A Tip for Brazil Nut Farmers

A friend of mine posted a note about Brazil nuts being unusually high in radioactivity. So I investigated the situation and came up with this "solution" to the problem.

It appears that the uptake of the element radium by the root system of the plant results from the need for the element barium as a micronutrient. Radium occurs at a typical concentration of one part per trillion in the soil (one million out of one million) and the radium is concentrated by the root system because there is a lack of barium in the soil.

Radium in the soil is the natural result of the radioactive decay of uranium.

If the farmers of Brazil nuts would introduce barium into the soil in small amounts, most likely through irrigation, the plant would preferentially pick up barium, and the radioactive "problem" would greatly diminish. I am not sure what concentration of barium would be appropriate, but if the barium were at a concentration of one part per million in the soil, it would be on the order of a million times greater than the radium. They would just need to eXperiment with this idea to see if it is practical and actually works. I think that barium compounds are relatively cheap and most are relatively insoluble in water.

I believe this barium increase idea follows the chemical reaction rule called "Le Chatelier's Principle", although there may be a better rule that accurately describes it.

Link to Wikipedia article: Le Chatelier's Principle