ABSTRACT
In the working environment, exposures may result in inflammation of the upper airways: the nasal passages, nasopharynx, sinus, and larynx. In this chapter, the nasal passages are emphasized because of (i) the critical role of the nose in respiratory defenses; (ii) the growing body of epidemiologic and clinical data available on effects of airborne contaminants on the nose; and (iii) the recent concept of ‘‘united airways,’’ that is, airway mucosa forms a continuum from the nose to the lower bronchi (1). Moreover, changes in the inflammatory status of the upper airways can effect asthma, and the vice-versa worsening of asthma has a deleterious effect on rhinitis (2,3). The nasal mucosa can therefore be used as a surrogate to study the inflammatory response in the airways.
