clothing was not consequently worn during these activities. Circumstances under which these treatments and associated activities take place were obviously different from the hospital environment. Nursing tasks were not performed and animals almost always immediately leave the clinic after treatment.
Exposure does occur in veterinary clinics during preparation and administration of antineoplastic drugs and 63% (N = 8) of gloves collected from the veterinarian were found contaminated with carboplatin (Table 5). On one occasion an assistant's gloves were also contaminated with antineoplastic drugs while changing the infusion system (Table 5). Wipe samples from all surfaces in the preparation and administering room were all contaminated with antineoplastic drugs (LAF-cabinet: 63–20 621 ng; floor in preparation room: 3.8–12 ng; door handle: 1.0–13 ng; administering table: 2.7–104 ng) (Table 5).
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Universities
Occupational health departments of Dutch universities reported that antineoplastic drugs were being used there. However, universities did not register the use of these chemicals, which made it impossible to gain insight into the number of workers handling antineoplastic drugs at universities. In general, occupational health professionals of the different universities did provide information that working with any hazardous materials would be performed using strict laboratory protocols minimizing the chance of exposure. This could, nevertheless, not be confirmed for the use of antineoplastic drugs.
In general
Potentially exposed populations in the identified sectors were relatively small, except for the sectors home care and nursing homes (Table 6). The last two columns in Table 6 are an estimate of frequency and intensity of exposure to antineoplastic drugs in each of the identified sectors relative to comparable situations in hospitals, based on all information that was obtained in this study. Home care, nursing homes, and veterinary medicine were compared with oncology nurses in hospitals, while pharmacies and pharmaceutical plants were compared with pharmacy technicians in hospitals. For laundries and waste plants the comparison was made for specific exposure scenarios, which apply to these sectors (handling contaminated bed sheets and contact with waste containers, respectively). Knowledge of the use of antineoplastic drugs at universities was lacking (Table 6).
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DISCUSSION |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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This study showed that exposure to antineoplastic drugs can occur in a variety of occupational sectors outside the hospital environment. In some of the studied sectors the exposure and associated risks were very limited and the number of people potentially exposed rather small. Four sectors were identified where exposure to antineoplastic drugs is potentially high: (i) home care, (ii) nursing homes, (iii) veterinary medicine and (iv) laundry facilities.
When comparing the situation of these four sectors with information from hospitals (Table 6) it is likely that the risk for workers in home care is equal to that of hospital nurses. Their frequency of exposure will probably be lower than that of oncology nurses, because the number of patients treated is believed to be relatively small for an individual nurse. However since awareness of potential exposure is low, protective equipment is hardly used. This might lead to high dermal exposure levels, which is primarily caused by lack of information exchange between hospitals and home care institutions (Table 6). Most home care institutions indicated that registration of patients receiving antineoplastic drugs is poor or non-existing. Even if an employee is aware of the fact that he or she is working with a patient who has received chemotherapy, protocols and guidelines, especially for nursing or cleaning tasks were often not available.
For nursing homes it was more difficult to make a detailed comparison with hospitals since information obtained was not as elaborate as for home care. Nevertheless, it is unlikely that awareness in this sector is better than that observed in home care. Exposure frequencies were believed to be somewhat lower than in home care since patients in nursing homes were more likely to be admitted to the hospital (Table 6).
For laundries, inhalation seems to be the primary route of exposure when actively handling contaminated sheets. Since exposure was not found in the background work environment only workers directly involved in handling sheets seem to be at risk of exposure to antineoplastic drugs. Although dermal exposure was not detected, measurements in hospitals indicate that dermal exposure does occur when handling contaminated sheets (Fransman et al., 2005). The higher frequency of contact with contaminated bed sheets in laundry facilities in combination with the inhalation exposure found in this study, indicates that workers in laundry facilities are potentially higher exposed to antineoplastic drugs than oncology nurses during the handling of bed sheets.
For veterinary medicine, activities performed were very similar to those performed in hospitals except that hardly any ‘nursing tasks’ occurred in veterinary medicine because animals leave the clinics after administration. Since antineoplastic drugs are administered only in a few clinics in The Netherlands and the number of treatments was estimated to be between 500 and 1000 per year, frequency of exposure could be very high for individual workers (Table 6). In addition, use of protective equipment was limited increasing the potential for high dermal exposure levels (Table 6). Based on this we believe that for a small group of veterinarians and assistants exposure might be higher than that observed for oncology nurses in hospitals. This was confirmed by measurements where levels of antineoplastic drugs found on the gloves of veterinary doctors preparing were similar to levels found on gloves in hospitals. The levels found when administering antineoplastic drugs in veterinary medicine were, nevertheless, higher by a factor of 15 than levels found in hospitals (Minoia et al., 1998). An important factor for this is probably the way administration is performed in veterinary medicine. Closed IV-systems with Luer–Lock connections, which is standard procedure in hospitals, are not used in veterinary clinics increasing the chance of leakage of high concentrations of antineoplastic drugs during inserting and releasing the IV system from the animal. The use of antineoplastic drugs in veterinary clinics is undergoing several developments in The Netherlands. New treatments are introduced and more clinics are interested in using chemotherapy. This is stimulated by the pharmaceutical industry increasingly advertising antineoplastic drugs as veterinary drugs and making efforts to get them registered as such. If no regulatory actions are taken this might result in a strong increase in number of workers exposed.
For the pharmaceutical industry, universities, waste plant workers and pharmacies protective measures were believed to be sufficient to prevent exposure when performing daily activities with potential contact with antineoplastic drugs (Table 6). Even though literature shows that exposure is common in some pharmaceutical plants outside The Netherlands (Sorsa et al., 1988; Sorsa and Pyy, 1990; Jeebhay et al., 1993; Sessink et al., 1997), we believe that this information does not reflect the Dutch situation as it was observed during our visit to the plant. State-of-the-art of protective equipment was high and regular monitoring was performed on the ‘high risk’ workers to ensure occupational exposure does not occur. Nevertheless, workers should be cautious in case of calamities or inadequate use of personal protective equipment. This is especially important when working with high levels of antineoplastic drugs, for example in pharmaceutical industry or waste treatment. In these cases compulsory use of hygiene procedures and protocols is essential.
This study succeeded in identifying the most important sectors outside hospitals where potential exposure to antineoplastic drugs exists. The measurements, although only exploratory, confirm this for four sectors with assumed highest exposure: home care, nursing homes, veterinary medicine and laundry facilities. More research is needed to quantify exposure levels to antineoplastic drugs outside hospitals. This paper can be used as an important first step in the identification of sectors where exposure to antineoplastic drugs might exist. It is, nevertheless, important to look beyond the limitations of this study since situations might be different in other countries.
Received January 20, 2006; in final form March 20, 2006
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