It has been estimated that dust mites and their allergens can be found in about 84% of homes in America. For some people, these housemates can cause respiratory distress that results in what is referred to as "allergenic asthma". House dust mites are arachnids that are related to ticks and spiders. They are too small to see with the naked eye. Dust mites can generally be found anywhere there are people and for those who are sensitive, can create serious respiratory distress.
Dust mites can be found in a wide range of temperatures and humidities. They live in the dust found in carpets, bedding materials, and fabrics such as couches or cloths. Mites can also be found in the dust on the top of HVAC ductwork, water piping, and any other horizontal surface. I have had many people tell me they are allergic to dust, and many times they are unknowingly simply allergic to dust mites and their excrement.
Dust mites require food and water just as any other creature. They live in the dust because of the high organic matter; a lot of dust is composed of people's skin cells and microbial debris. Dust mites can remove moisture from the air through glands along their legs. Thus, as people perspire and leave moisture where they sleep or relax, this high humidity can be absorbed.
Dust mites are a common source of allergens that cause respiratory distress in people. You are not allergic to the mites themselves, and they do not bite you, but they do release large amounts of enzymes (which is a protein) in their fecal pellets, and from that, you can experience an allergic reaction. The proteins in mite fecal pellets are stable at room temperature so they can accumulate in dust over long periods of time. Some studies have indicated that dust mites can produce over 20 pellets a day and over 2,000 during their lifetime. Given the right conditions, adult dust mites live for about 6 weeks. From an egg to a mature adult dust mite takes only 3 to 4 weeks. Once mature, an average female can lay up to 20 eggs a day. Thus, a population of dust mites, and the fecal material they produce, can occur very quickly.
I am not aware of any chemicals that can be applied to a surface to kill dust mites or deactivate the proteins in their fecal material to relieve an occupant of allergy symptoms. Thus, prevention and cleaning are important considerations if you are sensitive to these mites. If some materials are difficult to clean, the exposure to the fecal material can be reduced by covering surfaces with a material barrier such as cloth or cover. Old pillows can be replaced. New pillows, or even bed mattresses, can be placed inside an enclosure. This is like a pillowcase that has a zipper. It is composed of a fabric with at least 300 threads per square inch which will allow air to pass through the fabric but will capture the allergenic-causing particles.
Some compounds are added to fabrics and textiles during their manufacturing that may help in reducing the population of dust mites. This group of compounds is called Acaricides. Some labels on the fabrics do not identify the use of these compounds so you will have to investigate whether the item you are purchasing has been treated.
The reduction of this allergenic asthma can be accomplished by removing the person from the environment, preventing exposure by using barriers or removing the source of the irritant. Studies have shown that killing mites will not stop the exposure and reaction to the allergen. You could kill every dust mite in your home, but unless you remove the allergens (fecal pellets) you will not reduce the amount of allergenic debris or the exposure risk. If the allergens can be removed without killing or removing the dust mites, then the allergenic symptoms will reduce, but quickly rebound, as new fecal pellets are produced.
Thus, to prevent exposure to dust mites, a combination of removing their food and moisture is an important first step. Then, the physical removal of the mites and fecal debris by mechanical removal can be employed to reduce the allergenic symptoms to a sustainable level. Washing with soapy hot water at a temperature of 120 degrees Fahrenheit can kill about 50% of the dust mites. Using hot water with a temperature of 131 degrees Fahrenheit can kill 100% of the dust mites. The surfactant properties of soap have been found to remove much of the allergenic materials in fabrics. Studies using steam have shown that it reduces both the population of dust mites and allergenic compounds.
How do you find out if you have dust mites in your home? Although there have been many studies to determine a method of sampling for dust mites so an accurate population can be determined, so far, a repeatable approach has not been found. The most common way of testing a home is to have a laboratory provide a small attachment with a filter inside to fit on the intake of a small vacuum. The surface of a bed or a couch is vacuumed, and the filter is then submitted to the laboratory for analysis. This type of sampling technique will determine if there are dust mites present, but the quantity will vary based on location or time.
Remember that there are dust mites in every home. Recognizing that the respiratory distress that you experience when you sit on your couch, go to bed, vacuum your carpet, or dust your home, may be the result of dust mites. Also, you may not be allergic to dust, but what is in the dust? Keep the piping in your basement clean of dust by wiping them with a soapy cloth twice a year. You cannot prevent the dust mites from being a housemate, but cleaning with a HEPA vacuum, and maintaining low humidity conditions will be very helpful in maintaining a small population in your home.
At Farsight Management we understand that not all indoor air quality companies are created equal.
We feel that it is imperative to educate ourselves, our employees, and our customers. You can trust that we follow all the national standards in regards to indoor air quality. This includes mold remediation, lead abatement, asbestos removal, and everything that we do.