Before I learned this important info, I had brought a bunch of different dusts too. I took a class several years ago where the instructor discussed this at length. After that, I sidelined any that I had that did not specially say FDA approved food color. I had purchased the other for gumpaste flowers only anyway. At this point I will only buy ones that are approved. While they are NON-TOXIC I would just rather err on the side of caution.
If it doesn't say that it is approved I would be suspious that it is not. If I am not sure, I have e-mailed companies and asked before I purchased.
I don't run a business, it is a hobby for me.
I do think the FDA might be being a little over zealous, but for me, I try to stick to the rules. Hopefully, they will lighten up in the future.