This is the next instalment in our ongoing series about chemicals often found in home and personal care products. Here, we make an assessment of ingredients, so you can make informed choices about the products you buy.
Today, we're looking at potassium sorbate. It's a natural preservative with a wide variety of uses.
What is potassium sorbate?
Potassium sorbate is a salt of sorbic acid. It's a natural organic compound found in the berries of the mountain ash. It acts as a preservative in foods, drinks, dietary supplements, personal care products, and cosmetics.
Potassium sorbate comes in two forms. It occurs naturally in certain fruits, and can also be nature identical. Nature identical is chemically the same as the version found in nature, but is made in a factory. Commercially available potassium sorbate is mostly of the nature identical kind.
What is potassium sorbate used for?
Potassium sorbate prevents the growth of moulds and yeasts in foods like jams, cakes, cheeses, maple syrup, and dried meats. It increases the shelf life of herbal dietary supplements and is a wine stabiliser. In addition, the milkshakes you get at fast food chains usually contain potassium sorbate as a preservative.
Manufacturers add potassium sorbate as a preservative to many personal care and beauty products. It helps prevent the growth of bacteria and mould.
You’ve probably heard that contaminated makeup can cause infections. This is why makeup has a shelf life. It's also why you should throw out your mascara after three months. Even if makeup doesn’t have visible mould growth, it may already be contaminated with harmful germs.
This is because many cosmetics and personal care products contain water that can become breeding ground for bacteria. A preservative prevents this from happening and helps ensure that these products stay safe to use.
Is potassium sorbate safe?
Scientists began chemically synthesising potassium sorbate in the early 1900s. It first became a food preservative in the ‘40s. Because it's been around for years, scientists have heavily tested it for safety. Studies indicate that potassium sorbate has almost the same toxicity as table salt. When it's used in the recommended dilutions, it is non-sensitising and non-irritating.
EWG gives potassium sorbate a score of three and reported that its overall hazard rating is low. Additionally, it doesn't persist in the environment and doesn't become concentrated in the bodies of living things. The main problem with the chemical is that, in its pure form, it is a skin and respiratory irritant.
The Centre for Science in the Public Interest labels potassium sorbate as safe. So does the US Food & Drug Administration and the Natural Products Association. A study in the Journal of the American College of Toxicology found the natural preservative safe as a cosmetic ingredient.