Toxins shellfish

Figure 6. Fluorometric HPLC of diarrhetic shellfish toxins A, AM (9-anthrylmethyl) esters of constituents which have a carboxylic acid column, Develosil ODS (Nomura Chem.) solvents, CH3CN-CH3OH-H2O (8 1 1) monitor ex. 365, em. 412 nm and B, AN (anthroyl) esters of PTXl and PTX4 column and solvents were the same as those in A monitor x. 365, em. 465.

Valuable contributions were made by two Canadian agencies, particularly by the National Research Council Canada (NRCC) who, from about 1976, provided marine and marine biological CRMs certified for metals, metal species and organic constituents (Berman 1984 Willie 1997). More recently their Halifax laboratories have issued a highly respected range of CRMs for the determination of shellfish toxins. Another Canadian producer, the National Water Research Institute (NWRI) specialized in marine (water and sedimentary) CRMs, and from the late 1980 s their matrix materials certified also for organic compounds (Chau et al. 1979 Lee and Chau 1987). 

Anabaena Yes Anatoxin-a Anatoxin-a(S) Microcystins Paralytic shellfish toxins... 

Cyanobacterial neurotoxins are small ringed alkaloids and have dramatic effects on various components of vertebrate neurons. They are all water soluble and are synthesized by several cyanobacterial genera (Table 5.1). The most commonly isolated neurotoxins are the paralytic shellfish toxins, although several other potent neurotoxic alkaloids are synthesized by freshwater cyanobacteria (Table 5.1). 

The paralytic shellfish toxins (PSTs Fig. 5.2a) include saxitoxin (STX) as well as STX analogs such as neo-saxitoxin (neo-STX), gonyautoxin (GTX), and the decar-bamoyltoxins (Sivonen and Jones 1999). These molecules are of particular concern in marine systems, where they have been implicated in human deaths following the consumption of contaminated seafood (Van Dolah 2000). The causative agents in those cases are several genera of marine dinoflagellates that are common components of red tides (e.g., Alexandrium sp. Homer et al. 1997 Van Dolah 2000). 

Denise LeBlanc is the Group Leader for the Marine Sciences Group and the Manager of the Certified Reference Materials Program at the Institute for Marine Biosciences (IMB) of the National Research Council of Canada. The Certified Reference Materials Program manufactures instrument calibration standards and certified reference materials for shellfish toxins, PCBs, PACs, and trace elements in marine sediments, in biological tissues, and in seawater. Her experience resides in the manufacture and long-term production of reference materials. 

Aune, T. and Yndestad, M., Diarrhetic shellfish poisoning, in Falconer, I.R., ed.. Algal Toxins in Seafood and Drinking Water, Academic Press, San Diego, 1993. Australia New Zealand Food Authority, Shellfish Toxins in Food, A Toxicological Review and Risk Assessment, Australia New Zealand Food Authority, Canberra, 2001. 

Kotaki, Y., Oshima, Y. and Yasumoto, T., Analysis of paralytic shellfish toxins in marine snails, Bull. Jpn. Soc. Sci. Fish., 47, 943, 1981. 

Leira, F., et al., Development of a F actin-based live-cell fluorimetric microplate assay for diarrheic shellfish toxins. Anal. Biochem., 317, 2, 129, 2003. 

Raj, U., et al., The occurrence of paralytic shellfish toxins in two species of xanthid crab from Suva barrier reef, Fiji Islands, Toxicon, 21, 4, 547, 1983. 

Glaucous-winged gull Clams Paralytic shellfish toxins Pawlik, 1993 ... 

Figure 9. Shellfish toxin data from Newagen, Maine. Upper panel is times of State closure to the taking of shellfish (>80pg/100g) for years 1972 to 1982. Bottom panel is "start dates" indicating when initial levels over quarantine are witnessed. These dates fall in categories 1) transition from mixed to stratified water column (May) and vice versa (Sept.) and 2) during summer meteorological events.

Table I. Shellfish Toxin Content. Numbers of Marine Shellfish Samples Which Meet Stated Criteria...

HALL AND REICHARDT Cryptic Paralytic Shellfish Toxins... 

Despite the uncertainties in HOP for the toxins, there is reason to suspect that their mouse intraperitoneal potencies (MIP), the ri for the standard mouse bioassay system, do not bear a uniform relationship to them. Early pharmacological work ( ) on the paralytic shellfish toxins was conducted with shellfish extracts. 

Paralytic shellfish toxins in the dinoflagellate ProtogonyauZax =Gonyaulax) spp. and bivalves of temperate waters have been the subjects of extensive studies. In contrast, information on the occurrence of these toxins in tropical waters has been scarce. 

In this paper we summarize our recent findings on paralytic shellfish toxins in tropical waters (8-15) with new assignment of a component previously unreported. It includes the confirmation of paralytic shellfish toxins in the dinoflagellate Pyrodinium bahamense war, aompressa and bivalver exposed to the organism (, with structural elucidation of three components (9,1 ). The detailed analyses of the toxin composition of crabs (11-13) and marine snails (13,14) and confirmation of a calcareous red alga Jania sp. as the primary source of the toxins ( 15) are also described. 

Bioassay. Toxicity of the materials was measured by the standard mouse bioassay for paralytic shellfish toxins and expressed by mouse unit (MU) as defined by the method (16). For testing the low toxin levels of algal specimens, extracts were treated with a charcoal column prior to injection into mice. 

Toxins were extracted with 0.1 N HCl or 75% EtOH acidified to pH 2 and treated with successive columns of charcoal, Bio-Gel P-2 and Bio-Rex 70. Toxins separated by the last column were identified by tic and electrophoresis. Relative abundance of each toxin was determined by monitoring the eluate from Bio-Rex 70 column by mouse assay. A fluorometric paralytic shellfish toxin analyzer was applied to samples which were too small to be followed by mouse assay. Toxins separated by the ion exchange column (Hitachi gel 3011C) were continuously aromatized by tei t-butylhydroperoxide and monitored by the fluorometer (1 ). 

OSHIMA ET AL. Paralytic Shellfish Toxins in Tropical Waters... 

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