I was a school cook for over 18 years only after the federal govement told us we had to use 50% wheat flour in our baking did I get sick. The flour was bug infested, moldy and when you mixed it up dust flew every where. I started havving upper resper. infections and sinus problems. Droctors seem to forget that flour dust is the same as any other dust it can do harm also.I had my ear nose and throat dr tell me if I gor to the Mayo clinic I will get told what I want to be told.