The Results of Selective Cytogenetic Monitoring of Chernobyl Accident Victims in the Ukraine

Abstract

Selective cytogenetic monitoring of the highest priority groups of Chernobyl disaster victims has been carried out since 1987. In 1992-1993, 125 liquidators (irradiated mainly in 1986) and 42 persons recovering from acute radiation sickness of the second and third degrees of severity were examined. Cytogenetic effects (an elevated level of unstable as well as stable markers of radiation exposure) were found in all groups, which showed a positive correlation with the initial degree of irradiation severity even 6-7 y after the accident. Comparative scoring of conventional staining vs. G-banding in 10 liquidators showed the identical rate of unstable aberrations. At the same time, the yield of stable aberrations for G-banded slides exceeded the frequency for conventional staining. In order to study possible mutagenic activity of chronic low levels of irradiation, the cytogenetic monitoring of some critical groups of the population (especially children and occupational groups--tractor drivers and foresters) living in areas of the Ukraine contaminated by radionuclides was carried out. In all the examined groups, a significant increase in the frequency of aberrant metaphases, chromosome aberrations (both unstable and stable), and chromatid aberrations was observed. Data gathered from groups of children reflect the intensity of mutagenic impact on the studied populations and demonstrate a positive correlation with the duration of exposure. Results of cytogenetic examination of adults confirmed the importance of considering the contribution of occupational radiation exposure to genetic effects of Chernobyl accident factors on the population of contaminated areas. Results of our investigations demonstrated the possibility of evaluating the mutagenic impact of acute and long-term irradiation of different intensities on somatic cells of persons undergoing radiation exposure due to the Chernobyl accident and confirmed the need to introduce new informative genetic methods [especially fluorescence in situ hybridization (FISH)] for reliable retrospective cytogenetic dosimetry of radiation exposure in Chernobyl accident victims.

Eight-year follow-up study of three individuals accidentally exposed to 60Co radiation: Chromosome aberration and micronucleus analysis

“…However, a history of smoking was observed to have some effects on the chromosome translocation frequency [24]; follow-up studies of exposed subjects are needed to characterize the risk analyses further. GBanding karyotyping has been applied to the follow-up of radiation accident victims from the 1970s/80s, and many laboratories use the FISH technique to score translocations [25,26]. However, FISH has some uncertainties, such as adjustment for genome equivalence.…”

Radioisotopes of cesium and experience of cytogenetic dosimetry in emergency situations

“…Радіоцезій є одним з небагатьох радіоізотопів (крім тритію та радіойоду у пацієнтів без щитоподібної залози), який у разі інкорпорації майже рівномірно розподіляється по тканинах організму [24, 103 -106]. Це надає можливість розробки цитогенетичних методів оцінки дози, обумовленого ним внутрішнього опромінення (на відміну від альфа-випромінюючих ізотопів та радіоізотопу 90 Sr).…”

“…Ефективність бета-частинок досліджена дуже мало і стосується в основному 3 H та 90 Sr [115 -123]. Так дослідження з використанням 90 Sr (за безпосереднього контакту клітин з радіоізотопом) показали, що можуть бути відмінності між бета-частинками та гамма-квантами в ефективності індукції пошкоджень ДНК [124] або хромосомних аберацій [118].…”

Design and analysis of epidemiological studies of excess cancer among children exposed to chernobyl radionuclides

“…An ongoing task has been the search for a test that will estimate doses below 50 cGy accurately and reliably. Pilinskaya has shown that, among Ukrainian liquidators and children exposed environmentally to Chernobyl radionuclides, while there was not always a strong correlation between individual unstable chromosome aberration and individual physical dose estimates, there was a rather good correlation between average regional dose and average chromosome aberration [69]. FISH is a technique which is an extension of cytogenetic analysis [67,.…”