Aug. 25, 2012 -- Formaldehyde. Radioactive chemicals. Bug droppings. You wouldn't dare eat food laced with this stuff—heck, you'd probably alert the health department. And yet you may be sucking down these toxins, and a flurry of others, with every breath.
"Most people aren't aware of the dangers of the air they breathe. The contaminants are often invisible, and the harmful effects may not be dramatic at first," says Anne Steinemann, Ph.D., a civil and environmental engineer at the University of Washington. "But exposures add up over time, and so does the damage."
In fact, a growing body of research suggests that airborne contaminants may impair your memory, weaken your sperm, and raise your risk of heart disease and cancer. (They're not the only thing you need to watch out for.
To keep your body healthy, avoid America's Most Dangerous Workout Fads.) Worse, your body has no internal smoke alarm to signal danger. So we've identified the biggest airborne enemies and outlined strategies to help you protect your lungs—and your life.
You're not the only one making babies in bed: Dust mites may be multiplying by the millions in your mattress and pillow.
If you're allergic to them and their droppings (often found in dust) a noseful can trigger sneezing and watery eyes, says allergist James Sublett, M.D Allergic or not, there's a greater danger: In a University of Cincinnati study, mice that regularly inhaled dust mite debris had narrowed arteries in their lungs, a condition that can lead to heart failure.
To beat the bugs for good, you need to launch an all-out offensive. A recent study in Environmental Health Perspectives found that using mite-proof mattress cases, washing bed linens weekly in hot water, and intensively vacuuming and dry steam cleaning carpets and upholstery all helped slash dust mite counts by up to 95 percent.
That takes care of the critters. Now tackle their feces and body fragments floating around the room: For an hour a day, run an air purifier with a prefilter and an electrostatic filter, such as the Ken-more Electrostatic Air Cleaner ($300, amazon.com). This can significantly lower levels of airborne mite particles, say Korean scientists.
You check your bread for mold, but how about your air? Aspergillus and Penicillium—the two most common indoor molds—fling out tiny spores and mycotoxins, which can penetrate deep into your lungs.
Even nonallergic folks can experience wheeze-inducing nasal inflammation from inhaling Aspergillus particles, according to a recent study from Finland. Worst case: Fungi can lead to a life-threatening lung infection—made even scarier by the fact that molds are increasingly drug resistant.
Clorox alone won't cut it. Even dead mold can cause allergic flare-ups, EPA experts warn, so you need to kill and remove the fungal funk. If you spot a patch—check damp, dark areas—grab gloves, an N-95 respirator mask, and a stiff brush.
Mix 1 cup of bleach into a gallon of water and scrub the area until no visible mold remains. (Mold can be found in more than just your house! Find out: Is Your Office Making You Sick? Rinse with clean water and let the area dry completely.
Bolster your internal defenses too: Scientists in South Carolina recently linked nasal mold infections to insufficient vitamin D levels. If you're on the low side (as most people are), a D3 supplement may ease your inflammatory response to mold spores, says Dr. Sublett. To determine your dose, ask your M.D. to perform a 25-hydroxy vitamin D blood test.
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If you spend hours holed up in your basement watching sports, you may be inhaling dangerous amounts of radon. The gas, formed when uranium in soil breaks down, seeps into your home through cracks in the foundation.
"Its radioactive particles are deposited in sensitive areas of your lungs, where they can cause changes in your DNA that lead to lung cancer," says William Field, Ph.D, a professor of environmental health at the University of Iowa. In fact, the EPA estimates that radon is responsible for 21,000 U.S. lung cancer deaths every year.
One in 15 American homes have dangerous levels of radon—and the farther north your latitude, the greater your risk may be. The reason: When the air outside is cold, heated indoor air rises, creating suction that can pull radon into your home. (Find out if you live in a high-risk zone at epa.gov/radon/zonemap.html.)
Even if you're not in the Northeast or Midwest (where levels are notoriously high), you should test your home for the gas; there are no warning signs that it's invading your air, says Field. His recommendation: Buy a short-term radon test kit, and if the level is 4 pico-curies per liter (pCi/L) or higher, run a second test, since levels can vary from day to day. If the average of the two readings is 4 pCi/L or higher, call a certified radon reduction specialist.
That "fresh" air may be contaminated with soot, ozone, and metal particles; inhaling this toxic trio can predispose you to memory problems and infertility. It could also be scrambling nervous-system signals that control your heart rate and BP, says Brown University epidemiologist Gregory Wellenius, Sc.D. Need more? A 2012 study in the Archives of Internal Medicine found that exposure to air pollution, even at "safe" levels, may raise your stroke risk. (It's the #5 mankiller in America—Take Our Stroke Risk Quiz before it's too late!)
This is no reason to hang up your running shoes. Regular cardio exercise may actually help prevent particle-induced inflammation, according to a new rodent study in Medicine & Science in Sports & Exercise. Just rethink your outdoor route: Avoid running in areas within a few hundred yards of busy roadways or industrial sites. A shady park near a body of water is ideal because trees and shoreline breezes help diffuse pollution, says Linsey Marr, Ph.D., an associate professor of civil and environmental engineering at Virginia Tech. Traffic unavoidable? Run in the morning, before the sun's rays have converted vehicle exhaust into ozone.
Something nasty may be wafting through your kitchen—and we don't mean the stench of the garbage you were supposed to take out. According to British scientists, the kitchen is one of the primary locations for carbon monoxide (CO) exposure.
Every time you fire up a gas stove, you release the odorless, poisonous gas. Normally the amount is minimal and quickly dissipates. But if your stove burns inefficiently or vents improperly, the noxious gas may be invading your air.
Inside your body, CO clings to red blood cells, displacing the oxygen your brain and heart need to function. Low levels can lead to flulike symptoms, while larger doses can result in brain damage or even death, says Lindell K. Weaver, M.D., a pulmonologist at Intermountain Medical Center in Murray, Utah.
Check your stove, furnace, or fireplace. Is the burner flame yellow instead of blue? Is there soot on any vent or flue? If any answer is yes, your appliance or flue may be functioning improperly and should be checked by a pro, says Dr. Weaver.
Next, make sure your CO alarms aren't installed near vents, which can blow gas away from the sensors. Each alarm should also have an end-of-life signal, which sounds if the unit needs replacement. (The test button indicates only if the alarm is audible, not whether the device works.)
If you travel a lot, buy a portable alarm, such as the BW Honeywell Gas Alert Clip ($135, gassniffer.com). Dr. Weaver's research shows that hotels are hot spots for CO poisoning, since most states don't require alarms in rooms. (Make sure to try this 15-Minute Hotel Room Workout to keep your exercise going even when traveling!)
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Perfluorinated compounds, or PFCs, are slick. Often embedded in furniture, carpeting, and paint, these water-and stain-repelling chemicals can easily escape into the air, according to a new study published in Environmental Science & Technology.
Once inhaled, PFCs can linger in your body for years, potentially altering your levels of testosterone and thyroid hormone, says Olga Naidenko, Ph.D., a senior scientist at the Environmental Working Group. This may eventually lead to low sperm count, thyroid disease, elevated cholesterol, and obesity, she says.
The EPA is working with companies to eliminate PFCs in everything from furniture to food packaging by 2015. Until then, reduce your exposure by avoiding furniture, carpets, and clothing treated with stain-resistant chemicals, and opt for cast-iron and stainless-steel cookware over nonstick pans, recommends Naidenko.
Since you can also ingest the compounds, skip the drive-thru joints—those greasy wrappers often contain PFCs that can leach into your food, according to the Environmental Working Group.
There may be a price to pay for perfuming every last inch of our world. Recent research published in Environmental Impact Assessment Review found that scented air fresheners, lotions, shampoos, soaps, laundry products, and household cleaners emit an average of 17 different VOCs (volatile organic compounds).
A number of these compounds, including formaldehyde, are classified as toxic or hazardous and have been linked to low sperm quality, asthma, and cancer, Steinemann says. (Don't let this happen to you! Protect your sperm and hormones by learning What More Testosterone Can Do for You.)
Whether inhaled through your nose or absorbed through your skin, VOCs can enter your bloodstream and end up in your brain. Depending on the substance, repeated exposure could eventually lead to central nervous system damage.
Manufacturers aren't required to reveal whether fragranced products contain harmful VOCs, so Steinemann recommends ditching scented air fresheners, dryer sheets, detergents, and soaps (including bar soaps).
Even "organic" or "green" fragranced products should be tossed—they're just as likely to spew VOCs, Steinemann's research shows. Since label claims like "fragrance-free" or "nontoxic" aren't always true, check the ingredients, avoiding products that contain "masking fragrance," "fragrance," "perfume," or "parfum."
Finally, spruce up your space with English ivy or asparagus ferns, which can lower VOC levels in indoor air, a 2009 University of Georgia study found.
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