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Dust Mite

Dust Mite from Tapelift

This mite was found in a tapelift of settled dust on a shelf in a home. Corn Starch, clothing fibers, skin flakes, and natural minerals are the most common other particles in this view.

Transmitted Oblique Off Crossed Polarized Light Illumination


Mites or their debris are found in indoor environments frequently. They all tend to be small ranging from about 40 micrometers to about a millimeter in largest dimension. They lay eggs and then develop through a number of intermediate stages. The adult mite has 8 legs but the intermediate stages may have 2 to 8 legs, depending on the species and the stage. All mites require a relative humidity above 50% but they will often occupy cooler parts of a home where the relative humidity is naturally higher. They will also inhabit bedding and clothing where the relative humdity is elevated due to the presence of the human body. Their prefered food varies by species. Many of them will survive on skin flakes.

Significance in the Environment:

There are over 124 different types of mites found in homes. Most of these are associated with allergies or asthma. The standard tests for mite allergen can only detect 2 of the 124 mites that may be present. The collection efficiency of a vacuum for even the 2 mites that could be detected is estimated at about 1%. Minor flucuation in that efficiency result in variations of a factor of 20X (2000%). Part of this variation is due to the fact that the mite allergen is often concentrated in a few large particles. The allergen of a few fragments would be swamped by the allergen associated with one whole mite. Tapelifts of settled dusts in homes have been much more consistent in detecting mite problems.

Characteristic Features:

Associated Particles:


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