Indoor Pollution—our worse enemy

Some of the most polluted air you can breathe isn't downtown but inside your own home. Surprised? Studies from the Environmental Protection Agency show typical airborne pollutants now run two to five times higher indoors than out, especially now that auto emissions and industrial smoke have been curbed. Blame it on household chemicals and appliance vapors, along with molds accumulating inside tightly sealed houses. We already spend 90% of our time indoors, and approaching winter weather augurs months of more confinement. But with good awareness of the source of indoor pollutants and proper maintenance we can clear the air and live a healthier life.

In the past, toxic offices became known as the prime cause of many diseases—Legionnaire’s Disease being the classical case. The sick building syndrome comes from hermetically sealed highrises with dirty air-conditioning systems or noxious building materials, sickening employees. Now, the home is drawing attention as a zone of concentrated chemical vapors, fuels, appliance byproducts and biological detritus from pets or pests. Hazards vary from house to house, but high levels of chemicals can exacerbate respiratory illness like asthma, and increase the risk of cancer or other chronic disease. This is particularly important for people who have over reactive immune systems—people you often see sneezing. Allergic symptoms therefore abound in many homes not well maintained to remove these pollutants. Combustion byproducts from heaters and stoves, for example, include particulates and nitrogen oxides. Poorly vented fireplaces or kerosene heaters give off carcinogens known as PAHs (polycyclic aromatic hydrocarbons). Gas stoves emit nitrogen oxides that inflame the lungs and trigger asthma. (Households with asthma sufferers might even consider switching from a gas to an electric range.)

Malfunctioning heaters can leak deadly carbon monoxide, as do cars or lawnmowers running inside an attached garage. Make sure gases are vented outdoors. Wood-burning stoves should have proper vents, and can be equipped with catalytic converters. Secondhand cigarette smoke exposes you to high levels of nitrogen oxides, particulates and volatile organic compounds such as benzene and toluene, all carcinogenic.

Highly allergenic mold and mildew spores, visible as a black residue on walls and windows are hazardous; humidity also nurtures bacteria that emit airborne toxins. Mold and bacterial toxins cause lung disease when airborne. Bleach kills both, and dehumidifiers can dry up the moisture they need to grow. Dust mites also thrive in high humidity, inflaming lungs of asthma sufferers.

Formaldehyde, a staple ingredient in paints and plywood, is an animal carcinogen and possible human carcinogen. Using such products calls for extra ventilation. If possible, consider alternative furniture materials. If you must use compressed wood, seal raw wood edges, and choose "exterior-grade plywood," which releases less chemical gas than the interior grade.

Limit your exposure to mothballs and long-acting deodorizers containing paradicholorbenzene, an animal carcinogen with unknown long-term human effects. It is better to seal them in trunks and store in a detached garage or ventilated attic. A benign alternative: cedar chips.

Wall-to-wall carpet can be a hot zone of both chemical and natural toxins. Carpet adhesives and backing can contain chemicals such as styrene, a suspected carcinogen, and 4-PC, the source of pungent "new-carpet" odor. The effects of long-term exposure are unknown. Consider wood floors and area rugs that can be removed and cleaned. If you're installing carpet, ask workers to unroll and air it out before laying it down. Old carpet, a reservoir for dust, pet dander and mold, should be replaced.

Dry cleaning uses the solvent perchloroethylene, an animal carcinogen that can linger inside plastic bags. Air out freshly dry cleaned clothes before bringing them into the house. Reject items with overpowering chemical smell, and ask your cleaner to extract the chemical and dry clothing properly. Safer fabric-cleaning technologies now under development include liquid carbon dioxide and water-based processes.

Avoid releasing clouds of aerosols, cleaners, solvents, paint strippers and hobby chemicals when your house is shuttered for the winter. Choose trigger sprays over aerosols.

Try to occasionally open windows and doors to invite a gust of fresh air. The use of electronic air cleaners is debatable. They can purge airborne irritants but leave behind chemicals and allergens imbedded in drapes or carpets. Remember to clean filters; dirty ones can compound the problem, in your vacuum cleaners also.

Shakespeare once said that the fault lies in ourselves and not our stars—the bigger problem lies not in outdoors but indoors mainly because we spend so much time there; unfortunately, we pay little attention to it assuming our work place and home environment to be safe. It is anything but.