The impact of pollution on the voice.

Pollution is responsible for the presence of toxic substances and conditions throughout our environment. Inhalation of toxic pollutants may affect the voice adversely by direct laryngeal injury, by causing pulmonary dysfunction that results in voice maladies, or through impairments elsewhere in the vocal tract. Ingested substances--especially those that have neurolaryngologic effects--may also adversely affect the voice. Non-chemical environmental pollutants such as noise may also be responsible for voice abnormalities. Most of the information about the effects of pollution on the voice is anecdotal. Equipment and techniques that permit valid, reliable voice research have recently become available; and studies on the impact of pollution on communication, and specifically on voice, should be encouraged.