Beyond explosion: inhalational toxicity of liquefied petroleum gas

Liquefied petroleum gas (LPG) is commonly associated with explosions, fires, and thermal injuries; however, inhalational exposure can also cause severe or fatal toxicity in the absence of combustion. We comment on a 2026 Legal Medicine report of fatal acute butane poisoning in an elderly woman who was found in an empty bathtub after multiple LPG cartridges had been punctured. The case highlights the potential for gases heavier than air to accumulate in low-lying, recessed spaces and cause lethal inhalational exposure. Butane toxicity may involve multiple mechanisms, including hypoxia, central nervous system depression, and potentially fatal cardiac arrhythmias. Reported cases further demonstrate a clinical spectrum ranging from hypoxic encephalopathy to ventricular fibrillation with successful resuscitation. Importantly, replacing butane with propane should not be assumed to eliminate the risk of fatal inhalational exposure, as both gases can accumulate in low-lying spaces at high concentrations. Thus, LPG-related incidents should be assessed not only for explosion, fire, and thermal injury but also for potentially fatal inhalational toxicity, with attention to gas composition and the physical characteristics of the exposure environment.