Have you or your child developed a mysterious rash in unmentionable areas of your bodies? If so, you might need to check the labels of any pre-moistened wipes that your family uses for an ingredient that’s causing allergic reactions in many users.It’s not a sudden reaction that happens the first or second time that you use the wipes. For some people, it takes daily exposure over a period of years before they have any kind of bad reaction to the wipes. One mother described to New York’s WCBS her experience after suffering for more than a year from painful, blistering rashes on her hands. “The rash was driving me crazy and it was sometimes showing up on my face too,” she said.

After keeping track of everything that she touched for more than a year, she sought help from an Ohio State University contact dermatitis clinic. Eventually, she solved the mystery: the baby wipes that she used on her kids were destroying her hands. Now she only uses water to cleanse them.

The problem chemical is a preservative used in both baby wipes and pre-moistened toilet wipes for adults. It’s called methylisothiazolinone. Wipe-makers are searching for a replacement, since there could be millions of people affected by allergies.

Test wipes before use on a less sensitive part of your body that’s acceptable to scratch in public: say, your forearm or the back of your hand. If you develop an allergy after use, stop using any products that you suspect might be causing the problem for at least a month, since it can take that long for a rash to clear up.

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