Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Shellfish Poisoning”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed1975

Health hazards of bivalve-mollusk ingestion.

Bivalve mollusks (oysters, clans, and mussels) filter large quantities of water unselectively and thereby may concentrate a variety of aquatic contaminants pathogenic for man within edible shellfish viscera. The recognized bacterial disease associated with ingestion of contaminated bivalves include typhoid fever (not presently a public health problem), Vibrio parahemolyticus gastroenteritis, and Vibrio chloerae infection. The major known shellfish-associated viral diseases are viral hepatitis and possibly viral gastroenteritis. The ingestion of bivalves that have fed on the toxic species of dinoflagellates that produce red tides may be responsible for an uncommon and very rarely fatal illness, paralytic shellfish poisoning. Outbreaks of airborne respiratory irritation in populations exposed to red tides may be the most common public health problem associated with red tides. The health hazards resulting from industrial, agricultural, and oil pollution of bivalves in coastal waters and the hazard from improper handling of bacterially contaminated mollusks remain to be defined.

Animals↗
PubMed2003

Paralytic toxins in three new gastropod (Olividae) species implicated in food poisoning in southern Taiwan.

The toxins in the new gastropods Oliva miniacea, O. mustelina and O. nirasei implicated in a food paralytic poisoning incident in South Taiwan in February 2002 were studied. It was found that the three species of gastropods contained moderate amounts of toxin in edible portion only, and the highest toxicity score was 18 MU/g for O. miniacea, 10 MU/g for O. mustelina, and 27 MU/g for O. nirasei. The toxin was partially purified from the toxic specimens of each species by ultrafiltration using a YM-1 membrane, followed by chromatography on Bio-Gel P-2 column. Analyses by HPLC, GC-MS and LC-MS showed that the toxin from O. miniacea, O. nirasei and O. mustelina contained TTX, and related compounds 4-epi TTX and anhydro-TTX. The paralytic shellfish poisons were not found.

Animals↗
PubMed2001

A fluorimetric method based on changes in membrane potential for screening paralytic shellfish toxins in mussels.

To prevent the consumption of bivalves contaminated with paralytic shellfish poisoning (PSP), toxin levels in seafood products are estimated by using the official mouse bioassay. Because of the limitations of this bioassay other methods of monitoring toxins are clearly needed. We have developed a test to screen for PSP toxins based on its functional activity; the toxins bind to the voltage-gated Na+ channels and block their activity. The method is a fluorimetric assay that allows quantitation of the toxins by detecting changes in the membrane potential of human excitable cells. This assay gives an estimate of toxicity, since each toxin present in the sample binds to sodium channels with an affinity which is proportional to its intrinsic toxic potency. The detection limits for paralytic shellfish toxins were found to be 1 ng saxitoxin equivalents/ml compared to the regulatory limit threshold of 400 ng/ml (equivalent to 80 microg/100 g) used in most countries. Our results indicate that this fluorescent assay is a specific, very sensitive, rapid, and reliable method of monitoring PSP toxin levels in samples from seafood products and toxic algae.

Animals↗
PubMed1999

Production and characterization of a monoclonal antibody against domoic acid and its application to enzyme immunoassay.

For production of monoclonal antibodies against domoic acid, a causative agent of amnesic shellfish poisoning, three immunogens, domoic acid conjugated with bovine serum albumin (BSA), ovalbumin (OVA) and human gamma globulin (HGG), were prepared. The antiserum obtained from BALB/c mice immunized with domoic acid-BSA showed the highest affinity for domoic acid. The monoclonal antibody, DA-3, obtained from the mice was highly specific for domoic acid and showed a minor cross-reactivity with the isomers of domoic acid (isodomoic acids B, E, F, G and H), except for isodomoic acid A. Using DA-3 antibody, an indirect competitive enzyme immunoassay (idc-EIA) was developed for measurement of domoic acid. The working range for quantitative measurement of domoic acid and the quantification limit for domoic acid in shellfish were estimated to be 0.15-10 ng/ml and less than 0.04 microg/g, respectively. The mean recovery of domoic acid added to extracts of shellfish at toxin levels of 0.02 to 0.2 microg/ml was 103% with a coefficient of variation of 4.5%. The newly developed idc-EIA seems to be a useful method for monitoring domoic acid in shellfish.

Animals↗
PubMed2001

Structural elucidation of a new cytotoxin isolated from mussels of the Adriatic sea.

A detailed analysis of the toxic composition in the hepatopancreas of mussels from northern Adriatic sea has been performed. Along with some polyether toxins of DSP (diarrhetic shellfish poisoning) type, such as yessotoxin and its analogues, which are responsible for a variety of human seafood poisonings throughout the world, we have now isolated a new type of toxin, the chlorosulfolipid 1, which is completely different in structure from the polyether DSP-toxins isolated so far. The structural determination of the new toxin, including its absolute stereochemistry, has been performed by extensive NMR analysis and molecular mechanics and dynamics calculations.

Animals↗
PubMed1996

Interference of free fatty acids from the hepatopancreas of mussels with the mouse bioassay for shellfish toxins.

Determination of free fatty acids (FFA) in hepatopancreas of mussel, Mytilus coruscus, contaminated by diarrhetic shellfish poisoning (DSP) toxins, was carried out by high-performance liquid chromatography-fluorometry as their 9-anthryldiazomethane derivatives. The FFA in the hepatopancreas of mussels during May 30-June 14 were 443-666 micrograms/g. A marked increase in FFA content was observed on June 20 (2197 micrograms/g hepatopancreas) and June 27 (6322 micrograms/g hepatopancreas). The proportion of polyunsaturated fatty acids (PUFA), including 20:4n-6, 20:5n-3, and 22:6n-3, in mussel FFA increased during the experimental period. Diatoms almost completely dominated the phytoplankton community at the experimental site, suggesting that diatoms were the origin of the PUFA accumulated in mussels. The toxicity of FFA in mussel hepatopancreas on June 27 was sufficiently high as to interfere with the mouse bioassay by injection of an extract of shellfish, the official method for DSP toxin analysis.

Animals↗
PubMed1999

Confirmation of domoic acid production of Pseudo-nitzschia multiseries isolated from Ofunato Bay, Japan.

Production of domoic acid (DA), the responsible toxin for amnesic shellfish poisoning, was examined for 44 strains of Pseudo-nitzschia spp. isolated from Ofunato Bay, Japan. Only one strain which was identified as Pseudo-nitzschia multiseries produced DA in a level comparable to Canadian strains. No significant DA was detected in the rest of the strains, indicating that toxic P. multiseries does not bloom in a high density in the bay.

Canada↗
PubMed2000

Development of a method for the identification of azaspiracid in shellfish by liquid chromatography-tandem mass spectrometry.

Azaspiracid is the main toxin responsible for a number of recent human intoxications in Europe resulting from shellfish consumption. The first micro liquid chromatography-tandem mass spectrometry (micro-LC-MS-MS) method was developed for the determination of this novel shellfish poisoning toxin in mussels. The analyte was extracted from whole mussel meat with acetone and chromatographed on a C18 reversed-phase column (1.0 mm I.D.) by isocratic elution at 30 microl/min with acetonitrile-water (85:15, v/v), containing 0.03% trifluoroacetic acid. The toxin was ionised in an ionspray interface operating in the positive ion mode, where only the intact protonated molecule, [M+H]+, was generated at m/z 842. This served as precursor ion for collision-induced dissociation and three product ions, [M+H-nH2O]- with n=1-3, were identified for the unambiguous toxin confirmation by selected reaction monitoring LC-MS-MS analysis. A detection limit of 20 pg, based on a 3:1 signal-to-noise ratio, was achieved for the analyte. This LC-MS-MS method was successfully applied to determine azaspiracid in toxic cultivated shellfish from two regions of Ireland.

Animals↗
PubMedDate not supplied

Determination of decarbamoyl saxitoxin and its analogues in shellfish by prechromatographic oxidation and liquid chromatography with fluorescence detection.

Oxidation and chromatographic conditions for detecting the decarbamoyl analogues of several paralytic shellfish poison (PSP) toxins were studied. Prechromatographic oxidation with periodate or hydrogen peroxide under slightly alkaline conditions was used as previously reported for the parent PSP toxins. Both periodate and hydrogen peroxide oxidations produced 2 fluorescent products separable by liquid chromatography for each decarbamoyl (dc) toxin (dc-saxitoxin, dc-neosaxatoxin and dc-gonyautoxins 2 and 3). Decarbamoyl saxitoxin produced the same 2 products as did dc-neosaxitoxin but in different ratios. One of these products was the same as the one obtained with neosaxitoxin after periodate oxidation. Decarbamoyl gonyautoxins 2 and 3 (together) produced 2 products, one of which was the same as the major product obtained with gonyautoxins 1 and 4 (together) after periodate oxidation. Decarbamoyl gonyautoxins 1 and 4 were not available for study. The method was used to detect dc-saxitoxin and dc-gonyautoxins 2 and 3 in shellfish extracts.

Animals↗
PubMed2000

Evaluation of 11-[3H]-tetrodotoxin use in a heterologous receptor binding assay for PSP toxins.

This report describes the preparative scale production of 11-[3H]-tetrodotoxin (TTX) and its evaluation as a substitute for [3H]-saxitoxin (STX) as the radioligand in a receptor binding assay for paralytic shellfish poisoning (PSP) toxins. Restrictions on the world-wide distribution of [3H]-STX imposed by the international Chemical Weapons Convention served as the primary impetus for this study. We have incorporated on a preparative scale, a nonexchangeable tritium label into the TTX molecule at a specific activity of 12.90 Ci/mmol and recovered material of high radiochemical purity (98%). The resulting 11-[3H]-TTX was found to exhibit site-specific binding characteristics in the receptor assay (dissociation constant(K(d))=4.77+/-1.54nM; maximum binding(B(max))=1. 62+/-0.24pmol/mg of synaptosomal protein). The inhibition constant (K(i)) for the assay was 1.46+/-0.28 nM STX equiv. (n=6), with an estimated detection limit of ca. 2-4 ng STX equiv./ml in a sample extract. Moreover, quantitative comparisons indicated that 11-[3H]-TTX could be used interchangeably with [3H]-STX in the receptor assay for determination of PSP toxicity in shellfish and algal extracts without compromising assay performance. We conclude that the 11-[3H]-TTX produced and evaluated herein exhibits physical, chemical and biological characteristics suitable not only for use in the PSP receptor binding assay, but likely for other applications employing [3H]-STX as the radioligand.

Evaluation Studies as Topic↗
PubMed1990

Analysis of domoic acid and related compounds by mass spectrometry and gas chromatography/mass spectrometry as N-trifluoroacetyl-O-silyl derivatives.

A method is presented for the analysis of shellfish tissue for domoic acid, a neurotoxic amino acid responsible for cases of amnesic shellfish poisoning. Tissue extracts are first taken through a two-stage solid-phase extraction clean-up, using reversed-phase and strong cation exchange cartridges. A two-stage derivatization, using N-methyl-bis-trifluoroacetamide followed by either N-methyl-tert-butyldimethylsilyltrifluoroacetamide or N, O-bis-trimethylsilyltrifluoroacetamide, is then used to produce an N-trifluoroacetyl-O-silyl derivative which can be analyzed by mass spectrometry with introduction via direct inlet probe, moving-belt liquid chromatograph/mass spectrometer interface, or capillary column gas chromatography. The N-trifluoroacetyl-O-tert-butyldimethylsilyl derivative, which has good stability towards hydrolysis, provides a spectrum well suited to gas chromatography/mass spectrometry (GC/MS) using selected ion recording. GC/MS data for two related compounds, kainic acid and dihydrokainic acid, are also reported. The latter is used as an internal standard for quantification of domoic acid, although the method reported is intended primarily for confirmation of the toxin and related compounds in shellfish tissue.

Chromatography, Gas↗
PubMedDate not supplied

Determination of brevetoxins in shellfish by the neuroblastoma assay.

A neuroblastoma assay for determination of brevetoxins in shellfish was developed together with a method for sample cleanup that allows separation of brevetoxins from most of the components that cause matrix interference in the assay. This improved assay method was applied to a range of shellfish samples with different characteristics. Extracts of naturally contaminated and nontoxic shellfish together with extracts spiked with known amounts of toxin were tested. The results demonstrated that brevetoxins could be reliably detected in shellfish extracts at concentrations below the regulatory limit. Brevetoxin activity was detected in 15 of 23 samples from 5 separate toxicity incidents in which shellfish tested positive in the neurotoxic shellfish poisoning (NSP) mouse bioassay. Twelve of these positive NSP results came from 2 toxicity incidents. Yessotoxin was the major contributor to toxicity in 2 other incidents, although some samples contained both yessotoxin and brevetoxin. The sample from the remaining incident contained an unidentified toxin bioactivity, together with gymnodimine. In contrast to earlier versions of the neuroblastoma assay, gymnodimine was not detected by this modified method.

Animals↗
PubMed2001

PSP toxins from Aphanizomenon flos-aquae (cyanobacteria) collected in the Crestuma-Lever reservoir (Douro river, northern Portugal).

The presence of paralytic shellfish poisoning (PSP) toxins in cultures of Aphanizomenon flos-aquae, isolated from the Crestuma-Lever reservoir, was found by reversed phase high performance liquid chromatography employing two isocratic elution systems for the separation of PSP toxins. With the first isocratic elution protocol, the presence of apolar toxins as saxitoxin, decarbamoyl saxitoxin and neosaxitoxin not detected. On the other hand, GTX4, GTX1 and GTX3 as well as Cs toxins were present either in the Aphanizomenon flos-aquae cells collected directly from the bloom or in the other toxic isolates priorly cultivated in laboratory conditions.

Bacterial Toxins↗
PubMed1996

Liquid chromatographic determination of okadaic acid and dinophysistoxin-1 in shellfish after derivatization with 9-chloromethylanthracene.

The reagent 9-chloromethylanthracene was evaluated for derivatization of the diarrhetic shellfish poisons, okadaic acid and dinophysistoxin-1 (DTX-1), to form fluorescent products separable by liquid chromatography. The toxins were reacted with the reagent in acetonitrile in the presence of tetramethylammonium hydroxide for 1 h at 90 degrees C. The products were purified by using two silica solid-phase extraction cartridges before being determined by reversed-phase liquid chromatography with fluorescence detection. The results are comparable to those obtained using 9-anthryldiazomethane (ADAM) for okadaic acid and DTX-1 in mussel tissue. Detection limits were estimated to be about 70-100 ng/g hepatopancreas (equivalent to 12-20 ng/g whole tissue) for each toxin.

Animals↗
PubMedDate not supplied

The use of Daphnia magna for detection of okadaic acid in mussel extracts.

Okadaic acid (OA), the main toxin responsible for diarrheic shellfish poisoning (DSP) has toxicity for Daphnia magna (EC50 = 15 +/- 1.8 micrograms/l). A Daphnia bioassay was developed and used to analyse okadaic acid in mussel extracts. A linear correlation was found between OA concentration determined by the Daphnia bioassay and by HPLC assay (r = 0.85; p < 0.001). The Daphnia bioassay can measure OA levels 10 times below the threshold of the mouse bioassay method. It is an inexpensive sensitive tool which can be used in replacement of mouse bioassay for the screening of OA and some co-extracting toxins in mussel extracts.

Animals↗
PubMed2001

Decimal reduction times of Pyrodinium bahamense var. compressum and Escherichia coli in chlorine- and ultraviolet-treated seawater.

AIMS: Decimal reduction times (D-values) of the vegetative cells of Pyrodinium bahamense var. compressum and Escherichia coli in ultraviolet- and chlorine-treated seawater were established. METHODS AND RESULTS: The cells of the test organisms were exposed to ultraviolet- and chlorine-treated seawater and maintained at 20-35 ppt salinity and 20 to 35 degrees C. The dinoflagellate cells which cause Paralytic Shellfish Poisoning (PSP) were found to be more resilient than the bacterial cells. Ultraviolet treatment was found to be more effective than chlorine to both test organisms. Irreversible morphological changes in the treated dinoflagellate cells were noted, including protoplast discoloration, cellular membrane leakage and damage to the thecal armour. CONCLUSIONS: The vegetative cells of both test organisms in seawater were more sensitive to ultraviolet treatment than to chlorine exposure. Generally, the dinoflagellate cells were less susceptible than bacterial cells to both disinfection treatments. SIGNIFICANCE AND IMPACT OF THE STUDY: Results of this study may have significant implications in depuration procedures for molluscs and cleaning protocols for ballast waters of ships.

Animals↗
PubMed1991

Light and scanning electron microscopic studies on effects of marine algal toxins toward freshly prepared hepatocytes.

Mussels exposed to dinoflagellates may represent a human health risk due to accumulation of a variety of algal toxins. In several parts of the world, algal toxins leading to diarrhea (diarrhetic shellfish poisons, DSP) are found in mussels for extended periods of the year. Routine monitoring of these toxins involves ip injections in mice. Chemical analytical methods have been developed for only some of the toxins in question, namely, those giving diarrhea. Other toxins in the DSP complex are not easily detected by analytical methods. In this report we show that freshly prepared hepatocytes from rats are a convenient means to differentiate between the toxins that give diarrhea and those that do not. Consequently, hepatocytes can be useful in both screening and as a tool in the process of developing analytical methods. Freshly prepared hepatocytes might be useful in combination either with the mouse bioassay or with chemical analytical methods.

Animals↗
PubMed1994

Effects of nitrogen concentration and cold temperature on DSP-toxin concentrations in the dinoflagellate Prorocentrum lima (Prorocentrales, Dinophyceae).

The diarrhetic shellfish poisoning toxin-producing dinoflagellate, Prorocentrum lima, isolated from Nova Scotian waters, contained both okadaic acid (OA) and dinophysistoxin-1 (DTX-1) throughout its growth cycle in culture; maximum concentrations of toxins and highest OA/DTX-1 ratios occurred during the stationary phase. Cells of P. lima survived 0 degrees C for 5 weeks and recovered when brought to a higher temperature. During the cold period, some cell damage probably occurred with concomitant losses of toxins to the medium. Nitrogen concentration in the medium was used to limit growth or stress the cells physiologically, and when growth was limited, increases in toxin associated with the cells were recorded. The relative amounts of okadaic acid were always greater than dinophysistoxin-1, but the significance of these ratios remains to be determined.

Animals↗