SLS and SLES are mysterious acronyms that, unfortunately, many people do not know the meaning of. In everyday life, we are surrounded by products that help us maintain cleanliness and hygiene – shampoos, soaps, toothpastes, or detergents. However, few of us pay attention to the ingredients of these products, which often hide these mysterious acronyms, such as SLS and SLES. What do they mean, and what impact do they have on our health and the environment? Let’s explain!
What is SLS and SLES in cosmetics?
Sodium Lauryl Sulfate (SLS) is one of the most commonly used surfactants in the cosmetic and detergent industry. It is the sodium salt of lauryl sulfate, giving it detergent and foaming properties. Thanks to these, SLS is ideal for removing dirt and grease, making it a popular ingredient in shampoos, soaps, toothpastes, and other cleaning products. This anionic surfactant has a negatively charged hydrophilic group and a long hydrophobic chain. Such a molecular structure allows SLS to effectively remove impurities.
Sodium Laureth Sulfate (SLES), although it sounds similar to SLS, is a slightly different compound. It is an ethoxylated form of SLS, meaning ethylene oxide is added during production. This makes SLES less irritating to the skin and eyes compared to SLS, making it gentler in everyday-use products.
Both compounds serve similar functions in cosmetics and detergents, but they differ in their irritation potential. SLS is more irritating but simpler to produce. SLES, on the other hand, is gentler but its production process carries a risk of contamination. Both SLS and SLES are biodegradable, meaning they can be broken down by microorganisms. However, this process does not always occur quickly or completely, which can lead to their accumulation in wastewater.
What are the uses of SLS and SLES?
SLS and SLES are two popular surfactants widely used in various everyday products. SLS is used in:
- shampoos – it is a main ingredient in many shampoos, acting as a cleansing agent that helps remove oils, dirt, and styling products from hair and scalp. Its ability to create abundant foam makes shampoos more effective and pleasant to use,
- soaps and shower gels – in these products, SLS acts as a detergent that effectively removes dirt and grease from the skin’s surface, leaving it clean and refreshed,
- toothpastes – SLS is also used in toothpastes, where it helps create foam that distributes the paste across teeth and gums, aiding in the removal of food debris and plaque,
- laundry detergents – SLS acts as a strong degreasing agent, helping remove stains and dirt from fabrics,
- dishwashing liquids – SLS effectively removes grease, ensuring dishes are thoroughly cleaned.
SLES, on the other hand, also appears in shampoos but is gentler on the skin and eyes, making it more suitable for people with sensitive scalps and for children. SLES is also used in some hair conditioners, helping spread the product and making rinsing easier. This ingredient is often chosen for soaps and shower gels for sensitive skin, as its milder action helps avoid irritation and dryness.
SLES and SLS are widely used surfactants whose cleansing and foaming properties have made them common in personal care products and cleaning agents.
Are SLS and SLES in cosmetics a health risk?
Both SLS and SLES are among the most frequently used ingredients in cosmetics and hygiene products. They are found in many shampoos, soaps, toothpastes, etc. When used correctly and under proper conditions, they do not pose a health risk. International standards, including those of the FDA and ECHA, carefully monitor and evaluate the safety of cosmetic ingredients. Products containing SLS and SLES must meet strict safety standards before reaching the market.
Moreover, many studies have shown that SLS and SLES do not pose risks when used in appropriate concentrations in cosmetics. In most cosmetic products, the concentrations are much lower than levels considered potentially harmful. Typical concentrations range from 1% to 10%, while irritation usually occurs above 15%. Additionally, these ingredients have been used in cosmetics and hygiene products for many years, during which numerous studies have confirmed their safety.
Both substances are excellent detergents and foaming agents, allowing cosmetic products to effectively remove dirt, oils, and impurities. This ensures consumers receive products that meet expectations for cleanliness and hygiene. Although SLS and SLES may cause mild irritation in people with very sensitive skin, most users tolerate them well. For those with more sensitive skin, products with reduced concentrations are available.
Are SLS and SLES carcinogenic?
Most studies focus on the irritating properties of SLS. Many reports indicate that SLS may cause skin and eye irritation, especially at high concentrations. However, there is no scientific evidence that SLS is carcinogenic. Toxicological studies have not shown it has cancer-causing properties. Similarly, SLES itself is not considered carcinogenic. The ethoxylation process can lead to the formation of 1,4-dioxane, which is a potential carcinogen. Animal studies have shown it may be carcinogenic at very high doses. However, it is important to emphasize that concentrations of this substance in cosmetics are strictly controlled and kept at very low levels, considered safe for humans.
The FDA does not classify SLS or SLES as carcinogens. Products containing these ingredients must undergo rigorous safety testing before being marketed. The ECHA also does not classify SLS or SLES as carcinogenic. These substances are monitored and regulated to ensure consumer safety. For people with sensitive skin, products containing alternative, milder surfactants are available. Cosmetic companies offer a wide range of products tailored to different consumer needs.
What are the benefits of SLS and SLES?
SLS is known for its ability to effectively remove dirt, oils, and impurities. This makes it a powerful ingredient in body washes, shampoos, and laundry detergents. Its strong degreasing properties make it ideal for applications requiring the removal of heavy contaminants such as fats and oils. SLES has similar cleansing properties but is gentler on the skin. As a result, it is preferred in products designed for people with sensitive skin.
Both substances are also known for their ability to create abundant, long-lasting foam. This not only makes washing more effective but also increases user satisfaction when using cosmetic and personal care products.
At OT.CO Clinic, we understand that patients have different preferences and skin conditions. Not everyone can use the same products and cleansers. That is why we provide professional consultations with cosmetologists and dermatologists to select the appropriate concentration of SLS and SLES. We warmly encourage you to contact us to learn more about our full range of services in this area.
