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Sodium Lauryl Sulfate : The Facts

woman checking for sodium lauryl sulfateOn average women add over 200 chemicals to their skin daily, with more than 60% of these being absorbed directly into the bloodstream. Combine this with chemicals found in hair care and dental hygiene products, such as Sodium Lauryl Sulfate and Sodium Laureth Sulfate and it’s little wonder more and more people are searching for a natural solution.

There are many products labelled as ‘natural’ or ‘organic’ that still contain Sulfates.  The aim of SLS Free is to help you discover products that do not contain Sodium Lauryl Sulfate (SLS) or Sodium Laureth Sulfate (SLES) and learn more about the potential health problems these chemicals can cause.

What Is Sodium Lauryl Sulfate

Sodium Lauryl Sulfate (commonly known as SLS) is a widely used and inexpensive chemical found in many mainstream personal hygiene products such as shampoos, toothpastes, mouthwashes, bodywash, soaps, detergents and body wash , along with Sodium Laureth Sulfate (SLES) and Ammonium Laurel Sulfate (ALS).

SLS is a detergent and surfuctant which essentially means it breaks surface tension which separates molecules and allows better interaction between the product and your hair for instance. This in turn creates a lather which makes products such as shampoo and toothpaste more effective cleaners. So effective and so inexpensive is Sodium Lauryl Sulfate that it’s found in a number of industrial cleaning agents such as engine degreaser and industrial strength detergents. It is also widely used as a skin irritant when testing products used to heal skin irritations.

Is Sodium Lauryl Sulfate A Danger?

There are conflicting reports published over the years and as a result a lot of unsubstantiated claims being made about the use of Sodium Lauryl Sulfate. Most concerning are reports of links between Cancer and SLS.

A Cause of Cancer?

At this point in time there is no scientific evidence that links The use of SLS to Cancer.

There is healthy debate surrounding the topic of SLS and Cancer, however at this point in time there is no scientific evidence that links the two. This has also been backed up by the American Cancer Council along with the Occupational Health and Safety Administration (OHSA) and the National Toxicology Program (NTP).

For more information on SLS and Cancer you can read our article here.

So while any links to Cancer are unsubstantiated there certainly are reports of side effects that have been published. For example, a 1983 report published by The American College of Toxicology (ACT) found that even relatively low concentrations, less than one-half percent, might result in skin irritation.

Higher concentrations were responsible for severe irritation and even corrosion of the skin. The International Journal of Toxicology also provides a safety assessment of SLS and recommends concentration levels of no more than 1% in products with prolonged use, this is disturbing when you consider a number of cleaning products have levels of SLS as high as between 10-20% and in extreme cases over 30%.

In short SLS can cause irritation of the scalp, gums and skin at just 1% and in some people the reaction will be quite strong. We recommend in this case to use a SLS Free alternative such as those listed here.

What’s the Concern over SLES? (Sodium Laureth Sulfate)

Sodium Laureth Sulfate (SLES) is also a concern as in some circumstances it can become contaminated with Dioxane. This largely depends on the manufacturing process. Dioxane is a suspected carcinogen and last much longer in our bodies, primarily because the liver cannot metabolize it effectively. While it’s considered less of a skin irritant when compared to SLS there are underlying concerns over it’s continued use in cosmetic products.

More Than Just A Skin Irritant?

In addition to skin irritation, there are studies that point to residual levels of Sodium Lauryl Sulfate in the brain, lungs, liver, and heart. These levels follow the use of SLS used externally on the scalp and skin, and in the mouth as an ingredient in toothpaste. There are some findings that link the ingredient to a hormone imbalance. Symptoms such as PMS and PMT and menopausal symptoms are tied to hormone levels. There has been a lower rate of male fertility reported in some cases, particularly in western countries however this is as yet unsubstantiated. Because SLS mimics Oestrogen, it is possible it may play a role in these types of health issues. The concern here is while it’s generally considered safe to use at 1% over time the amount absorbed by the bloodstream can mean residual levels in your body are much higher.

Chemical Structure

For those interested in the science behind the speculation, A condition known as protein denaturing is another result of exposure to SLS. The chemical structure forms a bridge between the fat and water soluble portions at the cellular level. This reduces or eliminates the cell’s ability to heal itself. Over time, the destruction of cellular tissue is irreversible. New protein is affected during the construction process and existing protein is damaged. When the protein is damaged, the body has to expend extra energy to try to heal the distressed cells.

Sodium Lauryl Sulfate in soap

SLS and Children

In children, SLS has been linked to eye irritation and poor eye development. Even at very low levels, the product may be absorbed through the skin and cause issues with eye health. It would seem that children’s products should be scrutinized more closely, but often they are not. A number of studies have indicated that SLS will remain in a person’s system (Brain, Heart & Liver) for up to 4-5 days which means if you are using a NON SLS free product at the same volume and same rate of application Sodium Lauryl Sulfate will remain a constant in your body.

Which Household Products Contain SLS

The National Institute of Health publication “Household Products Directory” lists Sodium Lauryl Sulfate as a chemical ingredient in more than 80 products! Some household soaps have a concentration measurement as high as 30 percent. This level is considered unsafe and a likely cause of skin irritation. SLS is also found in Toothpaste, Mouthwash, Makeup, body wash and shampoos.

Sodium Lauryl Sulfate (SLS) is one of the common ingredients used in shampoos. This makes shampoo a frequently reported product to the Food and Drug Administration. Some of the typical reports and complaints include split or fuzzy hair, swelling of the arms, face or hands, irritation of the scalp and irritation of the eyes.

The National Institute of Health publication “Household Products Directory” lists sodium lauryl sulfate as a chemical ingredient in more than 80 products.