[Determination of phycotoxins in aquatic medium by capillary electrophoresis]

Marine phycotoxins present a major public health problem due to their ability to contaminate seafoods. Toxic phytoplankton is not limited, however, to the coastal areas in Europe. There are more and more problems in freshwater reservoirs, in lakes, and in ponds from which grazing animals get their water. Okadaic acid (OA), a polyether toxin from the marine dinoflagellate, Prorocentrum lima, and microcystins (MCYSTs), a potent hepatotoxic cyclic heptapeptides produced by many strains of cyanobacteria have been shown to be a powerful tumor promotor. Thus, considerable effort has been undertaken to find sensitive and easy detection techniques for the determination of phycotoxins from various matrices (microalgae, freshwater, mussels, fish, ...). Different biological and chemical methods have been developed to identify these toxins in shellfish and fish. The mouse bioassay method has been widely used for the detection of toxins such as maitotoxin and ciguatoxin, which are not easily identified by chemical procedures. In this report we describe a capillary electrophoretic method that enables us to detect okadaic acid, microcystins (MCYST-YR, MCYST-LR, MCYST-RR) and maitotoxin in picogram range.