USS Ronald Reaganwas riding athwart in the radioactive discharge plume 10 miles away from the crippled Fukushima plant. The crew desalinated seawater to use it in cooking, with some crewmembers developing cancerous diseases and/or becoming blind as a result.

The contamination of the ocean within the 10-mile zone of the nuclear power plant is due to the fact that some of the reactor nuclear decay products made it to the ocean, rather than to the air, as was the case in Chernobyl in 1986. Currents take harmful agents to great distances, so the seafood and fish that are caught in the contaminated currents even in other parts of the world may still prove a health hazard, says the Deputy Chairman of the State Duma Committee on Natural Resources, Maxim Shingarkin.

"Because of the World Ocean currents, the seafood that's caught off the US Pacific coast is more likely to contain radionuclides than the seafood in the Sea of Okhotsk, which is by far closer to Japan. It is these marine products that may find their way to the tables of different countries' residents that pose the gravest danger," he said.

Contaminated fish may have been caught and delivered anywhere. From now on one should bear in mind that it's impossible to check the entire fish catch for radiation. This is what the co-chairman of the Eco-Protection international environmental group, Vladimir Slivyak, says about the situation in a comment.

"Russia has been considering setting limits on catching marine products and fish in the Far East. But no restrictions have officially been imposed thus far, to the best of my knowledge. But some moves may eventually be made," he said.

As regards atmospheric contamination, the crippled Fukushima plant radionuclides are known to have reached California and Mexico eight days after the disaster. Russia was unaffected by the propagation of radiation, says Maxim Shingarkin.

"The radioactive discharges to the atmosphere had failed to focus on either the Sea of Okhotsk, or Sakhalin Island, or the Far East, or the Kuril Islands. Besides, radiation transfer through the air has so far posed little or no danger. But let's wait and see, for not all fuel has been removed from the damaged nuclear reactors yet. We can therefore expect atmospheric radiation releases as a result of the heating up of reactors," he said.

It took years in the wake of the Chernobyl accident to draw more accurate conclusions about the scale of radioactive contamination. The situation around Fukushima seems to be pretty much the same, says Vladimir Slivyak, and elaborates.

"We are likely to learn about the detailed consequences of the Fukushima nuclear disaster in a matter of 10 to 15 years. It is clear that a great deal of fisheries, water grass areas and actually anything in the ocean has been contaminated. Fukushima radiation is understandably spreading across the world. It is obvious that large areas have been contaminated in Japan. But it will take years of research to get a more detailed picture of the Fukushima disaster consequences," he said.

Meanwhile, tests in California found that the blue-fin tuna caught in coastal waters were contaminated, according to the globalresearchreport.com portal. The contaminated water has most likely reached the area, since radioactive iodine levels have grown more than 200 times. 

The level of caesium-137 has also grown along the entire length of the US West Coast, the radioactive caesium was found in local berries and mushrooms. Meanwhile, local residents have reported more frequent bird deaths recently. Radionuclides have made it even to the Alaskan coast, causing a decline in the sockeye populations there. Some experts claim we are yet to see more consequences of the 2011 Fukushima nuclear power plant disaster.