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PostPosted: Nov 16, 2013 2:14 pm 
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The more I'm learning about the health effects of ionizing radiation the more I'm starting to understand the significant disservice that's been done for decades over how radiation is presented widely. Even the kind of radiation exposure that can cause Acute Radiation Syndrome isn't always fatal as you'd expect from the hysteria that often accompanies the subject of nuclear power and reactors and spent fuel pools.

There were 134 cases of ARS diagnosed with people exposed to high levels of radiation at Chernobyl during the accident there, of these 28 died soon afterwards. By 2001 14 more had died from causes that can't be conclusively linked to exposure to radiation.

http://www.ncbi.nlm.nih.gov/pubmed/18049222

When you look at the likely positive effects from low dose exposure to ionizing radiation then it turns conventional wisdom on it's head and makes the kind of regional, national and international reactions to events like Chernobyl and Fukushima ridiculous. It's likely the up-rooting of thousands of people around Chernobyl had far more serious negative effects than the radiation release could ever possibly have.

http://www.world-nuclear.org/info/Safet ... -Accident/

Quote:
In February 2003, the IAEA established the Chernobyl Forum, in cooperation with seven other UN organisations as well as the competent authorities of Belarus, the Russian Federation and Ukraine. In April 2005, the reports prepared by two expert groups – "Environment", coordinated by the IAEA, and "Health", coordinated by WHO – were intensively discussed by the Forum and eventually approved by consensus. The conclusions of this 2005 Chernobyl Forum study (revised version published 2006i) are in line with earlier expert studies, notably the UNSCEAR 2000 reportj which said that "apart from this [thyroid cancer] increase, there is no evidence of a major public health impact attributable to radiation exposure 14 years after the accident. There is no scientific evidence of increases in overall cancer incidence or mortality or in non-malignant disorders that could be related to radiation exposure." As yet there is little evidence of any increase in leukaemia, even among clean-up workers where it might be most expected. However, these workers – where high doses may have been received – remain at increased risk of cancer in the long term. Apart from these, the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) says that "the great majority of the population is not likely to experience serious health consequences as a result of radiation from the Chernobyl accident. Many other health problems have been noted in the populations that are not related to radiation exposure."

The Chernobyl Forum report says that people in the area have suffered a paralysing fatalism due to myths and misperceptions about the threat of radiation, which has contributed to a culture of chronic dependency. Some "took on the role of invalids." Mental health coupled with smoking and alcohol abuse is a very much greater problem than radiation, but worst of all at the time was the underlying level of health and nutrition. Apart from the initial 116,000, relocations of people were very traumatic and did little to reduce radiation exposure, which was low anyway. Psycho-social effects among those affected by the accident are similar to those arising from other major disasters such as earthquakes, floods and fires.


One of the reasons that nuclear power is so expensive is this unrealistic drive to prevent any "contamination" from NPPs when people have been living for millenia in regions that far exceed any industry standards on safe levels of exposure to ionizing radiation. These include Ramsar, Iran, Kerala, India and some areas in Brazil. Not to say that important standards shouldn't be in place, but that they should reflect realistic risks, not hysteria that often can have a political or economic motivation separate from broader interests.

http://en.wikipedia.org/wiki/Guarapari

People have also enjoyed the healing effects of radium and radon saturated waters in health spas since antiquity without even realizing it. Not only does nuclear power make sense from an economic and environmental standpoint, it's also the safest form of power based on the evidence, not the kind of hysteria that often occurs in opposition to plans to develop this crucial sector.


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PostPosted: Nov 16, 2013 9:27 pm 
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Here is some good data on effects of low level exposure.

http://www.belleonline.com/newsletters.htm

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PostPosted: Nov 18, 2013 9:50 pm 
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You really have to wonder why some people are being cited as experts when it comes to safety and nuclear power.

Arnie Gundersen is often used as a source for the media and yet his credentials seem pretty shaky as Ron Adams found.

http://atomicinsights.com/was-gundersen ... -licensee/

From what I can find he's only been licensed to operate a 100 Watt training reactor and yet he's widely quoted on things like the risk with current projects to render the Fukushima plant safe.

http://rt.com/news/fukushima-fuel-clean ... ation-522/

Quote:
Arnie Gunderson, a veteran US nuclear engineer and director of Fairewinds Energy Education, told Reuters that "they are going to have difficulty in removing a significant number of the rods," especially given their close proximity to each other, which risks breakage and the release of radiation.

Gundersen told Reuters of an incredibly dangerous “criticality” that would result if a chain reaction takes place at any point, if the rods break or even so much as collide with each other in the wrong way. The resulting radiation is too great for the cooling pool to absorb – it simply has not been designed to do so.

"The problem with a fuel pool criticality is that you can't stop it. There are no control rods to control it,” Gundsersen said. “The spent fuel pool cooling system is designed only to remove decay heat, not heat from an ongoing nuclear reaction."


From what I understand the possibility of this is pretty much zero, you need a specific geometry to enable criticality with the fuel assemblies.

Gundersen and others also negatively comment on things like the AP1000.

Quote:
In April 2010, Arnold Gundersen, a nuclear engineer commissioned by several anti-nuclear groups, released a report which explored a hazard associated with the possible rusting through of the containment structure steel liner. In the AP1000 design, the liner and the concrete are separated, and if the steel rusts through, "there is no backup containment behind it" according to Gundersen.[15] If the dome rusted through the design would expel radioactive contaminants and the plant "could deliver a dose of radiation to the public that is 10 times higher than the N.R.C. limit" according to Gundersen. Vaughn Gilbert, a spokesman for Westinghouse, has disputed Gundersen’s assessment, stating that the AP1000's steel containment vessel is three-and-a-half to five times thicker than the liners used in current designs, and that corrosion would be readily apparent during routine inspection.


Certainly safety is an issue with nuclear power plants, but the civilization and even world ending scenarios that some "experts" come up with seem to be mostly motivated by an over-hysterical application of the LNT taken to ridiculous lengths. Even with the worst accident so far, Chernobyl, the death toll is in the hundreds at most and that's with a reactor that emitted about 5% of its core, something that almost certainly won't occur ever again.

If regulations were based on the actual risk you have to wonder how much easier and less expensive it would be to get certification and build the number of NPPs we need to replace coal in the coming decades.


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PostPosted: Nov 18, 2013 11:04 pm 
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Aren't fuel pools borated?

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PostPosted: Nov 19, 2013 3:09 am 
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Smoking causes death.
The adverse health effects from cigarette smoking account for more than 440,000 deaths, or nearly one of every five deaths, each year in the United States.2,3,4
More deaths are caused each year by tobacco use than by human immunodeficiency virus (HIV), illegal drug use, alcohol use, motor vehicle injuries, suicides, and murders combined.3,5
If nobody smoked, one of every three cancer deaths in the United States would not happen.2
Smoking causes an estimated 90% of all lung cancer deaths in men1,2 and 80% of all lung cancer deaths in women.1
An estimated 90% of all deaths from chronic obstructive lung disease are caused by smoking.1,2


Compared to smoking, stacks of metal in japan do not bother me at all.

Hell, japan was nuked twice by America, releasing huge amount of radioactive dust into the air.

Am I, an american, am supposed to be worried about metal inside a sealed reactor building??????


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PostPosted: Nov 19, 2013 3:15 am 
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KitemanSA wrote:
Aren't fuel pools borated?


I never heard of one that used this. Far simpler to have clean water and put the neutron poison in the fuel racks. I'm not sure but I think all densely stacked pools do this, with less densely stacked pools using just water space for subcriticality but it is less common since it takes up more space (does mean good air cooling in a drainage accident though).


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PostPosted: Nov 22, 2013 5:01 pm 
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KitemanSA wrote:
Aren't fuel pools borated?


I was thinking you could use boric acid as an emergency backup if there actually was a criticality issue with fuel pools, but it would be a corrosion issue with continuous use.


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PostPosted: Nov 22, 2013 7:02 pm 
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There's also a lot of concern raised about the flow of cooling water into the Pacific off of Fukushima, but this report shows how quickly the radionuclides are diluted to very low levels even a few kilometers off the Japanese coast.

http://www.iaea.org/newscenter/news/201 ... 291013.pdf

The idea that as the radioactive isotopes are spread out the dose rates drop rapidly seems to escape some of the anti-nuke commentators so they seem to treat the release of them from Fukushima as a biological hazard and not a radiological. viruses and bacteria can multiply out in the environment, but the more you spread out radioactive material the less of a hazard it is, to the point where it's probably a health benefit if you look at some of the links like Kiteman posts.

There's simply no way that even the worst case accident at Fukushima of all the fuel pools catching on fire could come close to the claims being made simply from the reality of spreading the radionuclides out enough to get the coverage needed. And if most of that material ended up in the Pacific which is likely given the dispersion of the release from Fukushima already then the material would soon be in such low concentration it would produce little real risk.


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PostPosted: Nov 23, 2013 3:04 am 
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DougC wrote:
The idea that as the radioactive isotopes are spread out the dose rates drop rapidly seems to escape some of the anti-nuke commentators so they seem to treat the release of them from Fukushima as a biological hazard and not a radiological. viruses and bacteria can multiply out in the environment, but the more you spread out radioactive material the less of a hazard it is, to the point where it's probably a health benefit if you look at some of the links like Kiteman posts..
It doesn't have to spread far from a radiation standpoint. But with some isotopes, like Sr90 there is a bioaccumulation issue for radiation and for Cs137 there is a bioaccumulation issue for what appears to be an inability to handle the transmutation product, barium 137. The body has had billions of years to evolve pathways to handle the Ca40 transmutation product for K40. Not so much for Ba137. I don't know of any studies that show hormesis on Cs137. But it is good that there is a simple chelation agent for Cs137.

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PostPosted: Nov 23, 2013 4:55 am 
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Cs-137 has a very short biological half life, so it is very difficult to accumulate large amounts of Ba-137 in the body. The Cs will pass out before it can become Ba-137.

Cs-137 can be considered purely a chronic, external dose emitter. The least dangerous type. I don't know why people freak out over it, as there hasn't been a single documented case of Cs/Ba-137 deaths from Chernobyl. Deaths were caused by the really short lived stuff for emergency workers, and iodine later on.

The only effect seen is that Cs-137 radiophobia scared the wits out of the surrounding population, and even entire countries full of gullible people like Germany. The result was great stress and damage done, people becoming alcoholics and smoking excessively, not having children because they thought they were doomed and were even told this, literally, by the authorities (!). There was one interview of a woman who was evacuated, she lived in constant fear of "having a sort of radiation".


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PostPosted: Nov 23, 2013 3:00 pm 
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From what I've seen it takes about 70 days for radioactive cesium to clear the body and it's mostly distributed throughout the body so it's probably not going to collect in specific sites as with iodine-131 and Strontium-90. They've studied people coming out of the Chernobyl region and found no real issues with cesium.

http://www.ncbi.nlm.nih.gov/pubmed/7790202

Quote:
Abstract
Of the 500,000 immigrants from the former Soviet Union who came to Israel during 1990-1993, about 100,000 are estimated to have come from radiocontaminated areas near Chernobyl. These people were subject to chronic uptake of environmental radiocesium over protracted periods. During October-November 1991, a joint Israeli-Canadian investigation measured radiocesium body burdens in immigrants to Israel from the Ukraine, Belarus, and the southern Russian republic in order to provide factual information on radiocesium levels to concerned immigrants and to relate the body burdens to the geographic area of residence before coming to Israel. Assessments were made of 137Cs body burdens in 1,228 volunteer men, women, and children. These measurements were accompanied by medical assessments based on clinical histories and examinations. Radiocesium levels were strongly dependent on the duration of residence in Israel, with the highest levels being found in the most recent immigrants. The maximum level, extrapolated back to the time of leaving the former Soviet Union, was estimated to be about 0.83 kBq (10.3 Bq kg-1). Of the most recent immigrants from the Kiev region (< 101 days in Israel), only 15% had back extrapolated body burdens > 50 Bq, whereas 53% of those coming from Gomel and other towns in the contaminated zones (> 3.7 x 10(10) Bq km-2 of radiocesium) had detectable levels > 50 Bq. People coming from the latter region had significantly higher body burdens as compared to those from the former, in accordance with the higher degree of ground radiocesium contamination reported for the latter region. Women and children showed considerably lower total radiocesium content in comparison to men. All radiocesium body burdens at the time of measurement were too low to be of health concern.


There were several thousand cases of thyroid cancer in the Chernobyl region that have been attributed to Iodine-131 released but some of those may have turned up due to much better screening, one thing the accident did do was increase the attention paid to health in the area. Soviet authorities dd little to prevent the consumption of contaminated milk which is a basic precaution to protect against exposure to the short lived Iodine-131 and Sr-90 exposure can be limited by identifying contaminated soil and either cleaning it up or preventing agriculture there. And as Kiteman states there is treatment for certain exposures such as Prussian Blue for cesium, so this idea that even a major accident like Chernobyl is a death sentence for thousands isn't supported by the evidence.

Nuclear accidents don't have the health risk of chemical accidents like happened at Bopal or with the serious risk posed by some biological organisms but they often get treated that way in stories generated by groups opposed to continuing development of nuclear power.


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PostPosted: Nov 23, 2013 5:11 pm 
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Here's the EPA sheet on cesium-137, I question how accurate this is when it comes to health effects.

http://www.epa.gov/radiation/radionucli ... fecthealth

Quote:
Like all radionuclides, exposure to radiation from cesium-137 results in increased risk of cancer. Everyone is exposed to very small amounts of cesium-137 in soil and water as a result of atmospheric fallout. Exposure to waste materials, from contaminated sites, or from nuclear accidents can result in cancer risks much higher than typical environmental exposures.


Where is the actual evidence that exposure to all radionuclides results in an increased risk of cancer?

The studies I've looked at indicate at certain exposures you get a decrease in cancer from ionizing radiation, not an increase, the EPA must be following the LNT when doing risk assessment.

From what I'm getting from looking at the actual evidence, there is very little risk from radiation >10mSv per year and that likely goes as high as 100mSv per year, with good evidence for hormesis at low levels. The NSWS showed that worker exposed to mostly gamma radiation from cobalt-60 decay, which has a higher energy than cesium-137 decay, showed a decreased mortality and a decrease in occurrence of radiation sensitive cancers.


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PostPosted: Nov 23, 2013 6:39 pm 
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There is no evidence for that at all. The authorities just keep repeating it till people believe it, including themselves.

If you are an authority then there's a power game. The Church had maintained that the earth was the center of the solar system for centuries. Anyone who questioned this, even with great scientific evidence, challenged the authority of the Church. So they were burned at the stake. Science or not was irrelevant. Challenging authority was the key blasphemy.

We're still in those middle ages when it comes to radiation effects. Many scientists have shown proof that LNT is completely wrong especially on chronic doses (the only type of dose relevant to nuclear power plants even in accidents). They are simply excommunicated or ignored with bad excuses on methodology (the latter is particularly ironic considering the Japanese bomb survivor data is methodologically inappropriate for determining chronic doses). The only difference is that the scientists aren't burned at the stake, so we must have had some progress.


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PostPosted: Nov 24, 2013 2:32 am 
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I can find few sources, and can't re-find some that I read, but what I have read is that Cs accumulates in muscle tissue at a fairly high factor (20:1 type of numbers). This is not sufficient to engender radiation damage issues at the kinds of environmental levels at issue. But there is another issue besides radiation, what happens to the decay product in the biological scheme of things. If a biochemical had Cs137 in it and all the sudden has Ba137 instead, what does that do to biochemistry? Certainly it is an issue that should be studied.

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PostPosted: Nov 24, 2013 5:16 am 
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The Wiki entry on barium says the following.

http://en.wikipedia.org/wiki/Barium

Quote:
Because of the high reactivity of the metal, toxicological data are available only for compounds.[23] Water-soluble barium compounds are poisonous. At low doses, barium ions act as a muscle stimulant, whereas higher doses affect the nervous system, causing cardiac irregularities, tremors, weakness, anxiety, dyspnea and paralysis. This may be due to the ability of Ba2+ to block potassium ion channels, which are critical to the proper function of the nervous system.[24] Other target organs for water-soluble barium compounds (i.e., barium ions) are eyes, immune system, heart, respiratory system, and skin.[23] They affect the body strongly, causing, for example, blindness and sensitization.[23]

Barium is not carcinogenic,[23] and it does not bioaccumulate.[25][26]


Muscle stimulant... that's interesting, considering the notion that Cs concentrates in the muscle, and we are talking about truely tiny doses here (in radiation sense already, so certainly in a chemical sense).

Note that barium does not bioaccumulate. Neither does cesium. It concentrates in muscle tissue, but that is not the same as bioaccumulation; if you regularly take cesium it will concentrate in the muscle, but when you stop taking in cesium it will quickly pass out of the body.


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