COBALT, RADIOACTIVE: Nuclear Power Plant Emissions
General Manufacturing Information :
Corrosion product radionuclides are created by neutron activation of reactor components such as piping or fuel element cladding. ... In addition, corrosion products can be found in workers who have had intakes at other nuclear facilities, notably nuclear power plants or naval shipyards servicing nuclear-powered vessels. ... Historically, fresh corrosion product radionuclides, regardless of origin, were usually a mixture of several radionuclides. The predominant radionuclide was usually cobalt-60, with cobalt-58, manganese-54, and iron-59 as the other significant constituents in a fresh mixture. Other radionuclides were often present in trace amounts, but they were generally of little dosimetric consequence. The relative abundance of the radionuclides varied from facility to facility. However, given the time elapsed since operation of the reactors at Hanford, the short-lived corrosion products have decayed away, leaving cobalt-60 as the nuclide of concern. ...Corrosion products are usually oxides. /Cobalt, manganese, and iron oxides/
[Pacific Northwest National Laboratory; HANFORD: Radiation and Health Technology Methods and Models of the Hanford Internal Dosimetry Program. p. 11-1, PNNL-MA-860 (2003) Available at pnl.gov as of October 4, 2006 ]**PEER REVIEWED**
Environmental Fate/Exposure Summary :
Cobalt-60 is produced by neutron activation of components of nuclear reactors; these components are made of various alloys of steel that contain metals that can absorb neutrons and produce cobalt-60. Cobalt-60 can also be produced in a particle accelerator. Trace amounts of cobalt-60 are present in the environment worldwide due to fallout from past atmospheric nuclear weapons testing. Cobalt-60 may be released to the environment from nuclear reactors and facilities that process spent nuclear fuel, especially hardware associated with the spent fuel. Cobalt-60 may be release to the environment through discharges of low-level aqueous radioactive wastes from nuclear power plants. The highest annual discharge of cobalt-60 from the AEA Witfrith reactor in Dorset, UK was 20 TBq in 1980-81. Between 1986-90 approximately 270 GBq of cobalt-60 was discharged into the Rhone River in liquid wastes. Total releases of cobalt-60 to the atmosphere from the Savannah River Site (SRS), South Carolina between 1968-96 were 0.092 Ci. Total releases of cobalt-60 to streams from the SRS between 1954-95 were 66 Ci. Occupational exposure to cobalt-60 may occur for workers at nuclear facilities, irradiation facilities, and nuclear waste storage sites. Cobalt-60 is used in brachytherapy to treat various types of cancer. In this application, cobalt-60 is contained within a sealed source, and the release of cobalt-60 to the environment would be expected to be minimal and exposure to cobalt-60 by cancer patients would be limited to its gamma emission rather than to the element itself. Individuals may be exposed to cobalt-57 through its use in diagnostic testing as a radiotracer in radioactive vitamin B12. According to the US Nuclear Regulatory Commission, the collective intake of cobalt-60 by ingestion and inhalation at power reactors in 1998 was 352 uCi for 25 intake records and 27,000 uCi for 281 intake records, respectively. The collective intake at fuel fabrication facilities was 0.486 uCi for 502 intake records. (SRC)
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Artificial Pollution Sources :
Cobalt-60 is produced be neutron activation of components of nuclear reactors; these components are made of various alloys of steel that contain metals that can absorb neutrons and produce cobalt-60(1). Cobalt-60 can also be produced in a particle accelerator(1). Trace amounts of cobalt-60 are present in the environment worldwide due to fallout from past atmospheric nuclear weapons testing(1). Cobalt-60 may be released to the environment from nuclear reactors and facilities that process spent nuclear fuel, especially hardware associated with the spent fuel(1). Cobalt-60 may be release to the environment through discharges of low-level aqueous radioactive wastes from nuclear power plants(5). The highest annual discharge of cobalt-60 from the AEA Witfrith reactor in Dorset, UK was 20 TBq in 1980-81(2). Between 1986-90 approximately 270 GBq of cobalt-60 was discharged into the Rhone River in liquid wastes(3). Total releases of cobalt-60 to the atmosphere from the Savannah River Site (SRS), South Carolina between 1968 and 1996 were 0.092 Ci(4). Total releases of cobalt-60 to streams from the SRS between 1954-95 were 66 Ci(4). Cobalt-60 is used in brachytherapy to treat various types of cancer(1). In this application, cobalt-60 is contained within a sealed source, and the release of cobalt-60 to the environment would be expected to be minimal(SRC).
[(1) Argonne National Laboratory/EVS. Human Health Fact Sheet, August 2005. Cobalt. Available at: ead.anl.gov as of Nov 3, 2005. (2) Cundy AB et al; Environ Sci Technol 33: 2841-49 (1999) (3) Beaugelin-Seiller K et al; J Environ Radioact 24: 217-23 (1994) (4) DOE; Assessment of radionuclides in the Savannah River Site. Environmental summary DE-AC09-96SR18500 . WSRC-TR-98-00162 (1998) (5) ATSDR; Toxicological Profile for Cobalt. April 2004. Dept Hlth Human Service, Public Hlth Service, Agency for Toxic Substances and Disease Registry pp. 207-264 (2004) ]**PEER REVIEWED**
Human Toxicity Excerpts :
/OTHER TOXICITY INFORMATION/ Workers in commercial nuclear power plants are typically exposed to gamma radiation. The main routes of exposures are from fission products and activation products. The activation product of greatest concern is cobalt-60, which emits energetic gamma-rays of 1.15 and 1.33 MeV per nuclear transformation. The average annual effective dose of monitored workers in the commercial fuel cycle between 1985 and 1989 was 2.9 mSv and the annual average collective dose was 2,500 person-Sv. /Cobalt-60/
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V75 70 (2001)]**PEER REVIEWED**
Effluent Concentrations :
On July 1, 1992, 68 MBq of cobalt-60 was released form the nuclear power plant of Bugey located on the Rhone River, France; two of the reactors are cooled using water from the Rhone River(1). Between 1986-90 approximately 270 GBq of cobalt-60 was discharged into the Rhone River in liquid wastes(1). The highest annual discharge of cobalt-60 from the AEA Winfrith reactor in Dorset, UK was 20 TBq in 1980-81(2). Concentrations of cobalt-60 in the intertidal mudflat sediments, seaweed, and marine fauna declined following the closure of the nuclear reactor at AEA Winfrith in Dorset, UK in 1990(2).
[(1) Beaugelin-Seiller K et al; J Environ Radioact 24: 217-23 (1994) (2) Cundy AB et al; Environ Sci Technol 33: 2841-49 (1999) ]**PEER REVIEWED**
Disposal Methods :
Low-level radioactive waste (LLW) is a general term for a wide range of wastes. Industries, hospitals and medical, educational, or research institutions; private or government laboratories; and nuclear fuel cycle facilities (e.g., nuclear power reactors and fuel fabrication plants) using radioactive materials generate low-level wastes as part of their normal operations. These wastes are generated in many physical and chemical forms and levels of contamination.
[Health Physics Society, Radiation Terms and Definitions: Low-level Radioactive Waste (2005). Available from hps.org as of November 28, 2005. ]**PEER REVIEWED**
Sediment/Soil Concentrations :
SEDIMENT: Cobalt-60 concentration in surface sediments from 4 sites in one of the reservoir created in the river Techna near the Mayak Production Association in the Urals mountains, which produced weapons-grade plutonium, ranged from 42 to 88 kBq/kg dry weight(1). Cobalt-60 concentrations in bottom sediments collected near the Vandellos Nuclear Plant (Spain) in 1989 ranged from <0.07 to 0.44 Bq/kg(2). Cobalt-60 concentrations in sediment samples from the Peconic River system, Long Island, NY, downstream from the Brookhaven National Laboratory (BNL) were 9.6, 6.7, 9.6, and 10.5 Bq/kg dry weight at depth intervals of 0.00 to 0.06, 0.06 to 0.15, 0.15 to 0.24, and 0.24 to 0.37 meters, respectively(3). On the BNL property boundary, cobalt-60 concentrations in sediment were 5.8 Bq/kg dry weight (0.00-0.06 m) and <4 Bq/kg dry weight for the remaining depth intervals(3). Cobalt-60 concentrations in sediment samples from two locations from a control river, Connetquot River (Long Island, NY), were <4 Bq/kg at 0.00 to 0.06 and 0.06 to 0.15 m depths(3).
[(1) Standring WJF et al; Environ Sci Technol 36: 2330-7 (2002) (2) Sanchez-Cabeza JA, Molero J; J Environ Radioact 51: 211-28 (2000) (3) Rapiejko A et al; Health Phys 81: 698-703 (2001) ]**PEER REVIEWED**
Plant Concentrations :
Cobalt-60 concentrations in sea grass (Possidonia oceanica) collected near the Vandellos Nuclear Plant (Spain) collected in 1987 ranged from 0.70 to 7.66 Bq/kg dry weight, with a mean value of 1.6 Bq/kg dry weight(2).
[(1) Sanchez-Cabeza JA, Molero J; J Environ Radioact 51: 211-28 (2000) ]**PEER REVIEWED**
Probable Routes of Human Exposure :
Occupational exposure to cobalt-60 may occur for workers at nuclear facilities, irradiation facilities, and nuclear waste storage sites(1). According to the US Nuclear Regulatory Commission, the collective intake of cobalt-60 by ingestion and inhalation at power reactors in 1998 was 352 uCi for 25 intake records and 27,000 uCi for 281 intake records, respectively(1). The collective intake at fuel fabrication facilities was 0.486 uCi for 502 intake records(1). Cobalt-60 is used in brachytherapy to treat various types of cancer(2). In this application, cobalt-60 is contained within a sealed source(2). Individuals may be exposed to cobalt-57(SRC) through its use in diagnostic testing as a radiotracer in radioactive vitamin B12(3).
[(1) ATSDR; Toxicological Profile for Cobalt. April 2004. Dept Hlth Human Service, Public Hlth Service, Agency for Toxic Substances and Disease Registry pp. 207-264 (2004) (2) Argonne National Laboratory/EVS. Human Health Fact Sheet, August 2005. Cobalt. Available at: ead.anl.gov as of Nov 3, 2005. (3) O'Neil MJ, ed; The Merck Index. 13th ed., Whitehouse Station, NJ: Merck and Co., Inc., p. MISC-43 (2001) ]**PEER REVIEWED**
General Manufacturing Information :
Cobalt-59 is the only naturally occurring isotope of the element. The other twenty-two isotopes and their metastable states, ranging from mass numbers 50 to 67, are radioactive. Isotopes with mass numbers less than 59 decay by positron emission or electron capture. Isotopes with mass numbers greater than 59 decay by beta and gamma emission. Except for cobalt-60, the most important radionuclide, their half-lives range from milliseconds to days. The principal isotopes of cobalt (with their half-lives) are cobalt-57 (t 1/2 272 days), cobalt-58 (t 1/2 71 days), and cobalt-60 (t 1/2 5.27 years). Isotopes 57 and 58 can be determined by X-ray as well as gamma spectrometry. Isotope 60 is easily determined by gamma spectrometry. /Cobalt isotopes/
[Multi-Agency Radiological Laboratory Analytical Protocols Manual Volume II: Chapters 10-17 and Appendix F. (July 2004) p 14-120 NUREG-1576, EPA 402-B-04-001B, NTIS PB2004-105421. Available at nrc.gov as of October 12, 2006 ]**PEER REVIEWED**
Other Chemical/Physical Properties :
DECAY PATHWAY: Cobalt-60, half-life 5.27 years, decays via beta(-) emission (99.9%, 317.9 keV maximum, 95.8 keV average energy) and gamma emission (abs intensities: 99% 1173 keV; 100% 1332 keV) to nickel-60, half-life stable
[Korea Atomic Energy Research Institute. Nuclear Data Evaluation Lab. 2000. Nuclide Table. Available from the database query page at atom.kaeri.re.kr as of Nov 18, 2005. ]**PEER REVIEWED**
Radiation Limits & Potential :
DECAY PATHWAY: Cobalt-60, half-life 5.27 years, decays via beta(-) emission (99.9%, 317.9 keV maximum, 95.8 keV average energy) and gamma emission (abs intensities: 99% 1173 keV; 100% 1332 keV) to nickel-60, half-life stable
[Korea Atomic Energy Research Institute. Nuclear Data Evaluation Lab. 2000. Nuclide Table. Available from the database query page at atom.kaeri.re.kr as of Nov 18, 2005. ]**PEER REVIEWED**
Interactions :
Vitexina, a product containing the flavonoid vitexin as the main component, is derived from a plant, Vigna radiata (L.), that has been traditionally used in Vietnam for detoxification. This remedy is also used to treat the symptoms of conditions classified as "hot" in traditional medicine. The present study is a randomized, placebo-controlled comparative clinical trial for investigating the radioprotective effects of Vitexina for breast cancer patients undergoing radiotherapy with cobalt-60. No relevant weight loss, (even weight gain), occurred in 70% of patients in the Vitexina group, whereas 73% of the placebo group lost 1 to 2 kg of weight after 6 weeks of radiation therapy. The administration of Vitexina produced a significantly protective effect in peripheral blood cells in amount and in lymphocyte blast-transformation function. Condition of hot was observed in almost all cancer patients in this study by tongue examination. Hot condition did not change in the Vitexina group, but the incidence of hot and extreme hot cases were significantly increased in the placebo group after 6 weeks of radiation therapy. The results suggest that application of medicinal plants of the "clearing heat and detoxification" classification as an adjuvant would be a potential solution in integrative cancer therapy. /Vitexina and Cobalt-60/
[Hien TV et al; Integr Cancer Ther 1 (1): 38-4 (2002) ]**PEER REVIEWED** PubMed Abstract
Other Chemical/Physical Properties :
Half-life: 271.8 days, gamma emission /Cobalt-57/
[Lide, D.R. CRC Handbook of Chemistry and Physics 86TH Edition 2005-2006. CRC Press, Taylor & Francis, Boca Raton, FL 2005, p. 11-64]**PEER REVIEWED**
Storage Conditions :
The half-life of cobalt-60 (t1/2= 5.2 y), and its gamma emissions make it a principal contributor to potential dose effects in storage and transport of radioactive waste. /Cobalt-60/
[Multi-Agency Radiological Laboratory Analytical Protocols Manual Volume II: Chapters 10-17 and Appendix F. (July 2004) p 14-120 NUREG-1576, EPA 402-B-04-001B, NTIS PB2004-105421. Available at nrc.gov as of October 12, 2006 ]**PEER REVIEWED**
Radiation Limits & Potential :
Half-life: 271.8 days, gamma emission /Cobalt-57/
[Lide, D.R. CRC Handbook of Chemistry and Physics 86TH Edition 2005-2006. CRC Press, Taylor & Francis, Boca Raton, FL 2005, p. 11-64]**PEER REVIEWED**
Other Chemical/Physical Properties :
In aqueous solution and in the absence of complexing agents, Co+2 is the only stable oxidation state, existing in water as the pink-red hexaaquo complex ion, Co(H2O)6 +2. Simple cobalt ions in the +3 oxidation state decompose water in an oxidization-reduction process that generates Co+2. ... Complexation of Co+3 decreases its oxidizing power and most complex ions of the +3 oxidation state are stable in solution. ... Chelate complexes are well-known and are used to extract cobalt from solutions of other ions. /Cobalt compounds/
[Multi-Agency Radiological Laboratory Analytical Protocols Manual Volume II: Chapters 10-17 and Appendix F. (July 2004) p 14-121 NUREG-1576, EPA 402-B-04-001B, NTIS PB2004-105421. Available at nrc.gov as of October 12, 2006 ]**PEER REVIEWED**
Therapeutic Uses :
Teletherapy is radiation therapy delivered using an external beam of ionizing radiation. Options include gamma rays (from a radioactive cobalt-60 source) and photons or electrons (from an X-ray generator or accelerator). ... Electrons, which have less power to penetrate tissue, are used to treat skin lesions, superficial lymph nodes, and other tumors situated near the surface of the patient. In addition to "conventional" radiation therapy, experts in radiation oncology have developed several other methods of external beam therapy. Intraoperative radiation therapy (IORT) uses electrons to treat tumors that have been surgically exposed. IORT delivers a single high dose of radiation directly to the tumor after overlying and surrounding tissue have been temporarily moved out the way. IORT is of greatest use for accessible tumors of the abdomen and pelvis that cannot be removed surgically. Stereotactic radiosurgery (SRS) delivers radiation beams to a small target within the skull. The resulting dose distribution yields a small region of high dose precisely conforming to the target. ... /Cobalt-60/
[ Radiation in Medicine: A Need for Regulatory Reform (1996) Institute of Medicine (IOM), National Academies of Science ]**PEER REVIEWED**
Major Uses :
Cobalt is also used in the cobalt bomb, a hydrogen bomb surrounded by a cobalt metal shell. When the nuclear explosion occurs cobalt-60 is formed from cobalt-59 by neutron capture. Considered a dirty bomb because of long half-life and intense beta and gamma radiation.
[O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 426]**PEER REVIEWED**
Major Uses :
Cobalt-57. Used in nuclear medicine to help physicians interpret diagnostic scans of patients' organs, and to diagnose pernicious anemia.
[Medical and Industrial Uses of Radioactive Materials, NEI Nuclear Energy Institute, Washington, DC, April 2003 www.nei.org as of May 19, 2004 ]**PEER REVIEWED**
Disposal Methods :
Nuclear Regulatory Commission regulations separate low-level waste into three classes: A, B and C. The classification of the waste depends on the concentration, half-life and types of the various radionuclides it contains. The NRC sets requirements for packaging and disposal of each class of waste. Class A low-level waste contains radionuclides with the lowest concentrations and the shortest half-lives. About 95 percent of all low-level waste is categorized as Class A.
[Nuclear Energy Institute: Disposal of Low level Radioactive Wastes Fact Sheet, NEI. Available from nei.org as of November 28, 2005. ]**PEER REVIEWED**
Disposal Methods :
Low-level waste disposal occurs at commercially operated low-level waste disposal facilities that must be licensed by either the Nuclear Regulatory Commission or Agreement States. ... There are three existing low-level waste disposal facilities in the United States /Barnwell, SC, Richland, WA, Envirocare in Utah/ that accept ... low-level waste. All are in Agreement States.
[Nuclear Regulatory Commission, Low-Level Waste Disposal, NRC. Available from nrc.gov as of November 28, 2005. ]**PEER REVIEWED**
Radiation Limits & Potential :
For activities conducted under licenses issued by the Nuclear Regulatory Commission, the monthly average concentration (uCi/mL) for releases to sewers for Class W cobalt compounds is as follows: cobalt-55 2x10-4; cobalt-56 6x10-5, cobalt-57 6x10-4, cobalt-58 2x10-4, cobalt-60 3x10-5.
[10 CFR 20; Department of Energy, Nuclear Regulatory Commmission Standards for Protection Against Radiation p. 321-424 (2003) ]**PEER REVIEWED**
Radiation Limits & Potential :
The Orphan Sources Initiative is designed to assist states in retrieving and disposing of radioactive sources that find their way into non-nuclear facilities, particularly scrap yards, steel mills, and municipal waste disposal facilities. Specially licensed sources bear identifying markings that can be used to trace these sources to their original owners. However, some sources do not have these markings or the markings become obliterated. In these cases, the sources are referred to as orphan sources because no known owner can be identified. They are one of the most frequently reported radioactive contaminants in shipments received by scrap metal facilities. If a steel mill melts a source, it contaminates the entire batch of metal, the processing equipment, and the facility. More importantly, it can result in the exposure of workers to radiation. There have been at least 26 recorded accidental meltings of radioactive material in the United States since 1983. One such case happened in Texas in 1996 when a cobalt-60 source was stolen from a storage facility and sold as scrap metal. Workers and customers of the scrap yard and law enforcement officers who conducted investigations at the scrap yard were exposed to the source and may have received dangerous doses of radiation. /Cobalt-60/
[EPA, Office of Air and Radiation; Orphan Sources Initiative. Last updated: January 21, 2003. Available from: epa.gov as of August 22, 2003. ]**PEER REVIEWED**
Medical Surveillance :
/In nuclear reactor workers/ in vivo and excreta measurements are the bioassay methods used in monitoring for corrosion product radionuclides /predominently cobalt-60/. All of these radionuclides are gamma-emitters and can be measured directly using in vivo techniques. Whole body counting, using either sodium-iodide or coaxial germanium detectors, is the in vivo technique typically applied for bioassay of these nuclides. Because the radionuclides are easily detectable using in vivo measurement, excreta measurements are not required in most intake situations, unless there is concern for other radionuclides such as strontium or plutonium, which are not readily measurable by in vivo techniques. Measurement of radionuclides in early fecal excretion can be used as a means for establishing the relative radionuclide distribution in a corrosion product mixture; however, analysis of a nasal or appropriate surface contamination smear sample is preferred if the elements present may exhibit different absorption characteristics in the GI tract.
[Pacific Northwest National Laboratory; HANFORD: Radiation and Health Technology Methods and Models of the Hanford Internal Dosimetry Program. p. 11-8, PNNL-MA-860 (2003) Available at pnl.gov as of October 4, 2006 ]**PEER REVIEWED**
Mechanism of Action :
Apoptosis is a crucial phenomenon for radiation-induced cell death. Since Bax plays a critical role in inducing apoptosis via p53-dependent and -independent pathways, /the authors/ analyzed a role of Bax in radiation sensitivity in esophageal carcinoma cells. Using eight human esophageal carcinoma cell lines, irradiation was performed with cobalt-60 gamma-rays. Radiation sensitivity was determined by induction of apoptosis, which was assessed by morphological change in nuclear condensation of chromatin, DNA ladder formation and apoptosis-related genes after irradiation. The survival curve was evaluated by clonogenic assay using a parameter D0 after irradiation, compared to that of the control. After transfection of the bax gene into low radiation sensitivity, TE-1 cells were conducted by lipofection method using pSFFV-Neo vector carrying bax cDNA. Radiation sensitivity of esophageal carcinoma cells was associated with induction of apoptosis, in a time- and dose-dependent manner. Induction of apoptosis affects early responsiveness to irradiation rather than the parameter D0. Radiation-induced apoptosis was associated with an increase in expression of bax gene, regardless of p53 genetic status. The introduction of the bax gene into a low radiation sensitivity cell line, TE-1, enhanced radiation sensitivity in association with increased apoptotic cell death after irradiation. Radiation sensitivity of esophageal carcinoma cells can be evaluated by induction of apoptosis, as an early predictive marker for radiation response. The proapoptotic gene bax plays a critical role in the determination of tumor response in radiation therapy. /Cobalt-60/
[Kim R et al; Int J Mol Med 14 (4): 697-706 (2004) ]**PEER REVIEWED** PubMed Abstract
Threshold Limit Values :
The Physical Agents TLV Committee accepts the occupational exposure guidance of the International Commission on Radiological Protection (ICRP). Ionizing radiation includes particulate radiation (e.g., alpha particles and beta particles emitted from radioactive materials, and neutrons from nuclear reactors and accelerators) and electromagnetic radiation (e.g., gamma rays emitted from radioactive materials and x-rays from electron accelerators and X-ray machines) with energy greater than 12.4 electron-volts (eV) ... The guiding principle of radiation protection is to avoid all unnecessary exposures. ICRP has established principles of radiological protection. There are (1) the justification of a work practice: No work practice involving exposure to ionizing radiation should be adopted unless it produces sufficient benefit to the exposed individuals or the society to offset the detriment it causes. (2) The optimization of a workpractice: All radiation exposures must be kept as low as reasonably achievable (ALARA), economic and social factors being taken into account. (3) The individual dose limits: The radiation dose from all relevant sources should not exceed the /ICRP/ prescribed dose limits.
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2006, p. 140]**PEER REVIEWED**
Other Occupational Permissible Levels :
The recommendations in the American National Standards Institute standard, ANSI Z88.2-1992, "American National Standard For Respiratory Protection," are endorsed by the U.S. Nuclear Regulatory Commission and may be used by licensees in establishing a respiratory protection program with the /several/exceptions /including limitations that do not permit or greatly restrict the use of quarter-facepiece respirators and supplied air respirators and self-contained breathing apparatus (SCBA) that operate in the demand mode./
[U.S. Nuclear Regulatory Commission; Regulatory Guide 8.15 - Acceptable Programs for Respiratory Protection. October 1999. Available at nrc.gov as of October 2, 2006 ]**PEER REVIEWED**
FDA Requirements :
Based on its experience in regulating investigational radioactive pharmaceuticals, the Nuclear Regulatory Commission has compiled a list of reactor-produced isotopes for which it considers that applicants may reasonably be expected to submit adequate evidence of safety and effectiveness for use as recommended in appropriate labeling. Such use may include ... Isotope: cobalt 58 or cobalt 60; Chemical Form: labeled cyanocobalamin; Use: intestinal absorption studies.
[21 CFR 310.503(c); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from: gpoaccess.gov as of July 1, 2003 ]**PEER REVIEWED**
Special Reports :
U.S. Nuclear Regulatory Commission; Regulatory Guide 8.34 - Monitoring Criteria and Methods to Calculate Occupational Radiation Doses. 1992/ Available at nrc.gov as of September 25, 2006
MORE ABOUT HEALTH EFFECTS
Evidence for Carcinogenicity:
Evaluation. There is sufficient evidence in humans for the carcinogenicity of X-radiation and gamma-radiation. There is sufficient evidence in experimental animals for the carcinogenicity of X-radiation and gamma-radiation. Overall evaluation. X-radiation and gamma-radiation are carcinogenic to humans (Group 1).
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V75 304 (2000)]**PEER REVIEWED**
Human Toxicity Excerpts:
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ The accident occurred in Northern Italy ... .The source was cobalt-60. The operator entered the room and was not wearing a film badge. Of particular note was the rapid drop in white blood cells and lymphocytes and the onset of nausea and vomiting in less than 30 min. ... After an initial fever, the patient experienced a latent period for approximately 6 days, after which time fever rapidly rose and the patient died 12 days postexposure. The terminal event was listed as dramatic deregulation of the cardiac rhythm with extreme tachycardia, very high central temperature oscillations, and a Cheyne-Stokes rhythm. /Cobalt-60/
[Gusev, I.A., Guskova, A.K., Mettler, F.A. (eds) Medical Management of Radiation Accidents. Second Edition. CRC Press. Boca Raton, FL. 2001, p. 214]**PEER REVIEWED**
/CASE REPORTS/ Electron spin resonance and fluorescence in situ hybridization were used to evaluate the dose to the finger of a worker who accidentally touched a radiotherapy cobalt-60 therapy source in November 1995. In September 1999, the middle finger was amputated. /The authors/ estimated the dose to the bone of the finger to be 6.4+/-0.5 Gy using the electron spin resonance additive dose method and a corrected dose of about 20+/-3 Gy could be inferred by translocation analysis in peripheral lymphocytes using the fluorescence in situ hybridization method. This retrospective dosimetry was performed for the victim 4 years after the accident, but the compatibility of the results obtained by physical and biological methods reinforce their validity, although in the case of partial-body exposure the biological method has limitations and demonstrates the need to find appropriate correction factors. /Cobalt-60/
[Kinoshita A et al; Health Phys 84 (4): 477-82 (2003) ]**PEER REVIEWED** PubMed Abstract
/CASE REPORTS/ /EYE/ Exposure of a male worker to a whole-body dose of 159 rad (1.59 Gy) of cobalt-60 radiation resulted in a progressive deterioration of visual acuity, due to cataract development, in the left eye (which was more exposed than the right) over time. /Cobalt-60/
[DHHS/ATSDR; Toxicological Profile for Cobalt p. 112 (2004) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ A fatal radiation accident with a 2.43pentaBq (65 kCi) cobalt-60 radiation source occurred in Norway in 1982. The patient was estimated to have received an inhomogeneous whole body dose of approximately 10-30 Gy and he died on day 13 after the accident. The clinical features in general were consistent with a hematological syndrome variant of the acute radiation syndrome (ARS). Gastrointestinal symptoms were modest compared with the estimated dose. More recent insights cast doubt about the classical descriptions and interpretation of ARS, which show many similarities to the multi-organ failure (MOF) of otherwise severely traumatized patients. This report discusses the features of ARS in this case in relation to commonly accepted features of MOF, based on clinical and autopsy data. /Cobalt-60/
[Reitan JB et al; BJR Suppl 27: 36-40 (2005) ]**PEER REVIEWED** PubMed Abstract
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ In 1963, six cases of acute radiation sickness resulting from an accidental non-uniform cobalt-60 gamma-ray irradiation of approximately 10 Ci were treated first in Hefei, Anhui province, and were then transferred to our hospital. The whole body average doses were estimated to be 2x10+2 cGy to approximately 8x10+3 cGy. Two of patients died of intestinal acute radiation sickness within 2 weeks. Autopsy findings revealed findings consistent with multi-organ failure. Four cases survived, and one of them recovered from septicaemic shock. Loss of hair, systemic infection, high fever and bleeding occurred in five cases. The essential therapeutic measures were strict isolation, preventive treatment with anti-infection drugs, fresh blood transfusion and sometimes infusion of formed blood elements. Among the survivors, two cases received homologous bone marrow transfusion. The general conditions of four cases followed-up for a period of 24-40 years are apparently good, with transparent lens, normal thyroid function and normal immunological reactions, except one patient who had a low serum immunoglobulin G level. Three cases showed subnormal adrenocortical activity and impairment of sex gland function. Patient A died from a car accident 24 years after the radiation accident. Patient C gave birth to a daughter and a son; the latter had severe mental retardation. Serial electroencephalographic changes occurred only in those cases who received high cranial doses. In all the cases, persistence of chromosome aberrations in peripheral lymphocytes was observed. Owing to local high doses, the remote regional effects led to amputation of one leg in patient D and to pathological fracture of the femur in patient A. /Cobalt-60/
[Genyao Y, Changlin Y; BJR Suppl 27: 55-61 (2005) ]**PEER REVIEWED** PubMed Abstract
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ On 25 June 1990 in Shanghai, two men (Shi, a 56-year-old male, and Wan, a 53-year-old male) were accidentally exposed to homogeneous high dose and high dose rate cobalt-60 irradiation (total activity 0.85 PBq, at the time of delivery from the manufacturing factory in June 1960) up to 12 Gy and 11 Gy, respectively. Both suffered from an extremely severe hematopoietic form of acute radiation sickness. Through energetic salvage and human leukocyte antigen (HLA) haploidentical bone marrow transplantation, their survival times were prolonged to 25 days and 90 days, respectively. In the case of Wan, the implanted bone marrow resided and engrafted completely, and hematopoiesis was restored. However, the patient died of interstitial pneumonia 90 days after exposure to radiation. The clinical course of multi-organ failure and the valuable experience obtained from the management of these patients is of great significance in directing the prevention of multi-organ failure and the treatment of such patients in the future. Pathological findings from these two autopsy cases are helpful in elucidating the underlying pathogenesis of clinical multi-organ failure, the cause of death and especially, the pathogenesis and morphogenesis of lung fibrosis. /Cobalt-60/
[Changlin Y, Genyao Y; BJR Suppl 27: 47-54 (2005) ]**PEER REVIEWED** PubMed Abstract
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ In Istanbul, Turkey in 1998, a 3 TBq cobalt-60 therapy source inside a shielded transport container was sold as scrap. The individuals who purchased the source were unaware of the radiation hazard and proceeded to break open and dismantle the container in a residential area of Istanbul. A total of 18 persons, including 7 children, were admitted to hospital. Five exhibited clinical effects of acute radiation exposure, with one person having signs of radiation-induced skin injuries on the fingers of one hand. /Cobalt-60/
[United Nations Scientific Committee on the Effects of Atomic Radiation; Sources and Effects of Ionizing Radiation V.1: Sources p. 549 (2000) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ /A 43 pentaBecquerel (PBq) cobalt-60 source/ remained in the farmer's home for 212 hr and in his pocket for 52 hr. The source was also kept in the left pocket of his 7 year old brother's trousers for 18 hr. The average whole-body dose to the farmer and his younger brother was estimated to be 806 and 40 Gy. Both died on January 23 and 25, respectively, due to failure to respond to any medical treatment. Four other people, who received doses of 8, 6, 4, 2 Gy, respectively, survived after medical treatment. Two of them have not fully recovered from local injuries; the other two are doing well. A follow up study, together with involved medical treatment, has shown that in 17 years after exposure, they had fully recovered with good physical and mental condition and memory. Local effects are mainly long-term injuries to the skin and skeleton. There have been no significant changes in the lenses of their eyes. /Cobalt-60/
[Gusev, I.A., Guskova, A.K., Mettler, F.A. (eds) Medical Management of Radiation Accidents. Second Edition. CRC Press. Boca Raton, FL. 2001, p. 150]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ In Bangkok, Thailand in February 2000, three old radiotherapy heads /were/ taken to a scrap yard. One source, estimated to be about 15.5 TBq cobalt-60, was removed from its shielding. The resulting exposure caused 10 persons to be hospitalized, and three of these subsequently died. /Cobalt-60/
[United Nations Scientific Committee on the Effects of Atomic Radiation; Sources and Effects of Ionizing Radiation V.1: Sources p. 549 (2000) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ /A/ fatal accident in Israel involved an irradiator facility (12.6 PBq cobalt-60) used for sterilizing medical products and spices for the food industry. A distorted carton became jammed on the conveyor transport system while the source was in the exposed position. The operator disregarded the warning signal and entered the irradiation room. His whole-body dose was estimated to be about 10-15 Gy. Despite intensive medical care, he died of radiation effects 36 days after exposure. /Cobalt-60/
[United Nations Scientific Committee on the Effects of Atomic Radiation; Sources and Effects of Ionizing Radiation V.1: Sources p. 549 (2000) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ In /a/ fatal accident in Belarus, an operator was exposed to radiation in an industrial irradiator, following a jam in the product transport system, with the source (30 PBq cobalt-60) in the exposed position. A mean whole-body dose of approximately 11Gy, with localized areas of up to 18 Gy, was estimated. Despite intensive medical treatment, the operator died 113 days after exposure. /Cobalt-60/
[United Nations Scientific Committee on the Effects of Atomic Radiation; Sources and Effects of Ionizing Radiation V.1: Sources p. 549 (2000) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ /A/ fatal accident in China involved an irradiation facility (0.85 PBq cobalt-60) used for sterilizing traditional Chinese medicines. One of the two doors in the entry route had been out of commission. Seven workers entered to rearrange the product boxes/and/ two of the workers received doses of 11 and 12 Gy and subsequently died. /Cobalt-60/
[United Nations Scientific Committee on the Effects of Atomic Radiation; Sources and Effects of Ionizing Radiation V.1: Sources p. 549 (2000) ]**PEER REVIEWED**
/CASE REPORTS/ /ACUTE RADIATION SYNDROME/ ... /Seven workers were exposed to a 8.5X10+14 Bq cobalt-60 gamma source at a radiological medicine laboratory in Shanghai/. The seven workers suffered acute external radiation exposure of the whole body at widely varying degrees at different distances from the source in a short time. Within 30 min after the accident, one worker felt nauseated and within 7 hours, the other began vomiting. ... Dose reconstruction was made for the measurement and estimation of the radiation doses received by the seven workers, along with biological dose measurements. ... Chromosome aberration analysis and physical measurements agree within 10%. Two of the seven workers, who received 12 and 11 Gy radiation exposure, respectively, died after being treated for 25 and 90 days. The other five workers /who received between 2.0 and 5.2 Gy radiation exposure/ recovered after treatment. /Cobalt-60/
[Gusev, I.A., Guskova, A.K., Mettler, F.A. (eds) Medical Management of Radiation Accidents. Second Edition. CRC Press. Boca Raton, FL. 2001, p. 152]**PEER REVIEWED**
/EPIDEMIOLOGY STUDIES/ Following the observation of increased prostate cancer mortality related with cumulative external radiation dose in the UK Atomic Energy Authority... a nested case control study of prostate cancer risk among employees of the facility /was conducted/. The study showed that exposure to 5 radionuclides (tritium, chromium-51, iron-59, cobalt-60, zinc-65), evaluated separately, was associated with an increased risk of prostate cancer. Analyses of the association between external radiation dose and prostate cancer risk were carried out both for workers with probably exposure to the radionuclides and for those who had no such exposure. The association between external dose and prostate cancer was restricted to those with radionuclide exposure. /Tritium, chromium-51, iron-59, cobalt-60, zinc-65/
[NAS/BRER; Health Risks from Exposure to Low Levels of Ionizing Radiation BEIR VII-Phase 2. p. 355 (2005) ]**PEER REVIEWED**
/EPIDEMIOLOGY STUDIES/ Children who once resided in radiocontaminated apartments since early 1983 were examined for height and body weight status from age 1 month to 18 years and before they moved out of the apartments. The physical heights and body weights of 21,898 age- and sex-matched non-exposed children from a nationwide school surveillance in 1997-98 were taken as controls. The physical height data were shown as height percentiles (HP) compared with reference children and age-specific relative height differences (RHD). RESULTS: HP and RHD in 48 exposed boys and 37 girls were analysed using generalized estimating equations (GEE), which accounted for multiple measurements and correlation between these measurements in the same individuals during this period. After adjusting for effects from parental heights and body mass index (BMI), clear dose-related decreases in HP and RHD were observed in the exposed boys with a cumulative exposure > 60 mSv. CONCLUSIONS: Prolonged low dose-rate y-radiation exposure was associated with adverse effects on the physical heights of growing boys, but were less apparent in the exposed girls. /Low dose gamma radiation/
[Wang JC et al; Int J Radiat Biol 77 (1): 117-25 (2001) ]**PEER REVIEWED** PubMed Abstract
/BIOMONITORING/ /GENOTOXICITY/ Increased micronucleus frequency, both of single and multiple nucleates, /was found/ in 48 people who had been exposed to 0.12-16 Gy over a 2 to 10 year period as a result of a building contaminated with cobalt-60-containing steel. Subjects who lad left the building showed a decrease in micronucleus formation that correlated with time since cessation of exposure. /Cobalt-60/
[DHHS/ATSDR; Toxicological Profile for Cobalt p. 121 (2004) ]**PEER REVIEWED**
/BIOMONITORING/This ... has been performed with radiation victims who were accidentally exposed to a cobalt-60 source and its release into the environment. The aim of the study was to assess the effects of elevated radiation exposures on plasma level, on erythrocyte thiobarbituric acid reactive substance (TBARS) level and on erythrocyte glutathione (GSH) levels. Patients were treated in different hospitals with different symptoms such as nausea, vomiting, dizziness, along with severe anemia in some patients. Blood samples were collected 3 to 5 days following the radiation accident. Increases in plasma (6.25+/-0.90 nmol/mL)) and erythrocyte TBARS levels (330.5+/-30.5 umol/gHb)) were found in comparison to a healthy group (3.72+/-0.68 nmol/mL and 150.7+/-20.5 umol/gHb, respectively) at a significant level (p<0.001). Erythrocyte GSH levels (5.2+/-0.30 umol/gHb) were found to be decreased among the victims (healthy group: 10.2+/-0.7 umol/gHb) at the same significance level (p<0.001). These observations confirm a significant change induced by radiation in the oxidant/antioxidant status among the victims. It is suggested here that antioxidant supplementation therapy might be effective in preventing the harmful effects of cobalt-60 radiation among radiation victims. /Cobalt-60/
[Cemir M et al; J Environ Radioact 64(1):19-25 (2003) ]**PEER REVIEWED** PubMed Abstract
/BIOMONITORING/ Many people in Taiwan have been living in buildings constructed with cobalt-60-contaminated steel rods. To study the biological effects of chronic low-dose ionising radiation on the residents of one such building, micronucleus formation in these individuals was compared with that in controls. ... The 73 residents had 77 age-and-sex-matched controls: 31 had 31 close relatives as controls (group A controls); eight of the 31 had a second set of close relatives; and the other controls were 38 residents in neighboring buildings. Two micronucleus assays were used - a cytochalasin B (CBMN) assay and another involving incubation with cytarabine (CBMNA). Assay results are given as frequency, or the number of binucleate cells containing one micronucleus per 1000 randomly examined binucleate cells. Findings The CBMN and CBMNA mean (SD) frequencies for 31 exposed individuals (0.016 +/-0.009 and 0.025 +/-0.013 respectively) were greater than those for their group A controls (0.009 +/-0.004 and 0.016 +/-0.009, respectively) (p=0.0006 and 0.0002, respectively). The mean CBMN and CBMNA frequencies for all the exposed individuals (0.017+/-0.011 and 0.030 +/-0.014, respectively) were significantly greater than those for all controls (0.011+/-0.008 and 0.019+/-0.01; p=0?0001 for both comparisons). The ranges of the differences in CBMN or CBMNA frequencies between 31 exposed individuals and their group A controls were 0.003 to 0.020 and 0.001 to 0.032, respectively. After adjustment for age, sex, and cigarette smoking, the adjusted relative risks of micronucleus formation from radiation exposure in all 73 residents was 1.56 (95% CI 1.42-1.71; p=0?0001) by the CBMN assay and 1.64 (1.53-1.77; p=0?0001) by the CBMNA assay. ... These findings suggest that chronic low-dose and low-dose-rate gamma-ray environmental exposure may induce cytogenetic damage in human beings. /Cobalt-60/
[Chang WP et al; Lancet 350 (9074):330-3 (1009) ]**PEER REVIEWED**
/OTHER TOXICITY INFORMATION/ Workers in commercial nuclear power plants are typically exposed to gamma radiation. The main routes of exposures are from fission products and activation products. The activation product of greatest concern is cobalt-60, which emits energetic gamma-rays of 1.15 and 1.33 MeV per nuclear transformation. The average annual effective dose of monitored workers in the commercial fuel cycle between 1985 and 1989 was 2.9 mSv and the annual average collective dose was 2,500 person-Sv. /Cobalt-60/
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V75 70 (2001)]**PEER REVIEWED**
Medical Surveillance:
/In nuclear reactor workers/ in vivo and excreta measurements are the bioassay methods used in monitoring for corrosion product radionuclides /predominently cobalt-60/. All of these radionuclides are gamma-emitters and can be measured directly using in vivo techniques. Whole body counting, using either sodium-iodide or coaxial germanium detectors, is the in vivo technique typically applied for bioassay of these nuclides. Because the radionuclides are easily detectable using in vivo measurement, excreta measurements are not required in most intake situations, unless there is concern for other radionuclides such as strontium or plutonium, which are not readily measurable by in vivo techniques. Measurement of radionuclides in early fecal excretion can be used as a means for establishing the relative radionuclide distribution in a corrosion product mixture; however, analysis of a nasal or appropriate surface contamination smear sample is preferred if the elements present may exhibit different absorption characteristics in the GI tract.
[Pacific Northwest National Laboratory; HANFORD: Radiation and Health Technology Methods and Models of the Hanford Internal Dosimetry Program. p. 11-8, PNNL-MA-860 (2003) Available at pnl.gov as of October 4, 2006 ]**PEER REVIEWED**
Probable Routes of Human Exposure:
Occupational exposure to cobalt-60 may occur for workers at nuclear facilities, irradiation facilities, and nuclear waste storage sites(1). According to the US Nuclear Regulatory Commission, the collective intake of cobalt-60 by ingestion and inhalation at power reactors in 1998 was 352 uCi for 25 intake records and 27,000 uCi for 281 intake records, respectively(1). The collective intake at fuel fabrication facilities was 0.486 uCi for 502 intake records(1). Cobalt-60 is used in brachytherapy to treat various types of cancer(2). In this application, cobalt-60 is contained within a sealed source(2). Individuals may be exposed to cobalt-57(SRC) through its use in diagnostic testing as a radiotracer in radioactive vitamin B12(3).
[(1) ATSDR; Toxicological Profile for Cobalt. April 2004. Dept Hlth Human Service, Public Hlth Service, Agency for Toxic Substances and Disease Registry pp. 207-264 (2004) (2) Argonne National Laboratory/EVS. Human Health Fact Sheet, August 2005. Cobalt. Available at: ead.anl.gov as of Nov 3, 2005. (3) O'Neil MJ, ed; The Merck Index. 13th ed., Whitehouse Station, NJ: Merck and Co., Inc., p. MISC-43 (2001) ]**PEER REVIEWED**
Antidote and Emergency Treatment:
Immediate First Aid/ Ensure that adequate decontamination has been carried out as needed. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (Head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Radiological Threats: Radiological Dispersal Devices or Weapons/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 502]**PEER REVIEWED**
Basic Treatment. Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 mL/min. Monitor for shock and treat if necessary. Anticipate seizures and treat if necessary. Perform routine emergency care for associated injuries. ... Perform routine basic life support care as necessary. /Radioactives I, II, and III/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 166]**PEER REVIEWED**
Basic Treatment. Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for shock and treat if necessary. Anticipate seizures and treat if necessary. Perform routine emergency care for associated injuries. For eye contamination, flush eyes immediately with water. Irrigate each eye continuously during transport. Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a good gag reflex, and does not drool. Perform routine BLS care as necessary. /Radiological Threats: Radiological Dispersal Devices or Weapons/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 502]**PEER REVIEWED**
Advanced Treatment. Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or is in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias as necessary. Start IV administration of 0.9% saline (NS) or lactated Ringer's (LR) TKO. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload. Treat seizures with diazepam or lorazepam. Perform routine advanced life support care as needed. Use proparacaine hydrochloride to assist eye irrigation. /Radioactives I, II, and III/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 166]**PEER REVIEWED**
Advanced Treatment. Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or is in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias as necessary. Start IV administration of 0.9% saline (NS) or lactated Ringer's (LR). For hypotension with signs of hypovolemia, administered fluid cautiously. Watch for signs of fluid overload. Treat seizures with diazepam (Valium) or lorazepam (Ativan). Perform routine advanced life support care as needed. Use proparacaine hydrochloride to assist eye irrigation. /Radiological Threats: Radiological Dispersal Devices or Weapons/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 503]**PEER REVIEWED**
Special Considerations. Most symptoms from radioactive product exposure are delayed; treat other medical or trauma problems according to normal protocols. An accurate history of the exposure is essential to determine risk and proper treatment modalities. The dose of radiation determines the type and clinical course of exposure: 100 rads: GI symptoms (nausea, vomiting, abdominal cramps, diarrhea). Symptom onset within a few hours. 600 rads: Several GI symptoms (necrotic gastroenteritis) may result in dehydration and death within a few days. Several thousand rads: neurological/cardiovascular symptoms (confusion, lethargy, ataxia, seizures, coma, cardiovascular collapse) within minutes to hours. Bone marrow depression, leukopenia, and infections usually follow severe exposures./Radioactives I, II, and III/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 167]**PEER REVIEWED**
Special Considerations. Radiation monitors should be available to evaluate the radiation dose rates and compute/verify safe times to remain in contaminated areas. Experts are needed to review the data and provide specific recommendations to the Incident Commander as to the hazards present in the affected areas. Medical radiation experts should be available to guide patient treatment. Most symptoms from radioactive product exposure are delayed; treat other medical or trauma problems according to normal protocols. An accurate history of the exposure is essential to determine risk and proper treatment modalities. The dose of radiation determines the type and clinical course of exposure: 100 rads: GI symptoms (nausea, vomiting, abdominal cramps, diarrhea). Symptom onset within a few hours. 600 rads: Severe GI symptoms (Necrotic gastroenteritis) may result in dehydration and death within a few days. Several thousand rads: neurological/cardiovascular symptoms (confusion, lethargy, ataxia, seizures, coma, cardiovascular collapse) within minutes to hours. Bone marrow depression, leukopenia, and infections usually follow severe exposures. Assistance and advice on patient care concerns may be obtained from the Oak Ridge Radiation Emergency Assistance Center and Training Site 24 hours a day by calling (615) 576-3131 or (615) 481-1000, ext. 1502 or beeper 241. /Radiological Threats: Radiological Dispersal Devices or Weapons/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 503]**PEER REVIEWED**
Emergency and Supportive Measures. Treatment of serious medical problems takes precedence over radiologic concerns. Maintain an open airway and assist ventilation if necessary. Treat coma and seizures if they occur. Replace fluid losses from gastroenteritis with intravenous crystalloid solutions. Treat leukopenia and resulting infections as needed. Immunosuppressed patients require reverse isolation and appropriate broad-spectrum antibiotic therapy. Bone marrow stimulants may help selected patients. Specific drugs and antidotes. Chelating agents or pharmacologic blocking drugs may be useful in some cases of ingestion or inhalation of certain biologically active radioactive materials, if they are given before or shortly after exposure. /Radiation (Ionizing)/
[Olson, K.R. (Ed.); Poisoning & Drug Overdose. 4th ed. Lange Medical Books/McGraw-Hill. New York, N.Y. 2004., p. 329]**PEER REVIEWED**
Decontamination. 1. Exposure to particle-emitting solids or liquids. The victim is potentially highly contaminating to rescuers, transport vehicles, and attending health personnel. 1. Remove victims from exposure, and if their conditions permit, remove all contaminated clothing and wash the victims with soap and water. b. All clothing and cleansing water must be saved, evaluated for radioactivity, and properly disposed of. c. Rescuers should wear protective clothing and respiratory gear to avoid contamination. At the hospital, measures must be taken to prevent contamination of facilities and personnel. d. Induce vomiting or perform gastric lavage if radioactive material has been ingested. Administer activated charcoal, although its effectiveness is unknown. Certain other adsorbent materials may also be effective. e. Contact Radiation Emergency Assistance Center & Training Site (REAC/TS/: telephone (865) 576-3131 or (865) 481-1000)/ and the state radiologic health department for further advice. In some exposures, unusually aggressive steps may be needed (eg, lung lavage for significant inhalation of plutonium). 2. Electromagnetic radiation exposure. The patient is not radioactive and does not pose a contamination threat. There is no need for decontamination once the patient has been removed from the source of exposure, unless electromagnetic radiation emitter fragments are embedded in body tissues. /Radiation (Ionizing)/
[Olson, K.R. (Ed.); Poisoning & Drug Overdose. 4th ed. Lange Medical Books/McGraw-Hill. New York, N.Y. 2004., p. 330]**PEER REVIEWED**
Initial Emergency Department Considerations. Chelating agents or pharmacologic blocking drugs (potassium iodine, diethylenetriamine pentaacetic acid (DTPA), dimercaprol (British antilewisite, BAL), sodium bicarbonate, Prussian blue, calcium gluconate, ammonium chloride, barium sulfate, sodium alginate, D-penicillamine) may be useful if given before or immediately after exposure. The Oak Ridge number listed /in Special Considerations/ can be contacted for specific treatment advice. /Radiological Threats: Radiological Dispersal Devices or Weapons/ p
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 503]**PEER REVIEWED**
Basic Treatment. Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary. Monitor for shock and treat if necessary. FOr eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport. Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. administer activated charcoal. /Cobalt and Related Compounds/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 386]**PEER REVIEWED**
Advanced Treatment. Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema. Consider administering a beta agonist such as albuterol for severe bronchospasm. Monitor cardiac rhythm and treat arrhythmias if necessary. Start IV administration of D5W TKO. Use o.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluids cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload. Use proparacaine hydrochloride to assist eye irrigation. /Cobalt and Related Compounds/
[Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 386]**PEER REVIEWED**
Evidence for Carcinogenicity:
Evaluation. There is sufficient evidence in humans for the carcinogenicity of X-radiation and gamma-radiation. There is sufficient evidence in experimental animals for the carcinogenicity of X-radiation and gamma-radiation. Overall evaluation. X-radiation and gamma-radiation are carcinogenic to humans (Group 1).
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V75 304 (2000)]**PEER REVIEWED**
Probable Routes of Human Exposure:
Occupational exposure to cobalt-60 may occur for workers at nuclear facilities, irradiation facilities, and nuclear waste storage sites(1). According to the US Nuclear Regulatory Commission, the collective intake of cobalt-60 by ingestion and inhalation at power reactors in 1998 was 352 uCi for 25 intake records and 27,000 uCi for 281 intake records, respectively(1). The collective intake at fuel fabrication facilities was 0.486 uCi for 502 intake records(1). Cobalt-60 is used in brachytherapy to treat various types of cancer(2). In this application, cobalt-60 is contained within a sealed source(2). Individuals may be exposed to cobalt-57(SRC) through its use in diagnostic testing as a radiotracer in radioactive vitamin B12(3).
[(1) ATSDR; Toxicological Profile for Cobalt. April 2004. Dept Hlth Human Service, Public Hlth Service, Agency for Toxic Substances and Disease Registry pp. 207-264 (2004) (2) Argonne National Laboratory/EVS. Human Health Fact Sheet, August 2005. Cobalt. Available at: ead.anl.gov as of Nov 3, 2005. (3) O'Neil MJ, ed; The Merck Index. 13th ed., Whitehouse Station, NJ: Merck and Co., Inc., p. MISC-43 (2001) ]**PEER REVIEWED**
All of the above is directly from toxnet.nlm.nih.gov
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