Evaluation of Micronucleus in Exfoliated Buccal Epithelial Cells Using Liquid-based Cytology Preparation in Petrol Station Workers

Is micronucleus assay in oral cells suitable biomarker for evaluating the risk of carcinogenesis in gas station attendants? A systematic review

This study aimed to evaluate all studies which used the micronucleus assay using oral cells in the attempt to understand whether such technique is efficient in evaluating genotoxicity in gas station attendants. Full manuscripts from 16 studies were carefully selected by the authors. Our results demonstrate that continuous exposure to derivatives of petroleum may lead to genotoxic effects since all studies demonstrated positive findings (16 out of 16) and 11 of them had a strong or moderate final rating. In summary, our results reveal that gas station attendants are occupationally exposed to genotoxic agents and that the micronucleus assay in oral mucosa is indeed an effective method to evaluate genotoxicity in this specific case. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods.

Artisanal Gem Mining in Brazil: A Source of Genotoxicity and Exposure to Toxic Elements

Environmental and occupational exposure to toxic metals has led many people around the world to have serious health problems. Mining activities contribute to an increased risk of exposure to these elements. In this work, a study of environmental biomonitoring and routes of exposure to toxic metals in a region of artisanal mining was performed. This study was carried out in the district of Taquaral de Minas, located in the Jequitinhonha Valley in the state of Minas Gerais. The valley is one of the wealthiest and highest gem-producing areas in Brazil. Five artisanal mines were sampled (Bode, Pirineu, Pinheira, Lajedo, and Marmita). Several potentially toxic metals (Be, Zn, Mn, Ba Cd, Hg, and U) were investigated in the soils and dust over the rocks and the soils. Samples from 22 individuals occupationally exposed and 17 unexposed persons, who formed the reference group, were analyzed for trace elements by an inductively coupled plasma mass spectrometer. The genotoxicity was evaluated by the micronucleus test in buccal mucosa epithelial cells, where the following changes were scored: micronuclei (MN) binucleate (BN) cells and kariolytic (KL) cells. The MN test showed significantly increased frequencies in all alterations of exposed individuals compared to the controls (p < 0.05, Student's t-test). The urine analysis showed levels of Cr, Ni Ba, Pb, and As in the blood, which were higher than the ATSDR recommended levels. The association between the MN test and the trace element concentrations found in the blood and urine was significant (p < 0.05). The higher the number of years of working, the higher the concentrations in the blood were, due to chronic exposure. The results of the present study indicate environmental contamination and a potential risk to the health of miners, suggesting an intervention.

Age features of buccal epithelium in practically healthy people

Recently, buccal epithelium has been used to study age-dependent processes. This approach is of particular relevance due to its non-invasiveness. The purpose of this study is to establish the normal values of the buccal cytogram in different age groups, including athletes. 200 practically healthy volunteers of different ages were examined, who were divided into 5 groups in accordance with the WHO age classification. In addition, 125 professional athletes took part in the study. All patients underwent a comprehensive dental examination and a standard cytological examination of buccal smears. It has been established that the cytological characteristics of buccal epitheliocytes, indirectly reflecting disorders of the nuclear apparatus of the cell, did not change significantly with age, but there was a certain upward trend in the number of cells with such anomalies (micronucleus, protrusions).The number of binuclear cells and the apoptotic index also slightly increase with age. At the same time, a high positive correlation was found between the apoptosis index and senile age. In young athletes, an increase in the number of buccal epitheliocytes with a perinuclear vacuole (an early sign of cell damage) was foundAnalysis of the cytological examination results of the buccal epithelium in people a slight increase in the level of cytological abnormalities in old age, in particular, signs of apoptosis. In addition, in healthy young athletes (18 years old - 44 years old), an increase in the number of cells with signs of nuclear degradation, which most likely reflects increased mechanical stress on the maxillofacial apparatus during sports activities.

Occupational health hazards and wide spectrum of genetic damage by the organic solvent fumes at the workplace: A critical appraisal

Long-term exposure to organic solvents is known to affect human health posing serious occupational hazards. Organic solvents are genotoxic, and they can cause genetic changes in the exposed employees' somatic or germ cells. Chemicals such as benzene, toluene, and gasoline induce an excessive amount of genotoxicity results either in genetic polymorphism or culminates in deleterious mutations when concentration crosses the threshold limits. The impact of genotoxicity is directly related to the time of exposure, types, and quantum of solvent. Genotoxicity affects almost all the physiological systems, but the most vulnerable ones are the nervous system, reproductive system, and blood circulatory system. Based on the available literature report, we propose to evaluate the outcomes of such chemicals on the exposed humans at the workplace. Attempts would be made to ascertain if the long-term exposure makes a person resistant to such chemicals. This may seem to be a far-fetched idea but has not been studied. The health prospect of this study is envisaged to complement the already existing data facilitating a deeper understanding of the genotoxicity across the population. This would also demonstrate if it correlates with the demographic profile of the population and contributes to comorbidity and epidemiology.

Micronucleus and Its Significance in Effusion Fluids

Background:

Micronucleus (MN) is an extranuclear body within the cell formed due to failure of incorporation of whole chromosomes or their fragments during cell division. MN scoring can be done to identify malignant effusions.

Aims:

This study aimed to score micronuclei to distinguish malignant effusion from benign effusions and to correlate MN score with type of malignant effusion.

Methods and Materials:

A retrospective study was conducted on 30 malignant and 30 benign effusions. The number of micronucleated cells per 1,000 cells was counted in effusion smears stained with Papanicolaou stain under oil immersion (1,000×).

Results:

The mean MN score in malignant effusions was 3.77 with standard deviation (SD) of 2.13. The mean MN score in benign effusions was 0.50 with SD of 0.57. The difference in MN score between malignant and benign effusions is statistically significant (P < 0.001). A cut-off MN score of 6.5 was seen to distinguish malignant and benign effusions with 100% specificity and 100% sensitivity in this study.

Conclusions:

MN score is higher in malignant effusions when compared with benign effusions. This can be used to differentiate malignant effusions from benign effusions in low resource setting.