American
scientists found minuscule levels of radioactive cesium-134 and
cesium-137 in bluefin tuna caught off San Diego, California last August.
The
researchers – who hail from Stanford University, Stony Brook
University, and Yale University – say there’s no doubt that the cesium
radionuclides they found come from the Japanese nuclear reactors damaged
by the March 2011 tsunami (Madigan DJ et al. 2012).
Tissue
samples were taken from 15 bluefin tuna caught by recreational anglers
five months after the meltdowns at Fukushima Daiichi.
The
samples from all 15 tuna contained the reactor byproducts cesium-134
and cesium-137 … but in amounts very far below those considered unsafe,
the scientists said.
The results were just published online in the Proceedings of the National Academy of Sciences.
We
tested our Pacific seafood last March, and it passed with flying colors
… see our sidebar, “Vital Choice Pacific seafood tested very safe”.
Levels detected fall far below natural background radiation
It’s important to put the levels detected in California-caught bluefin tuna into perspective.
The
amounts of radiation produced by the cesium the scientists found are
only about three percent higher than those produced by natural
background sources of cesium-134 and cesium-137.
Further,
the levels of both isotopes are just one-thirtieth the amount of
naturally occurring radioactive potassium found in all marine life, and
only about 2.5 percent of the limits Japan imposed on fish caught after
the accident.
As
the authors wrote, “even though 2011 PBFT showed a 10-fold increase in
radiocesium concentrations, 134Cs and 137Cs would still likely provide
low doses of radioactivity relative to naturally occurring
radionuclides, particularly 210Po and 40K” (Madigan DJ et al. 2012).
Specifically,
the concentrations of both isotopes of cesium totaled about 10
becquerels per kilogram (kg) of dry weight. (A becquerel is a unit of
radioactivity equal to one nuclear disintegration per second.)
For comparison, these are the total Bq values of various foods and objects under normal circumstances (WNA 2012):
Bananas = 19 Bq/kg
Coffee = 1000 Bq/kg
Brazil nuts = 444 Bq/kg
Adult human = 7000 Bq/kg
Granite countertop = 1000 Bq/kg
EPA maximum for drinking water = 740 Bq (tritium/liter)
Household smoke detector (with Americium) = 30,000 Bq/kg
The
major natural source of radioactivity in plant foods is Potassium-40,
which normally constitutes just 0.0117% of the potassium in a plant
food.
A
typical banana contains about half a gram of potassium, and the portion
that occurs as Potassium 40 gives bananas a radiation level of 15-20
Bq/kg.
Visit Vital Choice Seafood for one of the safest and highest quality seafood available.