Identification of yessotoxin in mussels from the Caucasian Black Sea Coast of the Russian Federation.

The toxin load of shellfish hepatopancreas harvested from the Caucasian Black Sea Coast of the Russian Federation was investigated. The majority of the toxin load was shown to be yessotoxin (YTX), 45-hydroxy-yessotoxin (45-OH-YTX), and homoyessotoxin (homoYTX). Concurrent with the mussel intoxication, the dinoflagellates Lingulodinium polyedrum and Gonyaulax spinifera were found in high concentrations.