This is a localized form of depigmentation that affects the nose and lips. It is caused by eating out of plastic and rubber dishes that contain the chemical pbenzylhydroquinone. This chemical is absorbed through the skin and inhibits the synthesis of melanin, the substance that produces dark pigment in the skin. The involved skin may also become irritated and inflamed.
Treatment: The problem can be corrected by switching to glass, ceramic, or stainless steel bowls for all the dog’s food and water.