Nuclear anomalies in exfoliated buccal epithelial cells of petrol station attendants in Udaipur, Rajasthan

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.

Exploratory Study on Micronuclei and Metanuclear Abnormalities in Exfoliated Buccal Cells of COVID-19 Suspected Patients

Context

SARS-CoV-2 virus causes COVID-19 by infecting nasal and oral cavities primarily by attaching its spike proteins to ACE 2 receptors expressed in epithelial cells.

Aim

This study was done to evaluate the micronucleated cell count, metanuclear abnormalities, and genotoxic factor in exfoliated buccal mucosal cell among the COVID-19 suspected patients.

Settings and Design

This cross-sectional study was conducted at AIIMS, Mangalagiri, between August and October 2022.

Methods

One hundred COVID-19 suspected patients were recruited for this study after obtaining informed and written consent; buccal smear was obtained and stained for papanicolaou test (PAP). The PAP-stained slides were analyzed for micronuclei (MN), pyknotic, karyolytic, and karyorrhexic cell count, respectively. Based on their reverse transcription-polymerase chain reaction (RT-PCR) report, the patients were grouped into COVID-19 positive and negative groups.

Statistical Analysis

The genotoxicity factor was calculated using the micronucleated cell count from both the groups using mean and standard deviation.

Results

The MN, micronucleated cell, pyknotic, karyolitic, and karyorrhexic cell count in COVID-19 positive patients were 24.12, 15.24, 3.08, 2.88 and 4.40, respectively, than COVID-19 negative patients 5.69, 8.17, 1.08, 1.00 and 2.43, respectively. The genotoxicity factor for SARS-CoV-2 was 2.68 which is a positive genotoxic effect on buccal mucosal cells.

Conclusion

SARS-CoV-2 increases the expression of micronucleated cells, pyknotic cells, karyolytic cells, and karyorhexic cells and concludes SARS-CoV-2 is having cytogenotoxic effect on the buccal mucosal cells. This can be used as a reliable marker in identifying the early carcinogenic effects of virus causing COVID-19.

Genotoxicity in Oral Mucosal Epithelial Cells of Petrol Station Attendants: A Micronucleus Study

Introduction:

Occupational exposure to petrol derivatives possesses an increased risk of various cancers including that of the oral mucosa. Scientific studies have shown the correlation of micronuclei assay (MN) with the cytogenotoxic changes in petrol station attendants. However, very few have reported the use of MN assay as a promising tool for assessing the impact of smoking in these workers.

Aim:

To explore the cytogenotoxic damage in exfoliated buccal cells obtained from petrol station attendants and control subjects using the MN assay along with additional effects due to smoking.

Materials and Methods:

The study comprised 60 males who were divided into Group I–IV with each having 15 subjects. These subjects were categorized as exposed smokers, exposed nonsmokers, unexposed smoker group, and unexposed nonsmokers. The MN and additional nuclear abnormalities (karyorrhexis [KH], binucleation [BN], pyknosis [P], and karyolysis [KL]) were calculated in PAP-stained slides.

Results:

Statistically higher mean frequencies of overall nuclear anomalies were observed in petrol pump workers in comparison with the control group. Petrol pump smokers carry the highest nuclear anomalies followed by non-exposed smokers than exposed non-smokers and the count was the least among unexposed non-smoker workers.

Discussion and Conclusion:

The present study indicated that the petrol pump workers are under higher cytogenotoxic damage. Also, smoking added to the frequency of damage. Thus, MN and other nuclear anomalies are in-vitro reliable biomarker assays available and should be routinely employed as a screening tool in their periodic medical evaluation.

Mitochondrial DNA copy number and cytogenetic damage among fuel filling station attendants

Fuel filling attendants are constantly exposed to the complex mixture of gasoline and all refinery environments are probably carcinogenic for humans. These workers are considered as an unorganized group in India and unaware of the risk. The present study was focused to monitor workplace pollutants (particulate matter size 10 [PM10 μm], total volatile organic compound [VOC], and carbon monoxide [CO]), benzene exposure (phenol), and to evaluate their genotoxicity effect with reference to relative mitochondrial DNA copy number (MtDNAcn), 8-OHdG (8-hydroxy-2'-deoxyguanosine), and micronuclei (MN) frequency (%) among fuel filling attendants. This study recorded 318 ± 134 and 1,050 ± 260 μg/m³ time-weighted average concentration of PM10 and CO, respectively. However, total VOC levels recorded were below the detectable level (BDL) to 290 ± 50 μg/m³ . A total of 53 subjects (26 exposed and 27 control) participated in this study with similar sociodemographic information. It was noticed that fuel filling attendants were not using proper personal protective equipment (PPE) and are younger generation. The significantly (p = <.001) higher level of phenol, a metabolite of benzene, was detected in the exposed group. The significantly elevated level of urinary 8-OHdG (p = .01), MN frequency (p = .001), and relative MtDNAcn (p = .001) was observed in exposed group as compared to the control group. The study exemplify that workers were exposed to the benzene, workplace pollutant, and observed genotoxicity suggest malignancy risk. This study highlights the importance of biomonitoring in occupational settings to avoid malignancies. The possible engineering controls, frequent health check-ups, awareness about the risks, and PPE use can reduce health hazards.