No.Farcus wrote:Thank you very much for your efforts! I just grabbed the cyanide nimber from what seemed like a reliable source:Typhoon wrote:If your values for cyanide are correct, then yes.Farcus wrote:Cesium 137 - 44μg/kg body weight. 0.000044 x 50 = 0.0022 = 2.2mg if I weighed 50kg.Typhoon wrote:The Cesium-137 isotope is the one that is of concern.Farcus wrote:
I suppose "A lot of" is a relative term.
Since you seem well informed of the physical properties of many radioactive isotopes, would it be an imposition for you to express the MD50 of the aforementioned Cesium-40 isotope in standard metric mass units for us? You know, kilograms, or tonnes, or what have you?
I'm pretty sure it's poisonous, I just wondered how many kilos of pure Cesium-40 an average person would have to take in to get a lethal dose?
As human death due to Cs-137 is very rare I was not able to find such data.
However, there is animal [dog] data which gives one an order of magnitude estimate:
81 kg [average US male weight] x 44μg/kg = 3321μg ~ 0.003 grams
re: Health risk of radioactive cesiumCaesium-137 reacts with water producing a water-soluble compound (caesium hydroxide), and the biological behavior of caesium is similar to that of potassium and rubidium. After entering the body, caesium gets more or less uniformly distributed throughout the body, with higher concentration in muscle tissues and lower in bones. The biological half-life of caesium is rather short at about 70 days. [13] Experiments with dogs showed that a single dose of 3800 μCi/kg (140 MBq/kg, or approximately 44 μg/kg) is lethal within three weeks. [14]
Accidental ingestion of caesium-137 can be treated with Prussian blue, which binds to it chemically and reduces the biological half-life to 30 days.
A fatal dose of cyanide for humans can be as low as 1.5 mg/kg body weight [an assuredly lethal dosage is significantly higher] .0015 x 50 = 0.075g = 75mg.
So Caesium-137 is approximately 34 times as lethal by weight as cyanide?
http://www.hc-sc.gc.ca/ewh-semt/pubs/wa ... ex-eng.php
From your above quote, 140 MBq/kg ~ 44 μg/kg = 140 MBq of caesium-137 ~ 44 μg of cesium-137 (MD100 for 1 kg of dog/human)
Tepco says the combined incidents at Okuma released 360,000 TBq of cesium-137 into the atmosphere alone (no numbers for ocean and groundwater release).
http://rt.com/news/fukushima-chernobyl- ... ation-145/
By the above formula, that's enough to MD100 71428571kg of human. About 1 million 71kg human beings.
So 1 fraction of the atmospheric release from Fukushima is enough poison (caesium-137) to kill about a million people?
Wouldn't that suggest that Japan has released a lot of poison into the world lately?
By this line of argument, plants are deadly as they release enough CO2 at night time to kill millions*.
Number of deaths due to radiation poisoning from Fukushima Daiichi: 0
Number of deaths due to Tohoku tsunami: 15,878
Note the log scale.
More Cs-137 was released into the atmosphere by the above ground nuclear tests of the 1950's.
*The key point is concentration [Bq/litre] or [Bq/m^3] in the case of radioactive isotopes and [mol/m^3] in the case of other gases.
The world, fortunately, is a very big place.