title: The micronucleus assay as a biological dosimeter in hospital workers exposed to low doses of ionizing radiation.
abstract: The health risk associated with low levels of ionizing radiation is still a matter of debate. A number of factors, such as non-target effects, adaptive responses and low-dose hypersensitivity, affect the long-term outcome of low-dose exposures. Cytogenetic bio-dosimetry provides a measure of the absorbed dose, taking into account the individual radiation sensitivity. The aim of the present study is to evaluate the value of the micronucleus (MN) test as a bio-dosimeter in hospital workers exposed to low doses of ionizing radiation. Blood samples were obtained from 30 subjects selected among workers exposed to X- and gamma-radiation, and 30 controls matched for sex, age and smoking from the same hospital. Micronucleus frequencies were analyzed by use of the cytokinesis-block method. The MN frequency was compared among the groups considering the confounding factors and the length of employment. No increase in the number of bi-nucleated cells with MN (BNMN), but a significant increase in the number of mono-nucleated cells with micronuclei (MOMN) was observed in exposed subjects compared with the controls. The relationship between MN frequency and accumulated dose (mSv) was evaluated. The length of employment did not affect the extent of MN frequency, but an increase of BNMN and MOMN cells was observed based on the accumulated radiation dose. Our study shows the sensitivity of the MN test in the detection of cytogenetic effects of cumulative exposure levels, suggesting the potential usefulness of this assay in providing a biological index in medical surveillance programs.
authors.affiliation: Environmental Carcinogenesis Unit, IRCCS Azienda Ospedaliera Universitaria San Martino -IST, Istituto Nazionale Ricerca sul Cancro, Largo R. Benzi 10, 16132, Genova, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Ropolo
authors.affiliation: Environmental Carcinogenesis Unit, IRCCS Azienda Ospedaliera Universitaria San Martino -IST, Istituto Nazionale Ricerca sul Cancro, Largo R. Benzi 10, 16132, Genova, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Balia
authors.affiliation: Environmental Carcinogenesis Unit, IRCCS Azienda Ospedaliera Universitaria San Martino -IST, Istituto Nazionale Ricerca sul Cancro, Largo R. Benzi 10, 16132, Genova, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Roggieri
authors.affiliation: Occupational Health Unit S.Orsola-Malpighi Hospital, 40138 Bologna, Italy.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Lodi
authors.affiliation: Occupational Health Unit S.Orsola-Malpighi Hospital, 40138 Bologna, Italy.
authors.forename: Maria Concetta
authors.initials: MC
authors.lastname: Nucci
authors.affiliation: Occupational Health Unit S.Orsola-Malpighi Hospital, 40138 Bologna, Italy.
authors.forename: Francesco Saverio
authors.initials: FS
authors.lastname: Violante
authors.affiliation: Environmental Carcinogenesis and Risk Assessment, Environmental Protection and Health Prevention Agency-Emilia Romagna Region (ER-EPA), 40126 Bologna, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Silingardi
authors.affiliation: Occupational Health Unit S.Orsola-Malpighi Hospital, 40138 Bologna, Italy.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Colacci
authors.affiliation: Environmental Carcinogenesis Unit, IRCCS Azienda Ospedaliera Universitaria San Martino -IST, Istituto Nazionale Ricerca sul Cancro, Largo R. Benzi 10, 16132, Genova, Italy. Electronic address: claudia.bolognesi@istge.it.
authors.forename: Claudia
authors.initials: C
authors.lastname: Bolognesi
mesh_terms: D000328:Adult; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects; D006801:Humans; D008297:Male; D015162:Micronucleus Tests / Q000379:methods; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D010564:Personnel, Hospital; D011829:Radiation Dosage; D011839:Radiation, Ionizing; D014965:X-Rays / Q000009:adverse effects