Most people have no idea that they aren"t breathing in only oxygen when they inhale. Outdoors, they may be inhaling volatile organic compounds (VOCs) from automobile exhaust, benzene, solvents, PCBs, MTBE, wood smoke, dust particulates, soot, and ozone. Indoors, they may be inhaling formaldehyde, radon, radiation, or asbestos fibrils. Without even knowing it, they may be suffering from sick-building syndrome. This book is important reading for everyone who wants to know how air quality relates to health and how it can be improved in their personal environments.