I have worked as a chemist my entire working career my interest in this is solely from a scientific fact perspective. However I am an advocate of nuclear power as I think it is part of the ultimate solution to our global warming problems. Fukushima has thrown a large monkey wrench into the debate over nuclear safety and because of this I happen to have read on this issue heavily and may be able to offer my opinion on this issue from my little corner of the world.
First off there is radiation all over the Pacific Ocean, some undoubtedly is from the Fukushima accident and some remains from nuclear testing done many years ago and some rises up naturally from deep within the core of the earth. But there are many types of radiation and they all exhibit something called a half life. What a half life is, is the decay of a radioactive atom giving off radiation as it works its way to a stable form where radiation is no longer emitted. Every atom that is a potential source of radiation has a specific half life, or the time it takes for the atom to give off half of its radiation. The studies done of radiation in the oceans are looking for cesium-134 and cesium-137 as both were given off in the Fukushima event. The thing is the cesium-134 has a half life of 2 years, cesium-137 stays around much much longer. If they were to find cesium-134 it is a definite smoking gun and Fukushima would definitely be the culprit. So while they have detected some radiation it is all cesium-137 and they have yet to detect any cesium-134. If the source were Fukushima, they would detect both.
Then there is the fact that the levels detected are well below the EPA drinking water standards anyway. The beautifully colored charts I have seen show an ominously colored cloud working its way across the Pacific as it leaves its traces of radiation in its wake. If you look further you can see that the units of these graphs are a unit called a Becquerel which is a measurement of radioactive decay per second typically per cubic meter of water. The EPA puts the drinking water limit for this radiation at 7000 something Becquerels, the graphs are showing this cloud moving along and the concentration is a low of 7.5 and a high at 100. Don't get me wrong, the EPA number isn't something I would be using for shower water should it approach the 7000 limit but even at 100 Bq/M3 is less than 1.5% of the EPA limit. The EPA is NEVER that far off.
In addition to the effects of the water borne radiation you should check out something much closer to home which is called the Denver Dose. It turns out that Denver Colorado has a particularly high natural radioactivity emitted from naturally occurring uranium in the rock. People living in Denver get an extra dose of 300 millirem per year. Figures reported from Fukushima were using the units of millisieverts so using the same figures the good people of Denver get a dose of 3 millisieverts per year just from living in Denver. After the Fukushima disaster, newspapers reported levels of 1 millisievert per year and considered that a hot spot. 1 millisievert is in excess of what required mandatory evacuation from Chernobyl. But the odd thing is that the good people of Denver have a lower cancer rate than the average city in the US. So what does that 1 millisievert mean? I am a science guy, I believe in data, good data from reliable sources which can be scientifically verified. The Denver dose is an example of what everyday Americans that we can relate to live with every day with no apparent effect. And there is a long standing background of analytics to back this up. Unfortunately policy and regulatory levels can be made up of hype which cannot be backed up with good science.
This is one of those topics that newspapers love to print but the reality of it is that the real issue with nuclear power plants is what to do with their waste. The releases at Fukushima were largely from the spent nuclear waste storage that lost its supply of cooling water. Here in the US we have spent billions of taxpayer dollars developing Yucca mountain to deal with the waste and have since come up with every reason under the sun not to use it. We should use the best available science to find a safe way to store this type of waste and a way to transport it there and allow the nuclear plants to be built to produce power with no carbon emissions. The science supports nuclear as a green alternative, the sensationalists, well they just piss me off!
