A method for dispensing an active volatile in the environment surrounding a surface, which comprises applying to the surface a self-adhering, water-resistant gel composition of at least one active volatile ingredient, silica, and a water-soluble cationic polysaccharide, and diffusing or releasing the volatile ingredient(s) from the gel in an amount sufficient to purify or sanitize the surrounding air, both in a dry condition or in the presence of humidity or water. The gel composition remains adhered to the surface and actively releases the volatile ingredient(s) even after being exposed to repeated water flows over the composition.
