In November 2015, a patient presented with symptoms of toxicity after eating whole boiled samples of the scavenging gastropod Nassarius (Alectrion) glans "Kinshibai" in Nagasaki. This food poisoning case was the third recorded in Japan. The case was investigated by evaluation of the toxin profile of the gastropod, and monitoring of tetrodotoxin (TTX) levels in serum and urine sampled from the affected individual. One gastropod contained a harmful dose of TTX (2.5 mg/individual in food residue sample 2). In biological samples, maximum TTX concentrations were 42.8 ng/mL in serum on the day after onset of symptoms. TTX urinary excretion was calculated to be 2.4 mg. From the measured TTX concentrations, it was estimated that a lethal dose had been ingested in this case. Moreover, it was found by LC-QqQ-MS/MS analysis and mouse bioassay that the toxicity of "Kinshibai" was not solely due to TTX. The remaining toxicity was thought to be due to 11-oxoTTX. As in previous poisoning cases, it was concluded that ingestion of this gastropod poses a high risk of food poisoning.
