Sodium Lauryl Sulfate, Sodium Laureth Sulfate - Sodium lauryl sulfate is a known skin and eye irritant and enhances allergic response to other toxins and allergens. It is used as a lathering agent and detergent, and is present in hundreds of commercial shampoos, body washes, and bubble baths, as well as skin creams and some brands of toothpaste.
When sodium laurel sulfate is combined with ethylene oxide (ethoxylized) to create the milder sodium laureth sulfate, it may become contaminated with 1,4-dioxane, a probable carcinogen. 1,4-dioxane readily penetrates the skin. While 1,4-dioxane can be removed from products easily and economically by vacuum stripping during the manufacturing process, there is no way to determine which products have undergone this process. Labels are not required to show this information. This processing may also lead to the creation of a known carcinogen, ethylene oxide. Ammonium lauryl sulfate is the same compound as sodium lauryl sulfate and has the same uses, but the sodium group has been replaced with an ammonium atom.
Although it is also a skin irritant, ammonium lauryl sulfate is not considered quite as hazardous as sodium lauryl sulfate, unless it is ethoxylized. During its ethoxylation to become ammonium laureth sulfate, it is also likely to be contaminated with 1,4-dioxane, a probable carcinogen, and ethylene oxide, a known carcinogen.