Assessment of primary, oxidative and excision repaired DNA damage in hospital personnel handling antineoplastic drugs

The Comet Assay as a Tool in Human Biomonitoring Studies of Environmental and Occupational Exposure to Chemicals-A Systematic Scoping Review

Biomonitoring of human populations exposed to chemical substances that can act as potential mutagens or carcinogens, may enable the detection of damage and early disease prevention. In recent years, the comet assay has become an important tool for assessing DNA damage, both in environmental and occupational exposure contexts. To evidence the role of the comet assay in human biomonitoring, we have analysed original research studies of environmental or occupational exposure that used the comet assay in their assessments, following the PRISMA-ScR method (preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews). Groups of chemicals were designated according to a broad classification, and the results obtained from over 300 original studies (n = 123 on air pollutants, n = 14 on anaesthetics, n = 18 on antineoplastic drugs, n = 57 on heavy metals, n = 59 on pesticides, and n = 49 on solvents) showed overall higher values of DNA strand breaks in the exposed subjects in comparison with the unexposed. In summary, our systematic scoping review strengthens the relevance of the use of the comet assay in assessing DNA damage in human biomonitoring studies.

Factors associated with internal contamination of nurses by antineoplastic drugs based on biomonitoring data from a previous study

Internal contamination of healthcare professionals by antineoplastic drugs (ADs) remains a current occupational health issue, particularly because these compounds are classified as dangerous to handle by the NIOSH. In order to improve preventive actions, a study of the factors associated with this internal contamination was conducted among nursing staff in health care institutions. This study is a statistical analysis of metadata from a cross-sectional observational study conducted among nurses in two French hospitals. The internal contamination of each nurse was assessed in a previous study and was defined by whether or not at least one studied AD was detected in at least one urine sample. Three urine samples and a self-questionnaire were collected for each participant. Analysis of five ADs (cyclophosphamide, ifosfamide, metabolite of 5-fluorouracil, methotrexate, doxorubicin) were performed by liquid chromatography coupled to tandem mass spectrometry. A multivariate stepwise descending regression model was used to determine factors associated with internal contamination by coupling data from a self-questionnaire with internal contamination data. A total of 74 nurses participated to the study and 68 were included for this work: 39 nurses with and 29 without detectable internal ADs contamination. Two protective factors of internal contamination could be identified: a high "glove wearing score" (OR: 0.957; 95%CI: 0.93-0.98; p < 0.01) and a high "total number of years handling ADs and/or caring for patients treated with ADs" (OR: 0.797; 95%CI: 0.67-0.91; p < 0.01). In addition, three factors contributing to internal contamination were identified, namely "feeling sufficiently informed about tasks exposing to ADs" (OR: 9.585; 95%CI: 2.23-57.05; p < 0.01), "disposal of a waste bin containing equipment used for administration of the ADs studied" (OR: 8.04; 95%CI: 1.87-46.08; p < 0.01) and "changing sheets and/or making bed of a patient treated by one of the ADs studied" (OR: 10.479; 95%CI: 1.43-133.30; p < 0.05). Thus, the use of gloves when handling ADs directly or indirectly and the contaminating nature of certain tasks should be taken into account when (1) implementing preventive actions in health care services and (2) training and informing exposed staff. Further studies would be desirable to confirm these results and extend them to other professional categories.

Systematic review of genotoxicity induced by occupational exposure to antineoplastic drugs

With increasing numbers of cancer cases, the use of antineoplastic agents is expected to rise. This will be accompanied by an increase in occupational exposure, which can cause unwanted health effects in workers. Our aim was to give an overview of genotoxic and epigenetic effects after occupational exposure to antineoplastic agents and to assess the concentration-effect relation. Four databases were searched for papers investigating genotoxic and/or epigenetic effects of occupational exposure to antineoplastic agents. Out of the 245 retrieved papers, 62 were included in this review. In this systematic literature review, we confirmed that exposure of healthcare workers to antineoplastic agents can lead to genotoxic damage. However, we observed a lack of data on exposure as well as genotoxic and epigenetic effects in workers other than healthcare workers. Furthermore, gaps in the current knowledge regarding the potential epigenetic effects caused by antineoplastic drug exposure and regarding the link between internal antineoplastic drug concentration and genotoxic and epigenetic effects after occupational exposure to antineoplastic agents were identified, offering a first step for future research.

Exposure to Antineoplastic Drugs in Occupational Settings: A Systematic Review of Biological Monitoring Data

The high toxicity of antineoplastic drugs (ADs) makes them dangerous not only for patients, but also for exposed workers. Therefore, the aim of this review was to provide an updated overview of the biological monitoring of occupational AD exposure in order to extrapolate information useful to improve risk assessment and management strategies in workplaces. Several studies demonstrated that remarkable portions of healthcare workers may have traces of these substances or their metabolites in biological fluids, although with some conflicting results. Nurses, directly engaged in AD handling, were the occupational category at higher risk of contamination, although, in some cases, personnel not involved in AD-related tasks also showed quantifiable internal doses. Overall, further research carried out on greater sample sizes appears necessary to gain deeper insight into the variability retrieved in the reported results. This may be important to understand the impact of the extent of ADs use, different handling, procedures, and cleaning practices, spill occurrence, training of the workforce, as well as the adoption of adequate collective and personal protective equipment in affecting the occupational exposure levels. This may support the achievement of the greatest clinical efficiency of such therapies while assuring the health and safety of involved workers.

Using Behavioral Theory to Enhance Occupational Safety and Health: Applications to Health Care Workers

Work-related morbidity and mortality are persistent public health problems across all US industrial sectors, including health care. People employed in health care and social services are at high risk for experiencing injuries and illnesses related to their work. Social and behavioral science theories can be useful tools for designing interventions to prevent workplace injuries and illnesses and can provide a roadmap for investigating the multilevel factors that may hinder or promote worker safety and health. Specifically, individual-level behavioral change theories can be useful in evaluating the proximal, person-related antecedents (such as perceived behavioral control) that influence work safety outcomes. This article (1) provides a brief overview of widely used, individual-level behavior change theories and examples of their application to occupational safety and health (OSH)-related interventions that involve the health care community; (2) introduces an integrated theory of behavior change and its application to promoting the OSH of health care workers; and (3) discusses opportunities for application of individual-level behavior change theory to OSH research and practice activities involving health care workers. The use of behavioral science to consider the role of individual behaviors in promoting health and preventing disease and injury provides a necessary complement to structural approaches to protecting workers in the health care industry.

Occupational exposure assessment in professionals who manipulate and administer antineoplastic drugs in a university hospital in Southern Brazil

INTRODUCTION

Our goal was to demonstrate the effects of occupational exposure to antineoplastic drugs on oxidative stress parameters and DNA damage in health professionals who manipulate and administer antineoplastic drugs in a University Hospital in Southern Brazil.

METHODS

The case-control study with a longitudinal design, involved 64 individuals, 29 of them pharmacists, pharmacy technicians and nurses who were occupationally exposed to antineoplastic drugs and 35 professionals who were not exposed. Gene mutations were determined by micronucleus from salivary fluid; DNA damage by comet assay and oxidative stress parameters in whole blood were also evaluated.

RESULTS

All workers exposed to antineoplastic drugs used personal protective equipment (PPE). It was demonstrated that the total nonprotein thiol and thiobarbituric acid reactive substances levels showed interaction between group and time, with higher levels one week after handling/administration of antineoplastic drugs in the exposed group (GEE, p ≤ 0.0001 and p = 0,013, respectively). Additionally, there was a group effect on the activities of the catalase and glutathione peroxidase antioxidant enzymes (GEE, p = 0.027 and p ≤ 0.0001, respectively), and workers occupationally exposed to antineoplastic drugs had higher enzyme activities compared to those not exposed. No genotoxic damage was demonstrated through the evaluated parameters.

CONCLUSIONS

Despite the correct use of PPE, professionals occupationally exposed to antineoplastic drugs were more susceptible to oxidative stress than those not exposed. The evaluation of the studied parameters is especially important for the definition of conducts and practices in the area, always in search of guaranteeing the establishment of a rational policy to protect workers' health.

B-Comet Assay (Comet Assay on Buccal Cells) for the Evaluation of Primary DNA Damage in Human Biomonitoring Studies

Many subjects perceive venous blood collection as too invasive, and thus moving to better-accepted procedures for leukocytes collection might be crucial in human biomonitoring studies (e.g., biomonitoring of occupational or residential exposure to genotoxins) management. In this context, primary DNA damage was assessed in buccal lymphocytes (BLs), fresh whole venous, and capillary blood leukocytes, and compared with that in peripheral blood lymphocytes (PBLs)—the most frequently used cells—in 15 young subjects. Mouthwashes were collected after the volunteers rinsed their mouths with normal saline, and BLs were isolated by density gradient centrifugation. Blood samples were collected by venipuncture or by lancet. Anthropometric and lifestyle information was obtained by the administration of a structured questionnaire. As shown in the Bland-Altman plots, the level of agreement between BLs and PBLs lied within the accepted range, we thus enrolled a wider population (n = 54) to assess baseline DNA damage in BLs. In these cells, mean values of tail length (µm), tail intensity (%), and tail moment were 25.7 ± 0.9, 6.7 ± 0.4 and 1.0 ± 0.1, respectively. No significant association was observed between sex and smoking habit with any of the DNA damage parameters. Conversely, underweight subjects displayed significantly higher genomic instability compared with normal weight group (p < 0.05). In conclusion, we successfully managed to set up and update a non-invasive and well-accepted procedure for the isolation of BLs from saliva that could be useful in upcoming biomonitoring studies.

Assessment of the genotoxic potential of a migraine-specific drug by comet and cytokinesis-block micronucleus assays

Background: Eletriptan is a migraine-specific drug-containing the triptan group. In terms of drug safety, the present study aimed to investigate the genotoxic potential of eletriptan.Research design & methods: We conducted our study by using the cytokinesis-block micronucleus cytome (CBMN) assay, a comprehensive method for measuring micronucleus formation, and a sensitive method for detecting DNA-strand breaks. In the assay, cytokinesis-block proliferation index and the frequency of micronuclei were evaluated in lymphocytes treated with three different concentrations (1, 10 and 25 µg/ml) of eletriptan for 48 hours. In comet assays, DNA damage was evaluated in leucocytes treated with three different concentrations (1, 10 and 25 µg/ml) of eletriptan for an hour.Results: Eletriptan did not induce cytotoxicity nor any increased micronuclei frequencies. While the comet parameters % DNA in tail, tail moment, and the olive moment was found to be significantly increased at 10 and 25 µg/ml, the cytokinesis-block proliferation index values were not.Conclusion: These findings suggest that eletriptan is non-cytotoxic but potentially weakly genotoxic at higher concentrations (10 and 25 µg/ml).

Quantification of healthcare workers' exposure to cyclophosphamide, ifosfamide, methotrexate, and 5-fluorouracil by 24-h urine assay: A descriptive pilot study

PURPOSE

The objective of this pilot study was to determine the frequency of urination and the concentration of four hazardous drugs (cyclophosphamide, ifosfamide, methotrexate, and fluorouracil) in workers' 24-h urine samples in relation to exposure to traces with hazardous drugs.

METHODS

The study was conducted in three healthcare centers in the region of Montréal, Quebec, Canada. We recruited healthcare workers (nurses and pharmacy technicians) assigned to the hematology-oncology department. Each participant was asked to collect all urine voided during a 24-h period, to fill out an activity journal documenting tasks performed and to document the use of personal protective equipment. Samples were analyzed for cyclophosphamide, ifosfamide, methotrexate, and alpha-fluoro-beta-alanine (FBAL, the main urinary metabolite of 5-fluorouracil). Drugs were quantified by ultra-performance liquid chromatography-tandem mass spectrometry (positive electrospray MRM mode).

RESULTS

Eighteen healthcare workers (10 nurses and 8 technicians) were recruited and provided consent to participate. Urine samples were obtained between 1 September and 30 September 2019. The number of urinations over the 24-h collection period ranged from 3 to 11 per participant. A total of 128 urine samples were analyzed for the 18 workers. All urine samples were negative for the four antineoplastics tested.

CONCLUSION

No traces of cyclophosphamide, ifosfamide, methotrexate, or FBAL were found in the 24-h urine samples of 18 healthcare workers practicing in three healthcare facilities in Quebec. Although it was feasible to collect 24-h urine samples in this research project, it appears unrealistic to do so recurrently as part of a large-scale surveillance program.

Development and validation of a liquid chromatography tandem mass spectrometry quantification method for 14 cytotoxic drugs in environmental samples

RATIONALE

Cytotoxic drug preparation in hospital pharmacies is associated with chronic occupational exposure leading to a risk of adverse effects. The objective was to develop and validate a quantification method for the following cytotoxic drugs in environmental wipe samples: cyclophosphamide, ifosfamide, cytarabine, dacarbazine, docetaxel, paclitaxel, doxorubicin, epirubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, methotrexate and pemetrexed.

METHODS

The quantification method was developed using liquid chromatography coupled to tandem mass spectrometry and a wiping technique using viscose swabs. Linearity, accuracy, precision, limit of quantification, specificity and stability were assessed, from swab desorbed solution, to validate the analytical method, with respect to ICH guidelines. Environmental samples were collected by wiping five work surfaces of 225 cm² with viscose swabs, during three days.

RESULTS

The quantification method was linear over the calibration range with a lower limit of quantification ranging from 0.5 to 5.0 ng mL^-1 depending on the cytotoxic drug. The intra-day and inter-day relative biases were below 1.5% and 13.5%, respectively. This method was successfully applied to surface-wipe sampling and environmental contaminations ranged from 0.7 to 1840.0 ng cm^-2 for the most contaminated areas.

CONCLUSIONS

This quantification method for 14 cytotoxic drugs was successfully applied to environmental contamination monitoring and could therefore be a useful tool for monitoring and toxicological studies.

Extent of Primary DNA Damage Measured by the Comet Assay in Health Professionals Exposed to Antineoplastic Drugs: A Systematic Review and Meta-Analysis

BACKGROUND

Antineoplastic drugs (ANDs) are a broad group of chemicals showing, at the same time, carcinogenic effects. The potential, albeit true, risk of side effects cannot be accepted, especially if resulting from occupational exposure. The aim of this study was to evaluate the association between occupational exposure to ANDs and the extent of primary DNA damage in health professionals.

METHODS

A systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/Medline, Web of Science, and Scopus were used to perform the literature search. The databases were examined in July 2019. Sub-group, moderator, and cumulative analyses were conducted. The trim and fill method was used in the case of potential publication bias.

RESULTS

Twenty studies were included in the qualitative analysis, and 19 in quantitative evaluation. The pooled effect size was 1.27 [(95% confidence interval (CI) = 0.66-1.88), p = 0.000] based on 1569 subjects. The moderator analysis by duration of exposure showed a positive association between duration of exposure and primary DNA damage.

CONCLUSIONS

This systematic review clearly shows a significant association between occupational exposure to ANDs and the extent of primary DNA damage in health professionals. Considering these results, health professionals should be warned against this potential occupational risk.

Cytostatic drugs and risk of genotoxicity in health workers. A literature review

OBJECTIVE

To analyse the genotoxic risk of cytostatic drugs in health professionals after occupational exposure.

METHOD

Literature was searched for the databases PubMed, Lilacs, The Cochrane Library and Scopus with free and controlled language (MeSH terms) using boolean operators AND and OR. The research was limited to articles published between 2005-2016.

RESULTS

11 articles were selected depending on their relevancy to this review's aim. Nine of the 11 articles proved the existence of damage to genetic material (DNA) of health workers, who were exposed to cytostatics. Furthermore, current security practices do not eliminate the chance of exposure completely. Therefore, the creation of new clinical trials is required.

CONCLUSIONS

Handling cytostatic drugs can cause a genotoxic risk to health workers who are exposed to these substances. This exposure may cause damage on the workers' DNA. There are not enough data to prove a cause-effect relationship between the genotoxic risk and adverse reactions on individuals. Health education will be the main way to raise the awareness and prevention this problem.

Cystostatic drugs and risk of genotoxicity in health workers. A literature review

OBJECTIVE

To analyse the genotoxic risk of cytostatic drugs in health professionals after occupational exposure.

METHOD

The literature was searched using the databases PubMed, Lilacs, The Cochrane Library and Scopus with free and controlled language (MeSH terms) using Boolean operators AND and OR. The research was limited to articles published between 2005-2016.

RESULTS

11 articles were selected depending on their relevancy to this review's aim. Nine of the 11 articles proved the existence of damage to genetic material (DNA) of health workers, who were exposed to cytostatics. Furthermore, current security practices do not fully eliminate the chance of exposure. Therefore, new clinical trials are required.

CONCLUSIONS

Handling cytostatic drugs can cause a genotoxic risk to health workers who are exposed to these substances. This exposure may cause damage to the workers' DNA. There are not enough data to prove a cause-effect relationship between the genotoxic risk and adverse reactions in individuals. Health education will be the main way to raise awareness of and prevent this problem.

Current evidence of education and safety requirements for the nursing administration of chemotherapy: An integrative review

PURPOSE

The administration of chemotherapy is a complex task which has many safety issues. Safe administration of chemotherapy by nurses should be evidence-based. The aim of this integrative review was to synthesise the evidence about education and practice requirements for safe administration of chemotherapy by nurses.

METHOD

A systematic search of four databases identified 17 studies for inclusion in this review. Key words: Nurse, chemotherapy, cytotoxic drug, administration, safety, education. Data extracted from the studies included author, year, aims, design, sample, outcome measures and findings. After screening the articles, extracting study data and completing a summary table, critical appraisal of the studies was completed using the Mixed Methods Appraisal Tool (MMAT).

RESULTS

All the studies focused on strategies to promote patient and nurse safety during nursing administration of chemotherapy. Content analysis identified five themes: governance, process safeguards, communication, interdisciplinary collaboration and education. Key strategies or interventions that increased patient and/or nurse safety identified were standardised computer-generated chemotherapy orders, barcodes, medication safety procedures, education and simulated learning.

CONCLUSIONS

This review found low-level evidence exists about the education and safety requirements for nursing administration of chemotherapy. High-level research is needed to assist healthcare services to select evidence-based educational and safety strategies and provide appropriately resourced work environments to support the safe nursing administration of chemotherapy and deliver the best possible patient outcomes.

Titanium dioxide nanoparticles tested for genotoxicity with the comet and micronucleus assays in vitro, ex vivo and in vivo

The genotoxicity of TiO₂ nanoparticles (NPs) was assessed with the cytokinesis-block micronucleus (CBMN) assay in TK6 lymphoblastoid cells, lymphocytes from human volunteers, and bone marrow erythrocytes from rats exposed in vivo; and with the comet assay (detecting both strand breaks and oxidised purines) in human and rat peripheral blood mononuclear cells (PBMCs). NPs were dispersed using three different methods giving different size distribution and stability. On average, TiO₂ NPs caused no increase in micronuclei in TK6 cells, rat bone marrow erythrocytes or human lymphocytes (though lymphocytes from 3 out of 13 human subjects showed significant increases). PBMCs from rats treated in vivo with a single dose of NPs dispersed by a method with low agglomeration showed an increase in strand breaks after 1 day. TiO₂ NPs dispersed in a stable, non-agglomerated state induced DNA strand breaks at 75 μg/cm² after 4 h exposure of human PBMCs and at 15 μg/cm² and 75 μg/cm² after 24 h exposure, but no increase in DNA oxidation was seen. Overall, NPs in an agglomerated state did not cause DNA damage. However, at the individual level, significant increases in strand breaks were seen in PBMCs from most of the volunteers. Cells from one volunteer showed positive effects in all conditions and both tests, while cells from another volunteer appeared to be completely resitant to TiO₂ NPs. The implication is that some individuals may be more sensitive than others to effects of this nanomaterial. Differences seen in results obtained with the micronucleus and the comet assay may be due to the mechanisms underlying the genotoxic effects of TiO₂ NPs and the different endpoints represented by the two assays.

Mutagenicity assessment of environmental contaminations in a hospital centralized reconstitution unit

INTRODUCTION

Cytotoxic drug exposure of hospital staff preparing intravenous chemotherapy is a major issue and related mutagenic risks should be more explored. The aim of this study was to assess the mutagenicity of several cytotoxic mixtures prepared at fixed concentrations, and the mutagenicity of environmental samples collected in a hospital centralized reconstitution unit. In parallel cytotoxic exposure in environmental samples was quantified.

METHODS

Environmental samples were performed by wiping method using swabs in five critical production unit areas. Mutagenicity was assessed with a liquid microplate AMES test using two salmonella typhimurium strains (TA98 and TA100), in prepared cytotoxic mixtures containing 14 cytotoxic drugs (cyclophosphamide, cytarabine, dacarbazine, docetaxel, doxorubicin, epirubicin, etoposide, 5-fluorouracil, gemcitabine, ifosfamide, irinotecan, methotrexate, paclitaxel and pemetrexed) according a dichotomous strategy and in environmental samples. Cytotoxic drugs were quantified in samples using liquid chromatography coupled to mass tandem spectrometry.

RESULTS

Mutagenesis was observed for the mix of 14 cytotoxic drugs with TA98 strain ± S9 fraction but not TA100 strain. After dichotomous approach, only doxorubicin and epirubicin exposure were associated to mutagenesis. The mutagenesis observed was expressed at lower concentrations with the mix of the 14 drugs than with anthracyclins alone, assuming a synergistic effect. Despite measurable level of cytotoxic contamination in environmental samples, no mutagenesis was highlighted in Ames tests performed on these environmental samples.

CONCLUSIONS

The analyses carried out show the conservation of the mutagenicity of cytotoxic drugs found in very low quantities in the environment. The traces of cytotoxic drugs found in our unit regularly exceed the limits given by some authors. This approach may be considered as a new tool to monitor environmental contamination by cytotoxic drugs.

ACVIM small animal consensus statement on safe use of cytotoxic chemotherapeutics in veterinary practice

The purpose of this report is to offer a consensus opinion of ACVIM oncology diplomates and technicians on the safe use of cytotoxic chemotherapeutics in veterinary practice. The focus is on minimizing harm to the personnel exposed to the drugs: veterinary practitioners, veterinary technicians, veterinary staff, and pet owners. The safety of the patient receiving these drugs is also of paramount importance, but is not addressed in this statement. Much of the information presented is based on national recommendations by Occupational Safety and Health Administration, National Institute for Occupational Safety and Health, United States Pharmacopeia, and other published regulations. These directives reflect an abundance of caution to minimize exposure to medical personnel, but large-scale studies about the consequences of long-term occupational exposure are not available in veterinary medicine. Challenges in the delivery of optimal treatment safely and economically to veterinary patients in general practice without access to a veterinary oncologist or other specialist, because of costs or proximity, remain.

Primary DNA Damage in Dry Cleaners with Perchlorethylene Exposure

BACKGROUND

Perchloroethylene is a halogenated solvent widely used in dry cleaning. International agency of research on cancer classified this chemical as a probable human carcinogen.

OBJECTIVE

To evaluate the extent of primary DNA damage in dry cleaner workers who were exposed to perchloroethylene as compared to non-exposed subjects. The effect of exposure modifying factors such as use of personal protective equipment, perceived risk, and reported safe behaviors on observed DNA damage were also studied.

METHODS

59 exposed and non-exposed workers were selected from Yazd, Iran. All the 33 exposed workers had work history at least 3 months in the dry cleaning shops. Peripheral blood sampling was performed. Microscope examination was performed under fluorescent microscope (400×). Open comet software was used for image analysis. All biological analysis was performed in one laboratory.

RESULTS

Primary DNA damage to leukocytes in dry cleaners was relatively high. The median tail length, %DNA in tail, and tail moment in exposed group were significantly higher than those in non-exposed group. There was no significant difference between smokers and nonsmokers in terms of tail length, tail moment, and %DNA in tail. There was no significant correlation between duration of employment in dry cleaning and observed DNA damage in terms of tail length, tail moment and %DNA in tail. Stratified analysis based on exposed and nonexposed category showed no significant relationship between age and observed DNA damage.

CONCLUSION

Occupationally exposure to perchloroethylene can cause early DNA damage in dry cleaners.

A review of surface wipe sampling compared to biologic monitoring for occupational exposure to antineoplastic drugs

The potential for adverse health effects from occupational exposure to antineoplastic drugs (AD) is well known. Control measures recommended by the NIOSH Alert ^[3] include medical and biologic monitoring, and environmental monitoring where available. At present no guidelines or published best practices exist to guide EHS managers on how to carry out this biologic or environmental monitoring. Studies investigating surface wipe sampling for AD have been numerous in the past decade, but very limited research exists to correlate surface contamination with actual absorption by pharmacists and nurses. This article reviews the studies with concurrent surface wipe sampling and urine monitoring for the same AD, and tests their correlation. Methodologic limitations are reviewed. Twenty-one studies were identified that concurrently measured surface contamination by AD by wipe sampling and AD absorption by urine monitoring. Two studies directly evaluated the AD by wipe sampling and urine levels and neither found a statistically significant correlation. Six studies reported a decrease in both surface and urine levels following interventions to reduce contamination or exposure. Only one study directly evaluated the personal protective equipment and handling techniques employed by the studied workers, which can be viewed as a major confounder of absorption. While no statistically significant correlation was found between wipe sampling and urine monitoring for AD, decreases in urine and wipe levels following interventions to reduce exposure were noted. Limitations in the data and recommendations for future research are reviewed.

Salient Features and Outline of the Joint Japanese Guidelines for Safe Handling of Cancer Chemotherapy Drugs

The purpose of this paper is to introduce the outline and describe the salient features of the “Joint Guidelines for Safe Handling of Cancer Chemotherapy Drugs” (hereinafter, “Guideline”), which were published in July 2015. The purpose of this Guideline is to provide guidance to protect against occupational exposure to hazardous drugs (HDs) to all medical personnel involved in cancer chemotherapy, including physicians, pharmacists, and nurses and home health-care providers. The Guideline was developed according to the Medical Information Network Distribution Service guidance for developing clinical practice guidelines, with reference to five authoritative guidelines used worldwide. PubMed, Cumulative Index to Nursing and Allied Health Literature, Ichushi-Web, and Cochrane Central Register of Controlled Trials were used for a systematic search of the literature. Eight clinical questions (CQs) were eventually established, and the strength of recommendation for each CQ is presented based on 867 references. The salient features of the Guideline are that it was jointly developed by three societies (Japanese Society of Cancer Nursing, Japanese Society of Medical Oncology, and Japanese Society of Pharmaceutical Oncology), contains descriptions including the definition of HDs and the concept of hierarchy of controls, and addresses exposure control measures during handling of chemotherapy drugs. Our future task is to collect additional evidence for the recommended exposure control measures and to assess whether publication of the Guideline has led to adherence of measures to prevent occupational exposure.

Testing an Intervention to Decrease Healthcare Workers' Exposure to Antineoplastic Agents

PURPOSE/OBJECTIVES

To develop and test a worksite intervention that protects healthcare workers who handle antineoplastic drugs from work-related exposures. 
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DESIGN

Intervention study. 
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SETTING

A university hospital in a large midwestern metropolitan area and its outpatient chemotherapy infusion clinic.
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SAMPLE

163 staff (nurses, pharmacists, and pharmacy technicians) who work with antineoplastic agents.
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METHODS

A self-report survey measured workplace and individual factors to assess use of personal protective equipment (PPE). Wipe samples were tested for surface contamination. An intervention incorporating study findings and worker input was developed.
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MAIN RESEARCH VARIABLES

PPE use was the dependent variable, and the independent variables included knowledge of the hazard, perceived risk, perceived barriers, interpersonal influence, self-efficacy, conflict of interest, and workplace safety climate. 
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FINDINGS

PPE use was lower than recommended and improved slightly postintervention. Self-efficacy and perceived risk increased on the post-test survey. Chemical residue was found in several areas. Awareness of safe-handling precautions improved postintervention. The unit where nurses worked was an important predictor of safety climate and PPE use on the pretest but less so following the intervention. 
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CONCLUSIONS

Involving staff in developing an intervention for safety ensures that changes made will be feasible. Units that implemented workflow changes had decreased contamination. 
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IMPLICATIONS FOR NURSING

Worksite analysis identifies specific targets for interventions to improve antineoplastic drug handling safety.

Workplace Activity in Health Professionals Exposed to Chemotherapy Drugs: An Otoneurological Perspective

Introduction The manipulation of antineoplastic drugs presents high risk for accidents and occupational diseases. Objective To evaluate the auditory and vestibular systems of workers who are exposed to chemotherapeutic treatment in the University Hospital of Universidade Federal de Santa Maria, Brazil, and to identify the use of individual protection equipment, related to the obtained results. Methods This study is a cross-sectional study using a quantitative method. We evaluate 33 male and female workers, ranging from 21-60 years old, of the nursing and pharmacy sectors. The workers underwent conventional Audiologic Assessment; Transient Evoked Otoacoustic Emissions; and Computerized Vectoelectronystagmography. Results The majority of the sample was female (90.9%). Individual protection equipment was used by 90.9% of the workers. Complaints of dizziness were reported by 56.25% of nursing workers and 52.94% of pharmacy workers. Audiological and vestibular assessment results were within normal limits, 96.97% and 74.20%, respectively. However, audiometric configuration of notch type was identified in 75.75% of all workers. Audiometric notches (76%) and altered caloric test (100%) were often associated with decreased use of coal masks. Conclusion Among the workers evaluated, the vestibulocochlear system was within the normal limits. The presence of notch configuration indicates the need to use individual protection equipment.

Occupational Exposure to Antineoplastic Agents

Approximately 8 million health care workers are unnecessarily exposed to highly toxic drugs used to treat cancer; antineoplastic drugs can contribute to negative health effects for these workers. The drugs have been detected in the urine of workers and on the floors and counters of worksites. Safety precautions that could reduce the risk of exposure are underutilized. This cross-sectional study of 163 oncology health care workers used a survey to measure workplace and individual factors, and environmental sampling to measure surface contamination. The study objective was to identify potential exposures to antineoplastic drugs and factors influencing safety behavior. Personal protective equipment (PPE) use was lower than recommended; unit of employment was significantly associated with PPE use. Chemical residue from antineoplastic drugs was found, revealing potential exposures. Workplace safety must be a higher organizational priority. The contamination of common work areas where PPE use is not expected was of utmost concern.

[Not Available]

BACKGROUND

There is increasing evidence that traces of hazardous drugs occur in the urine of health care professionals who are exposed to these drugs.

OBJECTIVE

To review the scientific literature regarding urinary monitoring of health care professionals exposed to antineoplastic drugs through their work.

DATA SOURCES

A search of PubMed using the Medical Subject Headings 'occupational exposure' and 'antineoplastic agents' and of Google Scholar using the terms 'antineoplastic', 'urine', and 'occupational exposure'.

STUDY SELECTION AND DATA EXTRACTION

The analysis covered all articles in English or French pertaining to health care professionals exposed to hazardous drugs in the workplace, published from January 1, 2010, to December 31, 2015. Articles that did not discuss the results of urine tests and those concerning veterinarians, as well as literature reviews, editorials, letters to the editor, and conference abstracts, were excluded.

DATA SYNTHESIS

Twenty-four articles were retained. The studies were conducted in 52 health care institutions in 7 countries. They included 826 workers exposed to hazardous drugs and 175 controls, specifically nurses (n = 16 studies), pharmacists (n = 10), pharmacy technicians (n = 8), physicians (n = 7), health care aides (n = 2), and others (n = 8). Various analytical methods were used to quantify the presence of 13 hazardous drugs, primarily cyclophosphamide (n = 16 studies), platinum-based drugs (n = 7), and alpha-fluoro-beta-alanine, a urine metabolite derived from 5-fluorouracil (n = 3). The proportion of workers with positive results ranged from 0% (n = 10 studies) to 100% (n = 4). Considering only those studies that allowed calculation of the rate of workers with at least one positive urine sample (n = 23), the total proportion was 21% (173/809 workers, for all methods and drugs combined).

CONCLUSION

Twenty-four studies on urine monitoring were conducted in 7 countries between 2010 and 2015. In several studies, no traces of drugs were detected in urine.

Surface wipe sampling for antineoplastic (chemotherapy) and other hazardous drug residue in healthcare settings: Methodology and recommendations

Surface wipe sampling for various hazardous agents has been employed in many occupational settings over the years for various reasons such as evaluation of potential dermal exposure and health risk, source determination, quality or cleanliness, compliance, and others. Wipe sampling for surface residue of antineoplastic and other hazardous drugs in healthcare settings is currently the method of choice to determine surface contamination of the workplace with these drugs. The purpose of this article is to review published studies of wipe sampling for antineoplastic and other hazardous drugs, to summarize the methods in use by various organizations and researchers, and to provide some basic guidance for conducting surface wipe sampling for these drugs in healthcare settings.  Recommendations on wipe sampling methodology from several government agencies and organizations were reviewed. Published reports on wipe sampling for hazardous drugs in numerous studies were also examined. The critical elements of a wipe sampling program and related limitations were reviewed and summarized.  Recommendations and guidance are presented concerning the purposes of wipe sampling for antineoplastic and other hazardous drugs in the healthcare setting, technical factors and variables, sampling strategy, materials required, and limitations. The reporting and interpretation of wipe sample results is also discussed.  It is recommended that all healthcare settings where antineoplastic and other hazardous drugs are handled consider wipe sampling as part of a comprehensive hazardous drug "safe handling" program. Although no standards exist for acceptable or allowable surface concentrations for these drugs in the healthcare setting, wipe sampling may be used as a method to characterize potential occupational dermal exposure risk and to evaluate the effectiveness of implemented controls and the overall safety program. A comprehensive safe-handling program for antineoplastic drugs may utilize wipe sampling as a screening tool to evaluate environmental contamination and strive to reduce contamination levels as much as possible, using the industrial hygiene hierarchy of controls.

Applicability of the comet assay in evaluation of DNA damage in healthcare providers' working with antineoplastic drugs: a systematic review and meta-analysis

BACKGROUND

Unintended occupational exposure to antineoplastic drugs (ANDs) may occur in medical personnel. Some ANDs are known human carcinogens and exposure can be monitored by genotoxic biomarkers.

OBJECTIVE

To evaluate the obstacles to obtaining conclusive results from a comet assay test to determine DNA damage among AND exposed healthcare workers.

METHODS

We systematically reviewed studies that used alkaline comet assay to determine the magnitude and significance of DNA damage among health care workers with potential AND exposure. Fifteen studies were eligible for review and 14 studies were used in the meta-analysis.

RESULTS

Under random effect assumption, the estimated standardized mean difference (SMD) in the DNA damage of health care workers was 1.93 (95% CI: 1.15-2.71, p < 0.0001). The resulting SMD was reduced to 1.756 (95% CI: 0.992-2.52, p < 0.0001) when the analysis only included nurses. In subgroup analyses based on gender and smoking, heterogeneity was observed. Only for studies reporting comet moment, I2 test results, as a measure of heterogeneity, dropped to zero. Heterogeneity analysis showed that date of study publication was a possible source of heterogeneity (B = -0.14; p < 0.0001).

CONCLUSIONS

A mixture of personal parameters, comet assay methodological variables, and exposure characteristics may be responsible for heterogenic data from comet assay studies and interfere with obtaining conclusive results. Lack of quantitative environmental exposure measures and variation in comet assay protocols across studies are important obstacles in generalization of results.

Reproductive health risks associated with occupational exposures to antineoplastic drugs in health care settings: a review of the evidence

OBJECTIVES

Antineoplastic drugs are known reproductive and developmental toxicants. Our objective was to review the existing literature of reproductive health risks to workers who handle antineoplastic drugs.

METHODS

A structured literature review of 18 peer-reviewed, English language publications of occupational exposure and reproductive outcomes was performed.

RESULTS

Although effect sizes varied with study size and population, occupational exposure to antineoplastic drugs seems to raise the risk of both congenital malformations and miscarriage. Studies of infertility and time to pregnancy also suggested an increased risk for subfertility.

CONCLUSIONS

Antineoplastic drugs are highly toxic in patients receiving treatment, and adverse reproductive effects have been well documented in these patients. Health care workers with long-term, low-level occupational exposure to these drugs also seem to have an increased risk of adverse reproductive outcomes. Additional precautions to prevent exposure should be considered.

Antineoplastic drugs determination by HPLC-HRMS(n) to monitor occupational exposure

The purpose of this study was to develop a simple, direct, multiresidue highly specific procedure to evaluate the possible surface contamination of selected antineoplastic drugs in several hospital environment sites by using wipe test sampling. 5-fluorouracil (5-FU), carboplatin (C-Pt), cyclophosphamide (CYC), cytarabine (CYT), doxorubicin (DOX), gemcitabine (GEM), ifosfamide (IFO), methotrexate (MET), and mitomycin C (MIT) belong to very different chemical classes but show good ionization properties under electrospray ionization (ESI) conditions (negative ion mode for 5-FU and positive ion mode in all other cases). HPLC (high performance liquid chromatography) coupled with HRMS (high resolution mass spectrometry) appears to be the best technique for direct analysis of these analytes, because neither derivatization nor complex extraction procedure for polar compounds in samples is requested prior the analysis. Sample preparation was limited to washing wipes with appropriate solvents. Chromatographic separation was achieved on C18 reversed phase columns. The HPLC-HRMS/MS method was validated in order to obtain robustness, sensitivity and selectivity. LLOQ (lower limit of quantitation) values provided a sensitivity good enough to evidence the presence of the drugs in a very low concentration range (<1 pg/cm(2) ). The method was applied for a study of real wipe tests coming from many areas from a hospital showing some positive samples. The low quantitation limits and the high specificity due to the high resolution approach of the developed method allowed an accurate description of the working environment that can be used to define procedural rules to limit working place contamination to a minimum. Copyright © 2015 John Wiley & Sons, Ltd.

Cleaning Efficiencies of Three Cleaning Agents on Four Different Surfaces after Contamination by Gemcitabine and 5-fluorouracile

Occupational exposure to antineoplastic drugs has been documented for decades showing widespread contamination in preparation and administration areas. Apart from preventive measures, efficient cleaning of surfaces is indispensable to minimize the exposure risk. The aim of this study was to evaluate the efficiency of three cleaning agents after intentional contamination by gemcitabine (GEM) and 5-fluorouracile (5-FU) on four different surface types usually installed in healthcare settings. Glass, stainless steel, polyvinylchloride (PVC), and laminated wood plates were contaminated with 20 ng/μl GEM and 2 ng/μl 5-FU solutions. Wipe samples were analyzed for drug residues after cleaning with a) distilled water, b) aqueous solution containing sodium dodecyl sulfate (10 mM) and 2-propanol (SDS-2P), and c) Incides N (pre-soaked) alcoholic wipes. Quantification was performed by high-performance liquid chromatography (HPLC) for GEM and gas chromato-graphy-tandem mass spectrometry (GCMS/MS) for 5-FU. Recovery was determined and cleaning efficiency was calculated for each scenario. Mean recoveries were 77-89% for GEM and 24-77% for 5-FU and calculated cleaning efficiencies ranged between 95 and 100% and 89 and 100%, respectively. Residual drug amounts were detected in the range nd (not detected) - 84 ng GEM/sample and nd - 6.6 ng 5-FU/sample depending on surface type and cleaning agent. Distilled water and SDS-2P had better decontamination outcomes than Incides N wipes on nearly all surface types, especially for GEM. Regarding 5-FU, the overall cleaning efficiency was lower with highest residues on laminated wood surfaces. The tested cleaning procedures are shown to clean glass, stainless steel, PVC, and laminated wood with an efficiency of 89-100% after contamination with GEM and 5-FU. Nevertheless, drug residues could be verified by wipe samples. Pure distilled water and SDS in an alcoholic-aqueous solution expressed an efficient cleaning performance, especially with respect to GEM. The study results demonstrate the need to adapt cleaning procedures to the variety of drugs and surface types to develop effective decontamination strategies.

Adherence to Precautionary Guidelines for Compounding Antineoplastic Drugs: A Survey of Nurses and Pharmacy Practitioners

Precautionary guidelines detailing standards of practice and equipment to eliminate or minimize exposure to antineoplastic drugs during handling activities have been available for nearly three decades. To evaluate practices for compounding antineoplastic drugs, the NIOSH Health and Safety Practices Survey of Healthcare Workers was conducted among members of professional practice organizations representing primarily oncology nurses, pharmacists, and pharmacy technicians. This national survey is the first in over 20 years to examine self-reported use of engineering, administrative, and work practice controls and PPE by pharmacy practitioners for minimizing exposure to antineoplastic drugs. The survey was completed by 241 nurses and 183 pharmacy practitioners who compounded antineoplastic drugs in the seven days prior to the survey. They reported: not always wearing two pairs of chemotherapy gloves (85%, 47%, respectively) or even a single pair (8%, 10%); not always using closed system drug-transfer devices (75%, 53%); not always wearing recommended gown (38%, 20%); I.V. lines sometimes/always primed with antineoplastic drug (19%, 30%); and not always using either a biological safety cabinet or isolator (9%, 15%). They also reported lack of: hazard awareness training (9%, 13%); safe handling procedures (20%, 11%); and medical surveillance programs (61%, 45%). Both employers and healthcare workers share responsibility for adhering to precautionary guidelines and other best practices. Employers can ensure that: workers are trained regularly; facility safe-handling procedures reflecting national guidelines are in place and support for their implementation is understood; engineering controls and PPE are available and workers know how to use them; and medical surveillance, exposure monitoring, and other administrative controls are in place. Workers can seek out training, understand and follow facility procedures, be role models for junior staff, ask questions, and report any safety concerns.

Chemotherapy safety in clinical veterinary oncology

Exposure to chemotherapy is a health hazard for all personnel in facilities that store, prepare, or administer antineoplastic agents. Contamination levels have been measured as much as 15 times higher in the veterinary medicine sector than in human facilities. Recent publications in human and veterinary medicine indicate that exposure extends beyond the clinic walls to affect the patient's home and family. This article provides an update on the advances in chemotherapy safety, the current issues, and the impact on cancer management in veterinary medicine.

Identification of Knowledge Gaps Regarding Healthcare Workers' Exposure to Antineoplastic Drugs: Review of Literature, North America versus Europe

We have been examining the issue of healthcare workers' exposure to antineoplastic drugs for nearly a decade and have observed that there appears to be more publications on the subject matter originating from Europe than from North America. The concern is that findings from Europe may not be generalizable to North America because of differences in handling practices, regulatory requirements, and training. Our objective was to perform a literature review to confirm our observation and, in turn, identify gaps in knowledge that warrants addressing in North America. Using select keywords, we searched for publications in PubMed and Web of Science. All papers were initially classified according to the originating continent and then categorized into one or more subject categories (analytical methods, biological monitoring, occupational exposure, surface contamination, and probability of risk/exposure). Our review identified 16 papers originating from North America and 55 papers from Europe with surface contamination being the subject matter most often studied overall. Based on our results, we are of the opinion that North American researchers need to further conduct dermal and/or urinary drug contamination studies as well as assess the exposure risk faced by healthcare workers who handle antineoplastic drugs. Trends in exposure levels should also be explored.

Assessment of genotoxic effects in nurses handling cytostatic drugs

Several antineoplastic drugs have been classified as carcinogens by the International Agency for Research on Cancer (IARC) on the basis of epidemiological findings, animal carcinogenicity data, and outcomes of in vitro genotoxicity studies. 5-Fluorouracil (5-FU), which is easily absorbed through the skin, is the most frequently used antineoplastic agent in Portuguese hospitals and therefore may be used as an indicator of surface contamination. The aims of the present investigation were to (1) examine surface contamination by 5-FU and (2) assess the genotoxic risk using cytokinesis-block micronucleus assay in nurses from two Portuguese hospitals. The study consisted of 2 groups: 27 nurses occupationally exposed to cytostatic agents (cases) and 111 unexposed individuals (controls). Peripheral blood lymphocytes (PBL) were collected in order to measure micronuclei (MN) in both groups. Hospital B showed a higher numerical level of contamination but not significantly different from Hospital A. However; Hospital A presented the highest value of contamination and also a higher proportion of contaminated samples. The mean frequency of MN was significantly higher in exposed workers compared with controls. No significant differences were found among MN levels between the two hospitals. The analysis of confounding factors showed that age is a significant variable in MN frequency occurrence. Data suggest that there is a potential genotoxic damage related to occupational exposure to cytostatic drugs in oncology nurses.

Chromosomal damage in peripheral blood lymphocytes from nurses occupationally exposed to chemicals

In the present study, we evaluated the induced genome damage in peripheral blood lymphocytes from a sample of nurses occupationally exposed to low doses of different chemicals. A comprehensive multi-biomarker approach using cytogenetic endpoints was employed for analyzing chromosomal aberrations (CAs) and sister chromatid exchange (SCE) assay. The study included 20 nurses and 20 control subjects matched in age, gender and smoking habits. Nurses were exposed to different chemicals, such as cytostatic drugs, anaesthetics, formaldehyde and other sterilizing gases. Significant differences were found between exposure group and control group in terms of SCEs frequency (p < 0.001) but not in terms of replication index value (p = 0.845) and CAs (p = 0.236). Regression analyses indicated that the age and the exposure years did not influence the amount of the chromosomal damage among nurses. Vice versa, among controls, a positive correlation was found between the number of SCEs and age. In conclusion, our results suggest that a continuous long-term exposure to low doses of chemicals could result in increased levels of SCEs among nurses. This data emphasize the importance of biomonitoring nurses and other hospital workers handling drugs.

Multicentre study for the evaluation of mutagenic/carcinogenic risk in nurses exposed to antineoplastic drugs: assessment of DNA damage

OBJECTIVES

People who handle antineoplastic drugs, many of which classified as human carcinogens by International Agency for Research on Cancer, are exposed to low doses in comparison with patients; however, the long duration of exposure could lead to health effects. The aim of this work was to evaluate DNA damage in white blood cells from 63 nurses who handle antineoplastic drugs in five Italian hospitals and 74 control participants, using different versions of the Comet assay.

METHODS

Primary DNA damage was assessed by using the alkaline version of the assay on leucocytes, whereas to detect DNA oxidative damage and cryptic lesions specifically, the Comet/ENDO III assay and the Comet/araC assay were performed on leucocytes and lymphocytes, respectively.

RESULTS

In the present study, no significant DNA damage was correlated with the work shift. The exposed population did not differ significantly from the reference group with respect to DNA primary and oxidative damage in leucocytes. Strikingly, in isolated lymphocytes treated with araC, lower data dispersion as well as a significantly lower mean value for the percentage of DNA in the comet tail was observed in exposed participants as compared with the control group (p<0.05), suggesting a potential chronic exposure to crosslinking antineoplastic drugs.

CONCLUSIONS

Although stringent rules were adopted at national and international levels to prevent occupational exposure to antineoplastic drugs, data reported in this study support the idea that a more efficient survey on long-lasting exposures at very low concentrations is needed.

Antimutagenic properties of Mangifera indica L. stem bark extract and evaluation of its effects on hepatic CYP1A1

Mangifera indica stem bark extract (MSBE) is a Cuban natural product which has shown strong antioxidant properties. In this work, the antimutagenic effect of MSBE was tested against 10 well-known mutagens/carcinogens in the Ames test in the absence or presence of metabolic fraction (S9). The chemical mutagens tested included: cyclophosphamide, mitomycin C, bleomycin, cisplatin, dimethylnitrosamine (DMNA), benzo[a]pyrene (BP), 2-acetylaminofluorene (2-AAF), sodium azide, 1-nitropyrene (1-NP) and picrolonic acid. Protective effects of the extract were also evaluated by comparing the efficiency of S9 fraction obtained from rats treated during 28 days with oral doses of MSBE (50-500 mg/kg) with that obtained from rats treated with vehicle (control) to activate bleomycin and cyclophosphamide in the Ames test. MSBE concentrations between 50 and 500 μg/plate significantly reduced the mutagenicity mediated by all the chemicals tested with the exception of sodium azide. Higher mutagenicity was found when bleomycin and cyclophosphamide (CP) were activated by control S9 than by MSBE S9. In addition, inhibition of CYP1A1 microsomal activity was observed in the presence of MSBE (10-20 μg/ml). We can conclude that besides its potent antioxidant activity previously reported, MSBE may also exert a chemoprotective effect due to its capacity to inhibit CYP activity.

A study protocol for the evaluation of occupational mutagenic/carcinogenic risks in subjects exposed to antineoplastic drugs: a multicentric project

Background

Some industrial hygiene studies have assessed occupational exposure to antineoplastic drugs; other epidemiological investigations have detected various toxicological effects in exposure groups labeled with the job title. In no research has the same population been studied both environmentally and epidemiologically. The protocol of the epidemiological study presented here uses an integrated environmental and biological monitoring approach. The aim is to assess in hospital nurses preparing and/or administering therapy to cancer patients the current level of occupational exposure to antineoplastic drugs, DNA and chromosome damage as cancer predictive effects, and the association between the two.

Methods/Design

About 80 healthy non-smoking female nurses, who job it is to prepare or handle antineoplastic drugs, and a reference group of about 80 healthy non-smoking female nurses not occupationally exposed to chemicals will be examined simultaneously in a cross-sectional study. All the workers will be recruited from five hospitals in northern and central Italy after their informed consent has been obtained.

Evaluation of surface contamination and dermal exposure to antineoplastic drugs will be assessed by determining cyclophosphamide on selected surfaces (wipes) and on the exposed nurses' clothes (pads). The concentration of unmetabolized cyclophosphamide as a biomarker of internal dose will be measured in end-shift urine samples from exposed nurses.

Biomarkers of effect and susceptibility will be assessed in exposed and unexposed nurses: urinary concentration of 8-hydroxy-2-deoxyguanosine; DNA damage detected using the single-cell microgel electrophoresis (comet) assay in peripheral white blood cells; micronuclei and chromosome aberrations in peripheral blood lymphocytes. Genetic polymorphisms for enzymes involved in metabolic detoxification (i.e. glutathione S-transferases) will also be analysed.

Using standardized questionnaires, occupational exposure will be determined in exposed nurses only, whereas potential confounders (medicine consumption, lifestyle habits, diet and other non-occupational exposures) will be assessed in both groups of hospital workers.

Statistical analysis will be performed to ascertain the association between occupational exposure to antineoplastic drugs and biomarkers of DNA and chromosome damage, after taking into account the effects of individual genetic susceptibility, and the presence of confounding exposures.

Discussion

The findings of the study will be useful in updating prevention procedures for handling antineoplastic drugs.