Commonly comprised of dirt, pollen, skin cells, insects, pet dander, mold spores, bacteria, mycotoxins, dust mites, their refuse, and other such flotsam and jetsam, the buildup of indoor and outdoor ...

I spent the better part of my adult life on huge construction sites, where I was constantly breathing in the billowing dust of bulldozers and earth-movers, not to mention plumes of welding smoke. Like ...