Indoor Air Pollution (IAQ) is often overlooked as a harmful part of air pollution but it should be addressed instead of skirted under the table. It can come from air conditioners or heaters, like the exhaust or the freon. It can come by way of cigarette or cigar smoke too. Aerosol can sprays, like air freshners and deoderants, are very harmful to people and come from inside the home often times.
Even plug in air freshners, candles that contain toxic ingredients, perfume and things you wouldn't think were harmful can be bad. Household cleaners, laundry spot removing sprays, and many other things we think are killing the very air we breath inside our own homes. We think of pollution as being all outside but it certainly isn't.