Do You Need to Wash New Clothes Before Wearing Them?

Do You Need to Wash New Clothes Before Wearing Them?

A dermatologist has advice on how to handle clothing you just bought

By Heidi Mitchell in the Wall Street Journal

Most people don’t think about where an item of new clothing has been before it comes into their possession. Even with garments that label their provenance, many include materials that were made in one country, dyed in another and stitched together in a third, each with varying laws about allowable levels of chemical use.

One expert, Donald Belsito, a professor of dermatology at Columbia University Medical Center in New York with a specialty in contact dermatitis, explains how lice can linger in fabric and why washing before wearing—maybe even more than once—should be mandatory.

Itchy, scaly, red

There are two major culprits when it comes to allergens in new clothing: dye and formaldehyde resin.

Most synthetic textiles are colored with azo-aniline dyes, which can cause a severe skin reaction akin to poison ivy in the small population of people allergic to them. For others, reactions to dyes are less extreme, and may result in slightly inflamed, dry, itchy patches of skin, Dr. Belsito says.

Until much of the dye is rinsed out—usually in more than one washing—some wearers might notice red, itchy, scaly rashes, “especially near the areas where there is friction or sweating, like the waist, neck and thighs and around the armpits,” he says. Those who are genuinely allergic, however, “may need to avoid the allergen entirely,” says Dr. Belsito, noting that the dye may stick around indefinitely and continue to trigger the allergy.

Urea formaldehyde resins are used to prevent cotton-polyester blends from wrinkling and to limit mildew, Dr. Belsito says. Though most countries regulate the amount of permissible formaldehyde, a 2010 study by the U.S. Government Accountability Office found that some fabrics for sale in the U.S. exceeded allowable levels of the chemical’s resin.

“The high levels didn’t correlate with any particular fabric or country of origin,” says Dr. Belsito, who adds that some of the tested garments were made in the U.S. Allergic contact dermatitis and irritant contact dermatitis, both forms of eczema, can be caused by wearing fabrics containing the anti-wrinkle chemical. Both have similar symptoms—flaky skin and rashes.

Hidden surprises

There is no way to know how many people have touched a piece of clothing or tried it on before you purchase it in a store. You never know what sorts of germs can be living in the confines of the weave, Dr. Belsito says, even when you purchase items made with 100% natural fibers.

“I have seen cases of lice that were possibly transmitted from trying on in the store, and there are certain infectious diseases that can be passed on through clothing,” he says. Lice can’t last long without a host, but they do tend to attach better to natural fibers than synthetics. “The other infestation I’ve seen from clothing is scabies,” he says.

It’s the humidity

Many factories pack chemical satchels into boxes or bags to absorb moisture during the shipping process and to keep fungus from growing.

But depending on the humidity of the country of origin, and the relative humidity inside the packaging, “fungus can hang around for a while,” Dr. Belsito says, though there is no good data on how long and on which fabrics. One chemical previously used to prevent fungus and mold, dimethyl fumarate, was found to cause severe allergic reactions on the skin and is no longer in wide use.

Wash and wear

Dr. Belsito tells all his patients to wash new clothing, whether for themselves or their children, at least once with a double rinse before wearing, no matter the fabric.

“In terms of hygiene, it’s a very good thing to do,” he says. He always runs the cycle twice—sometimes without any soap—before wearing anything he’s just bought: “Being a dermatologist, I’ve seen examples of some strange stuff, so I don’t take any chances.”