What a bunch of wooeee.
The situation at Fukushima Daiichi while concerning isn't catastrophic as some keep trying to claim. The fuel rod pools aren't going to catch fire unless they somehow get drained and then some insane person jumps in and sets off a thermite charge as it takes close to 2,000 C to ignite the zirconium cladding. And even then the effects will still be local as a study done at Lawrence Livermore shows.
Fukushima disaster: New information about worst-case scenarios.
By the last three days of March, the computer modeling produced results that settled the debate: A plume delivering radiation doses exceeding U.S. standards would come no closer to Tokyo than 75 miles, so Americans should stay put. In an April 1, 2011, email to Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, Holdren spelled out details. "Our optimism, such as it is ... comes not from any assumption that the situation at Fukushima is under control but rather from modeling that shows the worst-plausible releases from one or more reactors at Fukushima would not cross [the U.S. guidelines] in Tokyo even in the event of adverse weather," Holdren wrote. "Only with big releases from the spent-fuel pools, combined with even more perverse weather than [the scientists deemed realistic], could the [guidelines] be crossed in Tokyo, and even then, according to the modeling to date, not by much," so "even in these extreme circumstances, sheltering in place might be all you'd want to do."
So even if the fuel rod pools did by some highly unlikely circumstance catch fire, it's very unlikely that even Tokyo would need to be evacuated, people who talk about the end of the world from this are experts in psuedo, not actual science.
And while the radioactive material leaking into the ocean is a local concern, it's not going to have a noticeable impact the farther you get from the coast of Japan. The radioactive isotopes in question are in solution and entering a body of water of over 600 million km^3. We're talking about kgs of cesium-137, cesium-134 dissolved into a vast volume, the concentration is so low it doesn't have a harmful effect.
Bluefin Tuna Radiation: Is There A Health Risk?
First, the elevated levels still remain well below the U.S. government's regulatory limits. And, as Brenner explains, we already get a great deal of radiation exposure in our foods, all naturally occurring. In fact, according to the data, rates of caesium-137 and caesium-134 are 35 times less than the amount of radioactive potassium, which is naturally-occurring in the fish. Radioactive potassium, along with polonium-210 are the two most common and largest radioactive compounds in our foods, but even these give off far less radiation than other natural sources we are exposed to on an annual basis: radon, which occurs naturally in soil and rock, and cosmic rays.
People, and everything, are already radioactive, an average sized person has about 40mgs of Potassium-40 which produces about 10,000 decays a second of which about 10% will produce penetrating gamma rays most of which will pass right through their tissue with no affect.
And the "massive" spike in radioactivity at Fukushima is in a ditch where strontium that was already in the soil was washed into a drainage ditch. It probably makes cleanup simpler now and doesn't raise concerns about serious levels of additional exposure.
Fish might not be the best choice to eat for the next 100 years
Fish are already radioactive, everything is, the levels of cesium-137 and cesium-134 are about 35 times lower than the level considered to be safe.
Let's put this into perspective, there is already about 4.6 billion
tons of uranium in the worlds oceans and about 32,000 tons is added each year. Plus all the radioactive potassium and small amounts of carbon-14 a radioactive isotope produced by high energy collisions in the atmsophere.