Homicidal Paraquat Poisoning

Paraquat poisoning usually results from suicide, occupational, or accidental exposure. Herein, we report a rare fatal case of homicidal paraquat poisoning. A 58‐year‐old man was poisoned by taking paraquat‐mixed medicine and wearing paraquat‐soaked underwear. In the absence of a history of paraquat exposure, the patient was misdiagnosed with pulmonary infection and scrotal dermatitis and died of respiratory failure 24 days after the initial exposure to paraquat. Ultra‐performance liquid chromatography‐tandem mass spectrometry (UPLC‐MS/MS) was applied to detect and quantify paraquat in postmortem specimens. The concentration of paraquat in postmortem specimens from high to low is lung (0.49 μg/g), brain (0.32 μg/g), kidney (0.24 μg/g), liver (0.20 μg/g), cardiac blood (0.11 μg/mL), and stomach wall (<LOQ). Identification of homicidal paraquat poisoning is not easy for a clinician or a forensic pathologist, it is important to consider the possibility of paraquat poisoning when patients suffer from rapidly aggravating pneumonia of unknown origin.