DE are diatoms that have very very rigid cell walls. They can go into a dormant state when conditions are unfavorable. They have existed for a long time with this adaptation. But I can see where chickens really is saying they are sharp like glass. I haven’t researched what would happen to your lungs if you got them in it, but I’d guess it wouldn’t be good because or their rigid shape. In my mind it could be like getting fiberglass shards or asbestos in your lungs. And may tear up the mucus lining of the gut. But like I said I haven’t done the research. I’ve just worked with them in water/pond settings before. Not dried out where they are dust in the air.