In December 1982, an outbreak of paralytic poisoning occurred due to ingestion of the viscera of a trumpet shell (“boshubora”, Charonia sauliae) in Wakayama Prefecture. Many specimens of this gastropod were collected from adjacent waters and analyzed for toxicity by the routine assay method for tetrodotoxin (TTX). Most of the specimens were toxic: the highest toxicity was 480MU/g digestive gland, and the highest total toxicity per specimen was 37, 000MU.
Attempts were made to isolate the toxin from the toxic digestive glands by a TTX isolation method, which consisted of activated charcoal treatment and chromatography on CM-Sephadex C-25 and Bio-Rex 70. The toxin thus isolated possessed a specific activity of 3, 700MU/mg. It showed thin-layer chromatographic and electrophoretic properties indistinguishable from those of authentic TTX. Both toxins exhibited an identical ¹H-NMR spectrum.
It was concluded from these results that the toxin responsible for this incident of paralytic poisoning was TTX.