Occupational Intakes of Radionuclides Part 1 - ICRP

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DRAFT REPORT FOR CONSULTATION
(15) This report series provides revised dose coefficients for occupational intakes
of radionuclides (OIR) replacing the Publication 30 series (ICRP, 1979, 1980, 1981,
1988b) and Publication 68 (ICRP, 1994b).
(16) Data for the interpretation of bioassay measurements are also provided,
replacing Publications 54 and 78 (ICRP, 1988a, 1997b) and consolidating all of the
information needed to interpret the results of bioassay measurements for a particular
radionuclide in a single ICRP publication.
(17) The full data set of the report series is provided as an electronic annex on the
attached CD-ROMs. The printed documents contain a selected set of data and
materials.
(18) Data are presented in a standard format for each element and its radioisotopes.
Tabulated dose coefficients may be used to determine committed effective dose and
committed equivalent doses from a known intake of a radionuclide. Tabulated values
for dose per unit content may be used to assess committed doses directly from
measurements of appropriate bioassay quantities (e.g. radionuclide activity in whole
body or lungs, or daily excretion of a radionuclide in urine or faeces). Similarly,
values of radionuclide activities per unit intake in the body or in daily excreta
samples, presented in tabular and graphical formats, may be used to assess the intake
corresponding to a single bioassay measurement. Committed doses may then be
assessed from the intake using the tabulated dose coefficients. A full description of
the information provided for each element and radioisotope is given in Chapter 7.
(19) The revised dose coefficients, dose per unit content values and reference
bioassay functions have been calculated using the Publication 100 (ICRP, 2006)
Human Alimentary Tract Model (HATM) and a revision of the Publication 66 (ICRP,
1994a) Human Respiratory Tract Model (HRTM) which takes account of more recent
data. The revisions made to the HRTM are described in Section 3.2 of this report. In
addition, information is provided in this report series on absorption to blood
following inhalation and ingestion of different chemical forms of elements and their
radioisotopes, in those cases for which it is currently judged that the data are
sufficient to make specific recommendations. Revisions have been made to many
models for the systemic biokinetics of radionuclides, making them more
physiologically realistic representations of uptake and retention in organs and tissues
and of excretion.
(20) Biokinetic models, reference physiological data, computational phantoms and
radiation transport calculation codes are used for the calculation of dose coefficients
(ICRP, 2007). ICRP publishes dose coefficients for the inhalation or ingestion of
individual radionuclides by workers, giving both equivalent doses to organs and
tissues, and effective dose (ICRP, 1991, 2007). The steps in the calculation (Figure 1)
can be summarised as follows:
By use of the reference biokinetic models, the distribution and retention of
radionuclides in body organs and tissues of the Reference Worker are
determined as a function of time after intake by inhalation or ingestion For
radiation protection purposes, it assumed that all biokinetic parameters of the
Reference Worker are invariant on sex, anatomy, physiology, race and other
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