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THE MICROCYSTIN GROUP OF CYANOTOXINS: STRUCTURE, OCCURRENCE, MONITORING AND MANAGEMENT OPTIONS AND THE DEVELOPMENT OF HU

Types of Harmful Algal Blooms. Produce dense blooms leading to oxygen stress.DinoflagellatesCyanobacteria (prokaryotic microbes)Produce potent toxins

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THE MICROCYSTIN GROUP OF CYANOTOXINS: STRUCTURE, OCCURRENCE, MONITORING AND MANAGEMENT OPTIONS AND THE DEVELOPMENT OF HU

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    1. THE MICROCYSTIN GROUP OF CYANOTOXINS: STRUCTURE, OCCURRENCE, MONITORING AND MANAGEMENT OPTIONS AND THE DEVELOPMENT OF HUMAN RISK ASSESSMENT MODELS

    2. Types of Harmful Algal Blooms Produce dense blooms leading to oxygen stress. Dinoflagellates Cyanobacteria (prokaryotic microbes) Produce potent toxins—illness and death via food chain or biomass accumulation. Paralytic shellfish poisoning (PSP) Diarrheal shellfish poisoning (DSP) Neurotoxic shellfish poisoning (NSP) Ciguatera fishfood poisoning (CFP) Estuary-associated syndrome (EAS)

    3. HAB Legislation U.S. Harmful Algal Bloom Eradication and Control Act of 1998-Subcommittee on Oceans and Fisheries-U.S. Senate Harmful Algae Bloom and Hypoxia Research Amendment Act of 2003-Subcommittee on Environment, Technology and Standards-U.S. House of Representatives Committee on Science (includes study of CyanoHABs in navigatable waters-i.e. Lake Erie) National Plan for Algal Toxins and Harmful Algal Blooms - March 21-25, 2004 Workshop-Charleston, SC-NOAA

    9. Cyanotoxins— Mode of Action Neurotoxins Hepatotoxins Dermatoxins

    10. Cyanotoxins— Target Organisms Location Water Environment Water Users Organisms Wild Birds & Fish Wild Invertebrates Aquacultured Fish and Invertebrates Domestic & Wild Animals Humans Agriculture (Plants)

    12. Lyngbya wollei

    14. By Wayne Carmichael January 2004

    15. CyanoHAB Search evolved from 30 years of studies of toxic blue-green algae, and contains 3,063 references citing 705 journals written by 4,687 authors and editors. The database is comprised of toxic cyanobacteria references in an electronic format (ProCite®) that can be searched, sorted and listed by author, year, title, reference source or subject.

    17. 1996 Safe Drinking Water Act Amendments Authorizes regulation of contaminants in drinking water Establishes procedure for making regulatory decisions Requires at least 5 contaminants to be considered every 5 years

    19. CCL2 Microorganisms Adenoviruses Aeromonas Caliciviruses Coxsackieviruses Cyanobacteria and their toxins Echoviruses Helicobacter pylori Microsporidia Mycobacterium avium complex

    20. Priority Listing of Cyanotoxins for Action Microcystins-Analytical standards, rapid detection and setting of guideline values Cylindrospermopsins- Analytical standards, rapid detection and setting of guideline values Anatoxin-a- Analytical standards, rapid detection and setting of guideline values Saxitoxins, Nodularins, LPS-Secondary priority-pending further evaluation of occurrence in freshwaters

    21. Etiologic agents associated with drinking water outbreaks, by water type – United States, 1989-2000 (n = 175)

    22. Cyanotoxin Analyses Methods Biological - Bioassay Small animal-mouse, invertebrate LD and LC50 Microbial Biochemical-i.e. Immunological (ELISA); Enzyme (PPIA); Cell Receptor Analytical- HPLC, MS, NMR Genetic-PCR

    25. LC/MS Analysis of Cyanotoxins

    26. ESIMS Fragment Ions for a Typical Liver Analyses of Microcystins

    29. Genetic Studies Genetic - PCR 16S rRNA nifH (gene for dinitrogen reductase-N2 fixation) cpcBA-IGS (intergenic spacer region between two phycobilisome subunits) MCY (microcystin gene) Other toxin genes (CYN, Antx-a) are being studied

    30. Examples of Applications for Methods Developed Migratory Waterfowl Deaths Aquacultured Fish Losses Aquacultured Invertebrates Analyses of Human Serum and Tissue Great Lakes CyanoHABs Lesser Flamingos-Africa Dog Deaths - Nebraska

    35. Australian Publications Australian Drinking Water Guidelines-1996-National Health and Medical Research Council (NHMRC) Evaluation of Analyt Meth Detect & Quant Cyanotoxins in Rel to Aust Drinking Water Guidelines-2001-NHMRC Guidelines for Managing Risks in Recreational Water-2004-NHMRC (Draft) Management Strategies for Toxic Blue-Green Algae: Literature Review. Aust. W.Q.C. House et al. 2004. Water Treatment Options for Dissolved Cyanotoxins. Aqua. 53:229-239. 2004

    38. WHO Provisional Guideline MCYST-LR (1998) Based upon two animal studies: 1) Mouse oral NOAEL = 40 µg/kg bw/day UF = 1000 (10x for intraspecies; 10x for interspecies; 10x for limited database) TDI = 0.04 µg/kg bw/day 2) Pig oral LOAEL = 100 µg*/kg bw/day UF = 1500 (10x for intraspecies; 3x for interspecies; 5x for extrapolating LOAEL to NOAEL;10x for less than lifetime exposure) TDI = 0.067 µg/kg bw/day

    39. WHO Provisional Guideline (continued) Using TDI = 0.04 µg/kg bw/day Guideline value = TDI x bw x P L bw = 60 kg (70 kg Australia)* P = 0.8 (0.9 Australia)* L = 2 L/day * Results in 1.3 µg/L

    40. Acknowledgements U.S. - EPA James Sinclair Betsy Hilborn Florida (Funding sources) FMRI SJWMD through FMRI Wright State Univ. John Blakelock Laurel Carmichael Jeanette Frey Charles Friday Jennifer Ott Jerome Servaites Mary Stukenberg Moucun Yuan AwwaRF CDC-Atlanta CRC for Water Quality and Treatment-Adelaide UNC-IMS Hans Paerl and crew Canada E.A.D. Allen Univ. Illinois-NIH Ken Rinehart Robert Coates Queensland Health-EnTox Glen Shaw Geoff Eaglesham

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