Accidental carbon dioxide poisoning due to dry ice during a funeral wake: An autopsy case

We report the autopsy case of a male in his 60 s diagnosed with carbon dioxide (CO₂) poisoning caused by dry ice for cooling in a coffin during a funeral wake. He was last seen alive, clinging to his family member's body with his head inside the coffin. The autopsy and histological findings did not indicate a specific cause of death. To confirm the concentrations of CO₂ and oxygen (O₂) in the coffin, an experiment was conducted to reconstruct the scene. Based on the experimental results, 9 h after placing dry ice, the CO₂ concentration at the estimated closest point to his head was 24%, a lethal level for CO₂ poisoning. Contrastingly, although the concentration of O₂ had fallen, it never reached a lethal concentration at any of the determination points during the experiment, thereby ruling out asphyxia as a cause of death. Based on our findings, we concluded that the cause of his death was CO₂ poisoning. Forensic pathologists tend to overlook CO₂ poisoning unless suspected, as it does not exhibit specific autopsy findings. For the diagnosis of CO₂ poisoning, it is essential to collect detailed information about the deceased and the scene of death. The toxicity of CO₂ itself is not well known, although dry ice is widely available to the public. In order to make its risk well known, it is necessary to inform people about the dangers of using dry ice.