It's pretty obvious you're trying to imply that it's harmful in some way, but I checked wikipedia and I can't see anything bad about it aside from the generic "eww chemicals" feeling. Sure, technically speaking I wouldn't sprinkle that on my salad either, but that encompasses a wide variety of substances that aren't exactly bad for you. I wouldn't sprinkle sodium bicarbonate (baking soda) on my salad either, but it's not exactly bad for me.