Chemical treatments are usually the remedy of last resort when addressing dust mite management in the home, and for good reason. Many persons allergic to dust mites and their waste products also have chemical sensitivities, often on multiple levels. Still, one might consider one or both of two kinds of chemical treatments:
Acaricides that kill the mites themselves.
Tannic acid that denatures (de-activates) dust mite allergens.
Both kinds of treatments are generally recommended for carpets rather than mattresses and bed linens, and you might decide to employ them only in other rooms, leaving the bedroom chemical-free. Dust mite mattress covers are recommended by almost all Doctors and Allergists as the first step for dust mite allergy relief.
Also known as “miticides,” these chemicals are specifically tailored to kill mites. Technically, there are no acaricides approved for dust mites to date, but products containing benzyl benzoate as the active ingredient do achieve some effect. The trade name “Acarosan” is applied to those products, which come in a powder or spray for application to carpets. A typical application procedure is as follows:
Apply product in evening, brushing it into the carpet.
Allow product to remain in carpet overnight, for twelve hours.
Brush the product into carpeting again the following day.
The effects of the treatment may last anywhere from six weeks to three months, at which time it will need to be repeated. Note that the potency of benzyl benzoate products declines while in storage, so it is best to use products promptly and completely.
While benzyl benzoate is also the active ingredient in some topical treatments for scabies, it is not wise to allow children to play on carpets with Acarosan residue prior to vacuuming.
Tannic acid works by changing the chemical configuration of dust mite allergens, disabling their ability to elicit allergic reactions in hypersensitive persons. Unfortunately, because tannic acid does not kill the mites themselves, the effects of treatments are relatively temporary. A four hour treatment only lasts 6-8 weeks.
Tannic acid also has the potential to discolor pale carpets, especially with repeated use over time.
Tannic acid neutralizes pet dander allergens, too, but ironically an excess of cat dander allergens can inhibit the effects of tannic acid on dust mite allergens.
A study conducted in Egypt, and published in the Journal of Zhejiang University Science B in 2006, shows that several natural “essential oils” and some naturally-occurring monoterpenoids, have the potential to kill dust mites with fewer side effects than current products. Over a 48-hour period, clove, matrecary, chenopodium, rosemary, eucalyptus, and caraway (listed in order of effectiveness) all achieved substantial dust mite mortality. Additionally, thymol and cinnamaldehyde also demonstrated excellent mite-killing ability. Chlorothymol proved better still (with the addition of chlorine to the thymol molecule). This is promising news indeed.