Bananas More Radioactive Than Fukushima Tuna
Last spring, a certain study was released, and the media headlines blared, over 1,100 in all. They all went a little something like this:
Most of the stories delivered alarmism, but relayed little context. All most readers learned was that Pacific bluefin tuna -- fish that many Americans consume -- were tainted with radioactive cesium from the Fukushima-Daiichi nuclear accident. Sounds scary, doesn't it?
But there's almost no need to worry, say Nicholas Fisher and Zosia Baumann, the same researchers who conducted the original study. In a new study which appeared Monday in the Proceedings of the National Academy of Sciences, they demonstrate that the effective radiation dose received by humans based on the annual consumption of contaminated Pacific bluefin tuna is comparable to, or less than, the dose routinely obtained from "many food items, medical treatments, air travel, or other background sources."
For example, say you're at a fancy restaurant and you sit down to an exquisite meal of Fukushima-tainted Pacific bluefin tuna. Your radiation dose would be approximately 7.7 nanosieverts. That's about 5% of the dose acquired from the Potassium in an uncontaminated store-bought banana.
Even a hypothetical subsistence fisherman living in the United States consuming 273 pounds of bluefin tuna annually (more than five times typical American consumption of seafood) shouldn't lose much sleep. The research team calculated that such a demographic would suffer an additional two cases of fatal cancer per 10,000,000 people.
The research team used measurements of radioactive cesium taken from Pacific bluefin tuna caught in 2011 near San Diego, California for their calculations. They also caught specimens in 2012 and found that cesium levels had significantly diminished to less than half of those found the previous year. Thus, the almost nonexistent radiation risk faced by Americans may be even more diminutive.
Source: Nicholas S. Fisher, Karine Beaugelin-Seiller, Thomas G. Hinton, Zofia Baumann, Daniel J. Madigan, and Jacqueline Garnier-Laplace. Evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood. doi: 10.1073/pnas.1221834110 PNAS June 3, 2013