About a decade ago, many tears were shed over J&J’s baby shampoo, not by the babies, but by consumer groups trumpeting the latest chemophobia – formaldehyde, a known “human carcinogen.”
Let’s put the formaldehyde killing our babies meme to its final rest. The only individuals likely to develop leukemia or other rare cancers from formaldehyde are “industrial workers and embalmers,” with long-term, high-level exposure. Susan Goldhaber, our resident toxicologist, has an update on formaldehyde on the website here.
The Environmental Working Group and the Campaign for Safe Cosmetics, the Paul Revere’s of chemophobia, sounded the alarm to consumers. J&J’s baby shampoo, the special shampoo used on our most cared for and most sensitive contained quaternium-15, a preservative. Quaternium-15 breaks down slowly in shampoo and other products, and one of its breakdown products is formaldehyde, an antimicrobial, which presumptively is why it is used in embalming. (We will leave it to A Chemistry Lesson from Hell® to explain the degradation).
The amount of formaldehyde formed in the shampoo was minuscule; Susan’s article will give you a comparison. For our purposes, eating an apple will deliver about 15 times more formaldehyde to your system than the whole bottle of baby shampoo. Faced with increasing maternal concern, J&J made a business decision, removing the preservative, and touting an Improved Formula. While removing quaternium-15, they added phenoxyethanol, sodium benzoate, and ethylhexyglycerin as “components of the new preservative system.” 
Here are two of our original articles on the topic
No More Tears Shampoo, No More Fears? Not So Fast
We urge you to read Susan Goldhaber’s update.
 According to the EWG, sodium benzoate and Vitamin C form benzene, another carcinogen, while phenoxyethanol and ethylhexyglcerin are skin and eye irritants. But oddly, no chemophobic cry about the substitutions from EWG