Why does carpet cause allergies in some people?

Carpet Allergens: Mites, Mold and More

Dust mites burrow deep into a carpet's fibers, depositing large amounts of waste that provoke allergies.
Dust mites burrow deep into a carpet's fibers, depositing large amounts of waste that provoke allergies.
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Just about anything can find its way into the welcoming fibers of your carpet. Dust mites and pet dander are two major sources of some of the most aggravating allergens, but other irritants such as dust, mold, dirt and pollen tracked in from outdoors regularly build up as well.

If you have a persistent allergy, then you're probably no stranger to dust mites. These microscopic arthropods may be the most common cause of year-round allergies. According to the Asthma and Allergy Foundation of America, more than 20 million Americans are allergic to these little buggers. Technically, the dust mite's waste is the actual allergen, and they emit impressive amounts of it. Dust mites produce up to 200 times their body weight in waste each day [source: Asthma and Allergy Foundation of America]. Dust mites hide deep in carpeting, bedding and furniture, especially in warm, humid environments. Regular cleaning is no match for them either: 95 percent may remain even after vacuuming [source: Asthma and Allergy Foundation of America].

Cuter than dust mites, but perhaps no less aggravating to your allergies are Fido and Fifi. Your dog and cat, precious as they are, provoke allergies in 15 percent to 30 percent of people with allergies [source: Asthma and Allergy Foundation of America]. Their saliva, urine and other secretions contain proteins that are potential allergens, while their hair often traps dust, fleas and pollen that gets lodged in carpeting when the animals shed. The dead skin, or dander, of our furry friends also collects on surfaces like carpet. Pet allergens are especially problematic because they're sticky and cling to surfaces, and when they're disturbed, they hang out in the air for a long time. Even people who don't own pets get exposed to pet dander because it hitches rides on clothing.

Aside from dust mites and man's best friends, mold can be another common cause of indoor allergies. High humidity, spills that aren't cleaned up and leaky ceilings (or dogs) can all contribute to mold growth. Even shampooing or damp cleaning your carpet can promote the spread of mold and mildew if you don't dry it thoroughly. Whenever the source of the mold is disturbed, the spores are dispersed throughout the air.

Finally, anything that you might be allergic to outside could also become a potential problem inside. As you traipse into your living room after a nice walk through your yard, you may also be bringing in loads of pollen and dust. Where does that pollen and dust go? It goes right to the party that the dust mites and dander already have under way.

Learn how to break up this party on the next page.