Micronucleus induction and FISH analysis in buccal cells and lymphocytes of nurses administering antineoplastic drugs

Blood molecular profile to predict genotoxicity from exposure to antineoplastic drugs

Genotoxicity is an important information that should be included in human biomonitoring programmes. However, the usually applied cytogenetic assays are laborious and time-consuming, reason why it is critical to develop rapid and economic new methods. The aim of this study was to evaluate if the molecular profile of frozen whole blood, acquired by Fourier Transform Infrared (FTIR) spectroscopy, allows to assess genotoxicity in occupational exposure to antineoplastic drugs, as obtained by the cytokinesis-block micronucleus assay. For that purpose, 92 samples of peripheral blood were studied: 46 samples from hospital professionals occupationally exposed to antineoplastic drugs and 46 samples from workers in academia without exposure (controls). It was first evaluated the metabolome from frozen whole blood by methanol precipitation of macromolecules as haemoglobin, followed by centrifugation. The metabolome molecular profile resulted in 3 ratios of spectral bands, significantly different between the exposed and non-exposed group (p < 0.01) and a spectral principal component-linear discriminant analysis (PCA-LDA) model enabling to predict genotoxicity from exposure with 73 % accuracy. After optimization of the dilution degree and solution used, it was possible to obtain a higher number of significant ratios of spectral bands, i.e., 10 ratios significantly different (p < 0.001), highlighting the high sensitivity and specificity of the method. Indeed, the PCA-LDA model, based on the molecular profile of whole blood, enabled to predict genotoxicity from the exposure with an accuracy, sensitivity, and specificity of 92 %, 93 % and 91 %, respectively. All these parameters were achieved based on 1 μL of frozen whole blood, in a high-throughput mode, i.e., based on the simultaneous analysis of 92 samples, in a simple and economic mode. In summary, it can be conclude that this method presents a very promising potential for high-dimension screening of exposure to genotoxic substances.

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.

Development and application of a liquid chromatography coupled to mass spectrometry method for the simultaneous determination of 23 antineoplastic drugs at trace levels

The goal of this study was to develop a method for the simultaneous quantification of 23 commonly used antineoplastic drugs in a hospital pharmacy, using ultra-high pressure liquid chromatography separation coupled to tandem mass spectrometry detection (UHPLC-MS/MS). The following drugs were investigated: 5-fluorouracil, cytarabine, ganciclovir, gemcitabine, dacarbazine, methotrexate, pemetrexed, busulfan, topotecan, rentitrexed, ifosfamide, cyclophosphamide, etoposide, irinotecan, doxorubicin/epirubicin, vincristine, docetaxel, paclitaxel, daunorubicin, idarubicin, vinblastine, oxaliplatin and carboplatin. The chromatographic separation was performed on a phenyl-hexyl column (2.1 ×100 mm, 1.7 µm) with a gradient elution of methanol and water containing 10 mM ammonium formate adjusted to pH 4.9. All compounds were analyzed in less than 13 min and detected with a triple quadrupole mass spectrometer operating in MRM mode. Limits of detection (LODs) and limits of quantification (LOQs) were comprised between 0.01 and 5 ng.mL^-1, and between 0.5 and 5 ng.mL^-1, respectively. Accuracies ranged between 117% and 83% at the LOQ, intermediate and upper LOQ concentrations, with relative standard deviations (RSD) inferior to 8%, for all the antineoplastic drugs. Finally, the UHPLC-MS/MS method was successfully applied to the analysis of surface samples to evaluate the chemical contamination by these highly toxic compounds in a chemotherapy preparation unit in a hospital pharmacy with the purpose of monitoring the exposure of health care professionals.

Evaluation of the genotoxic and antigenotoxic effects of exopolysaccharide pullulan in human lymphocytes in vitro

Pullulan is a biocompatible and water-soluble exo-polysaccharide produced by primary strains of the fungus Aureobasidium pullulans. It is frequently used in the pharmaceutical and food industries. In this study, possible cytotoxic effect of pullulan was assessed using the MTT assay in the human breast cancer (MCF-7) cell line. Micronucleus (MN), micronucleus-FISH (MN-FISH), random amplified polymorphic DNA (RAPD-PCR), and comet assays were used to investigate genotoxic and antigenotoxic effects of pullulan against mitomycin C (MMC) (at MN assay) and hydrogen peroxide (at comet assay) in human lymphocytes. Antigenotoxicity was determined using two different applications: 1 h pretreatment and simultaneous treatment. In the MTT assay, pullulan significantly reduced the cell viability at 15.6-2000 μg/mL compared to the control. No significant alterations in MN rates were found in human lymphocytes treated with different concentrations of pullulan compared to the control. In contrast, co-treatment of pullulan and MMC decreased the frequency of MN in almost all the treatment concentrations and durations compared to the MMC. No significant change was observed in the frequency of the centromere-positive C + or negative C- MNi compared to the positive control. In comet assay, pullulan did not affect comet tail intensity compared to the negative control. On the contrary, pullulan in combination with H₂O₂ significantly decreased tail intensity at almost all the concentrations compared to the positive control. The changes occurring in RAPD-PCR profiles following pullulan treatments included an increase or decrease in band intensity and gain or loss of bands. These results indicate that exopolysaccharide Pullulan is not genotoxic; moreover, it possesses a protective effect against MMC and H₂O₂ induced genotoxicity. In breast cancer cells, pullulan induced cytotoxic/anti-proliferative effect.

Evaluation of Genetic Damage in Persons Occupationally Exposed to Antineoplastic Drugs in Serbian Hospitals

INTRODUCTION

Although useful in the treatment of malignant cells, antineoplastic drugs (ANPDs) as chemical genotoxic agents, can interfere with normal cell physiology causing genetic damage and unfavourable health effects, especially in occupationally exposed persons. The Cytokinesis-block Micronucleus (CBMN) Cytome assay has been widely used in human biomonitoring studies as a reliable biomarker of chemical genotoxic exposure.

OBJECTIVES

Our comprehensive research was conducted in order to evaluate micronuclei as a marker for preventive medical screening purposes for persons occupationally exposed to ANPDs.

METHODS

Using the CBMN Cytome test, peripheral blood lymphocytes of 201 control and 222 exposed subjects were screened for genetic damage.

RESULTS

Age and gender influenced micronucleus (MN) frequency, but smoking habit did not. The mean micronuclei frequencies and other parameters of the CBMN Cytome test [numbers of binuclear lymphocytes with one (MN1) or two (MN2) micronuclei] were significantly higher in the group of exposed persons. Positive correlation between duration of occupational exposure and MN frequency was revealed.

CONCLUSIONS

The results of our study performed on a large sample confirmed the capacity of the CBMN Cytome assay to serve as a reliable biomarker of long-term ANPD exposure.

Genotoxic effects of tobacco use in residents of hilly areas and foot hills of Western Ghats, Southern India

Smoking and smokeless tobacco consumption is a significant risk factor that provokes genetic alterations. The present investigation was to evaluate the biomarkers of genotoxicity including micronucleus (MN), chromosome aberrations (CA) and DNA strand breaks among tobacco consumers and control individuals residing in hilly areas of Western Ghats, Tamilnadu, South India. This study included 268 tobacco consumers with equal number of controls. The tobacco consumers were divided into Group I (<10 years of tobacco consumption with an age range from 15 to 35 years) and group II (>10 years consumption above 35 years of age). Chromosome aberration (CA) and comet assay were performed using blood and micronucleus assay from exfoliated buccal epithelial cells obtained from tobacco consumers and controls. Elevated levels of CA were found in group II (Chromatid type: 2.39 ± 1.13 and chromosome type: 1.44 ± 1.24) exposed subjects, high micronucleus and DNA damage (TL:4.48 ± 1.24 and TM:3.40 ± 1.58) levels were significantly (p < 0.05) observed in both smoking and smokeless tobacco consumers when comparison with group I and controls. This study also observed a lack of awareness among the tobacco consumers about the harmful health effects of tobacco. Tobacco consumption contributes to the significant alteration in genetic materials. In addition, a high rate of spontaneous abortion was also seen in the studied population.

Occupational exposure to cytotoxic drugs: the importance of surface cleaning to prevent or minimise exposure

Healthcare workers who prepare or administer cytotoxic agents run the risk of exposure, and the risks for health are real even at doses lower than those applied in cancer patients, because, in theory, no dose is safe. The most common and problematic route of exposure is through the skin, especially as work surfaces can remain contaminated even after cleaning. This pilot study aimed to demonstrate the importance of having an effective surface decontamination protocol by determining surface contamination with cyclophosphamide, 5-fluorouracil, and paclitaxel as the most common cytotoxic drugs in an oncology day service. Samples were collected before and after drug handling and analysed with high performance liquid chromatography with diode array detection (HPLC-DAD). Of the 29 samples collected before drug handling 23 were contaminated, five of which with more than one drug. Of the 30 samples collected after drug handling 25 were contaminated, eight of which with more than one drug. The two time points did not significantly differ, which evidences a widespread contamination and ineffective cleaning. This calls for revising the cleaning protocol and handling procedure to place contamination under control as much as possible.

Forgotten public health impacts of cancer - an overview

Cancer is one of the diseases of greatest concern in developed countries and much effort has been invested in discovering and developing therapeutics for curing cancer. Despite the improvements in antineoplastic therapeutics in the last decades, cancer is still one of the most harmful diseases worldwide. The global burden of cancer also implies financial costs: these can be direct costs, such as those related to treatment, care, and rehabilitation and indirect, which include the loss of economic output due to missed work (morbidity costs) and premature death (mortality costs). There are also hidden costs such as health insurance premiums and nonmedical expenses that are worth noting. This paper intends to present an overview of the generally forgotten impacts that the increasing number of cancer cases can have on the environment, workers who handle antineoplastic drugs, and health services. The knowledge available of each of the impacts will be addressed and discussed regarding the expected development. Overall, lessons learnt reflect on the impact of cancer through aspects not commonly evidenced in the literature or even considered in socio-economic analysis, in part due to the fact that these are difficult to contemplate in direct and indirect cancer costs already defined. Attention may be drawn to the need of continuous investment in prevention to reduce the negative impact on the environment, and in the health of workers who handle antineoplastic drugs for patients' treatment.

Evaluation of apoptosis induced by exposure to antineoplastic drugs in peripheral blood lymphocytes of nurses

Cytostatic antineoplastic drugs are considered carcinogenic and mutagenic risk factors for health workers who are occupationally exposed to them; however, the molecular mechanisms underlying these effects remain to be elucidated. Therefore, the present study aimed to investigate the underlying mechanisms of antineoplastic drugs-induced apoptosis of peripheral blood lymphocytes (PBLs) obtained from oncology nurses handling antineoplastic drugs. A microRNA (miRNA/miR) polymerase chain reaction (PCR) array was performed to analyze the expression levels of miRNAs in the PBLs from 3 trained nurses occupationally exposed to antineoplastic drugs. The effects of miR-34a on cell proliferation and apoptosis in temozolomide (TMZ) treated PBLs were analyzed by cell counting kit-8 and flow cytometry assays. The protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein, caspase-3 and caspase-9 were determined by western blot analysis, and miR-34a expression levels were detected using quantitative reverse transcription-PCR. The results of the present study demonstrated that miR-34a was significantly upregulated in oncology nurses that were occupationally exposed to antineoplastic drugs. In addition, TMZ suppressed cell proliferation and induced apoptosis, by promoting the expression of miR-34a, in a dose-dependent manner, and also inhibited the expression of Bcl-2. Furthermore, knockdown of miR-34a was able to reverse the reduction of cell proliferation and promotion of apoptosis induced by TMZ in PBLs. Together, these results indicated that abnormal expression of miR-34a may be considered a diagnostic marker in nurses occupationally exposed to antineoplastic drugs.

Chromosomal aberrations, sister chromatid exchanges, and micronuclei in lymphocytes of oncology department personnel handling anti-neoplastic drugs

OBJECTIVE

Concern exists regarding the possible hazards to the personnel handling anti-neoplastic drugs. The purpose of the present study was to assess the genotoxicity induced by anti-neoplastic agents in oncology department personnel.

MATERIALS AND METHODS

To do this, the frequency of chromosomal aberrations (CAs) induced in peripheral blood lymphocytes was assessed at G₀ phase of the cell cycle using metaphase analysis, cytokinesis block-micronucleus (MN) assay and sister chromatid exchange (SCE) assay. These cytogenetic end points were measured among 71 nurses in oncology department and 10 drugstore personnel handling and preparing anti-neoplastic drugs. The results were compared to those of 74 matched nurses for age and sex not exposed to any anti-neoplastic agents.

RESULTS

There was no significant difference between the age of study subjects and control group (p > 0.05). The results showed that the mean frequency of cytogenetic damages in terms of CAs [chromatid breaks (p = 0.01), chromosome breaks (p = 0.005), total CAs (p = 0.001)], MN formation (p = 0.001), and SCE (p = 0.004) in lymphocytes of personnel handling anti-neoplastic drugs were significantly higher than those in control unexposed group.

CONCLUSION

Results of the present study demonstrate the cytogenetic damage in peripheral blood lymphocytes of oncology department personnel. Suitable training and proper knowledge when handling anti-neoplastic drugs are emphasized to avoid potential health hazards caused by cytostatic agents.

Assessment of genotoxic and molecular mechanisms of cancer risk in smoking and smokeless tobacco users

Inexpensive forms of tobacco are widely used in developing countries such as India. We have evaluated genotoxicity endpoints (chromosome aberrations, micronucleus frequency, comet assay) and polymorphisms of the XRCC1 and p53 genes among smokers and smokeless tobacco (SLT) users in rural Tamilnadu, South India. Cytogenetic, DNA damage and SNP analyses were performed on peripheral blood samples; micronucleus frequency was measured in peripheral blood and buccal mucosa exfoliated cells. Both categories of tobacco users had elevated levels of genotoxic damage. SNP analysis of tobacco users revealed that 17% carry the XRCC1 gln399gln genotype and 19% carry the p53 pro72pro genotype. Both genotypes are associated with increased risk of cancer.

FISH in micronucleus test demonstrates aneugenic action of rotenone in a common freshwater fish species, Nile tilapia (Oreochromis niloticus)

Aneuploidies are numerical genetic alterations that lead to changes in the normal number of chromosomes due to abnormal segregation during cell division. This type of alteration can occur spontaneously or as a result of exposure to mutagenic agents. The presence of these agents in the environment has increased concern about potential damage to human health. Rotenone, derived from plants of the genera Derris and Lonchocarpus, is a product that is used all over the world as a pesticide and piscicide. Before establishing its potential and efficiency for these purposes, it is essential to know more about the possible adverse effects that it may cause. The current work aimed to evaluate the mutagenic potential of rotenone using fish from the species Oreochromis niloticus, as well as to help in understanding its action mechanism. Our results showed the mutagenic potential of rotenone evidenced by increased formation of micronuclei and nuclear buds at low doses of exposure. The use of fluorescence in situ hybridisation technique made it possible to measure the aneugenic potential of the substance, probably due to its impairment of mitotic spindle formation.

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.

Evaluation of genotoxicity induced by exposure to antineoplastic drugs in lymphocytes of oncology nurses and pharmacists

The hazards of handling antineoplastic drugs have been raised and discussed in several studies. Introduction of new antineoplastics together with abuse of safety standards have contributed to the exposure risk for personnel who handle these substances. Interactions of antineoplastic drugs with biological structures vary according to the drug(s) and the individual's genetic susceptibility. This study was carried out to evaluate the genome damage induced by exposure to antineoplastic drugs in nurses (n = 20) and pharmacists (n = 18) working in the Oncology Department of Tanta Cancer Center. Thirty subjects matched in age, gender and smoking habit were selected as controls. Both chromosomal aberration analysis and micronucleus assay were used to evaluate genome damage in peripheral blood lymphocytes of the study subjects. The numbers of aberrant lymphocytes, as well as chromosomal aberration and micronuclei frequencies, were significantly increased in exposed personnel in comparison to matched controls. Compared with pharmacists, nurses showed notably higher level of chromosome damage. On the other hand, no significant difference in micronuclei frequency was observed between nurses and pharmacists. Correlation analyses pointed to the influence of age and duration of occupational exposure on the level of chromosome damage among exposed subjects. The results of this study confirmed that handling antineoplastic drugs without appropriate precautions imposed a genotoxic risk for exposed healthcare workers. These results address the need for regular biomonitoring of exposed personnel. In addition, they call attention to the need for proper implementation of intervention measures aiming to eliminate or significantly reduce worker exposure and prevent untoward biological effects.

Biomarkers of occupational exposure do anticancer agents: a minireview

The majority of anticancer agents has in common DNA-damaging properties and affects not only target-cells but also non-tumour cells. Its genotoxicity has been demonstrated in experimental models and in cancer patients treated with chemotherapy. Health care personnel involved in the preparation and administration of chemotherapy is therefore at risk for adverse health effects, since most environmental sampling studies demonstrated that there is widespread contamination of work surfaces and equipments with anticancer drugs. Adherence to safety guidelines and proper use of personal protective equipment are insufficient to prevent significant absorption, as evidenced by the presence of detectable amounts of drugs in urine samples and increased frequency of genotoxicity biomarkers. In this minireview, a critical appraisal of the most important biomarkers used for the evaluation of occupational exposure to anticancer agents as well as a summary of the key findings from several studies published in this field is performed.

Cytomorphological changes in buccal mucosa of patients treated with low-level 1,064-nm laser radiation

The aim of this study was to examine the cytomorphological changes occurring in the buccal mucosa in patients treated with low-level 1,064-nm laser radiation. Seventeen individuals (12 males, five females) 18-24 years of age were included in the study. Low-level 1,064-nm laser radiation was applied to the right buccal mucosa near the premolar region; this therapy was repeated for 10 days. Buccal epithelial cells were collected from the right and left premolar regions of the individuals with a brush before and after therapy. The specimens collected from the left side were measured cytomorphometrically and used for the control group. Student's t test was used for statistical comparison of the values of the buccal epithelial cells collected from individuals; a p value < 0.05 was considered statistically significant. None of the patients showed any adverse reactions to the low-level 1,064-nm laser radiation therapy during application. There was no cytogenetic damage to the therapied or non-therapied regions in the buccal mucosa cells, as determined cytomorphologically. The results suggest that low-level 1,064-nm laser radiation therapy has no genotoxic potential. Within the limitations of this study, it can be concluded that low-level 1,064-nm laser radiation therapy may be used safely in dental treatments.

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.

Antineoplastic Drugs as a Potential Risk Factor in Occupational Settings: Mechanisms of Action at the Cell Level, Genotoxic Effects, and Their Detection Using Different Biomarkers

U članku je prikazana osnovna podjela antineoplastičnih lijekova prema mehanizmima djelovanja na razini stanice. Objašnjeni su mehanizmi genotoksičnosti najvažnijih vrsta lijekova koji se primjenjuju u okviru uobičajenih protokola za liječenje zloćudnih novotvorina. Navedena je važeća klasifikacija antineoplastika prema kancerogenom potencijalu, podaci o mutagenom potencijalu te je prikazana njihova podjela u skladu s anatomsko-terapijsko-kemijskim sustavom klasifikacije. Sustavno su prikazani najvažniji rezultati svjetskih i hrvatskih istraživanja na populacijama radnika izloženih antineoplasticima, provedenih u razdoblju 1980.-2009. s pomoću četiri najčešće primjenjivane metode: analize izmjena sestrinskih kromatida, analize kromosomskih aberacija, mikronukleus-testa i komet-testa. Objašnjena su osnovna načela navedenih metoda te raspravljene njihove prednosti i nedostaci. Biološki pokazatelji daju važne podatke o individualnoj osjetljivosti profesionalno izloženih ispitanika koji mogu poslužiti unaprjeđenju postojećih uvjeta rada i upravljanju rizicima pri izloženosti genotoksičnim agensima. Na osnovi prednosti i nedostataka citogenetičkih metoda zaključeno je da je mikronukleus-test, koji podjednako uspješno dokazuje klastogene i aneugene učinke, jedna od najboljih metoda dostupnih za otkrivanje štetnih djelovanja antineoplastičnih lijekova koji su u aktivnoj primjeni.

Evaluation of a suitable DNA damage biomarker for human biomonitoring of exposed workers

The objective of this study was to identify a sensitive and noninvasive biomarker of early genotoxic effects, for health risk assessment of workers exposed to mixtures of low doses of xenobiotics. We studied 30 workers exposed to antineoplastic drugs, 57 workers exposed to different mixtures of polycyclic aromatic hydrocarbons (PAHs) (41 airport workers and 16 paving workers) and 76 controls. Comet and micronucleus (MN) tests were performed on lymphocytes and exfoliated buccal cells. The MN assay on lymphocytes did not show significant differences between exposed and controls, while the MN assay on exfoliated buccal cells showed higher values in workers exposed to antineoplastics as compared with controls (0.85 vs. 0.48, P = 0.042). The comet assay on lymphocytes showed a higher comet percentage value (18.11 vs. 11.24 in controls, P = 0.001) and mean tail moment (TM) value (21.84 vs. 16.72 in controls, P = 0.003) in individuals exposed to PAHs as compared with controls; no significant differences were found in exposed to antineoplastics. The comet assay on exfoliated buccal cells did not show significant differences between exposed and control groups for comet percentages, whereas the TM value was higher in workers exposed to PAHs (55.1 vs. 32.31 for controls, P < 0.001). These results show that exfoliated buccal cells, obtained by a noninvasive procedure, represent robust target cells to assess the occupational exposure to inhalable mixture of chemicals at low doses. The comet assay seems to be suitable to promptly evaluate the genotoxic effects of PAHs mixtures that also contain volatile substances. The MN test is suitable to evaluate the effects of antineoplastics. Inc.

Comparison of chromosomal aberrations frequency and polymorphism of GSTs genes in workers occupationally exposed to cytostatics or anaesthetics

Authors compared the incidence of chromosomal aberrations (CAs) of workers occupationally exposed to cytostatics (group EXP1) or anaesthetics (group EXP2) in relationship to polymorphism of GSTM1, GSTP1 and GSTT1 genes. The cytogenetic analysis for chromosomal aberrations frequency and for polymorphisms of genes the PCR and PCR-RFLP method were used. Statistically higher frequency of total CAs was detected in both exposed groups: group EXP1 1.90±1.34%; Mann-Whitney U-test, p=0.001; group EXP2 2.53±1.46%, p=0.0008) as compared to control (1.26±0.93%). In group EXP2 was detected statistically higher frequency of aberrations CSA-type as compared to CTA-type. In xenobiotic metabolizing genes for GST higher frequency of total CAs and constituent types chromatid-type aberrations (CTAs) and chromosome-type aberrations (CSAs) of genes GSTM1 and GSTT1 with null genotype was detected. Statistically significant difference was detected only in CSA-type of aberrations in GSTT1 gene. In gene GSTP1 was not detected any difference in frequency of aberrations in presence of the variant allele. Presented results point out importance of individual susceptibility in evaluation of genotoxic agents of anaesthetics or cytostatics.

The genotoxic risk in health care workers occupationally exposed to cytotoxic drugs--a comprehensive evaluation by the SCE assay

Present study aimed at an integral assessment of sister chromatid exchange (SCE) frequencies in the health care workers occupationally exposed to cytostatics. The results of 500 individual analyses were evaluated. Drug handling practice was investigated in parallel and the results showed that cytostatics are mostly prepared outside hospital pharmacy (98%) and mainly handled by nurses (96%). Mean frequency of SCE was 5.63 +/- 2.28, while HFC represented 9.65% of the cells analysed. Both values were higher compared to previously established control values for Croatian population. The duration of exposure, profession, age, gender, smoking habit, medical exposures, and simultaneous exposure to other occupational mutagens significantly contributed to SCE and HFC values. The usefulness both biomarkers in the assessment of cytogenetic damage is confirmed. Since current practice in Croatian hospitals does not include regular monitoring of workplaces, to ensure maximal occupational safety, a surveillance on exposed health care workers, including periodic biomonitoring, is recommended.

Effect of occupational exposure to cytostatics and nucleotide excision repair polymorphism on chromosomal aberrations frequency

Authors evaluated the incidence of total chromosomal aberrations (CA) and their types – chromatid-type (CTA) and chromosome-type (CSA) in peripheral blood lymphocytes from 72 oncologic unit's workers occupationally exposed to cytostatics in relationship to polymorphisms of DNA repair genes XPD, XPG and XPC. The cytogenetic analysis was used for determination of chromosomal aberrations frequency and PCR-RFLP method for polymorphisms of genes. Statistically higher frequency of total CA was detected in exposed group as compared to control (1.90±1.34% vs. 1.26±0.93%; Mann-Whitney U-test, p=0.001). There was not detected any difference between CTA and CSA (0.92±1.04% vs. 0.98±1.17%). Similarly, in genes XPD exon 23 and XPC exon 15 wasn't detected any difference neither in total chromosomal aberrations nor in CTA and CSA types. Statistically significant decrease of total chromosomal aberrations and CTA-type with presence of variant allele C was detected in gene XPG exon 15. Authors pointed out the importance of individual susceptibility factors in evaluation of effects of genotoxic agents, in that event, when the concentration does not meet the occupational exposure limit.

Genotoxic effects of waterpipe smoking on the buccal mucosa cells

Waterpipe smoking is popular in many parts of the world. Micronuclei (MN) evaluation in the exfoliated oral cells of smokers is a non-invasive technique for evaluation of possible tobacco harm. We aimed to assess whether MN levels are higher in waterpipe smokers than in never smokers. We examined oral smears of 128 adult male waterpipe smokers and 78 males who never smoked tobacco in rural Egypt. The total number of MN per 1000 cells per subject, and the number of MN-containing cells per individual were compared. We observed a higher level of total MN in waterpipe smokers (10 +/- 4) than in never smokers (4 +/- 2, p < 0.001). A similar difference was found for the mean number of affected cells per individual (8 +/- 3 vs. 4 +/- 1.62, p < 0.001). MN levels were not significantly dose related. This study is among the first to assess the association between waterpipe smoking and a cytogenetic measure of tobacco harm. The twofold increase in MN level is consistent with previous reports of MN in cigarette smokers. More research is needed to determine if such MN levels are predictive of future health consequences.