ENVIRONMENT : The Truth About Dust : Could Those Tiny Particles Be Alive? They Just Mite
The truth about dust comes as rather a shock to many people. After all, their dust doesn’t twitch, or jump around. It looks, if not benign, at least inert.
Looks can be deceiving.
Your house dust is the native habitat of the dust mite--a microscopic arachnid whose ecological niche is to consume the skin scales of humans and other animals.
It’s not what you’d call a glamorous niche, but the dust mite fills it, with spectacular success.
Dermatophagoides pteronyssinus and Dermatophagoides farinae, like the vulture and the hyena, are voracious eaters and scavengers.
Dust mites are relatives of the spider, colorless and so small as to be invisible to the naked eye. They thrive in warm, humid conditions. A gram of house dust (about half a teaspoon, sans fuzz) contains as many as 1,000 of them.
Dust mites don’t fly. And their feet are sticky, so even when dust is disturbed the little arachnids stick to whatever surface they’re on. (It makes them extremely difficult to vacuum.) Because of this, and because the little mites are big by particulate standards, breathing in dust mites is not a problem.
But there is one problem: that same gram of house dust that harbored 1,000 mites also holds some 250,000 of their fecal pellets. And unlike the mites themselves, which don’t make it very far down your airways before becoming trapped, dust mite fecal matter is “of respirable size.”
Dust mite feces--along with decaying dust mite body parts--can be breathed deep into the lower reaches of your lungs. Though they are too heavy to stay airborne for long, they are most numerous in precisely those places where you press your face and breathe in and out for 6 to 12 hours a day. Namely, your pillow and your mattress.
Dust mite particles are highly allergenic. They provoke respiratory ailments such as rhinitis, sinusitis and asthma in millions of people.
Asthma is a chronic inflammation of the airways that results in wheezing or shortness of breath. It is usually triggered by allergies. People of any age may suffer from it, but about half of asthma patients today are between the ages of 2 and 17. It is the most frequent reason for hospitalization and school absence in children under 15.
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Somewhere between 50% and 80% of asthma sufferers are allergic to dust mites.
Asthma is nothing new. What is new is the incredible increase in asthma cases and in deaths from asthma: up 40% since 1982, according to the Centers for Disease Control in Atlanta. Today, roughly 5% of the nation’s population, or 13 million people, suffer from asthma. Though deaths are still relatively rare, the disease is increasing rapidly and researchers aren’t sure exactly why.
Here are two household factors researchers consider possible:
* Energy conservation measures have tightened up houses, drastically cutting ventilation, increasing moisture and contributing to the buildup of unhealthy indoor air.
* With both men and women working outside the home, cleanliness standards have dropped.
Another possible factor suggested by some: exposure to environmental pollutants may be damaging people’s--especially children’s--immune systems, making them more susceptible to disease.
Though researchers don’t know why people seem to be more susceptible to allergies and asthma, they do know that reducing exposure to dust mite byproducts is an essential step in regaining health.
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If you or any of your family members suffer from respiratory ailments, there are a number of things you can do. The single most essential step is to cover your mattress and pillow with dust mite-proof covers.
For around $10, you can buy a vinyl mattress cover at stores such as Target. Yes, this does create the illusion that you are sleeping on a plastic bag. Children don’t seem to mind sleeping on plastic bags, however.
For three times as much and more, you can mail-order a high-tech mattress cover from an allergy supply company. (Some health insurance companies may pay for these; Medicaid does not.)
Now, about the dust bunnies you’ve been turning your back on.
In addition to dust mites, your house dust probably contains a nasty cocktail of old pesticides, mold spores, lead, cadmium, arsenic, polycyclic aromatic hydrocarbons and volatile organic compounds.
Where does this stuff come from?
Some you put there--bombing for fleas, spraying fabric protector on your sofa, sanding the old woodwork.
And you tracked a lot in on your feet. Hence the first step in keeping your household dust to a minimum is a preventive one: Reduce track-in.
The best way to do this is to declare your home a shoe-free zone. You can always make exceptions--the elderly, the very pregnant, the plumber--but if you’re reasonably consistent about it, this policy can greatly decrease your dust quotient.
The next best thing to no shoes is well-wiped shoes. Buy an industrial-grade mat, place it at your doorstep and train family and friends to wipe their feet thoroughly before entering. Vacuum the mat once a month.
Shoes or no shoes, wall-to-wall carpeting is the archvillain of indoor allergy problems--a bottomless reservoir of dust, impossible to clean. If you can, get rid of it. Wood and vinyl floors aren’t cozy for dust mites and are easy to clean. Area rugs can be cleaned with steam or hot water every three years.
Upholstered furniture can also harbor amazing amounts of dust. Flat weave coverings hold less dust than plush ones do, and leather is best of all. When you replace a sofa or armchair, consider buying leather, especially if any family member has allergies or asthma.
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One other option with carpets and upholstered furniture is to rub dust mite-killing tannic acid products into them. These products are available at allergy supply outfits and are safe for humans and pets. They may discolor your furnishings, though. Try a little spot first.
If a family member has allergies, tackle that person’s bedroom first. In addition to putting dust mite-proof covers on the mattress and pillow, look for other ways to reduce dust mite habitat.
Use pull-down shades rather than curtains. Keep shelf acreage down to reduce dust-accumulating surface area. Deep six the rug. And get rid of all those stuffed animals.
If you’re worried about making a child’s room look sterile, get creative with paint. And if you really will wash it, use a washable area rug. Wash it and the bedding in hot water (130 degrees) twice a month--weekly, if your child has asthma.
You’ll be crushed to hear that if you have allergies you should not be doing the vacuuming. If no one else can do it, wear a two-strap dust mask and leave the house for an hour as soon as you’re done.
Vacuuming experts recommend an upright with a beater bar for rugs, and you can now buy high-efficiency bags for ordinary vacuums--a great innovation--at vacuum cleaner supply stores.
Dust mites need humidity. Deprive them of it by increasing ventilation. Crack a window in your room at night and use your kitchen and bathroom exhaust fans whenever you cook or bathe.
If you or a family member has respiratory allergies--and especially asthma--you should probably institute these measures right away, as your doctor has no doubt told you.
If you don’t have allergies or asthma, many of these dust control measures are still a good idea. They will reduce the risk that you and your family members--especially young children--will develop sensitivity to house dust and all it holds.
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Allergy Control Products, (800) 422-3878, and American Allergy Supplies, (800) 321-1096, are mail-order companies that supply mattress covers and other dust mite control products.
