DSP toxins are produced by marine algae and are accumulated by shellfish, particularly by mussels. More than five different DSP toxins have been identified so far, but two of them are predominant in Europe (okadaic acid and DTX-1). The consumption of DSP contaminated mussels can cause gastrointestinal disorder. DSP toxins are also considered to be potent tumour promoters. Contamination of shellfish by DSP occurs regularly in Europe and most Community Countries operate DSP monitoring schemes on imports of shellfish and at production sites. The European Community (DG VI - Agricultural Services) is preparing a Directive (COM (89) 645 final) which will establish limits of DSP toxins in shellfish. The method for DSP determination is normally the non-specific mouse/rat bioassay and, to a lesser extent, chemical analysis by HPLC. Development of chemical methods is being hampered by the interference of organic acids with the determination of DSP toxins and by the lack of pure toxins.
The aim is to provide samples of individual toxins, to develop a candidate official method and to raise the reliability of the determination by European laboratories.
Significant quantities of okadaic acid have been produced from cultures of algae. Chromatographic methods for routine monitoring and absolute identification of DSP toxins are being developed. Solutions of okadaic acid, contaminated mussels and mussel extracts for intercomparisons are being prepared. An intercomparison involving some 20 laboratories to assess performance of HPLC methods will be completed in 1992.
Funding SchemeCSC - Cost-sharing contracts
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