It has been about a month since the 3rd anniversary of the Great East Japan Earthquake and the resulting Tsunami that devastated that part of the country, and damaged the Fukushima-Daiichi power plant. And true to form the folks who don’t understand radiation are screaming about government coverups. You see the government of Japan has recently reopened some of the areas that were evacuated after the disaster. And then it comes to light that the doses from residual radiation in the effected area are in the range of 1 millisievert per year. After reviewing several sources in the media, the best number I can find is “more than 1 millisievert per year, which for a story about a scientific subject is really pretty poor. (Is it 1.000001 mSv/a or a million? Both are more than 1. My guess is that it’s closer to the former.)
In the US, normal radiation exposure is between 4 and 6 millisieverts (mSv) per year. (Depends on who is counting and what is considered…) If you move to the Colorado plateau, you will receive more radiation than a low-lander, about .4 to .5 mSv per year due to the fact that there is less atmosphere protecting you on the plateau, than on the beach. Take a job as a flight attendant, you will get an additional 1.5 to 1.7 mSv per year. More if you specialize in long, international flights. If you live in a stone or brick or cement dwelling you will get more than someone living in a wood dwelling. If you work in a government building or a bank surrounded by lots of fancy marble or granite, you will have a higher exposure. (It is small, relax – I live in a brick dwelling.)
Now if you live in other parts of the world, the exposure from natural background radiation can be more or less. In some places much more. (Some places in Europe, the Middle East and the Indian-subcontinent can see exposures from background radiation which approach 10 times what they are on average in the US)
Now can you see why the 1 millisievert per year number in the Fukushima exclusion zone is a none-issue?
The smallest dose positively known to cause an increase risk in cancer: 100 millisieverts per year.
The insanity about radiation (there is even a new Godzilla movie with which to celebrate it!) revolves around the “Linear no-threshold dose hypothesis” of managing radiation. It was adopted by the so-called international community in the 1950s. The only problem with it is that it has no basis in the science. Radiation, like so many things in life, is a question of degree, not of kind. “Jumping off a chair is no big deal. Jumping of a cliff can be a problem.” Both are about jumping and falling. Do you see the difference?
You cannot escape from radiation. It rains down on us from outer space. It is in the food you eat. It is in you. It is no cause for alarm.
Sure, radiation can cause problems, but if you assume that because we can measure it, it is a problem you are kidding yourself. We can measure stupidly small amounts of radiation. Doubt it? Take a look at this diagram. As for you and your food, consider the Banana Equivalent Dose. (Don’t stop eating bananas. I had one yesterday, and half of one with my breakfast today. They are a good source of potassium – which is why they are radioactive.)
I was going to file this under Media Bias, but it isn’t so much that they are biased, they are just completely stupid, and running like the sheep they are.