Voici la question qui me guide dans mes recherches...

L’appât du gain manifesté par les entreprises supranationales et certains groupes oligarchiques, de même que le contrôle des ressources naturelles par ceux-ci, dirigent l’humanité vers un nouvel ordre mondial de type féodal, voir même sa perte. Confronté à cette situation, l’être humain est invité à refuser d’accepter d’emblée une pseudo-vérité véhiculée par des médias peut-être à la solde de ces entreprises et groupes. Au contraire, il est invité à s’engager dans un processus de discernement et conscientisation afin de créer sa propre vérité par la confrontation de sa réalité nécessairement subjective à des données objectives, telles que révélées par la science, par exemple.

The penalty that good men pay for not being interested in politics is to be governed by men worse than themselves. - Plato

dimanche 25 septembre 2011

Low level radiation and Linear no threshold (LNT) theory. We should revisit our regulation.

We should revisit our exposure regulations because our regulatory history is founded on a deception.
Some background first.
What is radiation? According to wikipedia:
In physics, radiation is a process in which energetic particles or energy or waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing. The word radiation is commonly used in reference to ionizing radiation only (i.e., having sufficient energy to ionize an atom), but it may also refer to non-ionizing radiation (e.g., radio waves, heat or visible light).

So what concerns this article will be about ionizing radiation. Again from wikipedia:
Ionizing (or ionising) radiation is radiation with sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, atoms or molecules containing unpaired electrons, which tend to be especially chemically reactive.

Low level radiation.
We know for sure that high level radiation will kill and we know fore sure that low level radiation does not. High level radiation from a nuclear bomb or exposure to high level of radioactivity from a close source of radiation will kill you from anywhere from an instant to a few days, depending on the amount you receive.

The not so clear debate is with low level radiation. Some argue that there is no safe limit where radiation is safe. Those are the advocate of the Linear no threshold theory or LNT.

There is another school of thought that understand that low level radiation under a certain level is safe and even goes further to say that it can also be beneficial. This is called Hormesis. The theory say:
Low levels radiation, activate the body's DNA repair mechanisms, causing higher levels of cellular DNA-repair proteins to be present in the body, improving the body's ability to repair DNA damage.

Sources of radiation in our day to day life
Radiation is everywhere. From the beginning of the earth to now, we are surrounded in radiation 24 hours per day. Here's the distribution of radiation we absorb every day for different sources.

Source of the information, copy here.

We even have natural radioactivity inside our body in the form of Pottassium-40, from wikipedia:
Potassium-40 is the largest source of natural radioactivity in animals and humans. An adult human body contains about 160 grams of potassium, hence about 0.000117 x 160 = 0.0187 grams of 40K; whose decay produces about 5,000 disintegrations per second (becquerels) continuously throughout the life of the body.
Basic conclusion:
So we are ourselves radioactive and we live in a natural environment immersed in radio-activity.  looking only at those obvious natural sources, we could conclude that humans and animals evolved with radioactivity and "learned" to adapt to it.  We could say that radioactivity is helping our immune system to better cope with external influence and keep our body functioning. We could also conclude that without a minimum level of radioactivity, we would be missing the benefits of keeping the immune system "in shape" and have negative consequences from it.  The same way that to be healthy we need to exercise, our immune system need the exercise provided by this low level radiation.

What level of radiation is OK?
I documented in August 2011 that within a certain range, there is a bio positive impact from radiation and outside that range, the impact is negative, since the immune system is either "sleeping" or overwhelmed.

From the conclusion we saw in the previous sections, this graph seems logical. We live in a radioactive environment, therefore we are between point 2 and 5 of this graph, but according to my investigation, we are closer to point 2 than point 4 (optimum), thus we do not have enough radiation to have the full "benefit" of it.  There are events that happened in the past, where we saw that higher than the "normal - closer to point2" level of radiation, where beneficial.

1984 - Taiwan cobalt-contaminated steel
An extraordinary incident occurred 20 years ago in Taiwan. Recycled steel, accidentally contaminated with cobalt-60 (half-life: 5.3 y), was formed into construction steel for more than 180 buildings, which 10,000 persons occupied for 9 to 20 years. They unknowingly received radiation doses that averaged 0.4 Sv—a “collective dose” of 4,000 person-Sv

Studies 20 years later showed that the cancer rates of this population was lower than the unexposed population in the same region.

This shows that this population, exposed to higher level of radiation, but within a limit that the immune system could cope with, got a long term benefit of having an immune system more in "shape" and able to kill off cancer cells as they grew old.

Today's regulation on low level nuclear radiation.
We now have evidence that the "linear no threshold" (LNT) of low level radiation as no scientific proof and all regulation that we have now are not based on sound science.

Here's a copy of an article published in Science News on Sept 20, 2011. Highlights added

No Safe Level of Radiation Exposure? Researcher Points to Suppression of Evidence On Radiation Effects by Nobel Laureate:

University of Massachusetts Amherst environmental toxicologist Edward Calabrese, whose career research shows that low doses of some chemicals and radiation are benign or even helpful, says he has uncovered evidence that one of the fathers of radiation genetics, Nobel Prize winner Hermann Muller, knowingly lied when he claimed in 1946 that there is no safe level of radiation exposure.
Calabrese's interpretation of this history is supported by letters and other materials he has retrieved, many from formerly classified files. He published key excerpts this month in Archives of Toxicology and Environmental and Molecular Mutagenesis.
Muller was awarded the 1946 Nobel Prize in medicine for his discovery that X-rays induce genetic mutations. This helped him call attention to his long-time concern over the dangers of atomic testing. Muller's intentions were good, Calabrese points out, but his decision not to mention key scientific evidence against his position has had a far-reaching impact on our approach to regulating radiation and chemical exposure. 
Calabrese uncovered correspondence from November 1946 between Muller and Curt Stern at the University of Rochester about a major experiment that had recently evaluated fruit fly germ cell mutations in Stern's laboratory. It failed to support the linear dose-response model at low exposure levels, but in Muller's speech in Oslo a few weeks later he insisted there was "no escape from the conclusion that there is no threshold." To Calabrese, this amounts to deliberate concealment and he says Stern raised no objection. 
Calabrese adds, "This isn't an academic debate, it's really practical, because all of our rules about chemical and low-level radiation are based on the premises that Muller and the National Academy of Sciences' (NAS) committee adopted at that time. Now, after all these years, it's very hard when people have been frightened to death by this dogma to persuade them that we don't need to be scared by certain low-dose exposures." 
Within a year after Muller and his group persuaded the NAS to accept the linear model for gonadal mutations, the practice was extrapolated to somatic cells and cancer. Twenty years later, NAS adopted the linear approach for chemicals. Soon thereafter, the U.S. Environmental Protection Agency announced it would use the linear model for risk assessment, Calabrese points out. 
Some can accept that even the most distinguished scientists have human failings, he acknowledges. But his view is that "the regulatory research community needs to hear about this. The implications of my findings are that we should revisit our exposure regulations because our regulatory history is founded on a deception. We have seen literally hundreds of thousands of cleanup decisions based on a model that was fraudulently derived. I think we should probably have drastically different exposure standards today, and far less fear."
Calabrese believes, "The die was cast by Muller and regulations adopted since then have gone unchallenged. I think he got his beliefs and his science confused, and he couldn't admit that the science was unresolved. So he went ahead and expressed an opinion about how to handle the public health situation." 
Geneticists in the 1950s came to embrace the "linear dose-response model" of risk because at the high exposures they tested, there was no level below which DNA damage did not occur. They felt medical doctors didn't grasp how significant were the dangers. As the smartest and brightest, Muller anticipated the risk of atmospheric atomic testing and became passionately committed to protecting society, Calabrese explains. 
Muller and Curt Stern had done many of the key experiments. Muller himself served on the NAS's Biological Effects of Atomic Radiation (BEAR) committee, through which the linear dose-response approach to risk assessment became firmly entrenched. The two successfully suppressed last-minute evidence from the fruit fly experiment conducted in Stern's lab by postdoctoral researcher Ernst Caspari, and the rest is history, Calabrese says. It marked the "transformation of a threshold-guided risk assessment to one now centered on a linear dose-response." 
"To me this all raises the question, what happens when a scientific field lies to the public, to federal agencies and the president? It's a very scary situation that the radiation genetics community in the 1950s assumed that something was correct without requiring the necessary documentation to support it," the UMass Amherst toxicologist says.
Stern's group published a paper in 1947 not long after Muller's Nobel Prize acceptance speech in which they tried to discredit their own study, further evidence of a deliberate cover-up, Calabrese says. "It's been hidden in the bowels of the Atomic Energy Commission for decades until I found it. They revised it to remove the one sentence suggesting this experiment might provide evidence for the threshold model." 
"One could argue that Muller single-handedly undermined above-ground atomic testing, which is a good thing," Calabrese says. "But after uncovering this lie, I'm starting to contemplate what society would have looked like if the regulatory community had felt free to use a threshold model. Members of that 1956 NAS BEAR committee didn't see the domino effect of their actions on our society. Muller's impact on the world of today is almost incalculable. He couldn't have imagined it. But we shouldn't have to live with it."
What are the impact of this regulation, not based on real impact of low does radiation?
The impacts are too numerous to count, but some come to mind.
  • Fukushima nuclear plant fear and exclusion zone
    • Many thousands have been forced out of their homes in the exclusion zones.  This could probably be avoided. Here's a report on this situation.

  • Nuclear power plants regulations that cost billions and slow down projects
    • Today, we impose so many regulations on nuclear power that in the end, projects are abandoned or take 15 years to complete and cost billions more. 
    • Today's coal plants release more radio activity than nuclear power!
    • Going to the doctor for an x-ray, will expose you to higher doses of radiation than working in a nuclear power plant for a year.
  • Countries that shutdown nuclear power plants or stop new projects based on fear alone
    • We see that now with Germany, Japan and other countries.
    • The impact is that they will burn more fossil fuels and have a greater impact on the environment.
  • Possible benefits of low radiation preventive therapy that could save millions from cancers.
    • We now see some cancer researchers using low does, whole body exposure to boast the immune system before a radio therapy treatments.  This help the body recover faster and give better chances to the patients.
The list goes on, like Calabrese said:
Muller's impact on the world of today is almost incalculable

Related links and documents

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