Ms. Elena Burikova, the Head of the Radiochemistry Group at the Southern Urals Biophysics Institute (SUBI) in Ozyorsk, Russia, spent five days at the USTUR in July 2012. SUBI studies the effects of radiation in workers from the first Russian nuclear facility, Mayak PA. SUBI houses a radiobiological repository that is similar to the USTUR. The Russian Radiobiology Human Tissue Repository (RHTR) contains tissues from 922 deceased Mayak workers, and biological materials from living workers and non-occupationally exposed residents of Ozyorsk (e.g. blood and surgical specimens).1 SUBI’s radiochemistry group analyzes these human tissues to determine the quantity of actinides (such as plutonium and americium).
Purpose of visit
The purpose of Ms. Burikova’s visit was to learn about new technologies that have been implemented by the USTUR’s radiochemistry program, and to consider how they could be utilized at the SUBI radiochemistry laboratory. During the past three years, the USTUR has made a significant effort to expedite the radiochemistry process by purchasing new instruments and implementing state-of-the-art procedures. These investments have increased the laboratory’s sample throughput, and decreased the volume of acid that is needed to digest (dissolve in acid) tissue samples. This has increased productivity, and decreased the cost per sample.
Technical details
Ms. Burikova was particularly interested in two time-saving technologies: microwave tissue digestion, and rapid actinide separation using a vacuum-box system. The USTUR staff demonstrated how a microwave digester could be used to rapidly dissolve soft tissues and bones. The USTUR director, Dr. Tolmachev, and Ms. Burikova discussed the advantages and limitations of microwave digestion. Ms. Elizabeth Thomas demonstrated rapid actinide separation using TEVA-TRU-DGA extraction chromatographic resins on a vacuum-box system. Ms. Burikova was impressed that individual actinides (specifically: plutonium, americium + curium, uranium, and thorium) could be isolated from an acid-dissolved tissue in six hours. The current SUBI method requires several days to complete the separation. In addition, Dr. Tolmachev shared his knowledge and experience with tissue sample dissolution, actinide radiochemical separation, and alpha-spectrometric measurements.
Software demonstration and in-vivo counting facility tour
Dr. Maia Avtandilashvili demonstrated the use of the Integrated Modules for Bioassay Analysis (IMBA) dosimetric software. IMBA is a suite of software modules that is used for biokinetic modeling and internal dose assessment. IMBA can calculate a worker’s intake, the resulting dose to specific organs, the effective dose to the whole body (from internal emitters), etc.
Dr. Tolmachev also organized a tour of the In Vivo Radiobioassay and Research Facility at the Pacific Northwest National Laboratory (PNNL) in Richland. Mr. Tim Lynch briefly described the facility, demonstrated its whole-body counting systems, and had an engaging discussion about 241Am chest counting.
Sponsorship
This visit was requested by Mr. Barrett N. Fountos, Manager of the U.S. Department of Energy’s Russian Health Studies Program, and sponsored by the Joint Coordinating Committee for Radiation Effects Research (JCCRER) Project 2.4, Mayak Worker Dosimetry.
References
- Russian Radiobiological Human Tissue Repository [online]. 2010. Available at: http://rhtr.subi.su/lindex.php. Accessed: 13 September 2012.