Sodium Lauryl Sulfate (SLS) is a common ingredient found in shampoos, soaps, toothpaste, and detergents as a foaming agent to help provide a rich foamy lather that we’ve come to associate with the feeling of ‘clean’. While generally regarded as safe in limited doses, there are a few reasons we have Sulfates on our Red List of ingredients that you’ll never find in a Rocky product.
Sulfates have been on the radar of organizations like the Environmental Working Group (EWG), and the Campaign for Safe Cosmetics, as they have been linked to issues such as canker sores in toothpaste and eczema in soap. Health Canada has categorized SLES as a “moderate human health priority” and flagged it for future assessment under the government’s Chemicals Management Plan.
In her book Beauty Bible, Paula Begoun (The Cosmetics Cop) writes, "[SLS is] considered a standard comparison substance for measuring skin irritancy of other ingredients. Thus in scientific studies, when they want to establish whether or not an ingredient is problematic for skin, they compare its effect to the results of SLS. In amounts of 2% to 5%, it can cause allergic or sensitizing reactions in lots of people."
One reason for concern is the manufacturing process of SLES through ‘Ethoxylation’ in order to produce a gentler, less irritating version of SLS. Ethoxylation generates a by-product known as 1,4 dioxane, which is a known carcinogen whose track record is much uglier than SLS.
While EWG ranks the overall health concerns as low, you will see there is strong evidence that it could be a human irritant when in contact with the eyes and skin. A peer-reviewed study aimed to demystify negative claims about SLS found no scientific basis to view SLS as a threat. However, the disclaimer notes that there were competing interests as the study was funded by a household company that uses SLS in many of its products.
While studies are inconclusive and the debate continues to unfold, we will be right over here making sulfate-free products that don’t require guesswork because safe, natural and known alternatives DO exist today.
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SLS: What Is It And Why Should I Care?
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