Recently, Johnson & Johnson reformulated their classic yellow baby shampoo after a consumer outcry over a scary-sounding formaldehyde-based preservative in the product. If it’s not absolutely necessary, there’s no good reason to go slathering a product that contains unnecessary substances on infants. The important question is: should we be worried about formaldehyde in personal-care products at all?

Science writer Tara Haelle examined this question for Slate, approaching it from a global point of view. See, formaldehyde is everywhere: it’s in the air you’re breathing right now, and our own bodies produce it through some metabolic processes. Like most substances, the difference between an average Tuesday and a lethal dose is in the amount you’re exposed to.

You can’t keep your child safe from formaldehyd entirely, at least on this planet. “Unless people calling for removal of quaternium-15 are also keeping their children from eating apples and french fries,” an American University chemist tells Haelle, “I think their activism might be misplaced.”

Factory workers and embalmers come in contact with more formaldehyde than most of us, and they have a higher corresponding risk of certain cancers. The amount of formaldehyde in baby shampoo and the amount of time that a baby ever spends in the bath don’t really add up. One researcher calculated that it would take 40 million baby shampoo baths every day for one baby to reach a level where super-stringent California law Proposition 65 would need to put a “may cause cancer” warning label on it. That would be one pruney baby at the end of the day.

Johnson & Johnson has promised to remove “chemicals of concern” from baby and adult products by next year. That’s good: why keep extra preservatives in a product if they aren’t needed? The public outcry may have been a bit misplaced, though.

No More Formaldehyde Baby Shampoo [Slate]

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