I know what you mean about spending so much money on supplements. I probably have spent enough, on supplements and health gizmos, to buy a house over the last 40 years.
DE is a very fine powder. Very fine. You could not see any sharp edges without a microscope. Even when I add a tablespoon to water, it sends out little poofs of dust (I can see in the sunlight). I just take a breath and don't breathe for a few seconds. It should not be an irritant unless you breathe it frequently. It is an irritant for those who mine for it. It is inorganic and benign.
I can tell that it is eliminating parasites due to my much, much better bowel movements. Also, my symptoms of die-off for which I am very familiar. My favorite parasite cleanse is with Humaworm. It has been a year since I did that. I eat a lot of raw veggies; so no wonder that I have parasites. Also, I had and overgrowth of fungus. That is so difficult to get rid of. It just keeps coming back. Even after I took Miracle-Mineral-Supplement for 9 months.