John Polk wrote:
Azomite and glacial rock dust are each used as mineral amendments for soils that are deficient in minerals. Either one could be a waste of money if your soil has the minerals it needs. A complete soil test will show which minerals need replenishing. It would generally be cheaper to just apply the minerals that are needed, than applying an A to Z blanket containing most everything.
The mineral content of the two products are quite different. Look for the one that matches your needs the best:
Except that the main reason for adding such additives is to ensure trace mineral availability--something which, to my knowledge anyway--hasn't been determined for the vast majority (if any) plants.
Dealing with many naturally sourced minerals for this purpose, you will find mixtures far cheaper than concentrated pure compounds. And concentrating things is often a route to accidental overuse while presenting something of a safety hazard.
I suggest avoiding ingesting either of these additives--but due to particle size rather than any radiation danger. If you handle it in large amounts or frequently then wearing a particulate filter will protect you from both the dust (and any Alpha/Beta) by keeping it outside your body. Your skin stops both alpha and beta particles quite well. The amount gamma radiation is insignificant without ingestion and even if ingested, it would take quite a bit to raise your overall radiation level significantly. I suspect that the use rates for these additives would not provide enough increased radioactive material to make any increase in the plant's radioactive profile.
The radiation you ought to worry about is UV from the sun, which is far more likely to be injurous
