Antineoplastic drug occupational exposure: a new integrated approach to evaluate exposure and early genotoxic and cytotoxic effects by no-invasive Buccal Micronucleus Cytome Assay biomarker

Genotoxic effects in island populations of Cartagena de Indias, Colombia due to environmental exposure to mercury and cadmium

Background

Contamination of Cartagena Bay, Colombia with heavy metals such as mercury (Hg) and cadmium (Cd) presents a major environmental and public health concern, particularly for human communities residing on nearby islands and coastal areas. These populations face enhanced exposure risks owing to their traditional fishing practices and continuous interactions with polluted marine environments. This study aimed to evaluate the genotoxic effects of environmental exposure to Hg and Cd in populations from the island zone of the Cartagena district, Bolívar.

Methods

Ninety-four individuals from the four island communities (study group) and 30 individuals from the urban area of Cartagena (control group) participated in this study. The blood samples were collected to measure total mercury (T-Hg) and Cd concentrations, and a Buccal Micronucleus Cytome (BMCyt) assay was used to evaluate exposure effects.

Results

Cadmiun levels in the blood of the study group were within the normal range and comparable to those of the control group (p > 0.05). However, the study group exhibited significantly higher T-Hg levels (7.34 μg/L) compared to the control group (2.01 μg/L), surpassing the accepted limit. Moreover, the study group showed a higher incidence of DNA damage and cell death biomarkers (p < 0.05). Additionally, significant correlations were observed between total blood Hg levels and the frequencies of micronuclei, karyorrhexis, and karyolysis.

Conclusion

These results suggest that island populations of Cartagena are exposed to high levels of Hg and exhibit genotoxic damage, indicating a problem that must be addressed.

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.

From a Chemotherapeutic Drug to a High-Performance Nanocatalyst: A Fast Colorimetric Test for Cisplatin Detection at ppb Level

A rapid point-of-care method for the colorimetric detection of cisplatin was developed, exploiting the efficient conversion of the chemotherapeutic drug into a high-performance nanocatalyst with peroxidase enzyme mimics. This assay provides high specificity and ppb-detection sensitivity with the naked eye or a smartphone-based readout, outperforming many standard laboratory-based techniques. The nanocatalyst-enabled colorimetric assay can be integrated with machine-learning methods, providing accurate quantitative measurements. Such a combined approach opens interesting perspectives for the on-site monitoring of both chemotherapeutic patients to achieve optimal treatments and healthcare workers to prevent their unsafe exposure.

Impact of low- and high-risk operators handling irinotecan on the blood contamination of health care workers in oncology day care units

INTRODUCTION

Health care workers handling antineoplastic drugs (ADs) are at risk of mutagenicity and adverse reproductive effects. Despite protective equipment and AD handling guidelines, AD levels are still detected in caregivers in oncology units. This study attempted to assess blood contamination by irinotecan and its metabolites in all health care workers in oncology day hospital units according to activities specific to each employment category.

METHODS

The study was performed at two different hospitals: a university hospital and a comprehensive cancer centre. Forty-four participants were categorized according to their daily activity as a high-risk operator (29 nurses/ward aides and 5 cleaning staff) and a low-risk operator (7 doctors and 3 secretaries). The collected blood samples were subjected to UHPLC-MS/MS. The plasma and red blood cell (RBC) levels of irinotecan and its metabolites (SN-38; APC) were determined using a validated analytical method detection test.

RESULTS

Two hundred sixty-four assay results were collected (132 plasma results and 132 RBC results). The comparison between low- and high-risk operator-contaminated workers was not significant (18.33% positive results in low-risk operators vs. 25.98% positive results in high-risk operators; P = 0.22). This homogeneity showed overall contamination within the unit. Positive results were obtained in 21.43% of physicians, 11.11% of secretaries, 25.86% of nurses/ward aides and 26.67% of cleaning staff. These results could be explained by the lack or failure of personal and collective protective equipment. A lack of protection and inadequate decontamination procedures can result in surface contamination.

CONCLUSIONS

This study evaluated blood contamination with irinotecan and its metabolites in health care workers from day hospital care units. Among the 24.24% of contaminations observed in care units, the difference between low- and high-risk operator contamination was not significant (P = 0.22). The impact on blood contamination found is the same between low- and high-risk caregivers. This implies that the protective precautions associated with the handling of anticancer drugs must therefore be followed by all staff, including those believed to be at low risk of exposure.

Nurses' internal contamination by antineoplastic drugs in hospital centers: a cross-sectional descriptive study

OBJECTIVE

The aim of this study was to assess internal antineoplastic drugs (ADs) contamination in the nursing staff in French hospital centers, using highly sensitive analytical methods.

METHODS

This cross-sectional study included nurses practicing in care departments where at least one of the five ADs studied was handled (5-fluorouracil, cyclophosphamide, doxorubicin, ifosfamide, methotrexate). The nurses study participation lasted 24 h including collection of three urine samples and one self-questionnaire. All urine samples were assayed by ultra-high-performance liquid chromatography-tandem mass spectrometry methods with very low value of the lower limit of quantification (LLOQ).

RESULTS

74 nurses were included, 222 urine samples and 74 self-questionnaires were collected; 1092 urine assays were performed. The percentage of nurses with internal AD contamination was 60.8% and low levels of urinary concentrations were measured. Regarding nurses with internal contamination (n = 45), 42.2% presented internal contamination by methotrexate, 37.8% by cyclophosphamide, 33.3% by ifosfamide, 17.8% by 5-fluorouracil metabolite and 6.7% by doxorubicine. Among the positive assays, 17.9% (n = 26/145) were not explained by exposure data from the self-questionnaire but this could be due to the skin contact of nurses with contaminated work surfaces.

CONCLUSIONS

This study reported high percentage of nurses with internal ADs contamination. The low LLOQ values of the used analytical methods, allowed the detection of ADs that would not have been detected with the current published methods: the percentage of contamination would have been 17.6% instead of the 60.8% reported here. Pending toxicological reference values, urine ADs concentrations should be reduced as low as reasonably achievable (ALARA principle).

Biomonitoring of workers employed in a titanium dioxide production plant: Use of buccal micronucleus cytome assay as noninvasive biomarker to evaluate genotoxic and cytotoxic effects

We aimed to evaluate whether TiO₂ production process induces genotoxic and cytotoxic effects on the first target organ of inhalable particles by a sensitive and noninvasive biomarker of effect. Final aim was to find a useful and suitable tool to assess and manage the risk of TiO₂ occupational exposure. We enrolled 40 workers employed in TiO₂ production, 5 office workers, and 18 external controls. Buccal micronucleus cytome assay (BMCyt assay) was applied because it allows to evaluate micronucleus (MN), nuclear buds (NB), and broken eggs (BE) indicating the presence of chromosomal instability and gene amplification and binucleated cells (BIN), karyolytic cells (KL), and condensed chromatin (CC) indicating cytokinesis defect or arrest, cell death and apoptosis respectively. We characterized the exposure measuring inhalable and respirable particles by personal monitoring. BMCyt-assay showed in exposed workers compared with external controls a higher value of MN frequency (2.57 vs. 0.05‰, p < .001) and MN positivity, evaluated as percentage of subjects with MN frequency higher than a 1.5‰ cut-off value (52.5 vs. 0%). We also found in exposed workers higher frequency of BE + NB (2.41 vs. 0.22‰, p = .002), BIN (9.45 vs. 8.44‰, p = .047) and CC (1.80 vs. 0.21, p = .001) than in controls. Moreover, we found a relationship between personal monitoring results and presence of MN and other cellular anomalies. This study demonstrates induction of genotoxic and cytotoxic effects on buccal cells of workers involved in TiO₂ production, suggesting the suitability of BMCyt assay as tool for risk assessment and management of TiO₂ exposure.

Occupational exposure to graphene and silica nanoparticles. Part II: pilot study to identify a panel of sensitive biomarkers of genotoxic, oxidative and inflammatory effects on suitable biological matrices

The available biomonitoring studies on workers producing/handling nanomaterials (NMs) focused on potential effects on respiratory, immune and cardio-vascular system. Aim of this study was to identify a panel of sensitive biomarkers and suitable biological matrices to evaluate particularly genotoxic and oxidative effects induced on workers unintentionally exposed to graphene or silica nanoparticles during the production process. These nanomaterials have been chosen for 'NanoKey' project, integrating the workplace exposure assessment (reported in part I) with the biomonitoring of exposed workers reported in the present work. Simultaneously to workplace exposure characterization, we monitored the workers using: Buccal Micronucleus Cytome (BMCyt) assay, fpg-comet test (lymphocytes), oxidized DNA bases 8-oxoGua, 8-oxoGuo and 8-oxodGuo measurements (urine), analysis of oxidative stress biomarkers in exhaled breath condensate (EBC), FENO measurement and cytokines release detection (serum). Since buccal cells are among the main targets of NM occupational exposure, particular attention was posed to the BMCyt assay that represents a noninvasive assay. This pilot study, performed on 12 workers vs.11 controls, demonstrates that BMCyt and fpg-comet assays are the most sensitive biomarkers of early, still reparable, genotoxic and oxidative effects. The findings suggest that these biomarkers could represent useful tools for the biomonitoring of workers exposed to nanoparticles, but they need to be confirmed on a high number of subjects. However, such biomarkers don't discriminate the effects of NM from those due to other chemicals used in the NM production process. Therefore, they could be suitable for the biomonitoring of workers exposed to complex scenario, including nanoparticles exposure.