Suitability of Conjunctival Mucosa Cytological Samples for Genotoxic Assessment: Micronucleus Assay Applied to Workers Exposed to Ionizing Radiation
Main Article Content
Abstract
This study investigated an alternative, less invasive approach for implementing genetic biomonitoring in healthcare professionals occupationally exposed to ionizing radiation. The main objectives were to evaluate the suitability of conjunctival mucosa as a cellular sample for the micronucleus assay in occupationally exposed individuals and to contribute to the development of less invasive strategies for occupational genetic monitoring. Using sterile brushes for ocular mucosa sampling, 20 volunteers were recruited from hospital and academic institutions, following strict ethical and clinical criteria. Samples were processed using a cytocentrifuge and stained with Giemsa, allowing morphological analysis under light microscopy. Despite challenges related to low cellularity, structural preservation was sufficient for the identification of micronuclei and other relevant nuclear abnormalities. The results indicate that the methodology is well tolerated, low-cost, technically simple, and feasible for large-scale application, particularly in clinical settings with limited infrastructure. Therefore, conjunctival mucosa may represent a promising matrix for occupational genotoxic screening, offering significant contributions to public health surveillance strategies and the prevention of cumulative genetic effects in exposed professionals.
Keywords:
Occupational Genotoxicity, Micronucleus Assay, Conjunctival Mucosa, Ionizing Radiation
Article Details
How to Cite
PADILHA, Catia Martins leite et al.
Suitability of Conjunctival Mucosa Cytological Samples for Genotoxic Assessment: Micronucleus Assay Applied to Workers Exposed to Ionizing Radiation.
Medical Research Archives, [S.l.], v. 13, n. 8, aug. 2025.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/6819>. Date accessed: 05 dec. 2025.
doi: https://doi.org/10.18103/mra.v13i8.6819.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
References
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19. Drummond RL, Rhoden CR, Lubianca Neto JF, Fleck A da S, Padoin RCPK, Amantéa SL. Micronucleus count in nasal epithelial cells from patients with chronic rhinosinusitis and polyps. Braz J Otorhinolaryngol. Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial.; 2020 Dec 11;86:743–747.
20. Bannier-Hélaouët M, Korving J, Ma Z, Begthel H, Giladi A, Lamers MM, Van De Wetering WJ, Yawata N, Yawata M, LaPointe VLS, Dickman MM, Kalmann R, Imhoff SM, Van Es JH, López-Iglesias C, Peters PJ, Haagmans BL, Wu W, Clevers H. Human conjunctiva organoids to study ocular surface homeostasis and disease. Cell Stem Cell. Elsevier BV; 2024 Feb;31(2):227-243.e12.
21. Branisteanu D, Stoleriu G, Branisteanu D, Boda D, Branisteanu C, Maranduca M, Moraru A, Stanca H, Zemba M, Balta F. Ocular cicatricial pemphigoid (Review). Exp Ther Med [Internet]. Spandidos Publications; 2020 Jul 7 [cited 2025 Jul 9]; Available from: http://www.spandidos-publications.com/10.3892/etm.2020.8972
22. Blakely EA, Kleiman NJ, Neriishi K, Chodick G, Chylack LT, Cucinotta FA, Minamoto A, Nakashima E, Kumagami T, Kitaoka T, Kanamoto T, Kiuchi Y, Chang P, Fujii N, Shore RE. Radiation Cataractogenesis: Epidemiology and Biology. Radiat Res. 2010 May;173(5):709–717.
23. Silva RR, De Carli JP, Collares K, Vanini J, Presotto JS, Vargas JE, Loguercio AD, Benetti P. Reply to the opinion paper: is micronucleus test a suitable method for monitoring oral mucosa exposed to dental bleachings in smokers? Arch Toxicol. 2023 Jul;97(7):2031–2033.
24. Wojcik A, Kowalska M, Bouzyk E, Buraczewska I, Kobialko G, Jarocewicz N, Szumiel I. Validation of the micronucleus-centromere assay for biological dosimetry. Genet Mol Biol. 2000 Dec;23(4):1083–1085.
25. Valente D, Costa-Amaral IC, Carvalho LVBD, Santos MVCD, Castro VSD, Rodrigues DDRF, Falco AD, Silva CB, Nogueira SM, Gonçalves ES, Moreira JC, André LC, Teixeira LR, Sarcinelli PDN, Sisenando HA, Oliveira MSD, Perini JA, Mattos RDCODC, Larentis AL. Utilização de biomarcadores de genotoxicidade e expressão gênica na avaliação de trabalhadores de postos de combustíveis expostos a vapores de gasolina. Rev Bras Saúde Ocupacional [Internet]. 2017 [cited 2024 May 5];42(suppl 1). Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0303-76572017001000402&lng=pt&tlng=pt
26. Brand CI, Fontana RT, Santos AV dos. A saúde do trabalhador em radiologia: algumas considerações. Texto Contexto - Enferm. 2011 Mar;20(1):68–75.
27. Tolbert PE, Shy CM, Allen JW. Micronuclei and other nuclear anomalies in buccal smears: methods development. Mutat Res Mutagen Relat Subj. 1992 Feb;271(1):69–77.
28. Méndez NP, Azevedo MG, Cargnin LS, Seibel MP, Silva AFD, Franceschini MEM, Rocha RS, Pigatto JAT. Morfologia das células endoteliais corneanas bovinas obtidas com alizarina vermelha e microscopia óptica. Ciênc Anim Bras [Internet]. FapUNIFESP (SciELO); 2024 [cited 2025 Jul 9];25. Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1809-68912024000100214&tlng=pt
29. Willegaignon J, Fernandes SCP, Pelissoni RA, Coura-Filho GB, Sapienza MT, Buchpiguel CA. Radiation safety measures in diagnostic nuclear medicine, based on the potential radiation dose emitted by radioactive patients. Radiol Bras. Publicação do Colégio Brasileiro de Radiologia e Diagnóstico por Imagem; 2023 Mar 13;56:13–20.
30. Ganesan N, Phansalkar M, Ambroise M, Varghese R. Validating micronucleus score in effusion fluids. J Cytol. 2017;34(4):193.
31. Bhattathiri VN, Bindu L, Remani P, Chandralekha B, Davis CA, Nair MK. Serial cytological assay of micronucleus induction: a new tool to predict human cancer radiosensitivity. Radiother Oncol. 1996 Nov 1;41(2):139–142.
32. Ferreira MDCM, Nogueira MC, Ferreira LDCM, Bustamante-Teixeira MT. Early detection and prevention of cervical cancer: knowledge, attitudes and practices of FHS professionals. Ciênc Saúde Coletiva. 2022 Jun;27(6):2291–2302.
33. Tariq F. Allergic Conjunctivitis: Review of Current Types, Treatments, and Trends. Life. MDPI AG; 2024 May 21;14(6):650.
2. Kuchi Bhotla H, Balasubramanian B, Rengasamy KRR, Arumugam VA, Alagamuthu KK, Chithravel V, Chaudhary A, Alanazi AM, Pappuswamy M, Meyyazhagan A. Genotoxic repercussion of high-intensity radiation (x-rays) on hospital radiographers. Environ Mol Mutagen. 2023 Feb;64(2):123–131. PMID: 36541415
3. Okuno E. Efeitos biológicos das radiações ionizantes: acidente radiológico de Goiânia. Estud Av. Instituto de Estudos Avançados da Universidade de São Paulo; 2013;27:185–200.
4. Okuno E. Radiação: Efeitos, Riscos e Benefícios. 2018; Available from: https://s3-sa-east-1.amazonaws.com/ofitexto.arquivos/Radiacao-Efeitos-Riscos-e-Benef%C3%ADcios-DEG.pdf
5. Çobanoğlu H, Çayır A. Occupational exposure to radiation among health workers: Genome integrity and predictors of exposure. Mutat Res Toxicol Environ Mutagen. 2024 Jan;893:503726.
6. Antonio EL, Nascimento AJ do, Lima AAS de, Leonart MSS, Fernandes Â. GENOTOXICIDADE E CITOTOXICIDADE DOS RAIOS X EM CRIANÇAS SUBMETIDAS À RADIOGRAFIA PANORÂMICA. Rev Paul Pediatr. Sociedade de Pediatria de São Paulo; 2017 Jul 20;35:296–301.
7. Gallo AM, Lima FAC de, Reis LM dos, Cremer E. EXPOSIÇÃO OCUPACIONAL À RADIAÇÕES IONIZANTES SOB A ÓTICA DE PROFISSIONAIS DE ENFERMAGEM EM HEMODINÂMICA. Rev Rene. 2013;14(1):109–119.
8. Navarro MVT, Leite HJD, Alexandrino J da C, Costa EA. Controle de riscos à saúde em radiodiagnóstico: uma perspectiva histórica. História Ciênc Saúde-Manguinhos. 2008 Dec;15(4):1039–1047.
9. Higgins A. Measurement of occupational doses of ionising radiation to the lens of the eyes of interventional radiologists. J Radiol Prot. 2016 Mar;36(1):74–92.
10. Leyton F, Canevaro L, Dourado A, Castello H, Bacelar A, Navarro MT, Vañó E, Nogueira M do S, Batista WO, Furquim TAC, Lykawka R, Melo CS, Borges F, Rodrigues B. Riscos da Radiação X e a Importância da Proteção Radiológica na Cardiologia Intervencionista: Uma Revisão Sistemática. Rev Bras Cardiol Invasiva. Sociedade Brasileira de Hemodinâmica e Cardiologia Intervencionista - SBHCI; 2014 Mar;22:87–98.
11. Vaiserman A, Koliada A, Zabuga O, Socol Y. Health Impacts of Low-Dose Ionizing Radiation: Current Scientific Debates and Regulatory Issues. Dose-Response. 2018 Jul 1;16(3):155932581 8796331.
12. Padilha CML, Filho LGP, Ferreira R da P, Souza SAL de. Cytopathology and the Micronucleus Test in Monitoring Post-Radiotherapy Patients for Cervical Cancer. Med Res Arch [Internet]. 2023 Oct 25 [cited 2024 Aug 8];11(10). Available from: https://esmed.org/MRA/mra/article/view/4555
13. Leonardi S, Poma AM, Colafarina S, D’Aloisio F, Scatigna M, Zarivi O, Mastrantonio R, Tobia L, Fabiani L. Early genotoxic damage through micronucleus test in exfoliated buccal cells and occupational dust exposure in construction workers: a cross-sectional study in L’Aquila, Italy. Ecotoxicol Environ Saf. 2020 Oct 15;203:110989. PMID: 32888600
14. Thomas P, Holland N, Bolognesi C, Kirsch-Volders M, Bonassi S, Zeiger E, Knasmueller S, Fenech M. Buccal micronucleus cytome assay. Nat Protoc. 2009 Jun;4(6):825–837.
15. Padilha C. Avaliação Cito-Oncótica de Pacientes com Câncer de Colo Uterino Submetidas a Radioterapia. [Departamento de Radiologia]: UFRJ. Faculdade de Medicina; 2021.
16. Jirsova K, Juklova K, Alfakih A, Filipec M. Presence of snake-like chromatin in epithelial cells of keratoconjunctivitis sicca followed by a large number of micronuclei. Acta Cytol. 2007;541–6.
17. Silva RCG, Figueirêdo RDPV, Silva ACO, Lima CEQ, Oliveira SR, Peres AL. Cytopathologic follow-up of women with cervical cancer post-radiotherapy: case series. J Bras Patol E Med Lab [Internet]. 2018 [cited 2023 Aug 11];54(2). Available from: http://www.gnresearch.org/doi/10.5935/1676-2444.20180018
18. Barros JDN, Almeida SRAD, Lowen MS, Cunha MCD, Gomes JÁP. Impression cytology in the evaluation of ocular surface tumors: review article. Arq Bras Oftalmol. 2015;78(2):126–132.
19. Drummond RL, Rhoden CR, Lubianca Neto JF, Fleck A da S, Padoin RCPK, Amantéa SL. Micronucleus count in nasal epithelial cells from patients with chronic rhinosinusitis and polyps. Braz J Otorhinolaryngol. Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial.; 2020 Dec 11;86:743–747.
20. Bannier-Hélaouët M, Korving J, Ma Z, Begthel H, Giladi A, Lamers MM, Van De Wetering WJ, Yawata N, Yawata M, LaPointe VLS, Dickman MM, Kalmann R, Imhoff SM, Van Es JH, López-Iglesias C, Peters PJ, Haagmans BL, Wu W, Clevers H. Human conjunctiva organoids to study ocular surface homeostasis and disease. Cell Stem Cell. Elsevier BV; 2024 Feb;31(2):227-243.e12.
21. Branisteanu D, Stoleriu G, Branisteanu D, Boda D, Branisteanu C, Maranduca M, Moraru A, Stanca H, Zemba M, Balta F. Ocular cicatricial pemphigoid (Review). Exp Ther Med [Internet]. Spandidos Publications; 2020 Jul 7 [cited 2025 Jul 9]; Available from: http://www.spandidos-publications.com/10.3892/etm.2020.8972
22. Blakely EA, Kleiman NJ, Neriishi K, Chodick G, Chylack LT, Cucinotta FA, Minamoto A, Nakashima E, Kumagami T, Kitaoka T, Kanamoto T, Kiuchi Y, Chang P, Fujii N, Shore RE. Radiation Cataractogenesis: Epidemiology and Biology. Radiat Res. 2010 May;173(5):709–717.
23. Silva RR, De Carli JP, Collares K, Vanini J, Presotto JS, Vargas JE, Loguercio AD, Benetti P. Reply to the opinion paper: is micronucleus test a suitable method for monitoring oral mucosa exposed to dental bleachings in smokers? Arch Toxicol. 2023 Jul;97(7):2031–2033.
24. Wojcik A, Kowalska M, Bouzyk E, Buraczewska I, Kobialko G, Jarocewicz N, Szumiel I. Validation of the micronucleus-centromere assay for biological dosimetry. Genet Mol Biol. 2000 Dec;23(4):1083–1085.
25. Valente D, Costa-Amaral IC, Carvalho LVBD, Santos MVCD, Castro VSD, Rodrigues DDRF, Falco AD, Silva CB, Nogueira SM, Gonçalves ES, Moreira JC, André LC, Teixeira LR, Sarcinelli PDN, Sisenando HA, Oliveira MSD, Perini JA, Mattos RDCODC, Larentis AL. Utilização de biomarcadores de genotoxicidade e expressão gênica na avaliação de trabalhadores de postos de combustíveis expostos a vapores de gasolina. Rev Bras Saúde Ocupacional [Internet]. 2017 [cited 2024 May 5];42(suppl 1). Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0303-76572017001000402&lng=pt&tlng=pt
26. Brand CI, Fontana RT, Santos AV dos. A saúde do trabalhador em radiologia: algumas considerações. Texto Contexto - Enferm. 2011 Mar;20(1):68–75.
27. Tolbert PE, Shy CM, Allen JW. Micronuclei and other nuclear anomalies in buccal smears: methods development. Mutat Res Mutagen Relat Subj. 1992 Feb;271(1):69–77.
28. Méndez NP, Azevedo MG, Cargnin LS, Seibel MP, Silva AFD, Franceschini MEM, Rocha RS, Pigatto JAT. Morfologia das células endoteliais corneanas bovinas obtidas com alizarina vermelha e microscopia óptica. Ciênc Anim Bras [Internet]. FapUNIFESP (SciELO); 2024 [cited 2025 Jul 9];25. Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1809-68912024000100214&tlng=pt
29. Willegaignon J, Fernandes SCP, Pelissoni RA, Coura-Filho GB, Sapienza MT, Buchpiguel CA. Radiation safety measures in diagnostic nuclear medicine, based on the potential radiation dose emitted by radioactive patients. Radiol Bras. Publicação do Colégio Brasileiro de Radiologia e Diagnóstico por Imagem; 2023 Mar 13;56:13–20.
30. Ganesan N, Phansalkar M, Ambroise M, Varghese R. Validating micronucleus score in effusion fluids. J Cytol. 2017;34(4):193.
31. Bhattathiri VN, Bindu L, Remani P, Chandralekha B, Davis CA, Nair MK. Serial cytological assay of micronucleus induction: a new tool to predict human cancer radiosensitivity. Radiother Oncol. 1996 Nov 1;41(2):139–142.
32. Ferreira MDCM, Nogueira MC, Ferreira LDCM, Bustamante-Teixeira MT. Early detection and prevention of cervical cancer: knowledge, attitudes and practices of FHS professionals. Ciênc Saúde Coletiva. 2022 Jun;27(6):2291–2302.
33. Tariq F. Allergic Conjunctivitis: Review of Current Types, Treatments, and Trends. Life. MDPI AG; 2024 May 21;14(6):650.