Originally Posted by servatusprime
So is the theory that the this stuff will make its way into the fruit and create some health concerns? Would a safer alternative with similar benefits be greensand? (other readily available suggestions?)
Greensand is a way for rock quarries to sell crusher dust instead of paying for its disposal elsewhere. It does contain a lot of minerals, but they are in covalent form and unavailable to plants.
On the other hand, it is beneficial to have sand and rock dust as a component of a garden soil -- along with a modest percentage of humic material. The sands and rock dust will provide important catalytic action for exchanges of ionic compounds.
There is no panacea in gardening, in human health, etc. If you are looking for a "silver bullet" -- go load up a shotgun and shoot all your plants. It will save you a lot of money and effort.