Abstract

In areas where toxic algal blooms occur, the organisms primarily affected are shellfish, which, because of their high levels of filtration (clearance rate), accumulate high concentrations of nutrients and toxic phytoplankton in their visceral tissue. This accumulation of toxins in shellfish leads to distribution of these toxins to their different non-visceral tissues. This leads to a variation of assimilated toxic profiles (dinoflagellates) through different biotransformation routes (enzymatic and nonenzymatic) present in the different species of shellfish that may be affected by Harmful algal blooms (HABs), which transforms them into powerful vectors of different groups of toxins. The generated toxic variability can be promoted through the transfer of toxins through the food chain, thusallowing the accumulation of toxins in various living organisms that inhabit in the ocean (zooplankton, fish, gastropods, sea lions and whales). This has been important in determining the potential biotransformation forms and degrees of purification occurring in different marine species affected by toxic blooms. The lipophilic toxins identified in shellfish correspond to a broad spectrum of toxins consisting of the okadaic acid-group (OA-group), Pectenotoxins group (PTX-group), Yessotoxin group (YTX-group) and Azaspiracid group (AZA-group). In the present study, a high performance liquid chromatographic MS/MS method was optimized for the simultaneous determination of OA-group, PTX-group, YTX-group and AZA-group in multiple endemichydrobiological organisms (bivalves and gastropods) of the southern sea of Chile. The toxins were extracted from hydrobiological organisms using standard operating procedures. The result reveals that liquid chromatography coupled to mass spectrometry (LCMS/ MS) allows for the rapid and sensitive determination of lipophilic toxins with minimal sample clean-up, allowing for the detection of biotransformation levels in different hydrobiological organisms with high commercial level.