if you fill the walls with straw and newspaper and patch up holes with cardboard boxes and wallpaper,
dust.
if you cram old insulation up against a damp basement ceiling secured with cardboard and stuffed with rags,
mold.
if your main drain is rusty and drains through a hole in the floor,
sewer backup.
if you bury plastic bags of mulch half a foot under the soil and plant vegetables on top,
poison.
it's one way of living.