Cytogenetic biomonitoring carried out in a village (Dolon) adjacent to the Semipalatinsk nuclear weapon test site

Abstract

The Semipalatinsk region (Kazakhstan Republic) has been affected by extensive radioactive contamination due to more than 450 nuclear tests of which almost 100 were exploded in the atmosphere. The present results refer to cytogenetic assessments in a study cohort of the population of Dolon, a settlement located on the NE boundary of the nuclear weapon test site, which was exposed to elevated doses of ionising radiation primarily due to the first Soviet nuclear test in 1949. Conventional cytogenetic analyses were carried out on 21 blood samples from individuals (more than 50 years old) living in Dolon since the very beginning of nuclear testing. A matched control group included 20 individuals living in non-contaminated areas. Higher frequencies of chromosome aberrations were found in the Dolon cohort compared to the control group, even though they remain within the range of the background levels reported for large normal human population studies on elderly individuals.

Background Level of Unstable Chromosome Aberrations in the Kazakhstan Population: A Human Biomonitoring Study

“…In the present study, considering entirely the studied cohort, a mean frequency of Dic + CR of 0.84 (±0.83) per 1000 cells was found. This value is very similar to other published data on Kazakhstan control subjects reported in previous studies ( Table 3 ) [ 19 , 22 , 23 , 26 , 27 , 33 ]. In particular, a mean dicentric frequency of 0.71‰ was found in a group of control subjects from Kurchatov in northeast Kazakhstan [ 19 ], while a dicentric frequency of 0.78‰ was found in a group of controls from Kokpekty in East Kazakhstan [ 27 ].…”

“…Since 2018, Kazakhstan has been a member of the ARADOS (Asian Network of Biological Dosimetry) network [ 18 ], which is a platform for radiation dosimetry research among Asian countries. In addition, Kazakhstan has participated in many epidemiological studies using biological dosimetry techniques such as dicentrics, FISH translocations and physical dosimetry methods [ 19 , 20 , 21 , 22 , 23 ] as well as research on the biological effects of radiation on the human body, which further confirms the importance of research in this direction [ 24 ].…”

Eurados review of retrospective dosimetry techniques for internal exposures to ionising radiation and their applications

“…In the first four decades of nuclear testing direct individual measurements of the radiation burden to the members of the overexposed population were not carried out either by bioassay or external retrospective dosimetry assays. The studies by biological methods (Ilyinskikh et al 1997 , 1998 ; Tanaka et al 2000 , 2006 ; Testa et al 2001 ; Stephan et al 2001 ; Salomaa et al 2002 ; Chaizhunusova et al 2006 ; Takeichi et al 2006 ) or EPR or TL retrospective dosimetry (Ivannikov et al 2006 ; Stepanenko et al 2006 , 2007 ; Zhumadilov et al 2006 , 2013 ; Sholom et al 2007 ) were not made until the 1990s. Published reports in English language literature are available only after 1995.…”

“…Several biological dosimetry studies with the conventional cytogenetic techniques (by unstable chromosome aberrations: DC and MN assays) were performed about five decades after the beginning of the nuclear tests in 1949. These studies suggested that the current increased levels of unstable-type chromosome aberrations in the inhabitants of the most contaminated areas were mainly due to internal exposure (Tanaka et al 2000 , 2006 ; Testa et al 2001 ; Takeichi et al 2006 ) but these methods were not appropriate for long-term individual retrospective dose assessment.…”

Radiation Science After the Cold War. The Politics of Measurement, Risk, and Compensation in Kazakhstan

“…While acknowledging the uncertainties in the method for determining radiation doses obtained decades ago, Western researchers considered a classic marker, dicentrics (one type of chromosome aberrations), suitable for detecting 'hallmarks of exposure to ionizing radiation' (Testa et al, 2001) and thus used it in the validation studies. The EU-funded project stated its objective in terms of 'verify(ing) the hypothesis of existing contamination' (Testa et al, 2001). In some of these documents, it becomes clear that at the core of the concern was the credibility of the Western scientists to their own research communities.…”