Fatal phosphine poisoning after accidental aluminium phosphide exposure: a forensic case report

Aluminium phosphide is a widely used fumigant pesticide that releases phosphine (PH₃), a highly toxic gas responsible for severe and often fatal poisoning. Phosphine intoxication is characterized by rapid clinical deterioration, severe metabolic acidosis, cardiovascular collapse, and multiorgan failure. From a forensic perspective, the diagnosis may be challenging because autopsy findings are frequently nonspecific. We report a fatal case of phosphine poisoning following accidental exposure to aluminium phosphide (Phostoxin) in a 41-year-old electrician. Clinical, biochemical, autopsy, and toxicological findings were analyzed, with particular emphasis on classical qualitative toxicological methods. The patient collapsed at his workplace after entering a recently fumigated storage facility, resulting in accidental inhalation of phosphine gas. Laboratory investigations revealed severe metabolic acidosis (pH 6.81) with markedly elevated lactate concentrations (up to 25 mmol/L), indicating profound mitochondrial dysfunction. Biochemical findings demonstrated rapid progression of multiorgan failure, including severe myocardial injury, hepatic damage, renal failure, and coagulation abnormalities consistent with disseminated intravascular coagulation. Despite intensive treatment, the patient died 37 h after hospital admission. Forensic autopsy revealed nonspecific findings, including organ congestion and edema, while histological examination was limited by extensive postmortem autolysis. Toxicologicalanalysis of postmortem samples confirmed the presence of phosphine using classical qualitative reactions, including the silver nitrate and ammoniummolybdate tests. This case highlights the diagnostic challenges associated with phosphine poisoning and emphasizes the importance of integrating clinical, biochemical, and forensic findings in establishing the cause of death in suspected pesticide exposures. In addition, it underlines the continued relevance of classical toxicological methods as reliable and accessible tools for confirming phosphine exposure.