How Sick Is Your Home?

Indoor air pollution -- from mold to radon -- presents health risks

Nobody wants environmental hazards such as toxic-waste dumps or smokestacks bellowing gritty plumes in their backyards. But the same sorts of pollutants that come from these sites could be lurking right in your home. Indeed, it can be teeming with allergens, such as dust mites. Carbon monoxide can escape from fireplaces, mold and bacteria often funnel through muck-filled heating, ventilation, and cooling systems, and volatile organic chemicals seep out of paint and carpets. Scientists have also found that even innocuous household products, such as air fresheners, can become dangerous when their fumes react with ozone and create carcinogens, such as formaldehyde. It's little wonder the Environmental Protection Agency (EPA) has deemed indoor air quality one of the top five environmental health risks the U.S. faces today. The agency says indoor levels of pollutants can be two to five times -- and sometimes more than 100 times -- as high as outdoor levels. "Just because outdoor air is cleaner doesn't ensure that indoor air is cleaner," says William Nazaroff, professor of environmental engineering at the University of California at Berkeley.

You can trace some of the problems of indoor home pollution to a noble effort -- energy efficiency. "We're building tighter and tighter homes and bringing all sorts of products and chemicals into them, but there's less and less air going through," says Richard Corsi, director at the Texas Institute for the Indoor Environment at the University of Texas in Austin. "A tighter home is good from the standpoint of conserving energy but bad in terms of occupants inside."

That's why some builders are beginning to take steps to put up houses that are both energy-efficient and healthy. Indeed, as concern has risen over indoor pollution, initiatives such as Austin Energy Green Building Program and the American Lung Assn.'s Health House Program, which credit builders for addressing such issues, have taken off, say program execs. Health House homes cost 3% to 5% more to construct, but they're 30% to 40% more energy efficient.

In addition, builders such as WCI Communities in Bonita Springs, Fla., are beginning to make a strategy out of building healthier homes. WCI, the largest builder in humidity-laden Florida, recently began offering "green" houses that include both energy-saving and healthful features. So far, they've sold 224 units in their Venetian Golf & River Club in Venice, Fla., with an average price of $360,000.

Those features include a high-efficiency particulate air (HEPA) filtering system that removes 99.97% of airborne particles. The air-conditioning has ultraviolet lights in the ducts so that circulated air is treated to kill mold and mildew. The homes also have wool carpeting and floorings made of bamboo or cork as alternatives to traditional carpeting made from synthetics, which gives off noxious gases. "If you are going to use a carpet, go with a natural carpet like wool," says Jennifer Languell, director of the WCI Green Building project at Florida Gulf Coast University in Fort Myers who helped design WCI's model green home. "The better option is to use area rugs that you can take outside the house and clean."


Experts say new concerns are cropping up every day that could be potential health hazards, including the combination of certain chemicals and the continuing presence of some chemicals in homes years after they have been banned. For example, Corsi, whose University of Texas team has conducted studies on air pollutants, says ozone -- the key component in smog -- is emerging as an indoor problem. Alone, levels of ozone tend to be lower inside than outside. But so-called oily terpenes from products such as air fresheners, aroma-therapy candles and oils, and cleaning agents can react rapidly with ozone in indoor air to generate secondary pollutants like formaldehyde, a known carcinogen.

Meanwhile, a study released last fall -- led by Ruthann Rudel, a scientist at the nonprofit Silent Spring Institute in Newton, Mass., and John Spengler, professor of environmental health at Harvard University's School of Public Health -- found long-banned toxic substances such as PCBs and DDT among the contaminants in 120 houses on Cape Cod. The four-year study tested the houses for 89 organic chemicals identified as endocrine-disrupting compounds. EDCs are chemicals that can interfere with human hormones and have been linked to increased rates of testicular and breast cancer, as well as certain birth defects and neurological problems. "One of the things that surprised us was evidence of a pesticide like DDT, which has been banned for more than 30 years, and residuals of a flame-retardant that has been banned for about 20 years," says Spengler, who is also author of the Indoor Air Quality Handbook. "Some of these chemicals don't break down easily and can survive a long time in the home."


Cleaning up your indoor air can be simple or complicated, depending on the problem. Mold requires moisture in order to propagate, so eliminating the source of the wetness -- say, a leaky roof or damp crawl spaces -- is critical. If you smell mold but can't see it, you can try a moisture meter, whose price may start at around $75. Or call in a professional, for whom the cost will probably range upward from between $150 and $200 -- depending on how many samples are needed. A lab will analyze samples, and if they're not hazardous, you can usually just clean up the mold and disinfect it with household bleach. If the samples are toxic, then call a pro.

While mold announces its presence, carbon monoxide (CO) and radon do not. Your best bet for CO is a carbon monoxide detector, which sells in home-improvement and other retail stores for as little as $25 to $50. Experts say you should have them installed throughout the house, including in rooms where the fireplace or furnace are located and in or near bedrooms and basements.

Things could get a bit more complicated with radon. The EPA says that radon -- a colorless, odorless, tasteless gas that occurs naturally in the soil and rocks -- is second only to cigarette smoke as a cause of lung cancer. The EPA recommends that all houses be regularly checked for radon, because elevated levels of the toxic substance have been found in every state, with an estimated one out of every 15 homes in the country having indoor radon levels at or above the EPA's recommended action guideline of four picocuries per liter of air (pCi/L). "To the homeowner, they just look like cracks in the floor or foundation, but to radon molecules those are the Grand Canyon," says inspector Lon Grossman of Technihouse Inspections in Bloomfield Hills, Mich.

Testing for radon is simple and inexpensive if you do it yourself. You can buy test kits through the mail or at hardware stores, health departments, or other retail outlets. Or you can hire a so-called radon-mitigation professional. But when looking for a kit or a pro, make sure you choose one that is certified by either the National Environmental Health Assn. or the National Radon Safety Board, experts say. Grossman, who is certified, says to get accurate results, run the test at the lowest living area in the house and with the windows closed. If radon levels are above four pCi/L, you can try fixing the problem yourself by sealing cracks in floors and walls and doing another test. If it's still high, call in a professional.

Sure, it's unsettling to think about the pollutants that can invade your home. But you can rest easier knowing there are ways to get rid of them.

By Stephanie Anderson Forest

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