Thousands of cases of gastrointestinal disorders caused by DSP have been reported in Europe, Japan, South East Asia, North- and South-America (Sechet et al., 1990). The causative dinoflagellates, which produce the toxins are within the genera Dinophysis and Prorocentrum. These dinoflagellates are widespread, which means that this illness could also occur in any other parts of the world. A great number of toxins has been identified including okadaic acid (OA) and associated toxins (DTX 1-4). Levels producing diarrhoea in adults are estimated at ³ 40 µg for OA and ³ 35 µg for DTX 1 (Scoging, 1998).
Onset of disease is within half an hour to a few hours following consumption of shellfish, which have been feeding on toxic algae. Symptoms are gastrointestinal disorder (diarrhoea, vomiting, abdominal pain) and victims recover within 3-4 days with or without treatment. No fatalities have ever been observed.
The toxins are heat stable and survive normal cooking.