Ammonium Lauryl Sulfate (ALS) is the common name for Ammonium Lauryl Sulfate (CH3(CH2)10CH2OSO3NH4). The anion consists of a nonpolar hydrocarbon chain with polar sulfate end groups. The combination of non-polar and polar groups gives anionic surfactants properties: it facilitates the dissolution of polar and non-polar materials. This salt is classified as a sulfate ester. It is mainly used as a foaming agent in shampoos and body washes. [1][2] Lauryl sulfate is a very foaming surfactant that partially breaks the surface tension of water by forming micelles at the surface-air interface.
Above the critical micelle concentration, the anions organize into micelles in which they form a sphere with the polar hydrophilic head of the sulfate moiety on the outside (surface) of the sphere and the nonpolar hydrophobic tail pointing inward to the center. The water molecules surrounding the micelles are arranged sequentially around the pole heads, which disrupts their ability to form hydrogen bonds with other nearby water molecules. The overall effect of these micelles is to lower the surface tension of the solution, thereby providing a greater ability to penetrate or "wet" various surfaces, including porous structures such as cloth, fibers and hair. Thus, the structured solution makes it easier for the solution to dissolve dirt, grease, etc. in and on such substrates. However, lauryl sulfate exhibits poor soil suspension capacity.
ALS is a non-toxic cleaner. A 1983 report by the Cosmetic Ingredient Review revealed that shampoos containing up to 31 percent ALS received six health complaints out of 6.8 million sold. Those complaints included two for itchy scalp, two for allergic reactions, one for hair damage and one for eye irritation. [3][4]

The CIR report concluded that ammonium lauryl sulfate and ammonium lauryl sulfate "appear to be safe in formulations designed for intermittent, brief use followed by thorough rinse from the skin surface. Concentrations should not exceed 1% in products intended for long-term use."

All alkyl sulfates were thoroughly investigated by the Human and Environmental Risk Assessment (HERA) project, and they found the results were directly applicable to ALS. Most alkyl sulfates exhibit low acute oral toxicity, no toxicity by skin contact, concentration-dependent skin irritation and concentration-dependent eye irritation. They do not sensitize the skin and did not appear to be carcinogenic in a two-year study in rats. The report found that longer carbon chains (16-18) were less irritating to the skin than 12-15 carbon chain lengths. In addition, concentrations below 1% are essentially non-irritating, while concentrations above 10% are moderately to strongly irritating to the skin