phaster wrote:To understand why there is danger w/ nuclear fall out first requires understanding what radiation is,... and a good place to start is to think about a heat lamp
(heat_radiation_lamp).jpg
(the bulb) is an example of something the produces an emission of energy, in this case heat from a source
what makes nuclear power so attractive is the ability to extract lots of "energy" from a vary, vary, vary tiny source!
so imagine dry talc powder as an analog for radio active material, in other words picture each tiny grain of talc powder as having the ability to give off the same amount of energy as a heat lamp
https://www.youtube.com/watch?v=ba79P5Qzfrswhat makes nuclear fall out dangerous is ponder inhaling an individual grain of talc powder which then gets stuck in your lungs,... basically the key idea is to ponder what would happen if ya had your skin exposed to a close by 250 watt heat lamp (i.e. skin on human body gets a "radiation" burn)
http://www.gettyimages.co.uk/detail/vid ... /502266422nuclear fallout is what sort of inspired the character godzilla, as well as made the USA and USSR to rethink the wisdom of exploding bombs above ground
now back to your question,... if you think about what happened in chernobyl and fukushima, here lots of "energetic" particles like dry talc powder was scattered in the environment (and dispersed by wind/ocean-currents) when the pressure vessel of the nuclear reactor exploded
now do you grasp the bad consequences of nuclear fallout?
anyway looking at todays paper, just read something interesting about a self proclaimed environmentalist
Pro-nuclear activist running for governor on pledge to reform utilities commissionShellenberger listed eight key pledges he said would lower energy costs, reduce poverty, improve education and promote cleaner sources of power. His first pledge is: “Break up the corrupt California Public Utilities Commission (CPUC), release secret emails and prosecute the criminals.”http://www.sandiegouniontribune.com/new ... story.html
https://www.ted.com/talks/michael_shell ... nvironmenthttps://www.youtube.com/watch?v=ciStnd9Y2akIMHO if we as a people wish to continue having all the consumer goods and life style stuff associated the so called "american way of life" we'll need "clean" base line power like nuclear because the weather changes (i.e. the sun does not always shine AND the wind does not always blow)
also FWIW,... the reason high pressure reactors (like Diablo Canyon or San Onofre here in california) were built is because the military paid for the R&D AND the fuel for pressurized water reactors could be re-packaged for military applications (i.e. things that make a BIG BANG!)
as it stands we "humans" are @ an interesting cross road, its going to be interesting to see what path we take
Your heat lamp analogy is a false analogy in the extreme.
People have this nonsense idea that when a highly radioactive particle falls to the ground it remains highly radioactive for eons, or at least generational human lifetimes.
Nothing could be further from the truth. Presume your scenario of breathing in a contaminated dust mote is correct in all its initial parameters, you breathe in the dust and for some bad luck reason in lodges in your lung tissue instead of being expelled by mucus secretion as normally happens.
Okay now what you have this tiny radioactive source in your lung. Two main short lived isotopes exist that could be on that dust mote lodged in your lung if the fallout comes from a recently running reactor or a nuclear explosive device. These are Iodine 131 with a half life of 8 days and Cesium 137 with a half life of just over 30 years. The iodine decays away to effectively stable isotopes in 5 half lives or 45 days and ceases to be radioactive rapidly over that time frame. The Cesium does the same thing but because its half life is a human generation you will still have 25% of the radioactivity trapped in your lung 60 years later which makes you elderly in every culture and if you were 30 when the event happened you are very elderly or died of something else already by the 60 year mark.
For a dust mote trapped in your lung tissue just about any isotope with a half life longer than 30 years is irrelevant from a radiation point of view. In simplest terms if something has a 200 year to 2 billion year half life and you are eating a spoonful every day from the time your parents start you on solid food you will never notice the radioactivity because it will decay little to very very little within your human lifespan.
So for your heat lamp analogy, to get that much energy release from a particle the size of a lodged dust mote the half life has to be very short, like a pure sample of Iodine 131 instead of the little bit that would coat a dust mote. So lets say the evil luck of your cursed life caused the particle to be somehow pure short lived isotopes all with half lives of a few weeks at most. Say 6 weeks or less because any longer on such a point source and the energy release becomes nothing like your heat lamp, it is more like moonlight.
So in five half lives or 5*6 = 30 weeks your dust mote is effectively inert. Yes that is less than a year and in point of fact radioactivity studies at Fukushima completely confirm this fact of physics.
The emissions immediately after the accident were around 220 billion becquerel; readings declined after that, and in November and December 2011 they dropped to 17 thousand becquerel, about one-13 millionth the initial level.
IOW in just 9 months the fallout radioactivity radiated away so much that only 1/13,000,000 particles remaining were radioactive. Now a dust mote, tiny as it is contains trillions of atoms and I specified your dust mote was a pure sample. So for easy math say it had 13 Trillion atoms in the mote. 13 Trillion/13 Million reduces the radioactivity particle count to just 1 Million radioactive atoms remaining out of the original 13 Trillion. In a pure sample with a six week half life that becomes 500 thousand in six weeks, then 250 thousand after another six weeks and 125 thousand after another rapidly winding all the way down to 2, 1 and 0. I didn't bother to run the entire progression but you can easily do so by putting your assumed number of atoms in a calculator program and just keep dividing by 2 until you get to less than 1. Count how many steps that took and multiply it by the half life of the sample, in this case six weeks. At the expiration of that period the radioactive material is no longer radioactive, it is inert.
But WAIT you say, all the fear mongers and MSM are always going on and on about Plutonium with its 24,900 year half life! Yes, yes indeed they are. But stop and reflect for a moment, if that dust mote were a sample of pure Plutonium 239 and it was permanently lodged in your lung tissue for 100 years after you inhaled it how much radiation damage would it do to you?
Math again darn it! 100/24,900 = 0.004 or 4 out of every 1000 atoms will have decayed in 100 years. Okay so say for easy math the sample was that same 13 Trillion atoms we used for our earlier sample of short lived material.
13 Trillion/1000 is 13 Billion atoms. Multiply by 4 to get 52 Billion decay actions over 100 years. Sounds like a lot when said that way doesn't it? But the math isn't finished at that point. 100 years times 365.248 days times 24 hours times 60 minutes times 60 seconds is 3,155,742,720 seconds in 100 years unless I dropped something somewhere. 52 Billion/3.155 Billion = 16 atoms decay every second for that 100 year span. Holy cow how are you still alive? Oh wait, your own body is vastly more radioactive than Plutonium 239!
The amount of the radioactive isotope 40K in a 70-kg person is about 5,000 Bq, which represents 5,000 atoms undergoing radioactive decay each second. Second, 40K emits gamma rays in a little over 10 percent of its decays and most of these gamma rays escape the body.
IOW your natural radioactivity even back when Gargle was thumping Screechy on the head with a club and your next cave neighbors were Neanderthals was 5000/16 = 312 times more radioactive than if they had breathed in a dust mote of pure Plutonium 239 and it became lodged in their lung tissue as you analogized.
Yes lung tissue is sensitive to radioactivity. However your body has natural repair mechanisms to deal with the fact that you are naturally radioactive, and not just from the Potassium 40 (K-40) in every cell of your body. You also have a lot of Carbon 14 in your body because it is part of all growing plants and you either eat plants or eat animals who have eaten plants or other animals that eat plants. The Carbon 14 load in your body gives you another 3,000 disintegration a second to deal with and repair.
In the real world where the laws of physics apply and the biological repair mechanisms of your body are not impaired you can fix several times over your natural radioactivity level of theoretical damage to your cells in your lungs or anywhere else. That does not mean the theoretical 6 week half life dust mote used in the example earlier is totally harmless, it simply means that because its danger period lasts less than a year your body is highly likely to repair whatever damage it does rather than those damages accumulating to the point of causing a malignancy and killing you prematurely from cancer.
To know if radiation is dangerous you have to know how energetic it is, how much you are exposed to, and how long that exposure lasts. For fallout the MSM and fear mongers hype to the rafters the bulk of the activity by a huge margin is less than a year, and in the event of a nuclear explosion of pure material is measured from hundreds of tests to be about 14 days. That is reality. The famous boat full of Japanese fishermen exposed accidentally during the pacific testing program were injured because they were exposed to fresh fallout that had only been decaying a few hours when the weather deposited it on their boat. If the weather had done the same thing even as little as a day later their exposure would have been much less, and by the time the weather deposited the fallout on land the activity level was relatively low and decreasing rapidly.
Last point before I finish. Your premise is based on a dust mote of radioactive material lodging in your lung tissue. The thing is your lungs are very very good at dislodging dust and transferring it by mucous excretion up your trachea to the point where it is expelled at the esophagus opening and swallowed. From there it gets processed through stomach acid so your body can absorb any minerals deemed useful for cell biology. That is where the real 'threat' from bio-accumulators like Cesium 137 and Iodine 131 comes from because your stomach and intestinal tract are optimized to absorb Sodium & Potassium which makes absorbing Cesium highly likely and Iodine is absorbed by direct intent because it is a necessary chemical and not common in most food. The Cesium flows through your system for a few days just like the Sodium and Potassium you get in food until you sweat or urinate it out. This makes the 30 year half life crucially important because it rarely stays in your system more than a very few days and rarely undergoes decay while inside your body before being excreted.
Iodine on the other hand accumulates mostly in the thyroid gland which does a pretty good job of retaining iodine in its tissues because it is not common in food and you need it for proper function. If your diet is low in stable iodine this can cause you to absorb and retain enough Iodine 131 to do severe damage to your thyroid gland. If you eat an American diet with iodized salt your thyroid is well supplied with stable iodine and doesn't have a lot of extra space for Iodine 131, or if you take an Iodine supplement when a fallout threat is known or as part of a multi-vitamin/mineral regimen the same thing happens. The biggest tragedy after Chernobyl was the government of the USSR failed to give everyone an Iodine supplement immediately. Many of these people were below the iodine needs of the body so their thyroids absorbed a lot of Iodine 131 and as a result many of them developed thyroid disease or even cancer. The fact of the matter is those injuries were 100% preventable, but the bureaucracy was too slow to respond to the crisis to prevent them. Iodine not needed by the thyroid is excreted so if those people had been supplied with stable iodine they would never have absorbed the Iodine 131 that caused them later health problems.