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 2006In vitro interactions betweenseveral species of harmful algaeand hemocytes of bivalvemolluscsSession: PO.05 - Toxin analysisHT Hegaret 1 , GH Wikfors 2 , SEShumway 11 University of Connecticut, GROTON,United States of America2 NOAA-NMFS, MILFORD, CT 06460,United States of AmericaHarmful algal blooms (HABs) canhave noxious and sublethal impactson shellfish. The northern quahog (=hard clam), Mercenaria mercenaria,can experience blooms of severalHAB species, includingProrocentrum minimum,Heterosigma akashiwo andAlexandrium fundyense. Tounderstand the possible roles of thehemocytes in bivalve responses toHABs, and how the algal cells areaffected by these responses, in vitrotests of interactions between thoseharmful algae and hemocytes of M.mercenaria were carried out. Wemeasured possible differences inhemocyte parameters attributable toharmful algae and also the effect ofhemocytes on the algaethemselves. Using microscopic andflow-cytometric observations,changes in hematology andphysiology, including cellconcentration, phagocytosis,adhesion and oxidative burstresponse of hemocytes weredetermined. Changes in thephysiology and the characteristics ofthe algal cells including mortality,size, chlorophyll fluorescence andinternal complexity were alsodetermined. The results show aspecies-specific response of thehemocytes depending upon theharmful algae to which they wereexposed. Thus, in vitro tests allow abetter understanding of the role ofthe hemocytes and the hemolymphin the defense mechanisms inmolluscan shellfish to harmful algalcells.PO.05-27Newly discovered brevetoxinoxidation products in marineaerosol: assessing potentialpublic health impactsSession: PO.05 - Toxin analysisMichael S Henry 1 , RH Pierce 1 , PCBlum 1 , KL Lemkau 1 , B Kirkpatrick 1 , SEOsborn 1 , YS Cheng 2 , Y Zhou 2 , LEFleming 3 , LC Backer 4 , S Plakas 5 , AAbraham 5 , R Dickey 5 , A Reich 6 , ABourdelais 7 , J Naar 7 , DG Baden 71 Mote Marine Laboratory, SARASOTA, FL,United States of America2 Lovelace Respiratory Research Institute,ALBUQUERQUE, NM, United States ofAmerica3 NIEHS MFBS and NSF NIEHS OHHCenter, MIAMI, FL, United States ofAmerica4 Centers for Disease Control, ATLANTA,GA, United States of America5 FDA, Gulf Coast Seafood Laboratory,DAUPHIN ISLAND, AL, United States ofAmerica6 FL-Department of Health, TALLAHASSEE,FL, United States of America7 Center for Marine Science-UNCW,WILMINGTON, NC, United States ofAmericaThe toxic dinoflagellate, Kareniabrevis, produces polyetherneurotoxins (brevetoxins or PbTx)that cause massive aquatic animalmortality and neurotoxic shellfishpoisoning (NSP). A uniquecharacteristic of K. brevis blooms isthe associated airborne brevetoxincomponent that results in severerespiratory problems in exposedpopulations. This study wasundertaken in collaboration withhuman exposure studies todetermine the composition ofaerosolized brevetoxins to whichbeachgoers are exposed during a189