By Russell McLendon
Indoor air pollutants are all around us, from radon and rodents to VOC's and NO2. Here are a few reasons why air-quality testing might help you breathe easier.
Air isn't as light as it seems. It's pushing on your skin right now with up to 15 pounds of pressure per square inch, a weight so familiar you can't feel it. Your lungs feel it, though, especially when it's bogged down with toxins. And while we tend to think of air pollution as an outdoor threat, it can be even worse inside the buildings where we live and work.
The causes of indoor air pollution vary from region to region, house to house and even room to room. Contaminated air seeps in from outside, but it also wafts up from a smorgasbord of indoor sources like construction materials, consumer products, mold, insects and pets. Poor ventilation can let it accumulate to dangerous levels, a problem that often spikes in fall and winter as we seal up buildings to conserve heat.
If you're concerned about the air inside your home or office — two places where many people do the bulk of their breathing — you might want to pick it apart with indoor air-quality testing. To help you clear the air once and for all, here's a look at some of the most common indoor air pollutants, how to detect them and how to deal with them.
4. Volatile organic compounds
Volatile organic compounds (VOCs) are in countless consumer products, from paint and glue to printers and shower curtains. They have low boiling points, causing them to "off-gas" lots of vapor even at room temperature. Some VOC vapors cause short-term health issues like headaches and nausea, often grouped together as "sick building syndrome." Others pose longer-term risks, from brain damage to cancer.
Average levels of certain VOCs are two to five times higher indoors than outdoors, according to the EPA, and they're prone to dramatic swings. During and for several hours after paint stripping, for example, indoor VOC levels can rise to 1,000 times the outdoor average. The best defense is to use VOC-containing products sparingly, and to keep their fumes from accumulating by using them outdoors or ventilating with fans and windows.
Testing for most VOCs isn't helpful, since no federal standards exist for non-industrial settings. A few VOCs warrant extra scrutiny, though, because of their links to cancer. One of the most infamous is formaldehyde, which wafts from pressed wood products, glues, textiles, gas stoves and tobacco smoke. The EPA suggests mitigation if indoor levels exceed 0.1 part per million. DIY test kits are available, but according to the University of Minnesota School of Public Health, "in cases where accuracy of results is important, only trained professionals should measure formaldehyde because of the difficulty of obtaining good data and interpreting results." Another carcinogenic VOC to avoid is benzene.
5. Mold and mildew
Fungi are notorious indoor air polluters, seizing on warm, humid conditions to colonize and contaminate. Outbreaks often begin in basements and bathrooms, but can quickly spread with enough moisture. Health effects vary by mold type and personal sensitivity; symptoms may include nasal stuffiness, wheezing and skin irritation. Studies have also linked indoor mold exposure to asthma development in children.
The best way to fight mold is to fight moisture. Keep the relative humidity indoors below 60 percent, and use a dehumidifier or fan to dry out the air if needed. Pockets of mold can be removed from hard surfaces by scrubbing with soap and water, a bleach solution or hydrogen peroxide, but check EPA guidelines for larger-scale cleanups.
Most molds cause human health problems, but our sensitivity varies and no federal standards exist, so air-quality testing is not usually advised as a first step. "You do not need to know the type of mold growing in your home, and CDC does not recommend or perform routine sampling for molds," the CDC says. "The best practice is to remove the mold and work to prevent future growth." Certain circumstances may call for more specific information, however, and most air-testing companies do offer mold inspection.
6. Dust, dander and droppings
Mold isn't the only biological polluter of indoor air. Many buildings are plagued by dust mites and cockroaches, two very different arthropods that both leave a trail of allergenic feces and body parts. Fumes from rodent urine and droppings can also cause breathing problems, as can pet dander and airborne proteins from cat saliva. On top of that, indoor air may be invaded by pollen and bacteria from outside.
These contaminants often trigger allergic reactions and asthma, and symptoms can grow worse with chronic exposure. Children, elderly people and people with other breathing issues are especially at risk from biological agents in confined areas, the EPA warns.
Testing can sniff out some biological pollutants, but as with mold, it may be easier to use visual clues. Regular sightings of roaches, rats or their droppings point to an infestation, in which case pest control is likely the best way to clear the air. Dust mites aren't visible to the naked eye, but we can see piles of their namesake food — and cleaning up dust may also alleviate allergies from pet dander. Beyond good housekeeping, ventilation can help keep unavoidable allergens from reaching high concentrations.