Sodium Laureth Sulfate (SLES) is a widely used ingredient found in many personal care and cleaning products. It functions primarily as a surfactant, playing a significant role in how these everyday items perform. Understanding SLES involves examining its chemical properties, its presence in various products, common questions regarding its safety, and available alternatives.
Understanding SLES
Sodium Laureth Sulfate, commonly known as SLES, is an anionic detergent and surfactant. It is typically derived from palm kernel oil or coconut oil through a chemical process called ethoxylation of dodecyl alcohol. SLES functions by lowering the surface tension between liquids and solids, which allows for effective cleaning and the breakdown of dirt and oils.
SLES creates a rich, stable lather, which many consumers associate with effective cleaning. SLES works by forming micelles, tiny structures that encapsulate grease and dirt, making them easier to rinse away with water. Manufacturers often choose SLES because it is an inexpensive and highly effective foaming agent. It is generally considered milder on the skin compared to its close relative, Sodium Lauryl Sulfate (SLS), due to the ethoxylation process.
Products Containing SLES
SLES is common in many personal care and household cleaning products. In personal care, it is frequently found in items such as shampoos, body washes, facial cleansers, and hand soaps. It also contributes to the lather in toothpastes, shaving creams, and bubble baths.
Beyond personal hygiene, SLES is incorporated into many household cleaning solutions. This includes dishwashing liquids, laundry detergents, and various all-purpose cleaners. SLES also has industrial applications as a surfactant in products like herbicides, vehicle cleaning, hard surface degreasing, and textile manufacturing.
Addressing Common Questions About SLES
Concerns about SLES include potential skin irritation and the byproduct 1,4-dioxane. While SLES is generally considered milder than SLS, it can still cause irritation for some individuals. Symptoms may include redness, dryness, itching, or stinging, particularly in those with sensitive skin or when used in high concentrations or with prolonged skin contact. SLES may also strip the skin of its natural oils, potentially disrupting the skin’s protective barrier.
1,4-dioxane is a trace byproduct formed during SLES manufacturing. The U.S. Environmental Protection Agency (EPA) classifies 1,4-dioxane as a “likely human carcinogen” based on animal studies, while the International Agency for Research on Cancer (IARC) lists it as a “possible carcinogen.” Manufacturers employ techniques like “vacuum stripping” to minimize its presence.
Regulatory bodies, such as the European Commission Scientific Committee on Consumer Safety (SCCS), have concluded that trace levels of 1,4-dioxane up to 10 parts per million (ppm) in cosmetic products are considered safe for consumers. New York State has implemented stricter limits, requiring household and personal care products to contain no more than 2 ppm of 1,4-dioxane by December 2022, further reducing to 1 ppm by December 2023. Cosmetics in New York are limited to 10 ppm as of December 2022.
SLES Alternatives
For those seeking SLES-free products, various alternatives provide effective cleansing and foaming properties. Many alternative surfactants are derived from plant-based sources. These options offer different chemical structures that aim to reduce potential irritation while maintaining product performance.
Some common alternatives include plant-based surfactants like Decyl Glucoside and Lauryl Glucoside, which are often sourced from corn glucose and coconut oil. Amino acid-based surfactants, such as Sodium Cocoyl Isethionate, are known for their mildness and ability to create a rich lather. Cocamidopropyl Betaine, a mild surfactant from coconut oil, is also used for its foaming properties and gentle nature. While these alternatives offer different profiles, they can sometimes be more expensive than SLES.