RADS AND RUDS - THE TOXIC INDUCTION OF ASTHMA AND RHINITIS

Inhalation exposures can produce asthma and rhinitis by several mechan isms, Sensitization with the production of IgE specific for a substanc e can lead to symptoms on reexposure via mast cell degranulation and t he release of inflammatory mediators. Some substances, known as enviro nmental adjuvants, enhance the immune response to concomitant exposure s with the environmental adjuvant, Respiratory irritants can lead to a sthma and rhinitis through interaction with chemical irritant receptor s in the airway, leading to release of substance P from sensory nerves and neurogenic inflammation. The reactive airways dysfunction syndrom e is a chronic asthma-like syndrome resulting from a single acute expo sure to a respiratory irritant, while the reactive upper-airways dysfu nction syndrome is chronic rhinitis stemming from an irritant exposure . The dysregulation of neurogenic inflammation by chemical exposures m ay be an important mechanism in the toxic induction of reactive airway s dysfunction syndrome and reactive upper-airways dysfunction syndrome and may play a role in understanding the sick building syndrome and t he multiple chemical sensitivity syndrome.