Tritium Effect on Human Body
Health-Biological Study of Tritium and Tritium Oxide Effect on Human Organism.
Tech Area / Field
3 Approved without Funding
VNIIEF, Russia, N. Novgorod reg., Sarov
Краткое описание проектаThe objective of the project is to study the biological effect of tritium and tritium compounds on the human organism.
The urgency of this study is due to the fact that, first, tritium is one of radiobiologically significant radionuclides entering the environment from natural and technogeneous sources. The latter include NPP and other nuclear fuel cycle institutions and nuclear testing (in the past). Second, the radiobiological effects of tritium on the human body within a low dose range have not been adequately studied.
Tritium is characterized with essentially uniform distribution in the water pool of the organism irrespective of the intake path. Tritium easily incorporates into biologically active molecules, is able to exchange with hydrogen of chromosome DNA which can lead to prolongation of its biological half-life and higher risk of delayed effects, including carcinogenic risk. Therefore, assessment of the carcinogenic radiation risk of tritium effect is surely extremely urgent.
Owing to the need to study the mechanisms of tritium compound behavior at various intake pathways, as well as biological dosimetry issues, the project includes a section devoted to research into tritium and tritium oxide assimilation by the human organism at various intake paths (inhalation, peroral and percutaneous).
The project provides for retrospective analysis of results for studying tritium assimilation in professionals conducted in the 1960s. The data of tritium distribution in the human organism at various intake paths is needed to interpret the environment monitoring results when estimating the inpidual absorbed doses and studying the tritium biological effect on the human organism, as well as to secure personnel and population radiation protection.
A cohort of nuclear professionals who have handled tritium or tritium oxide (400 persons), as well as a control cohort of inpiduals not exposed to radiations (1000 persons) will be formed.
One of important work stages is devoted to reconstruction of inpidual absorbed doses of professionals who have handled tritium. This task will be accomplished both using models of tritium assimilation by human body basing on the dosimetry information available at VNIIEF and using cytogenic methods: analysis of the rate of stable and unstable chromosomal aberrations in peripheral blood lymphocytes. It is planned to analyze the induction rate of translocations and other chromosome rearrangements using the FISH method (fluorescence in situ hybridization painting of metaphase slides with specific DNA probes).
The Project will result in studied level of stable and unstable chromosomal aberrations in professionals' lymphocytes and dose reconstruction using the dose-effect response curve for stable chromosomal aberration yield under action of tritium beta radiation on blood lymphocytes in vitro developed at US LLNL.
The results of the conducted retrospective analysis of absorbed doses in professionals will be used for prediction carcinogenic risk assessment in the cohort understudy.
The prediction carcinogenic risk assessment for the professionals cohort under study will be made basing on the baseline mortality using the improved risk assessment model for chronical exposure to tritium or tritium oxide. The Project provides for epidemiological studies of malignant neoplasms and general somatic morbidity depending on the absorbed dose accumulated in the group of professionals who have handled tritium or tritium oxide and in the control group of persons who have not worked under hazardous conditions.
To find the relationship between oncological diseases and environmental carcinogenic effects, the prospective method with a retrospectively selected cohort known in the epidemiology will be used.
This will result in carcinogenic risk factors in the group of professionals under study. This will allow to compare the predicted and actual factors of radiation carcinogenic risk for professionals.
The novelty of the studies conducted will consist in:
- information for tritium and tritium compound assimilation at various intake paths in the human organism;
- assessment of delayed tritium and tritium compound effects on health of professional workers.
The studies conducted within the Project will be of doubtless scientific and scientific-practical value owing to urgency of the problem of tritium and tritium oxide biological effect assessment, as well as the problem of safety for personnel handling tritium and prediction of delayed tritium effects on the human organism.
The Project will involve the following leading experts from various organizations: L.F. Byelovodsky, Sc.D. in technical sciences (Sarov), Prof.M.I. Balonov (St.Petersburg), Prof.V.A. Shevchenko (Moscow), G.P. Snigireva, Ph.D.in biology (Moscow), V.F. Demin, Ph.D.in physics and mathematics (Moscow), Prof.I.V. Osechinsky (Moscow).
Project participants are open for collaboration with scientific and development organizations, industrial and commercial companies as well as private experts from USA, EU countries, Japan and Norway.
At present, confirmation of interest to collaborate on the project is received from leading specialists of Lawrence Livermore National Laboratory (USA), Radiobiology and Radiochemistry Institutions of Munich University (Germany).
The following types of collaboration are planned:
- exchange of information during project implementation;
- joint seminars, workshops, meetings, consultations;
- participation in joint investigations;
- other types of collaboration.