Part of why this is hard to pin down is that household dust isn’t any one specific thing. It’s just a disgusting salad made from whatever happens to be lying around your house. It can include soil, pollen, cotton fibers, crumbs, powdered sugar, glitter, pet hair and dander, plastic, soot, human or animal hair, flour, glass, smoke, mites, and countless blobs of hard-to-identify gunk stuck together.
