While most people are aware of outdoor pollution, they may know little about harmful air pollutants inside their home. That ignorance can have grave consequences.

Indoor pollutants can come from faulty combustion in appliances, trapped moisture, household products and home furnishings. Even the mattress we sleep on could, through a process called off-gassing, be a source of chemicals known as volatile organic compounds (VOC), making for much worse than a poor night’s sleep. The cumulative effects of exposure to indoor pollutants range from the sniffles to serious illness and death.

"Children are especially vulnerable to poor indoor air quality, due to their smaller and developing lungs," says Bernadette V. Upton, owner of EcoDecor Inc. in North Palm Beach, Florida. "A child’s lungs continue to develop until they’re 18 years old. That’s a long stretch of time for children to be exposed to toxic pollutants."

It’s one of many reasons why Upton became expert in green interiors. As a noted accredited professional with Leadership in Energy and Environmental Design and the American Society of Interior Designers, she’s in the forefront of her industry.

"When it comes to decorating our homes," she says, "we focus too much on how rooms look—such as the color of the walls and the pattern in the sofa (the visible)—forgetting to pay attention to what’s in products that can turn indoor air into a toxic soup (the invisible)."

Draw a Breath of Fresh Air

To begin, experts agree that every home and business should have proper ventilation to prevent the buildup of indoor pollutants. New buildings are made more airtight these days to keep out drafts and hold in warm or cool air, even though this puts occupants at risk for health problems.

To ensure that an adequate amount of outdoor air enters a home, open windows as often as possible during good weather. Also ask an HVAC (heating, ventilation and air conditioning) professional to see if the building could benefit from a mechanical system to remove pollutants. At a minimum, "Heating and cooling systems should have high-quality filters to capture fine particles and should be changed monthly," says Glenn Fellman, executive director of the Indoor Air Quality Association. But filters alone won’t solve serious air problems."If you’re concerned about your air quality, a portable high-efficiency particulate air (HEPA) room air cleaner in your main living area or bedroom may protect you further," says Fellman, "but the key is eliminating the contamination source."

Be Aware of Five Pollutants

1. CARBON MONOXIDE

Carbon monoxide (CO) is an odorless, colorless and tasteless toxic gas that’s produced when fossil fuels burn incompletely. At lower levels of exposure, CO causes flu-like symptoms. At high levels, it can cause unconsciousness and even death.Sources include natural gas stoves, cooktops, ovens, water heaters and furnaces, wood-burning stoves and fireplaces, kerosene space heaters, charcoal grills and gasoline motors. These sources present a danger to indoor air quality when the CO they produce leaks within a building, instead of being vented outdoors.

Prevention and Remediation

• Do not use kerosene and gas heaters without proper ventilation. • Use an exhaust fan vented to the outdoors when operating a gas stove. • Do not use a wood-burning fireplace if the smoke can be smelled indoors. It could be back-drafting and need inspecting. • Have a professional annually inspect combustion appliances for maintenance and cleanliness. • Never let a car sit idling in an attached garage or outside of open windows.

It helps to install a detector that will sound an alarm if unsafe levels of CO are detected. The Consumer Product Safety Commission recommends units that meet the requirements of the current UL standard 2034 or the IAS 6-96 standard. Detectors, however, are no substitute for the proper use and maintenance of CO-producing appliances.

2. RADON

Radon is a radioactive gas formed when naturally-occurring uranium decays in rock, soil and water. Odorless, colorless and tasteless, radon’s a proven carcinogen. The National Research Council estimates that indoor radon exposure is the second leading cause of lung cancer in the United States, responsible for 15,000 to 21,000 deaths each year.Radon enters homes from the ground through cracks and holes in the foundation, then works its way through gaps in walls and floors and around service pipes. The greatest exposure to this gas occurs in rooms that are below grade and in contact with the ground, but even second-story rooms can have elevated levels of this toxin.

Prevention and Remediation New structures can be built to resist radon infiltration.

• Build a sub-slab that creates a vacuum beneath the structure to hold soil gases, which are then piped outside. • Use mechanical barriers to stop the gas from entering the building. • Install an air exchange system that constantly replaces indoor air with fresh outdoor air.

Existing structures have a 1 in 15 chance of having elevated levels of radon, according to Environmental Protection Agency (EPA) estimates. A simple home test can reveal whether or not a building suffers from this problem. Discount testing kits are available from the National Safety Council online at www.NSC.org/issues/radon/

Radon levels that exceed 4 pCi/L (picocuries per liter) are considered hazardous and call for remediation by a professional. The National Environmental Health Association maintains a directory of qualified radon professionals at www.NEHA-nrpp.org  

3. MOLD

Molds, part of the fungus family, thrive in wet environments. They reproduce via tiny spores that become loose and float around in the air. Both mold-allergic and non-allergic people can experience hay fever-like symptoms when inhaling mold or mold spores. In some cases, molds produce potentially toxic substances called mycotoxins.

"Wherever you have moisture, eliminate it immediately," cautions Fellman. "Otherwise, there’s a real possibility of having a mold issue develop within 72 hours."

Prevention & Remediation

It helps to be diligent about finding and eliminating moisture problems. • Wipe water off surfaces within 24 to 48 hours. • Run bathroom exhaust fans, vented to the outside, during and following a shower, or open a window to help remove moisture quickly and completely. • Fix leaky roofs and plumbing. Water from such leaks is often trapped inside building cavities and cabinets, inhibiting evaporation. • Fix a leaky basement. Control roof water and surface drainage to divert water away from the foundation. • Maintain a relative humidity of 30 to 50 percent indoors, using a humidity meter (available at hardware stores). • Vent moisture-producing appliances to the outside (such as dryers and combustion appliances) and use dehumidifiers as necessary.

If you find mold, the EPA recommends using detergent and warm water to scrub it from nonporous, hard surfaces. Mold growing on porous materials, such as wood, ceiling tiles, upholstery and carpet, may be difficult or impossible to remove completely, and the contaminated section may have to be removed and replaced.

Avoid touching or inhaling any mold. The EPA recommends wearing an N-95 respirator (available at many hardware and paint stores), with goggles and gloves, during cleanup and reminds us that the job’s not complete until the water or moisture problem is fixed.

If the mold has spread to a large area or a difficult spot, such as inside ductwork, or if occupants suspect hidden mold, call in a professional mold specialist.  

4. VOLATILE ORGANIC COMPOUNDS

VOCs are a class of gases that can cause eye, skin, and respiratory tract irritation, dizziness, nausea and allergic reactions, as well as damage to the liver, kidneys and central nervous system. Some are suspected or known human carcinogens.

VOCs are present in thousands of consumer products, including household cleaners, air fresheners, aerosol sprays, pesticides, paints, wood stains and sealers, solvents, drycleaned garments and stain-resistant carpets.

Prevention and Remediation

• Look for low-and zero-VOC products, such as paints that carry the Green Seal label. Manufacturers say that these paints perform as well as conventional brands, while emitting far fewer toxic chemicals. • Use only as much of a household product as recommended by the manufacturer, and increase ventilation when using VOC-emitting products. • Store products far from living and work spaces. VOCs can escape from sealed containers.

5. FORMALDEHYDE

Formaldehyde, a type of VOC, is primarily used in the production of resins. Formaldehyde can be released into the air from materials by off-gassing. Unlike air pollutants like radon and CO, formaldehyde has a strong smell. Negative health effects include eye, nose and throat irritation, coughing, fatigue, rashes and allergic reactions. This toxin causes cancer in animals and may cause cancer in humans.Urea-formaldehyde (UF) and phenol-formaldehyde (PF) resins are used in pressed wood products such as particle board, plywood and fiberboard, often applied as sub-flooring and for shelving in cabinetry and furniture.

Other sources include adhesives, UF foam insulation, fiberglass insulation and permanent press textiles.Prevention and Remediation

• Purchase pressed wood products that meet or exceed the U.S. Department of Housing and Urban Development’s standard for formaldehyde emissions. • Look for a high percentage of laminated or coated surfaces and edges when buying cabinets and furniture. • Avoid foamed-in-place insulation containing formaldehyde. Choose blown-in, recycled cellulose, recycled cotton batting or formaldehyde-free fiberglass insulation instead. • Use exterior-grade pressed wood products containing PF resins, which emit formaldehyde at a lower rate than UF resins. • Avoid medium density fiberboard (MDF) in construction projects. It contains the highest resin-to-wood ratio of any UF-pressed wood product.When using PF- or UF-containing products, pick a solution that either slows formaldehyde release over time or accelerates its release prior to installation. • In humid conditions, dehumidifiers can slow down off-gassing. • Increase the flow of outdoor air indoors where these products are present. In new construction, ventilate the building with outside air for four weeks prior to occupancy. • Set pressed wood products out in the sun for up to four weeks before installing, in order to bake off gases. Allow for ventilation between each board.

Creating a healthy indoor environment can prevent many health problems and discomforts from sneaking up on us, making home the safe refuge it was always meant to be.

Resources: EPA Indoor Air Quality Information Clearinghouse: 800-438-4318. Indoor Air Quality Association: IAQA.org. National Safety Council: 800-SOS-RADON. National Environmental Health Association: www.NEHA-nrpp.org. Green Seal: www.GreenSeal.org.

Crissy Trask is a green lifestyle consultant and the author of It’s Easy Being Green: A Handbook for Earth-Friendly Living. She can be reached at [email protected]. Symptoms Related to Poor Indoor Air Quality• Headaches • Dizziness • Poor concentration • Fatigue • Nausea • Vomiting • Scratchy throat • Coughing • Running nose • Sneezing • Irritated, itchy eyes • Skin irritationSource: Environmental Protection Agency’s Office of Indoor Air Quality