Pulmonary damage after modest exposure to zinc chloride smoke

Thirteen soldiers (11 men and two women) were exposed to zinc chloride smok e (ZCS) during a combat exercise. Even though their initial symptoms were m odest, a prolonged follow up with lung function testing and blood samples w as undertaken due to previous cases with fatal outcome after exposure to ZC S. Four weeks after exposure there were statistically significant declines from baseline values in lung diffusion capacity and total lung capacity of 16.2% and 4.3%, respectively. At the same time plasma levels of fibrinogen and zinc were significantly elevated, though mainly within the normal range . All variables showed a tendency towards normalization at follow up 8 week s and 6 months after exposure. These findings indicate an unexpected quanti fiable damage to lung parenchyma with a remarkable delay after modest expos ure to zinc chloride smoke despite sparse initial symptoms. Exposure to high concentrations of ZCS may induce adult respiratory distres s syndrome (ARDS) after a symptom free period of up to 12 days from exposur e. Even though none of the soldiers in the present study developed ARDS the assessment of lung diffusion capacity and acute phase reactants is propose d as a supplement when monitoring patients after exposure to ZCS. (C) 1999 HARCOURT PUBLISHERS LTD.