Fatal Phosgene Inhalation: A Case Report

Phosgene (COCl₂) is widely used in the chemical industry for the manufacture of isocyanates, carbamates, insecticides, herbicides, chloroformates, and pharmaceutical compounds such as barbiturates. Historically, phosgene was also employed as a chemical warfare agent during World War I due to its potent respiratory asphyxiation effects. Nowadays, fatalities associated with phosgene inhalation typically result from accidental occupational exposure in industrial settings. We report two cases of fatal accidental phosgene inhalation at a pharmaceutical industry in Visakhapatnam city. A total of 33 individuals were exposed following a phosgene leak during the manufacture of the anti-retroviral drug lamivudine. Although all affected individuals received initial treatment and were discharged, two developed short term to delayed symptoms and subsequently succumbed to poisoning. Autopsy findings in both cases revealed laryngeal oedema; congested and heavy bluish discoloured lungs; congestion and petechial hemorrhages in the tracheal walls; mucosal erosions in the stomach; along with bluish discoloration and congestion of other viscera. Histopathological examination of the lungs showed congested blood vessels, alveolar spaces filled with inflammatory cells and eosinophilic material, disrupted alveolar septa, and pulmonary oedema. The chemical analysis of viscera detected phosgene and hence the cause of death was determined as phosgene poisoning. Phosgene is a potent respiratory irritant that triggers lipoxygenase-derived leukotriene synthesis, causing systemic inflammation and pulmonary edema. Industrial physicians must be vigilant, and strict safety protocols are essential to prevent accidental exposures. Timely hospitalization and appropriate treatment are critical, as delayed onset of symptoms may occur even after initial recovery.