up of fibers from carpets and furniture, grit and sand particles, human skin scales, and food debris. This mixture is combined with allergens from domestic animals, insects, and a variety of microscopic arthropods, bacteria, algae, and fungi growing within the house and other buildings. In addition, air coming into these buildings can carry pollen and molds from outside that then become part of the dust. Because the occupants of a house are inevitably exposed to house dust, any source of foreign protein in the dust is a potential cause of sensitization. Skin testing of patients with asthma or rhinitis initially utilized extracts made from dust collected from their own house (i.e., autologous dust; Kern, 1921); now, however, commercial extracts of house dust are widely used for diagnosis and immunotherapy. In 1980 the U.S. Food and Drug Administration (FDA) estimated that at least 10 million injections of "house dust" extract were administered annually in the United States.

Until 1967, house dust allergenicity was attributed to animal dander, insects, and fungi (Spivacke and Grove, 1925; Vannier and Campbell, 1961). In that year, however, Voorhorst and his colleagues in the Netherlands observed large numbers of mites in dust samples and demonstrated that dust

TABLE 3-1 Biological Sources of Allergens in Houses

Acarids

Fungi*

Dust mites

Dermatophagoides pteronyssinus

Dermatophagoides farinae

Euroglyphus maynei

Blomia tropicalis

Storage mites

Inside

Multiple species including

Penicillium, Aspergillus, Rhizopus, Cladosporium (growing on surfaces or wood)

Spiders

Outside

Entry with incoming air, multiple species

Insects

Pollens

Cockroaches

Blattella germanica (German)

Periplanetta americana (American)

Blatta orientalis (Oriental)

Derived from outside

Other

Crickets, flies, beetles, fleas, moths, midges

Sundry

Horsehair in furniture, kapok

Food dropped by inhabitants

Domestic Animals

Rodents

Cats, dogs, ferrets, skunks, horses, rabbits, pigs

Wild: mice, rats

Pets: mice, gerbils, guinea pigs

* Fungal spores may contain very little allergen and may require germination to produce significant exposure.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement