First Detection of Paralytic Shellfish Poisoning (PSP) Toxins in Icelandic Mussels (Mytilus edulis): Links to Causative Phytoplankton Species.

peer-reviewedParalytic shellfish poisoning (PSP) toxins were detected in blue mussels (Mytilus edulis) from two harvesting areas, Eyjafjordur on the north coast and Breidafjordur on the west coast of Iceland in 2009. During a bloom of Alexandrium spp. at both locations in June of that year, blue mussels were found to be contaminated with paralytic shellfish toxins (PSTs), leading to extensive closures of these harvesting sites. Phytoplankton data taken during this time showed the presence of large numbers of A. tamarense, with smaller numbers of A. ostenfeldii also being detected. Mussel samples were analysed by mouse bioassay (MBA) and liquid chromatography with fluorescence detection (LC-FLD). Toxicity over 10 times the European Union (EU) regulatory limit was observed in samples from Eyjafjordur while levels over 4 times this limit were detected in samples from Breidafjordur. The toxin profile determined by LC-FLD was found to be composed primarily of the carbamate toxins gonyautoxin-2,3 (GTX-2,3). Saxitoxin (STX) was also detected in all samples analysed and was the second most abundant toxin present. Gonyautoxin-1,4 (GTX-1,4) was detected at lower concentrations in half the samples analysed from both locations. Comparison is made between predicted toxin profiles from these algal species and the toxin profiles determined through LC-FLD analysis. These results represent the first identification and PST profile determination in shellfish harvested from Icelandic waters