The analysis of lipophilic marine toxins

Consumption of lipophilic marine toxin contaminated shellfish can lead to severe intoxications. Methods described in European Union (EU) legislation to test for the presence of these toxins are based on a mouse or rat bioassay. These assays are unethical and have a poor sensitivity and selectivity. For this reason there is an urgent need for alternative methods. Most promising alternatives are the methods based on liquid chromatography - tandem mass spectrometry (LC-MS/MS). A LC-MS/MS method with alkaline chromatographic conditions in which we were able to separate and analyze the most important toxins in a single analysis was developed. Furthermore, a clean up procedure based on solid phase extraction (SPE) was developed. A combination of SPE clean up and alkaline chromatographic conditions resulted in reduced matrix effects for all matrices tested (mussel, scallop and oyster). The developed SPE & LC-MS/MS method was in-house validated using EU Commission Decision 2002/657/EC. With respect to accuracy, repeatability, reproducibility and decision limit the method performed well. The method also performed excellently in view of possible new limits that are 4- to 5-fold lower than current limits for some toxins. A collaborative study was also performed for the most important toxins of the lipophilic marine toxin group