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Radioactive Turkeys? Serving Hot Food this Thanksgiving
Posted on November 26th, 2013

The Earth is hot

Did you know that the earth maintains a warm climate in large part because of the radioactive decay of uranium and thorium contained within the earth's core?  In fact, scientists have estimated that about 50% of the radiant heat that escapes the earth is from this radioactivity.  

The radiation emitted by these naturally occurring radioactive elements results in heat when the emitted radiations are stopped within the earth.  Given the size of the earth much of this heat is trapped within and helps keep us warm.  If it were not for this radioactive decay, our earth would cool to a nearly uninhabitable climate despite the proximity to the sun.  

Our bodies are hot

Radioactivity enters our bodies through several ways, including the air we breathe and the foods we eat.  Some of this radioactivity is natural, like uranium, thorium and potassium-40, and some is man-made, like cesium-137 and strontium-90.  Regardless of the source, most of this radioactivity is ubiquitous and only some can be controlled by our diets and lifestyle.  The radiation dose we receive from natural background radioactivity is low and harmless.  The portion that comes from dietary choices is very low, and presents no risk to our health.  Your body always contains some natural radioactivity in the form of potassium-40.  In fact, if you routinely sleep next to another person for 8 hours, the dose from this partner is estimated to be 2 mrem per year.   

Where cesium-137 and strontium-90 comes from  

Both of these radioactive elements are fission products and are byproducts of the nuclear fission process (the splitting of uranium or plutonium atoms).  There are many other radioactive elements that are created during fission but, cesium-137 and strontium-90 are very common AND they both decay very slowly with half lives of about 30 years.  These radioactive elements have entered our environment from several time periods and “events”.  The first events were the above ground tests of nuclear weapons.  This testing started in 1945 in the US and continued through 1980, with China performing the most recent tests.  Another event was the use of nuclear weapons against Japan in WWII.  Other sources of these fission products in our atmosphere were from some of the nuclear power plant accidents throughout the world including the more recent events of Chernobyl (1986) and Fukushima (2010).  All of these events added to the world environmental inventory of cesium-137 and strontium-90.  

How cesium-137 and strontium-90 gets into our food  

Both of these radioactive elements behave exactly the same as their non-radioactive counterparts.  Cesium is chemically similar to potassium and sodium, where as strontium is chemically similar to calcium and magnesium.  Plants that have a tendency to concentrate these non-radioactive elements as part of their life cycle will also concentrate equivalent amounts of cesium-137 and strontium-90, along with naturally occurring potassium-40 that may be in the surrounding soils naturally, or from fallout of cesium-137 and strontium-90 from the atmosphere.  Absorption rates can vary widely and depend on many factors such as the species of plant, the amount of fallout present, seasonal temperatures, rainfall and other environmental conditions.   In areas where plant absorption is higher, the amount of radioactivity that enters the human food supply can be elevated.  When livestock or game animals consume plant products which have absorbed more of these radioactive elements, the resulting meat will contain, and often concentrate, these elements. 

Radioactive turkeys  

Some wild game animals, such as wild turkeys, deer, and moose, enjoy a diet high in berries and nuts.  This vegetation has a tendency to concentrate cesium and strontium at a higher rate than grain producing plants.  Therefore, if you are eating a wild animal for Thanksgiving, you will probably be consuming a little extra radioactivity.  If you also have some cranberry sauce, you will get a bit more.  If you have a farm-raised commercial turkey, it was most likely raised on grains that absorb less cesium and strontium,  so you will ingest less of these radioactive elements and will get less dose compared to a game-based meal.  In any event, your Thanksgiving Day meal will include some radioactivity - just like every other meal you eat!

How I know this  

In my prior career, I managed a dosimetry laboratory that processed Thermo-Luminescent-Dosimeters (TLDs) to monitor workers for external radiation dose.  We also monitored workers for any potential internal radioactivity using sophisticated gamma spectroscopy detection systems. Several times a year, the analysis of some workers showed the presence of cesium-137 from inside the body.  Often times, these workers had almost no chance of receiving this intake from their jobs.  In these cases, one of our first questions was, "Do you eat game meat?"  Almost every time, the answer was yes, and the case was closed.

What will happen if you eat radioactive turkey   

There you are with your overstuffed belly along with some internal warmth and the feeling of a nice nap.  Is that heat from the decay of the radioactivity you just ate, just like the internal heat of the earth?  Not likely.  The amount of energy emitted by the small amounts of radioactivity you just ate would only increase your core temperature by a few micro-degrees.  My guess is that you just ate too much and your internal engine is busy burning these calories and giving off heat.

Happy Thanksgiving and have a nice nap!

I hope you found this entertaining and educational, 

Eric Darois, MS.c, CHP 


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