Abstract: The temporal distribution characteristics of five diarrhetic shellfish toxins (DST) and six paralytic shellfish toxins (PST) in oysters cultured in Sanggou Bay were determined by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). At the same time, the adsorption quantities of both kinds of toxins in their growing waters onto HP20 and SP700 macroporous adsorption resins were measured by HPLC-MS/MS to establish the relationships of DST and PST contents between oysters and their growing waters. The results showed that four DST (OA, DTX-1, GYM and PTX-2) and two PST (STX and dcSTX) were detected from both the oysters and seawater samples. During the monitoring period, the shellfish toxins in the seawater increased firstly, reaching a peak, and then gradually reduced. There was a positive correlation between shellfish toxin contents in oysters and their growing seawater. It is surprising that the peak of shellfish toxin contents appeared for oysters 14 days later than for their growing seawater. Thus, solid phase adsorbent and toxin tracking (SPATT) enables warning of the presence of shellfish toxins in oysters 14 days in advance.

Key words: oysters, resins, shellfish toxins, monitoring, early warning