12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006Lesser Flamingo in Lake BigMomela.PO.08-1235 times higher content of PTX-2in Dinophysis acuta compared toDTX-1Session: PO.08 - ToxicologyBengt Lundve 1 , O Lindahl 1 , M Sandvik 2 ,T.L Torgersen 2 , L Nguyen 31 University of Gothenburg,FISKEBÄCKSKIL, Sweden2 National Veterinary Institute, OSLO,Norway3 Norwegian School of Veterinary Science,OSLO, NorwayThe diarrhea-producing microalgaeD.acuminata and D.acuta arecommon and known aspectenotoxin producers. In 2001,water samples was taken on theSwedish West Coast at threedifferent depths and analysed forpectenotoxins with LC-MS.Countings of D. acuminata and D.acuta were performed forcomparing toxicity contents in thecells. September samples fromKoljörfjord contained 4000 cells/L ofD. acuta, which causedcontamination of 800 μg DTX-1/kilomussel-meat in blue mussels(Mytilus edulis). The content ofDTX-1 in the D. acuta populationwas approximately 700 ng DTX-1/100L seawater. The D. acutapopulation contained up to 25000ng PTX-2/100L, an amount which is35 times higher. PTX-2 is quicklyconverted into PTX-2 seco acid bythe mussel tissue. The permittedlevel of toxin in mussel meat usedfor human consumption is 5000 μg/kg for PTX-2 and PTX-2 seco acidand 160 μg/kg for DTX-1. Weshould take in consideration that thepermitted level for PTXs is 31,25times higher and 35,7 times forPTX-2 production in D.acuta. Moreattention should be taken todetermine if the permitted level oftoxin content should be increased.PO.07-05Transport of potentially harmfulspecies by density-driven coastaljets in the western EnglishChannelSession: PO.07 - Ecology andoceanographySJ Lyons 1 , L Fernand 2 , R Raine 11 The Martin Ryan Marine Science Institute,GALWAY, Ireland2 CEFAS, Pakefield Road, LOWESTOFTNR33 0HT, United KingdomStrong bottom fronts to the west ofBrittany and along the southerncoast of England exist in thewestern English Channel insummer. Strong flows associatedwith these fronts were evidenced bysatellite tracked drifters. In thecentral region, flows were weakerdue to a combination of tide andwind effects.Noticeably discoloured water in thewestern English Channel in lateJune/early July 2003 was due to abloom of Karenia mikimotoi, celldensities reaching 3.8 million cells/l,with associated chlorophyll levels ofup to 70 mg m -3 . Underwaymeasurements and satellite imageryrevealed the bloom to be located inthe central area of the Channelbetween 3 and 5°W. Cell densitiesof K. mikimotoi were substantiallyreduced in late August whenblooms of Pseudo-nitzschia andEmiliania huxleyi were observed.Multivariate statistical analyseswere used to summarise thephytoplankton data from bothcruises. Without doubt, the mostimportant aspect of physicaloceanography relevant to harmfulevents in the near-shelf/coastal229