Henna (Lawsonia inermis) has been used for centuries as a herbal hair and skin dye, but very little is known about its additives and contaminants that could adversely affect human health. An analytical method was developed to determine organochlorine compounds in henna, as they are still widely used in the areas where henna is grown. Samples were sonicated with n-hexane, extracts cleansed on Fl...