Wondering if you can still eat that toro tuna after the nuclear disaster in Japan? Here are 5 things you need to know and the nuclear disaster of Fukushima and seafood:
The Fukushima Daiichi nuclear disaster followed the March 11th 2011 Tōhoku earthquake and tsunami in Japan, and was on the same level as (or some say worse than) the Chernobyl disaster of 1986. More than two years later, it has been revealed that the nuclear reactor is still leaking radioactivity into the seawater (300 tons of radioactive seawater every day), something that experts and fishermen long suspected.
2- Radioactivity has been detected in foods such as milk
Radioactivity has been detected in milk on the west coast of the United States, namely in Washington state. How did it get there? When radioactivity gets into the atmosphere, it eventually makes its way down to the ground and contaminates the environment. No need to panic just yet, since the levels are reportedly 5000 times below safe levels for adults and children. The Environmental Protection Agency (EPA) is taking extra steps for testing, though.
3- Seafood could be contaminated
Following the Fukushima nuclear disaster, scientists in both the US and Japan monitored Pacific fish for radiation. In 2011 and 2012, radioactive isotopes were found in the seawater and 40% of bottom-dwelling fish were found to have unsafe levels of cesium-134 and 137 (by japanese standards).
And in August of 2013, they found what we all feared: a “murasoi” fish (similar to a rockfish) was found to have 2500 times the safe levels of radioactivity. This particular fish was caught in the vicinity of the nuclear power plant. What does this mean for other countries, like the US?
It appears that, for now, the major concern is for bottom-dwelling fish in the immediate vicinity of the Fukushima disaster. This means that highly migratory fish, like tuna, which can swim across the ocean and would have to go through thousands of miles of uncontaminated waters to get to US shores, would not be a great concern. Dr. Ken Buessler of the Woods Hole Oceanographic Institute says that although there would be a concern if radioactivity were to move up the food chain from small fish to big ones (through a process known as bioaccumulation), levels aren’t high enough to merit any concern for the moment.
4- We consume radioactivity every day
Not to downplay the danger, but we regularly eat foods that (like most organic materials) naturally contain radioactive isotopes due to their high content of potassium (of which some is always radioactive). Examples of these are macadamia nuts and bananas. In fact, there is a Banana Equivalent Dose which compares the amount of radioactivity of a particular exposure to its equivalent in bananas. One estimate has Fukushima leak equivalent to 76 million bananas, which sounds like a lot until you read that 1.45 trillion bananas are eaten every year around the world.
The EPA isn’t convinced that BEDs are a valid measuring tool, however, since the amount of potassium in our bodies is fairly constant thanks to homeostasis. Any radiation ingested in bananas would last only a few hours after consumption, the amount of time that it takes for our kidneys to restore our natural potassium levels. (See page 16 of this report).
5- Dilution is the solution to pollution?
For now, any seafood caught outside the 100-mile radius of the Fukushima nuclear disaster is considered safe, according to Stony Brook University scientist Nicolas Fisher. Even if radioactive water were to be carried out by currents, natural mixing with uncontaminated water would lead to considerable dilution. Does this comfort consumers? Not really. Until the reactors are completely sealed, which is a plan in the works now using ice, the problem will only get worse.