SOURCES AND EFFECTS OF IONIZING RADIATION : United Nations Scientific Committee on the Effects of Atomic Radiation UNSCEAR 2000 Report to the General Assembly, with Scientific Annexes

NOTE The report of the Committee without its annexes appears as Official Records of the General Assembly, Sixty-third Session, Supplement No. 46. The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The country names used in this document are, in most cases, those that were in use at the time the data were collected or the text prepared. In other cases, however, the names have been updated, where this was possible and appropriate, to reflect political changes. Scientific Annexes Annex A. Medical radiation exposures Annex B. Exposures of the public and workers from various sources of radiation INTROdUCTION 1. In the course of the research and development for and the application of atomic energy and nuclear technologies, a number of radiation accidents have occurred. Some of these accidents have resulted in significant health effects and occasionally in fatal outcomes. The application of technologies that make use of radiation is increasingly widespread around the world. Millions of people have occupations related to the use of radiation, and hundreds of millions of individuals benefit from these uses. Facilities using intense radiation sources for energy production and for purposes such as radiotherapy, sterilization of products, preservation of foodstuffs and gamma radiography require special care in the design and operation of equipment to avoid radiation injury to workers or to the public. Experience has shown that such technology is generally used safely, but on occasion controls have been circumvented and serious radiation accidents have ensued. 2. Reviews of radiation exposures from accidents have been presented in previous UNSCEAR reports. The last report containing an exclusive chapter on exposures from accidents was the UNSCEAR 1993 Report [U6]. 3. This annex is aimed at providing a sound basis for conclusions regarding the number of significant radiation accidents that have occurred, the corresponding levels of radiation exposures and numbers of deaths and injuries, and the general trends for various practices. Its conclusions are to be seen in the context of the Committee's overall evaluations of the levels and effects of exposure to ionizing radiation. 4. The Committee's evaluations of public, occupational and medical diagnostic exposures are mostly concerned with chronic exposures of …

sources and effects of ionizing radiation

This report provides a review of early and late effects of radiation in normal tissues and organs with respect to radiation protection. It was instigated following a recommendation in Publication 103 (ICRP, 2007), and it provides updated estimates of 'practical' threshold doses for tissue injury defined at the level of 1% incidence. Estimates are given for morbidity and mortality endpoints in all organ systems following acute, fractionated, or chronic exposure. The organ systems comprise the haematopoietic, immune, reproductive, circulatory, respiratory, musculoskeletal, endocrine, and nervous systems; the digestive and urinary tracts; the skin; and the eye. Particular attention is paid to circulatory disease and cataracts because of recent evidence of higher incidences of injury than expected after lower doses; hence, threshold doses appear to be lower than previously considered. This is largely because of the increasing incidences with increasing times after exposure. In the context of protection, it is the threshold doses for very long follow-up times that are the most relevant for workers and the public; for example, the atomic bomb survivors with 40-50years of follow-up. Radiotherapy data generally apply for shorter follow-up times because of competing causes of death in cancer patients, and hence the risks of radiation-induced circulatory disease at those earlier times are lower. A variety of biological response modifiers have been used to help reduce late reactions in many tissues. These include antioxidants, radical scavengers, inhibitors of apoptosis, anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, growth factors, and cytokines. In many cases, these give dose modification factors of 1.1-1.2, and in a few cases 1.5-2, indicating the potential for increasing threshold doses in known exposure cases. In contrast, there are agents that enhance radiation responses, notably other cytotoxic agents such as antimetabolites, alkylating agents, anti-angiogenic drugs, and antibiotics, as well as genetic and comorbidity factors. Most tissues show a sparing effect of dose fractionation, so that total doses for a given endpoint are higher if the dose is fractionated rather than when given as a single dose. However, for reactions manifesting very late after low total doses, particularly for cataracts and circulatory disease, it appears that the rate of dose delivery does not modify the low incidence. This implies that the injury in these cases and at these low dose levels is caused by single-hit irreparable-type events. For these two tissues, a threshold dose of 0.5Gy is proposed herein for practical purposes, irrespective of the rate of dose delivery, and future studies may elucidate this judgement further.

https://journals.sagepub.com/doi/pdf/10.1016/j.icrp.2012.02.001

ICRP PUBLICATION 118: ICRP Statement on Tissue Reactions and Early and Late Effects of Radiation in Normal Tissues and Organs – Threshold Doses for Tissue Reactions in a Radiation Protection Context

GUEST EDITORIAL PART I: ICRP STATEMENT ON TISSUE REACTIONS PART II: EARLY AND LATE EFFECTS OF RADIATION IN NORMAL TISSUES AND ORGANS - THRESHOLD DOSES FOR TISSUE REACTIONS IN A RADIATION PROTECTION CONTEXT ABSTRACT PREFACE EXECUTIVE SUMMARY GLOSSARY 1. INTRODUCTION 1.1. Purpose of report 1.2. Definition and nature of tissue reactions to ionising radiation 1.3. General principles of radiation effects in cells and tissues 1.4. References 2. RESPONSE OF TISSUES AND ORGANS TO RADIATION 2.1. Haematopoietic and immune systems 2.2. Digestive system 2.3. Reproductive system 2.4. Skin 2.5. Cardiovascular and cerebrovascular systems 2.6. Eye 2.7. Respiratory system 2.8. Urinary tract 2.9. Musculoskeletal system 2.10. Endocrine system 2.11. Nervous system 2.12. References 3. MODIFIERS OF NORMAL TISSUE RESPONSE 3.1. Terminology 3.2. Mechanisms of action 3.3. Influence of modifiers on radiation response in tissue 3.4. References 4. THRESHOLD DOSES IN RELATION TO RADIOSENSITIVITY OF ORGANS AND TISSUES 4.1. Introduction 4.2. Haematopoietic and immune systems 4.3. Digestive system 4.4. Reproductive system 4.5. Skin 4.6. Cardiovascular and cerebrovascular systems 4.7. Eye 4.8. Respiratory system 4.9. Urinary tract 4.10. Musculoskeletal system 4.11. Endocrine system 4.12. Nervous system 4.13. Conclusions 4.14. References ANNEX A. SUMMARY OF STUDIES OF EXPOSURE AND OPACITIES OR CATARACTS

ICRP statement on tissue reactions and early and late effects of radiation in normal tissues and organs -- threshold doses for tissue reactions in a radiation protection context

"Graefe's Archive" is a distinguished international journal that presents original clinical reports and clinically relevant experimental studies. Founded in 1854 by Albrecht von Graefe to serve as a source of useful clinical information and a stimulus for discussion, the journal has published articles by leading ophthalmologists and vision research scientists for more than a century. With peer review by an international Editorial Board and prompt English-language publication, "Graefe's Archive" provides rapid dissemination of clinical and clinically related experimental information.

Graefe's archive for clinical and experimental ophthalmology

For over 30 years, astronauts in Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons and heavy ions and secondary particles produced in collisions with spacecraft and tissue. Large uncertainties exist in the projection of risks of late effects from space radiation such as cancer and cataracts due to the paucity [corrected] of epidemiological data. Here we present epidemiological [corrected] data linking an increased risk of cataracts for astronauts with higher lens doses (>8 mSv) of space radiation relative to other astronauts with lower lens doses (<8 mSv). Our study uses historical data for cataract incidence in the 295 astronauts participating in NASA's Longitudinal Study of Astronaut Health (LSAH) and individual occupational radiation exposure data. These results, while preliminary because of the use of subjective scoring methods, suggest that relatively low doses of space radiation may predispose crew to [corrected] an increased incidence and early appearance of cataracts.

/pdf/space-radiation-and-cataracts-in-astronauts-58z8ihdxcr.pdf

Space radiation and cataracts in astronauts.

Chylack, L. T., Jr., Peterson. L. E., Feiveson, A. H., Wear, M. L., Manuel, F. K., Tung, W. H., Hardy, D. S., Marak, L. J. and Cucinotta, F. A. NASA Study of Cataract in Astronauts (NASCA). Report 1: Cross-Sectional Study of the Relationship of Exposure to Space Radiation and Risk of Lens Opacity. Radiat. Res. 172, 10-20 (2009). The NASA Study of Cataract in Astronauts (NASCA) is a 5-year longitudinal study of the effect of space radiation exposure on the severity/progression of nuclear, cortical and posterior subcapsular (PSC) lens opacities. Here we report on baseline data that will be used over the course of the longitudinal study. Participants include 171 consenting astronauts who flew at least one mission in space and a comparison group made up of three components: (a) 53 astronauts who had not flown in space, (b) 95 military aircrew personnel, and (c) 99 non-aircrew ground-based comparison subjects. Continuous measures of nuclear, cortical and PSC lens opacities were derived from Nidek EAS ...

https://bioone.org/journals/Radiation-Research/volume-172/issue-1/RR1580.1/NASA-Study-of-Cataract-in-Astronauts-NASCA-Report-1/10.1667/RR1580.1.pdf

NASA study of cataract in astronauts (NASCA). Report 1: Cross-sectional study of the relationship of exposure to space radiation and risk of lens opacity.

Objective:Because of anecdotal reports of CO2-related symptoms onboard the International Space Station (ISS), the relationship between CO2 and in-flight headaches was analyzed.Methods:Headache reports and CO2 measurements were obtained, and arithmetic means and single-point maxima were determined fo

Relationship between carbon dioxide levels and reported headaches on the international space station.

INTRODUCTION: Astronauts have sustained musculoskeletal injuries and minor trauma in space, but our knowledge of these injuries is based mainly on anecdotal reports. The purpose of our study was to catalog and analyze all in-flight musculoskeletal injuries occurring throughout the U.S. space program to date. METHODS: A database on in-flight musculoskeletal injuries among U.S. astronauts was generated from records at the Johnson Space Center. RESULTS: A total of 219 in-flight musculoskeletal injuries were identified, 198 occurring in men and 21 in women. Incidence over the course of the space program was 0.021 per flight day for men and 0.015 for women. Hand injuries represented the most common location of injuries, with abrasions and small lacerations representing common manifestations of these injuries. Crew activity in the spacecraft cabin such as translating between modules, aerobic and resistive exercise, and injuries caused by the extravehicular activity (EVA) suit components were the leading causes of musculoskeletal injuries. Exercise-related injuries accounted for an incidence of 0.003 per day and exercise is the most frequent source of injuries in astronauts living aboard the International Space Station (ISS). Interaction with EVA suit components accounted for an incidence of 0.26 injuries per EVA. DISCUSSION: Hand injuries were among the most common events occurring in U.S. astronauts during spaceflight. Identifying the incidence and mechanism of in-flight injuries will allow flight surgeons to quantify the amount of medical supplies needed in the design of next-generation spacecraft. Engineers can use in-flight injury data to further refine the EVA suit and vehicle components. Language: en

Musculoskeletal injuries and minor trauma in space: incidence and injury mechanisms in U.S. astronauts.

Induction of cataracts by occupational exposure in flight crew has been an important topic of interest in aerospace medicine over the past 5 yr, in association with numerous reports of flight-associated disease incidences Due to numerous confounding variables, it has been difficult to determine whether there is increased cataract risk directly caused by interaction with the flight environment, specifically associated with added radiation exposure during flight Military aviator records from the US Air Force (USAF) and US Navy (USN) and US astronauts at NASA's Lyndon B Johnson Space Center were evaluated for the presence, location, and age of diagnosis of cataracts Military aviators with cataracts were found to have a younger average age at onset of their cataracts compared with astronauts with cataracts, however the prevalence of cataracts was found to be higher in astronauts than in military aviators US Air Force and US Navy aviators' cataracts were most commonly located in the posterior subcapsular region of the lens while astronauts' cataracts were most likely to originate in the cortical zone A prospective clinical trial which controls for confounding variables in examination technique, cataract classification, diet, exposure, and pharmacological intervention is needed to determine what percentage of the risk for cataracts is due to radiation, and how to best develop countermeasures to protect flight crews from radiation bioeffects in the future

Mary L. Wear

Papers

Space radiation and cataracts in astronauts.

NASA study of cataract in astronauts (NASCA). Report 1: Cross-sectional study of the relationship of exposure to space radiation and risk of lens opacity.

Relationship between carbon dioxide levels and reported headaches on the international space station.

Musculoskeletal injuries and minor trauma in space: incidence and injury mechanisms in U.S. astronauts.

Cataract formation mechanisms and risk in aviation and space crews.