High amount of dinophysistoxin-3 in Mytilus chilensis collected in Seno de Reloncaví, Chile, during massive human intoxication associated with outbreak of Vibrio parahaemolyticus

Abstract

This study describes the detection of high amount of 7-O-acyl-derivative dinophysistoxin-1 (Dinophysistoxin-3) in filter bivalves collected on February 2005 in the Seno de Reloncaví, Puerto Montt City, Southern Chile, in the same period of time where an intoxication episode was associated with the presence of Vibrio parahaemolyticus in shellfish. The Diarrhetic Shellfish Poisoning (DSP) mouse bioassay of mussel extract samples, performed as described for regulatory testing, were negative to DSP toxins. Therefore, the same mussel samples collected from 8 places of Seno de Reloncaví were then analyzed by the HPLC-FLD method with pre-column derivatization procedure for DSP toxins. The samples showed mainly 7-O-acyl-derivative dinophysistoxin-1 (Dinophysistoxin-3) in concentrations ranging from 190.3 ± 6.8 to 311.1 ± 4.8 ng of DSP toxin/g hepatopancreas and less amounts of Dinophysistoxin-1 ranging from 1.9 ± 1.5 to 11.7 ± 4.6 ng of DSP toxin/g hepatopancreas. After alkaline hydrolysis of