Allergies - A Guide and Resources to Allergies

A National Survey Shows Americans' Mattresses, Bed Sheets, Blankets and Pillows Can Make Them Sick.

Allergens Produced by Dust Mites in Bedding Are Shown to be the Cause

Can your bed make you sick? The answer is definitely, according to researchers armed with vacuum cleaners who collected samples of the dust in American bedding, analyzed it and compared the health of the owners. The study shows plenty of cause for concern in terms of dust mite and cockroach allergens at levels associated with asthma and allergies. Other studies had already provided mounting evidence that exposure to indoor allergens from dust mites and cockroaches is a risk factor for the development of allergic diseases and asthma.

The study, call "The First National Allergen Survey" was led by scientists at the National Institute of Environmental Health Sciences (NIEHS) (http://www.niehs.nih.gov/), a part of the National Institutes of Health (http://www.nih.gov/) , and done in collaboration with investigators at the U.S. Department of Housing and Urban Development (http://www.hud.gov/) ; Harvard University (http://www.harvard.edu/) , and Westat, Inc. (http://www.westat.com/)  Early results of the study were be presented at the 96th International Conference of the American Lung Association/American Thoracic Society (http://www.thoracic.org/sections/meetings-and-courses/international-conference/index.html).

Details of the study

 Indoor dust from five or six different sites in each of 831 homes from 75 different areas across the U.S. was collected, along with demographic and health information of home occupants. The 75 areas were selected as representative of the U.S. with respect to region, ethnicity, socioeconomic status and housing characteristics.

Survey results suggest that over 45 percent of the U.S. housing stock, or approximately 44 million homes have bedding with dust mite allergen concentrations that exceed 2 micrograms per gram of dust, a level that has been associated with the development of allergies. Of these, over 23 percent of U.S. homes or about 22 million dwellings, are estimated to have bedding with dust mite allergen concentrations that exceed 10 micrograms per gram dust, a level associated with the trigger of asthma symptoms in asthmatics who are allergic to these allergens.

Further, results indicate that 17 percent of household occupants reported problems with cockroach infestations in the year preceding the study. Cockroach allergen is estimated present at detectable levels in bedding in over 6 percent of all U.S. homes, representing almost 6 million households. The number of homes with detectable cockroach allergen is expected to be much higher since the kitchen is typically the most common site of cockroach activity. Data on kitchen levels of cockroach allergen will become available next year.

"This study suggests that a large number of U.S. homes contain dust mite allergen levels which pose a significant risk for the development of allergies and asthma," Patrick Vojta, Ph.D., of NIEHS, said. "There are housekeeping practices as well as allergen proof bedding covers that can be used to reduce exposures to high levels of allergens. For people who are not allergic to these allergens, steps to reduce exposure may reduce the chance of developing allergies and asthma. For those who are already allergic and/or asthmatic, steps to reduce exposure may decrease the frequency and severity of the symptoms of these diseases."

The study was selected as one of only 25, out of the approximately 5,000 presented, to be highlighted for special media attention by organizers of the ALA/ATS meeting.



What to do to prevent or remove dust mite allergens?

The most effective means is to enclose the mattress top and sides with a plastic cover or other dust mite impervious cover (available here, click on allergy bedding on the left in the new page), thoroughly vacuuming mattress pillows and the base of the bed. Put an airtight plastic or polyurethane cover over your mattress. This is the method recommended by Consumer Reports (see their article here ). This tip is number one for a reason: it is in your bed (including the baby's crib) that you are closest to the mites and their feces and enclosing the mattress and pillows in a dust mite cover virtually eliminates the mites here.  There is a website, The Allergy Store, that we recommend that sells allergy controls, like the dustmite-proof fitted sheets. Mattresses covered with "fitted sheets" help prevent the accumulation of human skin scales on the surface.  These sheets have the advantage of being waterproof, too, which helps protect your mattress from spills, babies and toddler's waste, too.

 See this page for much more information about dust mites and how to control them.