Strategies for
Radioactive Decontamination of
Livestock
Thomas E. Johnson, PhD
Alexander Brandl, PhD
Department of Environmental
and Radiological Health Sciences
Colorado State University
tj@colostate.edu
970-491-0563
Overview
• Goal: Removal of radioactive materials from
surfaces of livestock— possibly from a dirty
bomb, nuclear weapon or reactor accident
Definitions
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Background radiation
Source Term
Contamination/Radiation
Radioactive Contamination: External
Internal Contamination
Fugitive dusts and re-suspension
Plume
Noble Gases
Fallout/Fission products
Background Radiation
• Radiation from the sun, cosmic rays, rocks,
soil, plants, water
• Usually naturally occurring
– Bulk is from the sun or when the earth was
formed
• Almost ALL radiation detection instruments
will read above zero when no “radioactive
material” is present
• Demonstration
Definitions
• Source term: Quantity of radioactive materials
that are available to be dispersed
• Radiation: emission of particles or energy
from an atom that may cause damage to the
body
• Contamination: unwanted radioactive
material in an unwanted place. Usually
particles
Definitions (2)
• Radioactive contamination: External
– Radioactive particles or other radioactive
materials that adhere to the outside of a body and
are NOT incorporated into the tissues
• Internal Contamination:
– Radioactive materials that are taken into the body.
– Some radioactive materials may be incorporated
into the body tissues
– Some radioactive materials may just “pass
through”
Definitions (3)
• Fugitive Dusts and re-suspension
– Radioactive particles that are on the ground or in
the air and are spread by wind.
– Those that settle and are picked up by the wind
again to re-spread.
• Plume: a generally large “cloud” of radioactive
particles that spread over an area, and the
resulting settling of radioactive particles on
the ground.
Definitions (4)
• Noble Gases: In this context, the radioactive
gases that are found in reactors and as a
product of nuclear weapons. They do not
react with anything and do not form particles.
– Generally short lived (minutes)
– Only a hazard if you are in them!
– Generally only a hazard to skin
• Fallout: Radioactive particles that fall from the
sky, generally associated only with weapons
Definitions (5)
• Fission Products: the radioactive materials
resulting from reactors or weapons
– Generally a wide range of radioactive materials
– MOST are short (minutes) lived
• Radioactive decay/half life: time for half of the
material to disintegrate.
Radiation Dose
• Deposition of energy from radioactive
materials in living tissue
• Many units, some not scientifically correct,
but used anyway
• Lethal human dose if delivered in a short time
(in various units) to the whole body
– 400 rems: 400 rads: 400 roentgens (R)
– 4 Sieverts (Sv): 4 Gray (Gy)
– How many “clicks” on a GM would this be?
Types of Radiation Events
• Radioactive Dispersal Devices
– “Dirty Bombs”
• Reactor Accident
• Nuclear Weapons
Radioactive Dispersal Devices
(RDD)
• Any method used to deliberately disperse
radioactive material to create terror or harm.
A dirty bomb is an example of an RDD.
– It is made by packaging explosives (like dynamite)
with radioactive material to be dispersed when
the bomb goes off.
• GENERALLY
– No fatal doses of radiation
– Only covers “small area”
Reactor Accident
• Accidental release of radioactive materials
from a Nuclear Reactor
– Chernobyl
– Fukushima
– Three Mile Island
• Generally a Dispersal of volatile materials
– over a period of time
– over a wide area
– Lots of time to panic
Nuclear Weapons
• Detonation of a uranium or plutonium based
weapon that yields fission products
– Hiroshima, Nagasaki
• Large amounts of multiple types of radioactive
materials
– Large area involved
– Transported by atmosphere over entire
hemisphere if surface/air burst
Distances from Source Term to
Significant Contamination
• RDD – Not expected to travel far – meters not
miles
• Reactor – May travel meters to miles from
source; Generally lower concentrations at
distance
– Snow, rain will impact
• Weapon – impact from meters to miles
What to do if: (precautions)
• Know in advance of radioactive plume
• It is currently happening
• Plume has passed
Evacuation
• May or may not be the best action
– Shelter in place for noble gases
– If radioactive contamination expected to be low,
may not be important
• Example: Three Mile Island
– Food, water, shelter for animals may be a problem
– May be very costly
• Always move cross wind or upwind of source
term (release point)
Shelter
• If radioactive particulate anticipated to fall on
livestock
– Move animals under shelter
• ANYTHING is better than nothing
– Use feed that has been kept under cover
• Tarps may be sufficient for most feed (hay)
• If not covered, only upper layers may have radioactive
contamination, lower layers may still be usable
• You may be able to see the radioactive contamination,
depending on the event
– Use water that has been under cover
Shelter (2)
• Keep animals under shelter until plume (cloud
of radioactive contaminants) has passed.
– Remember re-suspension is still possible
• Try to move animals into facilities or pasture
that is not contaminated (upwind)
• Note that if sheltering in place you should
stop unfiltered ventilation
– Any filtering will help
– Filters will be filled with radioactive contaminates
when plume has passed
No Shelter, No Evacuation
• Still possible that animals did not get
contaminated as plumes tend to be
unpredictable
• External contamination levels may be low
– If so, move animals to uncontaminated area and
uncontaminated feed
– Over time, radioactive materials eaten will be
removed by natural processes
– May require extensive monitoring
External Contamination
• Unlikely that animals will “drop dead” due to
radiation, regardless of the event
• Best course may be to leave animals in
contaminated pasture where they were when
event occured
• Limited information on what is effective at
removing external contamination
– Current subject of research at CSU
– May take large volumes of water
– Runoff is contaminated
External Decontamination
• Anti-contamination clothing will cause animal
stress
– Person in “street clothes” to help keep calm
• Small amounts probably not a concern
– Brush/vacuum off
– How much is small?
– May be best to provide clean feed until no internal
contamination
• Not as easy to detect!
– May be able to delay
Internal Contamination
• Animals eating radioactive contamination
– Radioactive particles fall onto plants and water
and are consumed
• Feed animals uncontaminated food and water
– Radioactive contaminants become incorporated
into the tissues
– May take up to three months to remove, or longer
– Must be kept in “uncontaminated” areas
– Droppings will be contaminated
Perception Problems
• “Snowball”
• Euthanizing animals may produce a bigger
problem
– Disposal of bio-rad-waste is expensive
– May not be necessary
• Difficulty in finding slaughterhouse to take
decontaminated animals
– Difficulty in selling decontaminated animals
• Consider alternative uses/markets
Fear and Panic
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Few people understand radiation
Most are afraid, even if decontaminated
Find experts to assist
Unlikely that radioactive contamination will
cause immediate injury to animals (or
humans)
• CSU faculty and staff are available to help!
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References
http://www.euranos.fzk.de/index.php?action=euranos&title=products
http://www-naweb.iaea.org/nafa/news/radioactive-contamination.html
http://www.iaea.org/nafa/dx/emergency/agricultural/index.html
Guidelines for Agricultural Countermeasures Following an Accidental Release of Radionuclides, IAEA
Technical Reports Series No. 363,1994.
Planning Guidance for Response to a Nuclear Detonation, Homeland Security Council, Second Edition, June
2010: http://hps.org/hsc/documents/Planning_Guidance_for_Response_to_a_Nuclear_Detonation2nd_Edition_FINAL.pdf
C. D. Berger, J. R. Frazier, R. T. Greene, B. R. Thomas, J. A. Auxier, Radiological Emergency Manual for
Livestock, Poultry, and Animal Products, IT Corporation/ Radiological Sciences Laboratory, Oak Ridge,
Tennessee 37831, Report Number IT RSL 87 168, December 1987
Survival of Food Crops and Livestock in the Event of Nuclear War, D.W. Bensen, A.H. Sparrow, US. Atomic
Energy Commission, December 1971
USDA Radiological Monitoring Handbook, Agricultural Research Service, Agriculture Handbook No. 246,
1963.
B.J. Howard, N.A. Beresford, G. Voigt, Countermeasures for Animal Products: a Review of Effectiveness and
Potential Usefulness after an Accident, Journal of Environmental Radioactivity 56, 115–137, 2001
R.M. Alexakhin, Countermeasures in Agricultural Production as an Effective Means of Mitigating the
Radiological Consequences of the Chernobyl Accident, Sci. Total Environ. 137, 9–20, 1993
Handbook of Radioactive Contamination and Decontamination J. Severa, J. Bár, Elsevier Science; 1st
edition, December 1, 1991
USDA Radiological Monitoring Handbook, Agricultural Research Service, Agriculture Handbook No. 246,
1963.