Some parrots can see ultraviolet.

Dust is not mostly made of human skin particles in fact these make up only a small percentage of common household dust, other factors make up the bulk such as clothing fibres, lint, insects (corpses of dust mites and dried feaces of the same) and if you have animals - animal hair/skin.
Other componant can depend on the environment concrete dust in basments, pollen particles if you have a lot of flowers.