Hot, Not Warm, Water

That’s what it takes to kill dust mites and other allergens in your laundry. Doing your laundry in hot water – 140 degrees Fahrenheit – kills 100 % of allergy-causing dust mites, compared to 6.5% of dust mites when using warm water –104 degrees Fahrenheit. Hotter water is also better at removing dog dander and pollen.

That was reported by researchers recently at the American Thoracic Society International Conference. They compared the effectiveness of washing cotton sheets with regular laundry detergent at various temperatures in removing dust mites, dog dander, and pollen allergens.

The dilemma for many of us may be that we're trying to conserve energy and save money by washing in cold water. But, if you or your children are prone to dust mite allergies, is this a change you're willing to make? Look at these statistics.

Washing in hot water also removed nearly 90% of dog dander compared with about 60% removed in warm water washing. And hot water washing removed nearly 97% of pollen in the laundry compared with 69% at 86 degrees Fahrenheit  and 95% at 104 degrees Fahrenheit.

Note that if you've turned down the thermostat on your hot water heater—commonly done by many with children to prevent scalding—your water may not be hot enough. Check to make sure, and use a laundromat with extra hot water if you must. The water temperature really is that critical.

But what about delicate laundry that can’t take that kind of heat?

Researcher Jung-Won Park offered an alternative to using hot water—washing laundry at a lower temperature between 86-104 degrees F. and then rinsing it in cold water twice, for three minutes each time.

The study also showed that steam cleaning of the sheets was equally effective as hot water washing (140 degrees Fahrenheit) at killing dust mites and removing dog dander and pollen.

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