Occupational Intakes of Radionuclides Part 1 - ICRP

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DRAFT REPORT FOR CONSULTATION
3 BIOKINETIC AND DOSIMETRIC MODELS
3.1 Introduction
(82) This chapter gives an overview of the biokinetic and dosimetric models used
to calculate dose coefficients and bioassay data. It explains the changes made here to
the Human Respiratory Tract Model (HRTM) (ICRP, 1994a) and describes the main
features of the Human Alimentary Tract Model (HATM) (ICRP, 2006). It also
provides an introduction to the models used in this series of reports to describe the
systemic biokinetics of elements and their radioisotopes. Dosimetric models and
methodology are also explained.
(83) Radionuclide exposures in the workplace can lead to intakes by a number of
routes: inhalation, ingestion, entry through intact skin and wounds. Figure 2
summarises the routes of intake, internal transfers, and routes of excretion.
(84)
Wound
Sweat
Skin
Skin
Lymph nodes
Subcutaneous
tissue
Direct absorption
Extrinsic removal
Inhalation Exhalation Ingestion
Respiratory
tract
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Blood
Other organs Kidney
Liver
Urinary bladder
Gastrointestinal
tract
Urine Faeces
Figure 2. Summary of the main routes of intake, transfer and excretion of radionuclides in
the body
(85) For inhalation, the HRTM (ICRP, 1994a) was applied in Publication 68
(ICRP, 1994b) and in subsequent publications on dose coefficients (ICRP, 1995c,
1996). For these implementations of the HRTM, chemical forms of radionuclides that