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

Impact of Educational Intervention on Compliance of Health Care Workers Towards Chemotherapy Handling Guidelines

Background

Chemotherapy safety guidelines have been enacted to minimize their side effects on healthcare providers when handling medications. The aim of this study is to assess the impact of an educational intervention on healthcare workers' compliance with chemotherapy safety guidelines.

Methods

In this study, we used a quasi-experimental, pre-post testing design. It was conducted in the Oncology center at King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia. All healthcare workers involved in the preparation and administration of chemotherapy medications in KSUMC were invited. We evaluated Educational intervention to ensure the compliance of healthcare workers with standard safety guidelines through a questionnaire with 29 questions in total.

Results

Fifty-two participants were eligible in this study. Overall, the score for mean compliance with workplace guidelines among the participants increased from 17.62∓0.78 to 18.17∓0.80 out of 19. Multiple liner regression indicates that there are no variables among the included variables predicting a change in post-intervention.

Conclusion

This study indicates that educational intervention is the only effect of compliance in the included sample. Education safety training could improve healthcare workers' knowledge and consequently improve their compliance in the preparation and administration of chemotherapy medication.

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.

The meta-analysis of sister chromatid exchange as a biomarker in healthcare workers with occupational exposure to antineoplastic drugs

BACKGROUND

Sister chromatid exchange (SCE) can be used to identify early occupational health status in health care workers. Our aim is to comprehensively assess the relationship between long-term exposure to antineoplastic drugs (ADs) and SCE in health care workers via meta-analysis.

METHODS

Five databases were systematically searched for relevant articles published from inception to November 30, 2022. Literature data are expressed as mean difference and 95% confidence intervals (CI) or relative risk and 95% CI. For I2 > 50% trials, random effect model is used for statistical analysis, otherwise fixed effect model is used. This review was registered in the International Prospective Register of Systematic Reviews (identifier CRD42023399914).

RESULTS

Fourteen studies were included in this study. Results showed the level of SCE in healthcare workers exposed to ADs was significantly higher than in controls. The mean difference of the SCE trial was 0.53 (95% CI: 0.10-0.95, P = .01) under a random-effects model.

CONCLUSIONS

The findings suggested a significant correlation between occupational exposure to ADs in health care workers and SCE, requiring the attention of health care workers in general.

Biological response to the continuous occupational exposure to antineoplastic drugs and radionuclides

PURPOSE

Antineoplastic drugs and radioiodine are recognized occupational risk factors affecting the genetic material of exposed persons. To assess cytogenetic damage and evaluate the presence of chromosomal instability during occupational exposure, a biomonitoring study was performed using a chromosomal aberration assay and a cytokinesis-block micronucleus (CBMN) test.

MATERIALS AND METHODS

Blood samples from 314 healthy donors divided into 3 groups (control, exposed to antineoplastic drugs and exposed to radioiodine) were collected and cytogenetically analyzed.

RESULTS

There was an increase in almost all analyzed parameters registered in the exposed persons. Chromatid breaks were higher in the subjects exposed to antineoplastic drugs, while dicentrics and premature centromere division (PCD) parameters were higher in nuclear medicine workers. The total number of micronuclei was higher in both groups of the exposed. The correlation analysis indicated the association of dicentrics, acentrics, chromosome and chromatid break with PCDs in both groups of the exposed, and micronuclei and nucleoplasmic bridges with PCDs in the subjects exposed to radioiodine. The discriminant analysis marked off PCD1-5 as the best predictor of exposure. Age, sex, sampling season and duration of exposure significantly influenced the analyzed parameters, while smoking habits did not show any influence.

CONCLUSION

Based on the observed results, premature centromere division can be considered a valuable parameter of genotoxic risk for individuals occupationally exposed to low doses of ionizing radiation.

The Factors That Influence Chemotherapy Exposure Among Nurses: An Integrative Review

BACKGROUND

Exposure to chemotherapy is an occupational hazard predisposing nurses to severe health effects. The purpose of this integrative review was to identify the recent literature describing the risk factors for occupational exposure to chemotherapy among nurses.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology was employed to conduct the review. The databases searched were Scopus, PubMed, and CINAHL using the search terms "chemotherapy," "drugs," "exposure," and "nurses." Included articles were published between January 2010 and February 2022, published in peer-reviewed journals for research conducted in the United States, and written in English language. Excluded articles were studies that did not involve nurses in their samples. Review articles, books, theses, and dissertations were excluded as well. The Johns Hopkins Nursing Evidence-Based Practice Model was used to assess the level of evidence from the reviewed studies.

FINDINGS

Fourteen studies were included in this review. Ten studies were rated on Evidence Level III, two on Evidence Level II, one on Evidence Level I, and one on Evidence Level V. The main risk factors for occupational exposure were nurses' knowledge of chemotherapy handling guidelines, nurses' adherence to using the personal protective equipment, nurses' health beliefs regarding chemotherapy exposure, and workplace-related factors such as workload and managerial support.

CONCLUSION

Addressing the identified risk factors would protect nurses from chemotherapy exposure. More research on nurses' health beliefs regarding chemotherapy exposure and the cues to adhere to chemotherapy handling guidelines in the work environment is needed.

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.

The meta-analysis of cytogenetic biomarkers as an assessment of occupational risk for healthcare workers exposed to antineoplastic drugs

OBJECTIVE

Antineoplastic drugs (ADs) are widely used in clinical practice and have been demonstrated to be effective in treating malignant tumors. However, they carry a risk of cytogenotoxicity for healthcare workers. Studies have reported that genotoxic biomarkers can be applied to assess the occupational health status of healthcare workers at an early stage, but results of different studies are variable. The objectives of the review were examine the association between long-term exposure to ADs and cytogenetic damage to healthcare workers.

METHODS

We systematically reviewed studies between 2005 and 2021 using PubMed, Embase and Web of Science databases that used cytogenetic biomarkers to assess occupational exposure to ADs in healthcare workers. We used RevMan5.4 to analyze the tail length parameters of the DNA, frequency of the chromosomal aberrations, sister chromatid exchanges and micronuclei. A total of 16 studies were included in our study. The studies evaluate the quality of the literature through the Agency for Healthcare Research and Quality.

RESULTS

The results revealed that under the random-effects model, the estimated standard deviation was 2.37 (95% confidence interval [CI] 0.92-3.81, P = 0.001) for the tail length parameters of the DNA, 1.48 (95% CI 0.71-2.25, P = 0.0002) for the frequency of chromosomal aberrations, 1.74 (95% CI 0.49-2.99, P = 0.006) for the frequency of sister chromatid exchanges and 1.64 (95% CI 0.83-2.45, P < 0.0001) for the frequency of micronuclei.

CONCLUSIONS

The results indicate that there is a significant association between occupational exposure to ADs and cytogenetic damage, to which healthcare workers should be alerted.

Exposure To Cytotoxic Drugs Threatens The Health Of Staff In Oncology Wards

Background — Cancer is one of the leading causes of death worldwide. Using cytotoxic drugs for cancer treatment is increased. The hazardous effects of occupational exposure to cytotoxic drugs are challenging. Objective — This study aimed to compare the frequency of adverse effects and using personal protective equipment (PPE) between the staff of oncology wards and other hospital wards staff in Iran. Methods — A cross-sectional study with a control group was conducted on female staff members in educational hospitals, selected through convenience sampling. A data collection form was designed for this study. It includes demographic data, acute complications (allergic and neurologic reactions), chronic complications (infertility, menstrual disorders, malignancy, and congenital malformations), and use of PPE. Data analysis was performed using SPSS software through Chi-square and Mann-Whitney tests. Results — The frequencies of chronic complications were not statistically different between the two groups. The frequency of itching (P=0.001), hair loss (P=0.003), itchy eyes (P=0.001), watery eyes (P=0.001), runny nose (P=0.003), headache (P=0.001), vertigo (P=0.007), and nausea (P=0.008) were significantly higher in oncology wards nurses. Among different PPE, only the frequency of using the mask (P= 0.001), and glasses (P=0.027) were significantly higher in the staff of oncology wards. Conclusion — Despite the frequency of acute complications of exposure to cytotoxic drugs, oncology staff does not fully adhere to the standard precautions. Providing effective training and emphasis on implementing accreditation laws can improve the existing situation.

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.

The Key Characteristics of Carcinogens: Relationship to the Hallmarks of Cancer, Relevant Biomarkers, and Assays to Measure Them

The key characteristics (KC) of human carcinogens provide a uniform approach to evaluating mechanistic evidence in cancer hazard identification. Refinements to the approach were requested by organizations and individuals applying the KCs. We assembled an expert committee with knowledge of carcinogenesis and experience in applying the KCs in cancer hazard identification. We leveraged this expertise and examined the literature to more clearly describe each KC, identify current and emerging assays and in vivo biomarkers that can be used to measure them, and make recommendations for future assay development. We found that the KCs are clearly distinct from the Hallmarks of Cancer, that interrelationships among the KCs can be leveraged to strengthen the KC approach (and an understanding of environmental carcinogenesis), and that the KC approach is applicable to the systematic evaluation of a broad range of potential cancer hazards in vivo and in vitro We identified gaps in coverage of the KCs by current assays. Future efforts should expand the breadth, specificity, and sensitivity of validated assays and biomarkers that can measure the 10 KCs. Refinement of the KC approach will enhance and accelerate carcinogen identification, a first step in cancer prevention.See all articles in this CEBP Focus section, "Environmental Carcinogenesis: Pathways to Prevention."

Knowledge and associated factors towards cytotoxic drug handling among University of Gondar Comprehensive Specialized Hospital health professionals, institutional-based cross-sectional study

BACKGROUND

Currently, cancer is among the leading causes of morbidity and mortality in the world. Exposure to CDs may occur during drug preparation and mixing, during drug administration, during transport, and cleaning spills and waste disposal. Healthcare workers who prepare or administer antineoplastic drugs, or who work in areas where these drugs are used, can be exposed to these agents. This also affects the public around the exposed area if appropriate disposal system is not known. Several studies reported increased risks of leukemia and breast cancer among nurses handling CDs and not following safety guidelines. Because of the absence of studies in Ethiopia, the current study was conducted to determine the knowledge level of cytotoxic drug handling and associated factors among health professionals in the University of Gondar Comprehensive Specialized Hospital.

METHODS

The institutional-based cross-sectional study was conducted from June to August 2019. Epi info 7.1 was used for data entry and then exported into SPSS version 20 for computing, recording, and statistical analysis. Logistic regression was used to explain the relationship with independent variables.

RESULTS

Four hundred and twelve health professionals participated in the study with 53.4% males. The participants' mean age was 29.9 (± 5.43) years ranging from 20-60. Two hundred and twenty-three (54.1%) health professionals heard about cytotoxic drugs, and 52.7% (95% UI 47.8-57.8%) had good knowledge of cytotoxic drug handling. Being male sex (AOR = 1.84, 95% CI (1.13-3.00)), age of 29-31 (AOR = 1.99, 95% CI (1.03-3.84)), hearing information about cytotoxic drug handling (AOR = 2.53, 95% CI (1.43-4.47)), ever attended training on cytotoxic drug handling (AOR = 3.15, 95% CI (1.13-8.79)), ever taking courses related to cytotoxic drugs (AOR = 2.03, 95% CI (1.15-3.59)), and good practice (AOR = 3.24, 95% CI (1.95-5.37)) were significantly associated with knowledge towards cytotoxic drug handling. It is therefore imperative to train health professionals and to incorporate CDs handling related course contents while revising curricula to raise the knowledge of health professionals about proper cytotoxic drug handling.

CONCLUSION

Above half of the study participants scored higher than the median of the cytotoxic drug handling knowledge questions. Sex, age, information about cytotoxic drug handling, training, taking courses related to cytotoxic drugs, and good practice were significantly associated with knowledge towards cytotoxic drugs handling.

Genotoxicity assessment of a selected cytostatic drug mixture in human lymphocytes: A study based on concentrations relevant for occupational exposure

Cytostatic drugs are highly cytotoxic agents used in cancer treatment and although their benefit is unquestionable, they have been recognized as hazardous to healthcare professionals in occupational settings. In a working environment, simultaneous exposure to cytostatics may occur creating a higher risk than that of a single substance. Hence, the present study evaluated the combined cyto/genotoxicity of a mixture of selected cytostatics with different mechanisms of action (MoA; 5-fluorouracil, cyclophosphamide and paclitaxel) towards human lymphocytes in vitro at a concentration range relevant for occupational as well as environmental exposure. The results suggest that the selected cytostatic drug mixture is potentially cyto/genotoxic and that it can induce cell and genome damage even at low concentrations. This indicates not only that such mixture may pose a risk to cell and genome integrity, but also that single compound toxicity data are not sufficient for the prediction of toxicity in a complex working environment. The presence of drugs in different amounts and with different MoA suggests the need to study the relationship between the presence of genotoxic components in the mixture and the resulting effects, taking into account the MoA of each component by itself. Therefore, this study provides new data sets necessary for scientifically-based risk assessments of cytostatic drug mixtures in occupational as well as environmental settings.

Meta-analysis of chromosomal aberrations as a biomarker of exposure in healthcare workers occupationally exposed to antineoplastic drugs

Many antineoplastic drugs used to treat cancer, particularly alkylating agents and topoisomerase inhibitors, are known to induce genetic damage in patients. Elevated levels of chromosomal aberrations, micronuclei, and DNA damage have been documented in cancer patients. Elevations in these same biomarkers of genetic damage have been reported in numerous studies of healthcare workers, such as nurses and pharmacists, who routinely handle these drugs, but results vary across studies. To obtain an overall assessment of the exposure effect, we performed a meta-analysis on data obtained from peer-reviewed publications reporting chromosomal aberration levels in healthcare workers exposed to antineoplastic drugs. A literature search identified 39 studies reporting on occupational exposure to antineoplastic drugs and measurement of chromosomal aberrations in healthcare workers. After applying strict inclusion criteria for data quality and presentation, data from 17 studies included in 16 publications underwent meta-analysis using Hedges' bias-corrected g and a random-effects model. Results showed the level of chromosomal aberrations in healthcare workers exposed to antineoplastic drugs was significantly higher than in controls. The standardized mean differences (difference of means divided by within sd) from all studies were pooled, yielding a value 1.006 (unitless) with p<0.001. Thus, in addition to the documented genotoxic effects of antineoplastic drugs in cancer patients, this meta-analysis confirmed a significant association between occupational exposure to antineoplastics during the course of a normal work day and increases in chromosomal aberrations in healthcare workers. Based on the studies reviewed, we were unable to accurately assess whether appropriate use of protective measures might reduce the incidence of genetic damage in healthcare workers. However, given the potential for increased cancer risk linked to increases in chromosomal aberrations, the results of this study support the need to limit occupational exposure of healthcare workers to antineoplastic drugs as much as possible.

Nurse Adherence to Safe-Handling Practices: Observation Versus Self-Assessment

BACKGROUND

Chemotherapy medications place nurses at risk for occupational exposure, a primary nursing safety concern. No literature was available on adherence to following chemotherapy handling practices and nurses' perceptions of safe-handling practices.

OBJECTIVES

The aims of the pilot study were to examine actual and subjective ambulatory oncology nurse adherence to chemotherapy safe-handling guideline recommendations that prevent chemotherapy exposure.

METHODS

A prospective, comparative mixed-methods study was used to compare objective and subjective nurse behaviors of expected safe chemotherapy handling-specifically, micro-ethnography and questionnaires. Fisher's exact test was used to assess differences in the rates of observations and questionnaire responses.

FINDINGS

Twenty-two cases of chemotherapy handling were observed, and 12 of 33 nurses completed self-assessments. Of observed practices, nurses completed three behaviors 100% of the time (disposing of gloves in a chemotherapy-approved container after initiating chemotherapy, discarding the chemotherapy bag and tubing after disconnecting chemotherapy infusions, and washing hands after chemotherapy was administered). When objective and subjective behavior adherence were compared, three behaviors were carried out with greater frequency than what nurses perceived on questionnaires (double gloving and gowning when disconnecting chemotherapy and properly discarding chemotherapy). Two behaviors were carried out with less frequency than nurses provided on questionnaires (double gloving and protecting work surfaces during administration).

Study of the stability of 26 cytostatic drugs and metabolites in wastewater under different conditions

The stability of 26 cytostatic drugs (21 parent compounds and 5 metabolites) in wastewater was studied using liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS). Wastewater aliquots were spiked with the target compounds at 1000μg L(-1) and stored in the dark under different temperature (-20, 4 and 25°C) and pH (acid and neutral) conditions for different periods of time (up to 3 months). The influence of these factors (temperature, pH and time) on the stability of the compounds was evaluated through an experimental design. The most negative factor was the time of storage, but temperature also exerted a very important influence. Acidification of the samples is a good option for some cytostatics (e.g., temozolomide, tamoxifen and its metabolites, and chlorambucil) but it may have a negative effect on others (e.g. ifosfamide). The design also showed correlations between factors indicating that an increase of the storage time is more relevant at high temperatures, while an increase of the temperature is more detrimental in non-acidified samples. After 3 months at -20°C, all compounds with the exception of temozolomide, vinorelbine, imatinib and erlotinib presented recoveries below 80%. The most unstable compounds were oxaliplatin, 5-(3-N-methyltriazen-1-yl)-imidazole-4-carboxamide and chlorambucil. To the authors' knowledge, the stability data reported in the present study is the first ever published for most of the target compounds in wastewater. The results obtained point out storage at -20°C from collection to analysis as the best storage option.

In vitro tests aiding ecological risk assessment of ciprofloxacin, tamoxifen and cyclophosphamide in range of concentrations released in hospital wastewater and surface water

Ciprofloxacin (CIP), tamoxifen (TAM) and cyclophosphamide (CP) which are often used in anticancer treatment are released in hospital effluent and into the environment. Although the concentrations are low (from ng/L to μg/L), no data exist concerning their ecotoxicological impact. In this study two biomarkers of early effect were performed on hepatic cells (HepG2): cell viability and genotoxicity (DNA breaks) using cell proliferative assay and comet assay, respectively. These data were compared with two standardized ecotoxicological tests: algaltoxkit F™ and microtox®. Cells were exposed to an increasing amount of an individual drug or in a mixture for 24, 48 or 72h. The time-exposure of bacteria and algae ranged between 5 and 30min and 72h, respectively. A non-monotonic dose-response on cell viability was observed when HepG2 cells were exposed to TAM alone or in the presence of CIP. The same scheme was observed with microtox® when the bacteria were exposed to the mixtures. On the other side, an individual drug does not induce any DNA breaks on hepatic cells, whereas a mixture leads to a dose dependent increase of DNA breaks. Similarly a positive response was observed with algaltoxkit F™ only with mixtures. Synergistic effects observed when drugs are in a mixture highlight the importance of investigating the ecotoxicological effects of contaminants at low concentrations and in mixtures.

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.

Removal of cytostatic drugs from aquatic environment: a review

Cytostatic drugs have been widely used for chemotherapy for decades. However, many of them have been categorized as carcinogenic, mutagenic and teratogenic compounds, triggering widespread concerns about their occupational exposure and ecotoxicological risks to the environment. This review focuses on trace presence, fate and ecotoxicity of various cytostatic compounds in the environment, with an emphasis on the major sources contributing to their environmental concentrations. Past records have documented findings mainly on hospital effluents though little effort has been directed to household discharges. There is also a lack in physico-chemical data for forecasting the chemodynamics of cytostatics in natural waters along with its human metabolites and environmental transformation products. In this light, obtaining comprehensive ecotoxicity data is becoming pressingly crucial to determine their actual impacts on the ecosystem. Literature review also reveals urinary excretion as a major contributor to various cytostatic residues appeared in the water cycle. As such, engaging urine source-separation as a part of control strategy holds a rosy prospect of addressing the "emerging" contamination issue. State-of-the-art treatment technologies should be incorporated to further remove cytostatic residues from the source-separating urine stream. The benefits, limitations and trends of development in this domain are covered for membrane bio-reactor, reverse/forward osmosis and advanced oxidation processes. Despite the respective seeming advantages of source separation and treatment technology, a combined strategy may cost-effectively prevent the cytostatic residues from seeping into the environment. However, the combination calls for further evaluation on the associated technological, social-economic and administrative issues at hand.

5-Fluorouracil induces apoptosis in rat cardiocytes through intracellular oxidative stress

Background

Cardiotoxicity is a major complication of anticancer drugs, including anthracyclines and 5-fluorouracil(5-FU) and it can have detrimental effects both in patients and workers involved in the preparation of chemotherapy.

Methods

Specifically, we have assessed the effects of increasing concentrations of 5-FU and doxorubicin (DOXO) on proliferation of H9c2 rat cardiocytes and HT-29 human colon adenocarcinoma cells by MTT assay. Cells were treated for 24, 48 and 72 h with different concentrations of the two drugs alone or with 5-FU in combination with 10^-4 M of levofolene (LF).

Results

5-FU induced a time- and dose-dependent growth inhibition in both cell lines. The 50% growth inhibition (IC:50) was reached at 72 h with concentrations of 4 μM and 400 μM on HT-29 and H9c2, respectively. The addition of LF to 5-FU enhanced this effect. On the other hand, the IC:50 of DOXO was reached at 72 h with concentrations of 0.118 μM on H9c2 and of 0.31 μM for HT-29. We have evaluated the cell death mechanism induced by 50% growth inhibitory concentrations of 5-FU or DOXO in cardiocytes and colon cancer cells. We have found that the treatment with 400 μM 5-FU induced apoptosis in 32% of H9c2 cells. This effect was increased by the addition of LF to 5-FU (38% of apoptotic cells). Apoptosis occurred in only about 10% of HT-29 cells treated with either 5-FU or 5-FU and LF in combination. DOXO induced poor effects on apoptosis of both H9c2 and HT-29 cells (5–7% apoptotic cells, respectively). The apoptosis induced by 5-FU and LF in cardiocytes was paralleled by the activation of caspases 3, 9 and 7 and by the intracellular increase of O²⁻ levels.

Conclusions

These results suggest that cardiotoxic mechanism of chemotherapy agents are different and this disclose a new scenario for prevention of this complication.