Radiation Safety
Protecting America from the Boogeyman
At the Idaho National Engineering Laboratory a forklift
moved a small spent fuel cask from the storage pool to the hot cell. The cask had not been properly drained, so
some pool water dribbled out of the cask as it was moved. Because this was "hazardous
material" , regulations required the contaminated material along the
forklift's path be removed. A trench 2
feet wide and 1/2 mile long was dug and the material hauled away to a safe
storage site for long term burial as hazardous materials. A local paving company was hired to repave
the road. They used slag from the local
phosphate plant in their blacktop, a common practice. When the job was done, it was determined the
natural radioactivity of the slag, an everyday paving product, was higher than
the "hazardous material" removed.
Probably only a few hundred thousand dollars wasted.
In 1963 a low level radioactive waste facility was established
in Maxey Flats KY. It was closed in 1975
because ground water contamination was found in nearby streams. The most volatile substance disposed there
was Tritium. Sampling nearby streams revealed average tritium levels at 1.2pCi/mL
during 2001. Assuming surface water at this location could be used as a
drinking water source with a mean annual activity of 1.2 pCi/mL, an individual
consuming 730 liters of water per year would receive an annual radiation dose
of 0.06 millirem per year. The U.S. EPA
public drinking water standard is 4 millirem per year. Average background levels in the US are 300
mRem per year. Many salad oils, which
contain natural potassium -40, have higher radiation levels than this. This site is part of the superfund cleanup,
and cost over $100 million
In America, and throughout the world, there is a vast assortment
of government , professional and non-profit organizations dedicated to
protecting us from radiation. Since the
1950s, the regulators have been producing official documents, estimating
dangers and issuing regulatory standards for every aspect of radiation. Non-profit organizations, often under the
guise of environmentalism, have been campaigning and fund raising for the last
50 years to help rid the world of radiation.
I believe they have amplified the theoretical risks
far out of proportion to the real world risks, contributing greatly over time
to the public's misconceptions about radiation.
And, in the case of non-profits, they tend to confuse or intentionally
blur the lines between low level radiation, nuclear power and nuclear weapons.
As mentioned in an earlier post, before WWII, there was very
little interest or concern about the public's exposure to radiation. Up until that time, the only guidelines
concerned exposures for medical purposes.
Following Hiroshima and Nagasaki, John Q Public became very aware of
radiation, and a host of misconceptions arose which persist to this day.
It is important to understand that early radiation safety
regulations did not arise in a climate
of scientific curiosity or general concern for public health. They arose in a climate of fear. This fear was intentional. We wanted Japan to fear our weapons and end
the war. The growth of the Cold War and
nuclear proliferation was based on the MAD concept (Mutually Assured
Destruction), which only works if both sides are scared. Those who initially created the safety
standards had to deal with this fear. In
subsequent years, most of the revisions to those standards have been done by
academics and professionals whose livelihood depends on this fear, which could
affect their willingness to accept the risks might be overstated.
Many opponents of useful radiation in our lives, including
many environmentalist, argue that we need stringent safeguards because we have
no sensory organ to detect radiation. "Radiation
is particularly dangerous because there is no warning." If fire threatens, you will see, hear, smell
and feel it, and then try to avoid it. We need careful monitoring, and tight
regulations to protect us from an exposure we would never perceive.
This raises the question, why don't we have a radiation
sense organ? Since before the evolution
of life on earth, there has been radiation.
Man did not invent radiation, he discovered something as old as earth
itself. Life evolved at a point in
earth's history when natural radiation levels were probably 10 times higher
than they are now. Like air and water,
radiation is essential for life. Take
away radiation, and we all die. So why
haven't we evolved a sensory receptor for radiation? Perhaps because we don't
need one. At the levels we see
throughout our lives, it is not a threat, it is just an essential nutrient.
If someone drops an atomic bomb on you, radiation is a
threat. Not as big a threat as the
explosion and the fire from it, but still a threat. (90+ % of the casualties from Hiroshima were from the blast and fire, not radiation.) The biggest threat to us from radiation is
sunshine, and we have great warning system for that, our eyes and sunburn. Except in exceedingly rare circumstances, man
does not need to perceive radiation, because the amounts we receive are no more
dangerous than sunshine. None-the-less,
there are many people and organizations
dedicated to the control of radiation, and many trying to eliminate it from our
lives. (Which is both an impossible goal, and a lethal one.)
Radiation Protection, a brief history
Roentgen discovered X-rays in November, 1895, and reported
his discovery to the world in January 1896.
Within a year, it was being used for medical purposes. By 1900 it was apparent that the overexposure
to X-rays could produce skin burns.
Basic tenants of radiation safety such as limiting exposure, collimating
the X-ray beam such that only the area of interest was exposed, and filtering
the weaker rays out of the beam were all being advocated. 10 years after their discovery, basic
techniques of X-ray protection were well known, but their use was spotty. Even after the British Roentgen Society in
1915 and the American Roentgen Ray Society in 1922 both adopted radiation
protection recommendations, many machines were still being used with little or no
protection techniques.
The potentially harmful effects of radioactive materials,
such as uranium and radium were realized much faster. Both Becquerel and Curie developed small
burns from carrying samples in their pockets.
Interestingly, at the same time users were becoming more aware of the
potential risks, the public's fascination with all things related to radiation
was growing. Radium and radon were being
added to everything imaginable in search of a cure for whatever was ailing
you. Radium clinics, radium laced patent
medicines and radon baths all became popular.
In 1928 the Second International Congress on Radiology
adopted the roentgen as the standard measure for quantifying radiation. This was made possible by the development of
reliable X-ray tubes with reproducible outputs, and ionization chambers for
measuring outputs. From this time on,
exposures and acceptable levels of exposure to radiation would be quantified
more precisely.
Also in 1928, H. J. Mueller published his work with
Drosophila fruit flies, showing that large doses of radiation had genetic
effects on fruit flies. Following Muller's work, interest in radiation effects
shifted from short term to long term effects such as carcinogenesis and genetic
mutations.
In 1929 the United States Advisory Committee on X-ray and
Radium Protection was formed. Made up of
professionals predominately involved in the medical uses of radiation, it's
regulations primarily involved medical applications. The committee's second report in 1934 dealt
more with radium protection. It also set
some of the earliest quantitative dose limits for radiation workers, 0.1 R/day
(100 mRem).
In 1941 the National Bureau of Standards published Handbook
H27 "Safe Handling of Radioluminous Compounds." Here again a dose limit of 0.1 R/day was
proposed. This document also proposed
the first limits for an ingested radionucleides and the maximal permissible air
levels in a working environment . These
limits were based in part on the information gleaned from the studies of the
radium dial painters. It was found that
only those who actually licked their paint brushes and ingested significant
quantities of radium had adverse effects.
Once the process of "tipping your brush" ceased, so did the
adverse effects. The standard, 10
picocuries of radon per liter of air, is still generally accepted.
The Manhattan Project (development of the atom bomb) in the
early 40s led to a whole new era in the field of radiation protection. An atomic bomb (unlike a nuclear power
plant--more later on this) requires highly purified and concentrated
radioactive material (plutonium) to generate the rapid reaction required to
produce an explosion, rather than just heat.
As scientists developed the processes to produce this purified product,
they also required devices and guidelines to monitor the associated radiation
and protect themselves as they worked.
These were high levels of radiation, exposures you and I will never
see, and a whole new chapter on
radiation exposure effects and protection was written.
Following WWII, as public awareness and fear grew, the
research results from the Manhattan Project were released. The United States Advisory Committee on X-ray
and Radium Protection morphed into the National Commission on Radiation
Protection (NCRP), issuing 19 reports between 1949 and 1960. The acceptable levels of exposure for workers
in radiation fields was gradually lowered to 5 Rem (5,000 mRem) per year.
In the 40s the US Public Health Service(PHS) began mass
tuberculosis chest X-ray surveys, and in the process entered the field of
radiation protection. They recruited
physicists and eventually developed the Radiological Health Handbook, a source
of radiation biology information for anyone involved in radiation
protection. In 1959 PHS created a
Division of Radiological Health, which now has regulatory responsibility,
assigned by Congress, for ensuring public safety in the medical applications of
radiation.
America is not alone in the field of radiation regulation
and protection. Every major country with
nuclear capabilities also has at least one regulatory agency involved in the
process. On an international level there
are also committees such as UNSCEAR, the United Nations Scientific Committee on
the Effects of Atomic Radiation. While
often different in their area of focus within the vast field of radiation, this
alphabet soup of radiation regulatory bodies has a couple of significant
similarities.
First and foremost, they all base their regulations on
the Linear No Threshold concept. We
discussed the LNT in an earlier post. It
is the concept that no dose of radiation can be considered safe, and that all
doses in our lifetime are cumulative. It
is biologic nonsense, since we evolved in and spend our entire life in a vast
pool of radiation, but it does simplify the regulatory process. Now that we have such sensitive devices for
detecting radiation, the concept of keeping exposure at zero has become
increasingly difficult and expensive.
Nuclear power plants are an
excellent example of the fallacy of regulations based on this concept. Nuclear plants are constantly monitored both
within the plant, and surrounding the plant for very low levels of radiation. The slightest variance is cause for plant
shut downs and usually a blitz of media alarms about radiation exposure from
the plant. Literally billions of dollars
are spent keeping the level of radiation around a nuclear power plant
imperceptible. Ironicaly, burning coal,
in addition to pouring toxic amounts of mercury, sulfur and carbon monoxide
into the air 24/7, also releases radiation.
Not dangerous amounts of radiation, but measurable amounts. If a nuclear power plant measured radiation
output levels anywhere near those found surrounding a coal burning plant, it
would be closed.
Another concept common among
regulatory bodies and particularly embraced by anti-radiation activists is
population dose, or dose commitment.
This is an extension of the LNT.
If one assumes that all radiation is cumulative, and the effects are
passed down through generations via genetic mutations, one can make some very
alarming statements. Helen Caldicot, a
very prolific writer and serious radiation phobic can say about the Chernobyl
event, "As many as half a million
people could be condemned to die of cancer or leukemia, or to be born
genetically deformed, as a result of this catastrophe." I agree it was a disaster, but the actual
toll is more like 200, not 500,000. The
big number comes from the concept of population dose. I will come back to Dr. Caldicot in a later
post.
UNSCEAR, the UN committee did just such a calculation,
estimating the total dose from Chernobyl between now and infinity spread over
the northern hemisphere of the earth at 600,000 man Svc. This large, terrifying number really scares
people with radiation phobia, like Dr. Caldicot. What is ignored is the fact that no one
person outside the reactor got a significant dose. The actual dose to individuals was on the
order of 0.005 mSv. This is a trivial
dose, far less than one gets on a short plane ride. A trivial dose to an individual dies with
that individual. It does not accumulate
in that person or the next generation.
If population dose was true, we would all be dead now from the
accumulated background doses since the dawn of man, not to mention the 1000
nuclear weapons tests performed in the 50s and 60s.
The costs of all this regulation and exaggeration of risks
is extremely high. Dr. Zbigniew
Jaworowski, former member of UNSCEAR and
a professor at the Central Laboratory for Radiological Protection in Warsaw,
Poland wrote in Physics Today in
1999, "Each human life hypothetically saved in a Western industrial
society by implementation of the present radiation protection regulations is
estimated to cost about $2.5 billion.
Such costs are absurd and immoral--especially when compared to the
relatively low costs of saving lives by immunization against measles,
diphtheria, and pertussis, which in developing countries entails costs of $50
to $99 per human life saved. Billions of
dollars for the imaginary protection of humans from radiation are actually
spent year after year, while much smaller resources for the real saving of
lives in poor countries are scandalously lacking."
Anti-war, anti-nuclear,
anti-radiation, anti-everything
Following the first use of
nuclear weapons to end WWII many people were horrified by the new force that
had been unleashed. Shortly after WWII
President Eisenhower unveiled the peaceful atom program, with the hope of
providing cheap clean energy throughout America. However, the cold war developed into an insane
nuclear arsenal race based on the principal of Mutually Assured
Destruction. The peaceful atom took a
back seat to the explosive one--way back.
This was a deplorable time in the history of our country. Throughout the world many organizations arose
in opposition to nuclear weapons and the entire MAD concept. While it has taken some time, we are now in
the process of reversing the decisions of that time.
Unfortunately, many people and
organizations tend to confuse nuclear weapons, nuclear power and the peaceful
uses of low level radiation. While they
might realize these are distinct fields, the perception of risk is lumped under
radiation. And, more specifically,
man-made radiation. As mentioned in the
chapter on risks, our current cultural bias places far more risks on anything
man-made. We love organic. This is somewhat ironic, given that our
lifespan has doubled on the basis of man-made materials.
In the 60s and the 70s this
blurring of the risks became very popular.
Personalities and stars who were know to be anti-war (especially the
Vietnam War) took up the cry of "No More Nukes." While initially aimed at nuclear weapons,
this slogan passed over to the field of nuclear power. Stars like Jane Fonda and Crosby, Stills,
Nash and Young, who were logically opposed to nuclear weapons, were illogically
opposed to nuclear power. They had an
irrational fear of all things radioactive and their potential harm. The public outcry from this radiation-phobia-induced
mass hysteria helped end the growth of nuclear power in America, which these
same zealots probably saw as a victory.
What it produced was an exponential growth in our burning of fossil
fuels with the destruction of millions of acres of pristine land for coal
mining,a rise in the morbidity and mortality of chronic lung disease, and the acceleration of global warming.
What a victory.
I think the people caught up in
these phobic movements had their heart in the right place, but I have my doubts
about some of the organizations.
Charitable organizations are businesses.
They value growth, power, influence, money and whatever their cause
célèbre. Organizations like the Sierra
club and Greenpeace have raised a lot of rent money preaching the horrors of
all things radioactive. These are not
dumb people. They must have volunteers
or staff people smart enough to realize that calculating or propagating the
statement that 53,000 Americans would get cancer from Chernobyl is not only
clearly stupid, but scientifically and morally corrupt. No American is going to get cancer from
Chernobyl, any more than they are from the same dose in a bottle of salad oil.
Natural radiation levels on earth range from below 1 mSv to
over 280 mSv per year, and humans have been doing just fine in these exposures
for eons with no detectable health effects.
The greenies would encourage you to fear a potential dose of 3 or 4 mSv
from a manmade source such as a power plant or waste facility, because they
know you will support and contribute to those trying to alleviate that which
you fear. There is no reason to fear low level irradiation, and no reason to spend valuable resources trying to eliminate it or "protect" ourselves from it. Man exist because low level radiation makes it possible. It is an essential nutrient.
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