Comments |
Toxic pneumonitis is 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 (cadmium smelters and processors); trimellitic anhydride (plastics and organic chemical synthesis); and vanadium pentoxide (boilermakers). [Mullan] Chronic effects that have been reported after heavy exposure include bronchiectasis, bronchiolitis obliterans, and asthma. [LaDou, p. 313] The two types of pulmonary agents are central and peripheral. Central pulmonary agents, e.g., ammonia, are water soluble irritants that injure the upper airways. Peripheral pulmonary agents, e.g., phosgene, NOx, and PFIB, are slightly water soluble irritants that injure the alveolar-capillary membranes. Chlorine has both central and peripheral effects. Peripheral pulmonary agents cause pulmonary edema that is delayed up to 24 hours after exposure. The "4-hour rule" states that the victim has received a lethal dose if pulmonary edema develops within 4 hours. [USAMRICD, p. 19-35] Most of the agents of toxic pneumonitis can also cause chemical burns if vapor or liquid come in contact with the skin. Immediate decontamination with clothing removal and copious water irrigation should be considered for ammonia and other chemicals with significant skin and eye contact. [AHLS, p. 91-95; 480] "Pulmonary parenchymal injury that results from inhalation of irritant substances runs the spectrum of acute lung injury and includes pneumonitis, pulmonary edema, and the acute respiratory distress sysndrome (ARDS). [Rosenstock, p. 334] |