"Phantom smell," also known as phantosmia, is a condition where a person perceives smells that are not present in their environment. This phenomenon can occur due to various reasons, including neurological disorders, sinus infections, or exposure to certain chemicals. The brain may misinterpret signals from the olfactory system, leading to the sensation of smelling something that isn't there. People experiencing phantom smells often describe them as unpleasant or foul, such as the scent of burnt toast or rotten food. While it can be distressing, phantom smell is usually not harmful. Treatment may involve addressing underlying health issues or, in some cases, olfactory training.