- Laundry detergent removes rather than kills most allergens like dust mite waste, pet dander, pollen, and mold spores.
- Hot water at 130°F or higher kills live dust mites, while proper machine agitation and thorough rinsing proved more effective than special detergent formulas for reducing allergens.
- Weekly bedding washes with adequate space for garment movement, combined with allergen-proof encasements, significantly reduced allergen buildup and improved washing effectiveness over time.
From pollen-covered clothes to pet hair-laden blankets, your washing machine does more than tackle visible dirt. But when it comes to common allergens, what exactly happens during a wash cycle?
The short answer: Laundry detergent doesn't typically kill allergens. Instead, it helps remove many of them from fabrics so they can be washed away.
Your laundry can collect a surprising number of allergy triggers over time. "Dust mite waste, pet dander, pollen, and mold spores are among the most common," says Noah Pinsonnault, a reviews analyst in the Good Housekeeping Institute's Home Care & Cleaning Lab. Those particles build up naturally through everyday life, whether they're tracked in from outdoors, shed by pets, or concentrated in frequently used bedding.
Most of these types of allergens are proteins, says Derrick Ward, M.D., an allergist at KS City Allergy & Asthma in Overland Park, KS. "Proteins aren't living things, so 'killing' them doesn't really apply. Laundering works mainly by physically removing and diluting those allergenic proteins." The one exception is the dust mite itself, which is a living organism that hot water can actually kill, he says. "However, even a dead mite leaves behind its allergenic proteins, which still have to be washed away."
At the end of the day, the goal of laundry isn't to kill allergens, but to physically remove them from fabrics, so they no longer trigger symptoms. And how effective your wash is less about any "special" detergent and more about how well you remove and rinse those particles away.
How to make your wash more effective against allergens
“For reducing the inhaled allergens that drive most symptoms, the detergent formula matters far less than the water temperature, the mechanical agitation, and a thorough rinse,” says Dr. Ward.
Use the warmest water your fabrics allow
Hot water can help reduce dust mites and improve removal of allergen buildup when care labels permit. Water must be at or above about 130°F to kill live dust mites, says Dr. Ward. "If you cannot wash bedding, stuffed animals, etc., in hot water, put those items in the freezer overnight, and that will also kill dust mites."
Don’t overload the machine
Clothes need space to move so water and detergent can circulate effectively and lift allergens away. Proper rinsing also helps carry allergens out of fabrics rather than trapping them in the load.
Wash high-allergen items regularly
Bedding in particular collects dust mites and other triggers over time, making frequency one of the most important factors, says Dr. Ward, who recommends weekly washes. Prevention techniques, like using allergen-proof mattress and pillow encasements, can also help limit buildup in the first place, making routine washing more effective.
Brigitt is a writer, editor and craft stylist with nearly 15 years of experience. She specializes in lifestyle topics, including home, health, parenting, beauty, style, food, entertaining, travel and weddings. She has written for Glamour, People, Good Housekeeping, Women's Health, Real Simple, Martha Stewart, Apartment Therapy, The Spruce, and more.
