Sodium Lauryl Sulfate (SLS) ek anionic surfactant hai jo cleansers, shampoos aur toothpastes mein use hota hai. Yeh oil aur dirt ko hatane ke liye aur foam banane ke liye kaam karta hai. Itni strong cleaning power ke wajah se sensitive skin waalon ko irritation ho sakta hai. Patch testing mein bhi iska use ek standard irritant ke roop mein hota hai.