ADOPTED_FROM:ENV 14194:2002 This European Prestandard specifies a method for the quantitative determination of saxitoxin, dc-saxitoxin and the qualitative determination of neo-saxitoxin, and the gonyau toxins GTX-2 and GTX-3 in mussels. The method can also be used to identify the toxins C-1, C-2, GTX-5 and GTX-6 after hydrolysis and, if these toxins are present, to exclude false positive results for GTX-2, GTX-3, neo-saxitoxin and saxitoxin. For mussel the lowest limit of determination is for saxitoxin 0,04 mg/kg mussel meat and for dc-saxitoxin 0,03 mg/kg mussel meat (signal/noise = 10). The upper limits of determination have not been determined. The limits of detection for C-1, C-2, GTX-2, GTX-3, GTX-5, GTX-6 and neo-saxitoxin have not been determined.