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Indian Health Service Rotation. Natalie Branagan August 28 th , 2007. HPI.
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Indian Health Service Rotation Natalie Branagan August 28th, 2007
HPI • 72 yo man referred to the Radiation Exposure Screening and Education Program clinic for positive review of systems on hospital screening – reported shortness of breath and has a history of working in the uranium mines.
HPI • The patient reports that he has had shortness of breath beginning about 9 months ago. • Unable to walk greater then 50 feet. • No orthopnea, no lower extremity edema • Reports occasional chest pain • No cough, no fevers or chills
HPI • Worked in two uranium mines from 1958 – 1959 • Worked underground and above ground dumping mining waste material • Sometimes wore a mask • Stopped mining after falling at work – sustained a fracture to right arm and hit his head • Recounts how electricity was lost for approximately one hour while working in mines once – mechanical ventilator and elevators stopped working during that time.
Past medical history • Coronary artery disease • Status post CABG 11/06 • Hypertension • CVA in 10/06 • Residual left sided hemianopsia and difficulty speaking clearly • Bilateral carotid bruits diagnosed 2000 • Refused workup at that time
Medications • Aspirin 325 mg daily • Atenolol 25 mg daily • Multivitamin • Allergies: NKDA
Family history • Mother and father deceased of unknown causes in their 80’s • No known family history of hypertension, diabetes, CVA or myocardial infarction
Social history • Lives with wife • Retired currently • Worked as a bus driver after working in mines up until about 1 year ago • Owns sheep and cattle • Denies smoking, alcohol or drug use
Review of systems • Reports unable to see out of left eye since CVA • Also reports difficulty with memory ever since falling and hitting head in the mines • Occasional palpitations • No abdominal pain, nausea, vomiting, dysuria
Physical exam • Vitals: T 98.0, P 82, BP 164/96, RR 16, 94% on room air, weight 77.7 kg, height 65 inches • Gen: elderly appearing Native American man in no acute distress • HEENT: PERRL, mucus membranes moist, no lesions • Neck: no jugular venous distention, no cervical nodes • c/v: regular rate and rhythm, normal s1 and s2, no murmurs, rubs or gallups • Pulm: fine crackles at bases bilaterally, no dullness to percussion • Abd: soft, not tender, not distended, no hepatosplenomegaly, normoactive bowel sounds • Extremities: no cyanosis, clubbing or edema, 2+ peripheral pulses
Labs and studies • ABG 7.42/34/51/-1.6/21.7/85.4% with FI02 of 21% • PFTs • FVC 3.72 Liters (54%) • FEV1 2.89 Liters (61%) • FEV1/FVC 0.78 (113%) • FEF 25% 6.50 (91%) • FEF 75% 1.02 L (100%) • FEF 25-75% 2.77 (86%) • FEF max 7.07 89% • Hgb 15.7 g/dL
Chest x-ray • s/p CABG, slight cardiomegaly, pulmonary vasculature normal, no infiltrate or pleural effusion, degenerative changes in the spine
Uranium • Found at low concentrations naturally in soil, round, surface water and ground water • Radioactive • Several isotopes, however U238 is predominant isotope in naturally occurring uranium • Half-life of U238 is 4.5 billion years
Uranium • Primary use is as fuel in nuclear power reactors to make electricity • Highly enriched uranium is a component of nuclear weapons • Uranium ore is usually found in hard rock or sandstone
Uranium mining history • 1948 the US Atomic Energy Commission began to purchase all uranium mined in the US • Uranium mining became a large industry in Utah, Arizona, New Mexico and Colorado • Uranium mining peaked in the 1950’s with over 750 mines operating • Approximately 3,000 uranium miners were Navajo
Uranium demand increasing Western World Uranium Production and Demand 1945-2004 www.uic.com
Uranium mining • Underground mining • Involves drilling of shafts into sandstone, blasting, loading ore into bins and transporting ore up via elevators • Miners were exposed to large amounts of dust and smoke after re-entering the mines after blasting
Uranium mining and milling • Uranium ore contains between 0.5 -2% of uranium oxide • Milling is the process in which uranium oxide is extracted from the uranium ore • Involves crushing the mined ore, mixing it with water and adding chemicals such as sulfuric acid to separate out of the uranium ore, the liquid is then filtered from the rest of the material, and is concentrated by precipitation and then dried.
Health effects of uranium mining • Degenerative joint disease • From repetitive motion • Trauma • As result of crush injuries from heavy equipment or falling rock • Hearing impairment • From drilling and blasting • Diseases of the lungs • Exposure to dusts, fumes and gases can cause malignant and nonmalignant diseases Mulloy, K et. al. Environmental Health Perspectives 2001;305-309
Nonmalignant lung processes • Pneumoconiosis • Lung diseases caused by the inhalation of dust • Silicosis • Pulmonary diseases caused by the inhalation of silica • Diffuse fibrotic lung disease • Pulmonary fibrosis • Obstructive lung disease • Tuberculosis Mulloy, K et. al. Environmental Health Perspectives 2001;305-309
Malignant lung processes • Carcinogens suspected or known to cause lung cancer • Arsenic, silica dust, diesel exhaust, radon
Radon • Radon exposure poses one of the greatest risk for developing lung cancer among the other exposures listed previously • Clear odorless gas • Produced from breakdown of uranium • Causes production of radon daughters which emit alpha particles • Exposure to alpha particles cause mutations in DNA www.lungusa.org
Radon • Exposure to radon measured in working level months (WLM) • A working level is 130,000 MeV of potential alpha energy that is released from an amount of radon decay product in one liter of air • 1 working level month is one working level exposure for a period of 170 hours (average number of hours a miner would work) www.ma.utexas.edu
WLM • In an average home • Annual WLM is 0.2 • Lifetime exposure 10-20 WLM • In one study of Colorado Plateau underground uranium miners working before 1974 • WLM ranged between 465 to 16,467 Mulloy, K et. al. Environmental Health Perspectives 2001;305-309
Lung cancer attributed to radon exposure in uranium mining • Estimated that ~ 70% of all lung cancer deaths in nonsmoking miners are due to exposure to radon daughters • Approximately 40% of all lung cancer deaths in smoking miners are due to exposure to radon daughters Lubin JH, et al. J Natl Cancer Inst 1995 87:817-27.
Mechanism of action of damage to lung • Radon daughters are inhaled with mine dust • Alpha particles that pass through cell nuclei induce damage to DNA • Radiation damages cell membranes and blood vessels • Alpha particles cause water molecules to dissociate into free radicals which interact with biological molecules • Radiation causes a disruption in collagen metabolism Archer V, et al. JOEM 1998;40:460-74.
Compensation • Radiation Exposure Compensation Program (RECA) • Enacted in 1990 • Purpose: to provide compensation for people who developed particular cancers or diseases related to exposure to radiation from either working in the uranium mining industry or exposed via above ground nuclear weapon testing
Compensation for miners • Must have worked for at least one year or been exposed to 40 or more working level months (WLMs) of radiation in above or underground uranium mines in Arizona, Colorado, New Mexico, Wyoming, South Dakota, Washington, Idaho, North Dakota, Oregon, Texas, or Utah between 1942 and 1971. • AND • Must have developed at least one of these diseases • Primary cancer of the lung, trachea or bronchus • One of the following nonmalignant respiratory diseases • Pulmonary fibrosis or fibrosis of the lung • Cor pulmonale related to fibrosis of the lung • Silicosis • Pneumoconiosis • Payment amount: $100,000 www.bu.edu/formerworker
Compensation for millers • 1) Must have worked for at least one year in a uranium mill or transporting uranium ore or vanadium-uranium ore from mines or mills located in Arizona, Colorado, New Mexico, Wyoming, South Dakota, Washington, Idaho, North Dakota, Oregon, Texas, or Utah between 1942 and 1971. • AND • Must have developed at least one of these diseases • Primary cancer of the lung, trachea or bronchus • Renal cancer or other chronic renal diseases, including nephritis and kidney tubal tissue injury • One of the following nonmalignant respiratory diseases • Pulmonary fibrosis or fibrosis of the lung • Cor pulmonale related to fibrosis of the lung • Silicosis • Pneumoconiosis • Payment amount: $100,000 www.bu.edu/formerworker
RESEP • The Radiation Exposure Screening and Education Program • sponsored by the U.S. Department of Health and Human Services Division of Primary Health Care • Came about as a result of the RECA amendment of 2002 • “it should be the responsibility of Federal Government in partnership with State and local governments and appropriate healthcare organizations, to initiate and support programs designed for the early detection, prevention and education on radiogenic diseases” http://books.nap.edu
RESEP screening services • Health screening • History, physical exam, obtaining appropriate medical tests • Education • Detection and prevention of disease linked to exposure to radiation • Referral • for treatment • RECA counseling • Help with compensation claims
RESEP Screening protocols • History • must include date of exposure, place, duration of employment and tobacco use • Physical exam • emphasis on pulmonary, cardiac and renal exam • Chest radiography • standard posterior-anterior view chest radiograph for presence of radiologic fibrosis, silicosis or pneumoconiosis • Pulmonary Function testing • as needed including spirometry, lung volumes, arterial blood gases and a DLCO
Eligible for compensation • Nonmalignant disease • Biopsy or chest imaging documentation • Chest x-rays are interpreted by two readers • spirometry • FEV1 < 80% or FVC < 80% • ABG • pCO2 30 mmHG and pO2 < 70 for an altitude of > 3,000 feet or pO2 < 75 for an altitude < 3,000 feet • Malignant disease • Written documentation Mulloy, K. Environmental Health Perspectives 2001;109:305-9
Case • CXR s/p CABG, slight cardiomegaly, pulmonary vasculature normal, no infiltrate or pleural effusion, degenerative changes in the spine • ABG 7.42/34/51/-1.6/21.7/85.4% with FI02 of 21% • PFTs • FVC 3.72 Liters (54%) • FEV1 2.89 Liters (61%) • FEV1/FVC 0.78 (113%) • FEF 25% 6.50 (91%) • FEF 75% 1.02 L (100%) • FEF 25-75% 2.77 (86%) • FEF max 7.07 89% • Hgb 15.7 g/dL
RESEP screening protocol • If an abnormality is noted with the initial screening then further testing is waranted. • Includes high-resolution CT scans, bronchoscopy, V/Q scans, pulmonary angiography and thoracentesis, pleural bx, MRI and PET scanning, 24 hour urine testing, renal ultrasound, tissue biopsy or aspiration, endoscopy
RESEP follow up • Follow up for nonmalignant cases includes periodic re-evaluation • Follow up for malignant cases includes involving a case manager to help facilitate the process of documentation and follow up
Compensation • Amount of compensation $100,000 • Difficulties encountered with compensation claims • Often times it is difficult to document exposure to radon • Access to diagnostic resources can be difficult • Difficult to recognize the diseases Mulloy, K. Environmental Health Perspectives 2001;109:305-9
Prevention • Clean Air Act • Maximum uranium dose is 10 millirem from the air • Sets standards for site clean-up • A person’s risk for developing cancer must not be increased to greater than 1 in 10,000 • Safe Drinking Water Act • Limits contamination of water from uranium to no more than 30 micrograms per liter of water • Uranium Mill Tailings Radiation Act • Directs the EPA to set standards for clean up and disposal of contaminants • Limits air emissions and soil and groundwater contamination www.epa.gov
References • Assessment of the scientific information for the radiation exposure and screening and education program 2005. Accessed on 12/16/07 at http://books.nap.edu/openbook.php?record_id=11279&page=10 • Archer V, Renzetti A, Doggett R, et al. Chronic diffuse interstitial fibrosis of the lung in uranium miners. JOEM 1998;40:460-74. • Brugge D, Goble R. The history of uranium mining and the Navajo people. Am J Public Health 2002;92:1410-1419. • Gilliland F, Hunt WC, Pardilla M, et. al. Uranium mining and lung cancer experience among Navajo men in Arizona and New Mexico, 1969 to 1993. J Occup Environ Med 2000;42:278-83 • Lubin JH, Boice JD, Edling C, et al. Lung cancer in radon-exposed miners and the estimate of risk from indoor exposure. J Natl Cancer Inst 1995 87:817-27. • Mulloy K, James D, Mohs K, et. al. Lung cancer in a nonsmoking underground uranium miner. Environmental Health Perspectives 2001;305-309 • Radiation exposure compensation program. June 2006, accessed on 12/16/07 at http://www.bu.edu/formerworker/RECP_Factsheet.pdf • Uranium. Human Health Factsheet. August 2005, accessed on 12/15/07 at http://www.ead.anl.gov/pub/doc/Uranium.pdf • World Uranium Mining Nuclear Issues Briefing Paper 41 accessed on 12/15/07 at http://www.uic.com.au/nip41.htm