Therapeutic Ionizing Radiation and the Incidence of Basal Cell Carcinoma and Squamous Cell Carcinoma

Total Page:16

File Type:pdf, Size:1020Kb

Therapeutic Ionizing Radiation and the Incidence of Basal Cell Carcinoma and Squamous Cell Carcinoma STUDY Therapeutic Ionizing Radiation and the Incidence of Basal Cell Carcinoma and Squamous Cell Carcinoma Michael D. Lichter, MD; Margaret R. Karagas, PhD; Leila A. Mott, MS; Steven K. Spencer, MD; The´re`se A. Stukel, PhD; E. Robert Greenberg, MD; for the New Hampshire Skin Cancer Study Group Objective: To estimate the relative risk of developing basal tempt was made to review the radiation treatment re- cell carcinoma (BCC) and squamous cell carcinoma (SCC) cords of subjects who reported a history of radio- after receiving therapeutic ionizing radiation. therapy. Overall, an increased risk of both BCC and SCC was found in relation to therapeutic ionizing radiation. Design: Population-based case-control study. Elevated risks were confined to the site of radiation ex- posure (BCC odds ratio, 3.30; 95% confidence interval, Setting: New Hampshire. 1.60-6.81; SCC odds ratio, 2.94; 95% confidence inter- val, 1.30-6.67) and were most pronounced for those ir- Patients: A total of 592 cases of BCC and 289 cases of radiated for acne exposure. For SCC, an association with SCC identified through a statewide surveillance system radiotherapy was observed only among those whose skin and 536 age- and sex-matched controls selected from was likely to sunburn with sun exposure. population lists. Conclusions: These results largely agree with those of Main Outcome Measures: Histologically confirmed previous studies on the risk of BCC in relation to ion- BCC and invasive SCC diagnosed between July 1, 1993, izing radiation exposure. In addition, they suggest that through June 30, 1995, among New Hampshire resi- the risk of SCC may be increased by radiotherapy, dents. especially in individuals prone to sunburn with sun exposure. Results: Information regarding radiotherapy and other factors was obtained through personal interviews. An at- Arch Dermatol. 2000;136:1007-1011 REATMENT WITH prolonged to previous therapeutic ionizing radia- administration of low- tion. We examined risks according to age dose ionizing radiation is at first exposure, time since exposure, con- associated with subse- dition for which irradiation was adminis- quent nonmelanoma skin tered, and site of exposure. We further as- From Nashua Dermatology cancer (NMSC), particularly basal cell car- sessed the frequency and number of T 1 Associates, Nashua, NH cinoma (BCC). Implicated treatments in- treatments, and, for those who were irra- (Dr Lichter), and the Section of clude radiotherapy of inflammatory der- diated for cancer, the amount of expo- Biostatistics and Epidemiology, matoses such as eczema, psoriasis, acne sure by dose per week and by dose per Department of Community and vulgaris, and tinea capitis.2,3 Addition- treatment course. Family Medicine, and the Norris Cotton Cancer Center ally, an increased risk of BCC has been re- (Drs Karagas, Stukel, and lated to ionizing radiation treatment of goi- RESULTS 4 5-8 Greenberg, and Ms Mott), ters, ankylosing spondylitis, acute Section of Dermatology lymphocytic leukemia, and astrocy- By design, cases and controls were compa- (Dr Spencer), Department of toma.9 Whether radiotherapy enhances rable for age and sex. The overall mean age Medicine, Dartmouth Medical risk of squamous cell carcinoma (SCC) is of cases with BCC and SCC was 58.5 years School, Lebanon, NH. The less clear. A population-based study among and 64.7 years, respectively, and 60.5 years authors have no commercial, men in Alberta, Canada, reported a 5- to for controls. About 40% of the subjects were proprietary, or financial 6-fold increase in incidence of BCC and women and 98% were white. Seven per- interests in the products or SCC associated with nondiagnostic x-ray cent of the controls and 12% of the cases companies described in this 10 article. A complete list of the exposure. Using data collected as part of reported previous ionizing radiation therapy members of the New Hampshire a large case-control study in New Hamp- for reasons other than skin cancer. Skin Cancer Study Group shire, we also had the opportunity to evalu- For BCC, we found a significantly in- appears on page 1010. ate the risk of BCC and SCC in relation creased risk associated with radiotherapy (REPRINTED) ARCH DERMATOL / VOL 136, AUG 2000 WWW.ARCHDERMATOL.COM 1007 ©2000 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/24/2021 SUBJECTS AND METHODS history of radiotherapy for skin cancer. Patients treated with ionizing radiation for skin cancer are more likely to be in the case group than in the control group. Therefore, the The case-control study group consisted of patients with BCC inclusion of these cases could bias analyses toward an as- and SCC, aged 25 to 74 years at diagnosis, who were iden- sociation with radiotherapy. We adjusted for age (as a con- tified through a population-based incidence survey of skin tinuous variable) and sex in all models. In addition, we ex- cancer conducted in New Hampshire covering diagnoses amined the potentially confounding effects of outdoor from July 1, 1993, through June 30, 1995.11 Age- and sex- exposure (hours per week spent outdoors in the summer— matched controls were selected from state drivers’ license recreationally and occupationally); cigarette smoking his- lists for those younger than 65 years and from Medicare tory (never, former, current); level of education (less than enrollment lists for those 65 years or older. college, college, graduate or professional school); and sun- An in-person interview that took 90 minutes to 2 hours sensitive skin type defined according to skin reaction to to complete was usually conducted in the subject’s home. strong sunlight for the first time in summer for 1 hour (se- Interviewers were masked to the study hypotheses and were vere sunburn with blistering, painful sunburn, mild sun- not told the case-control status of the participant. Inter- burn and some tanning, and tanning with no sunburn). We viewers asked about sun exposure history, outdoor recre- also explored the possibility that the effects of ionizing ra- ation, skin reaction to sunlight, personal use of tobacco and diation exposure may be modified by skin type. alcohol, educational background, and medical history. To We grouped anatomical location of both skin cancer document previous exposure to therapeutic ionizing ra- and radiation field to the head and neck, trunk, or limbs. diation, we asked subjects if they were ever treated with For controls, we randomly assigned a site based on the ana- x-rays along with the condition and anatomical location tomical distribution of the overall case group. Data were treated, age at and duration of treatment, and the fre- too sparse to study specific anatomical sites of involve- quency of treatments. We requested permission to obtain ment. Therefore, we computed separate ORs for skin can- the medical records of those who reported a history of ra- cers in the radiation field and at unirradiated sites. In this diotherapy. Medical records review was done without analysis, we excluded individuals whose tumor or irradia- knowledge of the subject’s case-control status or other data tion occurred at more than 1 anatomical location. collected at the interview. Lastly, we attempted to analyze the dose per week and We estimated the odds ratio (OR) and 95% confi- the dose per treatment course among those who reported dence intervals (CIs) of BCC and SCC associated with ra- treatment for cancer and for whom irradiation records were diotherapy using unconditional logistic regression.12 We available. Treatment for nonmalignant conditions gener- restricted our analysis to the 592 cases of BCC, 289 cases ally had occurred before 1970; thus, the medical records of SCC, and 536 control subjects who did not have a were no longer available. (age and sex-adjusted OR, 1.88; 95% CI, 1.24-2.87) and The difference between the ORs for the exposed and un- for SCC a borderline significant increased risk (age- and exposed sites was statistically significant for BCC (P=.01) sex-adjusted OR, 1.56; 95% CI, 0.95, 2.55) (Table 1). and borderline significant for SCC (P=.07). When we ex- Adjustment for other potentially confounding factors had amined whether the risks associated with radiotherapy no appreciable effect on the risk estimates. were modified by skin type, we found that for BCC, the The magnitude of the ORs differed according to the ORs for radiation treatment were comparable among those reported reason for treatment. Radiotherapy for acne was who tend to burn and those who tend to tan with first associated with a pronounced and statistically signifi- exposure to sunlight in the summer (among burners, cant increased risk for BCC and SCC (Table 1). A 2-fold OR,1.87; 95% CI, 0.86-4.03 and among tanners, OR, 1.96; increase in BCC risk was found in relation to radio- 95% CI, 1.18-3.26) (P value for interaction, .97). Whereas therapy for cancer, but no increased risk of SCC was found for SCC, risk was increased only among those with a ten- (Table 1). No relation was observed among those who dency to burn (OR, 3.02; 95% CI, 1.37-6.68) and was not had radiotherapy for other benign skin conditions. elevated among those who tend to tan (OR, 0.73; 95% Odds ratios for BCC and SCC according to time since CI, 0.35-1.52) (P value for interaction, .01). the initial exposure and age first treated with radiation Medical records were reviewed for 44 (79%) of the are given in Table 1. Persons whose first radiation treat- 56 subjects who reported receiving therapeutic ionizing ment occurred before they were 20 years old had a greater radiation for cancer. Of the 39 patients receiving radia- risk of BCC and SCC than those treated at older ages.
Recommended publications
  • Nuclear Energy in Everyday Life Nuclear Energy in Everyday Life
    Nuclear Energy in Everyday Life Nuclear Energy in Everyday Life Understanding Radioactivity and Radiation in our Everyday Lives Radioactivity is part of our earth – it has existed all along. Naturally occurring radio- active materials are present in the earth’s crust, the floors and walls of our homes, schools, and offices and in the food we eat and drink. Our own bodies- muscles, bones and tissues, contain naturally occurring radioactive elements. Man has always been exposed to natural radiation arising from earth as well as from outside. Most people, upon hearing the word radioactivity, think only about some- thing harmful or even deadly; especially events such as the atomic bombs that were dropped on Hiroshima and Nagasaki in 1945, or the Chernobyl Disaster of 1986. However, upon understanding radiation, people will learn to appreciate that radia- tion has peaceful and beneficial applications to our everyday lives. What are atoms? Knowledge of atoms is essential to understanding the origins of radiation, and the impact it could have on the human body and the environment around us. All materi- als in the universe are composed of combination of basic substances called chemical elements. There are 92 different chemical elements in nature. The smallest particles, into which an element can be divided without losing its properties, are called atoms, which are unique to a particular element. An atom consists of two main parts namely a nu- cleus with a circling electron cloud. The nucleus consists of subatomic particles called protons and neutrons. Atoms vary in size from the simple hydro- gen atom, which has one proton and one electron, to large atoms such as uranium, which has 92 pro- tons, 92 electrons.
    [Show full text]
  • Sources, Effects and Risks of Ionizing Radiation
    SOURCES, EFFECTS AND RISKS OF IONIZING RADIATION United Nations Scientific Committee on the Effects of Atomic Radiation UNSCEAR 2016 Report to the General Assembly, with Scientific Annexes UNITED NATIONS New York, 2017 NOTE The report of the Committee without its annexes appears as Official Records of the General Assembly, Seventy-first Session, Supplement No. 46 and corrigendum (A/71/46 and Corr.1). The report reproduced here includes the corrections of the corrigendum. 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. UNITED NATIONS PUBLICATION Sales No. E.17.IX.1 ISBN: 978-92-1-142316-7 eISBN: 978-92-1-060002-6 © United Nations, January 2017. All rights reserved, worldwide. This publication has not been formally edited. Information on uniform resource locators and links to Internet sites contained in the present publication are provided for the convenience of the reader and are correct at the time of issue. The United Nations takes no responsibility for the continued accuracy of that information or for the content of any external website.
    [Show full text]
  • Radiation and Risk: Expert Perspectives Radiation and Risk: Expert Perspectives SP001-1
    Radiation and Risk: Expert Perspectives Radiation and Risk: Expert Perspectives SP001-1 Published by Health Physics Society 1313 Dolley Madison Blvd. Suite 402 McLean, VA 22101 Disclaimer Statements and opinions expressed in publications of the Health Physics Society or in presentations given during its regular meetings are those of the author(s) and do not necessarily reflect the official position of the Health Physics Society, the editors, or the organizations with which the authors are affiliated. The editor(s), publisher, and Society disclaim any responsibility or liability for such material and do not guarantee, warrant, or endorse any product or service mentioned. Official positions of the Society are established only by its Board of Directors. Copyright © 2017 by the Health Physics Society All rights reserved. No part of this publication may be reproduced or distributed in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed in the United States of America SP001-1, revised 2017 Radiation and Risk: Expert Perspectives Table of Contents Foreword……………………………………………………………………………………………………………... 2 A Primer on Ionizing Radiation……………………………………………………………………………... 6 Growing Importance of Nuclear Technology in Medicine……………………………………….. 16 Distinguishing Risk: Use and Overuse of Radiation in Medicine………………………………. 22 Nuclear Energy: The Environmental Context…………………………………………………………. 27 Nuclear Power in the United States: Safety, Emergency Response Planning, and Continuous Learning…………………………………………………………………………………………….. 33 Radiation Risk: Used Nuclear Fuel and Radioactive Waste Disposal………………………... 42 Radiation Risk: Communicating to the Public………………………………………………………… 45 After Fukushima: Implications for Public Policy and Communications……………………. 51 Appendix 1: Radiation Units and Measurements……………………………………………………. 57 Appendix 2: Half-Life of Some Radionuclides…………………………………………………………. 58 Bernard L.
    [Show full text]
  • Nuclear Fusion Enhances Cancer Cell Killing Efficacy in a Protontherapy Model
    Nuclear fusion enhances cancer cell killing efficacy in a protontherapy model GAP Cirrone*, L Manti, D Margarone, L Giuffrida, A. Picciotto, G. Cuttone, G. Korn, V. Marchese, G. Milluzzo, G. Petringa, F. Perozziello, F. Romano, V. Scuderi * Corresponding author Abstract Protontherapy is hadrontherapy’s fastest-growing modality and a pillar in the battle against cancer. Hadrontherapy’s superiority lies in its inverted depth-dose profile, hence tumour-confined irradiation. Protons, however, lack distinct radiobiological advantages over photons or electrons. Higher LET (Linear Energy Transfer) 12C-ions can overcome cancer radioresistance: DNA lesion complexity increases with LET, resulting in efficient cell killing, i.e. higher Relative Biological Effectiveness (RBE). However, economic and radiobiological issues hamper 12C-ion clinical amenability. Thus, enhancing proton RBE is desirable. To this end, we exploited the p + 11Bà3a reaction to generate high-LET alpha particles with a clinical proton beam. To maximize the reaction rate, we used sodium borocaptate (BSH) with natural boron content. Boron-Neutron Capture Therapy (BNCT) uses 10B-enriched BSH for neutron irradiation-triggered alpha-particles. We recorded significantly increased cellular lethality and chromosome aberration complexity. A strategy combining protontherapy’s ballistic precision with the higher RBE promised by BNCT and 12C-ion therapy is thus demonstrated. 1 The urgent need for radical radiotherapy research to achieve improved tumour control in the context of reducing the risk of normal tissue toxicity and late-occurring sequelae, has driven the fast- growing development of cancer treatment by accelerated beams of charged particles (hadrontherapy) in recent decades (1). This appears to be particularly true for protontherapy, which has emerged as the most-rapidly expanding hadrontherapy approach, totalling over 100,000 patients treated thus far worldwide (2).
    [Show full text]
  • Positron Emission Tomography
    Positron emission tomography A.M.J. Paans Department of Nuclear Medicine & Molecular Imaging, University Medical Center Groningen, The Netherlands Abstract Positron Emission Tomography (PET) is a method for measuring biochemical and physiological processes in vivo in a quantitative way by using radiopharmaceuticals labelled with positron emitting radionuclides such as 11C, 13N, 15O and 18F and by measuring the annihilation radiation using a coincidence technique. This includes also the measurement of the pharmacokinetics of labelled drugs and the measurement of the effects of drugs on metabolism. Also deviations of normal metabolism can be measured and insight into biological processes responsible for diseases can be obtained. At present the combined PET/CT scanner is the most frequently used scanner for whole-body scanning in the field of oncology. 1 Introduction The idea of in vivo measurement of biological and/or biochemical processes was already envisaged in the 1930s when the first artificially produced radionuclides of the biological important elements carbon, nitrogen and oxygen, which decay under emission of externally detectable radiation, were discovered with help of the then recently developed cyclotron. These radionuclides decay by pure positron emission and the annihilation of positron and electron results in two 511 keV γ-quanta under a relative angle of 180o which are measured in coincidence. This idea of Positron Emission Tomography (PET) could only be realized when the inorganic scintillation detectors for the detection of γ-radiation, the electronics for coincidence measurements, and the computer capacity for data acquisition and image reconstruction became available. For this reason the technical development of PET as a functional in vivo imaging discipline started approximately 30 years ago.
    [Show full text]
  • Radiation and Your Patient: a Guide for Medical Practitioners
    RADIATION AND YOUR PATIENT: A GUIDE FOR MEDICAL PRACTITIONERS A web module produced by Committee 3 of the International Commission on Radiological Protection (ICRP) What is the purpose of this document ? In the past 100 years, diagnostic radiology, nuclear medicine and radiation therapy have evolved from the original crude practices to advanced techniques that form an essential tool for all branches and specialties of medicine. The inherent properties of ionising radiation provide many benefits but also may cause potential harm. In the practice of medicine, there must be a judgement made concerning the benefit/risk ratio. This requires not only knowledge of medicine but also of the radiation risks. This document is designed to provide basic information on radiation mechanisms, the dose from various medical radiation sources, the magnitude and type of risk, as well as answers to commonly asked questions (e.g radiation and pregnancy). As a matter of ease in reading, the text is in a question and answer format. Interventional cardiologists, radiologists, orthopaedic and vascular surgeons and others, who actually operate medical x-ray equipment or use radiation sources, should possess more information on proper technique and dose management than is contained here. However, this text may provide a useful starting point. The most common ionising radiations used in medicine are X, gamma, beta rays and electrons. Ionising radiation is only one part of the electromagnetic spectrum. There are numerous other radiations (e.g. visible light, infrared waves, high frequency and radiofrequency electromagnetic waves) that do not posses the ability to ionize atoms of the absorbing matter.
    [Show full text]
  • Literature Survey on Decorporation of Radionuclides from the Human Body
    Literature Survey on Decorporation of Radionuclides from the Human Body E.A. Waller, R.Z. Stodilka, K. Leach and L. Prud’homme-Lalonde Defence R&D Canada - Ottawa TECHNICAL MEMORANDUM DRDC Ottawa TM 2002-042 April 2002 Literature Survey on Decorporation of Radionuclides from the Human Body E.A. Waller SAIC Canada, Inc R.Z. Stodilka, K. Leach and L. Prud’homme-Lalonde Space Systems and Technology Defence R&D Canada - Ottawa Technical Memorandum DRDC Ottawa TM 2002-042 April 2002 © Her Majesty the Queen as represented by the Minister of National Defence, 2002 © Sa majesté la reine, représentée par le ministre de la Défense nationale, 2002 Abstract The broad use of radionuclides by many industries has greatly increased the probability of events that could lead to internalized contamination. Examples include accidents and/or intentional damage to nuclear power plants or radiation therapy units in hospitals, the use of radiological dispersal weapons, and lost or stolen radionuclide sources. Developing effective countermeasures requires knowledge of the physical and chemical composition of the radionuclides, their metabolic activities within the body, and methods to expedite their elimination from the body. This report presents a summary of information pertaining to intake and decorporation of radionuclides from humans. This information would be the first step in establishing a field protocol to guide physicians in military missions. Developing such a guide requires an understanding of the dangers associated with internal radioisotope contamination, decision levels for administering therapy (risk vs. benefit) and protocols for administering therapy. As presented, this study could be used to decide what decorporation pharmaceuticals should be maintained in quantity by the military, and how to best train officers with medical responsibilities.
    [Show full text]
  • And Stereotactic Body Radiation Therapy (SBRT)
    Geisinger Health Plan Policies and Procedure Manual Policy: MP084 Section: Medical Benefit Policy Subject: Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy I. Policy: Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT) II. Purpose/Objective: To provide a policy of coverage regarding Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT) III. Responsibility: A. Medical Directors B. Medical Management IV. Required Definitions 1. Attachment – a supporting document that is developed and maintained by the policy writer or department requiring/authoring the policy. 2. Exhibit – a supporting document developed and maintained in a department other than the department requiring/authoring the policy. 3. Devised – the date the policy was implemented. 4. Revised – the date of every revision to the policy, including typographical and grammatical changes. 5. Reviewed – the date documenting the annual review if the policy has no revisions necessary. V. Additional Definitions Medical Necessity or Medically Necessary means Covered Services rendered by a Health Care Provider that the Plan determines are: a. appropriate for the symptoms and diagnosis or treatment of the Member's condition, illness, disease or injury; b. provided for the diagnosis, and the direct care and treatment of the Member's condition, illness disease or injury; c. in accordance with current standards of good medical treatment practiced by the general medical community. d. not primarily for the convenience of the Member, or the Member's Health Care Provider; and e. the most appropriate source or level of service that can safely be provided to the Member. When applied to hospitalization, this further means that the Member requires acute care as an inpatient due to the nature of the services rendered or the Member's condition, and the Member cannot receive safe or adequate care as an outpatient.
    [Show full text]
  • New Discoveries in Radiation Science
    cancers Editorial New Discoveries in Radiation Science Géza Sáfrány 1,*, Katalin Lumniczky 1 and Lorenzo Manti 2 1 Department Radiobiology and Radiohygiene, National Public Health Center, 1221 Budapest, Hungary; [email protected] 2 Department of Physics, University of Naples Federico II, 80126 Naples, Italy; [email protected] * Correspondence: [email protected]; Tel.: +36-309199218 This series of 16 articles (8 original articles and 8 reviews) was written by internation- ally recognized scientists attending the 44th Congress of the European Radiation Research Society (Pécs, Hungary). Ionizing radiation is an interesting agent because it is used to cure cancers and can also induce cancer. The effects of ionizing radiation at the organism level depend on the response of the cells. When radiation hits a cell, it might damage any cellular organelles and macromolecules. Unrepairable damage leads to cell death, while misrepaired alterations leave mutations in surviving cells. If the repair is errorless, normal cells will survive. However, in a small percentage of the seemingly healthy cells the number of spontaneous mutations will increase, which is a sign of radiation-induced genomic instability. Radiation-induced cell death is behind the development of acute radiation syndromes and the killing of tumorous and normal cells during radiation therapy. Radiation-induced mutations in surviving cells might lead to the induction of tumors. According to the central paradigm of radiation biology, the genetic material, that is the DNA, is the main cellular target of ionizing radiation. Many different types of damage are induced by radiation in the DNA, but the most deleterious effects arise from double strand breaks (DSBs).
    [Show full text]
  • Radiation Therapy
    Radiation Therapy What is radiation therapy? Radiation therapy is the use of high-energy x-rays or other particles to destroy cancer cells. A doctor who uses radiation therapy to treat cancer is called a radiation oncologist. The goal of radiation therapy is to destroy the cancer cells without harming nearby healthy tissue. It may be used along with other cancer treatments or as the main treatment. Sometimes radiation therapy is used to relieve symptoms, called palliative radiation therapy. More than half of all people with cancer receive some type of radiation therapy. What are the different types of radiation therapy? The most common type is called external-beam radiation therapy, which is radiation given from a machine located outside the body. Types of external-beam radiation therapy include proton therapy, 3-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and stereotactic radiation therapy. Sometimes radiation therapy involves bringing a radioactive source close to a tumor. This is called internal radiation therapy or brachytherapy. The type you receive depends on many factors. Learn more about radiation treatment at www.cancer.net/radiationtherapy. What should I expect during radiation therapy? Before treatment begins, you will meet with the radiation oncologist to review your medical history and discuss the potential risks and benefits. If you choose to receive radiation therapy, you may undergo tests to plan the treatment and evaluate the results. Before radiation therapy begins, it must be planned carefully. This planning stage is often called a “simulation.” During this visit, the medical team will figure out the best position for you to be in during treatment.
    [Show full text]
  • Toxicological Profile for Plutonium
    PLUTONIUM A-1 APPENDIX A. ATSDR MINIMAL RISK LEVELS AND WORKSHEETS The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) [42 U.S.C. 9601 et seq.], as amended by the Superfund Amendments and Reauthorization Act (SARA) [Pub. L. 99– 499], requires that the Agency for Toxic Substances and Disease Registry (ATSDR) develop jointly with the U.S. Environmental Protection Agency (EPA), in order of priority, a list of hazardous substances most commonly found at facilities on the CERCLA National Priorities List (NPL); prepare toxicological profiles for each substance included on the priority list of hazardous substances; and assure the initiation of a research program to fill identified data needs associated with the substances. The toxicological profiles include an examination, summary, and interpretation of available toxicological information and epidemiologic evaluations of a hazardous substance. During the development of toxicological profiles, Minimal Risk Levels (MRLs) are derived when reliable and sufficient data exist to identify the target organ(s) of effect or the most sensitive health effect(s) for a specific duration for a given route of exposure. An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over a specified duration of exposure. MRLs are based on noncancer health effects only and are not based on a consideration of cancer effects. These substance-specific estimates, which are intended to serve as screening levels, are used by ATSDR health assessors to identify contaminants and potential health effects that may be of concern at hazardous waste sites.
    [Show full text]
  • A Framework for Quality Radiation Oncology Care
    Safety is No Accident A FRAMEWORK FOR QUALITY RADIATION ONCOLOGY CARE DEVELOPED AND SPONSORED BY Safety is No Accident A FRAMEWORK FOR QUALITY RADIATION ONCOLOGY CARE DEVELOPED AND SPONSORED BY: American Society for Radiation Oncology (ASTRO) ENDORSED BY: American Association of Medical Dosimetrists (AAMD) American Association of Physicists in Medicine (AAPM) American Board of Radiology (ABR) American Brachytherapy Society (ABS) American College of Radiology (ACR) American Radium Society (ARS) American Society of Radiologic Technologists (ASRT) Society of Chairmen of Academic Radiation Oncology Programs (SCAROP) Society for Radiation Oncology Administrators (SROA) T A R G E T I N G CAN CER CAR E The content in this publication is current as of the publication date. The information and opinions provided in the book are based on current and accessible evidence and consensus in the radiation oncology community. However, no such guide can be all-inclusive, and, especially given the evolving environment in which we practice, the recommendations and information provided in the book are subject to change and are intended to be updated over time. This book is made available to ASTRO and endorsing organization members and to the public for educational and informational purposes only. Any commercial use of this book or any content in this book without the prior written consent of ASTRO is strictly prohibited. The information in the book presents scientific, health and safety information and may, to some extent, reflect ASTRO’s and the endorsing organizations’ understanding of the consensus scientific or medical opinion. ASTRO and the endorsing organizations regard any consideration of the information in the book to be voluntary.
    [Show full text]