Indoor Air Pollution

What's the most polluted atmosphere to which most of us are exposed? One clue—it's not the outdoor air that we've spent zillions of dollars to clean up. The answer? It's the air in our homes and offices. Enormous attention has been paid to outdoor pollution and it's impact on health, but people spend up to 90 percent of their time inside, making indoor air quality extremely important. 

Many people perceive that the risk from outdoor air is substantially higher than indoor air. In fact, the home environment is rarely considered to be a risk in this regard. In terms of regulation and control, the principal sources of pollution, such as vehicles and factories, lend themselves to formal legislative control. By contrast, exposure in the home is very much dominated by personal choice and behavior. 

Scientists have shown that the levels of many substances, such as volatile and semi-volatile organic compounds, are substantially higher indoors than outdoors. Indoor emissions come from many sources, such as stoves, smoking, cleaning products, home furnishings and even people. These chemicals can react with others to form new molecules. Sunlight from windows and emissions from gas stoves often accelerate these reactions. Houses also contain many surfaces including windows, carpets, walls and furniture that can absorb react and re-emit compounds. And people themselves emit volatile organic compounds from their breath, skin and personal care products.¹