Article

Complex experimental research on internal tooth dosimetry for the Techa River region: A model for 90Sr accumulation in human teeth formed by time of intakes

Urals Research Center for Radiation Medicine, Tscheljabinsk, Chelyabinsk, Russia
Radiation Measurements (Impact Factor: 1.14). 05/2006; http://dx.doi.org/10.1016/j.radmeas.2005.12.003,. DOI: 10.1016/j.radmeas.2005.12.003

ABSTRACT Samples of calcified tooth tissues (enamel, root and crown dentine) collected from the Techa riverside population exposed to radiation caused by radioactive releases from the nuclear weapon plant in South Ural were investigated. Accumulated absorbed dose in the samples was measured using the EPR-spectroscopy method. Beta activity of the samples containing radioactive 90Sr was measured by the method of low background anti-coincidence thin scintillating detection. High correlation between absorbed dose and beta activity was observed for enamel and root dentin but not for crown dentin. Otherwise, poor correlation was observed between absorbed doses as well as between beta activities for different tooth tissues of the same tooth. The results of dose measurement by EPR spectroscopy are analysed with the use of Monte Carlo simulation of dose formation due to 90Sr incorporated in tooth tissues taking into account biological elimination of 90Sr. Influence of 90Sr distribution in the tooth body on absorbed dose is discussed.

Download full-text

Full-text

Available from: Alexander Ivannikov, Jun 30, 2015
0 Followers
 · 
107 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mounting a successful online training course takes a concerted effort by a team of experts in diverse fields. This paper describes the development of a program designed to teach business English and the concepts of business communication to an international audience via the Internet. This online business English course is being developed by a private corporation (Virtual Languages Inc.), with the cooperative efforts of a university (the Florida Institute of Technology). Content experts, ESL (English as a second language) professionals, Web page designers, graphic artists and sound technicians, plus corporate officers, bring together the expertise needed to mount this innovative online course
    Professional Communication Conference, 1999. IPCC 99. Communication Jazz: Improvising the New International Communication Culture. Proceedings. 1999 IEEE International; 02/1999
  • [Show abstract] [Hide abstract]
    ABSTRACT: The approach of the Year 2000 (Y2K) has called into question the condition of readiness of computer systems upon which organizations depend. Will these systems operate reliably after midnight, January 1, 2000, or will problems associated with date calculations cause failures that adversely affect users? This question has caused organizations to identify their critical systems, test these systems for Y2K problems, and take corrective action where necessary to ensure Y2K readiness. This paper examines various technical and management issues that Southwest Research Institute has dealt with in solving these problems
    IEEE Aerospace and Electronic Systems Magazine 12/1999; 14(11):3-9. DOI:10.1109/62.809194 · 0.44 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The requirements for biodosimetric techniques used at long times after exposure, i.e., 6 months to more than 50 years, are unique compared to the requirements for methods used for immediate dose estimation. In addition to the fundamental requirement that the assay measures a physical or biologic change that is proportional to the energy absorbed, the signal must be highly stable over time to enable reasonably precise determinations of the absorbed dose decades later. The primary uses of these biodosimetric methods have been to support long-term health risk (epidemiologic) studies or to support compensation (damage) claims. For these reasons, the methods must be capable of estimating individual doses, rather than group mean doses. Even when individual dose estimates can be obtained, inter-individual variability remains as one of the most difficult problems in using biodosimetry measurements to rigorously quantify individual exposures. Other important criteria for biodosimetry methods include obtaining samples with minimal invasiveness, low detection limits, and high precision. Cost and other practical limitations generally prohibit biodosimetry measurements on a large enough sample to replace analytical dose reconstruction in epidemiologic investigations. However, these measurements can be extremely valuable as a means to corroborate analytical or model-based dose estimates, to help reduce uncertainty in individual doses estimated by other methods and techniques, and to assess bias in dose reconstruction models. There has been extensive use of three biodosimetric techniques in irradiated populations: EPR (using tooth enamel), FISH (using blood lymphocytes), and GPA (also using blood); these methods have been supplemented with luminescent methods applied to building materials and artifacts. A large number of investigations have used biodosimetric methods many years after external and, to a lesser extent, internal exposure to reconstruct doses received from accidents, from occupational exposures, from environmental releases of radioactive materials, and from medical exposures. In most applications, the intent has been to either identify highly exposed persons or confirmed suspected exposures. Improvements in methodology, however, have led many investigators to attempt quantification of whole-body doses received, or in a few instances, to estimate organ doses. There will be a continued need for new and improved biodosimetric techniques not only to assist in future epidemiologic investigations but to help evaluate the long-term consequences following nuclear accidents or events of radiologic terrorism.
    Radiation Measurements 07/2007; DOI:10.1016/j.radmeas.2007.05.036 · 1.14 Impact Factor