Real Salt users like knowing that our product comes from an ancient sea bed, because we can all see the value of eating sea salt from a deposit left long before humans were around to pollute the water with chemicals and gushing oil. But every now and again, we hear from a customer wondering whether the Real Salt deposit was protected from a very different kind of pollution: radiation from nuclear tests in Nevada 60 years ago.
In the 1950’s, the United States government carried out a series of nuclear weapons tests in the Nevada desert. A generation of residents exposed to the fallout experienced serious health problems, so it makes sense to wonder how the tests may have affected natural resources in the West. We care about our health (and we put Real Salt on just about everything we eat) so we asked these same questions ourselves. Here’s what we learned.
When dealing with protection from the effects of radiation, experts talk about three factors: distance, shielding, and time.
Distance
Because of wind and weather patterns, two counties in Utah absorbed high levels of radiation. The Real Salt deposit is more than 125 miles north of either of these counties and about 300 miles from the Nevada testing site. The inverse square law applies to radiation exposure, so doubling the distance decreased the intensity by a factor of four. In other words, if the ground above the Real Salt deposit absorbed radiation, it would have been less than half the amount required for the National Cancer Institute to consider it high.
Shielding
Did we just say the ground above our deposit may have been affected by radiation 60 years ago? Well, yes, nobody can be certain one way or the other, but here’s why that shouldn’t trouble you.
Experts have learned that 3.6 inches of compact earth cuts incoming gamma radiation in half, which means that three feet of earth reduces the possible exposure to 1/64 its original strength. (Most earthen fallout shelters are beneath three feet of dirt.) Real Salt comes from a mineral deposit 300 feet below the surface of the earth, which means that if radiation found its way to our deposit site it would have met with 300 feet of protection before it could contaminate the minerals.
Time
Scientists have found that gamma radiation decays at a constant rate called the seven-ten rule: For every seven times older the fallout becomes, it retains only 10% of its original strength. This means that 90% of radiation is gone after seven hours, and the remaining 10% is almost completely gone two days later. Since these tests ended fifty years ago, there is clearly no current risk of contamination.
Real Salt and Radiation
The distance between the Nevada test site and our deposit would have limited the strength of any possible fallout, and 300 feet of earth would have weakened any remaining radiation to an immeasurable amount long before it could have reached the salt. That sounds pretty good in theory, but since we are naturally curious people we still asked a lab to analyze some samples. The results? They actually did detect a small amount of radiation, which made us furrow our brow a bit until the technician told us that a person would need to eat about eight pounds of straight Real Salt to get the amount of radiation they’d find in a single quart of clean drinking water. In other words, we may live on a radiation-heavy planet, but Real Salt isn’t the least bit harmful.