Sodium lauryl sulfate (SLS) is one of the ingredients you'll find listed on your shampoo bottle. However, unless you're a chemist, you probably don't know what it is. The chemical is found in many cleaning and beauty products, but it is often misunderstood. Urban myths have linked it to cancer, skin irritation, and more. Science may tell a different story.
How it works
SLS is what is known as a "surfactant". This means that it lowers the surface tension between ingredients, which is why it is used as a cleaning and foaming agent. Most of the concerns about SLS stem from the fact that it can be found in beauty and self-care products as well as household cleaners. Sodium laureth sulfate (SLES) is a surfactant with a similar chemical formula. However, SLS is lighter and less irritating than SLS.
Where you’ll find SLS
If you look under your bathroom sink, or on the shelf in your shower, you'll most likely find SLS in your home. It is used in a variety of products, including:
Grooming products such as shaving cream, lip balm, hand sanitizer, nail treatment, makeup remover, foundation, facial cleanser, exfoliant and liquid hand soap.
Hair products, such as shampoo, conditioner, hair dye, dandruff treatment and styling gel.
Dental care products, such as toothpaste, teeth whitening products, and mouthwash
Bath products, such as bath oils or salts, body wash, and bubble bath
Creams and lotions, such as hand creams, masks, anti-itch creams, hair removal products, and sunscreens
You will notice that all of these products are topical, or applied directly to the skin or body. SLS is also used as a food additive, usually as an emulsifier or a thickener. It can be found in dried egg products, some marshmallow products and some dried beverages.
Are there dangers?
The Food and Drug Administration (FDA) considers SLS safe as a food additive. In relation to its use in cosmetics and body products, a safety evaluation study of SLS, published in 1983 in the International Journal of Toxicology (the most recent evaluation), which found that it is not harmful if used briefly and washed off the skin, as the Shampoos and Soaps report states that products that remain on the skin for a long time should not contain more than 1 percent of SLS. needed. However, the same evaluation suggested some potential, though minimal, risk to humans using SLS. For example, some trials found that frequent skin exposure to SLS could cause mild to moderate burns in animals. Nevertheless, the evaluation concluded that SLS is safe in formulations used in cosmetics and personal care products. Since many of these products are designed to be washed off after short applications, the risks are minimal.