SLES is short for Sodium laureth sulfate which is similar to Sodium lauryl sulfate (SLS) but which has been through an additional process called ethoxylation. This process involves treating the detergent with ethylene oxide which makes the molecule more readily water-soluble and potentially less irritating to the skin. Unfortunately, the ethoxylation process can lead to the accidental formation of a toxin called 1,4-dioxane which is known to be carcinogenic.
Although this contaminant should be removed as part of the manufacturing process, in practice this does not always happen, and analysis of products made using SLES have repeatedly shown low level of 1,4-dioxane.
Due to the potential risk of accidental contamination Green People do not use SLES in any of our products.