Citric Acid
Sat, August 15, 2009 at 4:53 PM Q. I have noticed that citric acid is in quite a few "natural" products. From shampoo to bar soap. Is it bad for you? It always seems to appear at the bottom of the ingredient list....so I am guessing that there are minimal amounts of it. Just curious....Thanks!!
A. Citric acid is a weak acid present in all citrus fruits; it's what gives citrus that nice sour zing! If it were dangerous, we couldn't eat oranges! As a cosmetic ingredient, it depends on how it's used. Citric acid at full strength can burn skin and eyes (you know the phrase...lemon juice in a paper cut), that's why it gets a little higher risk score in the Cosmetics Database. But used in shampoos and soaps, it's a minimal amount that's used just to "balance" the pH. Soap is naturally alkaline, so some companies add citric acid to lower the pH so it matches skin's natural pH a little more. However, in this case, there's no leftover citric acid because it's combined with the alkali in the soap. When you combine an acid and an alkali, all you get is water and a salt. So, really it's not even present in the soap. Shampoos, if they're detergent based, are different because the citric acid is used to make the shampoo actually acidic. However, it's not really going to be acidic enough to worry about, and having citric acid in it is not going to pose any health risk. The bottom line: you probably don't want to put citric acid on your skin at full strength as it stings a bit (kind of like vinegar) but as used in shampoos and soaps, it's a safe and natural ingredient.
Reader Comments (2)
Hi, I was wondering about the actual preservative qualities of citric acid. thank you!
A product, if it's acidic enough, can be self-preserving, but it has to have a pretty low pH, like 3, in order to inhibit mold growth. This would be pretty irritating on skin due to the acidity.