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This publication presents radionuclide-specific organ and effective dose rate coefficients for members of the public resulting from environmental external exposures to radionuclide emissions of both photons and electrons, calculated using computational phantoms representing the ICRP reference newborn, 1-year-old, 5-year-old, 10-year-old, 15- year-old, and adult males and females. Environmental radiation fields of monoenergetic photon and electron sources were firstly computed using the Monte Carlo radiation transport code PHITS (Particle and Heavy Ion Transport code System) for source geometries representing environmental radionuclide exposures including planar sources on and within the ground at different depths (representing radionuclide ground contamination from fall-out or naturally occurring terrestrial sources), volumetric sources in air (representing a radioactive cloud), and uniformly distributed sources in simulated contaminated water. For the above geometries, the exposed reference individual is considered to be completely within the radiation field. Organ equivalent dose rate coefficients for monoenergetic photons and electrons were next computed employing the PHITS code thus simulating photon and electron interactions within the tissues and organs of the exposed reference individual. For quality assurance purposes, further cross-check calculations were performed using GEANT4, EGSnrc, MCNPX, MCNP6, and the Visible Monte Carlo radiation transport codes. From the monoenergetic values, nuclide-specific effective and organ equivalent dose rate coefficients for several radionuclides for the above environmental exposures were computed using the nuclear decay data from Publication 107. The coefficients are given as dose rates normalised to radionuclide concentrations in environmental media, such as radioactivity concentration, in units of nSv h-1 Bq-1 m-2 or nSv h-1 Bq-1 m-3 and can be re-normalised to ambient dose equivalent (Sv Sv-1) or air kerma (Sv Gy-1). The findings showed that, in general, the smaller the body mass of the phantom, the higher the organ and effective dose due to (1) closer proximity to the source (in the case of ground contamination) and (2) the smaller amount of body shielding of internal organs in the younger and smaller reference phantoms. The difference in effective dose between an adult and an infant is 60-140% at a photon energy of 50 keV, while it is less than 70% above a photon energy of 100 keV, where the smaller differences are observed for air submersion and the largest differences are observed for soil contamination on the surface of the ground. For realistic exposure situations of radionuclide environmental contamination, the difference was found to be more moderate. For example, for radioactive caesium (134Cs, 136Cs, 137Cs/137mBa) deposited on and in the ground, the difference in effective dose between an adult and an infant was in the range of 20-60%, depending on the radioactivity deposition depth within the soil. ICRP routinely solicits comments on most draft documents prior to publication, with the exception of those that are basically compilations of computed values such as specific absorbed fraction values or dose conversion factors.View comments Draft Document

Double-differential neutron yields from a water phantom bombarded by 290-MeV/nucleon and 430-MeV/nucleon carbon ions were measured at production angles of 15°, 30°, 45°, 60°, 75°, and 90°, and angular distributions of neutron yield and dose around the phantom were obtained. The experimental data were compared with the results of the Monte-Carlo simulation code, PHITS. The PHITS results showed a good agreement with the measured data. In addition, we estimated the angular distributions of neutron yield and dose from 0° to 180° including thermal neutrons using PHITS.

A 72-year-old woman was diagnosed with liver dysfunction during a medical examination. An abdominal computed tomography (CT) scan showed multiple nodules in the left lobe, anterior segment, andposterior segment of the liver, leading to a diagnosis of intrahepatic cholangiocarcinoma (ICC). Extended left lobectomy and partial hepatectomy in the anterior and posterior segment with lymph node dissection was performed. At the time of the operation, small nodules on the peritoneum near the stomach were resected; these nodules were diagnosed as peritoneal disseminations of ICC. The histopathological diagnosis was moderately differentiated tubular adenocarcinoma (T4N0M1, Stage IVB). Adjuvant chemotherapy with S-1 was administered for 18 months. Thirty months after the operation, multiple lung metastases were detected by using CT, and chemotherapy with gemcitabine was initiated. Thirty-six months after chemotherapy with gemcitabine, the patient is alive and at home despite her lung metastases, which grew slightly in size. Herein, we report a long-term survival case of ICC with peritoneal dissemination that was successfully treated with surgical resection and adjuvant chemotherapy.