Fresh laundry may still harbour harmful bacteria

Scott Sutherland

Avoiding the hot-water setting when we we do laundry may lower our monthly energy bill, but what we save there may be costing us elsewhere, as washing in cold or warm water may be leaving a multitude of harmful bacteria on our clothes.

We wash our clothes to get rid of the dirt, sweat, and oils that end up on them from daily wear, and by extension, the bacteria that those impurities carry. However, according to Dr. Lisa Ackerley, a leading food safety expert from the U.K., washing in anything but hot water may be leaving a multitude of harmful bacteria on our clothes and in the washer itself.

"What I think what's been going on is that we've been turning the dial down on the washing machine, so it's quite possible that we could be using 30 degrees, even 40 degrees (Celsius) for washing," Ackerley said during an interview on Canada AM. "And the problem is bacteria actually thrive at those temperatures."

The worst part of this is that, on top of not washing at high enough temperatures, the practice of putting our most heavily 'contaminated' clothes — like underwear — in with the rest of our laundry may just be spreading the worst bacteria around. The detergents in the water loosen the dirt and bacteria, but since the temperature isn't hot enough to kill the bacteria, they get just swirl around in the water and get onto everything.

"You wouldn't want to dry up your surfaces in the kitchen with your underwear," Ackerley said, "so why would you want to actually mix the bacteria from underwear to tea towels in the wash?"

However, environmentalists emphasize that as long as you use the proper detergent for the water temperature, that should be good enough.

"Warm or even hot water is not hot enough to sterilize clothes exposed to fecal matter," Ed Osann, senior water policy analyst for the Natural Resources Defense Council (NRDC), told Yahoo! Shine. "If detergent is formulated for comparable effectiveness in cold water, then no extra benefit would be expected from warm water use."

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A good way to keep your washer clean and reasonably bacteria-free is to start off your laundry by running a load of whites, using the highest temperature, detergent and bleach. Afterwards, dry them on the highest temperature to make sure the dryer is reasonably clean as well.

One thing to avoid, though, is any detergent that bills itself as 'anti-bacterial', since we're dealing with enough resistant bacteria in the world as it is.

(Photo courtesy: Getty Images)

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