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Author Topic: does a picture say more than a thousand words?  (Read 86385 times)

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #250 on: 18/10/2013 00:20:47 »
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So it is clear that a single nuclear accident widely offsets any "gains" obtained by using a nuclear plant instead of a coal plant.

I think not.

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The Aberfan disaster was a catastrophic collapse of a colliery spoil tip in the Welsh village of Aberfan, near Merthyr Tydfil, on 21 October 1966, killing 116 children and 28 adults. It was caused by a build-up of water in the accumulated rock and shale, which suddenly started to slide downhill in the form of slurry.

You might also consider the 12,000 people killed in London by coal smog in 1952. I have no idea what the annual coal smog death toll is in Beijing, but it's far from negligible.

Now how may people have been killed by all the nuclear power incidents* in the world, ever? About 60.

As of now, half of the annual population radiation dose in the UK comes from radon (natural emission from the ground), roughly 12 - 15% each from medical (increasing) , food, building materials and cosmic radiation, and about 0.1% (decreasing) from all the nuclear fallout, waste, and other industrial sources. Don't expect me to panic.   

An additional dose of 100 mSv over 5 years does not produce any detectable increase in stochastic harm - it's the basis for the statutory dose limit for radiation workers. It was entirely reasonable to evacuate areas around Chernobyl and to prohibit occupation of areas where the lifetime committed dose could exceed 500 mSv. The area is tiny compared with that devastated by the 2011 tsunami.

*Most important of all, is to remember that Chernobyl was not an accident. It was a deliberate decision by several people to override safety systems and disobey the operating instructions for the plant, which responded exactly as the textbook predicted. I always remember  being shown round the aircraft for my first flying lesson. The instructor said "This is the stall warning indicator. In all the best accidents, you will find that it has been switched off".
« Last Edit: 18/10/2013 00:29:05 by alancalverd »
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #251 on: 07/11/2013 23:37:59 »
Yes Alan, and I agree on that we, as a species, don't seem to worry overmuch for consequences, when developing and trying out new technology. We seem to have an innate trust in our ability to survive, combined with an innate ability to look the other way when evidence start to compile for something not being that smart, as we first thought. And I'm not sure, but I would guess that an lifespan of? Let's say fifty years, could be a average, historically, for mankind? Not sure of course, possibly someone else would know about that?

That's one point.

Another is what background radiation we expect ourselves to be comfortable with over a thousand years, as some short time scenario.

A third should be the way radioactive dust builds up in concentrations through biological accumulation, if it works the same way DDT and other toxins does it's 10 X 10 X etc, accumulating for each part of the food chain. And when I die its journey starts all over again. What I mean is that it will be in circulation for a awfully long time.

A fourth should be at what level of radiation we need to start worrying.

"Guidelines on exposure to low doses of radiation have largely been based on estimated risks from models using data from Japanese survivors of the atomic bombs, where radiation exposures were brief and very much higher. As a result, there have been some long-standing uncertainties about the extrapolation of these risks to low radiation doses.

The researchers conclude that the size of the increased risk of childhood leukaemia with natural gamma-ray exposure is consistent with these models and supports their continued use in radiation protection. The results of the study contradict the idea that there are no adverse radiation effects, or might even be beneficial effects, at these very low doses and dose rates.

The Oxford University researchers, along with colleagues from the US National Cancer Institute, The University of Manchester and the Health Protection Agency, have published their findings in the journal Leukemia."

And then we have those Thorium reactors, I still don't know what to think there? We haven't really tried them yet, have we? And a lot of people seem to have serious doubts about their feasibility. Myself I would prefer to develop natural sources first, then again, I don't mean extracting methane now.
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #252 on: 08/11/2013 00:39:46 »
It reminds me so much of proving that Global warming is a result of man.
So tricky to prove anything, unless you trust statistics?

A starter.

"We have measured 14C from nuclear bomb tests in genomic DNA of human myocardial cells, which allows retrospective birth dating (9-11). 14C levels in the atmosphere remained relatively stable until the Cold War when above ground nuclear bomb tests caused a dramatic increase (12, 13). Even though the detonations were conducted at a limited number of locations, the elevated 14C levels in the atmosphere rapidly equalized around the globe as 14CO2. After the Test-Ban Treaty in 1963, the 14C levels have dropped exponentially, not primarily because of radioactive decay (half-life 5730 years), but by diffusion from the atmosphere (14). Newly created atmospheric 14C reacts with oxygen to form 14CO2, which is incorporated by plants through photosynthesis. By eating plants, and animals that live off plants, the 14C concentration in the human body mirrors that in the atmosphere at any given point in time (15-18). Since DNA is stable after a cell has gone through its last cell division, the 14C level in DNA serves as a date mark for when a cell was born and can be used to retrospectively birth date cells in humans (9-11).Evidence for cardiomyocyte renewal in humans.

Used to have a chart defining how background radiation had raised since the forties, at least I seem to remember me having one? But I can't find it searching the net today? I would dearly like to find a chart for it.

This is another tidbit I found.

"Dr. Jay M. Gould

The illnesses affecting veterans of the Gulf War are all symptomatic of the same immune system deficiencies that have affected the atomic veterans deliberately exposed to the Nevada nuclear bomb tests, Native American miners exposed to uranium dust and indeed the many millions of victims who since the birth of the nuclear age in 1945 have inhaled or ingested radioactive fission products never before encountered in nature. When uranium and strontium-90 are ingested—especially because they have long half-lives—both have immediate and delayed adverse effects on the immune system's response capabilities. These effects were clearly indicated by classified animal experiments conducted by American nuclear scientists as far back as 1943.

The name for this condition is low-level radiation, which has little relation to background radiation from natural causes such as cosmic rays and radioactive minerals in the soil. Over the course of countless millennia, human immune defenses have developed the capacity to resist cancer from such natural sources, only to be overwhelmed in 1945 by the sudden introduction into a previously pristine atmosphere of huge amounts of man-made radiation.

The Department of Energy has recently admitted that in the haste to produce plutonium for the first atomic bombs, the Hanford nuclear weapons complex released 550,000 curies of radioactive iodine in 1945. In terms of picocuries, the unit now used to measure radioactivity in a liter of milk or water, this means that in 1945, one-hundred-fifty million Americans were unwittingly exposed to more than four billion picocuries per-capita of this lethal radionuclide, comparable to releases from the Chernobyl accident—the worst in human history.

This was followed by two decades of atmospheric bomb tests recently estimated by the Natural Resources Defense Council to be equivalent to exploding forty thousand Hiroshima bombs. The effects of this testing were revealed by a sudden epidemic increase in cancer among children five to nine years old. Since 1945, female breast cancer incidence has nearly tripled, and we have established that a significant number of the eighty million baby boomers born in the bomb-test years 1945 to 1965—literally the worst time in history—did in fact subsequently display evidences of the damage to hormonal and immune systems sustained in utero.

We can show that in the period 1945-1965 there had indeed been an anomalous forty percent increase in underweight live births, perfectly correlated with the rise in strontium-90 found in human bone and especially in baby teeth. In fact, it was the concern expressed by mothers, as in the Women's Strike for Peace movement that helped prod President John Kennedy and Premier Nikita Khrushchev to finally terminate above-ground nuclear tests in 1963. There was a brief period of improvement thereafter until fallout from civilian power reactors replaced bomb-test fallout, especially after the Three-Mile-Island and Chernobyl accidents of 1979 and 1986. Since 1979, the ominous rise in the percentage of underweight live births that first surfaced in 1945 has resumed."  Nuclear Testing, Power Plants and a Breast Cancer Epidemic.


And this, a very solid collection of evidence too.

Low Level Radiation: Deadly … Or Harmless?


That's why I'm so interested in low level background radiation. It stays for a long time, it get taken up by all sorts of biological processes, plants etc, as well as animal. And it keeps on after I die, it does not disappear from the 'circle of life' just because I did. If we want to ignore this, a natural consequence seems to become what we then define as a appropriate lifespan, for enjoying ones life, and possibly for keeping a 'modern' civilization?



 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #253 on: 08/11/2013 01:26:23 »
Hmm?

"American physician Brian Moench writes:

    The idea that a threshold exists or there is a safe level of radiation for human exposure began unraveling in the 1950s when research showed one pelvic x-ray in a pregnant woman could double the rate of childhood leukemia in an exposed baby. Furthermore, the risk was ten times higher if it occurred in the first three months of pregnancy than near the end. This became the stepping-stone to the understanding that the timing of exposure was even more critical than the dose. The earlier in embryonic development it occurred, the greater the risk.

    A new medical concept has emerged, increasingly supported by the latest research, called “fetal origins of disease,” that centers on the evidence that a multitude of chronic diseases, including cancer, often have their origins in the first few weeks after conception by environmental insults disturbing normal embryonic development. It is now established medical advice that pregnant women should avoid any exposure to x-rays, medicines or chemicals when not absolutely necessary, no matter how small the dose, especially in the first three months."

Seems I was wrong?
Questioning the idea of a x-ray doubling the cancer risk?
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #254 on: 08/11/2013 03:11:47 »
   
Quote

Yes Alan, and I agree on that we, as a species, don't seem to worry overmuch for consequences, when developing and trying out new technology. We seem to have an innate trust in our ability to survive, combined with an innate ability to look the other way when evidence start to compile for something not being that smart, as we first thought.
speak for yourself! History suggests otherwise, and the adoption of the precautionary principle by the European Union almost killed medical research entirely.

Quote
That's one point.

Another is what background radiation we expect ourselves to be comfortable with over a thousand years, as some short time scenario.
We evolved and live on a radioactive planet. There is no evidence that background gamma doses up to 20 mSv/yr have any impact on life expectancy or birth defects, though I have my doubts about alpha radiation.

Quote
A third should be the way radioactive dust builds up in concentrations through biological accumulation, if it works the same way DDT and other toxins does it's 10 X 10 X etc, accumulating for each part of the food chain. And when I die its journey starts all over again. What I mean is that it will be in circulation for a awfully long time.
There is almost certainly concentration of plutonium in shellfish but no evidence of further concentration higher up the food chain. To achieve this you need to saturate the primary source and all predators need to be dependent on a single source of food. This was certainly the case with avian raptors and DDT but not with fish and shellfish in the Irish sea. 

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A fourth should be at what level of radiation we need to start worrying.

"Guidelines on exposure to low doses of radiation have largely been based on estimated risks from models using data from Japanese survivors of the atomic bombs, where radiation exposures were brief and very much higher. As a result, there have been some long-standing uncertainties about the extrapolation of these risks to low radiation doses.
No longer the case. We now have plenty of really accurate data on high beta and gamma doses from industrial accidents and on low doses from environmental dosimetry, which has replaced estimates and extrapolations from atomic bomb data. The embarrassment is that the "linear no threshold" model is, on the evidence, too pessimistic: it seems a little background radiation does you good, but we are required by law to worry at every level.

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The researchers conclude that the size of the increased risk of childhood leukaemia with natural gamma-ray exposure is consistent with these models and supports their continued use in radiation protection. The results of the study contradict the idea that there are no adverse radiation effects, or might even be beneficial effects, at these very low doses and dose rates.
I'd like a reference to this work, which contradicts everything else I know about the subject. Two problems are (1) Alice Stewart's seminal work on childhood defects and maternal pelvic x-rays used a population of sick mothers and (2) it is very difficult to unravel any concomitant alpha dose from the relatively easily detectable gamma. I am increasingly convinced that the radiation weighting factor for alphas is a factor of 10 too low.

Quote
A new medical concept has emerged, increasingly supported by the latest research, called “fetal origins of disease,” that centers on the evidence that a multitude of chronic diseases, including cancer, often have their origins in the first few weeks after conception

Nothing new about that. Some 40 years ago it was shown that if you back-project the growth of some breast tumors to the size of a single cell, it was present in the fetus. Which is why we now look for (and find) genetic suceptibility to breast cancer. 

Quote
It is now established medical advice that pregnant women should avoid any exposure to x-rays, medicines or chemicals...
Aha! the giveaway trademark of the lunatic fringe. What is "chemicals"? Or more to the point, what is not? Is folic acid a chemical, a medicine, or a useful and proven preventative for spina bifida? Is ascorbic acid a chemical, a medicine, or a vital constituent of fresh fruit?

The observation of an increase in underweight babies between 1945 and 1965 coincides with three sociological phenomena: a rapid increase in women smoking, the dieting fad, and the emergence of pre-and postnatal care that ensured the carriage to term of many fetuses that would have aborted previously.   


Quote
Seems I was wrong?
Questioning the idea of a x-ray doubling the cancer risk?

Why would you x-ray a pregnant woman? Only if you thought she, or the fetus, was sick. So you are starting with an unrepresentative sample.

It's a complicated and fascinating subject!
« Last Edit: 08/11/2013 03:16:34 by alancalverd »
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #255 on: 08/11/2013 12:22:29 »
I am speaking for myself Alan :)

And it was you linking to the way we treated smog and its medical implications for the longest time. Think there is a famous American example of a town, from where people first started to argue that smog indeed was dangerous? Don't have it at hand but I read about it, somewhere?

As for discussing biological accumulations? I don't know there, but if it is contained in what you ingest, or inhale, and if different radioactive substances accumulate in different parts of ones prey, then they should accumulate inside my body too, assuming that they don't get flushed out the natural way. and they should accumulate I think? Just like all other organic/inorganic materials should be able too, if not flushed out or broken down into something else.

As for arguing that a little background radiation is harmless, or even 'healthy'? That's what the links above was all about, and they do not seem to agree with this line of thought? That's what statistics is about as I think, to lift forward those connection we otherwise might miss.

And then we have this.

"“Epigenetics” is a term integral to fetal origins of disease, referring to chemical attachments to genes that turn them on or off inappropriately and have impacts functionally similar to broken genetic bonds. Epigenetic changes can be caused by unimaginably small doses – parts per trillion – be it chemicals, air pollution, cigarette smoke or radiation. Furthermore, these epigenetic changes can occur within minutes after exposure and may be passed on to subsequent generations.

The Endocrine Society, 14,000 researchers and medical specialists in more than 100 countries, warned that “even infinitesimally low levels of exposure to endocrine-disrupting chemicals, indeed, any level of exposure at all, may cause endocrine or reproductive abnormalities, particularly if exposure occurs during a critical developmental window. Surprisingly, low doses may even exert more potent effects than higher doses.” If hormone-mimicking chemicals at any level are not safe for a fetus, then the concept is likely to be equally true of the even more intensely toxic radioactive elements drifting over from Japan, some of which may also act as endocrine disruptors."

Epigenetics is a quite interesting term, long being dismissed as cranky :), but coming back with new evidence for its validity. A strange field indeed. As for "It is now established medical advice that pregnant women should avoid any exposure to x-rays, medicines or chemicals..."

I was thinking that as this research results seem to have been established in the fifties, and that the radioactive doses we use today should differ by a magnitude, one might argue that what was valid then could be questioned today.

And the link you asked for is from the university of Oxford. http://www.ox.ac.uk/media/news_stories/2012/120612.html
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #256 on: 08/11/2013 16:44:35 »
Thanks for the link. You need to read between the lines to discover that there is a statistical correlation but no claim for a causal link. My guess is that the real culprit is alpha radiation. It's a long story but it explains why there are childhood leukemia clusters at Sellafield, Burghfield, Capper Pass (not a nuclear site) and Dounreay, but not at other nuclear sites. Cornwall and South Yorkshire are listed as radon-affected areas and although the Scottish Borders are not the most radon-affected parts of Scotland, they are more densely populated than the worst bits.
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #257 on: 08/11/2013 18:54:51 »
That one you need to explain Alan. Are you considering Alpha particles and radon instead of gamma? Also I read it as the researchers expect "that the association between natural gamma-rays and childhood leukaemia is likely to be causal." But it is a very tricky subject.
=

Keep misspelling :)
Ah well.
« Last Edit: 08/11/2013 19:05:35 by yor_on »
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #258 on: 08/11/2013 21:20:46 »
Here are my thoughts. Not mainstream, but to my mind suffienctly logical to deserve consideration.

Radon is an alpha-emitter. Alpha radiation has a very short range in tissue - it doesn't penetrate the epidermis and low-energy alphas  don't even cross two human cells. But because the alpha particle is massive and charged, it does an enormous amount of damage in a short distance.

Sellafield, Burghfield and Dounreay are the only UK sites that handle quantities of plutonium as bare metal. Capper Pass is a lead smelting plant that releases polonium into the environment.

We know that plutonium is preferentially absorbed into the femur of fetal mice, and produces leukemic babies. The problem with alpha emitters is that they are very difficult to detect unless you know what you are looking for, but in the case of nuclear fuel reprocessing they are always associated with beta and gamma emitters which are easy to detect. So it came as no surprise to discover a statistical link between paternal gamma dose and childhood leukemia among the Sellafield population. Regrettably, trade unions reached a financial compensation settlement based  on measured paternal gamma dose, back in the 1980s, and I think the real culprit, men carrying Pu dust home on their bodies and literally impregnating their wives with it,  was swept under the carpet.

Epidemiology shows a higher incidence of birth defects in Kerala than would be expected if the natural background radiation was gamma, but it is a region with a high concentration of thorium and therefore the anomalous background is alpha. Like Pu and Po, but less so, Th is chemically reactive and can be absorbed into the body in food, by inhalation, or through sexual penetration.   

Radon is an inert gas, so tends to be inhaled and exhaled without entering the bloodstream. However if it is inhaled with active smoke (e.g. fresh tobacco smoke) I think the decay products which include alpha-emitting isotopes of polonium, bismuth and lead, may well diffuse into the blood. So I'd be interested to see the smoking history of mothers with leukemic babies in radon-affected areas of the UK.   

I think the subject deserves rather closer examination.
« Last Edit: 08/11/2013 21:28:55 by alancalverd »
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #259 on: 11/11/2013 20:30:33 »
Interesting. Guess I will have to read up on it Alan. And you definitely have a point with it behaving differently if "inhaled, swallowed, or absorbed through open wounds."

As well as "However, once alpha particle enters the human body, its characteristic of depositing its energy over a short range becomes crucial. Under this condition, the alpha particle is surrounded by the living tissue of human body and the harm arising from such internal radiation exposure2 is mostly confined to the small area of tissue surrounding the alpha particle source. If the alpha particles accumulate in a certain organ, nearly all the energy released by the particles will be imparted to that organ rather than distributed to a larger area around it.  Hence the damages to the cells of that organ by alpha particles are substantially larger.... 

For example, iodine (beta particle and gamma ray emitter) and strontium (beta emitter) tend to accumulate in the thyroid gland and the bone respectively whereas plutonium (alpha emitter) mainly accumulates in the bone and the liver. " From http://www.hko.gov.hk/education/edu02rga/radiation/radiation_07-e.htm


The interesting part is where they accumulate in a human body I suspect? As that should give us statistical clues to what particles we are looking at, studying the types of cancer we find over time.

 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #260 on: 12/11/2013 01:43:06 »
Very much the point. You also need to consider the damage tolerance of the accumulating organ: thyroid tumors are common but usually curable whereas pancreatic tumors are very difficult to treat . The affinity of plutonium for bone is I am sure the reason for childhood leukemia clusters.   

Remember it's not the alpha particles that accumulate, but particles of alpha-emitting nuclides. So although one alpha may only damage one or two cells, a resident microgram of plutonium dissolved and diffused through an organ can do a hell of a lot of damage.
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #261 on: 13/11/2013 11:08:29 »
Took a look at Polonium, a very potent radioactive 'poison', popular in a lot of shady circles. It releases Alpha particles, "The 138-day half-life of 210Po is short, so the element is very radioactive. While it has a melting point of 254°C, it is so radioactive that if you made 1g piece of 210Po it would create so much heat it would melt itself. The liquid would appear to glow blue due to the interaction of the alpha particles with the surrounding air." Now also implicated in Yasser Arafat's death.

Weird planet, isn't it? Disinformation, and killing of things, that seems to be what we excel at. Makes me wonder how we ever succeeded building the technology we actually have, spin-of's from wars, or preparing for them, maybe?:) Nah, myself I think it comes from that stupidly useless theory about Earth, being our 'planet of unlimited resources'. And yeah, I think we've wasted such a lot of those, coming to this point. Also, we don't like the idea of 'renewables ', do we? It shots down any idea of a market economy/society in where we all can become 'millionaires', if we just try hard enough. A greed, or profit, based market economy allows for a lot of things as long as we can relocate, as soon as the resources dry out where we are, but it must on a planet of limited resources, logically end up in a place from where we have nowhere to move at all.

Because that is the overall trend, isn't it? You don't make a profit anymore?
Relocate, and try again..

Anyway, guess it's my age talking here :) Not as full of optimism as I used to be.

"The alpha particle is a helium nucleus (two protons and two neutrons). This relatively large particle will not travel far through air and is stopped by a piece of paper. However, it pulls electrons out of other elements (ionising them). In turn, the ionised elements are highly reactive and able to undergo reactions that would not normally occur in a human body.

So unlike the image of radiation damaging DNA and causing cancer, alpha particles act more like a normal poison, but damaging many different biological systems rather than targeting one type of molecule.

The effects of polonium poisoning are effectively those of acute radiation poisoning. These occur within one day of exposure to a large dose of ionising radiation. The effects are all based on damage occurring to the body’s fast-growing cells:

    bone marrow – a drop in number of blood cells causing tiredness
    gastrointestial cells – causing vomiting and nausea
    follicular cells – causing hair loss. "

On the other hand, you need a nuclear plant I think, for getting it. It's not something you can collect naturally.
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #262 on: 13/11/2013 13:01:31 »
In reverse order

Polonium is a natural radionuclide, discovered by the Curies. It is emitted during the smelting of lead. However it is pretty rare and most of the stuff around today is manufactured in reactors or extracted from nuclear waste. It is used industrially to ionise air in places like paint sprayers and flour mills, reducing the risk of static discharge explosion and improving the spray distribution.   

In fact ionising radiation doesn't "target" DNA. What happens for the most part is that it ionises the water in a cell, and the free radicals thus generated interfere with the hydrogen bonding of mitotic DNA, causing mutation or death of the daughter cells.
There is indeed a certain "normal " level  of such mutation.
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #263 on: 13/11/2013 15:27:57 »
Yep, you're right, Curie was the one finding polonium residing inside pitchblende. "A mineral consisting of uranium oxide and trace amounts of radium and thorium and polonium and lead and helium; uraninite in massive form is called pitchblende which is the chief uranium ore."  http://www.aip.org/history/curie/resbr2.htm

The point here might be how much 'natural radiation' from polonium exist?

"it took Marie over three years to isolate one tenth of a gram of pure radium chloride. For reasons that would not be fully understood until the concept of radioactive decay was developed, Marie never succeeded in isolating polonium, which has a half-life of only 138 days."
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #264 on: 13/11/2013 23:25:46 »
 
Quote
The point here might be how much 'natural radiation' from polonium exist?

Enough to produce a childhood leukemia cluster downwind of the Capper Pass lead smelter. 
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #265 on: 15/11/2013 01:07:23 »
You got any good links Alan?

Found http://www.wiseinternational.org/node/402

What I'm unsure of there is exactly what they mean with.

"The plant operated not just as Europe's only primary tin smelter, but as the recycler of a devil's cauldron of heavy metals and radioactive wastes, including radium and uranium."

So how much tin did they produce? And it was from the tin you got it?
So what do they mean by 'recycling'?
« Last Edit: 15/11/2013 01:13:37 by yor_on »
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #266 on: 15/11/2013 17:34:52 »
Bit of a jumbled sentence, but AFAIK they extracted and possibly recycled lead. Lead is the end product of several radioactive decay chains so whilst recycled lead probably doesn't contain a lot of polonium or uranium, the primary ore almost certainly does. Capper Pass never, to my knowledge, recycled anything classified as radioactive waste, but there have to be permissible exemption limits for radionuclides in ores and scrap metal because everything contains some traces of natural radionuclides even if it was manufactured before 1945. 

Extracting tin from Cornish cassiterite (and probably from other sources) will also generate a fair bit of polonium and other alpha emitters as the surrounding rock is full of radionuclides.

I guess the problem with Capper Pass was its size and location not only in geography but also in time. Primitive smelters tended to be small, close to coalfields, and operated in the days when about 1 in 4 children died before their 10th birthday from pretty well every imaginable cause, so a bit of leukemia would hardly be noticed among the general incidence of consumption, starvation, hypothermia, cholera and congenital syphilis that characterised the good old days of Victorian England. Getting rid of all these irritants, then building a whacking great central smelter upwind of a conurbation, just changed the epidemiologcal perspective so you could spot the leukemias among the devastation.     
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #267 on: 18/11/2013 02:09:15 »
Thanks :)

sometimes those short stories confuse more than they enlighten.
 

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Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #269 on: 10/07/2014 15:55:20 »
This one might be of interest.

UNSCEAR 2013 report systematically underestimates
health impact of Fukushima catastrophe.


I suppose there always will be a cost to new technologies. In unfortunate times human lives. We've had smog, for the longest time argued to have nothing to with the industries creating it, and even if it had, of no specific danger. Coal burning Countries as China find it to be a imminent problem today. To me the question seems to become one of where the cost in lives, and naturally living standards, will force a policy change. Because that is what I see, reading 'between the lines'.
« Last Edit: 10/07/2014 16:10:10 by yor_on »
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #270 on: 20/12/2014 07:40:46 »
Thought this might be of interest. I lost my chart over the natural background radiation years ago :) and I've missed it. Found this today, although, it's no pie chart..

"
 - 1950’s, average background radiation went > 1 mSv (max. public limit for radiation exposure)

- 1960's, Due to 2,400 open air atomic bomb tests radioactive fallout, > 2 mSv
https://www.health.ny.gov/publications/4402/

- 1994, average background radiation, Chernobyl, TMI, other accidents and dumping; > 3 mSv
http://web.mit.edu/newsoffice/1994/safe-0105.html

- 2002, average background radiation, more accidents, spills, ocean/air dumping > 3.6 mSv
http://www.doh.wa.gov/portals/1/Documents/Pubs/320-063_bkvsman_fs.pdf

- 2014, average background radiation, Fukushima mega disaster and more dumping > 6.2 mSv (max. limit for public has been raised 600%)
…the average annual radiation dose per person in the U.S. is 620 millirem (6.2 milliSieverts)."
http://www.epa.gov/radiation/understand/perspective.html



PEAK PACIFIC OCEAN RADIATION READINGS HISTORICALLY

What would have made the background radiation jump up like that between 2002 and 2014?  Here is one possibility;


Event                      Peak Ocean Radiation Reading In Bq/m³

2,400 Nuclear weapons testing peak -                 100 Bq/m³
Chernobyl caused a peak reading of -              1,000 Bq/m³
Fukushima caused a peak reading of - 180,000,000 Bq/m³    "

http://agreenroad.blogspot.se/2014/03/background-radiation-has-increased-600.html
 

Offline alancalverd

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Re: does a picture say more than a thousand words?
« Reply #271 on: 20/12/2014 08:38:57 »
Always read the small print!

Your first quoted paper gives 3 mSv/yr from all natural sources in the USA.

The same figure appears in the second paper, which does not mention Chernobyl at all.

The third paper includes 20% medical radiation as "background" - not what the rest of the world considers to be background at all, and it accounts for almost all of the additional 60 microsievert.

The jump between the third (1994) and fourth (2014) paper is entirely accounted for by medical radiation, which now delivers "on average" 50% of the annual dose to a US citizen.

However as nearly all diagnostic radiation dose is delivered in the last year of life (we don't usually x-ray healthy people) the notion of "average" is very distorted by its inclusion. The sievert, being weighted by radiation and organ factors, is a measure of risk rather than dose, so when dealing particularly with interventional procedures it has to be offset by the risk of not using radiation, and the use of population averaging is inappropriate. If I need a pacemaker, or even more serious, radiotherapy, my radiation dose will be enormous but I will survive another 20 years and you will receive no dose or benefit from the procedure. And I wouldn't want the pacemaker leads to be inserted by knife and fork surgery if there was a decent x-ray machine available.

More germane to your argument: The contribution of fallout and all other manmade nonmedical sources remained at or below 1% of the total throughout the period of reporting.

Sadly, your final reference is just another example of "green = scaremongering bullshit". What a shame. I'm sure there are plenty of well-motivated environmentalists, but the business seems to be run by crooks and liars - these authors certainly don't claim to be ignorant.


« Last Edit: 20/12/2014 09:00:14 by alancalverd »
 

Offline yor_on

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Re: does a picture say more than a thousand words?
« Reply #272 on: 20/12/2014 09:01:33 »
Hmm, have to read the sources there Alan, to see. I was surprised too actually, but I linked it all the same. Wish I had the chart I used to have, to compare between.
 

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Re: does a picture say more than a thousand words?
« Reply #273 on: 20/12/2014 09:22:21 »
Yeah, he seems questionable. That one is a bad reference, I should have checked his sources before linking it. Still, as i have this idea of leaving what I once written 'as is', I'll let it be, to my utter shame :) with this addendum agreeing with you. 
 

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Re: does a picture say more than a thousand words?
« Reply #274 on: 20/12/2014 09:45:18 »
But I still need to find a chart, including man made radiation, defining the increase, preferably up to date. What I'm primary wondering about is the danger related related to fetuses, what seems to be called "fetal origins of disease" according to physician Brian Moench.  http://www.washingtonsblog.com/2013/08/are-the-levels-of-fukushima-radiation-hitting-north-america-harmless.html

 

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Re: does a picture say more than a thousand words?
« Reply #274 on: 20/12/2014 09:45:18 »

 

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