Mondo Description A pneumonia that is an acute inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors. It is a sentinel health event (occupational) associated with exposure to ammonia (refrigeration, fertilizer, and oil refining industries), chlorine (alkali and bleach industries), nitrogen oxides (silo fillers, arc welders, and nitric acid industry), sulfur dioxide (paper, refrigeration, and oil refining industries), cadmium (processors and cadmium smelters), trimellitic anhydride (plastics and organic chemical synthesis), and vanadium pentoxide (boilermakers). The two types of pulmonary agents are central and peripheral. Central pulmonary agents, for example, ammonia, are water soluble irritants that injure the upper airways. Peripheral pulmonary agents, for example, phosgene, NOx, and PFIB, are slightly water soluble irritants that injure the alveolar-capillary membranes. Chlorine has both central and peripheral effects.