Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: daveid66 on 19/03/2011 03:02:20

Title: Hiroshima/Nagasaki Long-Term Global Impact?
Post by: daveid66 on 19/03/2011 03:02:20
What has the ecological and epidemiological impact been from the Hiroshima and Nagasaki bombings in 1945, not limited exclusively to Japan, but globally?  What about the effects of all the tests performed by the US and USSR during the cold war?  What are the radiation levels emitted by the Japanese nuclear reactor relative to the aforementioned events?
Title: Hiroshima/Nagasaki Long-Term Global Impact?
Post by: yor_on on 19/03/2011 19:40:54
The observable effects of the bombings was to the people living there then, and the land they lived on, but it is more or less gone now, sixty five years later. There is though a statistically proven genetic damage, as I understands it, that still seem to follow those unfortunate, and their descendants. But as it seems random, only found if looked at over a longer period of time, comparing it to a control population, it's easy to miss.

But there are all kind of bombs, dirty and clean, bombs made to kill only biological life etc. We humans have no end to our imagination. When it comes to Russia they have areas that really should be left unpopulated containing a lot of radioactive waste. But as those living there have no way to go? They stay and have stillborn babies instead. Their old government lied to them, amongst other forbidding the doctors to write radiation as the cause on any death certificate, and as for the new one? Those living there haven't been relocated yet, as far as I know? USA had some atomic bomb testing done too, also keeping quiet, well, maybe also not realizing the long term implications of radiation? Security come in all manners and the atom bomb was, and is, still classified material. I remember reading something of it a long time ago, but they have nowhere near the radioactive wastelands Russia created.
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Most of the later 'testing' was done in under earth caves, custom built for the purpose, limiting the amount of radioactive contamination in the atmosphere. The real problem is the wastes the civilian nuclear plants produce and the way we store it. Nobody wants it near themselves, that is, if they have any common sense :) And as you can see when governments try to build new 'waste facilities',  those propositions mostly backfire as soon those living there gets to know about it. The way we treat, or rather not treat, the waste is our real problem. Having nowhere to move it may make your 'power plant' a bigger risk than anticipated.

"The Fukushima Daiichi plant has seven pools for spent fuel rods.  Six of these are (or were) located at the top of six reactor buildings.

One “common pool” is at ground level in a separate building.  Each “reactor top” pool holds 3450 fuel rod assemblies.  The common pool holds 6291 fuel rod assemblies.  [The common pool has windows on one wall which were almost certainly destroyed by the tsunami.]  Each assembly holds sixty-three fuel rods.  This means the Fukushima Daiichi plant may contain over 600,000 spent fuel rods."
Title: Hiroshima/Nagasaki Long-Term Global Impact?
Post by: syhprum on 19/03/2011 20:00:15
There seems to be a psychological effect although most of the victims were blown to pieces or burnt to death the propaganda machines have spread the tale that radiation is the big killer.
The result a few micro sieverts leads to the panic buying of Iodine tablets and a hysterical fear of nuclear power stations. 
Title: Hiroshima/Nagasaki Long-Term Global Impact?
Post by: yor_on on 19/03/2011 20:36:33
Well, there is no short term effects even if you would get radioactive winds. A one time concentrated dose above 3000 MsV will cause internal bleeding and death as I understands it, but as far as I know we don't really know the long term effects of weak radiation accumulating over a longer period. I read somewhere that we've had constantly raising radiation-levels in the atmosphere since tour 'atomic era' started.

Chernobyl is another example.

"The first announcement on Soviet television came two days later, twelve hours after high levels of radioactivity were detected in Sweden and Finland. Radioactive fallout polluted natural ecosystems and human food sources in large portions of Europe and the USSR. There were measurable amounts throughout the Northern Hemisphere. For example, an increase of 6,574 picocuries per liter of rainwater recorded on May 12 in Washington State was more than 140 times the background level measured immediately before the Chernobyl cloud reached the USA. Soviet authorities knew what had happened, however, and took actions of various kinds. Although winds at first carried the plume of radioactive pollution westward toward Europe, a later shift in weather patterns carried a dangerous cloud toward Moscow.There are reports that the Soviet Air Force seeded the clouds to precipitate the radionuclides before they could pass over the capital. Whatever the cause, large amounts of this material fell on the western section of the Bryansk Region, in the area around and to the west of the city of Novozybkov, where levels of soil contamination well above forty Curies per square kilometer have been confirmed. Novozybkov is about 175 kilometers (110 miles) northeast of Chernobyl."

And

"a survey of soils in the Bryansk Region, showed that there was considerable contamination of agricultural lands by cesium-137 over an area of 720,200 hectares (1,779,600 acres), or about forty percent of the total. In addition, about 415,400 hectares (1,026,500 acres) or thirty-five percent of the very extensive forests were contaminated. The three most important radioisotopes studied were cesium-137, which behaves chemically much like potassium, strontium-90, which resembles calcium, and iodine-131. Living tissue readily absorbs all three of these elements. A number of other radioisotopes came down in the fallout. Cesium-137, the most prevalent long-lived pollutant, has a half-life of 30 years, which means that half of the amount of that isotope deposited in the fallout from Chernobyl will still remain in the year 2016, and one-quarter in 2046.

It is not easily leached out of soil by water. During the six years after the accident, it tended to persist in the upper layer of soil. A Ukrainian study showed that in undisturbed forests, more than ninety percent of the amount originally measured remained in the top fifteen centimeters (six inches) of forest litter and soil. Strontium-90, with a half-life of 28.8 years, is more mobile in the environment, and very dangerous to vertebrates because as an analog of calcium it collects in the bones and bone marrow, and may cause leukemia. Iodine-131, the substance released in the largest quantity at Chernobyl, has a half-life of eight days, but is extremely dangerous due to its tendency to lodge in the thyroid gland and ovaries. Other studies showed that some radioisotopes were readily absorbed by plants, and affected forest trees in many ways. Dr. Zhirina had begun dendroclimatological studies of the forests in the Bryansk Region before the accident, and was therefore able to make comparisons of the situation before and after."