I recently was cleaning a shed out at my school, and there were 4 bags of Snow White that the bottoms had rotted out of. Not thinking we just got a broom and shovel and removed it but the powder (Snow White) then became airborn. After that I was having trouble breathing so I left and took a bag with me and read the label, it said the following: this product contains small amounts of crystalline sylica and non esbestes tremolite which may cause cancer and or other serious lung conditions. We where in the shed with 1 door of it open (very small shed and door) for about 5 minutes. Should I be concerned about what we breathed in? Did we have enough time to be exposed to dangerous levels of it? Thanks