Occupational exposure to anticancer drug--potential and real hazards

Prediction of the permeability of antineoplastic agents through nitrile medical gloves by zone classification based on their physicochemical properties

BACKGROUND

Permeability of antineoplastic agents through medical gloves is an important factor that must be considered for the appropriate selection of gloves. However, predicting the permeability of antineoplastic agents through medical gloves based on their physicochemical properties remains difficult. Thus, this study aimed to elucidate the relationship between the physicochemical properties and permeability of antineoplastic agents through medical gloves. Additionally, we tried to predict the risk of permeation of antineoplastic agents through medical gloves based on physicochemical parameters.

METHODS

Ten antineoplastic agents (carboplatin, carmustine, cisplatin, cyclophosphamide, doxorubicin, etoposide, fluorouracil, ifosfamide, oxaliplatin, and paclitaxel) with varying physicochemical properties were investigated, and their permeation rates (PRs) through nitrile medical gloves of varying thicknesses (0.05, 0.07, and 0.1 mm) were measured using a continuous flow in-line cell device. We also determined the apparent permeation clearance (CL_P,app) values of the antineoplastic agents based on their PRs at 240 min (PR₂₄₀) and assessed the relationship between CL_P,app and physicochemical parameters [molecular weight (MW) and logarithm of octanol-water partition coefficient (LogP)].

RESULTS

The CL_P,app values of the 10 antineoplastic agents through nitrile medical gloves (0.05 mm thickness) were significantly correlated with their MWs, but not their LogP values (P = 0.026 and 0.39, respectively; Spearman's rank correlation). This finding indicated that the rates of diffusion of the antineoplastic agents in the glove material showed greater effects on CL_P,app than the rates of absorption into the glove surfaces within 240 min of exposure. We then classified the 10 antineoplastic agents into 3 zones (Zone A, high LogP/low MW drugs; Zone B, high LogP/high MW drugs; and Zone C, low LogP) and found that Zones A, B, and C corresponded to high (PR₂₄₀ > 10 ng/min/cm²), moderate (PR₂₄₀ < 10 ng/min/cm²), and low (no detectable permeation) permeation risk, respectively.

CONCLUSIONS

The permeation risk of antineoplastic agents through nitrile medical gloves within the actual continuous wearing time in clinical settings could be predicted using MW and LogP values. We believe that the proposed zone classification of antineoplastic agents will be a useful tool for predicting the permeation risk of antineoplastic agents through medical gloves.

Measures to prevent the risks associated with exposure to cytostatic drugs in glaucoma filtering surgery

INTRODUCTION

The use of cytostatic drugs such as Mitomycin C and 5-Fluorouracil is well-known in glaucoma filtering surgery, as well as the management of its complications. However, there is a lack of information regarding the preventive measures to be taken by the professional that handles these types of substances.

OBJECTIVE

Raise awareness among professionals of the risks associated with the use of cytostatic drugs without adequate prevention measures.

RESULTS

Review of the available literature and legislation on preventive measures in the management of cytostatic drugs in the medical and ophthalmological field.

CONCLUSIONS

The prevention and awareness of the risks of the qualified professionals that handle these substances is the most important measure to prevent the possible risks. Coordination is necessary with the Occupational Health teams of the Hospital, as well as the professionals and staff involved in the different phases of the process, from the preparation in Hospital Pharmacy to its elimination.

Interstitial pneumonia induced by cyclophosphamide: A case report and review of the literature

Introduction

Recently, interstitial lung disease significantly increases and it is difficult to treat. Cyclophosphamide(CP) is one drug administrated in interstitial lung disease, which can also cause pulmonary fibrosis and lung function lesion. This article present a case which exacerbated interstitial pneumonia after treatment by CP, aiming to enhance the understanding of the side effects of CP and standardize usage of the CP.

Case presentation

A patient of nephrotic syndrome administrated with CP suffered respiratory insufficiency requiring mechanical ventilation. Computed tomography (CT) imaging was compatible with interstitial pneumonia(IP). After treating with multimodal combination therapy (corticosteroids, immune globulins), the patient survived. The clinical characteristics of CP-related lung toxicity and/or pulmonary fibrosis should be paid more attention to avoid the serious outcomes.

Conclusion

Although interstitial lung disease induced by CP is rare, with the current widespread usage of CP increases the risks of diffuse interstitial pneumonia and pulmonary fibrosis, which need to be noted in time to get early treatment.

Evaluation of the PhaSeal Hazardous Drug Containment System

PhaSeal is a containment system designed to ensure the safe preparation and administration of cytostatic drugs and thus reduce environmental contamination to work areas and to medical and support staff. The PhaSeal system was tested in an outpatient setting in Sweden for 1 year during the preparation and administration of cyclophosphamide, fluorouracil, and similar cytostatic drugs. The study was designed to determine the effectiveness of PhaSeal in preventing the leakage of cytostatic drugs frequently reported in a number of studies. Cytostatic drugs were prepared and administered using standard safety procedures, except that a biological safety cabinet was not used. At the conclusion of the study period, environmental contamination was determined from wiping samples of objects and surfaces in the drug preparation room. Neither cyclophosphamide nor fluorouracil was found in any of these samples. Results show that use of the PhaSeal system alone is sufficient to prevent environmental contamination during the preparation of cytostatic drugs.

Evaluation of the permeation of antineoplastic agents through medical gloves of varying materials and thickness and with varying surface treatments

BACKGROUND

Medical gloves are an important piece of personal protective equipment that prevents exposure to antineoplastic agents. The permeability of medical gloves to antineoplastic agents is a crucial factor in the appropriate selection of gloves. However, the relationship between glove permeability and material type, thickness, and surface treatment is poorly understood.

METHODS

A continuous flow in-line cell device was used for the evaluation of the permeation of five antineoplastic agents (etoposide, cyclophosphamide, doxorubicin hydrochloride, paclitaxel, and fluorouracil) through medical gloves. Medical gloves made of three types of materials (chlorinated latex, non-chlorinated latex, and nitrile) were subjected to a permeability test. The antineoplastic agents in test solutions were tested at the highest concentrations employed in general clinical practice. Then, the relationship between glove thickness and permeability was assessed using chlorinated latex gloves with thicknesses of 0.1, 0.15, 0.2, and 0.1 mm × 2 (to represent the practice of "double gloving").

RESULTS

Only cyclophosphamide and fluorouracil showed detectable permeation through the tested latex gloves. The permeability of chlorinated latex was lower than that of non-chlorinated latex. Nitrile gloves showed no detectable permeability to any of the five antineoplastic agents tested. The permeability of chlorinated latex gloves depended on the thickness of the gloves; 0.1 mm × 2 (double gloving) exhibited the highest resistance to permeation by antineoplastic agents.

CONCLUSIONS

The permeability of medical gloves was dependent on the type of material and the surface treatment and decreased as the thickness of the glove increased. The double glove was shown to prevent antineoplastic agent permeation more efficiently than did a single glove of the same total thickness. These results provided important information that will guide the appropriate selection of medical gloves.

Genotoxic Monitoring of Nurses Handling Cytotoxic Drugs

OBJECTIVE

Several biomarkers may be used to detect harmful exposure and individual susceptibility to cancer. Monitoring of biomarkers related to exposure may have a significant effect on early detection of cell transformation, thereby aiding the primary prevention of various chronic and malignant diseases. Nurses who handle cytotoxic drugs are exposed to carcinogenic agents, which have the potential to interrupt the cell cycle and to induce chromosomal aberrations. The presence of high chromosomal aberrations indicates the need for intervention even when exposure to these carcinogens is low.

METHODS

Nationally representative samples of 552 nurses were investigated by a follow-up monitoring system. The measured biomarkers were clinical laboratory routine tests, completed with genotoxicological (chromosome aberrations [CAs] and sister chromatid exchanges [SCEs]) and immunotoxicological monitoring (ratio of lymphocyte subpopulations and lymphocyte activation markers) measured on peripheral blood lymphocytes. Results were compared to the data of 140 healthy, age-matched controls.

RESULTS

In nurses exposed to cytostatics, we observed a significantly increased frequency of CAs and SCEs compared with those in the controls. Cytostatic drug exposure also manifested itself in an increased frequency of helper T lymphocytes. Genotoxicological and immunotoxicological changes, as well as negative health effects (i.e., iron deficiency, anemia, and thyroid diseases), increased among cytostatic exposed subjects.

CONCLUSIONS

These results raised concerns about the protection of nursing staff from chemical carcinogens in the working environment.

Cytogenetic monitoring of pharmaceutical staff working with cytostatic drug preparations: A 5-year follow-up

Introduction. Cytostatic drug preparation in hos pital pharmacies leads to a concentration of expo sure on a few people and requires considerable protective measures.

Methods. To prove the efficiency of those standards, 45 people who routinely prepare cyto static drugs were monitored with cytogenetic tests, Micronucleus-rate (MN), and Sister Chroma tid Exchange-rate (SCE), once a year over a period up to 5 years. All participants of the study received a physical examination before they began prepar ing cytostatic drugs. Baseline MN and SCE were performed at the time. Individual comparisons for the tests between pre- and post-exposure, and a comparison between an exposed and an unex posed group were then performed.

Results. During the 5-year follow-up there were no hints of genotoxic effects as a result of handling cytostatic drugs.

Conclusion. Thus, it appeared that the safety precautions employed at this Institute were ade quate.

Development of a new method for sampling and monitoring oncology staff exposed to cyclophosphamide drug

Treatment using cytotoxic drugs is considered to be the most common treatment for cancers. However, the widespread use of these drugs on the health status of the staff at the oncology department has become a great concern. Due to challenges of sampling and analysis of cytotoxic drugs, the aim of this study was to development a novel practical method called Needle trap devices (NTD) for sampling and analysis of personal exposure to cyclophosphamide drug. The sampler consisted of a stainless steel hyper needle gauge 21 of length 9 cm packed with Carboxen 1000 for adsorbing cyclophosphamide. A total of 41 samples of staff's air breathing zone in different wards of the oncology department were taken with the sampler. Samples were analyzed by gas chromatography coupled with electron capture detector (ECD). Linear range concentration was 212-1062 μg/m(3), and LOD and LOQ were 100 and 191 μg/m(3), respectively. The mean inter-day and intra-day coefficient variations for standards within linear range concentration were 8.9 and 4.8 %, respectively. Detectable levels of cyclophosphamide were measured in 31.7 % of air samples. The developed method is user-friendly, quick, and precise for sampling of airborne cyclophosphamide. The results showed that some staff of the oncology department were exposed to the carcinogenic drug and their health were at risk. Since carcinogens do not have a threshold and oncology staffs with their continuous exposure might be at risk, therefore, proper work practice and adequate control measures are essential to ensure their wellbeing.

Teratogenic effect of cisplatin in rats and the protective role of sodium selenate

Eighty pregnant Sprague-Dawley rats were used in this study. They were allotted to four equal groups. The first group served as a control without any treatment while the other groups were given cisplatin, sodium selenate, and cisplatin+sodium selenate, respectively. Cisplatin was injected intraperitoneally in a dose of 5mg/kgb wt. on the 12th day of gestation while sodium selenate was administered orally in a dose of 0.5mg/kgb wt throughout gestation. Animals were sacrificed on the 20th day of gestation for fetal examination. Cisplatin produced significant elevation in the percentages of late resorption sites and dead foetuses compared with the control group. The mean foetal and placental weights were significantly reduced. Dwarf foetuses and subcutaneous (s/c) haemorrhage were also recorded in cisplatin-treated group. Visceral abnormalities were revealed in the form of dilated nares, anophthalmia and/or microphthalmia, dilated brain ventricles, hypertrophy of the heart, hypoplasia of the lung, hepatomegaly and dilated renal pelvis. Skeletal examination showed wide open fontanel, incomplete ossification of parietal and interparietal bones, incomplete ossification of sternum, reduction in the number or even complete absence of phalanges, sacral and/or caudal vertebrae. Histopathological examination of placentas in cisplatin-treated group revealed severe pathological alterations. Administration of sodium selenate significantly alleviated the afore-mentioned adverse effects of cisplatin on the fetuses and their placentas so we conclude that sodium selenate as an antioxidant has an effective protective role in cisplatin teratogenic effects.

Longitudinal biomonitoring of nurses handling antineoplastic drugs

AIMS AND OBJECTIVES

To assess a possible trend in the genotoxic risk of oncologic nurses during the working year, cytogenetic biomonitoring was performed.

BACKGROUND

Exposure to cytostatic agents is a major occupational concern in oncologic personnel. In contrast to the controlled environment in oncology pharmacies, nurses may be subject to unexpected events of exposure due to the intensive contact with patients.

DESIGN AND METHODS

The entire nursing staff of an oncology inpatient ward (n = 15) participated in a biomonitoring study over a period of nine months using the sister chromatid exchange test and the comet assay to detect DNA strand breaks. Blood samples were taken after a three-week summer break (base level), one, three, six and nine months thereafter. Airborne contaminations of cytotoxics were addressed by chromatographic methods.

RESULTS

With regard to the single monitoring points, the comet assay revealed no significant alteration of the genotoxic burden within nine months. By contrast, the sister chromatid exchange levels were significantly increased after six and nine months when compared with base levels. A trend analysis covering the whole observation period revealed an increase in genotoxicity as shown by the sister chromatid exchange test and the alkaline but not the neutral comet assay. This increase, however, was small and reversible as shown by the trend analysis of sister chromatid exchange rates during the years of service. Air samples were negative for cytotoxic contaminants.

CONCLUSIONS AND RELEVANCE TO CLINICAL PRACTICE

The small, but statistically significant genotoxic burden observed in oncologic nurses of an inpatient ward emphasises the need for a continuing effort to eliminate residual occupational risks. In comparison with historical controls, the current situation is characterised by beneficial safety improvements over the last years. Nevertheless, periodic training and awareness of the problems should be an integral part of advanced education.

Handling chemotherapy drugs-Do medical gloves really protect?

Due to their potential mutagenic, carcinogenic and teratogenic effects occupational exposure to chemotherapy drugs should be kept to a minimum. Utilization of personnel protective devices, especially the use of protective medical gloves, is a mainstay to avoid skin contact. The choice of appropriate gloves is of outstanding importance. For optimal protection in the oncology setting it is essential to establish general guidelines evaluating appropriate materials and defining quality standards. Establishing these guidelines can facilitate better handling and avoid potential hazards and late sequelae. In Europe there are no specific requirements or test methodologies for medical gloves used in the oncology environment. The implementation of uniform standards for gloves used while handling chemotherapy drugs would be desirable. In contrast, in the US medical gloves used to handle chemotherapy drugs have to fulfill requirements according to the ASTM International (American Society of Testing and Materials) standard D 6978-05. Nitrile or natural rubber latex is a preferred basic glove material, while vinyl is considered inappropriate because of its generally increased permeability. For extended exposure to chemotherapy drugs, double gloving, the use of thicker gloves and the frequent change of gloves increases their protective power.

Photocatalytic oxidation of 5-fluorouracil and cyclophosphamide via UV/TiO2 in an aqueous environment

Cytostatic drugs are a class of pharmaceuticals that are increasingly used in cancer therapies; 5-fluorouracil is one of the most commonly used cytostatic (antineoplastic) drugs in the world. This study applied photocatalytic oxidation to remove 5-fluorouracil. Degussa P25 showed a higher photocatalytic degradation efficiency for 5-fluorouracil removal than Aldrich TiO2 and ZnO. Under optimal conditions (20 mg L(-1) TiO2 at pH 5.8), 200 μg L(-1) 5-fluorouracil can be removed within 2 h (k = 0.0375 min(-1)). 5-fluorouracil was found to be decomposed by near-surface OH free radicals produced from valence holes (hvb(+)). At a relatively high concentration, 5-fluorouracil (27.6 mg L(-1)) is >99.9% removed within 4 h by 300 mg L(-1) Degussa P25, while 24 h is required to reach complete mineralization with 96.7% fluoride recovery. Cyclophosphamide is another widely used cancer drug that follows a similar decomposition pathway. Cyclophosphamide (27.6 mg L(-1)) was also >99.9% eliminated within 4 h, but dechlorination and mineralization reached only 79.9% and 55.1%, respectively, after 16 h of irradiation. Together with the results for Microtox(®), it is suggested that the oxidation products of cyclophosphamide are even more recalcitrant and toxic. For engineering practices, despite the fact that photocatalytic oxidation can rapidly remove target antineoplastic, it is also important to further evaluate the treatment efficiency of the photoproducts.

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.

Determination of exposure of dispensary drug preparers to cyclophosphamide by passive sampling and liquid chromatography with tandem mass spectrometry

OBJECTIVES

To determine cyclophosphamide exposure to preparers during tablet crushing and subsequent handling by analyzing indoor air collected using a high-performance volatile organic compounds-solvent desorption (VOC-SD) passive air sampler.

METHODS

The passive sampler was taped to the mask over the mouth of the preparer and indoor air was collected during crushing and preparation of cyclophosphamide tablets (Endoxan®). After collection, the carbon molecular sieve adsorbent of the passive sampler was placed in a centrifuge tube, and 1 mL of carbon disulfide was used to elute cyclophosphamide from the adsorbent. Liquid-liquid extraction with 1 mL of water was performed, and the aqueous phase was used as the test solution. Cyclophosphamide concentration was determined by liquid chromatography with ultraviolet and tandem mass spectrometry detection.

RESULTS

Cyclophosphamide concentration was detected in the range of 7.6-157.7 ng/sampler. Our results showed that low-level exposure occurred near the mouth of the preparer, which could present risks for long-term exposure, especially if combined with multiple toxic drug exposures.

CONCLUSION

The anticancer drug monitoring methodology described here is a simple exposure assessment that can be used to ensure the safety of hospital pharmacy tablet preparers. Furthermore, since the anticancer drug exposure risk is very high for preparers, preparation should be in hood or with face mask.

In vitro evaluation of the protective effects of 4-thujanol against mitomycin-C and cyclophosphamide-induced genotoxic damage in human peripheral lymphocytes

4-Thujanol (sabinene hydrate), a bicyclic monoterpene alcohol, is found in the essential oils of many aromatic and medicinal plants and is widely used as a fragrance and flavouring agent in many different products. The aim of this study was to evaluate the protective effects of 4-thujanol against the genotoxic effects induced by mitomycin C (MMC) and cyclophosphamide (CP) in human lymphocytes, using the chromosome aberrations, sister chromatid exchanges, and micronucleus tests, in the absence and in the presence of S9 mix, respectively. The cells were treated with 0.25 µg/mL MMC and 28 µg/mL CP as alone and cotreated with 13 + 0.25, 26 + 0.25, and 52 + 0.25 µg/mL 4-thujanol + MMC and with 13 + 28, 26 + 28, and 52 + 28 µg/mL 4-thujanol + CP as a mixture. The present study showed that 4-thujanol was unable to reduce the genetic damage induced by MMC, in the absence of S9 mix. On the other hand, probably the metabolites of 4-thujanol act as an antagonist and markedly antagonize CP-induced genotoxicity, in the presence of S9 mix. In general, 4-thujanol + MMC and 4-thujanol + CP decreased the mitotic index, proliferation index and nuclear division index to the same extent or more than those of individual exposure of MMC or CP. In conclusion, 4-thujanol significantly reduced (p < 0.001) the genotoxic damage induced by CP but not MMC when compared with the respective positive control alone. We can suggest that 4-thujanol may improve the chemopreventive effects and may also reduce the harmful side effects of CP, which is widely used in chemotherapy against cancer, without reducing its antiproliferative activities.

Tannic acid mitigates cisplatin-induced nephrotoxicity in mice

Cisplatin (CP) is a well-known chemotherapeutic drug that displays dose-limiting nephrotoxicity. In this study, tannic acid (TA), a naturally occurring plant polyphenol, was evaluated for its antioxidant and antigenotoxicity potential against the CP-induced renal oxidative stress and genotoxicity in Swiss albino mice. The mice were given a prophylactic treatment of TA orally at a dose of 40 and 80 mg/kg body weight (b wt) for 7 consecutive days before the administration of a single intraperitoneal (i.p.) injection of CP at 7 mg/kg b wt. The modulatory effects of TA on CP-induced nephrotoxicity and genotoxicity were investigated by assaying oxidative stress biomarkers, serum kidney toxicity markers, DNA fragmentation, alkaline unwinding, micronuclei assay, and by histopathological examination of kidney architecture. CP administration altered the antioxidant levels, enhanced lipid peroxidation, induced DNA strand breaks, and altered the levels of micronuclei among polychromatic erythrocytes (PCEs) significantly ( p < 0.001). Pretreatment of TA in mice showed significant ( p < 0.001) recovery in antioxidant status, viz., reduced glutathione content and its dependent enzymes, quinone reductase and γ-glutamyl transpeptidase. TA significantly ( p < 0.001) reinstated the normal serum levels of blood urea nitrogen (BUN) and creatinine. TA showed strongly inhibited ( p < 0.001) micronuclei induction, DNA strand breaks, and DNA fragmentation. Thus, TA as a phytochemical protects kidneys through its antigenotoxic activity and antioxidant potential.

Assessment of chromosomal aberrations, micronuclei and proliferation rate index in peripheral lymphocytes from Tunisian nurses handling cytotoxic drugs

Anti-neoplastic agents are widely used in the treatment of cancer and some non-neoplastic diseases. These drugs have been proved to be mutagens, carcinogens and teratogens. To check the eventual effects of anti-cancer drugs on occupationally exposed Tunisian nurses, we used chromosomal aberration assay and micronucleus assay. Both parameters have been used to evaluate cellular DNA damage in the biological monitoring of occupationally exposed workers and each assay has its own aim .We used the proliferation rate index to evaluate the cytotoxic effect of antineoplastic drugs in exposed nurses. The frequency of binucleated micronucleated cells was significantly higher in nurses handling cytostatic drugs than in control. We detected also a significant increase of structural chromosomal aberrations. Control subjects generally had significantly higher values of proliferation rate index compared to expose ones. Our results confirm the genotoxic and the cytotoxic effects of antineoplastic drugs in blood lymphocytes circulation. This study points to the necessity to work under more safe and controlled conditions during the preparation and the administration of anti-cancer drugs.

Immunotoxicity monitoring of hospital staff occupationally exposed to cytostatic drugs

The aim of our study was to investigate the immunotoxicity of occupational cytostatic drug exposure, and to assess the possible effect of confounding factors, such as age and smoking. In this human study, the immunotoxic effect of antineoplastic drugs was investigated among 306 nurses working in oncology chemotherapy units. Results were compared to 98 non-exposed women. The immune status of the subjects was characterized by immune phenotyping of peripheral blood lymphocytes by flow cytometry, using monoclonal antibodies against surface antigens (CD3, CD4, CD8, CD19, CD25, CD45, CD56 and CD71). The killing ability of neutrophil leukocytes was assessed by the measurement of reactive oxygen intermediate production. Occupational exposure to antineoplastic drugs caused shifts in the major lymphocyte subpopulations, resulting in a statistically significant increase in the ratio of B cells. Cytostatic drug exposure also manifested itself in a decreased frequency of CD25 positive, activated T lymphocytes, and increased oxidative burst of neutrophil granulocytes, both of which may have a functional impact on the immune system of exposed subjects. In the younger subjects exposure also caused a shift in T cell subpopulations: a reduction in the cytotoxic T cell population lead to an elevated Th/Tc ratio. In the exposed group, smoking increased activation of T lymphocyte subpopulations. In conclusion, we have demonstrated that low dose occupational cytostatic drug exposure is immunotoxic, and age and smoking modify the effect of exposure.

Assessment of DNA damage in Japanese nurses handling antineoplastic drugs by the comet assay

To clarify genotoxic effects of occupational exposure to antineoplastic drugs in Japan, we examined DNA damage, assessed by the comet assay, in 121 female nurses and 46 female clerks working at three hospitals in the northeast of Japan. The comet assay is considered to be a sensitive and rapid method for DNA strand break detection in individual cells, and tail length and tail moment are used as the comet parameters. Concerning the basal characteristics, the 46 control subjects had higher rates of smoking and coffee-drinking habits and lower hemoglobin than the 121 nurses (p<0.05). The log-transformed tail length in the nurses was significantly longer than that in the control subjects after adjusting for possible covariates such as age and smoking habit (p<0.05). Also, the log-transformed tail length was significantly longer, in the 57 nurses who had handled antineoplastic drugs in the last six months, than that in the 46 control subjects (p<0.05); but, no significant difference in tail length or tail moment was seen between the two nurse groups with and without experience of handling hazardous drugs (p>0.05). These results suggest that Japanese nurses who have worked at hospitals using antineoplastic drugs may have a potential risk of DNA damage. To minimize this risk in Japan, use of biological safety cabinet and appropriate protective equipment, in addition to staff education and training, should be implemented in the healthcare environment.

The multitude and diversity of environmental carcinogens

We have recently proposed that lifestyle-related factors, screening and aging cannot fully account for the present overall growing incidence of cancer. In order to propose the concept that in addition to lifestyle related factors, exogenous environmental factors may play a more important role in carcinogenesis than it is expected, and may therefore account for the growing incidence of cancer, we overview herein environmental factors, rated as certainly or potentially carcinogenic by the International Agency for Research on Cancer (IARC). We thus analyze the carcinogenic effect of microorganisms (including viruses), radiations (including radioactivity, UV and pulsed electromagnetic fields) and xenochemicals. Chemicals related to environmental pollution appear to be of critical importance, since they can induce occupational cancers as well as other cancers. Of major concerns are: outdoor air pollution by carbon particles associated with polycyclic aromatic hydrocarbons; indoor air pollution by environmental tobacco smoke, formaldehyde and volatile organic compounds such as benzene and 1,3 butadiene, which may particularly affect children, and food pollution by food additives and by carcinogenic contaminants such as nitrates, pesticides, dioxins and other organochlorines. In addition, carcinogenic metals and metalloids, pharmaceutical medicines and cosmetics may be involved. Although the risk fraction attributable to environmental factors is still unknown, this long list of carcinogenic and especially mutagenic factors supports our working hypothesis according to which numerous cancers may in fact be caused by the recent modification of our environment.

Phyllanthus maderaspatensis, a dietary supplement for the amelioration of adriamycin-induced toxicity and oxidative stress in mice

The effect of ethanol extract of Phyllanthus maderaspatensis (PME), a popular south Indian dietary supplement, was studied for its chemoprotective property on adriamycin (ADR)-induced toxicity and oxidative stress in mice. Adriamycin toxicity was evaluated biochemically by measuring the serum concentration of lactate dehydrogenase (LDH) and creatinine phosphokinase (CPK). Genotoxicity was evaluated by measuring the frequency of micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow cells. Oxidative stress in the heart tissue was estimated by measuring the glutathione (GSH) levels in the homogenate. The treatment of mice with different doses of PME (400 mg/kg and 600 mg/kg body weight, p.o.,) for 7 days before the administration of a single i.p. dose of ADR (15 mg/kg) exhibited significant protection in a dose-dependent manner. The results clearly indicate that PME has a protective effect against ADR-induced toxicity, as revealed by the decrease in the concentrations of LDH, CPK, and the frequency of MNPCEs. The increased levels of GSH are indicative of the antioxidant property of PME.

Chemical safety and health conditions among Hungarian hospital nurses

In the present study genotoxicological and immunotoxicological follow-up investigations were made on 811 donors including 94 unexposed controls and 717 nurses with various working conditions from different hospitals (The Hungarian Nurse Study). The nurses were exposed to different chemicals: cytostatic drugs, anesthetic, and sterilizing gases, such as ethylene oxide (ETO) and formaldehyde. The measured biomarkers were: clinical laboratory routine tests, completed with genotoxicological (chromosome aberrations [CA], sister chromatid exchange [SCE]), and immune-toxicological monitoring (ratio of lymphocyte subpopulations, lymphocyte activation markers, and leukocyte oxidative burst). The highest rate of genotoxicologically affected donors (25.4%) was found in the group of cytostatic drug-exposed nurses. Comparing geno- and immunotoxicological effect markers, we found that among genotoxicologically affected donors the frequency of helper T cell (Th) lymphocytes, the ratio of activated T and B cells increased, whereas the oxidative burst of leukocytes decreased. In hospitals with lack of protective measures increased CA yields were observed compared to those with ISO 9001 quality control or equivalent measures. Anemia, serum glucose level, thyroid dysfunctions, benign, and malignant tumors were more frequent in the exposed groups than in controls. The hygienic standard of the working environment is the basic risk factor for the vulnerability of nurses. On the basis of these results, it is suggested, that the used cytogenetic and immunological biomarkers are appropriate to detect early susceptibility to diseases. The Hungarian Nurse Study proved that the use of safety measures could protect against occupational exposure at work sites handling cytostatic drugs, anesthetic, and sterilizing gases.

Genotoxic Risks to Nurses from Contamination of the Work Environment with Antineoplastic Drugs in Japan

The aims of the present study were to clarify the work environment contamination by antineoplastic drugs in a hospital ward and to assess the genotoxic risks to nurses who routinely handle antineoplastic drugs in Japan. The exposed group consisted of 19 female nurses who routinely handled antineoplastic drugs. The control group consisted of 18 female nurses who did not handle antineoplastic drugs in the same hospital as the exposed group. The genotoxicity of the 19 antineoplastic drugs used in the hospital ward and 8 wipe samples of the workbench after handling of antineoplastic drugs were measured using the umu assay. Lymphocyte DNA damage (tail length) was measured with alkaline methods of the single cell gel electrophoresis assay (comet assay). Of the 19 antineoplastic drugs, dacarbazine, bleomycin, daunorubicin, doxorubicin, pirarubicin, carboplatin, cisplatin and etoposide induced genotoxicity. Of the 8 sampling d, the umu activity of the wipe sample was positive on 3 d. Contamination of the workbench was found when the nurses handled more drugs than on other days. The medians of the tail length in the comet assay were 8.5 and 5.1 microm, respectively, for the exposed and control groups, with a significant difference (p=0.004 by Mann-Whitney's U-test). In the present study, the nurses of the exposed group were considered to have been exposed to antineoplastic drugs and lymphocyte DNA damage of the exposed group was suggested to be induced by antineoplastic drugs.

Handling Anticancer Drugs: From Hazard Identification to Risk Management?

The potential health hazards involved with antineoplastic agents have been known for decades. Many anticancer drugs are recognized as carcinogens and genotoxins in experimental assays. Second cancers have been recorded in follow-up studies with treated patients. The first findings on occupational exposures among hospital personnel administering chemotherapy were reported only in 1979. Since that time a magnitude of studies have been published using various chemical and biological exposure measurements. These findings prompted improvements in the handling practices of personnel working with anticancer drugs. In spite of strict guidelines for the safe handling of cancer chemotherapeutic agents and extensive improvements in the handling facilities in hospitals, also recent studies have revealed detectable, even if generally much decreased, amounts of indicator drugs in air and surface wipe samples, also including biological samples of personnel in hospital pharmacies and cancer therapy wards. Follow-up measurements show that application of strict safety precautions in hospitals decreases the biological exposure and/or effect markers to the level of unexposed referents. Open information and constant tutoring of personnel to avoid the hazards when working with anticancer drugs is absolutely necessary with the increasing use of these important drugs.

Investigating genetic damage in workers occupationally exposed to methotrexate using three genetic end-points

Genetic damage in workers occupationally exposed to an antineoplastic drug was studied using the micronucleus (MN) test, the comet assay, the hprt gene mutation assay and the TCR gene mutation assay. The subjects were divided into two groups: (i) 21 workers from a plant producing methotrexate (MTX); (ii) 21 controls were matched according to age, gender and smoking. Fresh blood samples were collected from the workers and controls. The results of the MN test showed that the mean micronuclei rate (MNR) and mean micronucleated cell rate (MCR) in workers were 10.10 +/- 0.95 per thousand and 8.05 +/- 0.75 per thousand, respectively, which were significantly higher than those (5.48 +/- 0.82 per thousand and 4.38 +/- 0.58 per thousand) in controls (P < 0.01). It was found in the comet assay that the mean tail length (MTL) of workers and controls were 1.30 +/- 0.06 microm and 0.07 +/- 0.01 microm, respectively. There was a significant difference between workers and controls for MTL (P < 0.01), but the difference between the mean tail moment (MTM, 0.23 +/- 0.03) of workers and MTM (0.17 +/- 0.04) of controls was not significant (P > 0.05). The results of hprt gene mutation assay showed that the average mutation frequency (Mf-hprt) of hprt in workers was 1.00 +/- 0.02 per thousand, which was significantly higher than that (0.86 +/- 0.01 per thousand) in controls (P < 0.01). Meanwhile, the results of TCR gene mutation assay indicated that Mfs-TCR gene mutation frequencies of workers and controls were 6.87 +/- 0.52 x 10(-4) and 1.67 +/- 0.14 x 10(-4), respectively, which were significantly different (P < 0.01). The results of our experiment suggest that genetic damage is detectable in the 21 workers occupationally exposed to methotrexate.

A new high-performance liquid chromatographic/electrospray ionization tandem mass spectrometric method for the simultaneous determination of cyclophosphamide, methotrexate and 5-fluorouracil as markers of surface contamination for occupational exposure monitoring

A new high-performance liquid chromatographic/electrospray ionization tandem mass spectrometric (HPLC/ESI-MS/MS) method was developed for the simultaneous quantification of 5-fluorouracil (5FU), methotrexate (MTX) and cyclophosphamide (CP) in environmental samples. These compounds, commonly used in the treatment of cancer, are recognized as genotoxic. In order to estimate the occupational exposure of hospital personnel handling these drugs, wipe samples were taken from the working surfaces and directly analyzed (with trophosphamide as internal standard) using a reversed-phase capillary column and MS/MS detection. This is the first HPLC/MS/MS method for the simultaneous determination of 5FU, MTX and CP. The present method offers high sensitivity, with detection limits of 1.1 microg l(-1) for MTX and CP and 33.3 microg l(-1) for 5FU, avoiding any sample preconcentration procedure. Rapidity, specificity, high accuracy (mean values between 92.4 and 99.9%) and precision (mean RSD values between 3.4 and 12.1%) make the method suitable for the routine determination of these three antineoplastic drugs.

Highly sensitive high-performance liquid chromatography/selective reaction monitoring mass spectrometry method for the determination of cyclophosphamide and ifosfamide in urine of health care workers exposed to antineoplastic agents

In recent years, the potential for exposure of health care workers to antineoplastic agents has led to the establishment of more restrictive government and professional standards and procedures for handling cytotoxic drugs. Therefore, the detection of low exposure levels is a new and important aim of biological monitoring. In the present paper we report an assay for the simultaneous determination of cyclophosphamide (CP) and ifosfamide (IF) in urine, using electrospray ionization liquid chromatography/tandem mass spectrometry with selective reaction monitoring (HPLC/SRM-MS). A rapid sample preparation procedure uses a solid-phase extraction stage with C18 columns. The urine assay is linear over the range 0.02 to 0.4 microg/L, with lower limits of quantification (LLOQs) of 0.02 and 0.04 microg/L for CP and IF. The accuracy and precision have been carried out through the validation study. The intra-day precision, expressed as relative standard deviation (RSD), is found to be always less than 14.7% for both analytes. The overall precision, assessed on three different days, is less than 15.0%. The recovery of ozaxaphosphorines ranges from 83.5% (CP) to 88.5% (IF) with a RSD always less than 14.6%. The uncertainty of the overall method was also evaluated, to identify possible sources of error. The combined uncertainty was less than 25% over all the days of the validation study. This method is selective and sensitive enough to determine trace levels of CP and IF in a range of urine concentrations relevant to performing low exposure assessment.

β-Glucan inhibits the genotoxicity of cyclophosphamide, adriamycin and cisplatin

The inhibitory effects of beta-glucan (betaG), one of the biological response modifiers, on the induction of chromosomal aberrations in the bone marrow and spermatogonial cells of mice treated with various anti-neoplastic drugs were investigated. beta-Glucan (100 mg/kg bw, i.p.) pre-treatment reduced the total number of cells with structural chromosomal aberrations scored after the treatment with cyclophosphamide (CP) (2.5 mg/kg bw, i.p.) adriamycin (ADR) (12 mg/kg bw, i.p.) and cis-diamminedichloroplatinum-II (cisplatin) (5 mg/kg bw, i.p.) by about 41.1, 26.9 and 57.7% in bone marrow and 44.4, 55 and 57.1% in spermatogonial cells, respectively. This protective effect of beta-glucan could be attributed to its scavenging ability to trap free-radicals produced during the biotransformation of these anti-neoplastic drugs. Beta-glucan also markedly restored the mitotic activity of bone marrow cells that had been suppressed by the anti-neoplastic drugs. These results indicate that in addition to the known immunopotentiating activity of beta-glucan, it plays a role in reducing genotoxicity induced by anti-neoplastic drugs during cancer chemotherapy.

Occupational risk in health care and research

BACKGROUND

Working in the health care and research sectors has been linked to various hazards.

METHODS

Studies published in the peer-reviewed literature that are pertinent to the exposures or diseases relevant to these fields were reviewed.

RESULTS

The most important exposures include infectious agents, formaldehyde, anesthetic agents, antineoplastic drugs, and ethylene oxide. The best-documented evidence is that of infectious risk primarily among clinical personnel. Monitoring studies of persons occupationally exposed to anesthetics clearly demonstrate behavioral effects, possible risk of reproductive problems, as well as cytogenetic effects of unknown significance. The latter two impairments are also observed among those exposed to antineoplastic drugs and ethylene oxide. Exposure to formaldehyde appears to be associated with nasopharyngeal tumors. Whereas increased risk of cancer of certain sites, particularly the brain and lymphohematopoietic system, is found among research and health care personnel, no specific exposure has been linked to these neoplasms.

CONCLUSIONS

Although some results are inconsistent, continued environmental and biological monitoring will allow better assessment of exposures and of implemented protection measures.

A new monitoring method using solid sorbent media for evaluation of airborne cyclophosphamide and other antineoplastic agents

Cyclophosphamide is a known human carcinogen. In July 1999, in a report at a conference on cytotoxic drugs in Sweden, it was indicated that cyclophosphamide (CP) was not effectively controlled by high efficiency particulate air (HEPA) filters.((1)) This then raised a concern that the existing air monitoring methods, which utilize polytetrafluoroethylene (a.k.a. PTFE, or Teflon) or glass fiber filters for evaluation of antineoplastics such as CP in air may also be ineffective for collection and quantification of such agents. It was decided that further evaluation of the existing filter method for monitoring antineoplastics in air be conducted. This evaluation determined that the filter method of monitoring was minimally effective for some antineoplastic agents, and that an alternate method of monitoring should be sought. The method subsequently developed utilizes a solid sorbent tube, Anasorb 708, a methacrylic acid polymer. Evaluation of this sorbent tube for adsorption and desorption properties found it had a greater than 90 percent recovery for both CP and ifosfamide. Other agents evaluated included 5-fluorouracil, doxorubicin, and paclitaxel. All three agents were able to be detected and measured by use of Anasorb 708 solid sorbent tube. Validation of the method was then conducted with air pulled through the tubes via attachment to an air manifold system at air flows ranging from 1.5 to approximately 4.0 liters per minute for up to 24 hours. This evaluation did validate the Anasorb 708 tube as an effective media for collection of airborne concentrations of CP from less than 1 microgram up to approximately 2 mg (2000 microgram) per tube. This corresponds to a concentration range of approximately 0.7 microgram/m(3) (0.0007 mg/m(3)) to 0.7 mg/m(3) in a 5.76 m(3) volume of air. This method can provide accurate information on airborne concentrations of CP for purposes of conducting risk assessments or evaluation of risk management methods.

Biological monitoring of hospital personnel occupationally exposed to antineoplastic agents

To detect trace amounts of urinary cyclophosphamide (CP), ifosfamide (IF) and methotrexate (MTX), sensitive and specific high-performance liquid chromatography/ tandem mass spectrometry (HPLC-MS/MS) procedures, incorporating either liquid-liquid (for CP and IF), or solid-phase, extraction (for MTX) have been developed. Urinary platinum (Pt) was also detected using inductively coupled plasma-mass spectrometry (ICP-MS). These methods showed acceptable imprecision and inaccuracy. The limit of detection (LOD) was 50 ng/l for CP and IF, 200 ng/l for MTX and 1 ng/l for Pt. Biomonitoring was performed on two consecutive days on nine subjects preparing, and seven administering, antineoplastic drugs. Urine was collected at the beginning, at the end and during the work shift. Eighteen urine samples were positive for CP (range: 50-10031 ng/l), whereas IF was detected in one subject only (153 ng/l). LOD was never exceeded for MTX. In urine samples from nurses and pharmacy technicians, Pt was detected in three subjects (range 920-1300 ng/l). These findings were compared with the results from a previous survey carried out in the same hospital when different work practices were in use. The proposed methods are simple, fast and reliable and can be used to identify exposure of hospital personnel handling antineoplastic drugs.

Micronucleus incidence and their chromosomal origin related to therapy in acute lymphoblastic leukemia (ALL) patients: detection by micronucleus and FISH techniques

Micronucleus assay and dual color-fluorescence in situ hybridization (DC-FISH), using centromere-specific and whole chromosome-specific painting probes, are considered a useful screening test to determine the incidence of micronucleus, their origin and contents. The patients with acute lymphoblastic leukemia (ALL), who had undergone chemotherapy, were analysed before and after treatment with vincristine, methotrexate, daunomycin, prednisone, and asparaginase. The incidence of micronuclei after the antileukemic agent treatment was significantly higher than before the treatment. Application of DC-FISH using a combination of whole chromosome-specific painting probes and the same chromosome-specific alpha-satellite centromeric probe showed that there were no significant differences in the micronucleus incidence for any specific chromosome (chromosomes 7, 8, 11, 17, X, and Y). There were no significant differences between the incidence of centromere-positive micronuclei and the incidence of centromere-negative micronucleus. We concluded that antileukemic agents induced the somatic genetic damage but this damage is not related to any specific chromosome studied.

Follow-up genotoxicological monitoring of nurses handling antineoplastic drugs

Most of the antineoplastic drugs used in the treatment of tumors are carcinogenic to humans. Hospital nurses are often subject to possible occupational carcinogen exposure. Exposure may occur during handling and administration of infusion solutions containing cytostatics. A genotoxicological monitoring system to detect genotoxic changes was developed in our laboratory, helping to improve working conditions and subserving primary prevention. Multiple-endpoint follow-up genotoxicological monitoring was performed in peripheral blood lymphocytes (PBLs) among 4 groups of 95 nurses (152 investigations) occupationally exposed to cytostatics. The results were compared to those of historical and industrial controls. The genotoxicological endpoints were the determination of the frequency of sister chromatid exchanges (SCEs) and the cells with high-frequency SCEs (HFC), the frequency of structural and numerical chromosome aberrations. and the measurement of ultraviolet-light-induced unscheduled DNA-repair synthesis (UDS). In Hospital 1, where nurses worked without a safety cabinet, the percentage of cells with chromosome aberrations (AC) was significantly higher than that of the controls. In Hospital 2, where nurses used inadequate safety cabinets (with horizontal airflow), significantly elevated levels of AC, SCE, HFC, and UDS were detected. During follow-up, in Hospital 2 at the time of the second investigation AC was still significantly higher, although safety conditions had been improved. The results indicate the presence of genotoxic damage in hospital nurses working with no or inadequate safety equipment. In Hospitals 3 and 4 where nurses using biological safety cabinets, the results were lower than those in the previous two groups. In Hospital 3 in the first year of the study AC was as at the level of industrial controls. During follow-up in the course of the repeated investigations a fluctuation in AC above the control level and an increase in HFC in yr 4 and 6 of the study were observed. In this group, the fluctuation in AC and HFC during the study points to the possibility of genotoxic exposure with cytostatics despite of the use of suitable safety cabinets, drawing attention to other possible routes of exposure. In Hospital 4, both AC and HFC were elevated. These data corroborate the need to maintain safety measures to avoid exposure, and the necessity of intervention in the case of exposure when using and handling hazardous carcinogenic agents. The results also indicate a certain expression time for genotoxic changes, which can lead to late somatic mutations as well as to a possible higher risk of cancer.

Determination of 5-fluorouracil in environmental samples by solid-phase extraction and high-performance liquid chromatography with ultraviolet detection

5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs. It can be therefore considered to be a model compound for the identification of exposure routes during preparation and administration of cytostatic agents, especially for nucleoside analogue drugs. In this study, an HPLC-UV method was validated for determination of 5-FU in wipe samples by direct analysis of the aqueous solutions and in air samples by using solid-phase extraction (SPE). When samples were pre-treated on styrene-divinylbenzene resin SPE columns, a 20-fold preconcentration of the analyte was achieved. As regards air samples, correlation coefficients were always higher than 0.998 and the limit of detection was assessed at 15 ng on filter. In order to verify the reliability of these procedures, 5-chlorouracil was used as internal standard. The procedure presented here has been applied to the environmental monitoring of occupational exposed subjects. The amount of 5-FU ranged from 0.043 to 0.23 microg/m3 in air samples and from 0.2 to 470.1 microg/dm2 in wipe samples. 5-FU was also detected on the internal side of the gloves (0.07 to 3.77 microg/pair of gloves).

Protection of CHO cells by mutant forms of O6-alkylguanine-DNA alkyltransferase from killing by 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) plus O6-benzylguanine or O6-benzyl-8-oxoguanine

O6-Benzylguanine (BG) is an inactivator of human O6-alkylguanine-DNA alkyltransferase (AGT) currently undergoing clinical trials to enhance cancer chemotherapy by alkylating agents. Mutant forms of AGT resistant to BG in vitro were expressed in CHO cells to determine if they could impart resistance to killing by the combination of BG and 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU). All the BG-resistant mutant proteins tested (P140A, P140K, P138M/V139L/P140K, G156A, P140A/G160R, and G160R) showed a reduced rate of reaction with methylated DNA substrates in vitro. However, when expressed in equal amounts in CHO cells, mutants P140A, P140K, P138M/V139L/P140K, and G160R gave levels of protection from the chloroethylating agent BCNU equivalent to that of wild-type AGT. This indicates that a 10-fold reduction in rate constant did not prevent their ability to repair chloroethylated DNA in the cell. AGT activity was readily lost when CHO cells expressing wild-type AGT were exposed to BG or its 8-oxo metabolite (O6-benzyl-8-oxoguanine), but cells expressing mutants P140A or G160R required 30-fold higher concentrations and cells expressing mutants P140K or P138M/V139L/P140K were totally resistant. When cells were treated with 80 microM BCNU plus BG or 8-oxo-BG, those expressing wild-type AGT were killed when inhibitor concentrations of up to 500 microM were used, whereas cells expressing P140K or P138M/V139L/P140K showed no effect, and cells expressing P140A or G160R showed an intermediate resistance. These results suggest that: (i) appearance of BG-resistant mutant AGTs may be a problem during therapy, and (ii) the P140K mutant AGT is an excellent candidate for gene therapy approaches where expression of a BG-resistant AGT in hematopoietic cells is used to reduce toxicity.

Assessment of DNA damage in nurses handling antineoplastic drugs by the alkaline COMET assay

The widespread use of chemotherapy in the treatment of cancer has led to anxiety about the possible hazards to staff involved in the preparation and administration of cytotoxic agents. Careless handling of antineoplastic drugs may lead to exposure in detectable amounts by means of chemical or biological methods in the body fluids or cell samples but the information about the mutagenic effects of these agents on nurses is limited and inconsistent. DNA damage in peripheral lymphocytes of 30 professional nurses employed in the oncology departments for at least 6 months were examined by the alkaline single cell gel electrophoresis, 'COMET' technique. The results were compared to that of 30 controls with comparable age, sex and smoking habits, not practising in the chemotherapy services. Work characteristics of the exposed nurses and the use of personal protective equipment were also investigated. The DNA damage observed in the lymphocytes of the nurses was significantly higher than the controls (p<0.001). The observed DNA damage was found to be significantly lower (p<0.001) in nurses applying the necessary individual safety protections during their work. Cigarette smoking was not related to increases in DNA damage, also a significant association was not found between the duration of occupational exposure to antineoplastic drugs and the DNA damage.

Human effect monitoring in cases of occupational exposure to antineoplastic drugs: a method comparison

OBJECTIVES

To investigate whether DNA damage increased in subjects possibly exposed to high amounts of antineoplastic agents.

METHODS

The level of genetic damage was determined in peripheral mononuclear blood cells with the sister chromatid exchange test, the alkaline elution technique, and the cytokinesis block micronucleus test.

RESULTS

The supposed increased exposure of the study subjects was caused by a malfunction of a safety hood resulting in leakage of air during preparation of an infusion of an antineoplastic drug. Two months after a new safety hood was installed, the frequencies of micronuclei and sister chromatid exchanges of exposed nurses (n = 10) were still significantly increased when compared with a matched control group (p < 0.01 and p < 0.05, one sided Wilcoxon test, respectively). In a second examination seven months later, the frequency of micronuclei had significantly decreased to control values (p < 0.05, one sided Wilcoxon test, n = 6). Moreover, the study subjects who smoked (n = 8) had significantly increased frequencies of micronuclei and sister chromatid exchanges (p < 0.01 and p < 0.05, one sided U test, respectively). No differences in the rate of DNA damage could be detected with the alkaline elution technique.

CONCLUSIONS

Control measures on the level of biological effect should be performed regularly to ensure maximum safety precautions for workers potentially exposed to genotoxic agents.