I keep all that stuff in a jar. When it is full, I throw it in the trash. There used to be a slit in the back of my medicine cabinet where you could dispose of used razor blades so they went down inside the wall. I had the cabinet removed a long time ago and the drywall redone but I used to put needles, etc. in there. I don't remember if the opening would have been big enough for a rotary blade.