First off I would like to thank Libradex for letting me post this here. I am a liberal on this conservative site, but clearly this tragedy transcends political boundaries.
I'd like to start out by saying I'm not a nuclear scientist; I have just read the news like everyone else. If any of my numbers or assumptions are incorrect, PLEASE let me know by posting a comment; I will correct it immediately.
I plan on updating this article and others in the coming days.
You are not being told the real story on Japanese radiation. Whether this is arrogance from the Japanese government, a fear of causing panic, some cultural element, or simple incompetence; we might never know. But this lack of truth-telling is harming the Japanese people around the Fukushima nuclear power plant, and will cause irreparable harm to countless lives in the area.
The evacuation ordered on March 11th was in a 20km area around the damaged Fukushima power plant.
Just today, the Japanese government urged a VOLUNTARY evacuation within 30-km around the plant.
The question is: why make it voluntary? If the area is safe, why ask people to leave? If it's not safe, why not force the evacuation? The equivocation on this will cause needless deaths from cancer. Areas beyond 40km should be immediately evacuated.
I don't say that to incite panic, but to save lives. People within at least 40 km from the plant are in danger from exposure to radiation.
Lots of statistics and numbers have been floating about, without any context. Becquerals, sieverts, rads, what does it mean? Well, how about calculating the % chance people will die from cancer, given a certain exposure to radiation; that's really the only numbers we care about. If there isn't any health risk to the radiation, who cares about it? Likewise, if the radiation DOES cause health effects, we need to know about it. Who has those statistics? The EPA does right here.
This EPA document calculates the % chance one will get FATAL cancer from a variety of factors: how long you're exposed, how much radiation, the element in question (Iodine, Cesium, Plutonium, etc.), whether it's from ground contamination, water, air, etc. It's all there.
So yes, below we're going to calculate the % chance of contracting FATAL cancer due to THIS radiation. These fatalities will not come now, the EPA has calculated the LIFETIME chance that someone will get fatal cancer. It might be 1 year, 5 years, 20 years from now. But the cause of the cancer WILL be this radiation, according to the EPA. There are separate stats for getting cancer, but the stats below are for fatal instances of cancer.
So let's calculate some radiation, some 40 km from the nuclear plant. The source of the data is here:
"The ministry also said it had detected 1.17 million becquerels of radioactive iodine and 163,000 becquerels of cesium per kg of soil in samples collected in Iidate, Fukushima Prefecture, 40 km from the nuclear plant, in a survey it conducted Sunday."
It's barely mentioned, at the bottom of the story. Minor detail, right? Let's see.
1.17 million becquerals is 1,170,000 becquerals. According to the EPA document, to get the mortality rate for Iodine-131 for soil we should multiply:
1,170,000 Bq/kg * 0.000000000000000928 kg/Bq-s to get 0.00000000108576 / s. What is that number? It represents the number of (eventual) fatalities per second someone is exposed to this radiation.
0.00000000108576 / s. Looks like a small number, and it is. Let's start carrying it out:
0.00000000108576 / s = 0.000003908736 / hour = 0.000093809664 / day. Still a pretty small number, but in reality it is 1 in 10659. In percentage terms it is .009%. What that number means is that every single day, that 1 in 10659 will get FATAL cancer from this radiation. In 10 days 1 in 1065 will get fatal cancer. etc. And that is just from Iodine.
Iodine has a half-life of 8 days; this means it gets half as radioactive after 8 days, then 1/2 again in another 8, etc. If the leakage from Fukushima is contained, radiation from Iodine will stop. With Cesium, we aren't so lucky. The half-life for Cesium-137 is 30 years.
Let's calculate the fatality rate from Cesium-137.
163000 Bq/kg was found in the soil. Multiply that by 0.00000000000000157 to get 0.00000000025591 /s. That's how many incidents of fatal cancer to expect / s. A very small number. But when we carry it out, it's 0.000000921276 / hour, and 0.000022110624 /day. That's 1 in 45227 every day eventually contracting a FATAL cancer. After 10 days it's 1 in 4522. After 100 days it's 1 in 452. After 1000 days, around 3 years, it's 1 in 45. That's more than 2% of the entire population getting cancer after only 3 years. And Cesium's half-life is 30 years.
We need to add them together, to get 0.000115920288 / day, or 1 in 8626 people every day will contract fatal cancer from this radiation. In 10 days it will be 1 in 862. In 100 days it will be 1 in 86. In 1000 days it will be 1 in 8 people that will contract fatal cancer.
And in this article we're not even considering radiation from the air, or from food/water. This is just contamination from soil alone.
Now, that's assuming that the radiation levels remain constant, which hopefully they will massively decrease. Even so, given Cesium's long half-life, we can assume that a good % of this radiation will remain in the area for decades. It will be on buildings, on top of cars, on roads, on temples, etc. It will cover the entire town.
This does not merit panic; the problem is not the short-term but the long-term effects of this radiation. Citizens need to know this. But what Japan should do is plan an orderly evacuation of the surrounding area, to at least 40 km (where this reading was taken). It shouldn't be a recommendation, it should be mandatory. The downside of people panicking does not outweigh ignoring the issue and subjecting countless infants, children, and adults to radiation every day.
Japan needs to test and everyone needs to be told of total radiation exposure in all the surrounding towns within at least 75km. The Japanese people are a strong people; minimizing the real long-term threat by not giving them information will just add to their suffering needlessly.