Acute fatal poisoning with Tolfenpyrad

The authors present a fatal case of poisoning with Tolfenpyrad (TFP), a pesticide first approved in Japan in 2002. A man in his fifties was found dead in the supine position at his son's home and the small towel with a smell of naphthalene was found nearby. Forensic autopsy was unremarkable, except for a very small amount of LIGHT pink fluid in the stomach, with naphthalene odour. The toxicological analyses revealed the presence of TFP and its major metabolite PTCA (4-[4-[(4-chloro-3-ethyl-1-methylpyrazol-5-yl)carbonylaminomethyl]phenoxy]benzoic acid), together with naphthalene and methyl naphthalenes in the post-mortem sample, with liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) respectively. The plasma concentrations of each substance were quantified as 1.97 μg/ml (TFP), 2.88 μg/ml (PTCA), 1.70 μg/ml (naphthalene), 0.67 μg/ml (1-methyl naphthalene) and 1.44 μg/ml (2-methyl naphthalene). According to these results together with autopsy findings, the cause of his death was determined to be acute Tolfenpyrad poisoning. This is the first case report of fatal poisoning attributable to an intake of TFP product.