How to Tell if You Have Dust Mites

Adam Cloe

Dust mites are small organisms that are related to spiders. They live by consuming dead skin cells and are well-suited for warm and damp environments. Dust mites can cause allergies in some people as a result of a protein found on their body, resulting in irritation and inflammation of the nasal passages and sinuses.

Close up of a dust mite.

Dust mites are extremely common, but high quantities of them can result in severe allergies. Dust mites can be detected using several methods.

  1. Purchase a microscope. You do not need a particularly powerful microscope to see dust mites, Environment Safety and Health Online explains, but you will need a device that is capable of at least 10x magnification. Inexpensive microscopes can be purchased at some toy or hobby supply stores or as part of a science kit. Dust mites are between 250 and 300 microns long, which means they are less than half of a millimeter in size.

  2. Collect a dust sample. Dust mites are usually found in areas of the house that are warm and damp, particularly if a large quantity of dust is present. Dust mites are more likely to be found in these areas because of the skin cells that can be found in dust. Dust mites can also be obtained by taking dust from old mattresses, pillows, blankets, upholstery or areas with lots of pet hair, Inspectapedia notes.

  3. Collect a sample using tape. This method works if the dust mites are crawling on your skin, which will produce a short tickling or itching sensation, the Alabama Cooperative Extension System says. Take a two-inch piece of clear tape and place it on the area where you think the mites are crawling. If dust mites are present on your skin, they will stick to the tape.

  4. Examine the samples for dust mites using the microscope. Dust mites have eight legs and are translucent. You may be able to see them in the dust sample or trapped on the tape. Alternatively, you may observe dust mite feces, which will appear as small brown rectangular pellets under the microscope.

  5. Be tested for a dust mite allergy. This is an alternative way of detecting a dust mite infestation, but is only useful if you are experiencing respiratory allergies due to dust mites. Allergy skin testing involves placing a small amount of dust mite extract under the skin, then pricking the skin, which causes the extract to get into the tissue underneath. If the pricked area turns red and swells, you are allergic to dust mites, the Mayo Clinic explains. If you have an allergy to dust mites and develop symptoms of an allergy when you are at home or in someone's residence, it could be a sign of a dust mite infestation.