U.S. Transuranium and Uranium Registries
Conducting a multi-faced program that studies the biokinetics and dosimetry of the
actinide elements in humans, the USTUR is a major contributor to radiological
protection guidelines and methodologies for assessing human exposure to these
radioactive elements. This is important to DOE because the occupational exposures
of DOE workers continue to include the potential for internal deposition of materials
containing uranium and plutonium through inhalation, ingestion or injection. Doses
from these depositions cannot be directly measured, but are calculated from a variety
of measurements, techniques, and computer models.
Radiochemical analyses of tissues voluntarily donated posthumously by
occupationally-exposed USTUR registrants reveal how plutonium
and uranium are metabolized and distributed through the body. USTUR combines this
information with data from each registrant's employment, exposure, and medical
histories to have a comprehensive set of real-life, human data that are used to
develop and improve internal dosimetry modeling approaches that are applicable
to radiation workers, as well as for members of the public who may be exposed
during an accidental or intentional radiological dispersal event.
The National Human Radiology Tissue Repository (NHRTR) and the
National Radiobiology Archive (NRA), for animal tissues, are two
additional USTUR components that provide stewardship of specialized
collections of human or animal tissues, histopathology slides, and research
materials related to USTUR and other DOE-sponsored radiation studies.
These materials are preserved, catalogued and made available to
qualified scientists wishing to perform actinide micro-distribution
or molecular studies utilizing deeply frozen tissues containing
plutonium or uranium.
Supported by a DOE grant to Washington State University,
USTUR embodies a unique combination of capabilities and facilities
in an academic setting that provides opportunity for students and
university personnel to participate in USTUR research and specialized
analytical projects. Additionally, the Registries are guided by an
external Scientific Advisory Committee, comprised of seven individuals
with expertise in pertinent disciplines. Oversight by this Committee
and interaction with academics ensure the quality and independence of
USTUR research. The USTUR web site at
http://www.ustur.wsu.edu provides access to USTUR reports and much
more information about the project.
Accomplishments: The following accomplishments directly
support USTUR's mission of providing independent, continuous improvement
in techniques used to estimate internal doses attributable to intakes
of long-lived radioactive materials. This will help ensure that
radiological protection standards and dosimetry models are protective
of worker health.
- In June, USTUR published a new website that includes information of
general interest about USTUR, the history of the Registries and Advisory
Committees, and also "News" of special USTUR events and research progress.
USTUR is working hard to publish on this site all of its radiochemistry and
health physics data, with a summary description of every Registrant case study.
- During the past 38 years, USTUR has performed about 20,000 radio-chemical
analyses on hundreds of autopsy samples donated by nearly 400 Registrants
to form the basis for many technical reports, with more than 150 papers
being published in peer-reviewed, scientific literature.
- With 105 Registrants between the ages of 35 and 96 years-old, USTUR will obtain additional
data that will continue to improve and narrow the uncertainties associated
with dose assessment. This could result in less conservative risk assumptions
and in a reduction of costs for engineering controls needed to prevent
occupational exposures to the actinide elements.
- Provided data and expertise in verifying and refining a suite of software
programs that implement state-of-the-art methodologies for assessing internal
doses incurred by DOE workers across the complex.
- Attracted a nationally and internationally recognized expert in the field
of internal dose assessment and actinide biokinetic research to serve as
Principal Investigator for the grant's renewed (5-year) cycle. He is moving
USTUR more strongly into quantitative modeling approaches for data analyses
and will use USTUR's growing number of donated tissues to determine human
inter-subject variability in key transfer rates within the dosimetric models
used to determine tissue doses and health risk.
- Began developing a dosimetry model that better mechanically represents
the effects of chelation therapy on the biokinetics of actinide elements in
humans. This is especially timely because chelation therapy may be used after
accidents or terrorist events. Contributing to USTUR's ability to fill this
significant gap in knowledge of actinide element dosimetry will be the
hundreds of additional radiochemical tissue analyses from three additional
whole bodies expected to be donated by Registrants in the next few years.
LINKS
DOE Liaison: Marsha Lawn
Related Documents & Links
This page was last updated on February 08, 2008
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