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The primary aim of the epidemiologic study of one million U.S. radiation workers and veterans [the Million Worker Study (MWS)] is to provide scientifically valid information on the level of radiation risk when exposures are received gradually over time, and not within seconds as was the case for Japanese atomic-bomb survivors. The primary outcome of the epidemiologic study is cancer mortality but other causes of death such as cardiovascular disease and cerebrovascular disease will be evaluated. The success of the study is tied to the validity of the dose reconstruction approaches to provide realistic estimates of organ-specific radiation absorbed doses that are as accurate and precise as possible and to properly evaluate their accompanying uncertainties. The dosimetry aspects for the MWS are challenging in that they address diverse exposure scenarios for diverse occupational groups being studied over a period of up to 70 y. The dosimetric issues differ among the varied exposed populations that are considered: atomic veterans, U.S. Department of Energy workers exposed to both penetrating radiation and intakes of radionuclides, nuclear power plant workers, medical radiation workers, and industrial radiographers. While a major source of radiation exposure to the study population comes from external gamma- or x-ray sources, for some of the study groups there is a meaningful component of radionuclide intakes that require internal radiation dosimetry assessments. Scientific Committee 6–9 has been established by the National Council on Radiation Protection and Measurements (NCRP) to produce a report on the comprehensive organ dose assessment (including uncertainty analysis) for the MWS. The NCRP dosimetry report will cover the specifics of practical dose reconstruction for the ongoing epidemiologic studies with uncertainty analysis discussions and will be a specific application of the guidance provided in NCRP Report Nos. 158, 163, 164, and 171. The main role of the Committee is to provide guidelines to the various groups of dosimetrists involved in the MWS to ensure that certain dosimetry criteria are considered: calculation of annual absorbed doses in the organs of interest, separation of low and high linear-energy transfer components, evaluation of uncertainties, and quality assurance and quality control. It is recognized that the MWS and its approaches to dosimetry are a work in progress and that there will be flexibility and changes in direction as new information is obtained, both with regard to dosimetry and with regard to the epidemiologic features of the study components. This manuscript focuses on the description of the various components of the MWS, on the available dosimetry results, and on the challenges that have been encountered. It is expected that the Committee will complete its report in 2016.

Despite a longstanding recognition that radiological protection is not only a matter of science, but also ethics, ICRP publications have rarely addressed the ethical foundations of the system of radiological protection explicitly. The purpose of this publication is to describe how the Commission has relied on ethical values, either intentionally or indirectly, in developing the system of radiological protection with the objective of presenting a coherent view of how ethics is part of this system. In so doing, it helps to clarify the inherent value judgements made in achieving the aim of the radiological protection system as underlined by the Commission in Publication 103. Although primarily addressed to the radiological protection community, this publication is also intended to address authorities, operators, workers, medical professionals, patients, the public, and its representatives (e.g. NGOs) acting in the interest of the protection of people and the environment. This publication provides the key steps concerning the scientific, ethical, and practical evolutions of the system of radiological protection since the first ICRP publication in 1928. It then describes the four core ethical values underpinning the present system: beneficence/ non-maleficence, prudence, justice, and dignity. It also discusses how these core ethical values relate to the principles of radiological protection, namely justification, optimisation, and limitation. The publication finally addresses key procedural values that are required for the practical implementation of the system, focusing on accountability, transparency, and inclusiveness. The Commission sees this publication as a founding document to be elaborated further in different situations and circumstances.

Internalization of radionuclides occurs not only by inhalation, ingestion, parenteral injection (i.e., administration of radioactive material for a medical purpose), and direct transdermal absorption, but also by contaminated wounds. In June 2010, a glove-box operator at the U.S. Department of Energy's Savannah River Site sustained a puncture wound while venting canisters containing legacy materials contaminated with Pu. To indicate the canisters had been vented, a flag was inserted into the vent hole. The shaft of the flag penetrated the protective gloves worn by the operator. Initial monitoring performed with a zinc-sulfide alpha detector indicated 300 dpm at the wound site. After being cleared by radiological controls personnel, the patient was taken to the site medical facility where decontamination was attempted and diethylenetriaminepentaacetic acid (DTPA) was administered intravenously within 1.5 h of the incident. The patient was then taken to the Savannah River Site In Vivo Counting Facility where the wound was counted with a Canberra GL 2820 high-purity germanium detector, capable of quantifying contamination by detecting low-energy x rays and gamma rays. In addition to the classic 13, 17, and 20 keV photons associated with Pu, the low-yield (0.04%) 43.5 keV peak was also detected. This indicated a level of wound contamination orders of magnitude above the initial estimate of 300 dpm detected with handheld instrumentation. Trace quantities of Am were also identified via the 59.5 keV peak. A 24 h urine sample collection was begun on day 1 and continued at varying intervals for over a year. The patient underwent a punch biopsy at 3 h postincident (14,000 dpm removed) and excisional biopsies on days 1 and 9 (removal of an additional 3,200 dpm and 3,800 dpm, respectively). The initial post-DTPA urine sample analysis report indicated excretion in excess of 24,000 dpm Pu. Wound mapping was performed in an effort to determine migration from the wound site and indicated minimum local migration. In vivo counts were performed on the liver, axillary lymph nodes, supratrochlear lymph nodes, and skeleton to assess uptake and did not indicate measurable activity. Seventy-one total doses of DTPA were administered at varying frequencies for 317 d post intake. After allowing 100 d for removal of DTPA from the body, five 24 h urine samples were collected and analyzed for dose assessment by using the wound model described in National Council on Radiation Protection and Measurements Report No. 156. The total effective dose averted via physical removal of the contaminant and DTPA administration exceeded 1 Sv, demonstrating that rapid recognition of incident magnitude and prompt medical intervention are critical for dose aversion.

T a b l e s of r a d i a t i o n dose e s t i m a t e s based on t h e Cristy-Eckerman a d u l t male phantom are provided for a number of radiopharmaceuticals commonly used i n n u c l e a r medicine. Radiation dose e s t i m a t e s are l i s t e d for a l l major source organs, and s e v e r a l o t h e r organs of i n t e r e s t . The dose estimates were c a l c u l a t e d using t h e MIRD Technique as implemented i n t h e MIRDOSE3 computer code, developed by t h e Oak Ridge I n s t i t u t e f o r Science and Education, Radiation I n t e r n a l Dose Information Center.I n t h i s code, r e s i d e n c e t i m e s f o r source organs are used w i t h decay data from t h e MIRD Radionuclide D a t a and Decay Schemes t o produce e s t i m a t e s of r a d i a t i o n dose t o organs of standardized phantoms r e p r e s e n t i n g i n d i v i d u a l 6 of d i f f e r e n t ages.The a d u l t male phantom of t h e Cristy-Eckerman phantom series is d i f f e r e n t f r o m t h e U R D 5, or "Reference Man" phantom (Snyder et al. 1969) i n s e v e r a l a s p e c t s , t h e most important of which i s t h e d i f f e r e n c e i n t h e masses and absorbed f r a c t i o n s f o r t h e a c t i v e (red) marrow.The absorbed f r a c t i o n s f o r low energy photons s t r i k i n g t h e marrow are also d i f f e r e n t . Other minor d i f f e r e n c e s e x i s t , but are not l i k e l y t o s i g n i f i c a n t l y a f f e c t dose estimates c a l c u l a t e d with t h e t w o phantoms.Assumptions which support each of t h e dose estimates appears a t t h e bottom of t h e table of e s t i m a t e s f o r a given radiopharmaceutical.I n most cases, t h e model k i n e t i c s or organ r e s i d e n c e times are e x p l i c i t l y given.The r e s u l t s p r e s e n t e d h e r e can e a s i l y be extended t o i n c l u d e o t h e r radiopharmaceuticals o r phantoms.-%-