What is it:
Cocamidopropyl Betaine is a surfactant. (Surfactants give shampoos and detergents their cleansing and lathering properties.) It's derived from coconut oil and dimethylaminopropylamine.
Why it's a risk:
Cocamidopropyl betaine is a known skin, eye, and lung irritant. Additionally, at high temperatures and under acidic conditions, it can form carcinogenic nitrosamines.
Types of products that use this ingredient:
Shampoo, body wash, dish soap, bubble bath, scrubs
Brands that use this ingredient:
These are the brands we are currently aware of as of the date of this post. If you see a correction is needed or if you have other companies you would like to mention using this ingredient please post it in the "comments" at the bottom of this Chemical of the Day.
Essence of Wellbeing
Kiss My Face
See update below
I've been asked for an update on this ingredient, I've provided little bit of additional information:
The biggest problem that cocamidopropyl betaine has is that its processing aids, amidoamine and 3-dimethylaminopropylamine, can remain in the product. These chemicals can cause contact dermatitis, eye irritation, and other allergic reactions. In fact, the rate of allergic reactions to these impurities is so high that the American Contact Dermatitis Society named cocamidopropyl betaine Allergen of the Year in 2004. Source
Because these chemicals are amines, they can, under certain conditions, create carcinogenic nitrosamines. These nitrosamines not only can lace products, but can also form downstream, contaminating waste water with these carcinogens that are difficult to remove. Source However, to be fair, these nitrosamines are only formed when the product is heated to above 350 degrees, or when the pH is moderately acidic (3.5 or lower). Source
All in all, cocamidopropyl betaine isn't the worst ingredient in the world, but it certainly isn't the best. The primary risks are skin, eye, and lung irritation. The nitrosamine contamination concern is pretty low in my book. HOWEVER, a product containing cocamidopropyl betaine is a detergent-based cleanser, like shampoo or body wash. You'll notice that the first ingredient is probably water. That's what really you should be avoiding. Why? Well, when a formula contains water, it must contain a preservative. Preservatives are the biggest concern in my book, because most of them are known or suspected xenoestrogens, like phenoxyethanol, parabens and honeysuckle extract. Additionally, a company using cocamidopropyl betain in their formula isn't afraid to use other chemicals, so be wary of PEGs, "fragrance," TEA, DEA, and other harmful chemicals. Have a question about an ingredients label? Post your question here!