Fatal hydrofluoric acid poisoning: histologic findings and review of the literature

Hydrofluoric acid (HF), the inorganic acid of elemental fluorine, is a highly dangerous substance and death can result from a very small exposure. In addition to local toxicity, HF can trigger fatal systemic reactions by its high affinity for calcium and magnesium. The authors report the autopsy case of a male worker who was exposed to 50% HF while repairing the leakage from an HF tank valve in a semi-conductor washing factory. His colleagues found blisters on his neck after 6 h of work and he was sent to the hospital. However, he expired from cardiac arrest despite an immediate calcium gluconate injection. At autopsy, burns with eschar covering less than 5% of the total body surface were identified on the neck and around both ears, and microscopic examination of the affected skin revealed extensive necrosis of the epidermis and dermis with pustule formation. In chemical analysis, no fluoride ions were detected in blood, vitreous humor, urine, pleural fluid, bile, or skin tissue from the neck. Considering the chemical burns on the neck and the circumstantial information, the cause of death was determined to be HF poisoning. This article presents the clinical manifestations of local and systemic toxicity after the accidental exposure to a high concentration of HF, with histologic demonstrations of chemical burns.