au développement du phytoplancton ciguatérigène en Polynésie française: CARISTO-Pf n7937/MSR/REC of 4th of December 2015 and Arrêté nHC/491/ DIE/BPT of 30th March 2016). Figure 2. Comparison of Pacific ciguatoxins (P-CTXs) profiles in A) in vitro cultures of Gambierdiscus polynesiensis (TB-92 [14]), B) Tectus niloticus (Nuku Hiva, July 2014 [9]) and C) Tripneustes gratilla (Nuku Hiva, July 2015 [11]) of the toxins involved [9, 11]. Toxicity analysis using the neuroblastoma cell based assay (CBA-N2a) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed the presence of several congeners of P-CTXs in T. niloticus and T. gratilla toxic samples, at levels consistently above the safety limit recommended for human consumption (0.01 ng P-CTX1B/g of tissue [12]), i.e. 11.47 and 20.19 ng P-CTX3C equiv/g of tissue, respectively. These results suggest that T. niloticus and T. gratilla are able to naturally bioaccumulate P-CTXs in their tissues [9, 11]. Interestingly, these findings were consistent with Gambierdiscus abundance data from Anaho Bay obtained using both the natural (i.e. macroalgae) and the artificial (i.e. window-screens) substrate methods [13]. Enumeration of Gambierdiscus cells achieved both microscopically and by way of quantitative polymerase chain reaction (qPCR) assays allowed to confirm that Gambierdiscus populations were present in this area, while qPCR estimation of the relative distribution of Gambierdiscus species in Anaho Bay revealed that G. polynesiensis was the dominant species in this toxic area [9, 11]. This species is known to produce P-CTX3C, 3B, 4A, 4B and M-seco-CTX3C as the major CTXs congeners in cultures [14]. The LC-MS/ MS analyses performed on T. niloticus and T. gratilla samples showed that PCTX3B was the major congener present, followed by P-CTX3C and to a lesser extent, P-CTX4A and P-CTX4B (Fig. 1) [9, 11]. Of note, P-CTX3B is also the major congener found in Tridacna maxima experimentally fed G. polynesiensis cells [15]. All these observations suggest that HARMFUL ALGAE NEWS NO. 60 / 2018 Gambierdiscus is the likely source of the P-CTXs congeners detected in these marine invertebrates. Sea urchins also contained a significant amount of 51-OH-PCTX3C (Fig. 2), an analog considered to be favored through metabolization in trophic food webs [11]. Additionally, the field-surveys conducted in Anaho Bay at different time periods emphasized the slow depuration rate for CTXs in both T. niloticus and T. gratilla toxic samples. The mechanisms controlling the uptake, metabolization and depuration of CTXs in CFP-prone marine invertebrate species are still poorly addressed, thus stressing the need for further investigations. Such knowledge will undoubtedly benefit both ciguatera risk management programs and predictive models of CTX accumulation in these organisms. In conclusion, these recent results provide evidence that a variety of marine invertebrates actually represent a potential bioaccumulation pathway for ciguatera toxins in marine food webs. Considering that most CFP monitoring programs currently rely on the survey of Gambierdiscus cell densities and species composition and/or the monitoring of CTXs in fish, these novel findings highlight the importance of also taking into account the toxicity of marine invertebrates whose consumption may pose a prominent health risk for populations in CFP prone areas. Acknowledgments The present work was supported by funds from the countries of France and French Polynesia (Contrat de Projet Caractérisation et gestion des risques environnementaux et sanitaires liés References 1. Bagnis R 1967. Bulletin de la Société de Pathologie Exotique Tome 60(n6): 580592 2. Laurent D et al 2012. In: Food Chains: New Research. Chapter 1. Nova Science Publishers, Inc.; pp 1-43 3. Rongo T et al 2011. Harmful Algae 10: 345-355 4. Earle KV 1980. Transitions of the Royal Society of Tropical Medicine and Hygiene XXXIII(4): 447-452 5. Randall JE 1958. Bull Mar Sci 8(3): 236267 6. Pawlowiez R et al 2013. Food Addit Contam Part A 30(3): 567-586 7. Mak YL et al 2013. Environ Sci Technol 47: 14070-14079 8. Silva M et al 2015. Toxins 7: 3740-3757 9. Darius HT et al 2018. Toxins 10(1): 2. doi:10.3390/toxins10010002 10. Gatti CM et al 2018. Toxins 10(3): 102. doi:10.3390/toxins10030102 11. Darius HT et al 2018. Mar Drugs 16(4): 122. doi:10.3390/md16040122 12. FDA: Fish and Fishery Products Hazards and Control Guidance. https://www. fda.gov/food/guidanceregulation/guidancedocumentsregulatoryinformation/ seafood/ucm2018426.htm 13. Tester PA et al 2014. Harmful Algae 39: 8-25 14. Chinain M et al 2010. Toxicon 56: 739750 15. Roué M et al 2016. Harmful Algae 57(Part A): 78-87 Authors H Taiana Darius, Jérôme Viallon, Clémence M Gatti & Mireille Chinain, Institut Louis Malardé (ILM), Laboratory of Toxic Microalgae - UMR 241-EIO, PO box 30, 98713 Papeete, Tahiti, French Polynesia Mélanie Roué, Institut de Recherche pour le Développement (IRD) - UMR 241-EIO, PO box 53267, 98716 Pirae, Tahiti, French Polynesia Manoella Sibat, Zouher Amzil & Philipp Hess, IFREMER, Phycotoxins Laboratory, F-44311 Nantes, France Mark W Vandersea & R Wayne Litaker, NOAA, National Ocean Service, Centers for Coastal Ocean Science, Beaufort Laboratory Beaufort, North Carolina, USA Patricia A Tester, Ocean Tester, LLC, Beaufort, North Carolina, USA Corresponding author: tdarius@ilm.pf 7 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 60 - July 2018 www.ioc-unesco.org/hab Marine eukaryote and HAB monitoring in Japan with next generation technology Sequencing technologies such as Illumina MiSeq have made it possible to obtain billions of sequence reads in a Frequency distribution (%) the surface data was used in this study. Surface seawater (0.5 L) was collected weekly with a plastic bucket during the same period. For MPS-based monitoring based on amplicon-seq of 18S-rRNA gene (V79 region), PCR amplification and 454 pyrosequencing were performed accor Inland Sea, 2-17-5 Maruishi, Hatsukaichi, Hiroshima 739-045, Japan Hiroshi Shimada, Central Fisheries Research Institute of Hokkaido Research Organization, Hamanaka-cho 238, Yoichi, Hokkaido 0468555, Japan Seiji Katakura, City of Mombetsu, Kaiyo-koryukan, Kaiyo-koen, Mombetsu, Hokkaido 094-0031, Jap Quantifying dinoflagellate cysts in bottom sediments: a response to Anderson 2018 Problems associated with quantifying dinoflagellate cysts in bottom sediments featured prominently in Don Anderson s personal retrospective view of his contribution to the early days of HAB cyst research published rece viously, sample sites should be chosen to avoid such areas if possible. Clearly, there is room for questions or criticism when this dynamic system is modelled from the assumption that bottom sediments, for example in Anderson s work in The Gulf of Maine, are in a static stable condition whereby a sa Contribution of marine invertebrates to Ciguatera poisoning : the case study of French Polynesia Reported as early as the 15th century by explorers, ciguatera fish poisoning (CFP) is the most prominent non-bacterial seafood poisoning worldwide. Widespread in tropical and subtropical regions, CFP res au développement du phytoplancton ciguatérigène en Polynésie française: CARISTO-Pf n7937/MSR/REC of 4th of December 2015 and Arrêté nHC/491/ DIE/BPT of 30th March 2016). Figure 2. Comparison of Pacific ciguatoxins (P-CTXs) profiles in A) in vitro cultures of Gambierdiscus polynesiensis (TB-92 [14]) Solid Phase Adsorption Toxin Tracking (SPATT) technology for field monitoring of Gambierdiscus toxins with passive samplers Ciguatera poisoning is a seafood intoxication classically associated with the consumption of tropical coral reef fish contaminated with ciguatoxins (CTXs), although some marine Fig. 2. Summary of the results demonstrating that SPATT passive sampling could advantageously contribute to the reinforcement of ciguateric risk assessment and management programmes as a supplementary tool. or of very low densities of toxic Gambierdiscus cells. However, CTXs were detected in numero New limits of Ostreopsis distribution in the Bay of Biscay: a first report of Ostreopsis in Santander Bay, Cantabria (Northern Spain) Fig. 1. Location of sampling sites The genus Ostreopsis encompasses benthic dinoflagellates that represent one of the main microalgal threats for beach tourism in w Bloom of Ostreopsis cf. siamensis in Lisbon Bay Fig. 1. Sampling sites on Lisbon Bay Reports of benthic HAB events have increased during the last decade in temperate regions. These have been associated with proliferations of benthic toxic dinoflagellates, in particular species of Ostreopsis. The M Table1 1- List - List the macroalgaecommunity communityspecies species Table ofof the macroalgae ITSA and ITSB primers [6]. Phylogenetic analysis (not Asparagopsis armata Corallina sp. shown) revealed that all the Caulacanthus ustulatus Cystoseira sp. studied sequences grouped Ceramiacea Derbesia s A possible link between the breakdown of a fertilizer tank and a toxic Pseudonitzschia bloom fishery, leaving toxic blooms undetected in other areas. By the time of the bloom, the diatom community primarily consisted of P. seriata (Fig. 3). Identification of P. seriata as the potential culprit diat Fig. 3. Pseudo-nitzschia seriata TEM micrograph of the poroid structure arranged within the striae consisting of two outer rows of larger poroids and one or two inner rows of smaller poroids. induce DA production in P. australis [7], and the most potent DA-inducing N form has been shown to be urea. Golden alga Prymnesium parvum Carter bloom off Azhikode, southwest India In September 2009, during the southwest monsoon season, a quasi-monospecific bloom of Prymnesium parvum was collected off Azhikode (10o 11 02 N; 76o 09 22 E), on the southwest coast of India (Fig. 1). A conspicuous pale browni Regional Workshop on Monitoring and Management Strategies for Benthic HABs if possible, establish tools for standardized procedures. The exercise is open to the entire international community. The goal of achieving improved assessments of the risks associated with BHABs will help reduce the health, Workshop on morpho-molecular methods for the study of dinoflagellate cysts A workshop on techniques for the morphological and molecular identification of cysts from toxic HAB species, led by Drs Kenneth Neil Mertens, Kirsty Smith, Lesley Rhodes and Lincoln MacKenzie, was held recently at the Cawthro Cawthron Summer Scholar Explores Bloom-Forming Freshwater Cyano bacteria Globally, cyanobacteria blooms in freshwater environments are causing water quality problems and health risks with increasing frequency. New Zealand is no stranger to this, suffering from blooms of toxin-producing cyanobacteria Canadian HAB Scientists Hold Workshop to Establish National Priorities and Develop Research Network A National Harmful Algal Bloom (HAB) workshop was organized and chaired by Dr. Ian Perry at the Institute of Ocean Sciences (IOS), Fisheries and Oceans Canada (DFO), Sidney, British Columbia, July 11- Joint FAO, IAEA, IOC and WHO Technical Meeting for the development of an InterAgency Global Ciguatera Strategy Harmful Algae News has previously brought information on an initiative between the International Atomic Energy Agency (IAEA) Environment Laboratories in Monaco jointly with the Oceanographi 12th Advanced Phytoplankton Course - APC 12 Identification, Taxonomy, Systematics Roscoff Biological Station (France) - 19th May to 8th June 2019 APC12 is organized by the Station Biologique de Roscoff together with the Stazione Zoologica Anton Dohrn and the IOC Science and Communication Centre on H ICHA 2018 News: 669 abstracts evaluated ! 250 orals + 45 ignite talks selected and participants notified ICHA 2018 News: 669 abstracts evaluated ! 9 plenaries confirmed 250 orals + 45 ignite talks selected and participants notified 3 satellite sessions 9 plenaries confirmed 3 satellite sessions