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Sample records for shellfish geukensia demissa

  1. Predation of the ribbed mussel geukensia demissa by the blue crab callinectes sapidus

    NASA Astrophysics Data System (ADS)

    Seed, R.

    Callinectes sapidus fed extensively on Geukensia demissa in laboratory aquaria. Several predation techniques used by Callinectes to open its prey are reported. Prey value decreases monotonically with increasing mussel size. Crabs consumed mussels over a wide size range but were generally reluctant to feed on larger mussels whilst smaller, more profitably prey was available. The relative importance of 'energy maximization' and 'time minimization' could not be distinguished. The distribution and population structure of Geukensia at Beaufort, N. Carolina are briefly considered in terms of the foraging strategy of Callinectes.

  2. The introduced ribbed mussel (Geukensia demissa) in Estero de Punta Banda, Mexico: Interactions with the native cord grass, Spartina foliosa

    USGS Publications Warehouse

    Torchin, M.E.; Hechinger, R.F.; Huspeni, T.C.; Whitney, K.L.; Lafferty, K.D.

    2005-01-01

    Introduced populations of Guekensia demissa occur on the west coast of North America. They have been reported in San Francisco Bay, four southern California wetlands, and in Estero de Punta Banda (EPB), Baja California Norte, Mexico. We randomly sampled benthic invertebrates in four habitat types within EPB: marsh, channel, mudflat and pan. Geukensia demissa was the most abundant bivalve in the wetland at EPB. It was significantly associated with the native cordgrass, Spartina foliosa, and occurred at higher average densities in vegetated marsh sites (24/m2) and Spartina-dominated tidal channels (35/m2), compared to mudflat (0/m2), and pan (0/m 2) sites. We estimated that the total biomass of this invader was over four times that of the next most abundant bivalve, Tagelus spp., in EPB. We examined G. demissa for parasites and found that only a few native parasites colonized this introduced host at very low prevalences and intensities. We performed bird surveys to determine the habitat overlap and potential impact of this mussel on the EPB population of light-footed clapper rails (Rallus longirostrus levipes), an endangered species in the United States. The high abundance of G. demissa in EPB, its presence in clapper rail habitat, and its known effects on salt marsh habitat in it's native range, warrant further investigations of the impact of this invader in EPB and elsewhere. ?? Springer 2005.

  3. Changes in protein expression in the salt marsh mussel Geukensia demissa: evidence for a shift from anaerobic to aerobic metabolism during prolonged aerial exposure

    PubMed Central

    Fields, Peter A.; Eurich, Chris; Gao, William L.; Cela, Bekim

    2014-01-01

    During aerial exposure (emersion), most sessile intertidal invertebrates experience cellular stress caused by hypoxia, and the amount and types of hypoxia-induced stress will differ as exposure time increases, likely leading to altered metabolic responses. We examined proteomic responses to increasing emersion times and decreasing recovery (immersion) times in the mussel Geukensia demissa, which occurs in salt marshes along the east coast of North America. Individuals are found above mean tide level, and can be emersed for over 18 h during spring tides. We acclimated mussels to full immersion at 15°C for 4 weeks, and compared changes in gill protein expression between groups of mussels that were continually immersed (control), were emersed for 6 h and immersed during recovery for 18 h (6E/18R), were emersed for 12 h and recovered for 12 h (12E/12R), or were emersed for 18 h with a 6 h recovery (18E/6R). We found clear differences in protein expression patterns among the treatments. Proteins associated with anaerobic fermentation increased in abundance in 6E/18R but not in 12E/12R or 18E/6R. Increases in oxidative stress proteins were most apparent in 12E/12R, and in 18E/6R changes in cytoskeletal protein expression predominated. We conclude that G. demissa alters its strategy for coping with emersion stress over time, relying on anaerobic metabolism for short- to medium-duration exposure, but switching to an air-gaping strategy for long-term exposure, which reduces hypoxia stress but may cause structural damage to gill tissue. PMID:24501137

  4. Chemical and ancillary data associated with bed sediment, young of year Bluefish (Pomatomus saltatrix) tissue, and mussel (Mytilus edulis and Geukensia demissa) tissue collected after Hurricane Sandy in bays and estuaries of New Jersey and New York, 2013–14

    USGS Publications Warehouse

    Smalling, Kelly L.; Deshpande, Ashok D.; Blazer, Vicki; Galbraith, Heather S.; Dockum, Bruce W.; Romanok, Kristin M.; Colella, Kaitlyn; Deetz, Anna C.; Fisher, Irene J.; Imbrigiotta, Thomas E.; Sharack, Beth; Summer, Lisa; Timmons, DeMond; Trainor, John J.; Wieczorek, Daniel; Samson, Jennifer; Reilly, Timothy J.; Focazio, Michael J.

    2015-01-01

    Twenty three PCB congeners, 9 PBDE congeners, and 20 OCPs were detected in composite mussel samples collected throughout the study area. The co-eluting PCB congeners 153 and 132, PBDE 47, 99, and 100, and p,p’-DDE were detected in samples from each site. The highest median concentrations of PCBs and PBDEs were present in mussels from Raritan Bay, N.Y., whereas the highest median concentrations of OCPs were present in mussels from Fire Island Inlet, N.Y., and Shark River, N.J. Mytilus edulis (blue mussels) and Geukensia demissa (ribbed mussels) were thin-sectioned and aged. The blue mussels collected ranged in age from 4 to 13 years, and the ribbed mussels ranged in age from 3 to 12 years.

  5. Shellfish Allergy

    MedlinePlus

    ... The two different types of shellfish allergy are: crustaceans (like shrimp, crab, or lobster) mollusks (like clams, ... of the top eight most common allergens, including crustacean shellfish. The label should list "shellfish" in the ...

  6. Shellfish Allergy

    MedlinePlus

    ... fish allergy. Shellfish fall into two different groups: crustaceans (like shrimp, crab, or lobster) and mollusks (like ... shellfish on food labels, they are referring to crustacean shellfish. If you are allergic to mollusks, then ...

  7. Shellfish Allergy

    MedlinePlus

    ... specific shellfish used on the label. Read all product labels carefully before purchasing and consuming any item. Ingredients ... and may not be fully disclosed on a product label. Your doctor may advise you to avoid mollusks ...

  8. Shellfish contamination and spoilage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molluscan shellfish are prone to contamination by fecal and vibrio bacteria, fecal viruses, biotoxins, and chemical pollutants. In this book chapter, the problems and challenges for the shellfish industry are described and discussed. Basic regulatory frameworks, management strategies, critical cont...

  9. Shellfish allergy in children.

    PubMed

    Kandyil, Roshni M; Davis, Carla M

    2009-08-01

    Food allergies affect approximately 3.5-4.0% of the world's population and can range from a mere inconvenience to a life-threatening condition. Over 90% of food allergies in childhood are caused by eight foods: cow's milk, hen's egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. Shellfish allergy is known to be common and persistent in adults, and is an important cause of food induced anaphylaxis around the world for both children and adults. Most shellfish-allergic children have sensitivity to dust mite and cockroach allergens. Diagnostic cut-off levels for skin prick testing in children with shrimp allergy exist but there are no diagnostic serum-specific immunoglobulin E (IgE) values. All patients with symptoms of IgE-mediated reactions to shellfish should receive epinephrine autoinjectors, even if the initial symptoms are mild. In this study, we review three cases of clinical presentations of shellfish allergy in children. PMID:19674349

  10. Poisoning - fish and shellfish

    MedlinePlus

    Fish poisoning; Dinoflagellate poisoning; Seafood contamination; Paralytic shellfish poisoning; Ciguatera poisoning ... algae and algae-like organisms called dinoflagellates. Small fish that eat the algae become contaminated. If larger ...

  11. Neurotoxic shellfish poisoning.

    PubMed

    Watkins, Sharon M; Reich, Andrew; Fleming, Lora E; Hammond, Roberta

    2008-01-01

    Neurotoxic shellfish poisoning (NSP) is caused by consumption of molluscan shellfish contaminated with brevetoxins primarily produced by the dinoflagellate, Karenia brevis. Blooms of K. brevis, called Florida red tide, occur frequently along the Gulf of Mexico. Many shellfish beds in the US (and other nations) are routinely monitored for presence of K. brevis and other brevetoxin-producing organisms. As a result, few NSP cases are reported annually from the US. However, infrequent larger outbreaks do occur. Cases are usually associated with recreationally-harvested shellfish collected during or post red tide blooms. Brevetoxins are neurotoxins which activate voltage-sensitive sodium channels causing sodium influx and nerve membrane depolarization. No fatalities have been reported, but hospitalizations occur. NSP involves a cluster of gastrointestinal and neurological symptoms: nausea and vomiting, paresthesias of the mouth, lips and tongue as well as distal paresthesias, ataxia, slurred speech and dizziness. Neurological symptoms can progress to partial paralysis; respiratory distress has been recorded. Recent research has implicated new species of harmful algal bloom organisms which produce brevetoxins, identified additional marine species which accumulate brevetoxins, and has provided additional information on the toxicity and analysis of brevetoxins. A review of the known epidemiology and recommendations for improved NSP prevention are presented. PMID:19005578

  12. Neurotoxic Shellfish Poisoning

    PubMed Central

    Watkins, Sharon M.; Reich, Andrew; Fleming, Lora E.; Hammond, Roberta

    2008-01-01

    Neurotoxic shellfish poisoning (NSP) is caused by consumption of molluscan shellfish contaminated with brevetoxins primarily produced by the dinoflagellate, Karenia brevis. Blooms of K. brevis, called Florida red tide, occur frequently along the Gulf of Mexico. Many shellfish beds in the US (and other nations) are routinely monitored for presence of K. brevis and other brevetoxin-producing organisms. As a result, few NSP cases are reported annually from the US. However, infrequent larger outbreaks do occur. Cases are usually associated with recreationally-harvested shellfish collected during or post red tide blooms. Brevetoxins are neurotoxins which activate voltage-sensitive sodium channels causing sodium influx and nerve membrane depolarization. No fatalities have been reported, but hospitalizations occur. NSP involves a cluster of gastrointestinal and neurological symptoms: nausea and vomiting, paresthesias of the mouth, lips and tongue as well as distal paresthesias, ataxia, slurred speech and dizziness. Neurological symptoms can progress to partial paralysis; respiratory distress has been recorded. Recent research has implicated new species of harmful algal bloom organisms which produce brevetoxins, identified additional marine species which accumulate brevetoxins, and has provided additional information on the toxicity and analysis of brevetoxins. A review of the known epidemiology and recommendations for improved NSP prevention are presented. PMID:19005578

  13. The Influence of Feral Horse Activity on Water and Shellfish (Gukensia demissa) Quality Along the Western Coast of Assateague Island National Seashore, Maryland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feral horses (Equus caballus) inhabit portions of the Western United States and some barrier islands along the East Coast. Approximately 150 feral horses are located on Assateague Island National Seashore (ASIS), Maryland, a barrier island popular with tourists and recreational fishermen. This stu...

  14. Effects of low and high salinity regimes on seasonal gametogenesis of the ribbed mussel Geukensia granosissima in coastal Louisiana, USA

    USGS Publications Warehouse

    Honig, Aaron; LaPeyre, Megan K.; Supan, John

    2014-01-01

    Benthic intertidal bivalves play an essential role in estuarine ecosystems by contributing to habitat provision, water filtration, and host vegetation productivity. As such, ecosystem level changes that impact population distributions and persistence of local bivalve populations may have large ecosystem level consequences, making it important to better understand the population ecology of native bivalves. In order to determine potential impacts of shifting salinity and temperature regimes along the northern Gulf of Mexico, the seasonal timing of gametogenesis in the Gulf estuarine ribbed mussel, Geukensia granossisima, was examined across a salinity gradient in southeastern Louisiana, from July 2011 through October 2012. Ten mussels were randomly sampled monthly from low (~ 5) and high (~25) salinity marsh sites in southeastern Louisiana, and histologically processed to determine the seasonal progression of gametogenesis. Peak ripeness occurred at both sites between April and September, was positively correlated with temperature, and coincided with seasonal shifts in salinity. Mussels located in lower salinity waters demonstrated a shorter period of gametogenesis, and lower rates of ripeness indicating that changes in salinity regimes may impact long-term population dynamics.

  15. Bacterial enteropathogens in Malaysian shellfish.

    PubMed

    Jegathesan, M; Wah, L T; Soon, L E; Su Har, D; Boo Liat, L

    1976-06-01

    Three species of commonly eaten shellfish found in Malaysian coastal waters were examined for the presence of common bacterial enteropathogens. Vibrio parahaemolyticus, non-agglutinating vibrios, and various serotypes of enteropathogenic E. coli were isolated from a large proportion of them. Salmonella were isolated in two instances. High colony counts with evidence of faecal contamination indicated the strong possibility of pulltion being the cause for the presence of these enteropathogens. Methods of cooking and eating these shellfish enhance their likelihood of acting as vehicles of diarrhoeal disease. PMID:788266

  16. Risk assessment of shellfish toxins.

    PubMed

    Munday, Rex; Reeve, John

    2013-11-01

    Complex secondary metabolites, some of which are highly toxic to mammals, are produced by many marine organisms. Some of these organisms are important food sources for marine animals and, when ingested, the toxins that they produce may be absorbed and stored in the tissues of the predators, which then become toxic to animals higher up the food chain. This is a particular problem with shellfish, and many cases of poisoning are reported in shellfish consumers each year. At present, there is no practicable means of preventing uptake of the toxins by shellfish or of removing them after harvesting. Assessment of the risk posed by such toxins is therefore required in order to determine levels that are unlikely to cause adverse effects in humans and to permit the establishment of regulatory limits in shellfish for human consumption. In the present review, the basic principles of risk assessment are described, and the progress made toward robust risk assessment of seafood toxins is discussed. While good progress has been made, it is clear that further toxicological studies are required before this goal is fully achieved. PMID:24226039

  17. Risk Assessment of Shellfish Toxins

    PubMed Central

    Munday, Rex; Reeve, John

    2013-01-01

    Complex secondary metabolites, some of which are highly toxic to mammals, are produced by many marine organisms. Some of these organisms are important food sources for marine animals and, when ingested, the toxins that they produce may be absorbed and stored in the tissues of the predators, which then become toxic to animals higher up the food chain. This is a particular problem with shellfish, and many cases of poisoning are reported in shellfish consumers each year. At present, there is no practicable means of preventing uptake of the toxins by shellfish or of removing them after harvesting. Assessment of the risk posed by such toxins is therefore required in order to determine levels that are unlikely to cause adverse effects in humans and to permit the establishment of regulatory limits in shellfish for human consumption. In the present review, the basic principles of risk assessment are described, and the progress made toward robust risk assessment of seafood toxins is discussed. While good progress has been made, it is clear that further toxicological studies are required before this goal is fully achieved. PMID:24226039

  18. [Research Progress in Norovirus Bioaccumulation in Shellfish].

    PubMed

    Zhou, Deqing; Su, Laijin; Zhao, Feng; Ma, Liping

    2015-05-01

    Noroviruses (NoVs) are one of the most important foodborne viral pathogens worldwide. Shellfish are the most common carriers of NoVs as they can concentrate and accumulate large amounts of the virus through filter feeding from seawater. Shellfish may selectively accumulate NoVs with different genotypes, and this bioaccumulation may depend on the season and location. Our previous studies found various histo-blood group antigens (HBGAs) in shellfish tissues. While HBGAs might be the main reason that NoVs are accumulated in shellfish, the detailed mechanism behind NoV concentration and bioaccumulation in shellfish is not clear. Here we review current research into NoV bioaccumulation, tissue distribution, seasonal variation, and binding mechanism in shellfish. This paper may provide insight into controlling NoV transmission and decreasing the risks associated with shellfish consumption. PMID:26470540

  19. 7 CFR 60.133 - Wild fish and shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Wild fish and shellfish. 60.133 Section 60.133... FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and shellfish means naturally-born or hatchery-originated fish or shellfish released in the wild, and...

  20. 7 CFR 60.133 - Wild fish and shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Wild fish and shellfish. 60.133 Section 60.133... FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and shellfish means naturally-born or hatchery-originated fish or shellfish released in the wild, and...

  1. 7 CFR 60.133 - Wild fish and shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Wild fish and shellfish. 60.133 Section 60.133... FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and shellfish means naturally-born or hatchery-originated fish or shellfish released in the wild, and...

  2. 7 CFR 60.133 - Wild fish and shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Wild fish and shellfish. 60.133 Section 60.133... FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and shellfish means naturally-born or hatchery-originated fish or shellfish released in the wild, and...

  3. Biomarkers of neurotoxic shellfish poisoning.

    PubMed

    Abraham, Ann; Plakas, Steven M; Flewelling, Leanne J; El Said, Kathleen R; Jester, Edward L E; Granade, Hudson R; White, Kevin D; Dickey, Robert W

    2008-08-01

    Urine specimens from patients diagnosed with neurotoxic shellfish poisoning (NSP) were examined for biomarkers of brevetoxin intoxication. Brevetoxins were concentrated from urine by using solid-phase extraction (SPE), and analyzed by enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine extracts were fractionated by LC, and fractions analyzed for brevetoxins by ELISA. In subsequent LC-MS/MS analyses, several brevetoxin metabolites of B-type backbone were identified, with elution profiles consistent with those of ELISA. The more abundant brevetoxin metabolites in urine were characterized structurally by LC-MS/MS. With the exception of BTX-3, brevetoxin metabolites in urine differed from those found in shellfish and in shellfish meal remnants. Proposed structures of these major urinary metabolites are methylsulfoxy BTX-3, 27-epoxy BTX-3, and reduced BTX-B5. BTX-3 was found in all specimens examined. BTX-3 concentrations in urine, as determined by LC-MS/MS, correlated well with composite toxin measurements by ELISA (r(2)=0.96). BTX-3 is a useful biomarker for confirmation of clinical diagnosis of NSP. PMID:18582487

  4. Should I Be Concerned about Eating Fish and Shellfish?

    MedlinePlus

    ... Mercury in Fish and Shellfish The Interstate Shellfish Sanitation Conference (ISSC) was formed in 1982 to foster and promote shellfish sanitation through the cooperation of state and federal control ...

  5. Enteric virus and vibrio contamination of shellfish: intervention strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    INTRODUCTION. Molluscan shellfish include oysters, clams, mussels, and cockles, which can cause illnesses from a variety of human pathogens. Enteric viruses, like norovirus and hepatitis A virus, are generally transmitted to shellfish through fecal contamination of shellfish harvesting areas, alth...

  6. Diarrhetic shellfish poisoning, Washington, USA, 2011.

    PubMed

    Lloyd, Jennifer K; Duchin, Jeffrey S; Borchert, Jerry; Quintana, Harold Flores; Robertson, Alison

    2013-08-01

    Diarrhetic shellfish poisoning is a gastrointestinal illness caused by consumption of bivalves contaminated with dinophysistoxins. We report an illness cluster in the United States in which toxins were confirmed in shellfish from a commercial harvest area, leading to product recall. Ongoing surveillance is needed to prevent similar illness outbreaks. PMID:23876232

  7. Detection of enteric viruses in shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Norovirus and hepatitis A virus contamination are significant threats to the safety of shellfish and other foods. Methods for the extraction and assay of these viruses from shellfish are complex, time consuming, and technically challenging. Here, we itemize some of the salient points in extracting...

  8. Fish and Shellfish Associated Disease Outbreaks.

    ERIC Educational Resources Information Center

    Levin, M.

    1978-01-01

    Presents a literature review of disease outbreaks related to fish and shellfish, covering publications of 1976-77. This review covers the chemical, bacterial, and viral diseases that are transmitted by fish and shellfish. A list of 50 references is also presented. (HM)

  9. Fish and shellfish upgrading, traceability.

    PubMed

    Guérard, Fabienne; Sellos, Daniel; Le Gal, Yves

    2005-01-01

    Recognition of the limited biological resources and the increasing environmental pollution has emphasised the need for better utilisation of by-products from the fisheries. Currently, the seafood industry is dependent on the processing of the few selected fish and shellfish species that are highly popular with consumers but, from economic and nutritional points of view, it is essential to utilise the entire catch. In this review, we will focus on recent developments and innovations in the field of underutilised marine species and marine by-product upgrading and, more precisely, on two aspects of the bioconversion of wastes from marine organisms, i.e. extraction of enzymes and preparation of protein hydrolysates. We will deal with the question of accurate determination of fish species at the various steps of processing. Methods of genetic identification applicable to fresh fish samples and to derived products will be described. PMID:16566090

  10. Red Tide and Paralytic Shellfish Poisoning

    ERIC Educational Resources Information Center

    Dale, Barrie; Yentsch, Clarice M.

    1978-01-01

    Discusses the nature and cause of paralytic shellfish poisoning (PSP). Includes toxic dinoflagellate ecology, taxonomy and life history, and chemistry of the toxins. Recent work with trace metals and directions of future research are also given. (MA)

  11. Not all shellfish "allergy" is allergy!

    PubMed Central

    2011-01-01

    The popularity of shellfish has been increasing worldwide, with a consequent increase in adverse reactions that can be allergic or toxic. The approximate prevalence of shellfish allergy is estimated at 0.5-2.5% of the general population, depending on degree of consumption by age and geographic regions. The manifestations of shellfish allergy vary widely, but it tends to be more severe than most other food allergens. Tropomyosin is the major allergen and is responsible for cross-reactivity between members of the shellfish family, particularly among the crustacea. Newly described allergens and subtle differences in the structures of tropomyosin between different species of shellfish could account for the discrepancy between in vitro cross-antigenicity and clinical cross-allergenicity. The diagnosis requires a thorough medical history supported by skin testing or measurement of specific IgE level, and confirmed by appropriate oral challenge testing unless the reaction was life-threatening. Management of shellfish allergy is basically strict elimination, which in highly allergic subjects may include avoidance of touching or smelling and the availability of self-administered epinephrine. Specific immunotherapy is not currently available and requires the development of safe and effective protocols. PMID:22410209

  12. [Nutritive value of shellfish consumed in Chile].

    PubMed

    Pak, N; Vera, G; Araya, H

    1985-03-01

    The purpose of the present study was to determine the protein quality and digestibility of shellfish commonly consumed in Chile, and to estimate its contribution to the protein needs of the Chilean population. The shellfish studied were chorito (Mytilus edulis chilensis), macha (Mesodesma donacium), loco (Concholepas concholepas), cholga (Aulacomya ater), erizo (Loxechinus albus) and almeja (no specific variety). The NPU method was used to determine protein quality. The percentage of protein adequacy for adult rations was calculated according to FAO/WHO 1973. The contribution of shellfish to the protein availability according to the family income of the Santiago population, was also calculated. Most of the shellfish presented NPU values of about 70; the lowest values were found for loco (54.9) and macha (63.3). The apparent and true digestibility gave an average of 83.6 and 90.4, respectively. The percentage of protein adequacy of habitual rations ranged between 27% (erizo) and 58% (loco). The availability of shellfish protein in relation to total protein increased from 0.4 to 2.5% when income increased. It is concluded therefore, that shellfish protein is, in general, of good quality. Nevertheless, it might be considered of poor influence insofar as fulfilling the protein needs of the population studied, whatever its socioeconomic level. PMID:3834878

  13. A Potential Mechanism of Virus Persistence within Bivalve Shellfish.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The process of enteric virus bioaccumulation by molluscan shellfish has been widely studied and documented. However, it is not understood why some human enteric viruses, which cannot replicate within shellfish, are selectively retained and remain viable within shellfish tissues for extended periods...

  14. 21 CFR 1240.60 - Molluscan shellfish.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Molluscan shellfish. 1240.60 Section 1240.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION CONTROL OF COMMUNICABLE DISEASES Specific Administrative...

  15. THE EVOLUTION OF MOLLUSCAN SHELLFISH SAFETY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molluscan shellfish represent one of the few animals frequently eaten raw or only lightly cooked. Since they are filter feeders, able to concentrate contaminants from the water within their edible tissues, they have been widely associated with outbreaks of illness. Heavy metals, petroleum hydrocar...

  16. Shellfish and public health: a Swedish perspective.

    PubMed

    Rehnstam-Holm, Ann-Sofi; Hernroth, Bodil

    2005-03-01

    Bivalves are ancient animals that feed by filtering large volumes of water. In this way, phytoplankton, bacteria and viruses from the water column are greatly concentrated in the mussels. The hazards associated with the consumption of mussels are thus dependent on the occurrence and composition of toxic algae and human microbial pathogens in the areas where shellfish are grown. Diarrheic shellfish toxins have occurred regularly in Sweden during the past 27 years. Peaks of toxins in mussels are mostly recorded from October to December, but the pattern can differ significantly due to location and year, making it hard to predict toxin levels in mussels. With an expansion of aquaculture and a subsequent increase in seafood consumption, better risk management is needed to minimize the effects on humans of algal toxins and human pathogens. New control strategies that have to be implemented are: i) proper site selection of culture installations; ii) regular and cost-efficient monitoring of algae, bacteria and viruses; iii) new indicators for fecal contamination, suitable for the specific locations where shellfish grow; iv) rapid dissemination of information to the industry and public, including risk assessment and advice on how to cope with the situation. PMID:15865311

  17. Shellfish and House Dust Mite Allergies: Is the Link Tropomyosin?

    PubMed

    Wong, Lydia; Huang, Chiung Hui; Lee, Bee Wah

    2016-03-01

    Crustacean shellfish allergy is an important cause of food allergy and anaphylaxis in Asia. The major allergen in shellfish allergy is tropomyosin, a pan-allergen that is also found in house dust mites and cockroaches. Tropomyosins from house dust mites (HDMs) have a high sequence homology to shellfish tropomyosins, and cross-reactivity between HDM and shrimp tropomyosins has been demonstrated. Exposure to inhaled tropomyosins from house dust mites has been postulated to be the primary sensitizer for shellfish allergy, in a reaction analogous to the oral allergy (inhalant-food) syndrome. This notion is supported by indirect data from the effects of HDM immunotherapy on shellfish allergy, and strong correlations of shellfish and HDM sensitization. HDM immunotherapy has been reported to induce both shrimp allergy in non-allergic patients and shrimp tolerance in shrimp-allergic patients. Epidemiological surveys have also demonstrated a strong correlation between shellfish and HDM sensitization in both hospital-based and community-based studies. Unexposed populations have also been shown to develop sensitization-shellfish sensitization in orthodox Jews with no history of shellfish consumption was associated with HDM sensitization. Reciprocally, HDM sensitization in an Icelandic population living in a HDM-free environment was associated with shrimp sensitization. In vitro IgE inhibition studies on sera in shrimp-allergic Spanish patients indicate that mites are the primary sensitizer in shrimp-allergic patients living in humid and warm climates. Current data supports the hypothesis that tropomyosin is the link between HDM and shellfish allergies. The role of tropomyosin in HDM and shellfish allergies is a fertile field for investigation as it may provide novel immunotherapeutic strategies for shellfish allergy. PMID:26739402

  18. Validation Study for Analytical Method of Diarrhetic Shellfish Poisons in 9 Kinds of Shellfish.

    PubMed

    Yamaguchi, Mizuka; Yamaguchi, Takahiro; Kakimoto, Kensaku; Nagayoshi, Haruna; Okihashi, Masahiro; Kajimura, Keiji

    2016-01-01

    A method was developed for the simultaneous determination of okadaic acid, dinophysistoxin-1 and dinophysistoxin-2 in shellfish using ultra performance liquid chromatography with tandem mass spectrometry. Shellfish poisons in spiked samples were extracted with methanol and 90% methanol, and were hydrolyzed with 2.5 mol/L sodium hydroxide solution. Purification was done on an HLB solid-phase extraction column. This method was validated in accordance with the notification of Ministry of Health, Labour and Welfare of Japan. As a result of the validation study in nine kinds of shellfish, the trueness, repeatability and within-laboratory reproducibility were 79-101%, less than 12 and 16%, respectively. The trueness and precision met the target values of notification. PMID:26936305

  19. 77 FR 36260 - Proposed Information Collection; Comment Request; Puget Sound Recreational Shellfish Harvesting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... Sound Recreational Shellfish Harvesting Project AGENCY: National Oceanic and Atmospheric Administration... information. The Puget Sound estuary provides one of the most valuable shellfish habitats in the Pacific Northwest. Shellfish are important economically, ecologically, and socially to the Puget Sound basin....

  20. National shellfish register of classified estuarine waters, 1990. Data supplement

    SciTech Connect

    Not Available

    1992-06-01

    The 1990 Register summarized data on 3,172 of the Nation's classified shellfish-growing areas. However, State and Federal shellfish officials often need area-specific data to manage their daily operations. The Data Supplement, therefore, provides detailed information about local classified shellfish-growing areas for both the 1985 and 1990 Registers. It also updates relevant information that has become available since the publication of the 1990 Register, specifically in the areas of classifications, pollution sources affecting shellfish-growing waters, harvests, and evolving issues.

  1. Complete genome sequence for the shellfish pathogen Vibrio coralliilyticus RE98 isolated from a shellfish hatchery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio coralliilyticus is a pathogen of corals and larval shellfish. Publications on strain RE98 list it as a Vibrio tubiashii; however, whole genome sequencing confirms RE98 as V. coralliilyticus containing a total of 6,037,824 bp consisting of two chromosomes (3,420,228 and 1,917,482 bp), and two...

  2. [Petroleum hydrocarbon pollution status in shellfish culture area of Sanggou Bay and effect on quality safety of shellfish].

    PubMed

    Qiao, Xiang-Ying; Chen, Bi-Juan; Zhou, Ming-Ying; Cui, Zheng-Guo

    2011-08-01

    Petroleum hydrocarbon concentrations in seawater, surface sediments and culture shellfish were investigated in shellfish culture area of Sanggou Bay from Jan. to Nov. in 2008. Investigation was conducted on the distribution and variation of petroleum hydrocarbon concentrations in seawater and sediments in the shellfish culture area of Sanggou Bay, as well as on the levels and the differences in petroleum hydrocarbon concentrations among the shellfish species. In addition, the petroleum hydrocarbon pollution status in the three media was evaluated and the effects of accumulated petroleum hydrocarbon in shellfish on the food safety risk were discussed. The results indicated: 1) Petroleum hydrocarbon concentrations in seawater in the shellfish culture area of Sanggou Bay were in the range of 3.61 - 98.21 microg/L; the mean values of petroleum hydrocarbon concentrations in sediments were in the range of 6.75-25.95 mg/kg; petroleum hydrocarbon concentrations in culture shellfish were in the range of 2.14- 42.87 mg/kg; and petroleum hydrocarbon concentrations in shellfish varied largely among different species, with the mean values in the sequence of clam Venerupis variegata > oyster > scallop; 2) Monthly petroleum hydrocarbon concentrations in seawater and surface sediments varied significantly in Sanggou Bay shellfish culture area, with the highest and the lowest values of petroleum hydrocarbon concentrations in seawater that occurred in July and in August, respectively, and with the highest and the lowest values of petroleum hydrocarbon concentrations in surface sediments that occurred in September and in March, respectively; 3) According to the corresponding evaluation criteria, the petroleum hydrocarbon pollution status in surface sediments in Sanggou Bay shellfish culture area was unpolluted but the status in surface seawater was polluted. The culture shellfish was also polluted by petroleum hydrocarbon with different degrees among three species, namely, the

  3. 50 CFR 14.21 - Shellfish and fishery products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 1 2013-10-01 2013-10-01 false Shellfish and fishery products. 14.21 Section 14.21 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Ports § 14.21 Shellfish and fishery products. (a)(1) General. Except for wildlife requiring a...

  4. 50 CFR 14.21 - Shellfish and fishery products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Shellfish and fishery products. 14.21 Section 14.21 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Ports § 14.21 Shellfish and fishery products. (a)(1) General. Except for wildlife requiring a...

  5. 50 CFR 14.21 - Shellfish and fishery products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 1 2011-10-01 2011-10-01 false Shellfish and fishery products. 14.21 Section 14.21 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Ports § 14.21 Shellfish and fishery products. (a)(1) General. Except for wildlife requiring a...

  6. New targets for expedient detection of viruses within shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously our laboratory developed an expedient method for extraction of viral RNA from food-borne virus contaminated bivalve shellfish, termed the GPTT protocol. This protocol utilizes either whole shellfish or dissected digestive diverticula. This four step protocol utilizes a high pH glycine or...

  7. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Subsistence taking of shellfish. 242.28 Section 242.28 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SUBSISTENCE MANAGEMENT REGULATIONS FOR PUBLIC LANDS IN ALASKA Subsistence Taking of Fish and Wildlife § 242.28 Subsistence taking of shellfish....

  8. Shellfish Toxins Targeting Voltage-Gated Sodium Channels

    PubMed Central

    Zhang, Fan; Xu, Xunxun; Li, Tingting; Liu, Zhonghua

    2013-01-01

    Voltage-gated sodium channels (VGSCs) play a central role in the generation and propagation of action potentials in excitable neurons and other cells and are targeted by commonly used local anesthetics, antiarrhythmics, and anticonvulsants. They are also common targets of neurotoxins including shellfish toxins. Shellfish toxins are a variety of toxic secondary metabolites produced by prokaryotic cyanobacteria and eukaryotic dinoflagellates in both marine and fresh water systems, which can accumulate in marine animals via the food chain. Consumption of shellfish toxin-contaminated seafood may result in potentially fatal human shellfish poisoning. This article provides an overview of the structure, bioactivity, and pharmacology of shellfish toxins that act on VGSCs, along with a brief discussion on their pharmaceutical potential for pain management. PMID:24287955

  9. Seafood-Associated Shellfish Allergy: A Comprehensive Review.

    PubMed

    Khora, Samanta S

    2016-08-01

    Shellfish are diverse, serve as main constituents of seafood, and are extensively consumed globally because of their nutritional values. Consequently, increase in reports of IgE-mediated seafood allergy is particularly food associated to shellfish. Seafood-associated shellfish consists of crustaceans (decapods, stomatopods, barnacles, and euphausiids) and molluskans (gastropods, bivalves, and cephalopods) and its products can start from mild local symptoms and lead to severe systemic anaphylactic reactions through ingestion, inhalation, or contact like most other food allergens. Globally, the most commonly causative shellfish are shrimps, crabs, lobsters, clams, oysters, and mussels. The prevalence of shellfish allergy is estimated to be 0.5-2.5% of the general population but higher in coastal Asian countries where shellfish constitute a large proportion of the diet. Diversity in allergens such as tropomyosin, arginine kinase, myosin light chain, and sarcoplasmic binding protein are from crustaceans whereas tropomyosin, paramyosin, troponin, actine, amylase, and hemoyanin are reported from molluskans shellfish. Tropomyosin is the major allergen and is responsible for cross-reactivity between shellfish and other invertebrates, within crustaceans, within molluskans, between crustaceans vs. molluskans as well as between shellfish and fish. Allergenicity diagnosis requires clinical history, in vivo skin prick testing, in vitro quantification of IgE, immunoCAP, and confirmation by oral challenge testing unless the reactions borne by it are life-threatening. This comprehensive review provides the update and new findings in the area of shellfish allergy including demographic, diversity of allergens, allergenicity, their cross-reactivity, and innovative molecular genetics approaches in diagnosing and managing this life-threatening as well as life-long disease. PMID:27404324

  10. Occurrence of potentially pathogenic arcobacters in shellfish.

    PubMed

    Mottola, Anna; Bonerba, Elisabetta; Figueras, Maria José; Pérez-Cataluña, Alba; Marchetti, Patrizia; Serraino, Andrea; Bozzo, Giancarlo; Terio, Valentina; Tantillo, Giuseppina; Di Pinto, Angela

    2016-08-01

    Considering that several recent cases of human gastroenteritis have been associated with species from the Arcobacter genus, and that few data are currently available about the occurrence of this genus in Italian shellfish, the aim of the present study was to evaluate the occurrence of Arcobacter spp. and the presence of virulence-associated genes. The approach consisted of cultural and biomolecular (multiplex-PCR and 16S-RFLP) methods identifying isolates, followed by PCR assays aimed at the cadF, ciaB, cjl349, irgA, hecA putative virulence genes. Arcobacter spp. was detected in 16/70 (22.8%) shellfish samples. Specifically, Arcobacter spp. was highlighted in 10/42 (23.8%) mussel and in 6/28 (21.4%) clam samples. Subsequently, biomolecular assays revealed Arcobacter butzleri in 12/16 (75%) and Arcobacter cryaerophilus 1B in 4/16 (25%) isolates. PCRs aimed at the five putative virulence genes demonstrated widespread distribution of these genes among Arcobacter isolates and some differences from the results published by other authors. Our research provides more information regarding the health risks associated with the consumption of raw bivalve molluscs and underlines the need to implement an adequate control plan by performing intensive and continuous monitoring in order to guarantee human health. PMID:27052698

  11. Advances in monitoring and toxicity assessment of brevetoxins in molluscan shellfish.

    PubMed

    Plakas, Steven M; Dickey, Robert W

    2010-08-15

    Herein, we describe advancements in monitoring of brevetoxins in molluscan shellfish, with respect to exposure management and control of neurotoxic shellfish poisoning (NSP). Current knowledge of the fate of brevetoxins in molluscan shellfish, and the toxic potency of brevetoxin metabolites, is presented. We review rapid assays for measuring composite brevetoxins, and methodology for measuring constituent brevetoxins, in contaminated shellfish. The applicability of in vitro methods for estimating brevetoxin burden and composite toxicity in shellfish is assessed. Specific and measurable biomarkers of brevetoxin exposure and toxicity in shellfish, and of human intoxication, are described. Their utility in regulatory monitoring of toxic shellfish and in clinical diagnosis of NSP is evaluated. PMID:19925816

  12. Environmental Transmission of Human Noroviruses in Shellfish Waters

    PubMed Central

    Lees, David N.

    2014-01-01

    Human noroviruses (NoV) are the most common cause of epidemic gastroenteritis following consumption of bivalve shellfish contaminated with fecal matter. NoV levels can be effectively reduced by some sewage treatment processes such as activated sludge and membrane bioreactors. However, tertiary sewage treatment and substantial sewage dilution are usually required to achieve low concentrations of virus in shellfish. Most outbreaks have been associated with shellfish harvested from waters affected by untreated sewage from, for example, storm overflows or overboard disposal of feces from boats. In coastal waters, NoV can remain in suspension or associate with organic and inorganic matter and be accumulated by shellfish. Shellfish take considerably longer to purge NoV than fecal indicator bacteria when transferred from sewage-polluted estuarine waters to uncontaminated waters. The abundance and distribution of NoV in shellfish waters are influenced by the levels of sewage treatment, proximity of shellfish beds to sewage sources, rainfall, river flows, salinity, and water temperature. Detailed site-specific information on these factors is required to design measures to control the viral risk. PMID:24705321

  13. Ionic bonding, the mechanism of viral uptake by shellfish mucus.

    PubMed Central

    Di Girolamo, R; Liston, J; Matches, J

    1977-01-01

    An investigation was conducted to determine the processes involved in the contamination of shellfish by viruses. Results of binding-release studies show that the process involves the attachment of viruses to mucus secreted, and then ingested, by shellfish during feeding. Analysis of the mucus-virus bond involved selective degradation of the mucus and use of chemical agents to block carboxyl and sulfate groups on the mucus. Results obtained indicate that the attachment of virus to mucus is primarily ionic and involves the binding of viral particles to sulfate radicals on the mucopolysaccharide moiety of shellfish mucus. PMID:13712

  14. Paralytic shellfish poisoning --- southeast Alaska, May--June 2011.

    PubMed

    2011-11-18

    On June 6, 2011, the Section of Epidemiology (SOE) of the Alaska Division of Public Health was notified of a case of paralytic shellfish poisoning (PSP) in southeast Alaska. In collaboration with local partners, SOE investigated and identified a total of eight confirmed and 13 probable PSP cases that occurred during May--June 2011. Warnings to avoid noncommercially harvested shellfish were broadcast on local radio and television and displayed at beaches and in post offices, government offices, and businesses throughout the region. Commercially harvested shellfish, which are tested for the presence of PSP-causing toxins, were safe. Because the risk for PSP is unpredictable, persons who consume noncommercially harvested Alaskan shellfish should know that they are at risk for PSP, and suspected cases should be reported promptly to SOE to initiate control measures in the affected area. PMID:22089968

  15. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  16. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  17. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  18. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  19. Climate Change May Bring More Tainted Shellfish to Northern Seas

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160300.html Climate Change May Bring More Tainted Shellfish to Northern Seas ... must be monitored "in the light of ongoing climate change, especially in coastal areas most heavily affected by ...

  20. Expanding shellfish aquaculture: A review of the ecological services provided by and impacts of native and cultured bivalves in shellfish dominated ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquaculture is making an increasing contribution to world-wide demand for bivalve shellfish at the same time that substantial efforts are being made to restore wild shellfish populations because they are declining. Impacts of shellfish culture to natural systems have been evaluated, but both native...

  1. Determination of brevetoxins in shellfish by the neuroblastoma assay.

    PubMed

    Truman, Penelope; Stirling, David J; Northcote, Peter; Lake, Robin J; Seamer, Catherine; Hannah, Donald J

    2002-01-01

    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. PMID:12374404

  2. Norovirus and other human enteric viruses in moroccan shellfish.

    PubMed

    Benabbes, Laila; Ollivier, Joanna; Schaeffer, Julien; Parnaudeau, Sylvain; Rhaissi, Houria; Nourlil, Jalal; Le Guyader, Françoise S

    2013-03-01

    The aim of this study was to evaluate the presence of human enteric viruses in shellfish collected along the Mediterranean Sea and Atlantic Coast of Morocco. A total of 77 samples were collected from areas potentially contaminated by human sewage. Noroviruses were detected in 30 % of samples, with an equal representation of GI and GII strains, but were much more frequently found in cockles or clams than in oysters. The method used, including extraction efficiency controls, allowed the quantification of virus concentration. As in previous reports, results showed levels of contamination between 100 and 1,000 copies/g of digestive tissues. Sapoviruses were detected in 13 % of samples mainly in oyster and clam samples. Hepatitis A virus was detected in two samples, with concentrations around 100 RNA copies/g of digestive tissues. Only two samples were contaminated with enterovirus and none with norovirus GIV or Aichi virus. This study highlights the interest of studying shellfish samples from different countries and different production areas. A better knowledge of shellfish contamination helps us to understand virus levels in shellfish and to improve shellfish safety, thus protecting consumers. PMID:23412717

  3. UK interpretation and implementation of the EEC Shellfish directive

    NASA Astrophysics Data System (ADS)

    Wathern, Peter; Young, Stephen N.; Brown, Ian W.; Roberts, Dawn A.

    1987-01-01

    The EEC Shellfish Directive is a policy designed to protect and, where necessary, improve the quality of designated shellfish waters. Its implementation within the UK, however, has had no effect upon water quality for two reasons. First, the policy has important defects, having ambiguities concerning public health provisions and lacking designation criteria. Second, UK government has sought to achieve formal compliance, while at the same time ensuring that its full financial impact on public expenditure has been contained. Consequently, only those fisheries which already comply with water quality standards have been designated. Within Wales, one fishery has been designated, while other, commercially more important, but grossly contaminated shellfisheries have not.

  4. Atypical profiles of paralytic shellfish poisoning toxins in shellfish from Luanda and Mussulo bays, Angola.

    PubMed

    Vale, Paulo; Rangel, Isabel; Silva, Bárbara; Coelho, Paulo; Vilar, Andrea

    2009-01-01

    Currently Angola does not possess a monitoring programme for shellfish contamination with marine biotoxins. Among other potentially toxic microalgae, the presence of Gymnodinium catenatum and Pyrodinium bahamense has been reported at the Angola coast, two species associated worldwide with production of paralytic shellfish poisoning toxins (PSTs). A preliminary assessment of contamination with PSTs was carried out by HPLC with pre-column derivatization in samples of Semele proficua from Luanda Bay and samples of Senilia senilis from Mussulo Bay, collected between June 2007 and February 2008. An unusual profile was found, not matching any of the 10 oxidation products expected from the known hydrophilic PSTs normally reported in marine dinoflagellates: the N-sulfocarbamoyl, the decarbamoyl or the carbamoyl analogues of saxitoxin (STX). Four major compounds were noted, and designated A through D. These were not autofluorescent, additionally A and D presented much stronger response after peroxide oxidation than after periodate oxidation. Fluorescence emission and ultraviolet absorption maxima were similar to oxidation products of STX analogues. Separation carried out in two different C18 columns clearly showed the retention times did not match the oxidation products of standards. In the period of August through October 2007, samples of S. proficua from Luanda Bay presented a strong cross-reaction with a commercial antibody towards STX, in the range of 2600-5800STXequiv./kg, while for the same period levels in the samples of S. senilis from Mussulo Bay ranged between <30 and 340STXequiv./kg. This reaction was directly proportional to the presence of the four unknown fluorescent peaks. The presence of these compounds was very persistent throughout the studied period, in particular in Luanda Bay. This contamination might not be characteristic of a dinoflagellate blooming, but could be related to a persistent cyanobacterial contamination, due to the strong sewage pollution

  5. Dinophysis Toxins: Causative Organisms, Distribution and Fate in Shellfish

    PubMed Central

    Reguera, Beatriz; Riobó, Pilar; Rodríguez, Francisco; Díaz, Patricio A.; Pizarro, Gemita; Paz, Beatriz; Franco, José M.; Blanco, Juan

    2014-01-01

    Several Dinophysis species produce diarrhoetic toxins (okadaic acid and dinophysistoxins) and pectenotoxins, and cause gastointestinal illness, Diarrhetic Shellfish Poisoning (DSP), even at low cell densities (<103 cells·L−1). They are the main threat, in terms of days of harvesting bans, to aquaculture in Northern Japan, Chile, and Europe. Toxicity and toxin profiles are very variable, more between strains than species. The distribution of DSP events mirrors that of shellfish production areas that have implemented toxin regulations, otherwise misinterpreted as bacterial or viral contamination. Field observations and laboratory experiments have shown that most of the toxins produced by Dinophysis are released into the medium, raising questions about the ecological role of extracelular toxins and their potential uptake by shellfish. Shellfish contamination results from a complex balance between food selection, adsorption, species-specific enzymatic transformations, and allometric processes. Highest risk areas are those combining Dinophysis strains with high cell content of okadaates, aquaculture with predominance of mytilids (good accumulators of toxins), and consumers who frequently include mussels in their diet. Regions including pectenotoxins in their regulated phycotoxins will suffer from much longer harvesting bans and from disloyal competition with production areas where these toxins have been deregulated. PMID:24447996

  6. AN RNA EXTRACTION PROTOCOL FOR SHELLFISH-BORNE VIRUSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The GPTT virus RNA extraction method, originally developed for extraction of human norovirus and hepatitis A virus RNAs from contaminated shellfish, was evaluated for extraction of RNA from Aichi virus strain A846/88 (AiV), coxsackievirus strains A9 (CAV9) and B5 (CBV5), murine norovirus (strain MNV...

  7. Sterol composition shellfish species commonly consumed in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shellfish commonly consumed in the U.S. were sampled and analyzed to update nutrient data in the United States Department of Agriculture (USDA) National Nutrient Database for Standard Reference (SR), using a nationwide sampling plan and validated analytical methodology. In 2007-8, raw shrimp and se...

  8. Overview of zoonotic infections from fish and shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As aquaculture production and consumption of aquacultural products increases, the possibility of zoonotic infection from either handling or ingestion of these products also increases. The principal pathogens acquired topically from fish or shellfish through spine/pincer puncture or open wounds are ...

  9. Accumulation of sediment-associated viruses in shellfish

    SciTech Connect

    Landry, E.F.; Vaughn, J.M.; Vicale, T.J.; Mann, R.

    1983-01-01

    The present study focused on the importance of contaminated sediments in shellfish accumulation of human viruses. Epifaunal (Crassostrea virginica) and infanual (Mercenaria mercenaria) shellfish, placed on or in cores, were exposed to either resuspended or undisturbed sediments containing bound poliovirus type 1 (LSc 2ab). Consistent bioaccumulation by oysters (four of five trials) was only noted when sediment-bound viruses occurred in the water column. Virus accumulation was observed in a single instance where sediments remained in an undisturbed state. While the incidence of bioaccumulation was higher with resuspended rather than undisturbed contaminated sediment, the actual concentration of accumulated viruses was not significantly different from the accumulation of viruses from oysters residing on uninoculated sediments. When clams were exposed to undisturbed, virus-contaminated sediments, two of five shellfish pools yielded viral isolates. Bioaccumulation of undisturbed sediments by these bivalves was considered marginal when related to the concentration of virus in contaminated sediments; they would only represent a significant threat when suspended in the water column. Arguments were advanced for water-column sampling in the region of the water-sediment interface to provide an accurate determination of the virological quality of shellfish harvesting waters.

  10. Accumulation of sediment-associated viruses in shellfish

    SciTech Connect

    Landry, E.F.; Vaughn, J.M.; Vicale, T.J.; Mann, R.

    1983-01-01

    The present study focused on the importance of contaminated sediments in shellfish accumulation of human viruses. Epifaunal (Crassostrea virginica) and infaunal (Mercemaria mercenaria) shellfish, placed on or in cores, were exposed to either resuspended or undisturbed sediments containing bound poliovirus type 1 (LSc 2ab). Consistent bioaccumulation by oysters (four of five trials) was only noted when sediment-bound viruses occurred in the water column. Virus accumulation was observed in a single instance where sediments remained in an undisturbed state. While the incidence of bioaccumulation was higher with resuspended rather than undisturbed contaminated sediment, the actual concentration of accumulated viruses was not significantly different. The accumulation of viruses from oysters residing on uninoculated sediments. When clams were exposed to undisturbed, virus-contaminated sediments, two of five shellfish pools yielded viral isolates. Bioaccumulation of undisturbed sediments by these bivalves was considered marginal when related to the concentration of virus in contaminated sediments; they would only represent a significant threat when suspended in the water column. Arguments were advanced for water-column sampling in the region of the water-sediment interface to provide an accurate determination of the virological quality of shellfish harvesting waters.

  11. Natural modulators of Vibrios in seawater and shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Naturally occurring marine bacteria, Vibrio parahaemolyticus and V. vulnificus, are major threats to the safety of molluscan shellfish in the US and elsewhere. Illnesses range from mild gastrointestinal upset to septicemia and death. In studies on the uptake and persistence of V. parahaemolyticus ...

  12. Potential virus detection and intervention methods for molluscan shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Norovirus is the number one cause of foodborne illness in the Unites States, causing an estimated 9 million cases/yr. Hepatitis A is uncommon in the US but can result in serious illness. Bivalve shellfish are efficient bioconcentrators of these viruses from contaminated growing waters. Consequentl...

  13. A Holistic Approach to the Conservation and Propagation of Freshwater, Brackish and Estuarine Bivalves for Ecosystem Services.

    NASA Astrophysics Data System (ADS)

    Kreeger, D.

    2005-05-01

    Shellfish restoration is increasingly valued in estuaries such as Chesapeake Bay where oyster populations are known to function as living biofilters, performing critical ecosystem services. Less studied are the services rendered by other suspension-feeding bivalves that reside in fringing marshes around these estuaries, in brackish and freshwater tidal portions, and in freshwater tributaries. The potential benefits contributed by other native bivalves will be discussed with two case studies from the Delaware basin. These are the ribbed mussel (Geukensia demissa ), which is abundant in brackish and marine tidal marshes, and the unionid mussel (Elliptio complanata ), which is abundant in many rivers of the system. Ribbed mussels are abundant enough to filter a large portion of the tidal prism flushing marshes, facilitating the role that these systems play as a sink for suspended solids and nutrients. Similarly, data from the lower Brandywine River suggests that a vestigial community of freshwater unionids remains sufficiently abundant to have a measurable beneficial effect on water quality by removing more than 25 metric tons of suspended particulates per year. Hence, the conservation and propagation of freshwater unionids can yield benefits that extend beyond current interest that is focused on protecting their biodiversity. Future efforts to protect or reclaim water quality and ecosystem integrity may benefit by a basin-wide, holistic approach that promotes integrated "biofiltration services" by native bivalves living from the headwaters to the coastal shelf.

  14. [Shellfish monitoring system for paralytic shellfish toxins using enzyme-linked immunosorbent assay].

    PubMed

    Shinozaki, Takashi; Watanabe, Ryuichi; Kawatsu, Kentaro; Sakurada, Kiyonari; Takahi, Shinya; Ueno, Ken-ichi; Matsushima, Ryoji; Suzuki, Toshiyuki

    2013-01-01

    We investigated the applicability of enzyme-linked immunosorbent assay (PSP-ELISA) using a monoclonal antibody against paralytic shellfish toxins (PST) for screening oysters collected at several coastal areas in Kumamoto prefecture, Japan. Oysters collected between 2007 and 2010 were analyzed by PSP-ELISA. As an alternative calibrant, a naturally contaminated oyster extract was used to quantify toxins in the oyster samples. The toxicity of the calibrant oyster extract determined by the official testing method, mouse bioassay (MBA), was 4 MU/g. Oyster samples collected over 3 years showed a similar toxin profile to the alternative standard, resulting in good agreement between the PSP-ELISA and the MBA. The PSP-ELISA method was better than the MBA in terms of sensitivity, indicating that it may be useful for earlier warning of contamination of oysters by PST in the distinct coastal areas. To use the PSP-ELISA as a screening method prior to MBA, we finally set a screening level at 2 MU/g PSP-ELISA for oyster monitoring in Kumamoto prefecture. We confirmed that there were on samples exceeding the quarantine level (4 MU/g) in MBA among samples quantified as below the screening level by the PSP-ELISA. It was concluded that the use of PSP-ELISA could reduce the numbers of animals needed for MBA testing. PMID:24389470

  15. Contribution of Shellfish Consumption to Lower Mercury Health Risk for Residents in Northern Jiaozhou Bay, China

    PubMed Central

    2015-01-01

    Fish and marine mammal consumption are an important pathway for human exposure to mercury. The low mercury content in shellfish poses a low mercury health risk to people who consume shellfish. The objectives of this study are to detect mercury concentrations in different species of shellfish and to calculate the mercury health risk from shellfish consumption among traditional residents near northern Jiaozhou Bay. A total of 356 shellfish samples, which comprised 7 species from 5 different places in northern Jiaozhou Bay, were collected from April to June in 2012. The average mercury content in the collected shellfish ranged from 0.024 mg·kg−1 to 0.452 mg·kg−1. A total of 44 shellfish samples (12.36%) had mercury levels exceeding the national pollution-free aquatic products limit (0.3 mg·kg−1). Generally, the viscus had the highest mercury content among all parts of the shellfish. A positive correlation between mercury content and total weight/edible part weight was found in most species of the collected shellfish. The results showed that shellfish consumption resulted in the lower risk of mercury exposure to residents based on the calculation of daily intake (DI) and target hazard quotient (THQ). PMID:26101470

  16. Liquid Chromatographic Determination of Amnesic Shellfish Poison in Mussels

    NASA Astrophysics Data System (ADS)

    Duxbury, Mark

    2000-10-01

    A simple, rapid, high-performance liquid chromatographic experiment suitable for undergraduate students is described for determining amnesic shellfish poison in mussels. The poison itself is an unusual naturally occurring amino acid, domoic acid, that has been found in seafood, particularly shellfish, worldwide. The symptoms of poisoning include amnesia (memory loss), loss of balance, mental confusion, nausea, vomiting, diarrhea, coma, and in extreme cases death. The domoic acid is extracted from homogenized mussel tissue by boiling in water for 5 minutes. The homogenate is cooled and centrifuged, and an aliquot of the supernatant is diluted and analyzed by isocratic HPLC using a C18 column and an acetonitrile-water mobile phase at pH 2.5 with UV detection at 242 nm.

  17. Pseudoalteromonas bacteria are capable of degrading paralytic shellfish toxins.

    PubMed

    Donovan, Carrie J; Garduño, Rafael A; Kalmokoff, Martin; Ku, John C; Quilliam, Michael A; Gill, Tom A

    2009-11-01

    Marine bacterial isolates cultured from the digestive tracts of blue mussels (Mytilus edulis) contaminated with paralytic shellfish toxins (PSTs) were screened for the ability to reduce the toxicity of a PST mixture. Seven isolates reduced the overall toxicity of the algal extract by > or = 90% within 3 days. These isolates shared at least 99% 16S rRNA gene sequence similarity with five Pseudoalteromonas spp. Phenotypic tests suggested that all are novel strains of Pseudoalteromonas haloplanktis. PMID:19717625

  18. Impact of Xynthia Tempest on Viral Contamination of Shellfish

    PubMed Central

    Grodzki, Marco; Ollivier, Joanna; Le Saux, Jean-Claude; Piquet, Jean-Côme; Noyer, Mathilde

    2012-01-01

    Viral contamination in oyster and mussel samples was evaluated after a massive storm with hurricane wind named “Xynthia tempest” destroyed a number of sewage treatment plants in an area harboring many shellfish farms. Although up to 90% of samples were found to be contaminated 2 days after the disaster, detected viral concentrations were low. A 1-month follow-up showed a rapid decrease in the number of positive samples, even for norovirus. PMID:22344664

  19. Pseudoalteromonas Bacteria Are Capable of Degrading Paralytic Shellfish Toxins▿ †

    PubMed Central

    Donovan, Carrie J.; Garduño, Rafael A.; Kalmokoff, Martin; Ku, John C.; Quilliam, Michael A.; Gill, Tom A.

    2009-01-01

    Marine bacterial isolates cultured from the digestive tracts of blue mussels (Mytilus edulis) contaminated with paralytic shellfish toxins (PSTs) were screened for the ability to reduce the toxicity of a PST mixture. Seven isolates reduced the overall toxicity of the algal extract by ≥90% within 3 days. These isolates shared at least 99% 16S rRNA gene sequence similarity with five Pseudoalteromonas spp. Phenotypic tests suggested that all are novel strains of Pseudoalteromonas haloplanktis. PMID:19717625

  20. Impact of xynthia tempest on viral contamination of shellfish.

    PubMed

    Grodzki, Marco; Ollivier, Joanna; Le Saux, Jean-Claude; Piquet, Jean-Côme; Noyer, Mathilde; Le Guyader, Françoise S

    2012-05-01

    Viral contamination in oyster and mussel samples was evaluated after a massive storm with hurricane wind named "Xynthia tempest" destroyed a number of sewage treatment plants in an area harboring many shellfish farms. Although up to 90% of samples were found to be contaminated 2 days after the disaster, detected viral concentrations were low. A 1-month follow-up showed a rapid decrease in the number of positive samples, even for norovirus. PMID:22344664

  1. N-Acetylcysteine boosts xenobiotic detoxification in shellfish.

    PubMed

    Peña-Llopis, Samuel; Serrano, Roque; Pitarch, Elena; Beltrán, Eduardo; Ibáñez, María; Hernández, Félix; Peña, Juan B

    2014-09-01

    Water pollution represents a threat of increasing importance to human health. Bivalve mollusks are filter-feeding organisms that can accumulate chemical and microbiological contaminants in their tissues from very low concentrations in the water or sediments. Consumption of contaminated shellfish is one of the main causes of seafood poisoning. Thus, marine bivalves are normally depurated in sterilized seawater for 48 h to allow the removal of bacteria. However, this depuration time might be insufficient to eliminate chemical contaminants from their tissues. We have developed a novel technology that accelerates up to fourfold the excretion rate of xenobiotics in bivalves by treatment with the antioxidant and glutathione (GSH) pro-drug N-acetylcysteine (NAC) during the depuration period. NAC improved dose-dependently the detoxification of the organophosphate (OP) pesticide fenitrothion in the mussel Mytilus galloprovincialis, diminishing its levels up to nearly a hundred fold compared to conventional depuration, by enhancing the glutathione S-transferase (GST) activity and inducing the GSH anabolism (GSH synthesis and reduction by glutathione reductase). Notably, this induction in GSH anabolism and GST activity was also observed in uncontaminated bivalves treated with NAC. As the GSH pathway is involved in the detoxification of many pollutants and biotoxins from harmful algal blooms, we validated this proof of principle in king scallops (Pecten maximus) that naturally accumulated the amnesic shellfish poisoning (ASP) toxin domoic acid. We illustrate here a method that enhances the elimination of organic contaminants in shellfish, opening new avenues of depuration of marine organisms. PMID:24880785

  2. Comparative analysis of modeled nitrogen removal by shellfish farms.

    PubMed

    Rose, Julie M; Bricker, Suzanne B; Ferreira, Joao G

    2015-02-15

    The use of shellfish aquaculture for nutrient removal and reduction of coastal eutrophication has been proposed. Published literature has indicated that nitrogen contained in harvested shellfish can be accurately estimated from shell length:nitrogen content ratios. The range of nitrogen that could be removed by a typical farm in a specific estuarine or coastal setting is also of interest to regulators and planners. Farm Aquaculture Resource Management (FARM) model outputs of nitrogen removal at the shellfish farm scale have been summarized here, from 14 locations in 9 countries across 4 continents. Modeled nitrogen removal ranged from 105 lbs acre(-1) year(-1) (12 g m(-2) year(-1)) to 1356 lbs acre(-1) year(-1) (152 g m(-2) year(-1)). Mean nitrogen removal was 520 lbs acre(-1) year(-1) (58 g m(-2) year(-1)). These model results are site-specific in nature, but compare favorably to reported nitrogen removal effectiveness of agricultural best management practices and stormwater control measures. PMID:25534625

  3. Studies in the Use of Magnetic Microspheres for Immunoaffinity Extraction of Paralytic Shellfish Poisoning Toxins from Shellfish

    PubMed Central

    Devlin, Raymond; Campbell, Katrina; Kawatsu, Kentaro; Elliott, Christopher

    2011-01-01

    Paralytic shellfish poisoning (PSP) is a potentially fatal human health condition caused by the consumption of shellfish containing high levels of PSP toxins. Toxin extraction from shellfish and from algal cultures for use as standards and analysis by alternative analytical monitoring methods to the mouse bioassay is extensive and laborious. This study investigated whether a selected MAb antibody could be coupled to a novel form of magnetic microsphere (hollow glass magnetic microspheres, brand name Ferrospheres-N) and whether these coated microspheres could be utilized in the extraction of low concentrations of the PSP toxin, STX, from potential extraction buffers and spiked mussel extracts. The feasibility of utilizing a mass of 25 mg of Ferrospheres-N, as a simple extraction procedure for STX from spiked sodium acetate buffer, spiked PBS buffer and spiked mussel extracts was determined. The effects of a range of toxin concentrations (20-300 ng/mL), incubation times and temperature on the capability of the immuno-capture of the STX from the spiked mussel extracts were investigated. Finally, the coated microspheres were tested to determine their efficiency at extracting PSP toxins from naturally contaminated mussel samples. Toxin recovery after each experiment was determined by HPLC analysis. This study on using a highly novel immunoaffinity based extraction procedure, using STX as a model, has indicated that it could be a convenient alternative to conventional extraction procedures used in toxin purification prior to sample analysis. PMID:22069687

  4. Does traditional shellfishing affect foraging by waders? The case of the Tagus estuary (Portugal)

    NASA Astrophysics Data System (ADS)

    Dias, Maria P.; Peste, Filipa; Granadeiro, José P.; Palmeirim, Jorge M.

    2008-03-01

    Estuarine intertidal flats are often exploited by humans and waders since they provide food, particularly shellfish. This raises important conservation issues. Waders can be affected by shellfishing activities in multiple ways, such as a reduction of the available shellfish, disturbance by the presence of shellfishers on their feeding areas, and changes in micro-habitat, due to sediment reworking. In this study we quantified the impact of traditional shellfishing on waders in the Tagus estuary. Particular attention was given to hand-raking of clams Scrobicularia plana, which constitutes most of the consumed food by waders. Shellfishers did not cause a relevant depletion of clams for waders; they removed less than 0.3% of its total production and focused on size classes that were usually not taken by birds. Hand-raking caused temporary changes in the vertical distribution and availability of invertebrate prey in the sediment. However, this did not affect the bird's feeding rates, presumably because prey availability remained above the threshold at which intake rates are expected to decline. The presence of shellfishers in the birds foraging areas potentially affects waders by keeping them away from foraging areas, but even the most affected species lost less than 10% of their foraging grounds due to this factor. Overall, we conclude that the current low harvesting levels of shellfishing are compatible with the preservation of the estuary as a key site for waders. Nevertheless, simulations showed that traditional shellfishing could have much greater potential to affect waders through disturbance than through prey removal. The results for the Tagus show that even small harvest rates, representing a negligible loss of food for waders and potentially considered sustainable by shellfish managers, could have a great impact on waders due to increased disturbance. This effect of disturbance likely occurs in most estuaries and should be taken into consideration when planning

  5. Isolation of naturally occurring enteroviruses from a variety of shellfish species residing in Long Island and New Jersey marine embayments

    SciTech Connect

    Vaughn, J.M.; Landry, E.F.; Vicale, T.J.; Dahl, M.C.

    1980-02-01

    Shellfish and shellfish-raising waters from a variety of Long Island and New Jersey marine embayments were examined for the presence of human enteroviruses. Little difference in virological quality was noted between areas designated as being open or closed to shellfishing. Viral isolations could not be correlated with coliform counts from identical samples, indicating the need to re-evaluate the use of bacterial standards as indices of the overall sanitary quality of water and shellfish.

  6. Fish- and shellfish--borne trematode infections in Canada.

    PubMed

    Dixon, B R; Flohr, R B

    1997-01-01

    Food-borne trematode infections are endemic in various parts of the world, particularly Southeast Asia. Despite the high prevalence, morbidity and total costs of these infections, they remain poorly recognized by public health authorities and consumers. Factors such as poor sanitation and traditional methods of food preparation hasten the spread of food-borne trematode infections in endemic regions and must be carefully examined in order to develop effective control strategies. There is also a growing risk to consumers in non-endemic countries as a result of international trade. A considerable quantity of freshwater fish and shellfish is imported into Canada from endemic countries in Southeast Asia. Some of these products are imported fresh or processed in such a way that the infective metacercariae may not be destroyed. Further, current inspection procedures in Canada may not detect the presence of all parasites in imported fish products. Therefore, there may be a risk of infection if the fish or shellfish is consumed raw or lightly cooked. Many of the cases of infection in Canada involve recent immigrants from endemic regions who have become infected either before arriving or through the consumption of traditional or ethnic dishes prepared from imported products. International travel and the increasing availability and interest in ethnic foods also contribute to the risk of infection in all Canadians. In addition to these imported trematodes, a number of species are found in freshwater fishes and shellfish in North America and have also caused illness in humans. Although the prevalence of infection remains relatively low in Canada, the need for an increased general awareness of food-borne trematode infections and their causes is indicated. PMID:9656351

  7. Parallel Analyses of Alexandrium catenella Cell Concentrations and Shellfish Toxicity in the Puget Sound▿

    PubMed Central

    Dyhrman, Sonya T.; Haley, Sheean T.; Borchert, Jerry A.; Lona, Bob; Kollars, Nicole; Erdner, Deana L.

    2010-01-01

    Alexandrium catenella is widespread in western North America and produces a suite of potent neurotoxins that cause paralytic shellfish poisoning (PSP) in humans and have deleterious impacts on public health and economic resources. There are seasonal PSP-related closures of recreational and commercial shellfisheries in the Puget Sound, but the factors that influence cell distribution, abundance, and relationship to paralytic shellfish toxins (PSTs) in this system are poorly described. Here, a quantitative PCR assay was used to detect A. catenella cells in parallel with state shellfish toxicity testing during the 2006 bloom season at 41 sites from April through October. Over 500,000 A. catenella cells liter−1 were detected at several stations, with two main pulses of cells driving cell distribution, one in June and the other in August. PSTs over the closure limit of 80 μg of PST 100 per g of shellfish tissue were detected at 26 of the 41 sites. Comparison of cell numbers and PST data shows that shellfish toxicity is preceded by an increase in A. catenella cells in 71% of cases. However, cells were also observed in the absence of PSTs in shellfish, highlighting the complex relationship between A. catenella and the resulting shellfish toxicity. These data provide important information on the dynamics of A. catenella cells in the Puget Sound and are a first step toward assessing the utility of plankton monitoring to augment shellfish toxicity testing in this system. PMID:20495054

  8. Arsenic Concentrations and Speciation in Shellfishes from Korea

    NASA Astrophysics Data System (ADS)

    Yoon, C.; Yoon, H.

    2005-12-01

    Speciation of arsenic has received significant attention over the past 20 years in both mechanistic and exposure assessment research. Because the toxicity of arsenic is related to its oxidation state and its chemical forms, the determination of the total arsenic contents in a sample is not adequate to allow its impact on living organisms to be estimated. The inorganic arsenic species, arsenite (As3+) and arsenate (As5+), have been classified as carcinogenic and the methylated forms, monomethyl arsonic acid (MMA) and dimethyl arsinic acid (DMA) have recently been identified as cancer promoters. The highly methylated compounds like as arsenobetaine (AsB) and arsenocholine (AsC) are considered to be nontoxic. Although organisms in marine environment contain high amounts of total arsenic (ppm level), it is not usually present as inorganic arsenic or simple methylated forms well known as one of the toxic species. Arsenobetaine is the dominant species in marine animals and arsenosugars are most abundant in marine algae. This study aims to clarify those arsenic species present in the whole body of eleven different shellfishes from Korea. And those arsenic species were separated and measured by characterization using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) coupled system. The separation of arsenic species was achieved on anion exchange column and cation exchange column using phosphate and pyridine eluent, respectively. The ultrasonic extraction was employed for extraction of arsenic from whole body of shellfishes. The method was validated by analyzing three certified reference materials (DORM-2, TORT-2, 1566b). Total arsenic concentrations ranged from 0.1 mg/kg dry mass to 21.7 mg/kg dry mass. Most marine shellfishes contained higher arsenobetaine and arsenocholine with the exception of two shellfishes living in river. The lower amounts of inorganic arsenic species were also found in the some sample extracts

  9. [Carrying capacity of shellfish culture in Dadeng Island sea area of Xiamen].

    PubMed

    Lu, Zhenbin; Du, Qi; Fang, Minjie; Qian, Xiaoming; Cai, Qinghai; Xu, Cuiya

    2005-05-01

    To fully and rationally exploit local living marine resources while have a sustainable, efficient and healthy development of shellfish culture in the Dadeng Island sea area of Xiamen, this paper determined and analyzed the related model parameters of this area, including chlorophyll a, primary productivity, phytoplankton organic carbon tent, wild filter feeder yields in subtidal and intertidal zones and suspension culture area, cultured shellfish filtration rate and organic carbon content, shellfish's total weight to fresh meat ratio, and adopted the Nutrient namic Model and Coastal Waters' Energy Flow Analysis Model to estimate the ecological capacity of shellfish this area, from which, the wild filter feeder yields were deducted for estimating shellfish carrying capacity. model established by Fang Jianguang was also used to estimate the shellfish carrying capacity. Statistics analysis was used to estimate the suitable culture area of shellfish and other species, aiming at limiting local shellfish ture and optimizing the culture of various species mollusks. According to the estimation of the three models, shellfish carrying capacity in this area should be 35,248-39,990 tons, with an average of 37,488 tons, 140,008 x 10(4) - 158,850 x 10(4) individuals, averaging 148,903 x 10(4). The theoretically suitable culture area 2 145 hm2, 1,900 hm2 for Ostreidae, 81 hm2 for razor clam (Sinonovacula constricta), 20 hm2 for blood (Tegillarca granosa), and 144 hm2 for musculus (Musculus senhousei). In 2000, the actual culture area of shellfish and other species in the waters around Dadeng surpassed the estimated suitable culture area. It is proposed that some measures should be taken to reduce the overexploited area. PMID:16110680

  10. Probabilistic dietary exposure to phycotoxins in a recreational shellfish harvester subpopulation (France).

    PubMed

    Picot, Cyndie; Limon, Gwendolina; Durand, Gaël; Parent-Massin, Dominique; Roudot, Alain-Claude

    2013-07-01

    Phycotoxins, secondary phytoplankton metabolites, are considered as an important food safety issue because their accumulation by shellfish may render them unfit for human consumption. However, the likely intakes of phycotoxins via shellfish consumption are almost unknown because both contamination and consumption data are very scarce. Thus, two 1-year surveys were conducted (through the same population: recreational shellfish harvesters and from the same geographical area) to assess: shellfish consumption and contamination by major toxins (domoic acid (DA) group, okadaic acid (OA) group and spirolides (SPXs)). Recreational shellfish harvesters had been targeted as an at-risk subpopulation because they consume more shellfish than general population and because they eat not only commercial shellfish species controlled by official authorities but also their own harvests of shellfish species may be in non-controlled areas and more over shellfish species non-considered in the official control species. Then, these two kinds of data were combined with deterministic and probabilistic approaches for both acute and chronic exposures, on considering the impact of shellfish species and cooking on phycotoxin levels. For acute risk, monitoring programs seem to be adequate for DAs, whereas OAs could be a matter of concern for high consumers (their acute intakes were up to ninefold the acute reference dose (ARfD)). About chronic risk, OAs are a matter of concern. The daily OAs intakes were close to the ARfD, which is, by definition, greater than the tolerable daily intake. Moreover, SPX contamination is low but regular, no (sub)chronic SPX toxicity data exist; but in case of (sub)chronic toxicity, SPX exposure should be considered. PMID:22760440

  11. Non-Traditional Vectors for Paralytic Shellfish Poisoning

    PubMed Central

    Deeds, Jonathan R.; Landsberg, Jan H.; Etheridge, Stacey M.; Pitcher, Grant C.; Longan, Sara Watt

    2008-01-01

    Paralytic shellfish poisoning (PSP), due to saxitoxin and related compounds, typically results from the consumption of filter-feeding molluscan shellfish that concentrate toxins from marine dinoflagellates. In addition to these microalgal sources, saxitoxin and related compounds, referred to in this review as STXs, are also produced in freshwater cyanobacteria and have been associated with calcareous red macroalgae. STXs are transferred and bioaccumulate throughout aquatic food webs, and can be vectored to terrestrial biota, including humans. Fisheries closures and human intoxications due to STXs have been documented in several non-traditional (i.e. non-filter-feeding) vectors. These include, but are not limited to, marine gastropods, both carnivorous and grazing, crustacea, and fish that acquire STXs through toxin transfer. Often due to spatial, temporal, or a species disconnection from the primary source of STXs (bloom forming dinoflagellates), monitoring and management of such non-traditional PSP vectors has been challenging. A brief literature review is provided for filter feeding (traditional) and non-filter feeding (non-traditional) vectors of STXs with specific reference to human effects. We include several case studies pertaining to management actions to prevent PSP, as well as food poisoning incidents from STX(s) accumulation in non-traditional PSP vectors. PMID:18728730

  12. Paralytic shellfish poisoning (PSP) in Margarita Island, Venezuela.

    PubMed

    La Barbera-Sánchez, Amelia; Franco Soler, Jose; Rojas de Astudillo, Luisa; Chang-Yen, Ivan

    2004-09-01

    A severe outbreak of Paralytic Shellfish Poisoning (PSP) occurred in Manzanillo and Guayacán, northwestern coast of Margarita Island, Venezuela, between August and October 1991. A bloom of dinoflagellates including Prorocentrum gracile, Gymnodinium catenatum and Alexandrium tamarense seemed to be responsible for this outbreak. Levels of PSP toxins in mussels (Perna perna) exceeded the international safety limit of saxitoxin, 80 microg STX/100 microg meat. PSP toxin values varied between 2548 and 115 microg STX/100 g meat in Manzanillo, and between 1422 and 86 microg STX/100 g meat in Guayacán. At both locations, the highest levels were detected in August, when 24 patients exhibited typical symptoms of PSP toxicity after consuming cooked mussels (16 required hospitalization). A high pressure liquid chromatographic (HPLC) procedure was recently used on the 1991 samples. The major toxin detected in samples of both locations was decarbamoyl saxitoxin (dcSTX), but low concentrations of saxitoxin were also found in Manzanillo samples. Gonyautoxins GTX1, GTX2 and GTX3 were detected only at Guayacán, while in both locations, decarbamoylgonyatouxin (dcGTX2,3) toxins were detected. These findings represent the first time that causative toxins of PSP in Venezuela have been chemically identified, and confirm the presence of dcSTX and dcGTX in mussels from the Caribbean Sea. The presence of dcSTX and dcGTX in shellfish is indicative that Gymnodinium catenatum was a causative organism for outbreak of PSP. PMID:17465121

  13. Enteric viruses in a mangrove lagoon, survival and shellfish incidence

    SciTech Connect

    Lopez de Cardona, I.; Bermudez, M.; Billmire, E.; Hazen, T.C.

    1988-12-31

    Mangrove oysters (Crassostrea rhizophorae) were screened for enteric viruses. For 18 months oysters were collected from Cano Boqueron, a tropical mangrove lagoon on the southwest coast of Puerto Rico. This popular tourist resort has two primary sewage treatment plants which service 158 single family cabanas. In spite of the heavy seasonal input of sewage to Cano Boqueron and high densities of fecal coliform bacteria, enteric viruses were not detected in shellfish meat. Because no viruses were detected in the oysters, a virus survival study was performed. Poliovirus type 1 was placed in diffusion chambers in situ at two sites in Cano Boqueron. More than 95% of the poliovirus inactivation occurred within 24 h. Virus inactivation was significantly different by site, indicating different inactivation rates within the lagoon. Chamber studies done simultaneously with Escherichia coli did not reveal differences between sites. It is suggested that the sewage effluent had an antiviral effect in the absence of an antibacterial effect. This study demonstrates the importance for establishing microbial contamination standards for shellfish growing waters in the tropics based upon in situ studies with tropical species, e.g. mangrove oyster.

  14. Non-traditional vectors for paralytic shellfish poisoning.

    PubMed

    Deeds, Jonathan R; Landsberg, Jan H; Etheridge, Stacey M; Pitcher, Grant C; Longan, Sara Watt

    2008-01-01

    Paralytic shellfish poisoning (PSP), due to saxitoxin and related compounds, typically results from the consumption of filter-feeding molluscan shellfish that concentrate toxins from marine dinoflagellates. In addition to these microalgal sources, saxitoxin and related compounds, referred to in this review as STXs, are also produced in freshwater cyanobacteria and have been associated with calcareous red macroalgae. STXs are transferred and bioaccumulate throughout aquatic food webs, and can be vectored to terrestrial biota, including humans. Fisheries closures and human intoxications due to STXs have been documented in several non-traditional (i.e. non-filter-feeding) vectors. These include, but are not limited to, marine gastropods, both carnivorous and grazing, crustacea, and fish that acquire STXs through toxin transfer. Often due to spatial, temporal, or a species disconnection from the primary source of STXs (bloom forming dinoflagellates), monitoring and management of such non-traditional PSP vectors has been challenging. A brief literature review is provided for filter feeding (traditional) and non-filter feeding (non-traditional) vectors of STXs with specific reference to human effects. We include several case studies pertaining to management actions to prevent PSP, as well as food poisoning incidents from STX(s) accumulation in non-traditional PSP vectors. PMID:18728730

  15. Analysis of paralytic shellfish toxins and their metabolites in shellfish from the North Yellow Sea of China.

    PubMed

    Li, A; Ma, J; Cao, J; Wang, Q; Yu, R; Thomas, K; Quilliam, M A

    2012-01-01

    Samples of toxic scallop (Patinopecten yessoensis) and clam (Saxidomus purpuratus) collected on the northern coast of China from 2008 to 2009 were analysed. High-performance liquid chromatography with post-column oxidation and fluorescence detection was used to determine the profile of the main paralytic shellfish poisoning (PSP) toxins in these samples and their total toxicity. Hydrophilic interaction liquid ion chromatography with mass spectrometric detection confirmed the toxin profile and detected several metabolites in the shellfish. Results show that C1/2 toxins were the most dominant toxins in the scallop and clam samples. However, GTX1/4 and GTX2/3 were also present. M1 was the predominant metabolite in all the samples, but M3 and M5 were also identified, along with three previously unreported presumed metabolites, M6, M8 and M10. The results indicate that the biotransformation of toxins was species specific. It was concluded that the reductive enzyme in clams is more active than in scallops and that an enzyme in scallops is more apt to catalyse hydrolysis of both the sulfonate moiety at the N-sulfocabamoyl of C toxins and the 11-hydroxysulfate of C and GTX toxins to produce metabolites. This is the first report of new metabolites of PSP toxins in scallops and clams collected in China. PMID:22827221

  16. The presence of genogroup II norovirus in retail shellfish from seven coastal cities in China.

    PubMed

    Ma, Li-ping; Zhao, Feng; Yao, Lin; Li, Xin-guang; Zhou, De-qing; Zhang, Rui-ling

    2013-06-01

    Noroviruses (NoVs) are commonly occurring pathogens that cause gastroenteritis. Outbreaks of viral diseases have often been ascribed to the consumption of contaminated shellfish. Our objective was to evaluate the presence and contamination levels of NoV in shellfish sold at seafood markets in China. We tested 840 shellfish samples (Crassostrea gigas, Mytilus edulis, Azumapecten farreri, SinoNoVacula constricta, Scapharca subcrenata, Ruditapes philippinarum) that were collected from seven cities around the Yellow and Bohai Seas in China between December 2009 and November 2011. We used real-time RT-PCR to detect NoV in purified concentrates from the stomach and digestive diverticula of these shellfish. NoV was detected in 19.35 % (N = 155), 16.67 % (N = 114), 5.70 % (N = 158), 8.82 % (N = 136), 13.74 % (N = 131), and 16.44 % (N = 146) of oyster, mussel, scallop, razor clam, ark shell, and clam samples, respectively. The average detection rate was 13.33 % (112/840). Nucleotide sequencing of the NoV RT-PCR products demonstrated that all strains belonged to NoV genotype GII.12, except two that belonged to GI.3. More than 10² copies of the NoV genome were detected in 69 of 112 positive shellfish samples. Our results suggest that ~13 % of shellfish harbor NoV, and GII.12 NoV is the primary strain in shellfish purchased at markets in seven coastal cities in China. PMID:23412724

  17. Microbiological quality of frozen breaded fish and shellfish products.

    PubMed Central

    Baer, E F; Duran, A P; Leininger, H V; Read, R B; Schwab, A H; Swartzentruber, A

    1976-01-01

    A survey was made of the microbiological quality of seven frozen, breaded, precooked fish and shellfish products and of frozen, breaded, uncooked shrimp at the retail level. Geometric mean aerobic plate counts per gram (and number of units examined) were as follows: fish sticks, 8,300 (1,539); fish cakes, 5,600 (1,378); crab cakes, 4,900 (1,226); scallops, 1,700 (1,392); clams, 450 (1,384); haddock, 15,000 (1,306); fish in fish and chips dinner, 7,200 (1,485); and uncooked shrimp, 220,000 (1,462). Geometric mean coliform, Escherichia coli, and Staphylococcus aureus counts for all eight products ranged from 1 to 10/g. PMID:779643

  18. Microbiological quality of frozen breaded fish and shellfish products.

    PubMed

    Baer, E F; Duran, A P; Leininger, H V; Read, R B; Schwab, A H; Swartzentruber, A

    1976-03-01

    A survey was made of the microbiological quality of seven frozen, breaded, precooked fish and shellfish products and of frozen, breaded, uncooked shrimp at the retail level. Geometric mean aerobic plate counts per gram (and number of units examined) were as follows: fish sticks, 8,300 (1,539); fish cakes, 5,600 (1,378); crab cakes, 4,900 (1,226); scallops, 1,700 (1,392); clams, 450 (1,384); haddock, 15,000 (1,306); fish in fish and chips dinner, 7,200 (1,485); and uncooked shrimp, 220,000 (1,462). Geometric mean coliform, Escherichia coli, and Staphylococcus aureus counts for all eight products ranged from 1 to 10/g. PMID:779643

  19. Cell bioassay for paralytic shellfish poisoning (PSP): comparison with postcolumn derivatization liquid chromatographic analysis and application to the monitoring of PSP in shellfish.

    PubMed

    Hayashi, Rumiko; Saito, Hiroshi; Okumura, Masanao; Kondo, Fumio

    2006-01-25

    We performed a neuroblastoma cell (Neuro2a) culture assay modified slightly from a method reported previously to provide a simple and sensitive evaluation of paralytic shellfish poisoning (PSP) toxicity in shellfish. The cell bioassay was just as sensitive for C-toxins as for gonyautoxins. The sensitivity of our cell bioassay was 4 times that of the current standard mouse bioassay. Using the cell bioassay, we evaluated PSP toxicity in 361 shellfish samples collected from Mikawa Bay and Ise Bay, Aichi Prefecture, Japan, from April 1999-March 2002. The results were compared with those obtained in a postcolumn derivatization liquid chromatographic analysis. PSP toxins were detected in 236/361 samples by both assays, and there was a fairly good correlation (r = 0.9001, n = 236, p < 0.001) between the results from the two assays. We applied this cell bioassay when short-necked clams in the bay turned poisonous in 2001. The chronological changes in PSP toxicity in the short-necked clams were analyzed and compared with those of the cell density of poisonous plankton (Alexandrium tamarense) occurring in the bay. The PSP toxicity in shellfish peaked 2 weeks after the cell density reached a maximum. We recommend using the cell bioassay for routine monitoring of PSP toxicity in shellfish living in natural marine environments. PMID:16417278

  20. Discover the Atlantic Ocean: An Exciting Coloring Book of Fish and Shellfish.

    ERIC Educational Resources Information Center

    Flick, George J.

    This coloring book contains pictures of more than 79 fish and shellfish found on the Atlantic Coast. Captions give information on habitats, behavior, or commercial uses of the species pictured. Indexes of both common and scientific names are given. (BB)

  1. Shellfish from Todos os Santos Bay, Bahia, Brazil: treat or threat?

    PubMed

    de Souza, Manuel M; Windmöller, Cláudia C; Hatje, Vanessa

    2011-10-01

    This study determined the concentrations of major and trace elements in shellfish (oysters, clams and mussels) and conducted an assessment of the health risks due to the consumption of contaminated seafood. Samples were collected at 34 sites along Todos os Santos Bay, Brazil. The elements were determined by ICP OES and Hg by Direct Mercury Analysis. Relatively high concentrations of trace elements (As, Zn, Se and Cu) were found in seafood tissues. Potential daily intake of As, Co, Se, Zn and Cu associated to shellfish consumption suggested relevant non-carcinogenic risk for all studied locations. Copper was the element that posed the greatest non-carcinogenic risk, while Pb posed the highest carcinogenic risk. Health risks for humans were greatest from the consumption of mussels. Contaminated shellfish offer the greatest risk for children, subsistence fishers and subsistence shellfish consumers. PMID:21803378

  2. Transmission of viruses through shellfish : when specific ligands come into play

    PubMed Central

    Le Guyader, Françoise S.; Atmar, Robert L.; Le Pendu, Jacques

    2013-01-01

    Shellfish are known as vectors for human pathogens and despite regulation based on enteric bacteria they are still implicated in viral outbreaks. Among shellfish, oysters are the most common vector of contamination and the pathogens most frequently involved in these outbreaks are noroviruses, responsible for acute gastroenteritis in humans. Analysis of shellfish related outbreak data worldwide show an unexpected high proportion of NoV GI strains. Recent studies performed in vitro, in vivo and in the environment indicate that oysters are not just passive filter, but can selectively accumulate norovirus strains based on virus carbohydrate ligands shared with humans. These observations contribute to explain the GI/GII bias observed in shellfish-related outbreaks compared to other outbreaks. PMID:22440973

  3. High pressure processing of bivalve shellfish and HPP's potential use as a virus intervention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bivalve shellfish readily bioconcentrate pathogenic microbes and substance, such as algal and dinoflagulate toxins, fecal viruses and bacteria, and naturally present vibrio bacteria. High pressure processing (HPP) is currently used as an intervention for Vibrio vulnificus bacteria within molluscan ...

  4. PECONIC ESTUARY: AN ASSESSMENT OF SHELLFISH RESOURCES IN THE TRIBUTARIES AND EMBAYMENTS OF THE PECONIC ESTUARY

    EPA Science Inventory

    Executive Summary Historically, the Peconic Estuary's shellfish resources have supported significant fisheries for a number of species including hard clams, oysters and bay scallops. However, distribution and abundance data for the tributaries and embayments within the Peconic Es...

  5. Processing Strategies to Inactivate Enteric Viruses in Shellfish: Limitations of Surrogate Viruses and Molecular Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Noroviruses, hepatitis A and E viruses, sapovirus, astrovirus, rotavirus, Aichi virus, enteric adenoviruses, poliovirus, and other enteroviruses enter shellfish through contaminated seawater or by contamination during handling and processing, resulting in outbreaks ranging from isolated to epidemic....

  6. Screening Tests for the Rapid Detection of Diarrhetic Shellfish Toxins in Washington State

    PubMed Central

    Eberhart, Bich-Thuy L.; Moore, Leslie K.; Harrington, Neil; Adams, Nicolaus G.; Borchert, Jerry; Trainer, Vera L.

    2013-01-01

    The illness of three people due to diarrhetic shellfish poisoning (DSP) following their ingestion of recreationally harvested mussels from Sequim Bay State Park in the summer of 2011, resulted in intensified monitoring for diarrhetic shellfish toxins (DSTs) in Washington State. Rapid testing at remote sites was proposed as a means to provide early warning of DST events in order to protect human health and allow growers to test “pre-harvest” shellfish samples, thereby preventing harvest of toxic product that would later be destroyed or recalled. Tissue homogenates from several shellfish species collected from two sites in Sequim Bay, WA in the summer 2012, as well as other sites throughout Puget Sound, were analyzed using three rapid screening methods: a lateral flow antibody-based test strip (Jellett Rapid Test), an enzyme-linked immunosorbent assay (ELISA) and a protein phosphatase 2A inhibition assay (PP2A). The results were compared to the standard regulatory method of liquid chromatography coupled with tandem mass spectroscopy (LC-MS/MS). The Jellett Rapid Test for DSP gave an unacceptable number of false negatives due to incomplete extraction of DSTs using the manufacturer’s recommended method while the ELISA antibody had low cross-reactivity with dinophysistoxin-1, the major toxin isomer in shellfish from the region. The PP2A test showed the greatest promise as a screening tool for Washington State shellfish harvesters. PMID:24084788

  7. Domoic acid--a new toxin in the Croatian Adriatic shellfish toxin profile.

    PubMed

    Ujević, Ivana; Ninčević-Gladan, Zivana; Roje, Romana; Skejić, Sanda; Arapov, Jasna; Marasović, Ivona

    2010-01-01

    This is the first study that presents concentrations of domoic acid detected in the whole shellfish tissue from breeding and harvesting areas along the Croatian coast of the Adriatic Sea during the period 2006 to 2008. Shellfish sample analyses after SAX cleaning procedures, using a UV-DAD-HPLC system, showed the presence of domoic acid in four species. The most prevalent of those species were the blue mussel (Mytilus galloprovincialis), followed by European flat oyster (Ostrea edulis), Mediterranean scallop (Pecten jacobaeus) and proteus scallop (Flexopecten proteus). Domoic acid, a potentially lethal phycotoxin that causes amnesic shellfish poisoning (ASP), was detected for the first time in January 2006 with the highest value of 6.5486 μg g⁻¹ in whole shellfish tissue. Pseudo-nitzschia spp. bloom events preceded these high domoic acid concentrations. According to this study, retention of domoic acid in the blue mussel M. galloprovincialis is more than 42 days. This investigation indicates the first presence of domoic acid in Croatian shellfish, but in concentrations under the regulatory limit (20 μg g⁻¹), therefore shellfish consumption was not found to endanger human health. PMID:20938398

  8. A management strategy to reduce bacterial pollution in shellfish areas: A case study

    NASA Astrophysics Data System (ADS)

    Crane, Stuart R.; Moore, James A.

    1986-01-01

    The problem of bacterial pollution in shellfishing areas is not uncommon in the coastal regions of the United States. Bacterial contamination from man's activities can effectively reduce our natural shellfish resource areas by forcing their closure because of high potential risk of diseases being spread by shellfish harvested in these areas. Tillamook Bay, a relatively small, enclosed drainage basin of nonurban character, presents an excellent study area for observing this problem. The high population density of animals, raised on a relatively small floodplain area, represents one of the major sources of pollution in the bay. This paper summarizes the history of the agencies involved with the problem and presents the current approach to alleviate bacterial pollution in the bay without unduly penalizing other industries in the Tillamook basin. The paper also presents some of the legal aspects of reducing water pollution in shellfish harvesting areas and the jurisdiction of federal agencies in these matters. Finally, recommendations are given to reduce bacterial output by the major source categories in the basin, and criteria for bay closure to shellfish harvest are developed to protect the public from bacterially contaminated shellfish.

  9. Screening tests for the rapid detection of diarrhetic shellfish toxins in Washington State.

    PubMed

    Eberhart, Bich-Thuy L; Moore, Leslie K; Harrington, Neil; Adams, Nicolaus G; Borchert, Jerry; Trainer, Vera L

    2013-10-01

    The illness of three people due to diarrhetic shellfish poisoning (DSP) following their ingestion of recreationally harvested mussels from Sequim Bay State Park in the summer of 2011, resulted in intensified monitoring for diarrhetic shellfish toxins (DSTs) in Washington State. Rapid testing at remote sites was proposed as a means to provide early warning of DST events in order to protect human health and allow growers to test "pre-harvest" shellfish samples, thereby preventing harvest of toxic product that would later be destroyed or recalled. Tissue homogenates from several shellfish species collected from two sites in Sequim Bay, WA in the summer 2012, as well as other sites throughout Puget Sound, were analyzed using three rapid screening methods: a lateral flow antibody-based test strip (Jellett Rapid Test), an enzyme-linked immunosorbent assay (ELISA) and a protein phosphatase 2A inhibition assay (PP2A). The results were compared to the standard regulatory method of liquid chromatography coupled with tandem mass spectroscopy (LC-MS/MS). The Jellett Rapid Test for DSP gave an unacceptable number of false negatives due to incomplete extraction of DSTs using the manufacturer's recommended method while the ELISA antibody had low cross-reactivity with dinophysistoxin-1, the major toxin isomer in shellfish from the region. The PP2A test showed the greatest promise as a screening tool for Washington State shellfish harvesters. PMID:24084788

  10. Derivation of shellfish harvest reopening criteria following the New Carissa oil spill in Coos Bay, Oregon.

    PubMed

    Gilroy, D J

    2000-07-14

    Oil spills in Alaska, California, Maine, and other states have raised concerns regarding potential contamination of fish and shellfish, and have led to temporary closures of seafood harvests while health risks are assessed. Lacking standardized protocols, these assessments are generally ad hoc, site-specific efforts, with significant differences in risk evaluation criteria. This article describes the response of a state health agency to shellfish contamination following an oil spill on the Oregon coast, and discusses some of the factors that can complicate the evaluation of potential health risks from consumption of oil-contaminated shellfish. On 4 February 1999, the Japanese-owned cargo ship M/V New Carissa, carrying an estimated 400,000 gallons of light diesel and heavy fuel oil, ran aground 2 miles north of Coos Bay, Oregon. Damage to the ship's hull from the grounding and pounding surf caused the release of an estimated 25,000 to 70,000 gallons of oil. Concern for potential contamination of local recreational shellfish and commercial oyster beds prompted the Oregon Department of Agriculture (ODA) to close shellfish harvesting in Coos and Douglas counties. ODA requested assistance from the Oregon Health Division in the derivation of risk-based criteria for reopening the shellfish harvest. Criteria were developed for the primary contaminants of concern, polycyclic aromatic hydrocarbons (PAHs) expressed as total benzo[a]-pyrene (BaP) equivalents. "Safe" (<10 microg/kg) and "unsafe" (>45 microg/kg) BaP equivalent levels were derived based on upper end (32.5 g/d) and average (7.5 g/d) estimates of shellfish consumption, respectively. Composite samples of oysters, clams, and mussels (15-20 per composite) were collected from target areas and analyzed for PAHs by gas chromatography/mass spectroscopy (GC/MS). Carcinogenic PAHs were converted to total BaP equivalents (wet weight) and compared with criteria. Two oyster samples, collected from a slough off of Coos Bay

  11. Studies on Freezint of Shell-Fish -II

    NASA Astrophysics Data System (ADS)

    Song, Dae Jin; Konagaya, Shiro; Nakamura, Koji; Iida, Haruka; Tanaka, Takeo

    Changes in free amino acid content and compostion, and formation of odor components in ark shell Anadara broughtonii(Shrenk) during frozen storgae were studied in connection with storage temperature. The shucked shell-fish were frozen -40°C and stored at -10, -20 and -40°C, respectively for three months, and the shell flesh were subjected to anyalyses for free amino acids and odor components. The amount of total free amino acids in the shell flesh storedat -10°C was not as large as those in the flesh stored at -20 and -40°C. This finding implies that free amino acids in the shell flesh, when frozen-stored at a relatively high temperature, decrease in amount during storage and/or become liable to be lost along with drip during the course of thawing. As for respective amino acids, a mounts of Tau, β-Ala, and Gly decreased markedly, while those of Met, Leu and Ile increased to some extent. In addition, it is of particular interest that β-Ala is likely to be present in the free state. Amounts of volatile compounds such as carbonyl, nitrogenous, and sulfurous compounds have never attained the level where unpleasant or fishy odor could be percieved. However, there was a clear tendency that the higher the storage temperature, the larger amount of these compounds were presen.

  12. Removal of Paralytic Shellfish Toxins by Probiotic Lactic Acid Bacteria

    PubMed Central

    Vasama, Mari; Kumar, Himanshu; Salminen, Seppo; Haskard, Carolyn A.

    2014-01-01

    Paralytic shellfish toxins (PSTs) are non-protein neurotoxins produced by saltwater dinoflagellates and freshwater cyanobacteria. The ability of Lactobacillus rhamnosus strains GG and LC-705 (in viable and non-viable forms) to remove PSTs (saxitoxin (STX), neosaxitoxin (neoSTX), gonyautoxins 2 and 3 (GTX2/3), C-toxins 1 and 2 (C1/2)) from neutral and acidic solution (pH 7.3 and 2) was examined using HPLC. Binding decreased in the order of STX ~ neoSTX > C2 > GTX3 > GTX2 > C1. Removal of STX and neoSTX (77%–97.2%) was significantly greater than removal of GTX3 and C2 (33.3%–49.7%). There were no significant differences in toxin removal capacity between viable and non-viable forms of lactobacilli, which suggested that binding rather than metabolism is the mechanism of the removal of toxins. In general, binding was not affected by the presence of other organic molecules in solution. Importantly, this is the first study to demonstrate the ability of specific probiotic lactic bacteria to remove PSTs, particularly the most toxic PST-STX, from solution. Further, these results warrant thorough screening and assessment of safe and beneficial microbes for their usefulness in the seafood and water industries and their effectiveness in vivo. PMID:25046082

  13. Interannual variability in the timing of New England shellfish toxicity and relationships to environmental forcing.

    PubMed

    Nair, Apurva; Thomas, Andrew C; Borsuk, Mark E

    2013-03-01

    Routine monitoring along the coast of the Gulf of Maine (GoM) reveals shellfish toxicity nearly every summer, but at varying times, locations, and magnitudes. The responsible toxin is known to be produced by the dinoflagellate Alexandrium fundyense, yet there is little apparent association between Alexandrium abundance and shellfish toxicity. One possibility is that toxic cells are persistent in offshore areas and variability in shellfish toxicity is caused not by changes in overall abundance, but rather by variability in transport processes. Measurements of offshore Alexandrium biomass are scarce, so we bypass cell abundance as an explanatory variable and focus instead on the relations between shellfish toxicity and concurrent metrics of GoM meteorology, hydrology, and oceanography. While this yields over two decades (1985-2005) of data representing a variety of interannual conditions, the toxicity data are gappy in spatial and temporal coverage. We address this through a combination of parametric curve fitting and hierarchical cluster analysis to reveal eight archetypical modes of seasonal toxicity timing. Groups of locations are then formed that have similar interannual patterns in these archetypes. Finally, the interannual patterns within each group are related to available environmental metrics using classification trees. Results indicate that a weak cross-shore sea surface temperature (SST) gradient in the summer is the strongest correlate of shellfish toxicity, likely by signifying a hydrological connection between offshore Alexandrium populations and near-shore shellfish beds. High cumulative downwelling wind strength early in the season is revealed as a precursor consistent with this mechanism. Although previous studies suggest that alongshore transport is important in moving Alexandrium from the eastern to western GoM, alongshore SST gradient is not an important correlate of toxicity in our study. We conclude by discussing the implications of our results

  14. Interannual variability in the timing of New England shellfish toxicity and relationships to environmental forcing

    PubMed Central

    Nair, Apurva; Thomas, Andrew C.; Borsuk, Mark E.

    2013-01-01

    Routine monitoring along the coast of the Gulf of Maine (GoM) reveals shellfish toxicity nearly every summer, but at varying times, locations, and magnitudes. The responsible toxin is known to be produced by the dinoflagellate Alexandrium fundyense, yet there is little apparent association between Alexandrium abundance and shellfish toxicity. One possibility is that toxic cells are persistent in offshore areas and variability in shellfish toxicity is caused not by changes in overall abundance, but rather by variability in transport processes. Measurements of offshore Alexandrium biomass are scarce, so we bypass cell abundance as an explanatory variable and focus instead on the relations between shellfish toxicity and concurrent metrics of GoM meteorology, hydrology, and oceanography. While this yields over two decades (1985–2005) of data representing a variety of interannual conditions, the toxicity data are gappy in spatial and temporal coverage. We address this through a combination of parametric curve fitting and hierarchical cluster analysis to reveal eight archetypical modes of seasonal toxicity timing. Groups of locations are then formed that have similar interannual patterns in these archetypes. Finally, the interannual patterns within each group are related to available environmental metrics using classification trees. Results indicate that a weak cross-shore sea surface temperature (SST) gradient in the summer is the strongest correlate of shellfish toxicity, likely by signifying a hydrological connection between offshore Alexandrium populations and near-shore shellfish beds. High cumulative downwelling wind strength early in the season is revealed as a precursor consistent with this mechanism. Although previous studies suggest that alongshore transport is important in moving Alexandrium from the eastern to western GoM, alongshore SST gradient is not an important correlate of toxicity in our study. We conclude by discussing the implications of our

  15. Matrix effects on a cell-based assay used for the detection of paralytic shellfish toxins in bivalve shellfish samples.

    PubMed

    Aballay-Gonzalez, Ambbar; Ulloa, Viviana; Rivera, Alejandra; Hernández, Víctor; Silva, Macarena; Caprile, Teresa; Delgado-Rivera, Lorena; Astuya, Allisson

    2016-05-01

    Detecting marine biotoxins such as paralytic shellfish toxins (PSTs) is essential to ensuring the safety of seafood. The mouse bioassay is the internationally accepted method for monitoring PSTs, but technical and ethical issues have led to a search for new detection methods. The mouse neuroblastoma cell-based assay (Neuro-2a CBA) using ouabain and veratridine (O/V) has proven useful for the detection of PSTs. However, CBAs are sensitive to shellfish-associated matrix interferences. As the extraction method highly influences matrix interferences, this study compared three extraction protocols: Association of Official Analytical Chemists (AOAC) 2005.06, AOAC 2011.02 and an alternative liquid-liquid method. These methods were used to assess the matrix effect of extracts from four commercially important bivalve species (Chilean mussel, Magellan mussel, clam and Pacific oyster) in Neuro-2a CBA. Extracts from all three protocols caused a toxic effect in Neuro-2a cells (without O/V) when tested at a concentration of 25 mg of tissue-equivalent (TE) ml(-1). The greatest toxicity was obtained through the AOAC 2011.02 protocol, especially for the Chilean mussel and Pacific oyster extracts. Similar toxicity levels (less than 15%) were observed in all extracts at 3.1 mg TE ml(-1). When assessed in Neuro-2a CBA, AOAC 2005.06 extracts presented the lowest matrix interferences, while the highest interferences were observed for AOAC 2011.02 in Magellan mussel and clam extracts. Finally, the AOAC 2005.06 and alternative protocols were compared using Chilean mussel samples fortified with 40 and 80 µg STX per 100 g meat. The AOAC 2005.06 method demonstrated better results. In conclusion, the AOAC 2005.06 extracts exhibited the fewest interferences in the Neuro-2a CBA. Therefore, this extraction method should be considered for the implementation of Neuro-2a CBA as a high-throughput screening methodology for PST detection. PMID:27002718

  16. Investigation of diarrhetic shellfish toxins in Lingshan Bay, Yellow Sea, China, using solid-phase adsorption toxin tracking (SPATT).

    PubMed

    Li, Feng-Ling; Li, Zhao-Xin; Guo, Meng-Meng; Wu, Hai-Yan; Zhang, Ting-Ting; Song, Cai-Hu

    2016-08-01

    Early detection of toxin contamination in shellfish (i.e., prior to harvest) would be of considerable advantage to fish farmers, researchers and food safety administrators. In 2004, a solid-phase adsorption toxin tracking (SPATT) technique was developed to study algal toxins in New Zealand shellfish harvesting areas. In subsequent years, the basic idea have been further developed. Using a SPATT method, an investigation into diarrhetic shellfish toxins (DSTs) was conducted over a 10.5-month period in 2012 in shellfish farming areas in Lingshan Bay (Yellow Sea, China). This paper discusses the relationship among DSTs in toxic algae, seawater and contaminated shellfish. OA, DTX1 and PTX2 toxins were found in this shellfish farming area from summer to autumn. In shellfish the maximum concentrations of OA and DTX1 were 81 and 41 ng g(-1) respectively. PTX2 was very low. The maximum levels of OA and DTX1 in seawater were 165 and 56 ng g(-1) respectively, and were detected on June, separated by a 14-day period. Shellfish had accumulated the highest levels of OA and DTX1 recorded in this study. Comparison of the variations in DST levels in seawater showed there to be about 2 weeks for administrators to warn of the potential for toxin contamination in shellfish. Further research to explore the relationship between the variables of seawater temperature, sunlight and salinity, and DSTs in shellfish may help to establish a more suitable model for forecasting DST contamination in shellfish. PMID:27295385

  17. Neurotoxic shellfish poisoning and brevetoxin metabolites: a case study from Florida.

    PubMed

    Poli, M A; Musser, S M; Dickey, R W; Eilers, P P; Hall, S

    2000-07-01

    In June of 1996, three family members were diagnosed as suffering from neurotoxic shellfish poisoning (NSP) as a result of eating shellfish harvested from Sarasota Bay, Florida. Urine from two of these patients and extracts of shellfish collected from the same location were analyzed by radioimmunoassay (RIA) and by receptor binding assay. Activity consistent with brevetoxins was present in both urine and shellfish extracts. High performance liquid chromatographic (HPLC) analysis of shellfish extracts demonstrated multiple fractions recognized by specific anti-brevetoxin antibodies, suggesting metabolic conversion of parent brevetoxins. Affinity-purification of these extracts yielded four major peaks of activity. One peak was identified by HPLC-mass spectroscopy (HPLC-MS) to be PbTx-3, which was likely produced metabolically from the dominant parent toxin PbTx-2. No PbTx-2, however, was detected. Other peaks of activity were determined to consist of compounds of apparent masses of [M + H]+ of 1018, 1034, and 1005. These higher masses are suggestive of conjugated metabolites, but their structures have yet to be determined. The material associated with these latter three peaks were recognized by both RIA and receptor binding assay, but they quantitated differently. This finding suggests that these metabolites react differently in the two assays, and this result may have important implications for seafood safety and regulation. We suggest these metabolites to be the true cause of NSP, and they should be taken into account during regulatory testing. PMID:10728835

  18. Occurrence and profiles of lipophilic toxins in shellfish harvested from Argentina.

    PubMed

    Turner, Andrew D; Goya, Alejandra B

    2015-08-01

    The presence of phytoplankton responsible for the production of lipophilic marine biotoxins is well recognised throughout parts of South America. To date, the quantitation of lipophilic toxins in Argentinean shellfish has been limited to select and highly focussed geographical studies. This work reports the analysis for lipophilic marine biotoxins in shellfish harvested across five regions of Argentina between 1992 and 2012. LC-MS/MS analysis was used for the quantitation of all regulated lipophilic toxins. High concentrations of okadaic acid group toxins were quantified, with a clear dominance of the parent okadaic acid and more than 90% of the toxin present as esters. Results showed DSP toxins in shellfish from the Buenos Aires Province during 2006 and 2007, earlier than previously described. There was also strong evidence linking the presence of okadaic acid to human intoxications. Other lipophilic toxins detected were yessotoxin, pectenotoxin-2 and 13-desMeC spirolide. With evidence published recently for the presence of azaspiracid producers, this work reports the detection of low concentrations of azaspiracid-2 in shellfish. As such the data provides the first published evidence for yessotoxins and azaspiracids in Argentinean shellfish and further evidence for the continuing presence of lipophilic marine toxins in Argentinean waters. PMID:26003796

  19. Human intoxication with paralytic shellfish toxins: clinical parameters and toxin analysis in plasma and urine.

    PubMed

    García, Carlos; Lagos, Marcelo; Truan, Dominique; Lattes, Karinna; Véjar, Omar; Chamorro, Beatriz; Iglesias, Verónica; Andrinolo, Darío; Lagos, Néstor

    2005-01-01

    This study reports the data recorded from four patients intoxicated with shellfish during the summer 2002, after consuming ribbed mussels (Aulacomya ater) with paralytic shellfish toxin contents of 8,066 +/- 61.37 microg/100 gr of tissue. Data associated with clinical variables and paralytic shellfish toxins analysis in plasma and urine of the intoxicated patients are shown. For this purpose, the evolution of respiratory frequency, arterial blood pressure and heart rate of the poisoned patients were followed and recorded. The clinical treatment to reach a clinically stable condition and return to normal physiological parameters was a combination of hydration with saline solution supplemented with Dobutamine (vasoactive drug), Furosemide (diuretic) and Ranitidine (inhibitor of acid secretion). The physiological condition of patients began to improve after four hours of clinical treatment, and a stable condition was reached between 12 to 24 hours. The HPLC-FLD analysis showed only the GTX3/GTX2 epimers in the blood and urine samples. Also, these epimers were the only paralytic shellfish toxins found in the shellfish extract sample. PMID:16238098

  20. Exxon Valdez oil spill. State/federal natural resource damage assessment final report. Impacts of the Exxon Valdez oil spill on bottomfish and shellfish in Prince William Sound. Fish/shellfish study 18

    SciTech Connect

    1995-05-01

    Trawl surveys were conducted in Prince William Sound and adjacent waters in 1989 and 1990 to assess impacts of the Exxon Valdex oil spill on commercial species of bottomfish and shellfish. The surveys (1) determined abundance, distribution, and year-class strength of important bottomfish and shellfish species and (2) assessed the incidence and distribution of oil contamination in fish bile.

  1. Probiotics in fish and shellfish culture: immunomodulatory and ecophysiological responses.

    PubMed

    C De, Bidhan; Meena, D K; Behera, B K; Das, Pronob; Das Mohapatra, P K; Sharma, A P

    2014-06-01

    Aquaculture is emerging as one of the most viable and promising enterprises for keeping pace with the surging need for animal protein, providing nutritional and food security to humans, particularly those residing in regions where livestock is relatively scarce. With every step toward intensification of aquaculture practices, there is an increase in the stress level in the animal as well as the environment. Hence, disease outbreak is being increasingly recognized as one of the most important constraints to aquaculture production in many countries, including India. Conventionally, the disease control in aquaculture has relied on the use of chemical compounds and antibiotics. The development of non-antibiotic and environmentally friendly agents is one of the key factors for health management in aquaculture. Consequently, with the emerging need for environmentally friendly aquaculture, the use of alternatives to antibiotic growth promoters in fish nutrition is now widely accepted. In recent years, probiotics have taken center stage and are being used as an unconventional approach that has numerous beneficial effects in fish and shellfish culture: improved activity of gastrointestinal microbiota and enhanced immune status, disease resistance, survival, feed utilization and growth performance. As natural products, probiotics have much potential to increase the efficiency and sustainability of aquaculture production. Therefore, comprehensive research to fully characterize the intestinal microbiota of prominent fish species, mechanisms of action of probiotics and their effects on the intestinal ecosystem, immunity, fish health and performance is reasonable. This review highlights the classifications and applications of probiotics in aquaculture. The review also summarizes the advancement and research highlights of the probiotic status and mode of action, which are of great significance from an ecofriendly, sustainable, intensive aquaculture point of view. PMID:24419543

  2. A competitive ELISA to detect brevetoxins from Karenia brevis (formerly Gymnodinium breve) in seawater, shellfish, and mammalian body fluid.

    PubMed Central

    Naar, Jerome; Bourdelais, Andrea; Tomas, Carmelo; Kubanek, Julia; Whitney, Philip L; Flewelling, Leanne; Steidinger, Karen; Lancaster, Johnny; Baden, Daniel G

    2002-01-01

    We developed a competitive enzyme-linked immunosorbent assay (ELISA) to analyze brevetoxins, using goat anti-brevetoxin antibodies obtained after immunization with keyhole limpet hemocyanin-brevetoxin conjugates, in combination with a three-step signal amplification process. The procedure, which used secondary biotinylated antibodies, streptavidine-horseradish peroxidase conjugate, and chromogenic enzyme substrate, was useful in reducing nonspecific background signals commonly observed with complex matrices. This competitive ELISA detected brevetoxins in seawater, shellfish extract and homogenate, and mammalian body fluid such as urine and serum without pretreatment, dilution, or purification. We investigated the application of this technique for shellfish monitoring by spiking shellfish meat with brevetoxins and by analyzing oysters from two commercial shellfish beds in Florida that were exposed to a bloom of Karenia brevis (formerly Gymnodinium breve). We performed brevetoxin analysis of shellfish extracts and homogenates by ELISA and compared it with the mouse bioassay and receptor binding assay. The detection limit for brevetoxins in spiked oysters was 2.5 microg/100 g shellfish meat. This assay appears to be a useful tool for neurotoxic shellfish poisoning monitoring in shellfish and seawater, and for mammalian exposure diagnostics, and significantly reduces the time required for analyses. PMID:11836147

  3. Formation of a volunteer harmful algal bloom network in British Columbia, Canada, following an outbreak of diarrhetic shellfish poisoning.

    PubMed

    McIntyre, Lorraine; Cassis, David; Haigh, Nicola

    2013-11-01

    Evidence for shellfish toxin illness in British Columbia (BC) on the west coast of Canada can be traced back to 1793. For over two hundred years, domestically acquired bivalve shellfish toxin illnesses in BC were solely ascribed to paralytic shellfish poisonings caused by algal blooms of Alexandrium. This changed in 2011, when BC experienced its first outbreak of diarrhetic shellfish poisoning (DSP). As a result of this outbreak, Canada's first DSP symposium was held in November, 2012, in North Vancouver, BC. Three of the objectives of the symposium were to provide a forum to educate key stakeholders on this emerging issue, to identify research and surveillance priorities and to create a DSP network. The purpose of this paper is to review what is known about shellfish poisoning in BC and to describe a novel volunteer network that arose following the symposium. The newly formed network was designed for industry shellfish growers to identify harmful algae bloom events, so that they may take actions to mitigate the effects of harmful blooms on shellfish morbidity. The network will also inform public health and regulatory stakeholders of potentially emerging issues in shellfish growing areas. PMID:24172211

  4. Prevalence and Characterization of Shiga Toxin-Producing and Enteropathogenic Escherichia coli in Shellfish-Harvesting Areas and Their Watersheds

    PubMed Central

    Balière, Charlotte; Rincé, Alain; Blanco, Jorge; Dahbi, Ghizlane; Harel, Josée; Vogeleer, Philippe; Giard, Jean-Christophe; Mariani-Kurkdjian, Patricia; Gourmelon, Michèle

    2015-01-01

    more strains formed a strong biofilm at 18 than at 30°C. Finally, more than 85% of analyzed strains were found to be sensitive to the 16 tested antibiotics. These data suggest the low risk of human infection by STEC if shellfish from these shellfish-harvesting areas were consumed. PMID:26648928

  5. Formation of a Volunteer Harmful Algal Bloom Network in British Columbia, Canada, Following an Outbreak of Diarrhetic Shellfish Poisoning

    PubMed Central

    McIntyre, Lorraine; Cassis, David; Haigh, Nicola

    2013-01-01

    Evidence for shellfish toxin illness in British Columbia (BC) on the west coast of Canada can be traced back to 1793. For over two hundred years, domestically acquired bivalve shellfish toxin illnesses in BC were solely ascribed to paralytic shellfish poisonings caused by algal blooms of Alexandrium. This changed in 2011, when BC experienced its first outbreak of diarrhetic shellfish poisoning (DSP). As a result of this outbreak, Canada’s first DSP symposium was held in November, 2012, in North Vancouver, BC. Three of the objectives of the symposium were to provide a forum to educate key stakeholders on this emerging issue, to identify research and surveillance priorities and to create a DSP network. The purpose of this paper is to review what is known about shellfish poisoning in BC and to describe a novel volunteer network that arose following the symposium. The newly formed network was designed for industry shellfish growers to identify harmful algae bloom events, so that they may take actions to mitigate the effects of harmful blooms on shellfish morbidity. The network will also inform public health and regulatory stakeholders of potentially emerging issues in shellfish growing areas. PMID:24172211

  6. Recent innovation in microbial source tracking using bacterial real-time PCR markers in shellfish.

    PubMed

    Mauffret, A; Mieszkin, S; Morizur, M; Alfiansah, Y; Lozach, S; Gourmelon, M

    2013-03-15

    We assessed the capacity of real-time PCR markers to identify the origin of contamination in shellfish. Oyster, cockles or clams were either contaminated with fecal materials and host-associated markers designed from Bacteroidales or Catellicoccus marimammalium 16S RNA genes were extracted from their intravalvular liquid, digestive tissues or shellfish flesh. Extraction of bacterial DNA from the oyster intravalvular liquid with FastDNA spin kit for soil enabled the selected markers to be quantified in 100% of artificially contaminated samples, and the source of contamination to be identified in 13 out of 38 naturally contaminated batches from European Class B and Class C areas. However, this protocol did not enable the origin of the contamination to be identified in cockle or clam samples. Although results are promising for extracts from intravalvular liquid in oyster, it is unlikely that a single protocol could be the best across all bacterial markers and types of shellfish. PMID:23398745

  7. Effect of the Clean Water Act on shellfish growing waters in the Gulf of Mexico

    SciTech Connect

    Broutman, M.A.

    1988-01-01

    This report examines the classification of shellfish growing waters in the Gulf of Mexico as an indicator of bacterial water quality. Information presented includes the status of classified waters, sources of pollution affecting waters that are not classified as approved, and trends in classification between 1971 and 1985. Data were collected by site visits to the five Gulf states, interviews with state personnel, and reference to written materials. Data are used to assess the effectiveness of national efforts to improve bacterial water quality in the past fifteen years since passage of the Clean Water Act. The hypothesis to be tested is that these efforts have not succeeded in reducing fecal coliform concentrations to levels required for approved harvest of shellfish, as established by the National Shellfish Sanitation Program.

  8. Relating the bivalve shellfish harvesting area classification criteria in the United States and European Union programmes.

    PubMed

    Lee, R J; Reese, R A

    2014-06-01

    Estimation of the level of risk of faecal contamination of shellfish harvesting areas is undertaken by monitoring faecal indicator bacteria in seawater samples under the United States programme and shellfish flesh samples under the European Union (EU) programme. Determining the relationship between the two approaches is important for assessing the relative level of public health protection and regulating international trade. The relationship was investigated using both statistical modelling and simple compliance assessment on large international data sets of paired seawater and shellfish samples. The two approaches yielded the same conclusions: EU class A is more stringent than the US Approved category for all species; the US Restrictive standard is more restrictive than EU class B for some bivalve species. Therefore, the classifications under the two programmes are not exactly equivalent. PMID:24937222

  9. Evaluation of mouse bioassay results in an inter-laboratory comparison for paralytic shellfish poisoning toxins

    NASA Astrophysics Data System (ADS)

    Cao, Jijuan; Zheng, Jiang; Yu, Bing; Wang, Qiuyan; Xu, Junyi; Li, Aifeng

    2011-07-01

    An inter-laboratory comparison of the AOAC mouse bioassay for paralytic shellfish poisoning (PSP) toxicity in shellfish was carried out among 25 Chinese laboratories to examine the overall performance for PSP testing in China, and to analyze the main factors affecting the performance of this method. The toxic scallop Patinopecten yessoensis collected from coast of Bohai Sea, China, was used as a test sample in the comparison study. The results were reported and evaluated using robust statistical methods. The z scores showed that 80%, 8%, and 12% of laboratories reported satisfactory results, unsatisfactory results, and questionable results, respectively. This evaluation demonstrates that the PSP mouse bioassay is an appropriate method for screening and testing PSP toxicity in shellfish. However, it was found that the experience and skill of technicians, as well as the body weight and health status of mice being used significantly affected the accuracy of the method.

  10. Shellfish and residual chemical contaminants: hazards, monitoring, and health risk assessment along French coasts.

    PubMed

    Guéguen, Marielle; Amiard, Jean-Claude; Arnich, Nathalie; Badot, Pierre-Marie; Claisse, Didier; Guérin, Thierry; Vernoux, Jean-Paul

    2011-01-01

    In this review, we address the identification of residual chemical hazards in shellfish collected from the marine environment or in marketed shellfish. Data, assembled on the concentration of contaminants detected, were compared with the appropriate regulatory and food safety standards. Moreover, data on human exposure and body burden levels were evaluated in the context of potential health risks.Shellfish farming is a common industry along European coasts. The primary types of shellfish consumed in France are oysters, mussels, king scallops, winkles,whelks, cockles, clams, and other scallops. Shellfish filter large volumes of water to extract their food and are excellent bioaccumulators. Metals and other pollutants that exist in the marine environment partition into particular organs, according to their individual chemical characteristics. In shellfish, accumulation often occurs in the digestive gland, which plays a role in assimilation, excretion, and detoxification of contaminants. The concentrations of chemical contaminants in bivalve mollusks are known to fluctuate with the seasons.European regulations limit the amount and type of contaminants that can appear in foodstuffs. Current European standards regulate the levels of micro-biological agents, phycotoxins, and some chemical contaminants in food. Since 2006, these regulations have been compiled into the "Hygiene Package." Bivalve mollusks must comply with maximum levels of certain contaminants as follows:lead (1.5 mg kg-1), cadmium (1 mg kg-1), mercury (0.5 mg kg-1), dioxins (4 pg g-1 and dioxins + DL-PCBs 8 pg g-1), and benzo[a]pyrene (10 μp.g kg-1).In this review, we identify the levels of major contaminants that exist in shellfish(collected from the marine environment and/or in marketed shellfish). The follow-ing contaminants are among those that are profiled: Cd, Pb, Hg, As, Ni, Cr, V,Mn, Cu, Zn, Co, Se, Mg, Mo, radionuclides, benzo[a]pyrene, PCBs, dioxins and furans, PAHs, TBT, HCB, dieldrin, DDT

  11. Diarrhetic Shellfish Toxins and Other Lipophilic Toxins of Human Health Concern in Washington State

    PubMed Central

    Trainer, Vera L.; Moore, Leslie; Bill, Brian D.; Adams, Nicolaus G.; Harrington, Neil; Borchert, Jerry; da Silva, Denis A. M.; Eberhart, Bich-Thuy L.

    2013-01-01

    The illness of three people in 2011 after their ingestion of mussels collected from Sequim Bay State Park, Washington State, USA, demonstrated the need to monitor diarrhetic shellfish toxins (DSTs) in Washington State for the protection of human health. Following these cases of diarrhetic shellfish poisoning, monitoring for DSTs in Washington State became formalized in 2012, guided by routine monitoring of Dinophysis species by the SoundToxins program in Puget Sound and the Olympic Region Harmful Algal Bloom (ORHAB) partnership on the outer Washington State coast. Here we show that the DSTs at concentrations above the guidance level of 16 μg okadaic acid (OA) + dinophysistoxins (DTXs)/100 g shellfish tissue were widespread in sentinel mussels throughout Puget Sound in summer 2012 and included harvest closures of California mussel, varnish clam, manila clam and Pacific oyster. Concentrations of toxins in Pacific oyster and manila clam were often at least half those measured in blue mussels at the same site. The primary toxin isomer in shellfish and plankton samples was dinophysistoxin-1 (DTX-1) with D. acuminata as the primary Dinophysis species. Other lipophilic toxins in shellfish were pectenotoxin-2 (PTX-2) and yessotoxin (YTX) with azaspiracid-2 (AZA-2) also measured in phytoplankton samples. Okadaic acid, azaspiracid-1 (AZA-1) and azaspiracid-3 (AZA-3) were all below the levels of detection by liquid chromatography tandem mass spectrometry (LC-MS/MS). A shellfish closure at Ruby Beach, Washington, was the first ever noted on the Washington State Pacific coast due to DSTs. The greater than average Fraser River flow during the summers of 2011 and 2012 may have provided an environment conducive to dinoflagellates and played a role in the prevalence of toxigenic Dinophysis in Puget Sound. PMID:23760013

  12. Warm temperature acclimation impacts metabolism of paralytic shellfish toxins from Alexandrium minutum in commercial oysters.

    PubMed

    Farrell, Hazel; Seebacher, Frank; O'Connor, Wayne; Zammit, Anthony; Harwood, D Tim; Murray, Shauna

    2015-09-01

    Species of Alexandrium produce potent neurotoxins termed paralytic shellfish toxins and are expanding their ranges worldwide, concurrent with increases in sea surface temperature. The metabolism of molluscs is temperature dependent, and increases in ocean temperature may influence both the abundance and distribution of Alexandrium and the dynamics of toxin uptake and depuration in shellfish. Here, we conducted a large-scale study of the effect of temperature on the uptake and depuration of paralytic shellfish toxins in three commercial oysters (Saccostrea glomerata and diploid and triploid Crassostrea gigas, n = 252 per species/ploidy level). Oysters were acclimated to two constant temperatures, reflecting current and predicted climate scenarios (22 and 27 °C), and fed a diet including the paralytic shellfish toxin-producing species Alexandrium minutum. While the oysters fed on A. minutum in similar quantities, concentrations of the toxin analogue GTX1,4 were significantly lower in warm-acclimated S. glomerata and diploid C. gigas after 12 days. Following exposure to A. minutum, toxicity of triploid C. gigas was not affected by temperature. Generally, detoxification rates were reduced in warm-acclimated oysters. The routine metabolism of the oysters was not affected by the toxins, but a significant effect was found at a cellular level in diploid C. gigas. The increasing incidences of Alexandrium blooms worldwide are a challenge for shellfish food safety regulation. Our findings indicate that rising ocean temperatures may reduce paralytic shellfish toxin accumulation in two of the three oyster types; however, they may persist for longer periods in oyster tissue. PMID:26032975

  13. Diarrhetic shellfish toxins and other lipophilic toxins of human health concern in Washington State.

    PubMed

    Trainer, Vera L; Moore, Leslie; Bill, Brian D; Adams, Nicolaus G; Harrington, Neil; Borchert, Jerry; da Silva, Denis A M; Eberhart, Bich-Thuy L

    2013-06-01

    The illness of three people in 2011 after their ingestion of mussels collected from Sequim Bay State Park, Washington State, USA, demonstrated the need to monitor diarrhetic shellfish toxins (DSTs) in Washington State for the protection of human health. Following these cases of diarrhetic shellfish poisoning, monitoring for DSTs in Washington State became formalized in 2012, guided by routine monitoring of Dinophysis species by the SoundToxins program in Puget Sound and the Olympic Region Harmful Algal Bloom (ORHAB) partnership on the outer Washington State coast. Here we show that the DSTs at concentrations above the guidance level of 16 μg okadaic acid (OA) + dinophysistoxins (DTXs)/100 g shellfish tissue were widespread in sentinel mussels throughout Puget Sound in summer 2012 and included harvest closures of California mussel, varnish clam, manila clam and Pacific oyster. Concentrations of toxins in Pacific oyster and manila clam were often at least half those measured in blue mussels at the same site. The primary toxin isomer in shellfish and plankton samples was dinophysistoxin-1 (DTX-1) with D. acuminata as the primary Dinophysis species. Other lipophilic toxins in shellfish were pectenotoxin-2 (PTX-2) and yessotoxin (YTX) with azaspiracid-2 (AZA-2) also measured in phytoplankton samples. Okadaic acid, azaspiracid-1 (AZA-1) and azaspiracid-3 (AZA-3) were all below the levels of detection by liquid chromatography tandem mass spectrometry (LC-MS/MS). A shellfish closure at Ruby Beach, Washington, was the first ever noted on the Washington State Pacific coast due to DSTs. The greater than average Fraser River flow during the summers of 2011 and 2012 may have provided an environment conducive to dinoflagellates and played a role in the prevalence of toxigenic Dinophysis in Puget Sound. PMID:23760013

  14. TRPV1 as a key determinant in ciguatera and neurotoxic shellfish poisoning

    PubMed Central

    Cuypers, Eva; Yanagihara, Angel; Rainier, Jon D.; Tytgat, Jan

    2007-01-01

    Ciguatera fish poisoning and neurotoxic shellfish poisoning are distinct clinical entities characterized by gastrointestinal and neurological disturbances, following the consumption of certain reef fish and shellfish containing toxic polyether compounds sporadically present in certain toxic marine dinoflagellates. The biotransformation and bioaccumulation of gambierol and brevetoxin, and their congeners, are believed to be involved in the pathogenesis of these “food-chain diseases”, for which no effective treatments are available. Here, we describe for the first time the potent effect of gambierol and brevetoxin on TRPV1 channels, a key player in thermal and pain sensation. Our findings may lead to promising new therapeutic interventions. PMID:17659256

  15. Outbreak of Diarrhetic Shellfish Poisoning Associated with Mussels, British Columbia, Canada

    PubMed Central

    Taylor, Marsha; McIntyre, Lorraine; Ritson, Mark; Stone, Jason; Bronson, Roni; Bitzikos, Olga; Rourke, Wade; Galanis, Eleni

    2013-01-01

    In 2011, a Diarrhetic Shellfish Poisoning (DSP) outbreak occurred in British Columbia (BC), Canada that was associated with cooked mussel consumption. This is the first reported DSP outbreak in BC. Investigation of ill individuals, traceback of product and laboratory testing for toxins were used in this investigation. Sixty-two illnesses were reported. Public health and food safety investigation identified a common food source and harvest area. Public health and regulatory agencies took actions to recall product and notify the public. Shellfish monitoring program changes were implemented after the outbreak. Improved response and understanding of toxin production will improve management of future DSP outbreaks. PMID:23697950

  16. Shellfish allergy and relation to iodinated contrast media: United Kingdom survey

    PubMed Central

    Baig, Mudassar; Farag, Ahmad; Sajid, Jamal; Potluri, Rahul; Irwin, R Bruce; Khalid, Hafiz Mohammed Idrees

    2014-01-01

    AIM: To assess current practice of United Kingdom cardiologists with respect to patients with reported shellfish/iodine allergy, and in particular the use of iodinated contrast for elective coronary angiography. Moreover we have reviewed the current evidence-base and guidelines available in this area. METHODS: A questionnaire survey was send to 500 senior United Kingdom cardiologists (almost 50% cardiologists registered with British Cardiovascular Society) using email and first 100 responses used to analyze practise. We involved cardiologists performing coronary angiograms routinely both at secondary and tertiary centres. Three specific questions relating to allergy were asked: (1) History of shellfish/iodine allergy in pre-angiography assessment; (2) Treatments offered for shellfish/iodine allergy individuals; and (3) Any specific treatment protocol for shellfish/iodine allergy cases. We aimed to establish routine practice in United Kingdom for patients undergoing elective coronary angiography. We also performed comprehensive PubMed search for the available evidence of relationship between shellfish/iodine allergy and contrast media. RESULTS: A total of 100 responses were received, representing 20% of all United Kingdom cardiologists. Ninety-three replies were received from consultant cardiologists, 4 from non-consultant grades and 3 from cardiology specialist nurses. Amongst the respondents, 66% routinely asked about a previous history of shellfish/iodine allergy. Fifty-six percent would pre-treat these patients with steroids and anti-histamines. The other 44% do nothing, or do nonspecific testing based on their personal experience as following: (1) Skin test with 1 mL of subcutaneous contrast before intravenous contrast; (2) Test dose 2 mL contrast before coronary injection; (3) Close observation for shellfish allergy patients; and (4) Minimal evidence that the steroid and anti-histamine regime is effective but it makes us feel better. CONCLUSION: There is no

  17. Trace metal content of fish and shellfishes of the Niger delta area of Nigeria

    SciTech Connect

    Kakulu, S.E.; Osibanjo, O.; Ajayi, S.O.

    1987-01-01

    The trace metal contents of various fish and shellfishes from the Niger delta area of Nigeria were determined. The levels in the shellfishes were higher than those in the fish, which could be due to their being bottom feeders. The levels of fish varied from <0.01-0.10 ..mu..g/g for Cd, < 0.05-3.69 ..mu..g/g for Cu, 0.49-16.52 ..mu..g/g for Fe, and 0.08-6.90 ..mu..g/g for Zn. 15 references, 1 figures, 2 tables.

  18. Shellfish depuration by gamma irradiation. Progress report No. 1, October 1, 1985-July 25, 1986

    SciTech Connect

    Beghian, L.; Melnick, J.

    1986-07-25

    Objective is to investigate the feasibility of employing food irradiation technology to reduce or eliminate the threat of viral diseases contracted as a result of consumption of raw or inadequately cooked shellfish. Several recently published studies warn of the health risks associated with eating of raw shellfish - particularly American oysters, Crassostrea virginica, and the hardshelled clam, Mercenaria mercenaria. This study addresses the possibility of reducing the incidence of molluscanborne diseases through the application of /sup 60/Co gamma irradiation processing to effect the inactivation of pathogenic viruses in live, raw shwllfish. Dosimetry, D/sub 10/ doses, and organoleptic effects were studied.

  19. Disease management strategies for shellfish aquaculture: the important role of hatcheries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disease management is a critical component of the successful production of bivalves. Infections by bacterial pathogens can cause rapid mortality of shellfish larvae with devastating consequences for both the hatcheries and the farmers that rely upon them. Furthermore, several bacterial and parasiti...

  20. Distribution of Marine Lipophilic Toxins in Shellfish Products Collected from the Chinese Market

    PubMed Central

    Wu, Haiyan; Yao, Jianhua; Guo, Mengmeng; Tan, Zhijun; Zhou, Deqing; Zhai, Yuxiu

    2015-01-01

    To investigate the prevalence of lipophilic marine biotoxins in shellfish from the Chinese market, we used hydrophilic interaction liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure levels of okadaic acid (OA), azaspiracid (AZA1), pectenotoxin (PTX2), gymnodimine (GYM), and spirolide (SPX1). We collected and analyzed 291 shellfish samples from main production sites along a wide latitudinal transect along the Chinese coastline from December 2008 to December 2009. Results revealed a patchy distribution of the five toxins and highlighted the specific geographical distribution and seasonal and species variation of the putative toxigenic organisms. All five lipophilic marine biotoxins were found in shellfish samples. The highest concentrations of OA, AZA1, PTX2, GYM, and SPX1 were 37.3, 5.90, 16.4, 14.4, and 8.97 μg/kg, respectively. These values were much lower than the legislation limits for lipophilic shellfish toxins. However, the value might be significantly underestimated for the limited detection toxins. Also, these toxins were found in most coastal areas of China and were present in almost all seasons of the year. Thus, these five toxins represent a potential threat to human health. Consequently, studies should be conducted and measures should be taken to ensure the safety of the harvested product. PMID:26184236

  1. Distribution of Marine Lipophilic Toxins in Shellfish Products Collected from the Chinese Market.

    PubMed

    Wu, Haiyan; Yao, Jianhua; Guo, Mengmeng; Tan, Zhijun; Zhou, Deqing; Zhai, Yuxiu

    2015-07-01

    To investigate the prevalence of lipophilic marine biotoxins in shellfish from the Chinese market, we used hydrophilic interaction liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure levels of okadaic acid (OA), azaspiracid (AZA1), pectenotoxin (PTX2), gymnodimine (GYM), and spirolide (SPX1). We collected and analyzed 291 shellfish samples from main production sites along a wide latitudinal transect along the Chinese coastline from December 2008 to December 2009. Results revealed a patchy distribution of the five toxins and highlighted the specific geographical distribution and seasonal and species variation of the putative toxigenic organisms. All five lipophilic marine biotoxins were found in shellfish samples. The highest concentrations of OA, AZA1, PTX2, GYM, and SPX1 were 37.3, 5.90, 16.4, 14.4, and 8.97 μg/kg, respectively. These values were much lower than the legislation limits for lipophilic shellfish toxins. However, the value might be significantly underestimated for the limited detection toxins. Also, these toxins were found in most coastal areas of China and were present in almost all seasons of the year. Thus, these five toxins represent a potential threat to human health. Consequently, studies should be conducted and measures should be taken to ensure the safety of the harvested product. PMID:26184236

  2. New perspectives on virus detection in shellfish: hemocytes as a source of concentrated virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    USDA ARS research indicates that circulating phagocytic cells (hemocytes) within oysters retain virus particles. We find that persistence of hepatitis A virus (HAV) within oyster hemocytes correlates with the presence of virus within whole oysters. Since bivalve shellfish have no self-nonself immun...

  3. 76 FR 65200 - Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: Request for Comments and for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ...The Food and Drug Administration (FDA) is undertaking a collaboration with Health Canada, the Canadian Food Inspection Agency, Environment Canada, and Fisheries and Oceans Canada, to conduct a quantitative food safety risk assessment on norovirus in bivalve molluscan shellfish, specifically, oysters, clams, and mussels. FDA, on behalf of the collaborative team, is requesting submission of......

  4. Shellfish-associated enteric virus illness: virus localization, disease outbreaks and prevention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous outbreaks of shellfish-borne enteric virus illness have been reported worldwide. Most notable among the outbreaks are those involving norovirus illness and hepatitis A. Lessons learned from outbreak investigations indicate that most outbreaks are preventable. Anthropogenic sources of con...

  5. Occurrence of Lipophilic Marine Toxins in Shellfish from Galicia (NW of Spain) and Synergies among Them

    PubMed Central

    Rodríguez, Laura P.; González, Virginia; Martínez, Aníbal; Paz, Beatriz; Lago, Jorge; Cordeiro, Victoria; Blanco, Lucía; Vieites, Juan Manuel; Cabado, Ana G.

    2015-01-01

    Lipophilic marine toxins pose a serious threat for consumers and an enormous economic problem for shellfish producers. Synergistic interaction among toxins may play an important role in the toxicity of shellfish and consequently in human intoxications. In order to study the toxic profile of molluscs, sampled during toxic episodes occurring in different locations in Galicia in 2014, shellfish were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS), the official method for the detection of lipophilic toxins. The performance of this procedure was demonstrated to be fit for purpose and was validated in house following European guidelines. The vast majority of toxins present in shellfish belonged to the okadaic acid (OA) group and some samples from a particular area contained yessotoxin (YTX). Since these toxins occur very often with other lipophilic toxins, we evaluated the potential interactions among them. A human neuroblastoma cell line was used to study the possible synergies of OA with other lipophilic toxins. Results show that combination of OA with dinophysistoxin 2 (DTX2) or YTX enhances the toxicity triggered by OA, decreasing cell viability and cell proliferation, depending on the toxin concentration and incubation time. The effects of other lipophilic toxins as 13-desmethyl Spirolide C were also evaluated in vitro. PMID:25815891

  6. Fluorogenic membrane overlays to enumerate total coliforms, Escherichia coli, and total Vibrionaceae in shellfish and seawater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three assays were developed to enumerate total coliforms, Escherichia coli, and total Vibrionaceae in shellfish and other foods and in seawater and other environmental samples. Assays involve membrane overlays of overnight colonies on non-selective agar plates to detect ß-glucuronidase and lysyl am...

  7. High pressure processing as an intervention for raw virus-contaminated shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past 7 years, the USDA ARS Seafood Safety Laboratory has evaluated the potential use of high pressure processing (HPP) as a processing strategy for virus-contaminated shellfish. HPP can inactivate hepatitis A virus, (HAV), the human norovirus surrogates feline calicivirus and murine norovi...

  8. 78 FR 22366 - Proposed Information Collection (Purchase of Shellfish) Activity: Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-15

    ... AFFAIRS Proposed Information Collection (Purchase of Shellfish) Activity: Comment Request AGENCY: Office... information through Federal Docket Management System ] (FDMS) at www.Regulations.gov ; or Sylvester Rainey, OA.... 104-13; 44 U.S.C. 3501-3521), Federal agencies must obtain approval from the Office of Management...

  9. 75 FR 13211 - Proposed Information Collection (Purchase of Shellfish) Activity: Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ... AFFAIRS Proposed Information Collection (Purchase of Shellfish) Activity: Comment Request AGENCY: Office... information through Federal Docket Management System (FDMS) at http://www.Regulations.gov ; or to Arita... the Office of Management and Budget (OMB) for each collection of information they conduct or...

  10. 76 FR 37815 - Cooperative Agreement To Support Shellfish Safety Assistance Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-28

    ... HUMAN SERVICES Food and Drug Administration Cooperative Agreement To Support Shellfish Safety Assistance Project AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA), Center for Food Safety and Applied Nutrition (CFSAN), Office of Food Safety is...

  11. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shellfish in Shanghai

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio parahaemolyticus is a marine and estuarine bacterium that poses a large threat to human health worldwide. It has been the leading bacterial cause of seafood-borne illness. This study investigated the prevalence and drug resistance of V. parahaemolyticus isolated from retail shellfish in Shang...

  12. Complete genome sequence of the larval shellfish pathogen Vibrio Tubiashii type strain ATCC 19109

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vibrio tubiashii is a larval shellfish pathogen. Here we report the first closed genome sequence for this species (American Type Culture Collection type strain 19109), which has two chromosomes (3,294,490 and 1,766,582 bp), two megaplasmids (251,408 and 122,808 bp) and two plasmids (57,076 and 47,9...

  13. [Determination of azaspiracid-1 in shellfishes by liquid chromatography with tandem mass spectrometry].

    PubMed

    Yao, Jianhua; Tan, Zhijun; Zhou, Deqing; Guo, Mengmeng; Xing, Lihong; Yang, Shouguo

    2010-04-01

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of azaspiracid-1 (AZA1) in shellfishes was described. After being extracted using methanol and water (80:20, v/v), the extract was cleaned-up by solid phase extraction (SPE) of MAX column, then determined by using a reversed-phase high performance liquid chromatography (HPLC) isocratic program coupled with tandem mass spectrometry in selected reaction monitoring mode (SRM). And the extract was eluted with acetonitrile-water (80:20, v/v) on an Atlantis dC18 column (150 mm x 4.6 mm, 5.0 microm) with mobile phase containing 50 mmol/L formic acid and 2 mmol/L ammonium formate. The detection limit was 11.00 pg/g. The calibration curve was linear (R2 = 0.998 1) in the range of 48.85-2 442 ng/L. The average recoveries of the shellfish tissue extract at three spiked levels (36.64, 73.27, 146.54 pg/g) were from 75.8% to 82.5% (n = 6). The relative standard derivations (RSDs) were less than 10%. The 112 shellfish samples from the local markets of Dalian, Qingdao, Guangzhou were detected by the method, and AZA1 was detected in some samples from Dalian and Guangzhou. The results showed that the method is simple, rapid, sensitive and suitable for the detection of AZA1 in shellfishes. PMID:20712117

  14. TOXICITY ASSESSMENT OF PARALYTIC SHELLFISH POISONS (PSPS) USING QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIPS

    EPA Science Inventory

    The most significant harmful algal bloom (HAB) toxin in terms of public health is commonly known as paralytic shellfish poisons (PSPs, "red tides" toxins). PSPs are neurotoxins produced by marine dinoflagellates and some cyanobacteria. PSPs comprise of over 21 natural toxins wi...

  15. MODELING FISH AND SHELLFISH DISTRIBUTIONS IN THE MOBILE BAY ESTUARY, USA

    EPA Science Inventory

    Estuaries in the Gulf of Mexico provide rich habitat for many fish and shellfish, including those that have been identified as economically and ecologically important. For the Mobile Bay estuary, we developed statistical models to relate distributions of individual species and sp...

  16. Spatial and temporal heterogeneity of bacteria across an intertidal shellfish bed: implications for regulatory monitoring of faecal indicator organisms.

    PubMed

    Clements, Katie; Quilliam, Richard S; Jones, David L; Wilson, James; Malham, Shelagh K

    2015-02-15

    Routine bacterial monitoring of shellfish beds using indicator species is a common global practice designed to prevent human consumption of contaminated shellfish products. However, current bacteriological monitoring procedures which focus on the quantification of faecal indicator organisms (FIOs) as a proxy for microbial pollution may not be representative of total bacterial contamination levels present in shellfish harvesting areas. The objective of this study was to critically assess the accuracy of current monitoring strategies by quantifying the spatial (lateral and longitudinal distance) and temporal (seasonality and tidal state) concentrations of FIOs (Escherichia coli and total coliforms) within a single intertidal commercially harvested shellfish bed. Spatial and temporal FIO dynamics, including the effects of tidal state and seasonality, were quantified in mussel flesh and sediment samples from a single intertidal mussel (Mytilus edulis) bed. Our results confirmed that FIO concentrations across a shellfish bed were heterogeneous over larger spatial and temporal scales, but showed no relation to the concentrations of autochthonous bacteria, such as Vibrio spp., or the physico-chemical parameters of the sediment. These results have important implications for both public health and the economic prosperity of the shellfish industry, and demonstrate the importance of accommodating both spatial and temporal fluctuations in routine bacteriological monitoring protocols. We conclude that current FIO monitoring procedures may not accurately represent levels of microbial contamination within shellfish harvesting areas and that more robust microbiological testing procedures need developing. PMID:25460933

  17. Occurrence and Antibiotic Resistance of Vibrio parahaemolyticus from Shellfish in Selangor, Malaysia

    PubMed Central

    Letchumanan, Vengadesh; Pusparajah, Priyia; Tan, Loh Teng-Hern; Yin, Wai-Fong; Lee, Learn-Han; Chan, Kok-Gan

    2015-01-01

    High consumer demand for shellfish has led to the need for large-scale, reliable shellfish supply through aquaculture or shellfish farming. However, bacterial infections which can spread rapidly among shellfish poses a major threat to this industry. Shellfish farmers therefore often resort to extensive use of antibiotics, both prophylactically and therapeutically, in order to protect their stocks. The extensive use of antibiotics in aquaculture has been postulated to represent a major contributing factor in the rising incidence of antimicrobial resistant pathogenic bacteria in shellfish. This study aimed to investigate the incidence of pathogenic Vibrio parahaemolyticus and determine the antibiotic resistance profile as well as to perform plasmid curing in order to determine the antibiotic resistance mediation. Based on colony morphology, all 450 samples tested were positive for Vibrio sp; however, tox-R assay showed that only 44.4% (200/450) of these were V. parahaemolyticus. Out of these 200 samples, 6.5% (13/200) were trh-positive while none were tdh-positive. Antibiotic resistance was determined for all V. parahaemolyticus identified against 14 commonly used antibiotics and the multiple antibiotic resistance index (MAR) was calculated. The isolates demonstrated high resistance to several antibiotics tested- including second and third-line antibiotics- with 88% resistant to ampicillin, 81% to amikacin,70.5% to kanamycin, 73% to cefotaxime, and 51.5% to ceftazidime. The MAR index ranged from 0.00 to 0.79 with the majority of samples having an index of 0.36 (resistant to five antibiotics). Among the 13 trh-positive strains, almost 70% (9/13) demonstrated resistance to 4 or more antibiotics. Plasmid profiling for all V. parahaemolyticus isolates revealed that 86.5% (173/200) contained plasmids - ranging from 1 to 7 plasmids with DNA band sizes ranging from 1.2 kb to greater than 10 kb. 6/13 of the pathogenic V. pathogenic strains contained plasmid. After plasmid

  18. The potential for marine bivalve shellfish to act as transmission vehicles for outbreaks of protozoan infections in humans: a review.

    PubMed

    Robertson, L J

    2007-12-15

    Most marine molluscan bivalve shellfish feed on suspended phytoplankton which are trapped from water pumped across the gills by ciliary action. Pathogenic microorganisms in the water may be filtered by the gills during feeding, and become concentrated in the digestive glands/tract. If these pathogens are not excreted or inactivated by the shellfish, or in subsequent preparatory processes, they may be ingested by consumers, the shellfish thereby acting as vehicles of infection. The protozoan parasites Cryptosporidium spp., Giardia duodenalis and Toxoplasma gondii have the potential to be transmitted in this way, and here we review the accumulating knowledge on the occurrence and survival of the transmission stages of these parasites in shellfish, whilst also emphasising the considerable gaps in our knowledge. Relevant information is particularly lacking for T. gondii, which, in comparison with Cryptosporidium spp. and G. duodenalis, has been relatively under-researched in this context. Although it seems evident that these shellfish can accumulate and concentrate all three of these parasites from the surrounding water, whether Giardia cysts remain viable and infectious is unknown, and some evidence suggests that they may be inactivated by the shellfish. Although both Toxoplasma and Cryptosporidium apparently retain their infectivity for prolonged periods in shellfish, the actual public health threat posed by these parasites via these shellfish is unclear, largely because there is minimal evidence of infection transmission. Reasons for this apparent lack of infection transmission are discussed and it is recommended that the potential for transmission via shellfish consumption is recognised by those concerned with investigating transmission of these infections. PMID:17928081

  19. Chlorinated and brominated organic pollutants in shellfish from the Yellow Sea and East China Sea.

    PubMed

    Yin, Ge; Asplund, Lillemor; Qiu, Yanling; Zhou, Yihui; Wang, Hua; Yao, Zongli; Jiang, Jianbin; Bergman, Åke

    2015-02-01

    The global contamination with persistent organic pollutants (POPs), or compounds with similar characteristics, is well known. Still there are data gaps for POP concentrations from many areas in the world. The aim of the present study is to assess several legacies POPs and also hexabromocyclododecane (HBCDD) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in shellfish from three locations in the Yellow Sea and East China Sea. The sources of the contaminants are discussed. Pooled samples were treated by liquid-liquid extraction and acid and column cleanup prior to analysis by gas chromatogram equipped with electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). The by far most abundant environmental contaminant originates from dichlorodiphenyltrichloroethane (DDT), independent of species analyzed or sampling site. The results indicate ongoing or at least recent discharges of DDT. The second highest concentrations were reported for HBCDD (21-40 ng/g fat) in the shellfish, independent of sampling sites. The two natural products, 6-MeO-BDE-47 and 2'-MeO-BDE-68, were also present in the shellfish (1.3-22 and 1-14 ng/g fat, respectively). The polychlorinated biphenyl (PCB) congener CB-153 (0.8-6.5 ng/g fat), hexachlorobenzene (HCB) (1.1-3.6 ng/g fat), and β-hexachlorocyclohexane (β-HCH) (2.3-4.9 ng/g fat) were all higher than the concentrations of other HCH isomers, β-endosulfan, PBDE congeners, and mirex. Apart from the DDTs and HBCDDs, it is evident that the pollution of shellfish was similar to, or lower than, the contamination of shellfish in other parts of the world. PMID:24958534

  20. Bio-filler from waste shellfish shell: preparation, characterization, and its effect on the mechanical properties on polypropylene composites.

    PubMed

    Li, Hai-Yan; Tan, Ye-Qiang; Zhang, Lu; Zhang, Yun-Xiang; Song, Yi-Hu; Ye, Ying; Xia, Mei-Sheng

    2012-05-30

    Waste shellfish shell stacking with a significant odor and toxicity which are hazardous to human constitutes a serious environmental hazard. For utilization of waste shellfish shell resource, granule of shellfish shell (SS) was prepared from waste shellfish shell by removing cuticle, crushing, grinding and shearing emulsification and was introduced as a filler to reinforce polypropylene (PP). The mechanical behavior of PP/SS composite shows a higher yield strain, yield strength, tensile strength and elongation at break than traditional commercial calcium carbonate (CC) filled PP. Yield strength of PP/SS composite with 2% SS is improved by 11.1% due to the formation of β-crystalline PP phase. Using waste SS for producing bio-filler for filling PP is an effective and prospective measure to deal with waste SS, which is valuable for industrial production and practical application as fillers for reinforcing polymers. PMID:22476096

  1. RELATIONS OF FISH AND SHELLFISH DISTRIBUTIONS TO HABITAT AND WATER QUALITY IN THE MOBILE BAY ESTUARY, USA

    EPA Science Inventory

    The Mobile Bay estuary provides rich habitat for many fish and shellfish, including those identified as economically and ecologically important. The National Estuary Program has focused on restoration of degraded estuarine habitat on which these species depend. To support this ...

  2. Risk assessment of the amnesic shellfish poison, domoic acid, on animals and humans.

    PubMed

    Kumar, K Prem; Kumar, Sreeletha Prem; Nair, G Achuthan

    2009-05-01

    Risk assessment of the amnesic shellfish poison, domoic acid, a potent neurotoxin, is evaluated based on its current knowledge and its harmful effects, and is presented under four headings, viz., (1) hazard identification, (2) dose response assessment, (3) exposure assessment and (4) risk characterization. Domoic acid binds the glutamate receptor site of the central nervous system (CNS) of humans and causes depolarization of neurons and an increase in cellularcalcium. In nature, domoic acid is produced by the algae, Pseudonitzschia spp. and they enter into the body of shellfish through their consumption. This toxin is reported to cause gastroenteritis, renal insufficiency confusion and memory loss in humans, since it affects the hippocampus of the brain. In rats, intraperitonial and oral administration of domoic acid result in scratching, tremor and convulsions, and in monkeys, the toxic symptoms like mastication, salivation, projectile vomiting, weakness, teeth grinding and lethargy are apparent. The no-observed-adverse-effect-level (NOAEL) in animals reveals that pure toxin is more effective than those isolated from shellfish. Based on LD50 values, it is found that intraperitonial administration of this toxin in animals is 31 fold more effective than oral administration. Low levels of domoic acid (0.20-0.75 ppm) show no toxic symptoms in non-human primates, but clinical effects are apparent in them and in humans, at a concentration of 1.0 ppm. The tolerable daily intake (TDI) of domoic acid for humans is calculated as 0.075 ppm, whereas for razor clams and crabs, the TDI are 19.4 and 31.5 ppm respectively. The hazard quotient (HQ) is found to be 2. Being an irreversible neurotoxin, domoic acid has severe public health implications. Death occurs in those above 68 years old. In order to ensure adequate protection to public health, the concentration of domoic acid in shellfish and shellfish parts at point of sale shall not exceed the current permissible limit of 20

  3. Occurrence and seasonal variations of algal toxins in water, phytoplankton and shellfish from North Stradbroke Island, Queensland, Australia.

    PubMed

    Takahashi, Eri; Yu, Qiming; Eaglesham, Geoff; Connell, Des W; McBroom, James; Costanzo, Simon; Shaw, Glen R

    2007-10-01

    A number of marine microalgae are known to produce toxins that can accumulate in shellfish and when eaten, lead to toxic and potentially fatal reactions in humans. This paper reports on the occurrence and seasonal variations of algal toxins in the waters, phytoplankton and shellfish of Southeast Queensland, Australia. These algal toxins include okadaic acid (OA), domoic acid (DA), gymnodimine (GD), pectenotoxin-2 (PTX-2) and pectenotoxin-2-seco acid (PTX-2-SA), which were detected in the sampled shellfish and phytoplankton, via HPLC-MS/MS. Dissolved OA, PTX-2 and GD were also detected in the samples collected from the water column. This was the first occasion that DA and GD have been reported in shellfish, phytoplankton and the water column in Queensland waters. Phytoplankton tows contained both the toxic Dinophysis and Pseudo-nitzschia algae species, and are suspected of being the most likely producers of the OA, PTX-2s and DA found in shellfish of this area. The number of cells, however, did not correlate with the amount of toxins present in either shellfish or phytoplankton. This indicates that toxin production by algae varies with time and the species present and that number of cells alone cannot be used as an indicator for the presence of toxins. The presence of OA and PTX-2s were more frequently seen in the summer, while DA and GD were detected throughout the year and without any obvious seasonal patterns. PMID:17512582

  4. Indirect human impacts turn off reciprocal feedbacks and decrease ecosystem resilience.

    PubMed

    Bertness, Mark D; Brisson, Caitlin P; Crotty, Sinead M

    2015-05-01

    Creek bank salt marsh die-off is a conservation problem in New England, driven by predator depletion, which releases herbivores from consumer control. Many marshes, however, have begun to recover from die-off. We examined the hypothesis that the loss of the foundation species Spartina alterniflora has decreased facilitator populations, weakening reciprocal positive plant/animal feedbacks, resilience, and slowing recovery. Field surveys and experiments revealed that loss of Spartina leads to decreased biodiversity, and increased mortality and decreased growth of the ribbed mussel Geukensia demissa, a key facilitator of Spartina. Experimental addition of Geukensia facilitators to creek banks accelerated Spartina recovery, showing that their loss limits recovery and the reciprocal feedbacks that drive community resilience. Reciprocal positive feedbacks involving foundation species, often lost to human impacts, may be a common, but generally overlooked mechanism of ecosystem resilience, making their reestablishment a valuable restoration tool. PMID:25432574

  5. Synthesis of the Paralytic Shellfish Poisons (+)-Gonyautoxin 2, (+)-Gonyautoxin 3, and (+)-11,11-Dihydroxysaxitoxin.

    PubMed

    Mulcahy, John V; Walker, James R; Merit, Jeffrey E; Whitehead, Alan; Du Bois, J

    2016-05-11

    The paralytic shellfish poisons are a collection of guanidine-containing natural products that are biosynthesized by prokaryote and eukaryote marine organisms. These compounds bind and inhibit isoforms of the mammalian voltage-gated Na(+) ion channel at concentrations ranging from 10(-11) to 10(-5) M. Here, we describe the de novo synthesis of three paralytic shellfish poisons, gonyautoxin 2, gonyautoxin 3, and 11,11-dihydroxysaxitoxin. Key steps include a diastereoselective Pictet-Spengler reaction and an intramolecular amination of an N-guanidyl pyrrole by a sulfonyl guanidine. The IC50's of GTX 2, GTX 3, and 11,11-dhSTX have been measured against rat NaV1.4, and are found to be 22 nM, 15 nM, and 2.2 μM, respectively. PMID:27138488

  6. Fatal paralytic shellfish poisoning in Kittlitz's Murrelet (Brachyramphus brevirostris) nestlings, Alaska, USA

    USGS Publications Warehouse

    Shearn-Bochsler, Valerie I.; Lance, Ellen W.; Corcoran, Robin; Piatt, John; Bodenstein, Barbara; Frame, Elizabeth; Lawonn, James

    2014-01-01

    Paralytic shellfish poisoning (PSP) is an acute toxic illness in humans resulting from ingestion of shellfish contaminated with a suite of neurotoxins (saxitoxins) produced by marine dinoflagellates, most commonly in the genus Alexandrium. Poisoning also has been sporadically suspected and, less often, documented in marine wildlife, often in association with an outbreak in humans. Kittlitz's Murrelet (Brachyramphus brevirostris) is a small, rare seabird of the Northern Pacific with a declining population. From 2008 to 2012, as part of a breeding ecology study, multiple Kittlitz's Murrelet nests on Kodiak Island, Alaska, were monitored by remote cameras. During the 2011 and 2012 breeding seasons, nestlings from several sites died during mild weather conditions. Remote camera observations revealed that the nestlings died shortly after consuming sand lance (Ammodytes hexapterus), a fish species known to biomagnify saxitoxin. High levels of saxitoxin were subsequently documented in crop content in 87% of nestling carcasses. Marine bird deaths from PSP may be underreported.

  7. A Putative Gene Cluster from a Lyngbya wollei Bloom that Encodes Paralytic Shellfish Toxin Biosynthesis

    PubMed Central

    Mihali, Troco K.; Carmichael, Wayne W.; Neilan, Brett A.

    2011-01-01

    Saxitoxin and its analogs cause the paralytic shellfish-poisoning syndrome, adversely affecting human health and coastal shellfish industries worldwide. Here we report the isolation, sequencing, annotation, and predicted pathway of the saxitoxin biosynthetic gene cluster in the cyanobacterium Lyngbya wollei. The gene cluster spans 36 kb and encodes enzymes for the biosynthesis and export of the toxins. The Lyngbya wollei saxitoxin gene cluster differs from previously identified saxitoxin clusters as it contains genes that are unique to this cluster, whereby the carbamoyltransferase is truncated and replaced by an acyltransferase, explaining the unique toxin profile presented by Lyngbya wollei. These findings will enable the creation of toxin probes, for water monitoring purposes, as well as proof-of-concept for the combinatorial biosynthesis of these natural occurring alkaloids for the production of novel, biologically active compounds. PMID:21347365

  8. A new simple screening method for the detection of paralytic shellfish poisoning toxins

    NASA Astrophysics Data System (ADS)

    Cheng, Jinping; Pi, Shuaishuai; Ye, Shufeng; Gao, Haomin; Yao, Lei; Jiang, Zhenyi; Song, Yuling; Xi, Lei

    2012-09-01

    The current testing for paralytic shellfish poisoning (PSP) in shellfish is based on the mouse bioassay (MBA). To alleviate animal welfare concerns, we evaluated the utility of using sublethal indicators of toxicity as an alternative to measuring time to death. Live mice were injected with a PSP congener and the changes in neurotransmitter levels were measured 60, 90, and 120 min after injection. Acetylcholine (ACh) was the most sensitive marker for PSP toxicity. The changes in neurotransmitter levels were most pronounced in the blood. Thus, measurement of Ach levels in the blood may serve as a sensitive predictor for PSP that would not require sacrifice of the mice. This method was relatively simple, sensitive (less than 1 μg/kg weight, equivalent to 20 ng/mL), low maintenance, and rapid (less than 60 min).

  9. PCR-based assessment of shellfish traceability and sustainability in international Mediterranean seafood markets.

    PubMed

    Galal-Khallaf, Asmaa; Ardura, Alba; Borrell, Yaisel J; Garcia-Vazquez, Eva

    2016-07-01

    Two mitochondrial markers (cytochrome oxidase COI and 16S rDNA) were employed for species identification of commercial shellfish from two Mediterranean countries. New COI Barcodes were generated for six species: Pleoticus robustus, Metapenaeopsis barbata, Parapenaeus fissuroides, Hymenopenaeus debilis, Metapenaeus affinis and Sepia aculeata. Biodiversity of the seafood species analyzed was greater in Egypt, with nine crustacean and two cephalopod species found compared with only three crustaceans and three cephalopods in Spain. In total, 17.2% and 15.2% products were mislabeled in Egypt and Spain, respectively. Population decline is a problem for some of the substitute species. Others were exotic and/or invasive in exporters' regions. This study offers the first comparable study of shellfish traceability in these Mediterranean markets. The PCR-based method used in this study proved to be reliable, effective and, therefore, could be employed for routine seafood analysis. PMID:26920298

  10. Biotransformations of Paralytic Shellfish Toxins by Bacteria Isolated from Bivalve Molluscs

    PubMed Central

    Smith, Elizabeth A.; Grant, Faye; Ferguson, Carolyn M. J.; Gallacher, Susan

    2001-01-01

    Due to the possibility that bacteria could be involved in the clearance of paralytic shellfish toxins (PST) from bivalve molluscs, investigations into which, if any, bacteria were able to grow at the expense of PST focused on several common shellfish species. These species were blue mussels, oysters, razor fish, cockles, and queen and king scallops. Bacteria associated with these shellfish were isolated on marine agar 2216 and characterized by their carbon utilization profiles (BIOLOG). Selected isolates from groups demonstrating 90% similarity were screened for their ability to metabolize a range of PST (gonyautoxins 1 and 4 [GTX 1/4], GTX 2/3, GTX 5, saxitoxin, and neosaxitoxin) using a novel screening method and confirming its results by high-performance liquid chromatography. Results suggest that molluscan bacteria have different capacities to utilize and transform PST analogues. For example, isolates M12 and R65 were able to reductively transform GTX 1/4 with concomitant production of GTX 2/3, while isolate Q5 apparently degraded GTX 1/4 without the appearance of other GTXs. Other observed possible mechanisms of PST transformations include decarbamoylation by isolate M12 and sulfation of GTXs by isolates Q5, R65, M12, and C3. These findings raise questions as to the possible role of bacteria resident in the shellfish food transport system. Some researchers have suggested that the microflora play a role in supplying nutritional requirements of the host. This study demonstrates that bacteria may also be involved in PST transformation and elimination in molluscan species. PMID:11319121

  11. Anti-Oxidative Activity of Mytiloxanthin, a Metabolite of Fucoxanthin in Shellfish and Tunicates

    PubMed Central

    Maoka, Takashi; Nishino, Azusa; Yasui, Hiroyuki; Yamano, Yumiko; Wada, Akimori

    2016-01-01

    Anti-oxidative activities of mytiloxanthin, a metabolite of fucoxanthin in shellfish and tunicates, were investigated. Mytiloxanthin showed almost the same activities for quenching singlet oxygen and the inhibition of lipid peroxidation as those of astaxanthin, which is a well-known singlet oxygen quencher. Furthermore, mytiloxanthin showed excellent scavenging activity for hydroxyl radicals and this activity was markedly higher than that of astaxanthin. PMID:27187417

  12. Anti-Oxidative Activity of Mytiloxanthin, a Metabolite of Fucoxanthin in Shellfish and Tunicates.

    PubMed

    Maoka, Takashi; Nishino, Azusa; Yasui, Hiroyuki; Yamano, Yumiko; Wada, Akimori

    2016-01-01

    Anti-oxidative activities of mytiloxanthin, a metabolite of fucoxanthin in shellfish and tunicates, were investigated. Mytiloxanthin showed almost the same activities for quenching singlet oxygen and the inhibition of lipid peroxidation as those of astaxanthin, which is a well-known singlet oxygen quencher. Furthermore, mytiloxanthin showed excellent scavenging activity for hydroxyl radicals and this activity was markedly higher than that of astaxanthin. PMID:27187417

  13. Heat treatment and the use of additives to improve the stability of paralytic shellfish poisoning toxins in shellfish tissue reference materials for internal quality control and proficiency testing.

    PubMed

    Burrell, Stephen; Clion, Valentin; Auroy, Virginie; Foley, Barry; Turner, Andrew D

    2015-06-01

    The need for homogenous reference materials stable for paralytic shellfish toxins is vital for the monitoring and quality assurance of these potent neurotoxins in shellfish. Two stabilisation techniques were investigated, heat treatment through autoclaving and the addition of preserving additives into the tissue matrix. Short and long-term stability experiments as well as homogeneity determination were conducted on materials prepared by both techniques in comparison with an untreated control using two LC-FLD methods. Both techniques improved the stability of the matrix and the PSP toxins present compared to the controls. A material was prepared using the combined techniques of heat treatment followed by spiking with additives and data is presented from this optimised reference material as used over a two year period in the Irish national monitoring program and in a development exercise as part of a proficiency testing scheme operated by QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe) since 2011. The results were indicative of the long-term stability of the material as evidenced through consistent assigned values in the case of the proficiency testing scheme and a low relative standard deviation of 10.5% for total toxicity data generated over 24 months. PMID:25816999

  14. Detection of noroviruses in shellfish and semiprocessed fishery products from a Belgian seafood company.

    PubMed

    Li, Dan; Stals, Ambroos; Tang, Qing-Juan; Uyttendaele, Mieke

    2014-08-01

    Shellfish have been implicated in norovirus (NoV) infection outbreaks worldwide. This study presents data obtained from various batches of shellfish and fishery products from a Belgian seafood company over a 6-month period. For the intact shellfish (oysters, mussels, and clams), 21 of 65 samples from 12 of 34 batches were positive for NoVs; 9 samples contained quantitative NoV levels at 3,300 to 14,300 genomic copies per g. For the semiprocessed fishery products (scallops and common sole rolls with scallop fragments), 29 of 36 samples from all eight batches were positive for NoVs; 17 samples contained quantitative NoV levels at 200 to 1,800 copies per g. This convenience study demonstrated the performance and robustness of the reverse transcription quantitative PCR detection and interpretation method and the added value of NoV testing in the framework of periodic control of seafood products bought internationally and distributed by a Belgian seafood processing company to Belgian food markets. PMID:25198595

  15. Implementing scientifically-robust and humane shellfish toxicity testing: we're still waiting.

    PubMed

    Buckland, Gemma

    2010-10-01

    The response to a Parliamentary Question put to the then-Home Office Minister on 8 March 2006, was that "All protocols for the detection of toxins in shellfish intended for human consumption were assigned a substantial severity limit", and that "A total of 6,468 animals were used in the relevant procedures [for the testing of shellfish toxins in the UK] during 2004". The official European Union (EU) method for shellfish toxin testing is the Mouse Bioassay (MBA). The MBA is the primary method, although the Rat Bioassay (RBA) is permitted for some toxins. Six years later, following the completion of ten reports from the European Food Safety Authority (EFSA) stating that current reliance on the MBA is scientifically inappropriate, the regulatory climate for testing is almost unchanged, despite the availability of alternatives. The reliance on such a scientifically questionable method, and the welfare concerns for the animals used, highlight the extent of the clash between policy and science. The ongoing struggle to persuade the European Commission to formally adopt non-animal testing methods for all of the relevant toxins has been fruitless, and evidence remains that thousands of mice are used every year in lethal tests that could be replaced. There is an absolute requirement for advanced scientific methods to replace questionable methods which rely on outdated, inaccurate animal tests; in this case, marine biotoxin testing has surely been waiting in line for far too long. PMID:21105757

  16. Fish and shellfish allergy in children: review of a persistent food allergy.

    PubMed

    Tsabouri, Sophia; Triga, Maria; Makris, Michael; Kalogeromitros, Dimitris; Church, Martin K; Priftis, Kostas N

    2012-11-01

    The increased consumption of fish and shellfish has resulted in more frequent reports of adverse reactions to seafood, emphasizing the need for more specific diagnosis and treatment of this condition and exploring reasons for the persistence of this allergy. This review discusses interesting and new findings in the area of fish and shellfish allergy. New allergens and important potential cross-reacting allergens have been identified within the fish family and between shellfish, arachnids, and insects. The diagnostic approach may require prick to-prick tests using crude extracts of both raw and cooked forms of seafood for screening seafood sensitization before a food challenge or where food challenge is not feasible. Allergen-specific immunotherapy can be important; mutated less allergenic seafood proteins have been developed for this purpose. The persistence of allergy because of seafood proteins' resistance after rigorous treatment like cooking and extreme pH is well documented. Additionally, IgE antibodies from individuals with persistent allergy may be directed against different epitopes than those in patients with transient allergy. For a topic as important as this one, new areas of technological developments will likely have a significant impact, to provide more accurate methods of diagnosing useful information to patients about the likely course of their seafood allergy over the course of their childhood and beyond. PMID:22554093

  17. New insights into the causes of human illness due to consumption of azaspiracid contaminated shellfish.

    PubMed

    Chevallier, O P; Graham, S F; Alonso, E; Duffy, C; Silke, J; Campbell, K; Botana, L M; Elliott, C T

    2015-01-01

    Azaspiracid (AZA) poisoning was unknown until 1995 when shellfish harvested in Ireland caused illness manifesting by vomiting and diarrhoea. Further in vivo/vitro studies showed neurotoxicity linked with AZA exposure. However, the biological target of the toxin which will help explain such potent neurological activity is still unknown. A region of Irish coastline was selected and shellfish were sampled and tested for AZA using mass spectrometry. An outbreak was identified in 2010 and samples collected before and after the contamination episode were compared for their metabolite profile using high resolution mass spectrometry. Twenty eight ions were identified at higher concentration in the contaminated samples. Stringent bioinformatic analysis revealed putative identifications for seven compounds including, glutarylcarnitine, a glutaric acid metabolite. Glutaric acid, the parent compound linked with human neurological manifestations was subjected to toxicological investigations but was found to have no specific effect on the sodium channel (as was the case with AZA). However in combination, glutaric acid (1 mM) and azaspiracid (50 nM) inhibited the activity of the sodium channel by over 50%. Glutaric acid was subsequently detected in all shellfish employed in the study. For the first time a viable mechanism for how AZA manifests itself as a toxin is presented. PMID:25928256

  18. New insights into the causes of human illness due to consumption of azaspiracid contaminated shellfish

    PubMed Central

    Chevallier, O. P.; Graham, S. F.; Alonso, E.; Duffy, C.; Silke, J.; Campbell, K.; Botana, L. M.; Elliott, C. T.

    2015-01-01

    Azaspiracid (AZA) poisoning was unknown until 1995 when shellfish harvested in Ireland caused illness manifesting by vomiting and diarrhoea. Further in vivo/vitro studies showed neurotoxicity linked with AZA exposure. However, the biological target of the toxin which will help explain such potent neurological activity is still unknown. A region of Irish coastline was selected and shellfish were sampled and tested for AZA using mass spectrometry. An outbreak was identified in 2010 and samples collected before and after the contamination episode were compared for their metabolite profile using high resolution mass spectrometry. Twenty eight ions were identified at higher concentration in the contaminated samples. Stringent bioinformatic analysis revealed putative identifications for seven compounds including, glutarylcarnitine, a glutaric acid metabolite. Glutaric acid, the parent compound linked with human neurological manifestations was subjected to toxicological investigations but was found to have no specific effect on the sodium channel (as was the case with AZA). However in combination, glutaric acid (1mM) and azaspiracid (50nM) inhibited the activity of the sodium channel by over 50%. Glutaric acid was subsequently detected in all shellfish employed in the study. For the first time a viable mechanism for how AZA manifests itself as a toxin is presented. PMID:25928256

  19. Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 1: Calibration Solutions.

    PubMed

    Beach, Daniel G; Crain, Sheila; Lewis, Nancy; LeBlanc, Patricia; Hardstaff, William R; Perez, Ruth A; Giddings, Sabrina D; Martinez-Farina, Camilo F; Stefanova, Roumiana; Burton, Ian W; Kilcoyne, Jane; Melanson, Jeremy E; Quilliam, Michael A; McCarron, Pearse

    2016-09-01

    Okadaic acid (OA) and its analogs dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic polyethers produced by marine dinoflagellates. These toxins accumulate in shellfish and cause diarrhetic shellfish poisoning (DSP) in humans. Regulatory testing of shellfish is essential to safeguard public health and for international trade. Certified reference materials (CRMs) play a key role in analytical monitoring programs. This paper presents an overview of the interdisciplinary work that went into the planning, production, and certification of calibration-solution CRMs for OA, DTX1, and DTX2. OA and DTX1 were isolated from large-scale algal cultures and DTX2 from naturally contaminated mussels. Toxins were isolated by a combination of extraction and chromatographic steps with processes adapted to suit the source and concentration of each toxin. New 19-epi-DSP toxin analogs were identified as minor impurities. Once OA, DTX1, and DTX2 were established to be of suitable purity, solutions were prepared and dispensed into flame-sealed glass ampoules. Certification measurements were carried out using quantitative NMR spectroscopy and LC-tandem MS. Traceability of measurements was established through certified external standards of established purity. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization, with components from the measurement, stability, and homogeneity studies being propagated into final combined uncertainties. PMID:27524810

  20. Determination of domoic acid in shellfish extracted by molecularly imprinted polymers.

    PubMed

    Lin, Zhengzhong; Wang, Dan; Peng, Aihong; Huang, Zhiyong; Lin, Yuhui

    2016-08-01

    A selective sample cleanup method using molecularly imprinted polymers was developed for the separation of domoic acid (a shellfish toxin) from shellfish samples. The molecularly imprinted polymers for domoic acid was prepared by emulsion polymerization using 1,3,5-pentanetricarboxylic acid as the template molecule, 4-vinyl pyridine as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, and Span80/Tween-80 (1:1 v/v) as the composite emulsifiers. The molecularly imprinted polymer showed high affinity to domoic acid with a dissociation constant of 13.5 μg/mL and apparent maximum adsorption capacity of 1249 μg/g. They were used as a selective sorbent for the detection of domoic acid from seafood samples coupled with high-performance liquid chromatography. The detection limit of 0.17 μg/g was lower than the maximum level permitted by several authorities. The mean recoveries of domoic acid from clam samples were 93.0-98.7%. It was demonstrated that the proposed method could be applied to the determination of domoic acid from shellfish samples. PMID:27311699

  1. Assessment of sodium channel mutations in Makah Tribal members of the U.S. Pacific Northwest as a potential mechanism of resistance to paralytic shellfish poisoning

    PubMed Central

    Adams, Nicolaus G.; Robertson, Alison; Grattan, Lynn M.; Pendleton, Steve; Roberts, Sparkle; Tracy, J. Kathleen; Trainer, Vera L.

    2015-01-01

    The Makah Tribe of Neah Bay, Washington, has historically relied on the subsistence harvest of coastal seafood, including shellfish, which remains an important cultural and ceremonial resource. Tribal legend describes visitors from other tribes that died from eating shellfish collected on Makah lands. These deaths were believed to be caused by paralytic shellfish poisoning, a human illness caused by ingestion of shellfish contaminated with saxitoxins, which are produced by toxin-producing marine dinoflagellates on which the shellfish feed. These paralytic shellfish toxins include saxitoxin, a potent Na+ channel antagonist that binds to the pore region of voltage gated Na+ channels. Amino acid mutations in the Na+ channel pore have been demonstrated to confer resistance to saxitoxin in softshell clam populations exposed to paralytic shellfish toxins present in their environment. Because of the notion of resistance to paralytic shellfish toxins, we aimed to determine if a resistance strategy was possible in humans with historical exposure to toxins in shellfish. We collected, extracted and purified DNA from buccal swabs of 83 volunteer Makah tribal members and sequenced the skeletal muscle Na+ channel (Nav1.4) at nine loci to characterize potential mutations in the relevant saxitoxin binding regions. No mutations of these specific regions were identified after comparison to a reference sequence. This study suggests that any resistance of Makah Tribal members to saxitoxin is not a function of Nav1.4 modification but may be due to mutations in neuronal or cardiac sodium channels or some other mechanism unrelated to sodium channel function.

  2. On the Frontline: Tracking Ocean Acidification in an Alaskan Shellfish Hatchery.

    PubMed

    Evans, Wiley; Mathis, Jeremy T; Ramsay, Jacqueline; Hetrick, Jeff

    2015-01-01

    The invasion of anthropogenic carbon dioxide (CO2) into the ocean is shifting the marine carbonate system such that saturation states of calcium carbonate (CaCO3) minerals are decreasing, and this is having a detrimental impact on early life stages of select shellfish species. The global, secular decrease in CaCO3 saturation states is occurring on top of a backdrop of large natural variability in coastal settings; progressively shifting the envelope of variability and leading to longer and more frequent exposure to adverse conditions. This is a great concern in the State of Alaska, a high-latitude setting vulnerable to rapid changes in the marine carbonate system, where an emerging shellfish industry plans major growth over the coming decades. Currently, the Alutiiq Pride Shellfish Hatchery (APSH) in Seward, Alaska is the only hatchery in the state, and produces many shellfish species with early life stages known to be sensitive to low CaCO3 saturation states. Here we present the first land-based OA measurements made in an Alaskan shellfish hatchery, and detail the trends in the saturation state of aragonite (Ωarag), the more soluble form of CaCO3, over a 10-month period in the APSH seawater supply. These data indicate the largest changes are on the seasonal time scale, with extended periods of sub-optimal Ωarag levels (Ωarag < 1.5) in winter and autumn associated with elevated water column respiration and short-lived runoff events, respectively. The data pinpoint a 5-month window of reprieve with favorable Ωarag conditions above the sub-optimal Ωarag threshold, which under predicted upper-bound CO2 emissions trajectories is estimated to close by 2040. To date, many species in production at APSH remain untested in their response to OA, and the data presented here establish the current conditions at APSH as well as provide a framework for hatchery-based measurements in Alaska. The current and expected conditions seen at APSH are essential to consider for this

  3. On the Frontline: Tracking Ocean Acidification in an Alaskan Shellfish Hatchery

    PubMed Central

    Evans, Wiley; Mathis, Jeremy T.; Ramsay, Jacqueline; Hetrick, Jeff

    2015-01-01

    The invasion of anthropogenic carbon dioxide (CO2) into the ocean is shifting the marine carbonate system such that saturation states of calcium carbonate (CaCO3) minerals are decreasing, and this is having a detrimental impact on early life stages of select shellfish species. The global, secular decrease in CaCO3 saturation states is occurring on top of a backdrop of large natural variability in coastal settings; progressively shifting the envelope of variability and leading to longer and more frequent exposure to adverse conditions. This is a great concern in the State of Alaska, a high-latitude setting vulnerable to rapid changes in the marine carbonate system, where an emerging shellfish industry plans major growth over the coming decades. Currently, the Alutiiq Pride Shellfish Hatchery (APSH) in Seward, Alaska is the only hatchery in the state, and produces many shellfish species with early life stages known to be sensitive to low CaCO3 saturation states. Here we present the first land-based OA measurements made in an Alaskan shellfish hatchery, and detail the trends in the saturation state of aragonite (Ωarag), the more soluble form of CaCO3, over a 10-month period in the APSH seawater supply. These data indicate the largest changes are on the seasonal time scale, with extended periods of sub-optimal Ωarag levels (Ωarag < 1.5) in winter and autumn associated with elevated water column respiration and short-lived runoff events, respectively. The data pinpoint a 5-month window of reprieve with favorable Ωarag conditions above the sub-optimal Ωarag threshold, which under predicted upper-bound CO2 emissions trajectories is estimated to close by 2040. To date, many species in production at APSH remain untested in their response to OA, and the data presented here establish the current conditions at APSH as well as provide a framework for hatchery-based measurements in Alaska. The current and expected conditions seen at APSH are essential to consider for this

  4. Development and evaluation of a RT-LAMP assay for rapid detection of hepatitis E virus from shellfish.

    PubMed

    Gao, Shenyang; Li, Dandan; Liu, Ying; Zha, Enhui; Wang, Shen; Li, Yonggang; Zhou, Tiezhong; Yue, Xiqing

    2016-03-01

    Hepatitis E virus (HEV) has becoming a well known zoonotic enteric pathogen and circulated widely inter human-animal-water-food. Generally, detection of the virus has relied on conventional reverse transcription-PCR (RT-PCR) and TaqMan/SYBR quantitative real-time RT-PCR (RT-qPCR), but these tools are usually disadvantages in time-consuming and expensive instruments required. In the present study, we report here on the development of a one-step single-tube reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for rapid detection of HEV contamination in shellfish. The amplification is completed under the isothermal condition (63 °C) for 60 min, and can be visually evaluated by staining at a time in about 1h. In addition, a total of 315 shellfish (80 Anadara granosa, 115 Scapharca subcrenata and 120 Ruditapes philippinarum) collected monthly from the Jinzhou coastal estuary of China Bohai gulf were investigated for HEV contamination by the RT-LAMP compared with a standard RT-qPCR. It was found that genotype 4 HEV was detected in all three species of shellfish sampled using the RT-LAMP assay and was in accordance with RT-qPCR detection of HEV in shellfish. Summarily, our results indicate that the RT-LAMP is a rapid, specific, sensitive and reliable method. This method offers a new tool for the routine monitoring of HEV contamination in shellfish or its harvesting waters in field. PMID:26741532

  5. Application of the Pearl model to analyze fecal coliform data from conditionally approved shellfish harvest areas in seven Texas bays.

    PubMed

    Conte, F S; Ahmadi, A

    2014-09-01

    The U.S. National Shellfish Sanitation Program (NSSP) 14/43 standard states that conditionally approved shellfish growing areas must be closed for harvest when the geometric mean of fecal coliform concentration exceeds the NSSP limit of 14 most probable number (MPN)/100 mL, or the estimated 90th percentile of fecal coliform concentrations exceeds 43 MPN/100 mL for a five-tube test. The authors hypothesized that the NSSP 14/43 standard is not sufficient to protect the public from risks from consumption of biologically contaminated shellfish and the standard should be modified to 8/26 MPN/100 mL. To verify this hypothesis, the authors analyzed fecal coliform data from conditionally approved shellfish harvest areas of seven Texas bays using the Pearl sanitation model. Results showed that the shellfish closure rules mandated by the Texas Department of State Health Services actually enforced the "Pearl" limits of 8/26 MPN/100 mL, and not the NSSP limit of 14/43 MPN/100 mL. PMID:25226781

  6. A duplex quantitative real-time PCR assay for the detection of Haplosporidium and Perkinsus species in shellfish.

    PubMed

    Xie, Zhixun; Xie, Liji; Fan, Qing; Pang, Yaoshan; Deng, Xianwen; Xie, Zhi Qin; Liu, Jiabo; Khan, Mazhar I

    2013-04-01

    A duplex quantitative real-time polymerase chain reaction (dq-PCR) assay was optimized to simultaneously detect Haplosporidium spp. and Perkinsus spp. of shellfish in one reaction. Two sets of specific oligonucleotide primers for Haplosporidium spp. and Perkinsus spp., along with two hydrolysis probes specific for each parasite group, were used in the assay. The dq-PCR results were detected and analyzed using the Light Cycler 2.0 software system. The dq-PCR identified and differentiated the two protozoan parasite groups. The sensitivity of the dq-PCR assay was 200 template copies for both Haplosporidium spp. and Perkinsus spp. No DNA product was amplified when known DNA from Marteilia refringens, Toxoplasma gondii, Bonamia ostreae, Escherichia coli, Cymndinium spp., Mykrocytos mackini, Vibrio parahaemolyticus, and shellfish tissue were used as templates. A total of 840 oyster samples from commercial cultivated shellfish farms from two coastal areas in China were randomly collected and tested by dq-PCR. The detection rate of Haplosporidium spp. was 8.6% in the Qindao, Shandong coastal area, whereas Perkinsus spp. was 8.3% coastal oysters cultivated from shellfish farms of Beihai, Guangxi. The dqPCR results suggested that Haplosporidium spp. was prevalent in oysters from Qindao, Shandong, while Perkinsus spp. was prevalent in oysters from the coastal areas of Beihai, Guangxi. This dq-PCR could be used as a diagnostic tool to detect Haplosporidium spp. and Perkinsus spp. in cultivated shellfish. PMID:23371501

  7. Chemical risks associated with consumption of shellfish harvested on the north shore of the St. Lawrence River's lower estuary.

    PubMed Central

    Gagnon, Fabien; Tremblay, Thierry; Rouette, Justine; Cartier, Jacques-François

    2004-01-01

    Shellfish have the capacity to accumulate chemical contaminants found in their biotope and therefore present a potential risk for consumers. This study was conducted to assess the chemical risks associated with consumption of shellfish harvested on the north shore of the St. Lawrence River's lower estuary. A survey was carried out on 162 recreational harvesters, and shellfish were sampled for chemical contaminant analysis. We quantified 10 metals, 22 polycyclic aromatic hydrocarbons (PAHs), 14 polychlorinated biphenyls (PCBs), and 10 chlorinated pesticides. We subsequently evaluated cancer and noncancer risks for four consumption scenarios based on our survey results and published results. Soft-shell clams (Mya arenaria) were by far the most consumed shellfish species. Of the 56 selected contaminants, 36 were detected in the 23 homogenates of soft-shell clam meat. None of the contaminants found in the soft-shell clams were associated with intakes that exceed the main exposure limit recommendations proposed to prevent noncancer effects. However, several limits must be considered before drawing conclusions about the relative safety of shellfish consumption regarding this end point. Furthermore, inorganic arsenic and PCBs were present in sufficient concentrations to lead to cancer risks exceeding the level often considered acceptable for environmental exposure (1 x 10 (-4) to 1 x 10(-6)) in each of the four scenarios, even for the lowest observed scenario of 15 meals of soft-shell clams per year. PMID:15175177

  8. Uptake, transfer and elimination kinetics of paralytic shellfish toxins in common octopus (Octopus vulgaris).

    PubMed

    Lopes, Vanessa M; Baptista, Miguel; Repolho, Tiago; Rosa, Rui; Costa, Pedro Reis

    2014-01-01

    Marine phycotoxins derived from harmful algal blooms are known to be associated with mass mortalities in the higher trophic levels of marine food webs. Bivalve mollusks and planktivorous fish are the most studied vectors of marine phycotoxins. However, field surveys recently showed that cephalopod mollusks also constitute potential vectors of toxins. Thus, here we determine, for the first time, the time course of accumulation and depuration of paralytic shellfish toxins (PSTs) in the common octopus (Octopus vulgaris). Concomitantly, the underlying kinetics of toxin transfer between tissue compartments was also calculated. Naturally contaminated clams were used to orally expose the octopus to PSTs during 6 days. Afterwards, octopus specimens were fed with non-contaminated shellfish during 10 days of depuration period. Toxins reached the highest concentrations in the digestive gland surpassing the levels in the kidney by three orders of magnitude. PSTs were not detected in any other tissue analyzed. Net accumulation efficiencies of 42% for GTX5, 36% for dcSTX and 23% for C1+2 were calculated for the digestive gland. These compounds were the most abundant toxins in both digestive gland and the contaminated shellfish diet. The small differences in relative abundance of each toxin observed between the prey and the cephalopod predator indicates low conversion rates of these toxins. The depuration period was better described using an exponential decay model comprising a single compartment - the entire viscera. It is worth noting that since octopuses' excretion and depuration rates are low, the digestive gland is able to accumulate very high toxin concentrations for long periods of time. Therefore, the present study clearly shows that O. vulgaris is a high-potential vector of PSTs during and even after the occurrence of these toxic algal blooms. PMID:24316438

  9. Toxic equivalency factors for PAH and their applicability in shellfish pollution monitoring studies.

    PubMed

    Law, Robin J; Kelly, Carole; Baker, Kerry; Jones, Jacqueline; McIntosh, Alistair D; Moffat, Colin F

    2002-06-01

    Fish and shellfish are exposed to a wide range of polycyclic aromatic hydrocarbons (PAH) following oil spills at sea, and can become contaminated as a result. Finfish have a more effective mixed-function oxidase enzyme system than shellfish, and are therefore able to metabolise and excrete PAH more effectively than the invertebrates. Thus, contamination by high-molecular weight PAH, including those with carcinogenic potential and so of concern with regard to human consumers, is therefore usually observed in shellfish, and particularly in bivalve molluscs. Oil spills are not the sole source of PAH, however, as parent compounds are also generated by a wide range of combustion processes. In this paper, consideration is given to monitoring data gathered following recent oil spills (both of crude oil and diesel fuel), alongside data from other studies. These include studies conducted around a former gasworks site and downstream of an aluminium smelter in the UK, and from mussel monitoring studies undertaken in the UK and the USA (including the Exxon Valdez oil spill and the National Status and Trends programme), and in other countries in Europe. For comparative purposes the PAH concentrations are summed and also expressed as benzo[a]pyrene equivalents, their relative concentrations being weighted in relation to the carcinogenic potential of individual PAH compounds using toxic equivalency factors (TEF). Our aim was to assess the utility of this approach in fishery resource monitoring and control following oil spills. Certainly this approach seems useful from the data assessed in this study. and the relative ranking of the various studies seems to reflect the relative degree of concern for human consumers due to the differing contamination sources. As a simple tool for control purposes it is equally applicable to PAH derived from oil spills, and from industrial and combustion sources. PMID:12094932

  10. Paralytic shellfish toxins in the freshwater cyanobacterium Aphanizomenon flos-aquae, isolated from Montargil reservoir, Portugal.

    PubMed

    Pereira, P; Onodera, H; Andrinolo, D; Franca, S; Araújo, F; Lagos, N; Oshima, Y

    2000-12-01

    Montargil reservoir, located in a dry flat area in the centre of Portugal, was filled in 1958 to fulfil agricultural, electric and industrial requirements. In May 1996, an intensive bloom of phytoplankton was detected. The algal community was strongly dominated by cyanobacteria with predominance of Aphanizomenon flos-aquae from May to June and Microcystis aeruginosa from July to August. Extracts of samples collected during the bloom period showed high toxicity by mouse bioassay. During the M. aeruginosa predominance period, the toxicity was ascribed to the presence of hepatotoxins, but clear symptoms of paralytic shellfish poison were observed when A. flos-aquae was the dominant species. In order to confirm the production of neurotoxins a strain of A. flos-aquae was isolated and established in culture. In this manuscript, we show the morphological characteristics and confirm paralytic shellfish toxins production by the strain isolated and maintained in culture. Identification of the saxitoxin analogs was achieved using high performance liquid chromatography with postcolumn fluorescence derivatization (HPLC-FLD) and liquid chromatographic mass spectrometry technique (LC-MS). The toxins found in the culture extract were GTX5 (64.5 mol%), neoSTX (23.0 mol%), dcSTX (6.1 mol%), STX (5.4 mol%) and GTX6 (1.1 mol%). This is, to our knowledge, the first report of unambiguous evidence of paralytic shellfish toxins produced by freshwater cyanobacteria in Portugal. The toxin profile is rather different from the previously reported PSP producing A. flos-aquae and demonstrates its diversity in terms of toxin production. PMID:10858510

  11. The ecological role of bivalve shellfish aquaculture in the estuarine environment: A review with application to oyster and clam culture in West Coast (USA) estuaries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquaculture is viewed as a potential mechanism to meet the growing demand for seafood around the world. The future of bivalve shellfish aquaculture in the U.S. hinges on sustainable practices on the part of industry and a more consistent regulatory regime. Bivalve shellfish aquaculture is a recent...

  12. Bioaccumulation of mycotoxins by shellfish: contamination of mussels by metabolites of a Trichoderma koningii strain isolated in the marine environment.

    PubMed

    Sallenave, C; Pouchus, Y F; Bardouil, M; Lassus, P; Roquebert, M F; Verbist, J F

    1999-01-01

    To determine whether toxic metabolites produced by fungi could cause shellfish toxicities, mussels were contaminated in laboratory conditions by sterile filtrates of a liquid culture of a strain of the fungus Trichoderma koningii previously isolated from a shellfish, the cockle (Cerastoderma edule). Mussels were kept in aerated natural seawater and fed with a culture of the microalga Isochrysis galbana, to which a filtrate of liquid fungal culture was added. Mussels were exposed to contamination for 7 days at 16 or 20 degrees C and extractions were then performed and their activity tested on blowfly larvae. The same toxicity was found in the fungal filtrate and the shellfish, indicating bioaccumulation. The digestive gland was the most toxic part of the mussel, confirming contamination by filtration. Treated mussels produced a mucus which appeared to be a means of eliminating toxic metabolites. PMID:9920482

  13. [A case of food-dependent-exercise induced anaphylaxis possibly induced by shellfish (Sulculus Supertexta and Turbo Cornutus)].

    PubMed

    Juji, F; Takashima, H; Suko, M; Doi, M; Takaishi, T; Okudaira, H; Ito, K; Miyamoto, T

    1990-11-01

    A 17 years old girl experienced an anaphylactic reaction of urticaria, dyspnea, syncope and hypotension while riding a bicycle 55 minutes after eating shellfish Lapas shellfish which was a-like Sulculus Supertexta (SS). She recovered within several hours after the emergency treatment. Another attack occurred 3 months later while she was running with a dog 30 minutes after eating shellfish (Turbo Cornutus; TC). RAST scores were 4 for Lapas and 2 for TC. RAST inhibition test by ELISA showed a high crose-reaction between keyhole limpet hemocyanin (KLH) and Lapas, and between KLH and TC, while the cross reaction between Lapas and TC was low. Gel chromatography with sephacryl G-200 revealed that both Lapas and TC had several allergens with different molecules which were detected by ELISA. Exercise challenge produced an immediate fall of FEV1 and a significant increase in plasma histamine levels for 45 minutes. PMID:2288497

  14. Benthic response to shellfish farming in Thau lagoon: Pore water signature

    NASA Astrophysics Data System (ADS)

    Metzger, E.; Simonucci, C.; Viollier, E.; Sarazin, G.; Prévot, F.; Jézéquel, D.

    2007-04-01

    Vertical distributions of dissolved species across the sediment-water interface (SWI), including major cations (sodium, potassium, magnesium, calcium), minor cations (lithium, strontium, barium), redox sensitive species (dissolved manganese, iron, sulfate, sulfide, ammonium) and other chemical parameters (pH, alkalinity, soluble reactive phosphorous, dissolved silica) were studied in a Mediterranean lagoon used for intensive shellfish farming. In order to quantify the impact of this activity on diagenetic processes and the influence of seasonal changes, two stations contrasted with respect to organic carbon fluxes were sampled in Thau lagoon from March 2001 to August 2002 during four field campaigns in winter, spring, summer and fall. Well-defined layers enriched with redox sensitive species were observed following the conventional sequence of early diagenetic reactions. However, differences were observed between both stations in depths and thickness layers. Concentration gradients extended down to more than 92 cm depth at the central position of the lagoon (station C4 - 8 m depth) and down to 40 cm depth inside shellfish farming zones (station C5 - 9 m depth). Station C4 showed an unusual diagenetic signature: sharp dissolved oxygen, iron, nitrate and manganese gradients existed at the SWI but gradients of dissolved sulfide and alkalinity as well as other parameters (dissolved silica, Ba, etc.) were recorded only from 25 to 30 cm depth downward. Seasonal changes were observed in pore water composition as deep as 30-50 cm in station C4 (only 15 cm in station C5). The center of the lagoon is not directly subjected to biodeposits deriving from shellfish activity. Isotopic and bioturbation data allowed to rule out a reworking of the sediment deeper than a few centimeters. In addition to organic content of the sediment, physical parameters were likely to induce the 10-20 cm gap between dissolved iron and sulfide profile as well as the higher vertical extent of

  15. Sterol composition of shellfish species commonly consumed in the United States

    PubMed Central

    Phillips, Katherine M.; Ruggio, David M.; Exler, Jacob; Patterson, Kristine Y.

    2012-01-01

    Background Shellfish can be a component of a healthy diet due to a low fat and high protein content, but the cholesterol content of some species is often cited as a reason to limit their consumption. Data on levels of non-cholesterol sterols in commonly consumed species are lacking. Objective Shellfish were sampled and analyzed to update sterol data in the United States Department of Agriculture (USDA) National Nutrient Database for Standard Reference. Design Using a nationwide sampling plan, raw shrimp and sea scallops, canned clams, and steamed oysters, blue crab, and lobster were sampled from 12 statistically selected supermarkets across the United States in 2007–08. For each species, four composites were analyzed, each comprised of samples from three locations; shrimp and scallops from six single locations were also analyzed separately. Using validated analytical methodology, 14 sterols were determined in total lipid extracts after saponification and derivatization to trimethylsilyethers, using gas chromatography for quantitation and mass spectrometry for confirmation of components. Results Crab, lobster, and shrimp contained significant cholesterol (96.2–27 mg/100 g); scallops and clams had the lowest concentrations (23.4–30.1 mg/100 g). Variability in cholesterol among single-location samples of shrimp was low. The major sterols in the mollusks were brassicasterol (12.6–45.6 mg/100 g) and 24-methylenecholesterol (16.7–41.9 mg/100 g), with the highest concentrations in oysters. Total non-cholesterol sterols were 46.5–75.6 mg/100 g in five single-location scallops samples, but 107 mg/100 g in the sixth, with cholesterol also higher in that sample. Other prominent non-cholesterol sterols in mollusks were 22-dehydrocholesterol, isofucosterol, clionasterol, campesterol, and 24-norcholesta-5,22-diene-3β-ol (4–21 mg/100 g). Conclusions The presence of a wide range of sterols, including isomeric forms, in shellfish makes the analysis and quantitation

  16. Cluster analysis of toxins profile pattern as a tool for tracing shellfish contaminated with PSP-toxins.

    PubMed

    Wong, Chun-Kwan; Hung, Patricia; Ng, Henry C C; Lee, Siu-Yuen; Kam, Kai-Man

    2011-11-01

    Paralytic shellfish poisoning (PSP) is one of the most lethal biotoxin-induced diseases worldwide, which may pose serious public health threat and potential devastating economic damage on fisheries industry in the affected region(s). To prevent the importation of PSP contaminated shellfish to a community, detailed documentation on the supply chain and routine surveillance systems are, in principle, crucial measures to protect people from this intoxication. However, difficulties have always been encountered on the traceability of the source/origin of contaminated shellfish. In the present study, we reported the potential application of PSP-toxins profiles with similarity analysis that can be used to identify epidemiological linkage between shellfish samples collected from markets and patients during a PSP outbreak. PSP-toxins were identified and quantified by ion-pair chromatographic separation followed by post-column oxidation to fluorescent imino purine derivatives. Samples from a PSP incident and other surveillance samples collected in our past 7-year record were also compared for their similarity in PSP-toxins profiles patterns. Molar distributions (nmol%) of 10 PSP-toxins were analyzed by Unweighted Pair Group Method with Arithmetric averages (UPGMA). Three prominent clusters emerged with similarity levels reaching over 80% for each, suggesting that each group of samples probably originated from a same source/batch. The PSP-toxins profiles and toxicities determined from surveillance samples could provide premonitory clues on the occurrences of PSP incident and outbreak with corresponding toxin profiles in the later time. Due to species-specific characteristics of PSP-toxins composition and profile in shellfish under varieties of environmental and physiological conditions, PSP-toxins profile can be a specific and useful biochemical indicator for tracing PSP contaminated shellfish provided that spatio-temporal occurrence patterns of toxins profiles are available

  17. Onboard screening dockside testing as a new means of managing paralytic shellfish poisoning risks in federally closed waters

    NASA Astrophysics Data System (ADS)

    DeGrasse, Stacey; Conrad, Stephen; DiStefano, Paul; Vanegas, Camilo; Wallace, David; Jensen, Pete; Hickey, J. Michael; Cenci, Florence; Pitt, Jaclyn; Deardorff, Dave; Rubio, Fernando; Easy, Dorothy; Donovan, Mary Anne; Laycock, Maurice; Rouse, Debbie; Mullen, John

    2014-05-01

    Paralytic shellfish poisoning (PSP) is the foodborne intoxication associated with the consumption of seafood contaminated with naturally occurring neurotoxins known as paralytic shellfish toxins. To protect public health from this potentially fatal syndrome, harvesting closures are implemented when toxins exceed the regulatory action level. Traditional monitoring programs established by state shellfish authorities allow for timely closures in state waters with minimal negative impacts on industry. However, such monitoring programs are not feasible in federal offshore waters given their distance from shore and the range of their spatial coverage. Thus innovative management strategies were investigated for these offshore resources. Georges Bank, an offshore resource with an estimated market value of more than 3 billion in Atlantic surfclams and ocean quahogs, has been closed to harvesting following a temporary ban in 1989 and a subsequent indefinite closure in 1990 due to the risk of PSP. As a means of managing this risk and allowing harvest of safe shellfish from this important resource, the Onboard Screening Dockside Testing Protocol (referred to as the Protocol) was developed by the US Food and Drug Administration (FDA), National Marine Fisheries Service (NMFS), state shellfish control authorities, and industry. The Protocol, which sets forth control measures to ensure product safety and public health protection, was endorsed by the Interstate Shellfish Sanitation Conference (ISSC) for pilot testing. Briefly, the pilot study Protocol required that (1) the fishing vessel receive a permit from NMFS to harvest in closed waters, (2) a miniμm of five shellfish samples per intended harvest lot be tested for PSP toxins onboard, and (3) harvesting only occur when the samples tested from the intended fishing area are negative using the Jellett Rapid Tests or Abraxis Shipboard ELISA kits. Finally, product landed under the Protocol was confirmed to be safe for consumption

  18. Bioaccumulation Efficiency, Tissue Distribution, and Environmental Occurrence of Hepatitis E Virus in Bivalve Shellfish from France

    PubMed Central

    Grodzki, Marco; Schaeffer, Julien; Piquet, Jean-Côme; Le Saux, Jean-Claude; Chevé, Julien; Ollivier, Joanna; Le Pendu, Jacques

    2014-01-01

    Hepatitis E virus (HEV), an enteric pathogen of both humans and animals, is excreted by infected individuals and is therefore present in wastewaters and coastal waters. As bivalve molluscan shellfish are known to concentrate viral particles during the process of filter feeding, they may accumulate this virus. The bioaccumulation efficiencies of oysters (Crassostrea gigas), flat oysters (Ostrea edulis), mussels (Mytilus edulis), and clams (Ruditapes philippinarum) were compared at different time points during the year. Tissue distribution analysis showed that most of the viruses were concentrated in the digestive tissues of the four species. Mussels and clams were found to be more sensitive to sporadic contamination events, as demonstrated by rapid bioaccumulation in less than 1 h compared to species of oysters. For oysters, concentrations increased during the 24-h bioaccumulation period. Additionally, to evaluate environmental occurrence of HEV in shellfish, an environmental investigation was undertaken at sites potentially impacted by pigs, wild boars, and human waste. Of the 286 samples collected, none were contaminated with hepatitis E virus, despite evidence that this virus is circulating in some French areas. It is possible that the number of hepatitis E viral particles discharged into the environment is too low to detect or that the virus may have a very short period of persistence in pig manure and human waste. PMID:24795382

  19. Multi-Laboratory Study of Five Methods for the Determination of Brevetoxins in Shellfish Tissue Extracts

    PubMed Central

    Dickey, Robert W.; Plakas, Steven M.; Jester, Edward L.E.; El Said, Kathleen R.; Johannessen, Jan N.; Flewelling, Leanne J.; Scott, Paula; Hammond, Dan G.; Van Dolah, Frances M.; Leighfield, Tod A.; Bottein Dachraoui, Marie-Yasmine; Ramsdell, John S.; Pierce, Richard H.; Henry, Mike S.; Poli, Mark A.; Walker, Calvin; Kurtz, Jan; Naar, Jerome; Baden, Daniel G.; Musser, Steve M.; White, Kevin D.; Truman, Penelope; Miller, Aaron; Hawryluk, Timothy P.; Wekell, Marleen M.; Stirling, David; Quilliam, Michael A.; Lee, Jung K.

    2010-01-01

    A thirteen-laboratory comparative study tested the performance of four methods as alternatives to mouse bioassay for the determination of brevetoxins in shellfish. The methods were N2a neuroblastoma cell assay, two variations of the sodium channel receptor binding assay, competitive ELISA, and LC/MS. Three to five laboratories independently performed each method using centrally prepared spiked and naturally incurred test samples. Competitive ELISA and receptor binding (96-well format) compared most favorably with mouse bioassay. Between-laboratory relative standard deviations (RSDR) ranged from 10 to 20% for ELISA and 14 to 31% for receptor binding. Within-laboratory (RSDr) ranged from 6 to 15% for ELISA, and 5 to 31% for receptor binding. Cell assay was extremely sensitive but data variation rendered it unsuitable for statistical treatment. LC/MS performed as well as ELISA on spiked test samples but was inordinately affected by lack of toxin-metabolite standards, uniform instrumental parameters, or both, on incurred test samples. The ELISA and receptor binding assay are good alternatives to mouse bioassay for the determination of brevetoxins in shellfish. PMID:26436143

  20. Novel application of high pressure processing for the production of shellfish toxin matrix reference materials.

    PubMed

    Turner, Andrew D; Powell, Andy L; Burrell, Stephen

    2014-11-01

    The production of homogeneous and stable matrix reference materials for marine biotoxins is important for the validation and implementation of instrumental methods of analysis. High pressure processing was investigated to ascertain potential advantages this technique may have in stabilising paralytic shellfish poisoning toxins in shellfish tissues compared to untreated materials. Oyster tissues were subjected to a range of different temperatures and pressures, with results showing a significant reduction in biological activity in comparison to control samples, without significantly altering toxin profiles. Tissue subjected to pressures >600 MPa at 50 °C was assessed for homogeneity and stability. The sample homogeneity was determined using a pre-column oxidation LC-FLD method and shown to be within accepted levels of within batch repeatability. Short and long-term stability studies were conducted over a range of temperatures, with analysis by pre and post column oxidation LC-FLD demonstrating improved stability of toxins compared to the untreated materials and with epimerisation of toxins also notably reduced in treated materials. This study confirmed the technique of high pressure processing to improve the stability of PSP toxins compared to untreated wet tissues and highlighted its applicability in reference material preparation where removal of biological activity is of importance. PMID:25086341

  1. Evaluation of Passive Samplers as a Monitoring Tool for Early Warning of Dinophysis Toxins in Shellfish

    PubMed Central

    Pizarro, Gemita; Moroño, Ángeles; Paz, Beatriz; Franco, José M.; Pazos, Yolanda; Reguera, Beatriz

    2013-01-01

    From June 2006 to January 2007 passive samplers (solid phase adsorbing toxin tracking, SPATT) were tested as a monitoring tool with weekly monitoring of phytoplankton and toxin content (liquid chromatography–mass spectrometry, LC-MS) in picked cells of Dinophysis and plankton concentrates. Successive blooms of Dinophysis acuminata, D. acuta and D. caudata in 2006 caused a long mussel harvesting closure (4.5 months) in the Galician Rías (NW Spain) and a record (up to 9246 ng·g resin-week−1) accumulation of toxins in SPATT discs. Best fit of a toxin accumulation model was between toxin accumulation in SPATT and the product of cell densities by a constant value, for each species of Dinophysis, of toxin content (average) in picked cells. Detection of Dinophysis populations provided earlier warning of oncoming diarrhetic shellfish poisoning (DSP) outbreaks than the SPATT, which at times overestimated the expected toxin levels in shellfish because: (i) SPATT accumulated toxins did not include biotransformation and depuration loss terms and (ii) accumulation of toxins not available to mussels continued for weeks after Dinophysis cells were undetectable and mussels were toxin-free. SPATT may be a valuable environmental monitoring and research tool for toxin dynamics, in particular in areas with no aquaculture, but does not provide a practical gain for early warning of DSP outbreaks. PMID:24152559

  2. Paralytic Shellfish Toxins in Protogonyaulax tamarensis and Protogonyaulax catenella in Axenic Culture 1

    PubMed Central

    Boczar, Barbara A.; Beitler, Mark K.; Liston, John; Sullivan, John J.; Cattolico, Rose Ann

    1988-01-01

    Paralytic shellfish toxin concentrations were measured and individual toxin profiles were monitored in axenic batch cultures of Protogonyaulax tamarensis and Protogonyaulax catenella. High pressure liquid chromatographic methods were used that allowed the separation of all 12 known paralytic shellfish poisons, including toxins C1, C2, and C3, from a single sample. In isolates of both Protogonyaulax species, total toxin levels were relatively low after inoculation, increased rapidly in early to mid-exponential growth to a value 100 to 300% of that at the initial time point, then decreased by 86 to 95% as the culture aged. Although the concentrations of individual toxins per cell followed the same general pattern as that seen for total moles of toxin per cell, variability in toxin profile with culture age was observed. In P. tamarensis, the mole percent of neosaxitoxin increased substantially from 8 to 44% as total toxin levels per cell decreased. A concomitant decrease in the mole percent of saxitoxin with culture age was noted. Although not as precipitous, changes in the mole percent of specific toxins from P. catenella were also observed. The mole percent of gonyautoxins I and IV increased, while that of gonyautoxins II and III decreased. These data suggest that the toxin profile in isolates of Protogonyaulax can change, sometimes significantly, with changing environmental variables. PMID:16666456

  3. Aquaculture: Incorporating risk assessment and risk management into public policies on genetically modified finfish and shellfish

    SciTech Connect

    Hallerman, E.M.; Kapuscinski, A.R.

    1995-12-31

    Genetically modified finfish and shellfish pose economic benefits to aquaculture, but also pose ecological and genetic risks to ecosystems receiving such organisms. Realization of benefits with minimization of risks posed by a new technology can be addressed through the processes of risk assessment and risk management. Public policies adopted by individual countries will reflect differences in the outocme of risk assessment and risk management processes resulting from differences among the receiving ecosystems and sets of human values at issue. A number of countries and international institutions have begun development of policies for oversight of genetically modified aquatic organisms. In the United States, a working group commissioned by the U.S. Department of Agriculture incorporated risk assessment and risk management principles into draft performance standards for safely conducting research with genetically modified finfish and shellfish. The performance standards address research with a broad range of aquatic GMO`s and compliance is intended to be voluntary. In contrast, the Canadian policy mandates adherence to specified guidelines for experiments with transgenic aquatic organisms; establishment as national policy is expended soon.

  4. Bioaccumulation efficiency, tissue distribution, and environmental occurrence of hepatitis E virus in bivalve shellfish from France.

    PubMed

    Grodzki, Marco; Schaeffer, Julien; Piquet, Jean-Côme; Le Saux, Jean-Claude; Chevé, Julien; Ollivier, Joanna; Le Pendu, Jacques; Le Guyader, Françoise S

    2014-07-01

    Hepatitis E virus (HEV), an enteric pathogen of both humans and animals, is excreted by infected individuals and is therefore present in wastewaters and coastal waters. As bivalve molluscan shellfish are known to concentrate viral particles during the process of filter feeding, they may accumulate this virus. The bioaccumulation efficiencies of oysters (Crassostrea gigas), flat oysters (Ostrea edulis), mussels (Mytilus edulis), and clams (Ruditapes philippinarum) were compared at different time points during the year. Tissue distribution analysis showed that most of the viruses were concentrated in the digestive tissues of the four species. Mussels and clams were found to be more sensitive to sporadic contamination events, as demonstrated by rapid bioaccumulation in less than 1 h compared to species of oysters. For oysters, concentrations increased during the 24-h bioaccumulation period. Additionally, to evaluate environmental occurrence of HEV in shellfish, an environmental investigation was undertaken at sites potentially impacted by pigs, wild boars, and human waste. Of the 286 samples collected, none were contaminated with hepatitis E virus, despite evidence that this virus is circulating in some French areas. It is possible that the number of hepatitis E viral particles discharged into the environment is too low to detect or that the virus may have a very short period of persistence in pig manure and human waste. PMID:24795382

  5. [Paralytic shellfish poisoning by Spondylus calcifer contaminated with Pyrodinium bahamense, Costa Rica, 1989-1990].

    PubMed

    Mata, L; Abarca, G; Marranghello, L; Víquez, R

    1990-06-01

    This paper describes an outbreak of paralytic shellfish poisoning (PSP), affecting human populations on the Pacific Coast of Costa Rica in October 1989. Numbness in arms, face and legs occurred 30 to 45 minutes after ingestion of the large clam Spondylus calcifer. Paralysis of legs and respiratory symptoms followed, often persisting for one week. Large amounts of the dinoflagellate Pyrodinium bahamense were found in the intestine of the mollusk. A toxin was detected in crude or filtered and heated macerates of intestine, muscle, mantle and hepatopancreas of S. calcifer, and to a lesser extent Tagelus sp., by injection of its crude or diluted extracts in white mice. The effects in mice consisted in paralysis and asphyxia generally leading to death in less than 5 minutes, compatible with saxitoxin. Mice were killed by the toxin in macerates diluted 1:100 to 1:1000. No toxin was detected in Anadara tuberculosa (Bivalvia) or in peneids. Prevention rests on intersectoral actions between state and private sectors in charge of fishing, distribution and marketing of shellfish, as well as on education of the population at large. PMID:2093952

  6. [Towards a dialogue of knowledge between subsistence fishermen, shellfish gatherers and environmental labor law].

    PubMed

    Carvalho, Ingrid Gil Sales; Rêgo, Rita de Cássia Franco; Larrea-Killinger, Cristina; da Rocha, Júlio César de Sá; Pena, Paulo Gilvane Lopes; Machado, Louise Oliveira Ramos

    2014-10-01

    The dialogue of knowledge between subsistence fishermen and shellfish gatherers on the right to a healthy working environment is established as a new process for claims for an improvement in working conditions by populations affected by environmental problems, and especially in Todos os Santos Bay (BTS). The communities surrounding the BTS have complained to the State Public Prosecutor about the harmful effects to health and the environment caused by the Aratu Industrial Complex and the Port of Aratu. Researchers in the fields of, chemistry, toxicology, oceanography, biology and medicine from the Federal University of Bahia (UFBA) have demonstrated the effects of contamination on the BTS in sundry scientific publications. The scope of this article is to reflect on the contribution of that dialogue on environmental labor law (DAT) in Brazil. The methodology of this study involved semi-structured interviews, participant observation and document analysis. The conclusion reached is that environmental labor law in Brazil must include the dialogue of knowledge to ensure access to a healthy working environment for subsistence fishermen and shellfish gatherers. PMID:25272110

  7. Collaborative evaluation of a method for the detection of Norwalk virus in shellfish tissues by PCR.

    PubMed Central

    Atmar, R L; Neill, F H; Woodley, C M; Manger, R; Fout, G S; Burkhardt, W; Leja, L; McGovern, E R; Le Guyader, F; Metcalf, T G; Estes, M K

    1996-01-01

    A multicenter, collaborative trial was performed to evaluate the reliability and reproducibility of a previously described method for the detection of Norwalk virus in shellfish tissues with the PCR (R.L. Atmar, F. H. Neill, J. L. Romalde, F. Le Guyader, C. M. Woodley, T. G. Metcalf, and M. K. Estes, Appl. Environ. Microbiol. 61:3014-3018, 1995). Virus was added to the stomachs and hepatopancreatic tissues of oysters or hard-shell clams in the control laboratory, the samples were shipped to the participating laboratories, and viral nucleic acids were extracted and then detected by reverse transcription-PCR. The sensitivity and specificity of the assay were 85 and 91%, respectively, when results were determined by visual inspection of ethidium bromide-stained agarose gels; the test sensitivity and specificity improved to 87 and 100%, respectively, after confirmation by hybridization with a digoxigenin-labeled, virus-specific probe. We have demonstrated that this method can be implemented successfully by several laboratories to detect Norwalk virus in shellfish tissues. PMID:8572702

  8. Apparent bioaccumulation of cylindrospermopsin and paralytic shellfish toxins by finfish in Lake Catemaco (Veracruz, Mexico).

    PubMed

    Berry, J P; Jaja-Chimedza, A; Dávalos-Lind, L; Lind, O

    2012-01-01

    Compared to the well-characterized health threats associated with contamination of fish and shellfish by algal toxins in marine fisheries, the toxicological relevance of the bioaccumulation of toxins from cyanobacteria (blue-green algae), as the primary toxigenic algae in freshwater systems, remains relatively unknown. Lake Catemaco (Veracruz, Mexico) is a small, tropical lake system specifically characterized by a year-round dominance of the known toxigenic cyanobacterial genus, Cylindrospermopsis, and by low, but detectable, levels of both a cyanobacterial hepatotoxin, cylindrospermopsin (CYN), and paralytic shellfish toxins (PSTs). In the present study, we evaluated, using enzyme-linked immunoassay (ELISA), levels of both toxins in several species of finfish caught and consumed locally in the region to investigate the bioaccumulation of, and possible health threats associated with, these toxins as potential foodborne contaminants. ELISA detected levels of both CYN and PSTs in fish tissues from the lake. Levels were generally low (≤ 1 ng g(-1) tissue); however, calculated bioaccumulation factors (BAFs) indicate that toxin levels exceed the rather low levels in the water column and, consequently, indicated bioaccumulation (BAF >1). A reasonable correlation was observed between measured bioaccumulation of CYN and PSTs, possibly indicating a mutual source of both toxins, and most likely cells of Cylindrospermopsis, the dominant cyanobacteria in the lake, and a known producer of both metabolites. The potential roles of trophic transport in the system, as well as possible implications for human health with regards to bioaccumulation, are discussed. PMID:21838624

  9. Radioactive contamination of fish, shellfish, and waterfowl exposed to Hanford effluents: Annual summaries, 1945--1972

    SciTech Connect

    Hanf, R.W.; Dirkes, R.L.; Duncan, J.P.

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction Project (HEDR) is to estimate the potential radiation doses received by people living within the sphere of influence of the Hanford Site. A potential critical pathway for human radiation exposure is through the consumption of waterfowl that frequent onsite waste-water ponds or through eating of fish, shellfish, and waterfowl that reside in/on the Columbia River and its tributaries downstream of the reactors. This document summarizes information on fish, shellfish, and waterfowl radiation contamination for samples collected by Hanford monitoring personnel and offsite agencies for the period 1945 to 1972. Specific information includes the types of organisms sampled, the kinds of tissues and organs analyzed, the sampling locations, and the radionuclides reported. Some tissue concentrations are also included. We anticipate that these yearly summaries will be helpful to individuals and organizations interested in evaluating aquatic pathway information for locations impacted by Hanford operations and will be useful for planning the direction of future HEDR studies.

  10. Vitamin D levels in fish and shellfish determined by liquid chromatography with ultraviolet detection and mass spectrometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin D3 (cholecalciferol) levels were determined in finfish and shellfish using UV detection at 265nm (combined with auxiliary full scan UV detection) and selected ion monitoring (SIM) mass spectrometry (MS), using vitamin D2 (ergocalciferol) as an internal standard. Analysis of standard referen...

  11. COASTAL*FISH user's guide--a finfish/shellfish information base for Mississippi Sound and Mobile Bay

    USGS Publications Warehouse

    Jones, B.; Benson, N.

    1982-01-01

    COASTAL *FISH is a computerized database that includes current information on spawning, nursery areas, migrations, distribution, and environmental requirements of finfish and shellfish. This User's Guide was prepared to access and query the finfish and shell fish database. It provides basic information required to query the database.

  12. Use of sodium dodecyl sulfate-polymyxin B-sucrose medium for isolation of Vibrio vulnificus from shellfish.

    PubMed

    Bryant, R G; Jarvis, J; Janda, J M

    1987-07-01

    The differential and selective sodium dodecyl sulfate-polymyxin B-sucrose medium (SPS) of Kitaura et al. (T. Kitaura, S. Doke, I. Azuma, M. Imaida, K. Miyano, K. Harada, and E. Yabuuchii, FEMS Microbiol. Lett. 17:205-209, 1983), which highlights alkylsulfatase activity, was evaluated for its potential use in the direct isolation and enumeration of Vibrio vulnificus from shellfish. V. vulnificus was detected by this method in six of nine shellfish samples collected from diverse geographic locales during the summer of 1986. Direct enumeration of V. vulnificus at 7.0 X 10(2) to 2.2 X 10(4) CFU/g of shellfish was achieved on SPS agar. All sample results were confirmed in parallel examinations by using conventional glucose-salt-Teepol (Shell Oil Co.) broth and alkaline peptone water enrichment with plating onto thiosulfate-citrate-bile salts-sucrose agar. Additionally, alkylsulfatase activity was evaluated in vitro for 97 strains representing 14 Vibrio spp. V. vulnificus and Vibrio cholerae-01 were the only species consistently found to possess this activity. The range of plating efficiencies for random V. vulnificus strains analyzed on SPS was 11 to 74% (mean, 39%). The use of SPS shows great promise for the study of shellfish and other environmental sources for V. vulnificus. PMID:3662506

  13. The first evidence of paralytic shellfish toxins in the fresh water cyanobacterium Cylindrospermopsis raciborskii, isolated from Brazil.

    PubMed

    Lagos, N; Onodera, H; Zagatto, P A; Andrinolo, D; Azevedo, S M; Oshima, Y

    1999-10-01

    The blooms of toxic cyanobacteria (blue-green algae) are causing problems in many countries. During a screening of toxic freshwater cyanobacteria in Brazil, three strains isolated from the State of Sao Paulo were found toxic by the mouse bioassay. They all were identified as Cylindrospermopsis raciborskii by a close morphological examination. Extracts of cultured cells caused acute death to mice when injected intraperitoneally after developing neurotoxic symptoms which resembled to those caused by paralytic shellfish toxins. The analysis of the sample by HPLC-FLD postcolumn derivatization method for paralytic shellfish toxins resulted in the detection of several saxitoxin analogs. To avoid being misled by false peaks, the sample was reanalyzed after purification and also under the different postcolumn derivatizing conditions. Finally, the newly developed LC-MS method for paralytic shellfish toxins was applied to unambiguously identify the toxins. One isolate produced neosaxitoxin predominantly with saxitoxin as a minor component. The other two showed identical toxin profiles containing saxitoxin and gonyautoxins 2/3 isomers in the ratio of 1:9. This is the first evidence of paralytic shellfish toxins in this species and also the occurrence of the toxin producing cyanobacterium in South American countries. PMID:10414862

  14. Use of sodium dodecyl sulfate-polymyxin B-sucrose medium for isolation of Vibrio vulnificus from shellfish.

    PubMed Central

    Bryant, R G; Jarvis, J; Janda, J M

    1987-01-01

    The differential and selective sodium dodecyl sulfate-polymyxin B-sucrose medium (SPS) of Kitaura et al. (T. Kitaura, S. Doke, I. Azuma, M. Imaida, K. Miyano, K. Harada, and E. Yabuuchii, FEMS Microbiol. Lett. 17:205-209, 1983), which highlights alkylsulfatase activity, was evaluated for its potential use in the direct isolation and enumeration of Vibrio vulnificus from shellfish. V. vulnificus was detected by this method in six of nine shellfish samples collected from diverse geographic locales during the summer of 1986. Direct enumeration of V. vulnificus at 7.0 X 10(2) to 2.2 X 10(4) CFU/g of shellfish was achieved on SPS agar. All sample results were confirmed in parallel examinations by using conventional glucose-salt-Teepol (Shell Oil Co.) broth and alkaline peptone water enrichment with plating onto thiosulfate-citrate-bile salts-sucrose agar. Additionally, alkylsulfatase activity was evaluated in vitro for 97 strains representing 14 Vibrio spp. V. vulnificus and Vibrio cholerae-01 were the only species consistently found to possess this activity. The range of plating efficiencies for random V. vulnificus strains analyzed on SPS was 11 to 74% (mean, 39%). The use of SPS shows great promise for the study of shellfish and other environmental sources for V. vulnificus. Images PMID:3662506

  15. UTILIZING SHELLFISH RESPONSES TO SET TARGET WATER QUALITY CONDITIONS FOR THE RESTORATION OF OYSTER REEFS IN THE CALOOSAHATCHEE ESTUARY, FLORIDA.

    EPA Science Inventory

    Volety, Aswani K., S.G. Tolley and James T. Winstead. 2002. Utilizing Shellfish Responses to Set Target Water Quality Conditions for the Restoration of Oyster Reefs in the Caloosahatchee Estuary, Florida. Presented at the International Workshop on Restoration of Benthic Invertebr...

  16. Ranking the contributions of commercial fish and shellfish varieties to mercury exposure in the United States: implications for risk communication.

    PubMed

    Groth, Edward

    2010-04-01

    Fish and shellfish have important nutritional benefits, and US per capita seafood consumption has increased substantially since 2002. Recent research has reinforced concerns about adverse effects of methylmercury exposure, suggesting that methylmercury doses associated with typical US rates of fish consumption may pose measurable risks, with no threshold. These converging trends create a need to improve risk communication about fish consumption and mercury. The analysis performed here identifies the relative importance of different fish and shellfish as sources of mercury in the US seafood supply and proposes improved consumer advice, so that the public can benefit from fish consumption while minimizing mercury exposure. I have quantified contributions to total mercury in the US seafood supply by 51 different varieties of fish and shellfish, then ranked and sorted the 51 varieties in terms of relative impact. Except for swordfish, most fish with the highest mercury levels are relatively minor contributors to total inputs. Tuna (canned light, canned albacore and fresh/frozen varieties) accounts for 37.4 percent of total mercury inputs, while two-thirds of the seafood supply and nine of the 11 most heavily consumed fish and shellfish are low or very low in mercury. Substantial improvement in risk communication about mercury in fish and seafood is needed; in particular, several population subsets need better guidance to base their seafood choices more explicitly on mercury content. I have sorted the 51 seafood varieties into six categories based on mercury levels, as a framework for improving risk communication in this regard. PMID:20116785

  17. Application of rapid test kits for the determination of paralytic shellfish poisoning (PSP) toxins in bivalve molluscs from Great Britain.

    PubMed

    Harrison, Keith; Johnson, Sarah; Turner, Andrew D

    2016-09-01

    Six different commercial rapid screening assays for Paralytic Shellfish Poisoning toxins were assessed with the analysis of shellfish samples from GB. The performance of each kit was assessed through comparison with the current regulatory HPLC method. Samples assessed consisted of a wide variety of shellfish species of importance to the shellfish industry in GB. These had been sourced over a number of years and with a wide variety of geographical origins. One lateral flow immunoassay was found to provide a quick qualitative assessment of PSP toxicity, with a low proportion of false negative results for PSP-positive samples, but with higher numbers of false positives. The performance of the five quantitative ELISA assays varied considerably, with two demonstrating an inappropriate linear range, with others either over-estimating or under-estimating toxicity. One ELISA from R-Biopharm was found to show a good correlation with the HPLC toxicity results. All ELISAs, however, returned some false negative results, most notably for samples containing high proportions of toxins with low cross reactivity to saxitoxin such as GTX1&4. Whilst the lateral flow assays on the market are of particular use to Food Business Operators for end product testing, further work is required in parallel with instrumental testing methods using a larger number of samples to assess the reliability and accuracy of these kits over the long term. PMID:27373993

  18. Determination of diarrheic shellfish toxins in mussels by microliquid chromatography-tandem mass spectrometry.

    PubMed

    Draisci, R; Lucentini, L; Giannetti, L; Boria, P; James, K J; Furey, A; Gillman, M; Kelly, S S

    1998-01-01

    A fast, sensitive, and specific procedure for determining toxins that cause diarrheic shellfish poisoning (DSP) using microliquid chromatography coupled with tandem mass spectrometry (micro-LC-MS-MS) is reported. The lipophylic polyether acidic toxins okadaic acid (OA), its isomer dinophysistoxin-2 (DTX-2), the 35-methylokadaic acid dinophysistoxin-1 (DTX-1), and the novel toxin dinophysistoxin-1B (DTX-2B; recently isolated from Irish mussels) were extracted from shellfish tissues with acetone and chromatographed by isocratic elution at 10 microL/min with CH3 CN-H2O, 80 + 20 (v/v), containing 0.1% trifluoroacetic acid, through a C18 reversed-phase column (1.0 mm id). The chromatograph is coupled via an ion spray interface to an atmospheric pressure ionization source. Collision-induced-dissociation (CID) ion mass spectra of the protonated molecule, [M + H]+, at m/z 805 for OA, DTX-2, and DTX-2B and at m/z 819 for DTX-1, were obtained in MS-MS experiments to identify 2 diagnostic fragment ions for each analyte that could be used for selected-reaction-monitoring (SRM) micro-LC-MS-MS analysis. The CID spectrum of DTX-2B confirmed it to be a new OA isomer, like DTX-2. Standard curves obtained by SRM micro-LC-MS-MS were linear (r2 > or = 0.9992) over the range 0.05-1.00 micrograms/mL (i.e., 0.10-2.00 micrograms toxin/g hepatopancreas), and a detection limit of 15 pg/injection was obtained for each DSP toxin. Average recoveries ranged from 95 to 101%, and coefficients of variation ranged from 1.8 to 3.4%. This novel SRM micro-LC-MS-MS method was used to confirm acidic DSP toxins in Irish and Italian toxic mussels. It offers a high degree of specificity because analyte confirmation is based on retention time, molecular weight, structural information obtained from the presence of 2 diagnostic fragments for each analyte, and ion ratios. OA was found in both Irish (< or = 0.7 micrograms/g hepatopancreas) and Italian (< or = 1.5 micrograms/g hepatopancreas) mussels. DTX-1 was

  19. Climate relationships to fecal bacterial densities in Maryland shellfish harvest waters.

    PubMed

    Leight, A K; Hood, R; Wood, R; Brohawn, K

    2016-02-01

    Coastal states of the United States (US) routinely monitor shellfish harvest waters for types of bacteria that indicate the potential presence of fecal pollution. The densities of these indicator bacteria in natural waters may be related to climate in several ways, including through runoff from precipitation and survival related to water temperatures. The relationship between interannual precipitation and air temperature patterns and the densities of fecal indicator bacteria in shellfish harvest waters in Maryland's portion of the Chesapeake Bay was quantified using 34 years of data (1979-2013). Annual and seasonal precipitation totals had a strong positive relationship with average fecal coliform levels (R(2) = 0.69) and the proportion of samples with bacterial densities above the FDA regulatory criteria (R(2) = 0.77). Fecal coliform levels were also significantly and negatively related to average annual air temperature (R(2) = -0.43) and the average air temperature of the warmest month (R(2) = -0.57), while average seasonal air temperature was only significantly related to fecal coliform levels in the summer. River and regional fecal coliform levels displayed a wide range of relationships with precipitation and air temperature patterns, with stronger relationships in rural areas and mainstem Bay stations. Fecal coliform levels tended to be higher in years when the bulk of precipitation occurred throughout the summer and/or fall (August to September). Fecal coliform levels often peaked in late fall and winter, with precipitation peaking in summer and early fall. Continental-scale sea level pressure (SLP) analysis revealed an association between atmospheric patterns that influence both extratropical and tropical storm tracks and very high fecal coliform years, while regional precipitation was found to be significantly correlated with the Atlantic Multidecadal Oscillation and the Pacific North American Pattern. These findings indicate that management of

  20. Occurrence of pathogenic Vibrio parahaemolyticus in crustacean shellfishes in coastal parts of Eastern India

    PubMed Central

    Parthasarathy, S.; Das, Suresh Chandra; Kumar, Ashok

    2016-01-01

    Aim: The objective of the study was to isolate and characterize pathogenic Vibrio parahaemolyticus from crustacean shellfishes (crab and shrimp) commonly retailed in coastal parts of eastern India. Materials and Methods: Samples were processed by bacteriological isolation followed by biochemical characterization in Kaper’s medium. Presumptively identified isolates were confirmed by species-specific Vp-toxR polymerase chain reaction (PCR) assay. Virulence and pandemic property of the confirmed V. parahaemolyticus isolates were determined by specific PCR assays. Results: On screening of 167 samples comprising crabs (n=82) and shrimps (n=85) by the standard bacteriological cultural method, V. parahaemolyticus was presumptively identified in 86.6% (71/82) and 82.3% (70/85) of respective samples. Of these, 46 (56%) and 66 (77.6%) isolates from crab and shrimp, respectively, were confirmed as V. parahaemolyticus by biochemical characterization (Kaper’s reaction) followed by specific Vp-toxR PCR assay. About 10 isolates each from crab and shrimp was found to carry the virulence gene (tdh). It denotes that 12.2% of crab and 11.7% of shrimp in the study area are harboring the pathogenic V. parahaemolyticus. Such tdh+ isolates (n=20) were subjected for screening of pandemic genotype by pandemic group specific (PGS) - PCR (PGS-PCR) and GS-PCR (toxRS gene) where 11 (6.5%) isolates revealed the pandemic determining amplicon (235 bp) in PGS-PCR and belonged to crab (7.3%) and shrimp (6%) samples; however, 2 (2.4%) isolates were positive in GS-PCR and belonged to crab samples only. These two GS-PCR+ isolates from crab were also positive in PGS-PCR. Conclusion: The findings of the study conclusively indicated that a considerable percentage of crab and shrimp in these areas were harboring pathogenic and pandemic V. parahaemolyticus posing a public health risk in consumption of improperly processed such shellfishes. Cross contamination of other marine and fresh water market

  1. Accumulation and depuration of paralytic shellfish poisoning toxins by laboratory cultured purple clam Hiatula diphos Linnaeus.

    PubMed

    Chou, Hong Nong; Huang, Chen Ping; Chen, Chih Yu

    2005-10-01

    Purple clams (Hiatula diphos Linnaeus) accumulate paralytic shellfish poisoning (PSP) toxins produced by a toxic strain of the dinoflagellate Alexandrium minutum Halim in a laboratory study. The maximal toxicity of PSP toxins attained 31.3m MU/g after 20 days exposure. The toxin profile of H. diphos was similar to that reported for A. minutum at the end of the exposure period; and GTX1 was dominant. GTX congeners were found in muscle on day 16 and day 20, these substances could be detected during the depuration period as well. GTX1 was detected in the siphon only on day 32. The results show that H. diphos accumulates PSP toxins according to the amount and toxin profile of ingested A. minutum. PMID:16137734

  2. kappa-Carrageenan gel as agent to sequester paralytic shellfish poison.

    PubMed

    Cañete, Socrates Jose P; Montaño, Marco Nemesio E

    2002-12-01

    The action of k-carrageenan gel to sequester paralytic shellfish poison (PSP) was tested and characterized. When an extract from a Philippine strain of Pyrodinium bahamense var. compressum was used as PSP solution, the PSP-sequestering property of kappa-carrageenan gel was found to be dependent on gel surface area, interaction time, and polysaccharide concentration. The interaction was also found to be affected by high concentrations of monovalent cations. The characteristics of kappa-carrageenan as a PSP-sequestering agent all point to cation exchange as its mechanism of action. It is also proposed that the polysaccharide gel can be utilized as an agent to alleviate PSP intoxication. PMID:14961231

  3. Trace metal residues in shellfish from Maryland waters, 1976-1980

    SciTech Connect

    Eisenberg, M.; Topping, J.J.

    1984-10-01

    Levels of seven heavy metal residues, arsenic, cadmium, chromium, copper, lead, mercury and zinc were monitored in samples of the American oyster (Crassostrea virginica), the soft shell clam (Mya arenaria), the hard shell clam (Mercenaria mercenaria) and the blue crab (Callinectes sapidus). The study was conducted from 1976 through 1980. In cases where the Food and Drug Administration has established action levels, mean and median yearly values were significantly below these levels. In cases where no action level exists, heavy metal residues in the shellfish samples were well below levels which are generally regarded as safe. No significant yearly trends in heavy metal residues were discovered. Apparent increases in arsenic levels merit further study. 22 references, 1 figure, 3 tables.

  4. Development of shellfish removing machine for large-diameter sea-water piping

    SciTech Connect

    Murakami, Seiichi; Nakazawa, Toyohiko; Watanabe, Seiji

    1996-08-01

    At nuclear and thermal power plants, the large amount of marine organisms that grow on the inside of condenser cooling, sea-water pipes, such as blue mussels and barnacles, significantly increases the pressure loss of the fluid in the pipes. This causes a deterioration in pumping efficiency and causes damage and corrosion to the paint coating on the inside of the pipes. These marine organisms must be removed, and this takes place by hand during each scheduled outage of the power plants. The working environment within these long lengths of large-diameter pipes is very harsh, requiring a great deal of time and physical labor to remove these organisms. Moreover, finding people to perform this task is becoming difficult. For these reasons. There has been a strong desire to mechanize this task. And this led to the development of a shellfish removing machine for these large-diameter sea-water pipes. The most important considerations in developing this machine were that the removal of the marine organisms be efficient and that the method of removal cause minimum damage to the coating on the inside of the pipes. Good results were obtained using a special cleaning brush that has a removing fixture attached to the end of a wire rope. After several application tests, the machine was used to remove shellfish from condenser cooling sea-water pipes during the sixth scheduled outage of the Japan Atomic Power Company`s Tsuruga No. 2 Unit in September, 1994. There, the capability and reliability of this machine were verified

  5. Lethal paralytic shellfish poisoning from consumption of green mussel broth, Western Samar, Philippines, August 2013

    PubMed Central

    Ramos, Ruth Alma; de los Reyes, Vikki Carr; Sucaldito, Ma Nemia; Tayag, Enrique

    2015-01-01

    Background In July 2013, the Philippines’ Event-Based Surveillance & Response Unit received a paralytic shellfish poisoning (PSP) report from Tarangnan, Western Samar. A team from the Department of Health conducted an outbreak investigation to identify the implicated source and risk factors in coastal villages known for green mussel production and exportation. Methods A case was defined as a previously well individual from Tarangan, Western Samar who developed gastrointestinal symptoms and any motor and/or sensory symptoms after consumption of shellfish from 29 June to 4 July 2013 in the absence of any known cause. The team reviewed medical records, conducted active case finding and a case-control study. Relatives of cases who died were interviewed. Sera and urine specimens, green mussel and seawater samples were tested for saxitoxin levels using high performance liquid chromatography. Results Thirty-one cases and two deaths were identified. Consumption of > 1 cup of green mussel broth was associated with being a case. Seawater sample was positive for Pyrodinium bahamense var. compressum and green mussel samples were positive for saxitoxin. Inspection revealed villagers practice open defecation and improper garbage disposal. Conclusion This PSP outbreak was caused by the consumption of the green mussel broth contaminated by saxitoxin. As a result of this outbreak, dinoflagellate and saxitoxin surveillance was established, and since the outbreak, there have been no harmful algal blooms event or PSP case reported since. A “Save Cambatutay Bay” movement, focusing on proper waste disposal practice and clean-up drives has been mobilized. PMID:26306212

  6. Contamination of commercially available seafood by key diarrhetic shellfish poisons along the coast of China.

    PubMed

    Lin, Chao; Liu, Zeng-Shan; Tan, Cai-Yun; Guo, Yi-Ping; Li, Lin; Ren, Hong-Lin; Li, Yan-Song; Hu, Pan; Gong, Sheng; Zhou, Yu; Lu, Shi-Ying

    2015-01-01

    With the increasing number of outbreaks of food-borne diseases caused by okadaic acid (OA) and its analogue dinophysistoxin-1 (DTX-1), two key diarrhetic shellfish poison (DSP) toxins, OA and DTX-1, have become a serious threat to public health and have attracted significant public attention in China. The aim of our study was to monitor OA and DTX-1 contamination in commercially available seafood and to provide references for tracking these toxins and preventing disease outbreaks. From 2010 to 2012, 40 species were collected from six coastal cities of four inland seas in China. An enzyme-linked immunosorbent assay (ELISA) and a lateral flow immunochromatographic (LFIC) test strip were used to analyse the samples, and the results were further confirmed using a commercially available ELISA kit. The monitoring results indicated that 23 of 40 species were positive for contamination. In addition, 14 of the positive species were determined to be inedible because the content of OA and DTX-1 was above the regulatory limit. Simultaneously, we verified that the digestive glands of shellfish tended to accumulate toxin, in contrast to the flesh. The highest concentrations of OA and DTX-1 were recorded in Scapharca broughtonii, which was collected from Qing Dao, in relation to the other analysed species. Moreover, the Arca family as well as Mytilus galloprovincialis were severely contaminated by OA and its analogue. The above results indicate that some of the commercially available seafood from the coastal cities in China may be inedible due to serious marine toxin contamination. The results of this study might play an important role in protecting consumer health and safety screening of marine products. PMID:25167824

  7. Long-Term Study of Vibrio parahaemolyticus Prevalence and Distribution in New Zealand Shellfish

    PubMed Central

    Hedderley, D.; Fletcher, G. C.

    2015-01-01

    The food-borne pathogen Vibrio parahaemolyticus has been reported as being present in New Zealand (NZ) seawaters, but there have been no reported outbreaks of food-borne infection from commercially grown NZ seafood. Our study determined the current incidence of V. parahaemolyticus in NZ oysters and Greenshell mussels and the prevalence of V. parahaemolyticus tdh and trh strains. Pacific (235) and dredge (21) oyster samples and mussel samples (55) were obtained from commercial shellfish-growing areas between December 2009 and June 2012. Total V. parahaemolyticus numbers and the presence of pathogenic genes tdh and trh were determined using the FDA most-probable-number (MPN) method and confirmed using PCR analysis. In samples from the North Island of NZ, V. parahaemolyticus was detected in 81% of Pacific oysters and 34% of mussel samples, while the numbers of V. parahaemolyticus tdh and trh strains were low, with just 3/215 Pacific oyster samples carrying the tdh gene. V. parahaemolyticus organisms carrying tdh and trh were not detected in South Island samples, and V. parahaemolyticus was detected in just 1/21 dredge oyster and 2/16 mussel samples. Numbers of V. parahaemolyticus organisms increased when seawater temperatures were high, the season when most commercial shellfish-growing areas are not harvested. The numbers of V. parahaemolyticus organisms in samples exceeded 1,000 MPN/g only when the seawater temperatures exceeded 19°C, so this environmental parameter could be used as a trigger warning of potential hazard. There is some evidence that the total V. parahaemolyticus numbers increased compared with those reported from a previous 1981 to 1984 study, but the analytical methods differed significantly. PMID:25616790

  8. Long-term study of Vibrio parahaemolyticus prevalence and distribution in New Zealand shellfish.

    PubMed

    Cruz, C D; Hedderley, D; Fletcher, G C

    2015-04-01

    The food-borne pathogen Vibrio parahaemolyticus has been reported as being present in New Zealand (NZ) seawaters, but there have been no reported outbreaks of food-borne infection from commercially grown NZ seafood. Our study determined the current incidence of V. parahaemolyticus in NZ oysters and Greenshell mussels and the prevalence of V. parahaemolyticus tdh and trh strains. Pacific (235) and dredge (21) oyster samples and mussel samples (55) were obtained from commercial shellfish-growing areas between December 2009 and June 2012. Total V. parahaemolyticus numbers and the presence of pathogenic genes tdh and trh were determined using the FDA most-probable-number (MPN) method and confirmed using PCR analysis. In samples from the North Island of NZ, V. parahaemolyticus was detected in 81% of Pacific oysters and 34% of mussel samples, while the numbers of V. parahaemolyticus tdh and trh strains were low, with just 3/215 Pacific oyster samples carrying the tdh gene. V. parahaemolyticus organisms carrying tdh and trh were not detected in South Island samples, and V. parahaemolyticus was detected in just 1/21 dredge oyster and 2/16 mussel samples. Numbers of V. parahaemolyticus organisms increased when seawater temperatures were high, the season when most commercial shellfish-growing areas are not harvested. The numbers of V. parahaemolyticus organisms in samples exceeded 1,000 MPN/g only when the seawater temperatures exceeded 19°C, so this environmental parameter could be used as a trigger warning of potential hazard. There is some evidence that the total V. parahaemolyticus numbers increased compared with those reported from a previous 1981 to 1984 study, but the analytical methods differed significantly. PMID:25616790

  9. Most-probable-number loop-mediated isothermal amplification-based procedure enhanced with K antigen-specific immunomagnetic separation for quantifying tdh(+) Vibrio parahaemolyticus in molluscan Shellfish.

    PubMed

    Tanaka, Natsuko; Iwade, Yoshito; Yamazaki, Wataru; Gondaira, Fumio; Vuddhakul, Varaporn; Nakaguchi, Yoshitsugu; Nishibuchi, Mitsuaki

    2014-07-01

    Although thermostable direct hemolysin-producing (tdh(+)) Vibrio parahaemolyticus is the leading cause of seafood-borne gastroenteritis, the enumeration of tdh(+) V. parahaemolyticus remains challenging due to its low densities in the environment. In this study, we developed a most-probable-number (MPN)-based procedure designated A-IS(1)-LAMP, in which an immunomagnetic separation (IMS) technique targeting as many as 69 established K antigens and a loop-mediated isothermal amplification (LAMP) assay targeting the thermostable direct hemolysin (tdh) gene were applied in an MPN format. Our IMS employed PickPen, an eight-channel intrasolution magnetic particle separation device, which enabled a straightforward microtiter plate-based IMS procedure (designated as PickPen-IMS). The ability of the procedure to quantify a wide range of tdh(+) V. parahaemolyticus levels was evaluated by testing shellfish samples in Japan and southern Thailand, where shellfish products are known to contain relatively low and high levels of total V. parahaemolyticus, respectively. The Japanese and Thai shellfish samples showed, respectively, relatively low (< 3 to 11 MPN/10 g) and considerably higher (930 to 110,000 MPN/10 g) levels of tdh(+) V. parahaemolyticus, raising concern about the safety of Thai shellfish products sold to domestic consumers at local morning markets. LAMP showed similar or higher performance than conventional PCR in the detection and quantification of a wide range of tdh(+) V. parahaemolyticus levels in shellfish products. Whereas a positive effect of PickPen-IMS was not observed in MPN determination, PickPen-IMS was able to concentrate tdh(+) V. parahaemolyticus 32-fold on average from the Japanese shellfish samples at an individual tube level, suggesting a possibility of using PickPen-IMS as an optional tool for specific shellfish samples. The A-IS(1)-LAMP procedure can be used by any health authority in the world to measure the tdh(+) V. parahaemolyticus levels in

  10. The Association between the Consumption of Fish/Shellfish and the Risk of Osteoporosis in Men and Postmenopausal Women Aged 50 Years or Older

    PubMed Central

    Choi, Eunjin; Park, Youngsoon

    2016-01-01

    Fish rich in n-3 polyunsaturated fatty acids have been suggested to have a favorable effect on bone health, but previous epidemiologic studies have shown inconsistent results. The purpose of the present study was to investigate the hypothesis that the consumption of fish and shellfish is positively associated with bone mass and negatively associated with the risk of osteoporosis in Koreans and Americans. Men and postmenopausal women ≥50 years old from the Korean National Health and Nutrition Examination Survey 2008–2011 (n = 7154) and the National Health and Nutrition Examination Survey 2007–2010 (n = 2658) were included. There was a positive correlation between the consumption of fish and shellfish and bone mineral density (BMD) of the total femur, femoral neck, and lumbar spine in Koreans. Consistently, multivariate logistic regression analysis showed a significant association between intake of fish and shellfish and the risk of osteoporosis in Koreans but not in Americans. Consumption of fish and shellfish was 4–5 times higher in Koreans than Americans in the present study. In conclusion, intake of fish and shellfish was associated with BMD and the risk of osteoporosis in Koreans but not in Americans, suggesting that a minimum intake level of fish and shellfish might be recommended to protect against bone loss and osteoporosis. PMID:26927165

  11. Investigation on the differences of accumulating Escherichia coli in three types of shellfish species, involving in the environmental factors.

    PubMed

    Jin, Lei; Li, Tiejun; Liu, Huan; Zhu, Jinping

    2016-08-15

    This study investigated accumulation of Escherichia coli and aerobic colony count in three types of shellfish species. The results indicated that the capability of accumulating E. coli and aerobic colony count for Sinonovacula constricta was stronger than that for Meretrix meretrix and Tegillarca granosa, and capability of accumulating E. coli for M. meretrix was slightly stronger than that for T. granosa. However, no significant difference was observed in the capability of accumulating aerobic colony count between M. meretrix and T. granosa. Moreover, accumulation of E. coli in S. constricta is affected by contaminated seawater and E. coli were accumulated much faster and more in S. constricta when the seawater contaminated more serious. Meanwhile, the results suggested that the populations of E. coli in S. constricta changed in accordance with the weather. This is the first study to investigate the differences of accumulating E. coli in three types of shellfish species. PMID:27283878

  12. Azaspiracid Shellfish Poisoning: A Review on the Chemistry, Ecology, and Toxicology with an Emphasis on Human Health Impacts

    PubMed Central

    Twiner, Michael J.; Rehmann, Nils; Hess, Philipp; Doucette, Gregory J.

    2008-01-01

    Azaspiracids (AZA) are polyether marine toxins that accumulate in various shellfish species and have been associated with severe gastrointestinal human intoxications since 1995. This toxin class has since been reported from several countries, including Morocco and much of western Europe. A regulatory limit of 160 μg AZA/kg whole shellfish flesh was established by the EU in order to protect human health; however, in some cases, AZA concentrations far exceed the action level. Herein we discuss recent advances on the chemistry of various AZA analogs, review the ecology of AZAs, including the putative progenitor algal species, collectively interpret the in vitro and in vivo data on the toxicology of AZAs relating to human health issues, and outline the European legislature associated with AZAs. PMID:18728760

  13. Gas chromatography combined with mass spectrometry for the identification of organic sulfur compounds in shellfish and fish

    SciTech Connect

    Ogata, M.; Miyake, Y.

    1980-11-01

    The authors determined that the organic sulfur compounds usually contained in crude oil can be used as a marker of oil pollution in shellfish and fish. Short-necked clams and eels were maintained in a controlled laboratory environment in water with suspension of crude oil. Mass spectra and mass chromatograms of short-necked clam extract showed the presence of organic sulfur compounds. Capillary column gas chromatography-mass chromatograms of crude oil and extract from the soft body of a short-necked clam showed the presence of organic sulfur compounds. Besides sulfur components, various other compounds were contained in crude oil and short-necked clam. Mass chromatograms of crude oil and the extract from eel flesh showed the presence of alkyl benzothiophene, dibenzothiophene, naphthalene, and alkyl naphthalene. Data indicated that the organic sulfur compounds and polyaromatic compounds could serve as markers of oil pollution in shellfish and fish.

  14. BMAA in shellfish from two Portuguese transitional water bodies suggests the marine dinoflagellate Gymnodinium catenatum as a potential BMAA source.

    PubMed

    Lage, Sandra; Costa, Pedro Reis; Moita, Teresa; Eriksson, Johan; Rasmussen, Ulla; Rydberg, Sara Jonasson

    2014-07-01

    The neurotoxin β-N-methylamino-l-alanine (BMAA) and its putative role in multiple neurodegenerative diseases have been intensely studied since 2005 when the toxin was discovered to be produced by worldwide-distributed cyanobacterial species inhabiting terrestrial, marine, brackish, and freshwater ecosystems. Recently, BMAA production was also associated with one eukaryotic group, namely, diatoms, raising questions about its production by other phytoplanktonic groups. To test for BMAA bioavailability in ecosystems where abundant phytoplanktonic blooms regularly occur, samples of filter-feeding shellfish were collected in two Portuguese transitional water bodies. BMAA content in cockles (Cerastoderma edule) collected weekly between September and November 2009 from Ria de Aveiro and at least once a month from May to November from Ria Formosa, fluctuated from 0.079±0.055 to 0.354±0.066μg/g DW and from below the limit of detection to 0.434±0.110μg/g DW, respectively. Simultaneously to BMAA occurrence in cockles, paralytic shellfish toxins were detected in shellfish as a result of Gymnodinium catenatum blooms indicating a possible link between this marine dinoflagellate and BMAA production. Moreover, considerable high BMAA levels, 0.457±0.186μg/g DW, were then determined in a laboratory grown culture of G. catenatum. This work reveals for the first time the presence of BMAA in shellfish from Atlantic transitional water bodies and consubstantiate evidences of G. catenatum as one of the main sources of BMAA in these ecosystems. PMID:24747603

  15. Thirty years - Alexandrium fundyense cyst, bloom dynamics and shellfish toxicity in the Bay of Fundy, eastern Canada

    NASA Astrophysics Data System (ADS)

    Martin, Jennifer L.; LeGresley, Murielle M.; Hanke, Alex R.

    2014-05-01

    Sediment and water samples were collected for Alexandrium fundyense spatial and temporal distribution and abundance at more than 120 locations throughout the Bay of Fundy during the summers and winters of 1980-1984. These broad surveys have been repeated at various times through the past 30 years, with more regular sampling since 2004. In addition, A. fundyense abundance has been monitored at several locations within the Bay of Fundy at weekly intervals from April to November and monthly during the remaining months since 1988. Paralytic Shellfish Poisoning (PSP) toxins in shellfish (notably Mya arenaria) have also been monitored at multiple locations in the Bay of Fundy since 1943. The datasets were examined to determine relationships and roles between overwintering resting cysts, bloom initiation, bloom decline, motile cell dispersal and A. fundyense motile populations and resulting shellfish toxicity since 1980. Cysts are widely dispersed throughout the Bay of Fundy in the offshore, inshore and intertidal zones with the largest deposits located in the offshore in silt/clay sediments to the east and north of Grand Manan Island at depths of 60-180 m. Results show that there is a constant stable source of cysts in the Bay of Fundy with highest concentrations of cysts (9780 cysts cm-3) observed in 2010 and highest concentrations of A. fundyense motile cells (18×106 cells L-1) observed in 1980. Interannual changes in abundance in A. fundyense populations, resting cysts and the temporal trends in M. arenaria toxicity are discussed. Results show that there was no relationship between the abundance of overwintering cysts and the magnitude of A. fundyense blooms. The offshore seed beds appear to be relatively constant in cyst density among most years and serve as an important source for the motile cells that lead to initiation of major blooms and resulting shellfish toxicity throughout the Bay of Fundy.

  16. Feasibility studies into the production of gamma-irradiated oyster tissue reference materials for paralytic shellfish poisoning toxins.

    PubMed

    Turner, Andrew D; Lewis, Adam M; Hatfield, Robert G; Powell, Andy L; Higman, Wendy A

    2013-09-01

    A study was conducted to assess the feasibility for the production of sterile, stable and homogenous shellfish reference materials containing known concentrations of paralytic shellfish poisoning (PSP) toxins. Pacific oysters were contaminated with toxins following mass culturing of toxic algae and shellfish feeding experiments. Live oysters were shucked and tissues homogenised, before measuring into multiple aliquots, with one batch subjected to gamma irradiation treatment and the other remaining untreated. The homogeneity of both batches of samples was assessed using a pre-column oxidation liquid chromatography with fluorescence detection (Pre-COX LC-FLD) method and shown to be within the limits of normal within-batch repeatability. A twelve-month stability experiment was conducted for both untreated and gamma irradiated batches, specifically examining the effects of long term storage at -20 °C, +4 °C and +40 °C. Results indicated mostly good stability of PSP toxins in both materials when stored frozen at -20 °C, but with the instability of GTX2&3 concentrations in the untreated tissues eliminated in the irradiated tissues. Analysis using a post-column oxidation (PCOX) LC-FLD method also showed epimerisation in both GTX1&4 and GTX2&3 epimeric pairs in untreated samples after only 6 months frozen storage. This issue was not present in the tissues irradiated before long term storage. Biological activity testing confirmed the absence of bacteria in the irradiated samples throughout the 12 month study period. With such results there was clear evidence for the potential of increasing the scale of the mass culturing and shellfish feeding for the production of large batches of tissue suitable for the preparation of a certified matrix reference material. Overall results demonstrated the feasibility for production of oyster reference materials for PSTs, with evidence for prolonged stability following gamma irradiation treatment and storage at -20 °C. PMID

  17. Trading green backs for green crabs: evaluating the commercial shellfish harvest at risk from European green crab invasion.

    PubMed

    Mach, Megan E; Chan, Kai Ma

    2013-01-01

    Nonnative species pose a threat to native biodiversity and can have immense impacts on biological communities, altering the function of ecosystems. How much value is at risk from high-impact invasive species, and which parameters determine variation in that value, constitutes critical knowledge for directing both management and research, but it is rarely available. We evaluated the value of the commercial shellfish harvest that is at risk in nearshore ecosystems of Puget Sound, Washington State, USA, from the invasive European green crab, Carcinus maenas. We assessed this value using a simple static ecological model combined with an economic model using data from Puget Sound's shellfish harvest and revenue and the relationship between C. maenas abundance and the consumption rate of shellfish. The model incorporates a range in C. maenas diet preference, calories consumed per year, and crab densities. C. maenas is likely to prey on commercially harvested hardshell clams, oysters, and mussels, which would likely reduce additional revenue from processing and distribution, and the number of jobs associated with these fisheries. The model results suggest possible revenue losses of these shellfish ranging from $1.03-23.8 million USD year (-1) (2.8-64% losses), with additional processing and distribution losses up to $17.6 million USD and 442 job positions each year associated with a range of plausible parameter values. The broad range of values reflects the uncertainty in key factors underlying impacts, factors that are highly variable across invaded regions and so not knowable a priori. However, future research evaluating species invasions can reduce the uncertainty of impacts by characterizing several key parameters: density of individuals, number of arrivals, predation and competition interactions, and economic impacts. This study therefore provides direction for research to inform more accurate estimates of value-at-risk, and suggests substantial motivation for

  18. Trading green backs for green crabs: evaluating the commercial shellfish harvest at risk from European green crab invasion

    PubMed Central

    Mach, Megan E; Chan, Kai MA

    2014-01-01

    Nonnative species pose a threat to native biodiversity and can have immense impacts on biological communities, altering the function of ecosystems. How much value is at risk from high-impact invasive species, and which parameters determine variation in that value, constitutes critical knowledge for directing both management and research, but it is rarely available. We evaluated the value of the commercial shellfish harvest that is at risk in nearshore ecosystems of Puget Sound, Washington State, USA, from the invasive European green crab, Carcinus maenas. We assessed this value using a simple static ecological model combined with an economic model using data from Puget Sound’s shellfish harvest and revenue and the relationship between C. maenas abundance and the consumption rate of shellfish. The model incorporates a range in C. maenas diet preference, calories consumed per year, and crab densities. C. maenas is likely to prey on commercially harvested hardshell clams, oysters, and mussels, which would likely reduce additional revenue from processing and distribution, and the number of jobs associated with these fisheries. The model results suggest possible revenue losses of these shellfish ranging from $1.03-23.8 million USD year -1 (2.8-64% losses), with additional processing and distribution losses up to $17.6 million USD and 442 job positions each year associated with a range of plausible parameter values. The broad range of values reflects the uncertainty in key factors underlying impacts, factors that are highly variable across invaded regions and so not knowable a priori. However, future research evaluating species invasions can reduce the uncertainty of impacts by characterizing several key parameters: density of individuals, number of arrivals, predation and competition interactions, and economic impacts. This study therefore provides direction for research to inform more accurate estimates of value-at-risk, and suggests substantial motivation for

  19. Application of rapid test kits for the determination of Diarrhetic Shellfish Poisoning (DSP) toxins in bivalve molluscs from Great Britain.

    PubMed

    Johnson, Sarah; Harrison, Keith; Turner, Andrew D

    2016-03-01

    Four commercial rapid screening methods for Diarrhetic Shellfish Poisoning were applied to the analysis of naturally contaminated shellfish samples from GB. The performance of each kit was assessed through comparison with the reference LC-MS/MS method on a range of both positive and negative bivalve mollusc samples. A quantitative PP2A protein phosphatase assay was the only assay to show the complete absence of false negative results. It showed a fair correlation with LC-MS/MS but with an overall overestimation of sample toxicity together with some indications of interference from sample matrix, most notably within oyster species. A quantitative competitive ELISA also gave a fair correlation with LC-MS/MS, with no evidence of toxicity overestimation and with a good response to samples containing little or no DST's, although one false negative was recorded. The two qualitative lateral flow assays both provided a high percentage agreement with the LC-MS/MS results and there were no indications of false positive results, although both kits also returned one false negative result. The false negative results returned by the three assays were all associated with samples containing high proportions of DTX2, a toxin which occurs commonly in UK shellfish. The scanners provided with both lateral flow assays were easy to use and the provision of numerical results enables a semi-quantitative assessment of toxicities which would significantly benefit the end user. Whilst key differences exist between the proposed assays they are all rapid, do not require expensive equipment and the work here has provided some evidence for suitability for indicative testing for some species of bivalve shellfish from GB. Further work is required however using a larger number of test kit batches on a greater number of samples, particularly for those containing high proportions of DTX2. PMID:26792713

  20. Characterisation of the paralytic shellfish toxin biosynthesis gene clusters in Anabaena circinalis AWQC131C and Aphanizomenon sp. NH-5

    PubMed Central

    Mihali, Troco K; Kellmann, Ralf; Neilan, Brett A

    2009-01-01

    Background Saxitoxin and its analogues collectively known as the paralytic shellfish toxins (PSTs) are neurotoxic alkaloids and are the cause of the syndrome named paralytic shellfish poisoning. PSTs are produced by a unique biosynthetic pathway, which involves reactions that are rare in microbial metabolic pathways. Nevertheless, distantly related organisms such as dinoflagellates and cyanobacteria appear to produce these toxins using the same pathway. Hypothesised explanations for such an unusual phylogenetic distribution of this shared uncommon metabolic pathway, include a polyphyletic origin, an involvement of symbiotic bacteria, and horizontal gene transfer. Results We describe the identification, annotation and bioinformatic characterisation of the putative paralytic shellfish toxin biosynthesis clusters in an Australian isolate of Anabaena circinalis and an American isolate of Aphanizomenon sp., both members of the Nostocales. These putative PST gene clusters span approximately 28 kb and contain genes coding for the biosynthesis and export of the toxin. A putative insertion/excision site in the Australian Anabaena circinalis AWQC131C was identified, and the organization and evolution of the gene clusters are discussed. A biosynthetic pathway leading to the formation of saxitoxin and its analogues in these organisms is proposed. Conclusion The PST biosynthesis gene cluster presents a mosaic structure, whereby genes have apparently transposed in segments of varying size, resulting in different gene arrangements in all three sxt clusters sequenced so far. The gene cluster organizational structure and sequence similarity seems to reflect the phylogeny of the producer organisms, indicating that the gene clusters have an ancient origin, or that their lateral transfer was also an ancient event. The knowledge we gain from the characterisation of the PST biosynthesis gene clusters, including the identity and sequence of the genes involved in the biosynthesis, may

  1. Water pollution: Uptake of heavy metals by shellfish and marine plants. (Latest citations from Oceanic Abstracts). Published Search

    SciTech Connect

    Not Available

    1992-07-01

    The bibliography contains citations concerning heavy metal contamination of shellfish and marine plants. Toxicity levels and the long term effects on the ecology of the marine environment are discussed. The growth rate of marine life as a function of metal concentration and the long term effects on the food chain are also considered. (Contains 250 citations and includes a subject term index and title list.)

  2. Application of rapid test kits for the determination of Amnesic Shellfish Poisoning in bivalve molluscs from Great Britain.

    PubMed

    Johnson, Sarah; Harrison, Keith; Turner, Andrew D

    2016-07-01

    Five commercial rapid screening methods for Amnesic Shellfish Poisoning were assessed for the analysis of naturally contaminated bivalve mollusc samples from GB. A range of shellfish species including mussels, scallops, clams, oysters and cockles, both positive and negative for domoic acid were assessed, with kit performance measured through comparison with the reference HPLC-UV method. Two lateral flow immunoassays manufactured by Neogen and Scotia Rapid Testing Ltd, were both found to provide a simple and accurate qualitative detection of ASP in shellfish. No false negative or false positive results were returned by either assay. The Scotia method showed the additional advantage of providing a numerical result which was found to correlate well with domoic acid concentration, thus providing a useful additional semi-quantitative aspect to the testing. Three ELISA kits, supplied by Beacon, Biosense and Bioo Scientific were all found to provide a good qualitative indication for the presence of domoic acid. Quantitative results varied between the three assays. The Beacon assay was the only kit to return no false negative results for samples containing domoic acid at concentrations above the maximum permitted regulatory limit of 20 mg/kg, but with, on average, a slight over-estimation of toxin concentrations. Both the Biosense and, more notably, the Bioo Scientific kits tended to under-estimate toxin levels, with both assays also returning false negative results. All methods were relatively straightforward to use, with the lateral flow assays in particular providing a simple and rapid methodology suited to those with no access to laboratory equipment. Whilst the data has provided some evidence for suitability for indicative testing for some species of bivalve shellfish from GB, further work would ideally be required using a larger number of test kit batches on a greater number of samples for any method being utilised safely for routine testing. PMID:27070387

  3. Characterization of organochlorine pesticides, brominated flame retardants and dioxin-like compounds in shellfish and eel from Fiji.

    PubMed

    Lal, Vincent; Bridgen, Phil; Votadroka, Waisea; Raju, Rupantri; Aalbersberg, William

    2014-09-01

    This article gives an overview of a range of persistent organic pollutant chemical levels in shellfish (Batissa violacea and Anadara antiquata) species and eel (Gymnothorax flavimarginatus) from Fiji. As there is limited data in published literature to date, this paper reports first data on a range of persistent organic pollutants and highlights the more prominent POP chemicals present in marine biota in Fiji. A significant number of POP chemicals were detected (e.g. 17 PCDD/PCDF, 12dl-PCBs, organochlorine pesticides and brominated flame retardants), the concentrations found were generally low (e.g. parts per billion level). The low levels of contamination are indicative of a low input from long range and short-range transport as well as few local point sources. Also concentrations of POPs in eel and shellfish from Fiji are low in comparison to wild species in other regions and are within acceptable limits for POP chemicals in fish and fishery products set by the European Union. It describes also results of early studies on basic POPs levels in shellfish in several Pacific Island Countries, which generally show relatively low levels. PMID:24568747

  4. Nutrients and Chemical Pollutants in Fish and Shellfish. Balancing Health Benefits and Risks of Regular Fish Consumption.

    PubMed

    Domingo, José L

    2016-01-01

    Dietary patterns and lifestyle factors are clearly associated with at least five of the ten leading causes of death, including coronary heart disease, certain types of cancer, stroke, non-insulin insulin-dependent diabetes mellitus, and atherosclerosis. Concerning specifically fish and seafood consumption, its beneficial health effects in humans are clearly supported by an important number of studies performed in the last 30 years. These studies have repeatedly linked fish consumption, especially those species whose contents in omega-3 fatty acids are high, with healthier hearts in the aging population. The nutritional benefits of fish and seafood are also due to the content of high-quality protein, vitamins, as well as other essential nutrients. However, a number of studies, particularly investigations performed in recent years, have shown that the unavoidable presence of environmental contaminants in fish and shellfish can also mean a certain risk for the health of some consumers. While prestigious international associations as the American Heart Association have recommended eating fish at least two times (two servings a week), based on our own experimental results, as well as in results from other laboratories, we cannot be in total agreement with that recommendation. Although a regular consumption of most fish and shellfish species should not mean adverse health effects for the consumers, the specific fish and shellfish species consumed, the frequency of consumption, as well as the meal size, are essential issues for adequately balancing the health benefits and risks of regular fish consumption. PMID:25486051

  5. Determination of toxic elements (mercury, cadmium, lead, tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers.

    PubMed

    Olmedo, P; Pla, A; Hernández, A F; Barbier, F; Ayouni, L; Gil, F

    2013-09-01

    Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead). PMID:23792415

  6. Seasonal abundance and composition of finfish and shellfish seeds inmangroves of Gangolli estuary, off south-west coast of India.

    PubMed

    Rajesh, K M; Thomas, Sujitha; Dineshbabu, A R; PrathibhaRohit; Sridhara, B; Nataraja, G D

    2015-11-01

    The composition and seasonal abundance of the fin and shellfish seeds in mangrove areas of Gangoli estuary were studied for one year from January to December, 2013. Monthly day time sampling was conducted with a rectangular dragnet of 75 m2 length having 5 mm mesh size. The mean monthly density was highest in January (Avg. of 12,996/haul) and lowest during May (Avg. of 859/haul). Thirty species of fish, four species of shrimps and two species of crabs belonging to 26 families were recorded during the study. Ambasis sp., Feneropenaeus indicus, Etroplus suratensis,Leognathus sp., Liza sp., Stolephorus vaganensis, Hemiramphus sp., Terapon sp. and Gerres sp. were the most abundant species/taxa. A total of 10 commercially important species comprising F. indicus, Etroplus suratensis, Liza sp., Gerres sp.,Siganus sp., Lutjanus russei, Macrobrachium rosenbergii, Lutjanus argentimaculatus, Sillago sp. and Penaeus monodon constituted 8.5% (April, 2013) to 93.7% (October, 2013) with an average of 37.2% of the total fish and shellfish seeds. Higher Species diversity (H') and Species richness (D) was recorded during January. The result of the present investigation gives an insight of the abundance and seasonality of commercially important fish and shellfish seeds, which may facilitate the brackishwater fish farmers to exploitthe seeds more pragmatically for their culture practice. PMID:26688975

  7. A comparative study for PSP toxins quantification by using MBA and HPLC official methods in shellfish.

    PubMed

    Ben-Gigirey, B; Rodríguez-Velasco, M L; Otero, A; Vieites, J M; Cabado, A G

    2012-10-01

    Commission Regulation (EC) N° 2074/2005 recognises the biological method as the reference method for Paralytic Shellfish Poisoning (PSP) toxins detection in molluscs. It was amended by Commission Regulation (EC) N° 1664/2006 that accepted the so-called Lawrence method as an alternative to the reference method. The goal of this study was to compare AOAC Official Methods of Analysis 959.08 (Biological method) and 2005.06 (Prechromatographic Oxidation and Liquid Chromatography with fluorescence detection) in samples with different toxin profiles. The influence of extraction solvent in the total samples toxicity was also evaluated. A total of 40 samples including mussels, clams, scallops, razor-clams, cockles, oysters and barnacles were analysed by both official methods. Samples were selected with Alexandrium and Gymnodinium toxic profiles, from different origin and including several presentations: fresh, frozen, canned and boiled. Acetic and hydrochloric acid extractions were performed in all samples and the extracts were simultaneously analysed by both methods. Most samples were naturally contaminated and two samples were spiked. Comparison of both official methods, mouse bioassay (MBA) with HCl extraction and Liquid Chromatography with fluorescence detection (HPLC-FLD) with acetic acid extraction, led to an 85% of consistent results regarding compliance with legal limit, including samples below and above it. The linear correlation coefficient was r² = 0.69 and the paired t test (two tails, α = 0.05) indicated that there were not significant differences among both sets of data. Nevertheless, toxicity differences were found in several samples. In 15 out of 18 shellfish with a Gymnodinium toxic profile, higher toxicity levels were obtained by MBA. This fact was more evident in 7 samples, partially related to the lack of standards and the impossibility of analysing dc-NEO, C1, 2 and GTX6 at the beginning of the study. However, other factors concerning the extraction

  8. Assessment and Molecular Characterization of Human Intestinal Parasites in Bivalves from Orchard Beach, NY, USA

    PubMed Central

    Tei, Freda F.; Kowalyk, Steven; Reid, Jhenelle A.; Presta, Matthew A.; Yesudas, Rekha; Mayer, D.C. Ghislaine

    2016-01-01

    Bivalves have been shown to be carriers of the human intestinal parasites Cryptosporidium parvum and Toxoplasma gondii. The goal of this study is to determine the prevalence of protozoan parasites in mollusks of New York City using a polymerase chain reaction (PCR)-based assay. Four species of mollusks, Mya arenaria, Geukensia demissa, Crassostrea virginica, and Mytilis edulis, were collected from Orchard Beach, NY in the fall of 2014, totaling 159 specimens. Each individual mollusk was dissected to harvest the digestive gland, the mantle, the gills, the foot and the siphon. The tissues were assayed for the presence of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii DNA by using primers that target parasite-specific genes. C. parvum was found at a prevalence of 50%, 11.3%, and 1%, respectively, in Mya arenaria, G. demissa, and Mytilis edulis. C. parvum DNA was detected in all the tissues of these bivalve species, except the gills. Furthermore, G. lamblia was detected in Mya arenaria, G. demissa, Crassostrea virginica and Mytilis edulis at a prevalence of 37.5%, 4.5%, 60%, and 20.6%, respectively, while T. gondii DNA was not detected. PMID:27043590

  9. Assessment and Molecular Characterization of Human Intestinal Parasites in Bivalves from Orchard Beach, NY, USA.

    PubMed

    Tei, Freda F; Kowalyk, Steven; Reid, Jhenelle A; Presta, Matthew A; Yesudas, Rekha; Mayer, D C Ghislaine

    2016-01-01

    Bivalves have been shown to be carriers of the human intestinal parasites Cryptosporidium parvum and Toxoplasma gondii. The goal of this study is to determine the prevalence of protozoan parasites in mollusks of New York City using a polymerase chain reaction (PCR)-based assay. Four species of mollusks, Mya arenaria, Geukensia demissa, Crassostrea virginica, and Mytilis edulis, were collected from Orchard Beach, NY in the fall of 2014, totaling 159 specimens. Each individual mollusk was dissected to harvest the digestive gland, the mantle, the gills, the foot and the siphon. The tissues were assayed for the presence of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii DNA by using primers that target parasite-specific genes. C. parvum was found at a prevalence of 50%, 11.3%, and 1%, respectively, in Mya arenaria, G. demissa, and Mytilis edulis. C. parvum DNA was detected in all the tissues of these bivalve species, except the gills. Furthermore, G. lamblia was detected in Mya arenaria, G. demissa, Crassostrea virginica and Mytilis edulis at a prevalence of 37.5%, 4.5%, 60%, and 20.6%, respectively, while T. gondii DNA was not detected. PMID:27043590

  10. Limited selection of sodium channel blocking toxin-producing bacteria from paralytic shellfish toxin-contaminated mussels (Aulacomya ater).

    PubMed

    Vásquez, Mónica; Grüttner, Carol; Möeller, Blanca; Moore, Edward R B

    2002-01-01

    Paralytic shellfish toxins (PSTs) are sodium channel blocking (SCB) toxins, produced by cyanobacteria, as well as by marine dinoflagellates and their associated bacteria, and cause serious health and economic concern worldwide. In a previous study, approximately 70% of the bacteria enriched from PST-contaminated shellfish tissue and isolated on marine agar medium were observed to produce SCB toxins. In the study reported here, the high percentage of cultivable toxigenic bacteria is demonstrated to be obtained through a marked selection on marine agar medium. The cultivable as well as the total bacterial diversity associated with PST-contaminated shellfish collected from the Magallanes region in the south of Chile has been analysed. Approximately 80% of bacterial isolates, analysed by restriction analysis of PCR amplified ribosomal DNA (i.e., ARDRA fingerprinting), were limited to only two genotypic OTUs (operational taxonomic unit). Sequence determination and analysis of the 16S rDNA from representative isolates of both OTUs established them to be closely related to species of the Psychrobacter genus of the gamma-subclass of the Proteobacteria. The total bacterial diversity in the shellfish was further analysed, using a cultivation-independent strategy of extraction of total DNA from contaminated tissue, PCR-amplification of bacterial 16S rRNA genes, cloning of the PCR products and analysis of the cloned 16S rDNA sequence types by fingerprinting and sequencing. Only 2% of the cloned sequence types corresponded to species of the Psychrobacter genus. The 16S rDNA sequence types detected clustered with species of the y-Proteobacteria subclass, the Cytophaga-Flexibacter-Bacteroides (CFB), the Fusobacteria and the Firmicutes phyla. The level of diversity observed within the libraries of cloned 16S rDNA was markedly greater than that observed among isolates obtained through marine agar enrichment cultures from the same shellfish tissue. Additionally the predominant

  11. Predator lipids induce paralytic shellfish toxins in bloom-forming algae

    PubMed Central

    Selander, Erik; Kubanek, Julia; Hamberg, Mats; Andersson, Mats X.; Cervin, Gunnar; Pavia, Henrik

    2015-01-01

    Interactions among microscopic planktonic organisms underpin the functioning of open ocean ecosystems. With few exceptions, these organisms lack advanced eyes and thus rely largely on chemical sensing to perceive their surroundings. However, few of the signaling molecules involved in interactions among marine plankton have been identified. We report a group of eight small molecules released by copepods, the most abundant zooplankton in the sea, which play a central role in food webs and biogeochemical cycles. The compounds, named copepodamides, are polar lipids connecting taurine via an amide to isoprenoid fatty acid conjugate of varying composition. The bloom-forming dinoflagellate Alexandrium minutum responds to pico- to nanomolar concentrations of copepodamides with up to a 20-fold increase in production of paralytic shellfish toxins. Different copepod species exude distinct copepodamide blends that contribute to the species-specific defensive responses observed in phytoplankton. The signaling system described here has far reaching implications for marine ecosystems by redirecting grazing pressure and facilitating the formation of large scale harmful algal blooms. PMID:25918403

  12. Experimental studies of succession and stability in rocky intertidal communities subject to artisanal shellfish gathering

    NASA Astrophysics Data System (ADS)

    Dye, A. H.

    Rocky-shore communities on the east coast of southern Africa are subject to intense shellfish exploitation by coastal people. Large-scale removal of sessile species, such as the mussel Perna perna, creates areas of bare rock, providing space for colonization. Rates of recolonization of experimentally-cleared areas in both protected and exploited sites were found to be variable. There was as much as a two-year delay before sessile macro-organisms reappeared, and the course of subsequent succession depended on the nature of the initial colonists. Large spatial and temporal variations in species diversity and richness were observed where it appeared that emergent communities were less stable than adjacent controls. After eight to nine years, few of the cleared areas have developed communities similar to the original or to controls. These results are compared with those of a controlled exploitation experiment conducted in a nature reserve. Similar results were obtained despite the fact that exploitation was more selective for target species and did not involve total clearance. The long-term effects of human exploitation involve shifts in community structure towards earlier successional stages which may persist for long periods of time. Consequently, management options such as rotational cropping may be inappropriate in such a system.

  13. Paralytic shellfish toxins, including deoxydecarbamoyl-STX, in wild-caught Tasmanian abalone (Haliotis rubra).

    PubMed

    Harwood, D Tim; Selwood, Andrew I; van Ginkel, Roel; Waugh, Craig; McNabb, Paul S; Munday, Rex; Hay, Brenda; Thomas, Krista; Quilliam, Michael A; Malhi, Navreet; Dowsett, Natalie; McLeod, Catherine

    2014-11-01

    For the first time wild-caught Tasmanian abalone, Haliotis rubra, have been reported to contain paralytic shellfish toxins (PSTs). This observation followed blooms of the toxic dinoflagellate Gymnodinium catenatum. No illnesses were reported, but harvesting restrictions were enforced in commercial areas. Abalone were assayed using HPLC-FLD methodology based on AOAC official method 2005.06. An uncommon congener, deoxydecarbamoyl-STX (doSTX), was observed in addition to regulated PSTs as unassigned chromatographic peaks. A quantitative reference material was prepared from contaminated Tasmanian abalone viscera and ampouled at 54.2 μmol/L. The LD50 of doSTX via intraperitoneal injection was 1069 nmol/kg (95% confidence limits 983-1100 nmol/kg), indicating it is nearly 40 times less toxic than STX. A toxicity equivalence factor of 0.042 was generated using the mouse bioassay. Levels of PSTs varied among individuals from the same site, although the toxin profile remained relatively consistent. In the foot tissue, STX, decarbamoyl-STX and doSTX were identified. On a molar basis doSTX was the dominant congener in both foot and viscera samples. The viscera toxin profile was more complex, with other less toxic PST congeners observed and was similar to mussels from the same site. This finding implicates localised dinoflagellate blooms as the PST source in Tasmanian abalone. PMID:25157803

  14. Mining the transcriptomes of four commercially important shellfish species for single nucleotide polymorphisms within biomineralization genes.

    PubMed

    Vendrami, David L J; Shah, Abhijeet; Telesca, Luca; Hoffman, Joseph I

    2016-06-01

    Transcriptional profiling not only provides insights into patterns of gene expression, but also generates sequences that can be mined for molecular markers, which in turn can be used for population genetic studies. As part of a large-scale effort to better understand how commercially important European shellfish species may respond to ocean acidification, we therefore mined the transcriptomes of four species (the Pacific oyster Crassostrea gigas, the blue mussel Mytilus edulis, the great scallop Pecten maximus and the blunt gaper Mya truncata) for single nucleotide polymorphisms (SNPs). Illumina data for C. gigas, M. edulis and P. maximus and 454 data for M. truncata were interrogated using GATK and SWAP454 respectively to identify between 8267 and 47,159 high quality SNPs per species (total=121,053 SNPs residing within 34,716 different contigs). We then annotated the transcripts containing SNPs to reveal homology to diverse genes. Finally, as oceanic pH affects the ability of organisms to incorporate calcium carbonate, we honed in on genes implicated in the biomineralization process to identify a total of 1899 SNPs in 157 genes. These provide good candidates for biomarkers with which to study patterns of selection in natural or experimental populations. PMID:26806806

  15. In vitro bioaccessibility of the marine biotoxin okadaic acid in shellfish.

    PubMed

    Braga, Ana C; Alves, Ricardo N; Maulvault, Ana L; Barbosa, Vera; Marques, António; Costa, Pedro R

    2016-03-01

    Okadaic acid (OA) and their derivatives are marine toxins responsible for the human diarrhetic shellfish poisoning (DSP). To date the amount of toxins ingested in food has been considered equal to the amount of toxins available for uptake by the human body. In this study, the OA fraction released from the food matrix into the digestive fluids (bioaccessibility) was assessed using a static in vitro digestion model. Naturally contaminated mussels (Mytilus galloprovincialis) and donax clams (Donax sp.), collected from the Portuguese coast, containing OA and dinophysistoxin-3 (DTX3) were used in this study. Bioaccessibility of OA total content was 88% and 75% in mussels and donax clams, respectively. Conversion of DTX3 into its parent compound was verified during the simulated digestive process and no degradation of these toxins was found during the process. This is the first study assessing the bioaccessibility of OA-group toxins in naturally contaminated seafood. This study provides relevant new data that can improve and lead to more accurate food safety risk assessment studies concerning these toxins. PMID:26783635

  16. Role of shellfish hatchery as a reservoir of antimicrobial resistant bacteria.

    PubMed

    Miranda, Claudio D; Rojas, Rodrigo; Garrido, Marcela; Geisse, Julieta; González, Gerardo

    2013-09-15

    The main aim of this study was to determine the occurrence of resistant bacteria in florfenicol-treated and untreated scallop larval cultures from a commercial hatchery and to characterize some selected florfenicol-resistant strains. Larval cultures from untreated and treated rearing tanks exhibited percentages of copiotrophic bacteria resistant to florfenicol ranging from 0.03% to 10.67% and 0.49-18.34%, respectively, whereas florfenicol resistance among oligotrophic bacteria varied from 1.44% to 35.50% and 3.62-95.71%, from untreated and treated larvae, respectively. Florfenicol resistant microbiota from reared scallop larvae mainly belonged to the Pseudomonas and Pseudoalteromonas genus and were mainly resistant to florfenicol, chloramphenicol, streptomycin and co-trimoxazole. This is the first study reporting antimicrobial resistant bacteria associated to a shellfish hatchery and the results suggest that a continuous surveillance of antimicrobial resistance even in absence of antibacterial therapy is urgently required to evaluate potential undesirable consequences on the surrounding environments. PMID:23880028

  17. Predator lipids induce paralytic shellfish toxins in bloom-forming algae.

    PubMed

    Selander, Erik; Kubanek, Julia; Hamberg, Mats; Andersson, Mats X; Cervin, Gunnar; Pavia, Henrik

    2015-05-19

    Interactions among microscopic planktonic organisms underpin the functioning of open ocean ecosystems. With few exceptions, these organisms lack advanced eyes and thus rely largely on chemical sensing to perceive their surroundings. However, few of the signaling molecules involved in interactions among marine plankton have been identified. We report a group of eight small molecules released by copepods, the most abundant zooplankton in the sea, which play a central role in food webs and biogeochemical cycles. The compounds, named copepodamides, are polar lipids connecting taurine via an amide to isoprenoid fatty acid conjugate of varying composition. The bloom-forming dinoflagellate Alexandrium minutum responds to pico- to nanomolar concentrations of copepodamides with up to a 20-fold increase in production of paralytic shellfish toxins. Different copepod species exude distinct copepodamide blends that contribute to the species-specific defensive responses observed in phytoplankton. The signaling system described here has far reaching implications for marine ecosystems by redirecting grazing pressure and facilitating the formation of large scale harmful algal blooms. PMID:25918403

  18. DDT contamination in selected estuarine and coastal marine finfish and shellfish of New Jersey.

    PubMed

    Kennish, M J; Ruppel, B E

    1996-08-01

    Analysis of DDT contamination in selected finfish and shellfish species from estuarine and coastal marine waters of New Jersey (USA) reveals consistently highest organochlorine pesticide levels in samples from the north and northeast regions of the state. The mean concentrations of DDT and its metabolites, DDE and DDD, in bluefish, striped bass, weakfish, and blue crabs collected at 27 stations throughout the state between 1988 and 1991 ranged from <25 to >300 microg/kg wet weight (wet wt). Gas chromatographic analysis of 175 tissue samples from these four species showed that the highest levels of DDTs (DDT plus DDE and DDD), exceeding 300 microg/kg wet wt, occurred in blue crabs (hepatopancreas) from the Hudson-Newark-Raritan Bay complex in the northeast region. Lower mean concentrations of DDTs (<200 microg/kg wet wt) were recorded in tissue samples of these species from all other regions of the state. The lowest levels of DDT contamination (mean <110 microg/kg wet wt) were found in samples from the south coast region. The greatest impact of DDT contamination is nearby metropolitan areas of the state, although the total concentrations of DDT in tissue samples from these areas are far less than the U.S. Food and Drug Administration action level of 5,000 microg/kg wet wt for this contaminant. PMID:8781078

  19. Sea otter mortality in fish and shellfish traps: Estimating potential impacts and exploring possible solutions

    USGS Publications Warehouse

    Hatfield, B.B.; Ames, J.A.; Estes, J.A.; Tinker, M.T.; Johnson, A.B.; Staedler, M.M.; Harris, M.D.

    2011-01-01

    Sea otters Enhydra lutris can be bycaught and drowned in fishing pots and traps, which may pose a threat to the welfare of otter populations. We explored this potential problem and its solutions using a wide variety of analyses. We exposed live California (USA) sea otters to finfish traps, lobster traps, and mock Dungeness crab traps in captive trials and found that the animals attempted to enter the circular and rectangular fyke openings, with some becoming entrapped. Using both live and dead sea otters, we found that a 3 ?? 9 inch (7.6 ?? 22.9 cm) fyke opening (1 inch narrower than the 4 ?? 9 inch [10.2 ?? 22.9 cm] openings currently used in California's commercial Dungeness crab fishery) would exclude most free-living (i.e. weaned from their mothers) otters while permitting the undiminished capture of crabs. Observer programs do not currently exist in California for these fisheries, so we calculated the effort required by an observer program to document sea otter bycatch over a range of hypothetical levels and evaluated the impact of those mortality rates on population growth. These analyses demonstrate that significant mortality from bycatch might easily go undetected, even with seemingly high levels of observer effort. As sea otters reoccupy portions of their former habitat in California, co-occurrence with finfish and shellfish traps with relatively large fyke openings will increase. ?? Inter-Research 2011.

  20. Depuration of shellfish by irradiation: Final technical report, October 1, 1987--March 31, 1989

    SciTech Connect

    Beghian, L.E.; Mallett, J.C.

    1989-01-01

    Studies by the University of Lowell Radiation Laboratory and the US National Marine Fisheries Service N.E. Laboratory in Gloucester, MA on softshelled clams (Mya arenaria) demonstrated the effectiveness of low to medium doses of Cobalt 60 source gamma irradiation in the inactivation of Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Streptococcus faecalis. Post-irradiation survival and organoleptic studies when extended to hardshelled clams (Mercinaria mercenaria) and American oysters (Crassostrea virginica) showed no significant decline in consumer qualities or 6 day post irradiation survival in oysters at doses of up to 3.0 kGy. The capacities of the American oyster to sustain relatively high doses of gamma irradiation were demonstrated by 6 day post-exposure survivorship values of greater than 90% for samples receiving 3.0, 5.0 and 7.0 kGy. Initial studies of inactivation of Polio I virus and a simian rotavirus (SA-11) was conducted in both hardshelled clams and oysters. Of greatest interest was the behavior of Hepatitis A virus (HAV), in live, irradiated shellfish. The average log decrement value for HAV in oysters was calculated at 2.0 kGy. From these data it appears that doses of up to 2 kGy can be applied to: reduce or eliminate bacterial pathogens, reduce the infectivity of human viral pathogens by one or more orders of magnitude, and preserve market qualities of longevity, appearance, odor, taste and texture. 23 refs., 11 figs., 3 tabs.

  1. Shellfish depuration by gamma irradiation: Final report for the period October 1, 1985-September 30, 1986

    SciTech Connect

    Beghian, L.; Melnick, J.

    1986-11-01

    Irradiation of live bivalve molluscs is a promising new technique to reduce the public health threats of viral and bacterial pathogens in the consumption of raw shellfish. In studies conducted within the past year, live hardshelled clams and oysters were innoculated with Simian Rotavirus SA-11, Poliovirus I, and Hepatitis-A virus and treated with gamma ray ionizing radiation from University of Lowell/DOE 800,000 Curie /sup 60/Co source over a dose range of 0.5--10 kiloGray (50--1000 kilorad) to determine the effectiveness of the process in eliminating viral activity and thus easing the potential viral health threats associated with uncooked bivalves. Two viral strains, SA-11 and Poliovirus I, were employed as models to perfect laboratory technique and to estimate the most appropriate range of dose exposures necessary for optimal inactivation of the infectious pathogen, Hepatitis A. Post-irradiation survivorship of the oysters and quahogs was assessed over a range of exposures, and showed an exceptionally high degree of radioresistance for these molluscan species. 7 refs., 7 figs., 14 tabs.

  2. Predictive mechanistic bioenergetics to model habitat suitability of shellfish culture in coastal lakes

    NASA Astrophysics Data System (ADS)

    Rinaldi, A.; Montalto, V.; Manganaro, A.; Mazzola, A.; Mirto, S.; Sanfilippo, M.; Sarà, G.

    2014-05-01

    Quantitative tools based on mechanistic modelling of functional traits able to enhance the sustainability of aquaculture and most other human activities (i.e. reducing the likelihood of detrimental impacts optimising productions), are especially important factors in the decision to site aquaculture facilities in coastal lakes, ponds and lagoons and, in the case of detrimental impact, to adopt mitigation measures. We tested the ability of mechanistic functional trait based models to predict life history traits of cultivable shellfish in shallow coastal lakes. Dynamic Energy Budget (DEB) models were run to generate spatially explicit predictions of Mytilus galloprovincialis life history (LH) traits (e.g. body size and fecundity). Using fortnightly data of food supply and hourly data of body temperatures, and exploiting the power of mechanistic rules, we estimated the amount of faeces ejected by a fixed quantity of organisms cultivated in two shallow Southern Mediterranean (Sicily) lakes. These differed in terms of temperature and food density, implying large differences in life history traits of mussels in the two study areas. This information could help facilitate the selection of sites where environmental conditions are more suitable for aquaculture and contextually compatible with sustainability. The validation exercise obtained by comparing the predicted and observed data was nearly consistent. Therefore, a mechanistic functional traits-based model seems able to capture the link between habitat characteristics and functional traits of organisms, delineating the fundamental portion of an ecological niche, the possibility of predicting LH traits and potential ecological applications in the management of natural coastal resources.

  3. Temporal variation in biodeposit organic content and sinking velocity in long-line shellfish culture

    NASA Astrophysics Data System (ADS)

    Ren, Lihua; Zhang, Jihong

    2016-09-01

    We measured the organic content and sinking velocities of biodeposits from two scallop species ( Chlamys farreri, Patinopecten yessoensis) and abalone ( Haliotis discus hannai) that were cultured on suspended long-lines. Measurements were conducted every two months from April 2010 to February 2011. The shellfish were divided into three size groups (small, middle, and big sizes). At each sample point, we assessed biodeposit organic content, average sinking velocity, the frequency distribution of sinking velocities, and the correlation between organic content and sinking velocity. The organic content of biodeposits varied significantly among months ( P<0.05) and the pattern of change varied among species. Sinking velocities varied significantly, ranging from <0.5 cm/s to >1.9 cm/s. The sinking velocities of biodeposits from C. farreri and P. yessoensis were 0.5-1.5 cm/s and from H. discus hannai were <0.7 cm/s. The organic content was significantly negatively correlated to the sinking velocity of biodeposits in C. farreri ( P<0.001) and P. yessoensis ( P<0.05).

  4. Fish and Shellfish Intake and Diabetes in a Costal Population of the Adriatic.

    PubMed

    Sahay, Rashmi D; Ollberding, Nicholas J; Missoni, Saša; Novokmet, Natalija; Sarac, Jelena; Sarić, Tena; Rao, Marepalli B; Rudan, Pavao; Deka, Ranjan

    2015-06-01

    The objective of the study was to examine the association between fish and shellfish intake and diabetes in an island population, and the design of the study was Cross-sectional. Two independent population-based field surveys were conducted in Hvar Island of the eastern Adriatic coast of Croatia in May 2007 and May 2008, with a total of 1,379 adult participants. In multivariable logistic regression models, total fish intake was positively associated with diabetes prevalence in the total population (OR(Q4 vs. Q1) = 1.64; 95% CI = 1.01-2.66; p-trend = 0.09). Oily fish intake also exhibited a positive association with diabetes prevalence in the total population (OR(Q4 vs. Q1) = 2.22; 95% CI = 1.35-3.64; p-trend = 0.01) and in analyses stratified by body mass index, males and those with a high waist circumference. The study suggests an association between oily fish intake and diabetes in the population of the Hvar Island in Croatia. Longitudinal studies incorporating measures of persistent organic pollutants and local cooking practices are warranted to identify factors in fatty fish that may influence the development or persistence of diabetes. PMID:26753457

  5. Metal concentrations in Maryland`s shellfish: 1970s--1990s

    SciTech Connect

    Murphy, D.L.

    1995-12-31

    Maryland has been monitoring arsenic, cadmium, chromium, copper, lead, mercury and zinc in bivalve shellfish from state waters since the 1960s. The primary bivalve species monitored in Maryland waters are the oyster, Crassostrea virginica and the softshell clam, Mya arenaria. These data have been evaluated for temporal trends. In order to insure that temporal evaluations be based upon data produced using comparable analytical methods, the time period evaluated is not the same for all analytes. For example, while most evaluations are for the period 1974 through 1994, arsenic data were evaluated for the period 1980 through 1994. Data for oyster tissue indicate declines in levels of mercury, cadmium, arsenic, copper and zinc on the order of 70--90%. The major portion of these reductions occurred prior to 1985. These declines are evident from data collected from Maryland`s lower eastern shore, a relatively remote area, as well as from waters closer to larger population centers. Past detection levels for lead and chromium were insufficiently low to detect temporal changes.

  6. Arsenic, cadmium, and manganese levels in shellfish from Map Ta Phut, an industrial area in Thailand, and the potential toxic effects on human cells.

    PubMed

    Rangkadilok, Nuchanart; Siripriwon, Pantaree; Nookabkaew, Sumontha; Suriyo, Tawit; Satayavivad, Jutamaad

    2015-01-01

    Map Ta Phut Industrial Estate is a major industrial area in Thailand for both petrochemical and heavy industries. The release of hazardous wastes and other pollutants from these industries increases the potential for contamination in foods in the surrounding area, especially farmed shellfish. This study determined the arsenic (As), cadmium (Cd), and manganese (Mn) concentrations in the edible flesh of farmed shellfish, including Perna viridis, Meretrix meretrix, and Scapharca inaequivalvis, around the Map Ta Phut area using inductively coupled plasma mass spectrometry. The results showed that shellfish samples contained high levels of total As [1.84-6.42 mg kg(-1) wet weight (ww)]. High Mn concentrations were found in P. viridis and M. meretrix, whereas S. inaequivalis contained the highest Cd. Arsenobetaine (AsB) was found to be the major As species in shellfish (>45% of total As). The in vitro cytotoxicity of these elements was evaluated using human cancer cells (T47D, A549, and Jurkat cells). An observed decrease in cell viability in T47D and Jurkat cells was mainly caused by exposure to inorganic As (iAs) or Mn but not to AsB or Cd. The combined elements (AsB+Mn+Cd) at concentrations predicted to result from the estimated daily intake of shellfish flesh by the local people showed significant cytotoxicity in T47D and Jurkat cells. PMID:24986306

  7. Lipophilic toxin profile in Mytilus galloprovincialis during episodes of diarrhetic shellfish poisoning (DSP) in the N.E. Adriatic Sea in 2006.

    PubMed

    Nincevic Gladan, Zivana; Ujevic, Ivana; Milandri, Anna; Marasovic, Ivona; Ceredi, Alfiero; Pigozzi, Silvia; Arapov, Jasna; Skejic, Sanda

    2011-01-01

    Dinophysis spp. blooms and related shellfish toxicity events of diarrhetic shellfish poisoning (DSP) have been the most reported toxicity event through the Croatian National monitoring program. With the aim to characterize the DSP toxin profile in shellfish farmed in Croatia, for the first time a complete analysis of the toxin profile of Croatian mussels has been carried out using the LC-MS/MS technique. The obtained results showed okadaic acid (OA) as the main toxin contaminating Croatian mussels at that time. The maximum concentration of OA in shellfish tissue was recorded 12 days after the Dinophysis fortii bloom, thus suggesting that rapid growth of the toxin level in the shellfish occurred in the first week after the bloom while it was slower in the second week. Furthermore, the presence of only OA at concentrations which could endanger human health suggests D. fortii as the main organism responsible for the toxic event that occurred in Lim Bay. The presence of gymnodimine and spirolides in Croatian mussel has been detected for the first time, while the presence of yessotoxin and pectenotoxin-2 is confirmed. PMID:21258296

  8. Occurrence of legacy and emerging halogenated organic contaminants in marine shellfish along French coasts.

    PubMed

    Munschy, C; Olivier, N; Veyrand, B; Marchand, P

    2015-01-01

    Current contamination levels of selected legacy, currently-used and emerging halogenated contaminants were monitored in marine shellfish along French coastlines. The studied contaminants included polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenylethane (DBDPE), hexabromobenzene (HBB), 2,2′,4,4′,5,5′-hexabromobiphenyl (BB-153) and perfluorinated compounds (PFCs).BDE-47, BDE-209, BTBPE, HBB and α-HBCDD were detected in 100% of the analyzed samples, whereas BB-153, DBDPE and PFOS were detected at frequencies of 97%, 90% and 55%, respectively. Concentrations were in the pg g−1 ww range and varied as follows: PFOS > BDE-47 ∼ α-HBCDD > BDE-209 > BTBPE ∼ DBDPE > HBB ∼ BB-153. Overall, non-PBDE Brominated Flame Retardants (BFRs) revealed concentrations between 3 and 59 times lower than those of PBDEs.PBDE pattern was dominated by BDE-47, followed by BDE-99 > BDE-100 > BDE-49 > BDE-209 > BDE-154; these 6 congeners represented 94% of the summed ten PBDEs. PFC pattern determination revealed PFOS as the predominant PFC in samples from the English Channel and Atlantic, whereas perfluorocarboxylic acids (PFCAs) prevailed in Mediterranean samples. Temporal trend investigations on archived samples from the Mediterranean coast collected between 1981 and 2012 showed a prevalence of PFOS until 1998; PFCAs subsequently increased and became more abundant than PFOS. High levels of PFCAs were observed until 2008, followed by a decrease and stabilization in 2010–2012. Amongst PFCAs, perfluorotridecanoic acid (PFTrDA) and perfluoroundecanoic acid (PFUnA) were predominant and exhibited similar time trends, suggesting similar sources at the investigated site, home to major industrial activity. PMID:25463258

  9. Occurrence of paralytic shellfish poison in the starfish, Asterias amurensis in Kure Bay, Hiroshima Prefecture, Japan.

    PubMed

    Asakawa, M; Nishimura, F; Miyazawa, K; Noguchi, T

    1997-07-01

    In May 1996, during surveillance on the toxicity of invertebrates such as bivalves inhabiting the coasts of Hiroshima Bay, the starfish Asterias amurensis collected in the estuary of the Nikoh River was found to contain toxins which showed strong paralytic action in mice; the maximum toxicity (as paralytic shellfish poison, PSP) was 8.0 MU/g for whole body and 28.7 MU/g for viscera throughout the monitoring period, March to July 1996. Attempts were made to identify the paralytic toxins in the starfish. They were extracted with 80% ethanol acidified with acetic acid, followed by defatting with dichloromethane. The aqueous layer obtained was treated with activated charcoal and then applied to a Sep-Pak C18 cartridge. The unbound toxic fraction was analyzed by high-performance liquid chromatography techniques. The starfish toxin was rather unexpectedly identified as PSP. It was comprised of high toxic components (gonyautoxin-1; GTX1, GTX2, GTX3, GTX4, decarbamoyl-GTX3; dcGTX3 and dcSTX) as the major components, which accounted for approximately 77 mole% of all components, along with protogonyautoxin-1, 2, 3 and 4 (PX1-4), which are N-sulfocarbamoyl derivatives. Of the high toxic components, GTX1 was present in the largest amounts. It was concluded that the toxin of starfish collected in the estuary of Nikoh River in May 1996 consisted of PSP, which supposedly came via the food chain from toxic bivalves living in the same area. To our knowledge, this is the first report of the occurrence of PSP in starfish. PMID:9248006

  10. Implementation of marine spatial planning in shellfish aquaculture management: modeling studies in a Norwegian fjord.

    PubMed

    Filgueira, Ramon; Grant, Jon; Strand, Øivind

    2014-06-01

    Shellfish carrying capacity is determined by the interaction of a cultured species with its ecosystem, which is strongly influenced by hydrodynamics. Water circulation controls the exchange of matter between farms and the adjacent areas, which in turn establishes the nutrient supply that supports phytoplankton populations. The complexity of water circulation makes necessary the use of hydrodynamic models with detailed spatial resolution in carrying capacity estimations. This detailed spatial resolution also allows for the study of processes that depend on specific spatial arrangements, e.g., the most suitable location to place farms, which is crucial for marine spatial planning, and consequently for decision support systems. In the present study, a fully spatial physical-biogeochemical model has been combined with scenario building and optimization techniques as a proof of concept of the use of ecosystem modeling as an objective tool to inform marine spatial planning. The object of this exercise was to generate objective knowledge based on an ecosystem approach to establish new mussel aquaculture areas in a Norwegian fjord. Scenario building was used to determine the best location of a pump that can be used to bring nutrient-rich deep waters to the euphotic layer, increasing primary production, and consequently, carrying capacity for mussel cultivation. In addition, an optimization tool, parameter estimation (PEST), was applied to the optimal location and mussel standing stock biomass that maximize production, according to a preestablished carrying capacity criterion. Optimization tools allow us to make rational and transparent decisions to solve a well-defined question, decisions that are essential for policy makers. The outcomes of combining ecosystem models with scenario building and optimization facilitate planning based on an ecosystem approach, highlighting the capabilities of ecosystem modeling as a tool for marine spatial planning. PMID:24988780

  11. Dinophysis caudata generated lipophilic shellfish toxins in bivalves from the Nanji Islands, East China Sea

    NASA Astrophysics Data System (ADS)

    Jiang, Tao; Xu, Yixiao; Li, Yang; Qi, Yuzao; Jiang, Tianjiu; Wu, Feng; Zhang, Fan

    2014-01-01

    A 12-month program of monitoring potentially toxic microalgae (that produce lipophilic shellfish toxins; LSTs) and their toxins in bivalves was conducted from April 2006 to March 2007 in the Nanji Islands, East China Sea. Two Dinophysis species, D. caudata and D. acuminata, were identified, and D. caudata was found to be the dominant species. D. caudata was detected in water samples between April and June 2006, and between February and March 2007. It reached its highest abundances in May, with a mean abundance of 1.38×102 cells/L in surface water and 1.25×102 cells/L in bottom water (<10 m deep). The temporal distribution of D. caudata was associated with the occurrence of LSTs in bivalve samples, which mostly occurred at the same time as D. caudata blooms, between April and July 2006. All of the cultured bivalves sampled between April and June were contaminated with LSTs, with an average toxicity of 85 μg okadaic acid (OA) eq./100 g meat, which was four times higher than the Chinese regulatory limit (20 μg OA eq./100 g meat). Ten out of fifteen wild samples (66.7%) collected during the same period were positive for LSTs, and contained an average LST toxicity of 45 μg OA eq./100 g meat (more than twice the regulatory value). Cultured Patinopecten yessoensis collected on 15 May 2006 had the highest toxicity, 320 μg OA eq./100 g meat, and relatively high toxicities (80 to 160 μg OA eq./100 g meat) were found in bivalves until the end of July.

  12. Phylogeography of Cylindrospermopsin and Paralytic Shellfish Toxin-Producing Nostocales Cyanobacteria from Mediterranean Europe (Spain)

    PubMed Central

    Cirés, Samuel; Wörmer, Lars; Ballot, Andreas; Agha, Ramsy; Wiedner, Claudia; Velázquez, David; Casero, María Cristina

    2014-01-01

    Planktonic Nostocales cyanobacteria represent a challenge for microbiological research because of the wide range of cyanotoxins that they synthesize and their invasive behavior, which is presumably enhanced by global warming. To gain insight into the phylogeography of potentially toxic Nostocales from Mediterranean Europe, 31 strains of Anabaena (Anabaena crassa, A. lemmermannii, A. mendotae, and A. planctonica), Aphanizomenon (Aphanizomenon gracile, A. ovalisporum), and Cylindrospermopsis raciborskii were isolated from 14 freshwater bodies in Spain and polyphasically analyzed for their phylogeography, cyanotoxin production, and the presence of cyanotoxin biosynthesis genes. The potent cytotoxin cylindrospermopsin (CYN) was produced by all 6 Aphanizomenon ovalisporum strains at high levels (5.7 to 9.1 μg CYN mg−1 [dry weight]) with low variation between strains (1.5 to 3.9-fold) and a marked extracellular release (19 to 41% dissolved CYN) during exponential growth. Paralytic shellfish poisoning (PSP) neurotoxins (saxitoxin, neosaxitoxin, and decarbamoylsaxitoxin) were detected in 2 Aphanizomenon gracile strains, both containing the sxtA gene. This gene was also amplified in non-PSP toxin-producing Aphanizomenon gracile and Aphanizomenon ovalisporum. Phylogenetic analyses supported the species identification and confirmed the high similarity of Spanish Anabaena and Aphanizomenon strains with other European strains. In contrast, Cylindrospermopsis raciborskii from Spain grouped together with American strains and was clearly separate from the rest of the European strains, raising questions about the current assumptions of the phylogeography and spreading routes of C. raciborskii. The present study confirms that the nostocalean genus Aphanizomenon is a major source of CYN and PSP toxins in Europe and demonstrates the presence of the sxtA gene in CYN-producing Aphanizomenon ovalisporum. PMID:24334673

  13. Paralytic Shellfish Poisoning Toxin-Producing Cyanobacterium Aphanizomenon gracile in Northeast Germany▿ †

    PubMed Central

    Ballot, Andreas; Fastner, Jutta; Wiedner, Claudia

    2010-01-01

    Neurotoxic paralytic shellfish poisoning (PSP) toxins, anatoxin-a (ATX), and hepatotoxic cylindrospermopsin (CYN) have been detected in several lakes in northeast Germany during the last 2 decades. They are produced worldwide by members of the nostocalean genera Anabaena, Cylindrospermopsis, and Aphanizomenon. Although no additional sources of PSP toxins and ATX have been identified in German water bodies to date, the observed CYN concentrations cannot be produced solely by Aphanizomenon flos-aquae, the only known CYN producer in Germany. Therefore, we attempted to identify PSP toxin, ATX, and CYN producers by isolating and characterizing 92 Anabaena, Aphanizomenon, and Anabaenopsis strains from five lakes in northeast Germany. In a polyphasic approach, all strains were morphologically and phylogenetically classified and then tested for PSP toxins, ATX, and CYN by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-linked immunosorbent assay (ELISA) and screened for the presence of PSP toxin- and CYN-encoding gene fragments. As demonstrated by ELISA and LC-MS, 14 Aphanizomenon gracile strains from Lakes Melang and Scharmützel produced four PSP toxin variants (gonyautoxin 5 [GTX5], decarbamoylsaxitoxin [dcSTX], saxitoxin [STX], and neosaxitoxin [NEO]). GTX5 was the most prevalent PSP toxin variant among the seven strains from Lake Scharmützel, and NEO was the most prevalent among the seven strains from Lake Melang. The sxtA gene, which is part of the saxitoxin gene cluster, was found in the 14 PSP toxin-producing A. gracile strains and in 11 non-PSP toxin-producing Aphanizomenon issatschenkoi, A. flos-aquae, Anabaena planktonica, and Anabaenopsis elenkinii strains. ATX and CYN were not detected in any of the isolated strains. This study is the first confirming the role of A. gracile as a PSP toxin producer in German water bodies. PMID:20048055

  14. Helminth parasites of fish and shellfish from the Santa Gilla Lagoon in southern Sardinia, Italy.

    PubMed

    Culurgioni, J; Sabatini, A; De Murtas, R; Mattiucci, S; Figus, V

    2014-12-01

    An extensive survey of helminth parasites in fish and shellfish species from Santa Gilla, a brackish water lagoon in southern Sardinia (western Mediterranean), resulted in the identification of 69 helminth parasite taxa and/or species from 13 fish species (n= 515) and seven bivalve species (n= 2322) examined between September 2001 and July 2011. The list summarizes information on the helminth parasites harboured by fish and molluscs contained in the available literature. Digenea species (37), both adults and larvae, dominated the parasite fauna, whereas Cestoda were the least represented class (three species). Monogenea, Nematoda and Acanthocephala were present with 17, 6 and 6 species, respectively, which were mainly adults. The most widespread parasite species was the generalist Contracaecum rudolphii A (Nematoda). Other species, such as the Haploporidae and Ascocotyle (Phagicola) spp. 1 and 2 (Digenea), showed a high family specificity in Mugilidae. Importantly, the study recorded the occurrence of potential zoonotic agents, such as Heterophyes heterophyes, Ascocotyle (Phagicola) spp. and C. rudolphii A, the latter two reaching the highest indices of infection in the highly marketed fish grey mullet and sea bass, respectively. The highest parasite richness was detected in Dicentrarchus labrax, which harboured 17 helminth species, whereas the lowest value was observed in Atherina boyeri, infected by only three species. The list includes the first geographical record in Italian coastal waters of Robinia aurata and Stictodora sawakinensis, and 30 reports of new host-parasite complexes, including the larval stages of Ascocotyle (Ascocotyle) sp. and Southwellina hispida in D. labrax. PMID:23790066

  15. Detection and quantification of Vibrio parahaemolyticus in shellfish from Italian production areas.

    PubMed

    Suffredini, Elisabetta; Mioni, Renzo; Mazzette, Rina; Bordin, Paola; Serratore, Patrizia; Fois, Federica; Piano, Annamaria; Cozzi, Loredana; Croci, Luciana

    2014-08-01

    Vibrio parahaemolyticus is a marine microorganism, recognized as an important cause of foodborne illness particularly in Asia, South America and United States. Outbreaks are rarely reported in Europe, but they can occur unexpectedly in relation, among other reasons, to the spread of highly virulent strains. It is known that the risk is proportional to exposure levels to pathogenic V. parahaemolyticus (i.e. carrying the tdh and/or the trh genes) but currently there is a lack of occurrence data for pathogenic V. parahaemolyticus in shellfish production areas of the Member States. In this study a total of 147 samples of bivalve molluscs, from harvesting areas of two Italian regions (Sardinia and Veneto) were analyzed for Escherichia coli and salmonella, according to Reg 2073/2005, and for detection and enumeration of total and toxigenic V. parahaemolyticus strains using a new DNA colony hybridization method. Environmental parameters (water temperature and salinity) were also recorded. Results of E. coli were consistently in agreement with the legislation limits for the harvesting class of origin and Salmonella was detected only in one sample. The average contamination levels for total V. parahaemolyticus were 84 and 73 CFU/g respectively for Sardinia and Veneto, with the highest value reaching 8.7 × 10(3)CFU/g. Nineteen samples (12.9%) resulted positive for the presence of potentially pathogenic V. parahaemolyticus strains, with levels ranging between 10 and 120 CFU/g and most of the positive samples (n=17) showing values equal or below 20 CFU/g. A significant correlation (r=0.41) was found between water temperature and V. parahaemolyticus levels, as well as with isolation frequency. The data provided in this study on contamination levels of total and potentially pathogenic V. parahaemolyticus, seasonal distribution and correlation with water temperature, will help in defining appropriate monitoring programs and post-harvest policies for this hazard, improving the

  16. Ancient Clam Gardens Increased Shellfish Production: Adaptive Strategies from the Past Can Inform Food Security Today

    PubMed Central

    Groesbeck, Amy S.; Rowell, Kirsten; Lepofsky, Dana; Salomon, Anne K.

    2014-01-01

    Maintaining food production while sustaining productive ecosystems is among the central challenges of our time, yet, it has been for millennia. Ancient clam gardens, intertidal rock-walled terraces constructed by humans during the late Holocene, are thought to have improved the growing conditions for clams. We tested this hypothesis by comparing the beach slope, intertidal height, and biomass and density of bivalves at replicate clam garden and non-walled clam beaches in British Columbia, Canada. We also quantified the variation in growth and survival rates of littleneck clams (Leukoma staminea) we experimentally transplanted across these two beach types. We found that clam gardens had significantly shallower slopes than non-walled beaches and greater densities of L. staminea and Saxidomus giganteus, particularly at smaller size classes. Overall, clam gardens contained 4 times as many butter clams and over twice as many littleneck clams relative to non-walled beaches. As predicted, this relationship varied as a function of intertidal height, whereby clam density and biomass tended to be greater in clam gardens compared to non-walled beaches at relatively higher intertidal heights. Transplanted juvenile L. staminea grew 1.7 times faster and smaller size classes were more likely to survive in clam gardens than non-walled beaches, specifically at the top and bottom of beaches. Consequently, we provide strong evidence that ancient clam gardens likely increased clam productivity by altering the slope of soft-sediment beaches, expanding optimal intertidal clam habitat, thereby enhancing growing conditions for clams. These results reveal how ancient shellfish aquaculture practices may have supported food security strategies in the past and provide insight into tools for the conservation, management, and governance of intertidal seascapes today. PMID:24618748

  17. A feasibility study into the production of a freeze-dried oyster reference material for paralytic shellfish poisoning toxins.

    PubMed

    Turner, Andrew D; Lewis, Adam M; Hatfield, Robert G; Higman, Wendy A; Burrell, Stephen

    2013-10-01

    Matrix reference materials are an essential component for the validation and quality control of analytical methodologies for the quantitation of marine biotoxins in shellfish. Given the potential advantages of reference materials in powder form, a study was conducted to assess the feasibility for the production of a freeze-dried oyster tissue reference material containing a range of important paralytic shellfish poisoning toxins. One bulk sample of a wet oyster tissue homogenate was generated following mass culturing of toxic Alexandrium and oyster feeding experiments. The bulk tissue was used to prepare untreated wet frozen aliquots with the remainder being freeze-dried and processed into appropriately-sized powder samples. A pre-column oxidation LC-FLD analysis was used to confirm the absence of any chromatographic artefacts resulting from the processing and to confirm acceptable homogeneity of the tissues. Excellent stability over both the short-term (1 month) and long-term (1 year) of the freeze-dried material was demonstrated as compared with the stability of the untreated wet tissue. A post-column oxidation LC-FLD method was used to confirm the absence of toxin epimerisation in freeze-dried tissues which were observed in the wet tissues. Overall the work showed the feasibility of an approach to produce a homogenous freeze-dried oyster matrix material with enhanced stability in comparison to the untreated wet tissue. The potential for use of the process for preparation of large scale production batches of a freeze-dried CRM for paralytic shellfish poisoning toxins has therefore been demonstrated. PMID:23922056

  18. Categorizing the severity of paralytic shellfish poisoning outbreaks in the Gulf of Maine for forecasting and management.

    PubMed

    Kleindinst, Judith L; Anderson, Donald M; McGillicuddy, Dennis J; Stumpf, Richard P; Fisher, Kathleen M; Couture, Darcie A; Hickey, J Michael; Nash, Christopher

    2014-05-01

    Development of forecasting systems for harmful algal blooms (HABs) has been a long-standing research and management goal. Significant progress has been made in the Gulf of Maine, where seasonal bloom forecasts are now being issued annually using Alexandrium fundyense cyst abundance maps and a population dynamics model developed for that organism. Thus far, these forecasts have used terms such as "significant", "moderately large" or "moderate" to convey the extent of forecasted paralytic shellfish poisoning (PSP) outbreaks. In this study, historical shellfish harvesting closure data along the coast of the Gulf of Maine were used to derive a series of bloom severity levels that are analogous to those used to define major storms like hurricanes or tornados. Thirty-four years of PSP-related shellfish closure data for Maine, Massachusetts and New Hampshire were collected and mapped to depict the extent of coastline closure in each year. Due to fractal considerations, different methods were explored for measuring length of coastline closed. Ultimately, a simple procedure was developed using arbitrary straight-line segments to represent specific sections of the coastline. This method was consistently applied to each year's PSP toxicity closure map to calculate the total length of coastline closed. Maps were then clustered together statistically to yield distinct groups of years with similar characteristics. A series of categories or levels was defined ("Level 1: Limited", "Level 2: Moderate", and "Level 3: Extensive") each with an associated range of expected coastline closed, which can now be used instead of vague descriptors in future forecasts. This will provide scientifically consistent and simply defined information to the public as well as resource managers who make decisions on the basis of the forecasts. PMID:25076815

  19. Temporal and Spatial Variation in the Abundance of Total and Pathogenic Vibrio parahaemolyticus in Shellfish in China.

    PubMed

    Han, Haihong; Li, Fengqin; Yan, Weixing; Guo, Yunchang; Li, Ning; Liu, Xiumei; Zhu, Jianghui; Xu, Jin; Chen, Yan; Li, Xiugui; Lv, Hong; Zhang, Yiqian; Cai, Te; Chen, Yuzhen

    2015-01-01

    We investigated the abundance of total and pathogenic Vibrio parahaemolyticus in shellfish sampled from four provinces in China during May 2013 and March 2014 using the most probable number-polymerase chain reaction (MPN-PCR) method. Total V. parahaemolyticus was detected in 67.7% of 496 samples. A total of 38.1% and 10.1% of samples exceeded 1,000 MPN g(-1) and 10,000 MPN g(-1), respectively. V. parahaemolyticus densities followed a seasonal and geographical trend, with Guangxi and Sichuan shellfish possessing total V. parahaemolyticus levels that were 100-fold higher than those of the Liaoning and Shandong regions. Moreover, the levels of V. parahaemolyticus were at least 10-fold higher in the summer and autumn than in the cooler seasons. Pathogenic V. parahaemolyticus levels were generally lower than total V. parahaemolyticus levels by several log units and tended to be high in samples contaminated with high total V. parahaemolyticus levels. The aqua farms had a lower prevalence but higher abundance of total V. parahaemolyticus compared to retail markets. The catering markets showed the lowest levels of total V. parahaemolyticus, but 20.0% of samples exceeded 1,000 MPN g(-1). The levels of both total and pathogenic V. parahaemolyticus in oysters were higher than in clams. The log-transformed abundance of V. parahaemolyticus was significantly correlated with both water temperature and air temperature but not water salinity. These results provide baseline contamination data of V. parahaemolyticus in shellfish in China, which can be applied to local risk assessments to prioritize risk control to key sectors and evaluate the effectiveness of future control measures. PMID:26061712

  20. Categorizing the severity of paralytic shellfish poisoning outbreaks in the Gulf of Maine for forecasting and management

    NASA Astrophysics Data System (ADS)

    Kleindinst, Judith L.; Anderson, Donald M.; McGillicuddy, Dennis J.; Stumpf, Richard P.; Fisher, Kathleen M.; Couture, Darcie A.; Michael Hickey, J.; Nash, Christopher

    2014-05-01

    Development of forecasting systems for harmful algal blooms (HABs) has been a long-standing research and management goal. Significant progress has been made in the Gulf of Maine, where seasonal bloom forecasts are now being issued annually using Alexandrium fundyense cyst abundance maps and a population dynamics model developed for that organism. Thus far, these forecasts have used terms such as “significant”, “moderately large” or “moderate” to convey the extent of forecasted paralytic shellfish poisoning (PSP) outbreaks. In this study, historical shellfish harvesting closure data along the coast of the Gulf of Maine were used to derive a series of bloom severity levels that are analogous to those used to define major storms like hurricanes or tornados. Thirty-four years of PSP-related shellfish closure data for Maine, Massachusetts and New Hampshire were collected and mapped to depict the extent of coastline closure in each year. Due to fractal considerations, different methods were explored for measuring length of coastline closed. Ultimately, a simple procedure was developed using arbitrary straight-line segments to represent specific sections of the coastline. This method was consistently applied to each year’s PSP toxicity closure map to calculate the total length of coastline closed. Maps were then clustered together statistically to yield distinct groups of years with similar characteristics. A series of categories or levels was defined (“Level 1: Limited”, “Level 2: Moderate”, and “Level 3: Extensive”) each with an associated range of expected coastline closed, which can now be used instead of vague descriptors in future forecasts. This will provide scientifically consistent and simply defined information to the public as well as resource managers who make decisions on the basis of the forecasts.

  1. Categorizing the severity of paralytic shellfish poisoning outbreaks in the Gulf of Maine for forecasting and management

    PubMed Central

    Kleindinst, Judith L.; Anderson, Donald M.; McGillicuddy, Dennis J.; Stumpf, Richard P.; Fisher, Kathleen M.; Couture, Darcie A.; Hickey, J. Michael; Nash, Christopher

    2014-01-01

    Development of forecasting systems for harmful algal blooms (HABs) has been a long-standing research and management goal. Significant progress has been made in the Gulf of Maine, where seasonal bloom forecasts are now being issued annually using Alexandrium fundyense cyst abundance maps and a population dynamics model developed for that organism. Thus far, these forecasts have used terms such as “significant”, “moderately large” or “moderate” to convey the extent of forecasted paralytic shellfish poisoning (PSP) outbreaks. In this study, historical shellfish harvesting closure data along the coast of the Gulf of Maine were used to derive a series of bloom severity levels that are analogous to those used to define major storms like hurricanes or tornados. Thirty-four years of PSP-related shellfish closure data for Maine, Massachusetts and New Hampshire were collected and mapped to depict the extent of coastline closure in each year. Due to fractal considerations, different methods were explored for measuring length of coastline closed. Ultimately, a simple procedure was developed using arbitrary straight-line segments to represent specific sections of the coastline. This method was consistently applied to each year’s PSP toxicity closure map to calculate the total length of coastline closed. Maps were then clustered together statistically to yield distinct groups of years with similar characteristics. A series of categories or levels was defined (“Level 1: Limited”, “Level 2: Moderate”, and “Level 3: Extensive”) each with an associated range of expected coastline closed, which can now be used instead of vague descriptors in future forecasts. This will provide scientifically consistent and simply defined information to the public as well as resource managers who make decisions on the basis of the forecasts. PMID:25076815

  2. Use of genomic probes to detect hepatitis A virus and enterovirus RNAs in wild shellfish and relationship of viral contamination to bacterial contamination.

    PubMed Central

    Le Guyader, F; Apaire-Marchais, V; Brillet, J; Billaudel, S

    1993-01-01

    Genomic probes were used to investigate hepatitis A virus (HAV) and enterovirus RNAs in two types of shellfish from natural beds (Atlantic coast, France). After elution concentration, nucleic acid extracted by proteinase K and purified by phenol-chloroform and ethanol precipitation was assayed by dot blot hybridization. The probes used were a specific HAV probe corresponding to the 3' end (3D polymerase coding region) and an enterovirus probe corresponding to the 5' noncoding region. The method was first tested under experimental conditions by using virus-spiked shellfish before being applied under field conditions. Our results show that shellfish were highly contaminated: enterovirus and HAV RNAs were found in 63 and 67%, respectively, of samples examined with the riboprobes. On the same site, viral (HAV and enterovirus) RNAs were found in a larger fraction of cockles than mussels. Statistical tests of dependence showed no relationship between viral contamination and bacterial contamination (evaluated by fecal coliform counts). Images PMID:8285700

  3. Understanding interannual, decadal level variability in paralytic shellfish poisoning toxicity in the Gulf of Maine: The HAB Index

    NASA Astrophysics Data System (ADS)

    Anderson, Donald M.; Couture, Darcie A.; Kleindinst, Judith L.; Keafer, Bruce A.; McGillicuddy, Dennis J., Jr.; Martin, Jennifer L.; Richlen, Mindy L.; Hickey, J. Michael; Solow, Andrew R.

    2014-05-01

    A major goal in harmful algal bloom (HAB) research has been to identify mechanisms underlying interannual variability in bloom magnitude and impact. Here the focus is on variability in Alexandrium fundyense blooms and paralytic shellfish poisoning (PSP) toxicity in Maine, USA, over 34 years (1978-2011). The Maine coastline was divided into two regions - eastern and western Maine, and within those two regions, three measures of PSP toxicity (the percent of stations showing detectable toxicity over the year, the cumulative amount of toxicity per station measured in all shellfish (mussel) samples during that year, and the duration of measurable toxicity) were examined for each year in the time series. These metrics were combined into a simple HAB Index that provides a single measure of annual toxin severity across each region. The three toxin metrics, as well as the HAB Index that integrates them, reveal significant variability in overall toxicity between individual years as well as long-term, decadal patterns or regimes. Based on different conceptual models of the system, we considered three trend formulations to characterize the long-term patterns in the Index - a three-phase (mean-shift) model, a linear two-phase model, and a pulse-decline model. The first represents a “regime shift” or multiple equilibria formulation as might occur with alternating periods of sustained high and low cyst abundance or favorable and unfavorable growth conditions, the second depicts a scenario of more gradual transitions in cyst abundance or growth conditions of vegetative cells, and the third characterizes a ”sawtooth” pattern in which upward shifts in toxicity are associated with major cyst recruitment events, followed by a gradual but continuous decline until the next pulse. The fitted models were compared using both residual sum of squares and Akaike's Information Criterion. There were some differences between model fits, but none consistently gave a better fit than the

  4. Understanding interannual, decadal level variability in paralytic shellfish poisoning toxicity in the Gulf of Maine: the HAB Index

    PubMed Central

    Anderson, Donald M.; Couture, Darcie A.; Kleindinst, Judith L.; Keafer, Bruce A.; McGillicuddy, Dennis J.; Martin, Jennifer L.; Richlen, Mindy L.; Hickey, J. Michael; Solow, Andrew R.

    2013-01-01

    A major goal in harmful algal bloom (HAB) research has been to identify mechanisms underlying interannual variability in bloom magnitude and impact. Here the focus is on variability in Alexandrium fundyense blooms and paralytic shellfish poisoning (PSP) toxicity in Maine, USA, over 34 years (1978 – 2011). The Maine coastline was divided into two regions -eastern and western Maine, and within those two regions, three measures of PSP toxicity (the percent of stations showing detectable toxicity over the year, the cumulative amount of toxicity per station measured in all shellfish (mussel) samples during that year, and the duration of measurable toxicity) were examined for each year in the time series. These metrics were combined into a simple HAB Index that provides a single measure of annual toxin severity across each region. The three toxin metrics, as well as the HAB Index that integrates them, reveal significant variability in overall toxicity between individual years as well as long-term, decadal patterns or regimes. Based on different conceptual models of the system, we considered three trend formulations to characterize the long-term patterns in the Index – a three-phase (mean-shift) model, a linear two-phase model, and a pulse-decline model. The first represents a “regime shift” or multiple equilibria formulation as might occur with alternating periods of sustained high and low cyst abundance or favorable and unfavorable growth conditions, the second depicts a scenario of more gradual transitions in cyst abundance or growth conditions of vegetative cells, and the third characterizes a ”sawtooth” pattern in which upward shifts in toxicity are associated with major cyst recruitment events, followed by a gradual but continuous decline until the next pulse. The fitted models were compared using both residual sum of squares and Akaike's Information Criterion. There were some differences between model fits, but none consistently gave a better fit than

  5. Two quantitative real-time PCR assays for the detection of penaeid shrimp and blue crab, crustacean shellfish allergens.

    PubMed

    Eischeid, Anne C; Kim, Bang-hyun; Kasko, Sasha M

    2013-06-19

    Food allergen detection methods must be able to specifically detect minute quantities of an allergenic food in a complex food matrix. One technique that can be used is real-time PCR. For the work described here, real-time PCR assays were developed to detect penaeid shrimp and blue crab, crustacean shellfish allergens. The method was tested using shrimp meat and crab meat spiked into several types of foods, including canned soups, deli foods, meat, seafood, and prepared seafood products. Foods were spiked with either shrimp or crab at levels ranging from 0.1 to 10⁶ parts per million (ppm) and analyzed either raw or cooked by a variety of methods. Real-time PCR data were used to generate linear standard curves, and assays were evaluated with respect to linear range and reaction efficiency. Results indicate that both assays performed well in a variety of food types. High reaction efficiencies were achieved across a linear range of 6-8 orders of magnitude. Limits of detection were generally between 0.1 and 1 ppm. Cooking methods used to simulate thermal processing of foods had little effect on assay performance. This work demonstrates that real-time PCR can be a valuable tool in the detection of crustacean shellfish. PMID:23190158

  6. Methods for routine control of irradiated food: Determination of the irradiation status of shellfish by thermoluminescence analysis

    NASA Astrophysics Data System (ADS)

    Schreiber, G. A.; Hoffmann, A.; Helle, N.; Bögl, K. W.

    1994-06-01

    In some countries, clearance has been given for treating certain types of shellfish by ionizing radiation in order to increase the shelf-life and to reduce health hazards which might be caused by contaminating microorganisms. In the present study, thermoluminescence (TL) analysis was used to examine the irradiation status of shellfish products purchased from local suppliers. For analysis minerals were isolated from the guts of the animals. Although on none of the examined products an irradiation treatment prior to analysis could be shown, the results obtained on non-irradiated and irradiated products have revealed that irradiation within the commercially used dose range can clearly be detected. Already first glow TL intensities of minerald indicated irradiation treatments. Normalized TL signals of non-irradiated and irradiated samples were clearly separated. By calculation of differences of TL intensities and TL signals between non-irradiated and irradiated samples in dependency of integration temperature an optimized integration area for glow curves was determined. The result of this study agree well with results obtained by two large-scale intercomparisons between food control laboratories to detect irradiation treatment of spices and herbal products as well as of fruit and vegetables by TL analysis of contaminating minerals.

  7. Effects of past, present, and future ocean carbon dioxide concentrations on the growth and survival of larval shellfish

    PubMed Central

    Gobler, Christopher J.

    2010-01-01

    The combustion of fossil fuels has enriched levels of CO2 in the world’s oceans and decreased ocean pH. Although the continuation of these processes may alter the growth, survival, and diversity of marine organisms that synthesize CaCO3 shells, the effects of ocean acidification since the dawn of the industrial revolution are not clear. Here we present experiments that examined the effects of the ocean’s past, present, and future (21st and 22nd centuries) CO2 concentrations on the growth, survival, and condition of larvae of two species of commercially and ecologically valuable bivalve shellfish (Mercenaria mercenaria and Argopecten irradians). Larvae grown under near preindustrial CO2 concentrations (250 ppm) displayed significantly faster growth and metamorphosis as well as higher survival and lipid accumulation rates compared with individuals reared under modern day CO2 levels. Bivalves grown under near preindustrial CO2 levels displayed thicker, more robust shells than individuals grown at present CO2 concentrations, whereas bivalves exposed to CO2 levels expected later this century had shells that were malformed and eroded. These results suggest that the ocean acidification that has occurred during the past two centuries may be inhibiting the development and survival of larval shellfish and contributing to global declines of some bivalve populations. PMID:20855590

  8. Survey of subsistence fish and shellfish for exposure to oil spilled from the Exxon Valdez. First year: 1989. Technical memo

    SciTech Connect

    Varanasi, U.; Chan, S.L.; MacLeod, W.D.; Stein, J.E.; Brown, D.W.

    1990-12-01

    More than 500 fish and shellfish samples collected from native Alaskan fishing grounds were analyzed for aromatic contaminants (ACs) from petroleum (alkylated and unsubstituted aromatic hydrocarbons with 2-7 benzenoid rings and dibenzothiophenes). Intertidal molluscs (mussels, clams, chitons, and snails) from Windy Bay, Kodiak (City), Chenega Bay, and Old Harbor consistently had more than 100 parts-per-billion (ppb) ACs, with levels in mussels from Windy Bay and Kodiak as high as 12,000 to 18,000 ppb. Levels of ACs in molluscs, crabs, and sea urchins from other villages were less than 10 ppb, a level comparable to that measured in shellfish from the designated reference area in Southeast Alaska near Angoon. Nonparametric statistics on 147 samples of molluscs showed that levels of ACs in molluscs from Windy Bay, Kodiak, and Chenega Bay were significantly higher (p = or < 0.05) than those in the Angoon molluscs sampled. In an unofficial advisory opinion, the Food and Drug Administration has indicated that little risk is involved in the consumption of the nonsmoked subsistence foods studied.

  9. Detection of paralytic shellfish toxins by a solid-phase inhibition immunoassay using a microsphere-flow cytometry system.

    PubMed

    Fraga, María; Vilariño, Natalia; Louzao, M Carmen; Campbell, Katrina; Elliott, Christopher T; Kawatsu, Kentaro; Vieytes, Mercedes R; Botana, Luis M

    2012-05-15

    Paralytic shellfish poisoning is a toxic syndrome described in humans following the ingestion of seafood contaminated with saxitoxin and/or its derivatives. The presence of these toxins in shellfish is considered an important health threat and their levels in seafood destined to human consumption are regulated in many countries, as well as the levels of other chemically unrelated toxins. We studied the feasibility of immunodetection of saxitoxin and its analogs using a solid-phase microsphere assay coupled to flow cytometry detection in a Luminex 200 system. The technique consists of a competition assay where the toxins in solution compete with bead-bound saxitoxin for binding to an antigonyautoxin 2/3 monoclonal antibody (GT-13A). The assay allowed the detection of saxitoxin both in buffer and mussel extracts in the range of 2.2-19.7 ng/mL (IC(20)-IC(80)). Moreover, the assay cross-reactivity with other toxins of the group is similar to previously published immunoassays, with adequate detection of most analogs except N-1 hydroxy analogs. The recovery rate of the assay for saxitoxin was close to 100%. This microsphere-based immunoassay is suitable to be used as a screening method, detecting saxitoxin from 260 to 2360 μg/kg. This microsphere/flow cytometry system provided similar sensitivities to previously published immunoassays and provides a solid background for the development of easy, flexible multiplexing of toxin detection in one sample. PMID:22500610

  10. Methyl mercury concentrations in edible fish and shellfish from Dunedin, and other regions around the South Island, New Zealand.

    PubMed

    Sadhu, Ashish K; Kim, Jonathan P; Furrell, Hamish; Bostock, Ben

    2015-12-15

    Methyl mercury (MeHg) concentrations were determined in edible fish and shellfish available in local markets in Dunedin, New Zealand. While most of the fish species were sourced in Dunedin, some specimens of fish were also collected from waters off Picton, around Stewart Island and also off-shore of the South Island in the Puysegur and Subantarctic regions. The concentrations of MeHg were analysed in 25 different fish species and shellfish (103 muscle tissue samples). Total mercury (HgT) levels were also analysed in a few (n=12) selected fish samples. Most of the Hg was in the form of MeHg (≥ 96%). Higher MeHg concentrations were found in fish at higher trophic levels, particularly in predatory fish species such as ling, school shark, spiny dogfish and albacore tuna. Concentrations of MeHg in all samples ranged from 0.002 to 2.515 μg MeHg/g. PMID:26478458

  11. Human health risk assessment of heavy metals in tropical fish and shellfish collected from the river Buriganga, Bangladesh.

    PubMed

    Ahmed, Md Kawser; Baki, Mohammad Abdul; Islam, Md Saiful; Kundu, Goutam Kumar; Habibullah-Al-Mamun, Md; Sarkar, Santosh Kumar; Hossain, Md Muzammel

    2015-10-01

    Although fish, crustacean, and shellfish are significant sources of protein, they are currently affected by rapid industrialization, resulting in increased concentrations of heavy metals. Accumulation of heavy metals (V, Cr, Mn, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sb, Ba, and Pb) and associated human health risk were investigated in three fish species, namely Ailia coila, Gagata youssoufi, and Mastacembelus pancalus; one crustacean (prawn), Macrobrachium rosenbergii; and one Gastropoda, Indoplanorbis exustus, collected from the Buriganga River, Bangladesh. Samples were collected from the professional fishermen. Cu was the most accumulated metal in M. rosenbergii. Ni, As, Ag, and Sb were in relatively lower concentrations, whereas relatively higher accumulation of Cr, Mn, Zn, and Se were recorded. Mn, Zn, and Pb were present in higher concentrations than the guidelines of various authorities. There were significant differences in metal accumulation among different fish, prawn, or shellfish species. Target hazard quotient (THQ) and target cancer risk (TR) were calculated to estimate the non-carcinogenic and carcinogenic health risks, respectively. The THQ for individual heavy metals were below 1 suggesting no potential health risk. But combined impact, estimated by hazard index (HI), suggested health risk for M. pancalus consumption. Although consumption of fish at current accumulation level is safe but continuous and excess consumption for a life time of more than 70 years has probability of target cancer risk. PMID:26044144

  12. Upwelling of Acidified Water: Not Just an Issue for Shellfish Hatcheries on the West Coast of the US

    NASA Astrophysics Data System (ADS)

    Poach, M.; Munroe, D.; Abrahamsen, I.

    2014-12-01

    Periodic upwelling events are known to occur off the coast of New Jersey during the summer. As with upwelling off the US West Coast, these events can transport acidified water to the surface and shoreward. To determine if upwelling events have the potential to impact shellfish hatcheries in New Jersey, a monitoring study was conducted at the Aquaculture Innovation Center (AIC) of Rutgers University. The AIC is an important hatchery supporting the New Jersey oyster aquaculture industry through the production of disease resistant seed oysters. Starting in June of 2014, temperature, salinity, dissolved oxygen and pH were continuously monitored at the AIC's intake pipe. Periodic grab samples were also collected at the intake and at locations within the facility. Grab samples were preserved and analyzed for pH and dissolved inorganic carbon (DIC). DIC and pH were used to calculate the aragonite saturation state of the sampled water. During an upwelling event in early July a drop in pH was measured at the intake. Grab samples showed that water of lower pH and aragonite saturation was entering the facility. These results show that hatcheries along the NJ coast need to be aware that upwelling events may bring conditions detrimental for shellfish production.

  13. Fluorogenic Membrane Overlays to Enumerate Total and Fecal Escherichia coli and Total Vibrionaceae in Shellfish and Seawater.

    PubMed

    Richards, Gary P; Watson, Michael A

    2010-01-01

    Three assays were developed to enumerate total and fecal Escherichia coli and total Vibrionaceae in shellfish, seawater, and other foods and environmental samples. Assays involve membrane overlays of overnight colonies on nonselective agar plates to detect beta-glucuronidase and lysyl aminopeptidase activities for E. coli and Vibrionaceae, respectively. Cellulose membranes containing the substrates 4-methylumbeferyl-beta-D-glucuronide (MUG) produced a bright blue fluorescence when overlaid onto E. coli, while L-lysyl-7-amino-4-trifluoromethylcoumarin produced green fluorescent foci when overlaid onto Vibrionaceae family members. A multiplex assay was also developed for simultaneously enumerating total E. coli and total Vibrionaceae in oysters and seawater. Overall, 65% of overlaid E. coli (non-O157:H7) were MUG-positive, compared with 62% as determined by the most-probable-number-MUG assay. The overlays are rapid, simple, and cost effective for quantification purposes. This research provides practical alternatives for monitoring bacterial indicators and potential pathogens in complex samples, including molluscan shellfish. PMID:20396663

  14. Virulence and Antibiotic and Heavy Metal Resistance of Vibrio parahaemolyticus Isolated from Crustaceans and Shellfish in Shanghai, China.

    PubMed

    Hu, Qiongxia; Chen, Lanming

    2016-08-01

    Vibrio parahaemolyticus can cause serious human seafoodborne gastroenteritis and even death. In this study, we isolated and characterized 208 V. parahaemolyticus strains from 10 species of commonly consumed crustaceans and shellfish available in fish markets in Shanghai, People's Republic of China, in 2014. Most of these aquatic species had not been detected previously. The results revealed an extremely low occurrence of pathogenic V. parahaemolyticus carrying the toxin gene trh (1.9%). However, a high level of resistance to the antibiotics ampicillin (94.2%), rifampin (93.3%), and streptomycin (77.9%) was found. Approximately 74.5% of the isolates had multidrug-resistant phenotypes. Tolerance to the heavy metals Cu(2+), Pb(2+), and Cd(2+) was detected in the majority of antibiotic resistant isolates. The resistance patterns differed depending on the tested samples. The crustaceans Penaeus monodon and Marsupenaeus japonicus harbored more antibiotic-resistant bacteria, whereas the isolates from the crustacean Litopenaeus vannamei and the shellfish Busycon canaliculatus had high tolerance to eight heavy metals tested. In contrast to the wide distribution of multidrug resistance and tolerance to heavy metals, lower percentages of plasmid DNA (22.6%) and SXT/R391-like integrative and conjugative elements (4.8%) were detected in the isolates, suggesting that V. parahaemolyticus in these aquatic species may have adopted some other molecular mechanisms that mediated the high prevalence of resistance determinants. The results of this study support the need for food safety risk assessment of aquatic products. PMID:27497124

  15. Temperature effects on kinetics of paralytic shellfish toxin elimination in Atlantic surfclams, Spisula solidissima

    NASA Astrophysics Data System (ADS)

    Monica Bricelj, V.; Cembella, Allan D.; Laby, David

    2014-05-01

    Surfclams, Spisula solidissima, pose a particular health risk for human consumption as they are characterized by accumulation of extremely high levels of toxins associated with paralytic shellfish poisoning (PSP), slow toxin elimination and an extremely high post-ingestive capacity for toxin bioconversion. Surfclam populations experience a wide range of temperatures along the NW Atlantic continental shelf, and are undergoing range contraction that has been attributed to global warming. In this study the influence of temperature (5, 12 and 21 °C) on detoxification kinetics of individual PSP toxins in two tissue compartments of juvenile surfclams (∼35 mm shell length) was determined under controlled laboratory conditions, over prolonged (2.4 months) depuration. Clams were toxified with a representative regional Gulf of Maine isolate of the dinoflagellate Alexandrium fundyense of known toxin profile, allowing tracking of changes in toxin composition and calculated toxicity in surfclam tissues. The visceral mass detoxified at all temperatures, although toxin loss rate increased with increasing temperature. In contrast, total toxin content and calculated toxicities in other tissues remained constant or even increased during depuration, suggesting a physiological or biochemical toxin-retention mechanism in this tissue pool and temperature-independent detoxification. In vivo toxin compositional changes in surfclam tissues found in this study provide evidence of specific toxin conversion pathways, involving both reductive and decarbamoylation pathways. We conclude that such toxin biotransformations, especially in non-visceral tissues, may introduce a discrepancy in describing kinetics of total toxicity (in saxitoxin equivalents [STXeq]) of S. solidissima over prolonged detoxification. Nevertheless, use of total toxicity values generated by routine regulatory monitoring based upon mouse bioassays or calculated from chemical analytical determination of molar toxin

  16. Accumulation and depuration of cyanobacterial paralytic shellfish toxins by the freshwater mussel Anodonta cygnea.

    PubMed

    Pereira, Paulo; Dias, Elsa; Franca, Susana; Pereira, Elisa; Carolino, Manuela; Vasconcelos, Vitor

    2004-07-14

    The increasing frequency by which the production of paralytic shellfish toxins (PST) by freshwater bloom-forming cyanobacteria is being noticed world-wide raises the possibility of PST bioaccumulation by freshwater mussels. This study evaluates PST accumulation and depuration by the freshwater mussel Anodonta cygnea exposed over a 14-day period to high densities (mean = 1.4 x 10(9) cells1(-1), S.D. = 0.29 x 10(9) cellsl(-1)) of the toxic cyanobacterium Aphanizomenon issatschenkoi (corresponding to a mean toxin concentration of 25.5 nmol PSTl(-1), S.D. = 9.9 nmol PSTl(-1)). Mussels were subsequently detoxified either by starvation or by feeding on the non-toxic green-algae Ankistodesmus falcatus. Filter feeding activity and toxin uptake by the mussels were followed by cell counting and toxin analysis in water samples taken before and after each daily water renewal. The accumulation and depuration of PST as well as the anatomical distribution of toxins were monitored throughout the experiment by HPLC analysis of mussel extracts. Mussels fed the toxic cyanobacterium removed on average 65.3% of cells and 40.36% of total PST daily provided. Daily rates of cell clearance (% of initial) were negatively correlated with the amounts of PST daily provided (but not with the amount of cells). This suggests a negative effect of toxins on the feeding behaviour of mussels. Small amounts of toxins could be detected in the mussels after the second day of exposure, reaching a maximum of 26 microg PST100 g(-1) by day 7. The viscera contained the greatest proportion of toxins (78%) at the start of the toxification. However, increasing amounts of PST were found in the remaining tissues (gills, mantle and foot) over time. Toxins detected in the mussel extracts were the same provided in the dietary A. issatschenkoi. Nevertheless, mussels showed a higher proportion of saxitoxin and decarbomoylsaxitoxin and a lower proportion of gonyautoxin-5 than the fed cyanobacterium. Similar depuration

  17. In Silico Analysis of Putative Paralytic Shellfish Poisoning Toxins Export Proteins in Cyanobacteria

    PubMed Central

    Soto-Liebe, Katia; López-Cortés, Xaviera A.; Fuentes-Valdes, Juan José; Stucken, Karina; Gonzalez-Nilo, Fernando; Vásquez, Mónica

    2013-01-01

    Paralytic shellfish poisoning toxins (PSTs) are a family of more than 30 natural alkaloids synthesized by dinoflagellates and cyanobacteria whose toxicity in animals is mediated by voltage-gated Na+ channel blocking. The export of PST analogues may be through SxtF and SxtM, two putative MATE (multidrug and toxic compound extrusion) family transporters encoded in PSTs biosynthetic gene cluster (sxt). sxtM is present in every sxt cluster analyzed; however, sxtF is only present in the Cylindrospermopsis-Raphidiopsis clade. These transporters are energetically coupled with an electrochemical gradient of proton (H+) or sodium (Na+) ions across membranes. Because the functional role of PSTs remains unknown and methods for genetic manipulation in PST-producing organisms have not yet been developed, protein structure analyses will allow us to understand their function. By analyzing the sxt cluster of eight PST-producing cyanobacteria, we found no correlation between the presence of sxtF or sxtM and a specific PSTs profile. Phylogenetic analyses of SxtF/M showed a high conservation of SxtF in the Cylindrospermopsis-Raphidiopsis clade, suggesting conserved substrate affinity. Two domains involved in Na+ and drug recognition from NorM proteins (MATE family) of Vibrio parahaemolyticus and V. cholerae are present in SxtF/M. The Na+ recognition domain was conserved in both SxtF/M, indicating that Na+ can maintain the role as a cation anti-transporter. Consensus motifs for toxin binding differed between SxtF and SxtM implying differential substrate binding. Through protein modeling and docking analysis, we found that there is no marked affinity between the recognition domain and a specific PST analogue. This agrees with our previous results of PST export in R. brookii D9, where we observed that the response to Na+ incubation was similar to different analogues. These results reassert the hypothesis regarding the involvement of Na+ in toxin export, as well as the motifs L398XGLQD

  18. The seasonality of fecal coliform bacteria pollution and its influence on closures of shellfish harvesting areas in Mississippi Sound.

    PubMed

    Chigbu, Paulinus; Gordon, Scott; Tchounwou, Paul B

    2005-08-01

    Runoff from agricultural lands and farm animal feedlots is one of the major sources of fecal coliforms in surface waters, and fecal coliform (FC) bacteria concentrations tend to vary with season because of seasonal variations in climatic factors. However, El Niño--Southern Oscillation (ENSO) events may affect the extent and patterns of seasonality in FC levels in coastal waters. Water quality monitoring data for shellfish management collected during El Niño (1990, 1992, 1997), and La Niña (1999, 2000) years were analyzed to evaluate the extent to which these events influenced Pearl River stage, and bacterial levels, water temperature, and salinity in the western part of Mississippi Sound. Models to predict FC levels in relation to various environmental factors were also developed. In 1990, 1992 and 1997, FC geometric mean counts peaked in late winter (January/February) reaching 120 MPN (February 1990), 165 MPN (January 1992), and 86 MPN (January 1997), and then decreased considerably during spring and summer (1.2 - 19 MPN). Thereafter, FC abundance increased slightly in fall and early winter (1.9 - 24 MPN). Fecal coliform abundance during the 2000 La Niña year was much lower (1.0 -10.3 MPN) than in 1992 (1.2 - 165 MPN), and showed no seasonal pattern from January to August, perhaps due to the relative scarcity of rainfall in 2000. In 1995 (ENSO neutral year), peak geometric mean FC count (46 MPN) was lower than during El Niño years and occurred in early spring (March). The seasonal and between year variations in FC levels determined the number of days during which the conditionally approved shellfish growing area was opened for harvesting shellfish. For example, from January to April 1997, the area was not opened for shellfish harvesting, whereas in 2000, the number of days during which the area was opened ranged from 6 - 27 (January to April) to 24 - 26 (October to December). ENSO events thus influenced the extent and timing of the peak levels of fecal

  19. Development of a sensitive and selective liquid chromatography-mass spectrometry method for high throughput analysis of paralytic shellfish toxins using graphitised carbon solid phase extraction.

    PubMed

    Boundy, Michael J; Selwood, Andrew I; Harwood, D Tim; McNabb, Paul S; Turner, Andrew D

    2015-03-27

    Routine regulatory monitoring of paralytic shellfish toxins (PST) commonly employs oxidative derivitisation and complex liquid chromatography fluorescence detection methods (LC-FL). The pre-column oxidation LC-FL method is currently implemented in New Zealand and the United Kingdom. When using this method positive samples are fractionated and two different oxidations are required to confirm the identity and quantity of each PST analogue present. There is a need for alternative methods that are simpler, provide faster turnaround times and have improved detection limits. Hydrophilic interaction liquid chromatography (HILIC) HPLC-MS/MS analysis of PST has been used for research purposes, but high detection limits and substantial sample matrix issues have prevented it from becoming a viable alternative for routine monitoring purposes. We have developed a HILIC UPLC-MS/MS method for paralytic shellfish toxins with an optimised desalting clean-up procedure on inexpensive carbon solid phase extraction cartridges for reduction of matrix interferences. This represents a major technical breakthrough and allows sensitive, selective and rapid analysis of paralytic shellfish toxins from a variety of sample types, including many commercially produced bivalve molluscan shellfish species. Additionally, this analytical approach avoids the need for complex calculations to determine sample toxicity, as unlike other methods each PST analogue is able to be quantified as a single resolved peak. This article presents the method development and optimisation information. A thorough single laboratory validation study has subsequently been performed and this data will be presented elsewhere. PMID:25704772

  20. Possible Influence of Natural Events on Heavy Metals Exposure from Shellfish Consumption: A Case Study in the North-East of Italy

    PubMed Central

    Losasso, Carmen; Bille, Laura; Patuzzi, Ilaria; Lorenzetto, Monica; Binato, Giovanni; Dalla Pozza, Manuela; Ferrè, Nicola; Ricci, Antonia

    2015-01-01

    The objective of this study was the estimation of the exposure over time to heavy metals (cadmium, mercury, and lead) due to shellfish consumption in the Veneto Region, Italy. Shellfish consumption was investigated by a food frequency consumption survey. Altogether, 1949 households, stratified into the five most populated areas of the Veneto Region, were involved in the study. Exposure estimation to heavy metals was carried out taking into account the level of metal measured in samples of Manila clams (Ruditapes philippinarum) and grooved carpet shell (Ruditapes decussatus), collected in the frame of the monitoring activities of mollusk production areas of Veneto Region, between January 2007 and December 2012. A general high contribution of the considered shellfish to the Tolerable Weekly Intake was noticed in the case of cadmium, especially in 2011, when a considerable increase in cadmium intake was estimated. This was probably due to a heavy rainfall event that triggered catastrophic flooding with high impact on shellfish capture areas in November 2010. The results strongly emphasize the importance of dealing with food safety in a holistic way, taking into account the potential impact of extraordinary natural events on food chain contamination, in order to identify food hazards at an early stage, before developing into a real risk for consumers. PMID:25699249

  1. Paralytic shellfish toxins in clinical matrices: Extension of AOAC official method 2005.06 to human urine and serum and application to a 2007 case study in Maine

    NASA Astrophysics Data System (ADS)

    DeGrasse, Stacey; Rivera, Victor; Roach, John; White, Kevin; Callahan, John; Couture, Darcie; Simone, Karen; Peredy, Tamas; Poli, Mark

    2014-05-01

    Paralytic shellfish poisoning (PSP), a potentially fatal foodborne illness, is often diagnosed anecdotally based on symptoms and dietary history. The neurotoxins responsible for PSP, collectively referred to as the saxitoxins or paralytic shellfish toxins (PSTs), are natural toxins, produced by certain dinoflagellates, that may accumulate in seafood, particularly filter-feeding bivalves. Illnesses are rare because of effective monitoring programs, yet occasional poisonings occur. Rarely are contaminated food and human clinical samples (e.g., urine and serum) available for testing. There are currently few methods, none of which are validated, for determining PSTs in clinical matrices. This study evaluated AOAC (Association of Analytical Communities) Official Method of Analysis (OMA) 2005.06. [AOAC Official Method 2005.06 Paralytic Shellfish Poisoning Toxins in Shellfish: Prechormatographic Oxidation and Liquid Chromatography with Fluorescence Detection. In Official Methods of Analysis of AOAC International ], validated only for shellfish extracts, for its extension to human urine and serum samples. Initial assessment of control urine and serum matrices resulted in a sample cleanup modification when working with urine to remove hippuric acid, a natural urinary compound of environmental/dietary origin, which co-eluted with saxitoxin. Commercially available urine and serum matrices were then quantitatively spiked with PSTs that were available as certified reference materials (STX, dcSTX, B1, GTX2/3, C1/2, NEO, and GTX1/4) to assess method performance characteristics. The method was subsequently applied successfully to a PSP case study that occurred in July 2007 in Maine. Not only were PSTs identified in the patient urine and serum samples, the measured time series also led to the first report of human PST-specific urinary elimination rates. The LC-FD data generated from this case study compared remarkably well to results obtained using AOAC

  2. Paralytic shellfish poisoning: post-mortem analysis of tissue and body fluid samples from human victims in the Patagonia fjords.

    PubMed

    García, Carlos; del Carmen Bravo, María; Lagos, Marcelo; Lagos, Néstor

    2004-02-01

    In July 5, 2002 fishermen working in harvesting sea urchin (Loxechinus albus) in the Patagonia Chilean fjords were intoxicated by consumption of filter-feeder bivalve Aulacomya ater. After the ingestion of 7-9 ribbed mussel, two fishermen died 3-4 h after shellfish consumption. The forensic examination in both victims did not show pathological abnormalities with the exception of the lungs conditions, crackling to the touch, pulmonary congestion and edema. The toxic mussel sample showed a toxicity measured by mouse bioassay of 8575 microg of STX (saxitoxin) equivalent by 100 g of shellfish meat. Using post-column derivatization HPLC method with fluorescent on line detection was possible to measure mass amount of each paralytic shellfish poisoning (PSP) toxin yielding individual toxin concentrations. These PSP toxins were identified in the gastric content, body fluids (urine, bile and cerebrospinal fluid) and tissue samples (liver, kidney, lung, stomach, spleen, heart, brain, adrenal glands, pancreas and thyroids glands). The toxin profiles of each body fluid and tissue samples and the amount of each PSP toxin detected are reported. The PSP toxins found in the gastric content, were STX and the gonyautoxins (GTX4, GTX1, GTX5, GTX3 and GTX2) which showed to be the major amount of PSP toxins found in the victims biological samples. The PSP toxin composition in urine and bile showed as major PSP toxins neoSaxitoxin (neoSTX) and GTX4/GTX1 epimers, both STX analogues with an hydroxyl group (-OH) in the N(1) of the tetrahydropurine nucleus. The neoSTX was not present in the gastric content sample, indicating that the oxidation of N(1) in the STX tetrahydropurine nucleus resulted neoSTX, in a similar way that GTX3/GTX2 epimers were transformed in GTX4/GTX1 epimers. Beside this metabolic transformation, also the hydrolysis of carbamoyl group from STX to form its decarbomoyl analogue decarbamoylsaxitoxin was detected in liver, kidney and lung. These two findings show that PSP

  3. Differentiation of fecal Escherichia coli from human, livestock, and poultry sources by rep-PCR DNA fingerprinting on the shellfish culture area of East China Sea.

    PubMed

    Ma, Hong-Jia; Fu, Ling-Lin; Li, Jian-Rong

    2011-05-01

    The rep-PCR DNA fingerprinting performed with REP, BOX A1R, and (GTG)(5) primers was investigated as a way to differentiate between human, livestock, and poultry sources of fecal pollution on the area of Xiangshan Bay, East China Sea. Of the three methods, the BOX-PCR DNA fingerprints analyzed by jack-knife algorithm were revealed high rate of correct classification (RCC) with 91.30, 80.39, 89.39, 86.14, 93.24, 87.72, and 89.28% of human, cattle, swine, chicken, duck, sheep, and goose E. coli isolates classified into the correct host source, respectively. The average rate of correct classification (ARCC) of REP-, BOX-, and (GTG)(5)-PCR patterns was 79.88, 88.21, and 86.39%, respectively. Although the highest amount of bands in (GTG)(5)-PCR fingerprints could be observed, the discriminatory efficacy of BOX-PCR was superior to both REP- and (GTG)(5)-PCR. Moreover, the similarity of 459 isolates originated from shellfish and growing water was compared with fecal-obtained strains. The results showed that 92.4 and 96.2% E. coli strains isolated from midstream and downstream shellfish samples, respectively, had a ≥ 80% similarity with corresponding strains isolated from fecal samples. It was indicated that E. coli in feces could spread from human sewage or domestic farms to the surrounding shellfish culture water, and potentially affect the quality of shellfish. This work suggests that rep-PCR fingerprinting can be a promising genotypic tool applied in the shellfish growing water management on East China Sea for source identification of fecal pollution. PMID:21279641

  4. Feasibility of gymnodimine and 13-desmethyl C spirolide detection by fluorescence polarization using a receptor-based assay in shellfish matrixes.

    PubMed

    Fonfría, Eva S; Vilariño, Natalia; Espiña, Begoña; Louzao, M Carmen; Alvarez, Mercedes; Molgó, Jordi; Aráoz, Rómulo; Botana, Luis M

    2010-01-01

    The detection of toxins in shellfish through reliable methods is essential for human health preservation and prevention of economic losses in the aquaculture industry. Although no human intoxication has been unequivocally linked to gymnodimines or spirolides, these phycotoxins are highly toxic by intraperitoneal injection causing false positives in lipophilic toxin detection by the mouse bioassay. Based on the detection of molecular interactions by fluorescence polarization an inhibition assay was developed using fluorescent alpha-bungarotoxin and nicotinic acetylcholine receptor-enriched membranes of Torpedo marmorata to detect gymnodimine and 13-desmethyl C spirolide. Both toxins, classified into the cyclic imine group, inhibit the interaction of alpha-bungarotoxin with Torpedo nicotinic acetylcholine receptors in the nM range. In this study we analyze the matrix effect of four shellfish species on the fluorescence polarization assay. Mussels, clams, cockles and scallops were extracted with acetone and sequentially partitioned with n-hexane and chloroform. The interference of these shellfish extracts with the alpha-bungarotoxin fluorescence or its binding to the nicotinic acetylcholine receptor was lower than 11%. The average recovery rates of gymnodimine and 13-desmethyl C spirolide using these solvents were 90.6+/-7.8% and 89.6+/-3.2%, respectively with variations among species. The quantification range of this fluorescence polarization assay for gymnodimine and 13-desmethyl C spirolide in all tested species was 80-2000 microg kg(-1) and 85-700 microg kg(-1) of shellfish meat, respectively. This assay format can be used to detect gymnodimine and 13-desmethyl C spirolide in shellfish as a screening assay. PMID:19951760

  5. Determination of essential elements (copper, manganese, selenium and zinc) in fish and shellfish samples. Risk and nutritional assessment and mercury-selenium balance.

    PubMed

    Olmedo, P; Hernández, A F; Pla, A; Femia, P; Navas-Acien, A; Gil, F

    2013-12-01

    Fish and shellfish are an important source not only of toxic heavy metals, but also of essential elements in the diet. In this study, levels of Cu, Mn, Se and Zn have been determined in fresh, canned and frozen fish and shellfish products. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for essential elements content. The potential human health risks for the consumers and the nutritional value of the products analyzed were assessed. Furthermore, the mercury-selenium ratios and the selenium health benefit value (Se-HBVs) were calculated. The highest concentrations of Cu were found in crustaceans species (shrimp and prawn) as they have hemocyanin (a copper-containing protein) that functions as an oxygen-transport molecule. Mn levels were higher in canned bivalve molluscs, such as cockle and clam, and in fresh common sole. Concerning Se, two fresh predatory fish species (tuna and swordfish) presented the most remarkable concentrations of this element. The highest concentration of the essential metals analysed was found for Zn, especially in fresh and canned mussels. All the species analyzed showed beneficial Hg:Se ratios and Se-HBVs, except for the shark species (blue shark and cat shark) and gilt-head bream because of their high Hg levels and low Se content, respectively. Nevertheless, the biomagnification usually observed in hazardous metals such as Hg would not occur for the essential elements measured in predatory species. The estimated daily intakes of the elements studied represented very low percentages of their reference values, ranging from 0.1% (Se) to 3.9% (Cu) for person weighting 60 kg, so the intake of these elements through fish and shellfish would not pose any risk for the average consumer. Moreover, the contribution of fish and shellfish products to the recommended daily allowances and adequate intakes of these mineral elements ranges from 2.5% (Mn) to 25.4% (Se). PMID

  6. The occurrence of paralytic shellfish toxins in two species of xanthid crab from Suva barrier reef, Fiji Islands.

    PubMed

    Raj, U; Haq, H; Oshima, Y; Yasumoto, T

    1983-01-01

    Five species of crabs commonly occurring on Suva barrier reef, Fiji Islands, were tested for the presence of paralytic shellfish toxins. All 35 specimens of Atergatis floridus and all 18 specimens of Zosimus aeneus tested were lethal to mice, whilst none of 12 specimens of Carpilius maculatus, 8 of C. convexus and 10 of Eriphia sebana tested were lethal. A. floridus contained saxitoxin (55--60%), neosaxitoxin (35--40%), gonyautoxin-II (less than 5%) and a new toxin previously found in a toxic dinoflagellate, Pyrodinium bahamense var. compressa, and tentatively coded PBT (1%). Z. aeneus contained the same components, with additional trace amounts of gonyautoxin-I and III, but neosaxitoxin was the major component in this species. Comparison with the results of testing Okinawan specimens of Z. aeneus, A. floridus and Platipodia granulosa suggests that the toxin profile is specific to species. PMID:6623494

  7. Absolute Quantification of Lipophilic Shellfish Toxins by Quantitative Nuclear Magnetic Resonance Using Removable Internal Reference Substance with SI Traceability.

    PubMed

    Kato, Tsuyoshi; Saito, Maki; Nagae, Mika; Fujita, Kazuhiro; Watai, Masatoshi; Igarashi, Tomoji; Yasumoto, Takeshi; Inagaki, Minoru

    2016-01-01

    Okadaic acid (OA), a lipophilic shellfish toxin, was accurately quantified using quantitative nuclear magnetic resonance with internal standards for the development of an authentic reference standard. Pyridine and the residual proton in methanol-d4 were used as removable internal standards to limit any contamination. They were calibrated based on a maleic acid certified reference material. Thus, the concentration of OA was traceable to the SI units through accurate quantitative NMR with an internal reference substance. Signals from the protons on the oxygenated and unsaturated carbons of OA were used for quantification. A reasonable accuracy was obtained by integrating between the lower and upper (13)C satellite signal range when more than 4 mg of OA was used. The best-determined purity was 97.4% (0.16% RSD) when 20 mg of OA was used. Dinophysistoxin-1, a methylated analog of OA having an almost identical spectrum, was also quantified by using the same methodology. PMID:27396652

  8. Validation of a confirmatory method for lipophilic marine toxins in shellfish using UHPLC-HR-Orbitrap MS.

    PubMed

    Orellana, Gabriel; Vanden Bussche, Julie; Van Meulebroek, Lieven; Vandegehuchte, Michiel; Janssen, Colin; Vanhaecke, Lynn

    2014-09-01

    Lipophilic marine toxins are produced by harmful microalgae and can accumulate in edible filter feeders such as shellfish, leading to an introduction of toxins into the human food chain, causing different poisoning effects. During the last years, analytical methods, based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), have been consolidated by interlaboratory validations. However, the main drawback of LC-MS/MS methods remains the limited number of compounds that can be analyzed in a single run. Due to the targeted nature of these methods, only known toxins, previously considered during method optimization, will be detected. Therefore in this study, a method based on ultra-high-performance liquid chromatography coupled to high-resolution Orbitrap mass spectrometry (UHPLC-HR-Orbitrap MS) was developed. Its quantitative performance was evaluated for confirmatory analysis of regulated lipophilic marine toxins in shellfish flesh according to Commission Decision 2002/657/EC. Okadaic acid (OA), dinophysistoxin-1 (DTX-1), pectenotoxin-2 (PTX-2), azaspiracid-1 (AZA-1), yessotoxin (YTX), and 13-desmethyl spirolide C (SPX-1) were quantified using matrix-matched calibration curves (MMS). For all compounds, the reproducibility ranged from 2.9 to 4.9 %, repeatability from 2.9 to 4.9 %, and recoveries from 82.9 to 113 % at the three different spiked levels. In addition, confirmatory identification of the compounds was effectively performed by the presence of a second diagnostic ion ((13)C). In conclusion, UHPLC-HR-Orbitrap MS permitted more accurate and faster detection of the target toxins than previously described LC-MS/MS methods. Furthermore, HRMS allows to retrospectively screen for many analogues and metabolites using its full-scan capabilities but also untargeted screening through the use of metabolomics software. PMID:24939136

  9. Quantitative Determination of Fatty Acids in Marine Fish and Shellfish from Warm Water of Straits of Malacca for Nutraceutical Purposes

    PubMed Central

    Abd Aziz, Nurnadia; Azlan, Azrina; Ismail, Amin; Mohd Alinafiah, Suryati; Razman, Muhammad Rizal

    2013-01-01

    This study was conducted to quantitatively determine the fatty acid contents of 20 species of marine fish and four species of shellfish from Straits of Malacca. Most samples contained fairly high amounts of polyunsaturated fatty acids (PUFAs), especially alpha-linolenic acid (ALA, C18:3 n3), eicosapentaenoic acid (EPA, C20:5 n3), and docosahexaenoic acid (DHA, C22:6 n3). Longtail shad, yellowstripe scad, and moonfish contained significantly higher (P < 0.05) amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), respectively. Meanwhile, fringescale sardinella, malabar red snapper, black pomfret, Japanese threadfin bream, giant seaperch, and sixbar grouper showed considerably high content (537.2–944.1 mg/100g wet sample) of desirable omega-3 fatty acids. The polyunsaturated-fatty-acids/saturated-fatty-acids (P/S) ratios for most samples were higher than that of Menhaden oil (P/S = 0.58), a recommended PUFA supplement which may help to lower blood pressure. Yellowstripe scad (highest DHA, ω − 3/ω − 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ω − 3/ω − 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ω − 3/ω − 6 = 0.8, P/S = 0.4) were the samples with an outstandingly desirable overall composition of fatty acids. Overall, the marine fish and shellfish from the area contained good composition of fatty acids which offer health benefits and may be used for nutraceutical purposes in the future. PMID:23509703

  10. Distribution of heavy metals in internal organs and tissues of Korean molluscan shellfish and potential risk to human health.

    PubMed

    Mok, Jong Soo; Kwon, Ji Young; Son, Kwang Tae; Choi, Woo Seok; Kim, Poong Ho; Lee, Tae Seek; Kim, Ji Hoe

    2015-09-01

    Molluscan shellfish (gastropods and bivalves) were collected from major fish markets on the Korean coast and analyzed for mercury by direct Hg analyzer and for other metals, such as cadmium, lead, chromium, silver, nickel, copper and zinc, using inductively coupled plasma mass spectrometry. Distribution of heavy metals in muscles, internal organs and whole tissues were determined and a potential risk assessment was conducted to evaluate their hazard for human consumption. Heavy metals were accumulated significantly higher (P < 0.05) in internal organs than in muscles for all species. The mean Cd level, which had the highest level of three hazardous metals (Cd, Pb, and Hg) in all internal-organ samples were above the regulatory limit of Korea and the mean level in whole tissue samples of the selected gastropod species, bay scallop and comb pen shell, exceeded the limit (except in a few cases). The sum of the estimated dietary intake of Cd, Pb and Hg for each part of all tested species accounted for 1.59-16.94, 0.02-0.36, and 0.07-0.16% respectively, of the provisional tolerable daily intake adopted by the Joint FAO/WHO Expert Committee on Food Additives. The hazard index for each part of gastropods and bivalves was below 1.0, however, the maximum HI for internal organs of all analysed species was quite high (0.71). These results suggest that consumption of flesh after removing the internal organs of some molluscan shellfish (all gastropod species, bay scallop and comb pen shell) is a suitable way for reducing Cd exposure. PMID:26521561

  11. Quantitative determination of fatty acids in marine fish and shellfish from warm water of Straits of Malacca for nutraceutical purposes.

    PubMed

    Abd Aziz, Nurnadia; Azlan, Azrina; Ismail, Amin; Mohd Alinafiah, Suryati; Razman, Muhammad Rizal

    2013-01-01

    This study was conducted to quantitatively determine the fatty acid contents of 20 species of marine fish and four species of shellfish from Straits of Malacca. Most samples contained fairly high amounts of polyunsaturated fatty acids (PUFAs), especially alpha-linolenic acid (ALA, C18:3 n3), eicosapentaenoic acid (EPA, C20:5 n3), and docosahexaenoic acid (DHA, C22:6 n3). Longtail shad, yellowstripe scad, and moonfish contained significantly higher (P < 0.05) amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), respectively. Meanwhile, fringescale sardinella, malabar red snapper, black pomfret, Japanese threadfin bream, giant seaperch, and sixbar grouper showed considerably high content (537.2-944.1 mg/100 g wet sample) of desirable omega-3 fatty acids. The polyunsaturated-fatty-acids/saturated-fatty-acids (P/S) ratios for most samples were higher than that of Menhaden oil (P/S = 0.58), a recommended PUFA supplement which may help to lower blood pressure. Yellowstripe scad (highest DHA, ω - 3/ω - 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ω - 3/ω - 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ω - 3/ω - 6 = 0.8, P/S = 0.4) were the samples with an outstandingly desirable overall composition of fatty acids. Overall, the marine fish and shellfish from the area contained good composition of fatty acids which offer health benefits and may be used for nutraceutical purposes in the future. PMID:23509703

  12. Predator-prey interactions between blue crabs and ribbed mussels living in clumps

    NASA Astrophysics Data System (ADS)

    Lin, Junda

    1991-01-01

    Predator-prey interactions between blue crabs ( Callinectes sapidus) and ribbed mussels ( Geukensia demissa) were studied by manipulating different components of mussel clump structure in the laboratory to test their effects on the mussels' susceptibility to crab predation. Mussels with stronger attachment strength or those buried deeper in the sediment suffered lower mortality. Blue crabs showed no significant size selectivity when two size classes of mussles (30-40 and 50-60 mm in shell heights) were offered. When juvenile mussels were attached to adult conspecifics and completely buried in the centres of clumps as in the field, blue crabs did not actively search for them. The crabs, however, did consume juveniles as by-products when they preyed upon the adult mussels to which the juveniles were attached.

  13. Bacteriological quality evaluation of seawater and oysters from the Jaranman-Saryangdo area, a designated shellfish growing area in Korea: Impact of inland pollution sources.

    PubMed

    Mok, Jong Soo; Lee, Ka Jeong; Kim, Poong Ho; Lee, Tae Seek; Lee, Hee Jung; Jung, Yeoun Joong; Kim, Ji Hoe

    2016-07-15

    From 2011 to 2013, we conducted a full sanitary survey of pollution sources in proximity to a designated shellfish growing area in Korea, and their impact on the sea area therein. From this area, 836 seawater samples and 93 oyster samples were examined to evaluate their bacteriological quality. There were 483 potential pollution sources in the drainage area of the Jaranman-Saryangdo area, including 38 sources discharging water. It demonstrates that while many pollution sources have been identified, no significant impact occurred within the designated shellfish growing area. Variations in fecal coliform (FC) levels in seawater were closely related to rainfall. The FC levels of seawater and oysters from the designated area met the regulation limits set by various countries. Our study indicates that the oysters produced in this area are apparently safe for raw consumption based on their bacterial quality. PMID:27113023

  14. Metal bioaccumulation and physiological condition of the Pacific oyster (Crassostrea gigas) reared in two shellfish basins and a marina in Normandy (northwest France).

    PubMed

    Séguin, A; Caplat, C; Serpentini, A; Lebel, J M; Menet-Nedelec, F; Costil, K

    2016-05-15

    A 5-month experiment combining a geochemical survey of metals with a bioaccumulation study in batches of Crassostrea gigas was conducted in two shellfish farming areas and a marina in Normandy (France). Various endpoints at different levels of biological organization were studied. ROCCH data showed differences in biota contamination between the two shellfish areas but the present study revealed only slight differences in metallic contamination and biomarkers. By contrast, significantly different values were recorded in the marina in comparison with the two other sites. Indeed, higher levels of Cd, Cu and Zn were measured in the oysters from the marina, and these oysters also showed a poorer physiological condition (e.g., condition index, histopathological alterations and neutral lipid content). For coastal monitoring, the multi-biomarker approach coupled with an assessment of metallic contamination in biota appeared to be suitable for discriminating spatial differences in environmental quality after only a few months of exposure. PMID:26975610

  15. First Detection of Tetrodotoxin in Greek Shellfish by UPLC-MS/MS Potentially Linked to the Presence of the Dinoflagellate Prorocentrum minimum.

    PubMed

    Vlamis, Aristidis; Katikou, Panagiota; Rodriguez, Ines; Rey, Verónica; Alfonso, Amparo; Papazachariou, Angelos; Zacharaki, Thetis; Botana, Ana M; Botana, Luis M

    2015-05-01

    During official shellfish control for the presence of marine biotoxins in Greece in year 2012, a series of unexplained positive mouse bioassays (MBA) for lipophilic toxins with nervous symptomatology prior to mice death was observed in mussels from Vistonikos Bay-Lagos, Rodopi. This atypical toxicity coincided with (a) absence or low levels of regulated and some non-regulated toxins in mussels and (b) the simultaneous presence of the potentially toxic microalgal species Prorocentrum minimum at levels up to 1.89 × 103 cells/L in the area's seawater. Further analyses by different MBA protocols indicated that the unknown toxin was hydrophilic, whereas UPLC-MS/MS analyses revealed the presence of tetrodotoxins (TTXs) at levels up to 222.9 μg/kg. Reviewing of official control data from previous years (2006-2012) identified a number of sample cases with atypical positive to asymptomatic negative MBAs for lipophilic toxins in different Greek production areas, coinciding with periods of P. minimum blooms. UPLC-MS/MS analysis of retained sub-samples from these cases revealed that TTXs were already present in Greek shellfish since 2006, in concentrations ranging between 61.0 and 194.7 μg/kg. To our knowledge, this is the earliest reported detection of TTXs in European bivalve shellfish, while it is also the first work to indicate a possible link between presence of the toxic dinoflagellate P. minimum in seawater and that of TTXs in bivalves. Confirmed presence of TTX, a very heat-stable toxin, in filter-feeding mollusks of the Mediterranean Sea, even at lower levels to those inducing symptomatology to humans, indicates that this emerging risk should be seriously taken into account by the EU to protect the health of shellfish consumers. PMID:26008234

  16. First Detection of Tetrodotoxin in Greek Shellfish by UPLC-MS/MS Potentially Linked to the Presence of the Dinoflagellate Prorocentrum minimum

    PubMed Central

    Vlamis, Aristidis; Katikou, Panagiota; Rodriguez, Ines; Rey, Verónica; Alfonso, Amparo; Papazachariou, Angelos; Zacharaki, Thetis; Botana, Ana M.; Botana, Luis M.

    2015-01-01

    During official shellfish control for the presence of marine biotoxins in Greece in year 2012, a series of unexplained positive mouse bioassays (MBA) for lipophilic toxins with nervous symptomatology prior to mice death was observed in mussels from Vistonikos Bay–Lagos, Rodopi. This atypical toxicity coincided with (a) absence or low levels of regulated and some non-regulated toxins in mussels and (b) the simultaneous presence of the potentially toxic microalgal species Prorocentrum minimum at levels up to 1.89 × 103 cells/L in the area’s seawater. Further analyses by different MBA protocols indicated that the unknown toxin was hydrophilic, whereas UPLC-MS/MS analyses revealed the presence of tetrodotoxins (TTXs) at levels up to 222.9 μg/kg. Reviewing of official control data from previous years (2006–2012) identified a number of sample cases with atypical positive to asymptomatic negative MBAs for lipophilic toxins in different Greek production areas, coinciding with periods of P. minimum blooms. UPLC-MS/MS analysis of retained sub-samples from these cases revealed that TTXs were already present in Greek shellfish since 2006, in concentrations ranging between 61.0 and 194.7 μg/kg. To our knowledge, this is the earliest reported detection of TTXs in European bivalve shellfish, while it is also the first work to indicate a possible link between presence of the toxic dinoflagellate P. minimum in seawater and that of TTXs in bivalves. Confirmed presence of TTX, a very heat-stable toxin, in filter-feeding mollusks of the Mediterranean Sea, even at lower levels to those inducing symptomatology to humans, indicates that this emerging risk should be seriously taken into account by the EU to protect the health of shellfish consumers. PMID:26008234

  17. Application of next-generation sequencing to investigation of norovirus diversity in shellfish collected from two coastal sites in Japan from 2013 to 2014.

    PubMed

    Imamura, Saiki; Haruna, Mika; Goshima, Tomoko; Kanezashi, Hiromi; Okada, Tsukasa; Akimoto, Keiko

    2016-05-01

    A better understanding of the role played by shellfish regarding the manner of pathogen contamination, persistence, and selection may help considering epidemiology of noroviruses. Thus, norovirus genotype profiles in shellfish (Crassostrea gigas and Mitilus galloprovincialis) were investigated by using Next-generation sequencing (NGS) technology. In genogroup I (GI), 7 genotypes (abbreviated as GI.2 to GI.7, and GI.9) were detected from C. gigas, whereas 9 genotypes (GI.1 to GI.9) were detected from M. galloprovincialis. The genotype with the highest proportion found in both C. gigas and M. galloprovincialis was GI.4, and the second highest was GI.3. In genogroup II (GII), 17 genotypes (GII.1 to GII.9, GII.11 to GII.17, GII.21 and GI.22) were detected from C. gigas, whereas 16 genotypes (GII.1 to GII.8, GII.11 to GII.17, GII.21 and GI.22) were detected from M. galloprovincialis. The genotype with the highest proportion in both C. gigas and M. galloprovincialis was GII.4, the next highest differed between C. gigas and M. galloprovincialis. To our knowledge, this study may be the first trial to utilize the latest technology in this field, and reveal the diversity of norovirus genotypes present in shellfish. PMID:27506085

  18. Comparison of two rapid test procedures with the standard EC test recovery of fecal coliform bacteria from shellfish-growing waters.

    PubMed

    Hunt, D A; Springer, J

    1978-11-01

    A study was conducted to compare recovery and enumeration capability of two 24-hr multitube fermentation tests with the standard EC test for fecal coliform levels in shellfish-growing waters. The 2 tests were the A-1 test developed by Andrews and Presnell, specifying 24-hr incubation in A-1 medium at 44.5 degree C; and a modification of the A-1 test requiring a 3-hr resuscitation of 35 degree C before incubation at 44.5 degree C for 21 hr. Fifteen State, Federal, and Provincial laboratories examined 10 routine shellfish-growing area samples per month in parallel by the 3 methods for 1 year. IMViC tests (indole, methyl red, Voges-Proskauer, and citrate) were conducted on all gas-positive tubes. The modified A-1 test recovered higher levels of fecal coliforms than the A-1 test. Although there were seasonal and geographic variations in recovery and enumeration by the modified A-1 test, overall there was good correlation of the modified A-1 test with the EC test. Both the A-1 and modified A-1 tests were more specific for Escherichia coli than the EC test. Results of the study indicate that the 24-hr modified A-1 test can be used as an alterantive test for the standard 72-hr EC test as an adjunct to the sanitary survey for the classification and control of shellfish-growing areas waters. PMID:365853

  19. Rapid liquid chromatography for paralytic shellfish toxin analysis using superficially porous chromatography with AOAC Official Method 2005.06.

    PubMed

    Hatfield, Robert G; Turner, Andrew D

    2012-01-01

    The bioaccumulation of paralytic shellfish toxins in mussels, oysters, cockles, hard clams, razors, and king scallops is monitored in England, Scotland, and Wales by AOAC Official Method 2005.06 LC-with fluorescence detection (FLD). One of the commonly perceived disadvantages of using this method is the long turnaround time and low throughput in a busy laboratory environment. The chromatographic analysis of each sample typically utilizes a 15 min cycle time to achieve toxin oxidation product separation and column equilibration prior to subsequent analysis. A standard RP C18 analytical column, used successfully in recent years, achieves good separation with a long column lifetime. The analysis of a 40 sample qualitative screening batch takes approximately 18 h, including blanks, standards, and other QC samples. The availability of superficially porous column technology has offered the potential to reduce analysis time while retaining column performance on existing hardware. In this study, AOAC Official Method 2005.06 with LC-FLD was transferred to two different commercially available superficially porous columns, and the method performance characteristics were evaluated. Both columns separated all toxins adequately with cycle times less than half that of the existing method. Linearity for each toxin was acceptable up to two times the European maximum permitted limit of 800 microg di-HCl saxitoxin equivalent/kg flesh. LOD and LOQ values were substantially improved for the majority of toxins, with gonyautoxin 1&4 and neosaxitoxin showing up to a two- and fourfold improvement, respectively, depending on the column used. Quantification results obtained from parallel analysis of contaminated samples were acceptable on both columns. Comparative screen results gave a slight increase in the occurrence of contaminated samples, which was attributed to the improved detection limit for most toxins. Issues with rapidly increasing back pressure, however, were identified with both

  20. Stanols as a tool to track the origin of microbial contamination of oysters, Crassostrea gigas, in shellfish areas.

    NASA Astrophysics Data System (ADS)

    Harrault, Loïc; Jardé, Emilie; Jeanneau, Laurent; Petitjean, Patrice

    2013-04-01

    Runoff of cattle manures (cows, pigs, sheeps) or discharge of effluent from wastewater treatment plants (WWTP) into aquatic ecosystems can lead to microbiological contamination of waters and living organisms. In coastal ecosystems and particularly in shellfish harvesting areas, the presence of pathogen microorganisms in waters induces fecal contamination of filter feeding bivalves (oysters, mussels, scallops…), therefore leading to human health risks associated to the consumption of these contaminated organisms. Watershed management plans that aim at limiting these risks require the development of tools able to identify fecal contamination sources. The fecal indicator bacteria used in the regulations to determine fecal contamination are not source specific since they are found in the feces of most warm-blooded animals. Thus, microbiological biomarkers have been developed in association with chemical biomarkers as Microbial Source Tracking (MST) methods. Fecal stanols, by-products of sterols obtained by human and animal microbial gut flora, are found in considerable amounts in feces with different relative proportions depending on their animal or human source. Recently, in association with microbiological biomarkers, the stanol fingerprint of contaminated waters has been successfully used to determine the main source of fecal contamination (cow, pig or human sources) in rural watersheds (Brittany, France). Up to now, the use of the stanol fingerprint to track the fecal contamination in shellfish tissues, especially bivalves, has been limited to the analysis of coprostanol, a stanol commonly associated to human contamination. Therefore, whether the stanol fingerprint can be used as a MST method in bivalves or not is still unknown. The first aim of this study was to compare several organic extraction procedures of stanols in the oyster Crassostrea gigas to determine a reliable method for stanol fingerprint analysis in bivalves. Solvent extraction and purification

  1. Transformation of paralytic shellfish poisoning toxins in UK surf clams (Spisula solida) for targeted production of reference materials.

    PubMed

    Turner, Andrew D; Lewis, Adam M; O'Neil, Alison; Hatfield, Robert G

    2013-04-01

    The periodic occurrence of Paralytic Shellfish Poisoning (PSP) toxins in UK surf clams and the recent move away from biological assays for PSP testing resulted in the need to determine method performance characteristics for the replacement analytical method in this species. With the requirement for laboratory reference materials to aid this validation together with known issues relating to toxin transformation in live clams and homogenised tissue, there was the need to assess the toxin transformation characteristics of PSP toxins in surf clam tissue. Initial work examined the rates of toxin transformation in UK surf clam tissue incubated with toxin standards, showing rapid transformation of N-sulfocarbamoyl toxins with slower transformation of carbamate toxins. Full transformational pathways were determined using a combination of three different analytical methods and confirmed the major expected transformations involving decarbamoylation, with some evidence for additional reaction pathways. Results obtained from the analysis of surf clam and oyster tissues incubated with varying concentrations of toxic Alexandrium algae highlighted expected transformation reactions, although significant differences were observed in the extent of the transformations amongst the range of toxins studied, with less efficient transformation of N-hydroxylated toxins as compared with other carbamate and N-sulfocarbamoyl toxins. Analysis of PSP-toxic incurred oyster, scallop and mussel tissues incubated with variable proportions of surf clam tissue showed large differences in the extent of the transformations. Total conversion of N-sulfocarbamoyl toxins was confirmed at low relative proportions of surf clam tissue in all three species, whereas transformation of carbamate toxins was found to occur only in the presence of higher proportions of surf clam tissue in oysters and mussels in comparison with scallops. Results enabled the production of three laboratory reference materials prepared

  2. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary.

    PubMed

    Mafra, Luiz L; Lopes, Daiana; Bonilauri, Vanessa C; Uchida, Hajime; Suzuki, Toshiyuki

    2015-06-01

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L-1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L-1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg-1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. PMID:26096277

  3. Exposure to the Paralytic Shellfish Toxin Producer Alexandrium catenella Increases the Susceptibility of the Oyster Crassostrea gigas to Pathogenic Vibrios.

    PubMed

    Abi-Khalil, Celina; Lopez-Joven, Carmen; Abadie, Eric; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-Luc

    2016-01-01

    The multifactorial etiology of massive Crassostrea gigas summer mortalities results from complex interactions between oysters, opportunistic pathogens and environmental factors. In a field survey conducted in 2014 in the Mediterranean Thau Lagoon (France), we evidenced that the development of the toxic dinoflagellate Alexandrium catenella, which produces paralytic shellfish toxins (PSTs), was concomitant with the accumulation of PSTs in oyster flesh and the occurrence of C. gigas mortalities. In order to investigate the possible role of toxic algae in this complex disease, we experimentally infected C. gigas oyster juveniles with Vibrio tasmaniensis strain LGP32, a strain associated with oyster summer mortalities, after oysters were exposed to Alexandrium catenella. Exposure of oysters to A. catenella significantly increased the susceptibility of oysters to V. tasmaniensis LGP32. On the contrary, exposure to the non-toxic dinoflagellate Alexandrium tamarense or to the haptophyte Tisochrysis lutea used as a foraging alga did not increase susceptibility to V. tasmaniensis LGP32. This study shows for the first time that A. catenella increases the susceptibility of Crassostrea gigas to pathogenic vibrios. Therefore, in addition to complex environmental factors explaining the mass mortalities of bivalve mollusks, feeding on neurotoxic dinoflagellates should now be considered as an environmental factor that potentially increases the severity of oyster mortality events. PMID:26784228

  4. Occurrence of paralytic shellfish poison (PSP) in the starfish Asterina pectinifera collected from the Kure Bay, Hiroshima Prefecture, Japan.

    PubMed

    Ito, Katsutoshi; Asakawa, Manabu; Sida, Yasuo; Miyazawa, Keisuke

    2003-03-01

    Assays were made for paralytic toxicity of marine invertebrates inhabiting at the coasts of Hiroshima Bay, where the infestation of bivalves such as cultured oysters with paralytic shellfish poison (PSP) has been occurred. The starfish Asterina pectinifera collected at the estuary of Nikoh River, Hiroshima Bay, was found to contain moderate levels of paralytic toxicity. Its highest toxicities as PSP found on July 30, 1999 were 12.5 MU/g for whole body, 11.0 MU/g for integument tissues and 3.9 MU/g for viscera, respectively. The toxicity of integument was changed from 3.6 to 11.0 MU/g in 1 year. Its paralytic toxin principles were identified as PSP toxins, composing mainly from saxitoxin (STX) group toxins such as carbamoyl-N-hydroxy neosaxitoxin (hyneoSTX), and STX, by HPLC and LC-MS, accounting for over 90 mol%. The PSP toxins contained in the starfish A. pectinifera considered to be transferred from bivalves or detritus living in the same area, which were contaminated with PSP. However, the involved pathway may be different from that of Asterias amurensis which was infested directly through food chain from its food bivalves, for its toxin pattern. PMID:12565751

  5. Prevalence of human pathogenic enteric viruses in bivalve molluscan shellfish and cultured shrimp in south west coast of India.

    PubMed

    Umesha, Kanasinakatte R; Bhavani, Naniah C; Venugopal, Moleyur N; Karunasagar, Indrani; Krohne, Georg; Karunasagar, Iddya

    2008-03-20

    The prevalence of human enteric viruses in bivalve molluscan shellfish and shrimp collected off the south west coast of India was studied to assess the extent of fecal pollution of coastal environment. Out of 194 samples analyzed, 37% of oyster, 46% of clam and 15% of shrimp samples were positive for enteroviruses (EV). Adenoviruses (ADV) were detected in 17% of oyster and 27% of clam samples. However, other enteric viruses such as noroviruses (NoV) and hepatitis A virus (HAV) were not detected in any of the samples. High prevalence of EV and ADV was noticed between May to December. Thirty four percent of oyster and 49% of clam samples showed fecal coliform values higher than the limit. MS-2 phage was detected in 57% of oyster and 73% of clam samples. The presence of MS-2 phage and human enteric viruses showed association while fecal coliforms and enteric viruses showed no association. However, 17 samples, which were positive for enteric viruses (EV and ADV), were negative for MS-2 phage. PMID:18279989

  6. Effects of low carbohydrate diets high in red meats or poultry, fish and shellfish on plasma lipids and weight loss

    PubMed Central

    Cassady, Bridget A; Charboneau, Nicole L; Brys, Emily E; Crouse, Kristin A; Beitz, Donald C; Wilson, Ted

    2007-01-01

    Background Low carbohydrate diets (LCDs) have been demonstrated to be effective tools for promoting weight loss and an improved plasma lipid profile. Such diets are often associated with increased meat consumption, either poultry, fish, and shellfish (PFS), which are generally high in polyunsaturated fat (PUFA) or red meats (RM), generally high in saturated fat (SFA). The fatty acid profile and content of a diet may influence the plasma lipid profile of humans. This study examined whether the type of meat consumed could influence the outcome of an LCD. Methods Moderately obese subjects consumed two different LCDs as part of a weight loss regimen: 1) a diet high in foods of mammalian origin (RM) intended to contain more SFA, or 2) a diet high in PFS intended to contain more PUFA. Diet dependent changes in body weight, nutritional intake, and plasma lipids were evaluated during a 28 day study period. Results Both diets were associated with significant weight loss after 28 days, -5.26 ± 0.84 kg and -5.74 ± 0.63 kg for RM and PFS groups, respectively. The PFS diet was associated with a significantly higher intake of PUFA and cholesterol. Despite high cholesterol and fat intakes, neither diet was associated with significant changes in plasma cholesterol or the plasma lipoprotein cholesterol profile. While plasma triglycerides were reduced in both groups, the effect was only statistically significant for the PFS diet. PMID:17974023

  7. The sxt Gene and Paralytic Shellfish Poisoning Toxins as Markers for the Monitoring of Toxic Alexandrium Species Blooms.

    PubMed

    Penna, Antonella; Perini, Federico; Dell'Aversano, Carmela; Capellacci, Samuela; Tartaglione, Luciana; Giacobbe, Maria Grazia; Casabianca, Silvia; Fraga, Santiago; Ciminiello, Patrizia; Scardi, Michele

    2015-12-15

    Paralytic shellfish poisoning (PSP) is a serious human illness caused by the ingestion of seafood contaminated with saxitoxin and its derivatives (STXs). These toxins are produced by some species of marine dinoflagellates within the genus Alexandrium. In the Mediterranean Sea, toxic Alexandrium spp. blooms, especially of A. minutum, are frequent and intense with negative impact to coastal ecosystem, aquaculture practices and other economic activities. We conducted a large scale study on the sxt gene and toxin distribution and content in toxic dinoflagellate A. minutum of the Mediterranean Sea using both quantitative PCR (qPCR) and HILIC-HRMS techniques. We developed a new qPCR assay for the estimation of the sxtA1 gene copy number in seawater samples during a bloom event in Syracuse Bay (Mediterranean Sea) with an analytical sensitivity of 2.0 × 10° sxtA1 gene copy number per reaction. The linear correlation between sxtA1 gene copy number and microalgal abundance and between the sxtA1 gene and STX content allowed us to rapidly determine the STX-producing cell concentrations of two Alexandrium species in environmental samples. In these samples, the amount of sxtA1 gene was in the range of 1.38 × 10(5) - 2.55 × 10(8) copies/L and the STX concentrations ranged from 41-201 nmol/L. This study described a potential PSP scenario in the Mediterranean Sea. PMID:26580419

  8. Analysis of paralytic shellfish toxins, potential chemical threat agents, in food using hydrophilic interaction liquid chromatography-mass spectrometry.

    PubMed

    Jansson, Daniel; Åstot, Crister

    2015-10-23

    A novel method for determining paralytic shellfish toxin (PST) profiles in food was developed using a combination of silica and strong cation exchange (SCX) solid phase extraction (SPE) coupled to hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS). Besides the risk for natural contamination of seafood and drinking water, PSTs also pose potent threats through intentional contamination of food, due to their high toxicity and the wide distributions of toxin-producing algae. The new preparation method aim to maintain the samples' original toxin profiles by avoiding conditions known to induce interconversion or degradation of the PSTs. The method was evaluated for PST extraction from water, milk, orange juice, apple purée, baby food, and blue mussels (Mytilus edulis). The extracts were found to produce reproducible retention times in HILIC-MS/MS analysis. When an authentic toxic mussel sample was analyzed using the novel method, saxitoxin and gonyautoxin-3 were identified, in agreement with data acquired using the Lawrence pre-column oxidation high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method. Overall recoveries of the PSTs from tested foods by the novel method ranged from 36% to 111%. PMID:26404910

  9. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary

    PubMed Central

    Mafra, Luiz L.; Lopes, Daiana; Bonilauri, Vanessa C.; Uchida, Hajime; Suzuki, Toshiyuki

    2015-01-01

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L−1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L−1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg−1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. PMID:26096277

  10. Exposure to the Paralytic Shellfish Toxin Producer Alexandrium catenella Increases the Susceptibility of the Oyster Crassostrea gigas to Pathogenic Vibrios

    PubMed Central

    Abi-Khalil, Celina; Lopez-Joven, Carmen; Abadie, Eric; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-Luc

    2016-01-01

    The multifactorial etiology of massive Crassostrea gigas summer mortalities results from complex interactions between oysters, opportunistic pathogens and environmental factors. In a field survey conducted in 2014 in the Mediterranean Thau Lagoon (France), we evidenced that the development of the toxic dinoflagellate Alexandrium catenella, which produces paralytic shellfish toxins (PSTs), was concomitant with the accumulation of PSTs in oyster flesh and the occurrence of C. gigas mortalities. In order to investigate the possible role of toxic algae in this complex disease, we experimentally infected C. gigas oyster juveniles with Vibrio tasmaniensis strain LGP32, a strain associated with oyster summer mortalities, after oysters were exposed to Alexandrium catenella. Exposure of oysters to A. catenella significantly increased the susceptibility of oysters to V. tasmaniensis LGP32. On the contrary, exposure to the non-toxic dinoflagellate Alexandrium tamarense or to the haptophyte Tisochrysis lutea used as a foraging alga did not increase susceptibility to V. tasmaniensis LGP32. This study shows for the first time that A. catenella increases the susceptibility of Crassostrea gigas to pathogenic vibrios. Therefore, in addition to complex environmental factors explaining the mass mortalities of bivalve mollusks, feeding on neurotoxic dinoflagellates should now be considered as an environmental factor that potentially increases the severity of oyster mortality events. PMID:26784228

  11. Influence of body weight of mice on the susceptibility to okadaic acid, a diarrhetic shellfish poisoning toxin.

    PubMed

    Suzuki, Hodaka

    2014-04-01

    The mouse bioassay (MBA) for diarrhetic shellfish poisoning (DSP) toxins has been widely used in many countries of the world. However, different body weight ranges of mice are designated to be used in the Japanese official method and European Union procedure. In this study we investigated whether and to what extent the body weights of the mice affect the susceptibility to DSP toxins. A lethal dose of okadaic acid, one of the representative DSP toxins, was injected intraperitoneally into mice of five different body weight range groups, from 14 to 24 g. The mice were observed until 24 h after injection. The lethality was 100% in the 14-15 and 16-17 g groups, 80% in the 19-20 g group, 50% in the 21-22 g group, and 40% in the 23-24 g group, with significant differences. Survival analysis indicated a relationship between body weights of mice and susceptibility to okadaic acid. These results would be quite useful not only for the MBA, but also to improve understanding of the biological responses to DSP toxins. PMID:24460779

  12. Graphene based pipette tip solid phase extraction of marine toxins in shellfish muscle followed by UPLC-MS/MS analysis.

    PubMed

    Shen, Qing; Gong, Like; Baibado, Joewel T; Dong, Wei; Wang, Yixuan; Dai, Zhiyuan; Cheung, Hon-Yeung

    2013-11-15

    Graphene is a novel carbonic material with great potentials for the use as sorbent due to its ultrahigh surface area. Herein, we report the use of graphene as sorbent in solid-phase extraction (SPE) using pipette tip as cartridge namely GPT-SPE, together with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), for the analysis of lipophilic marine toxins (LMTs), including yessotoxins (YTX), okadaic acid (OA), dinophysistoxin-1 (DTX1), gymnodimine (GYM), spirolides-1 (SPX1), pectenotoxin-2 (PTX2) and azaspiracid-1 (AZA1) in shellfish. The GPT-SPE procedure was optimized and the performance of graphene was fully validated. Results with high-sensitivity and good reproducibility was obtained and compared with that of other sorbents like C18 silica, multi-walled carbon nanotubes (MWCNTs), commercial Oasis HLB, and Strata-X for the extraction of LMTs, which showed superiority and advantages of graphene, such as good recoveries, stability and compatibility with various solvents. In order to exhibit the potentials of graphene as an excellent sorbent material, 67 mussel samples from six coastal cities of China were analyzed. OA was found to be the dominant contaminant, while YTX was also detected with low level. PMID:24148472

  13. Future Oceanic Warming and Acidification Alter Immune Response and Disease Status in a Commercial Shellfish Species, Mytilus edulis L.

    PubMed Central

    Mackenzie, Clara L.; Lynch, Sharon A.; Culloty, Sarah C.; Malham, Shelagh K.

    2014-01-01

    Increases in atmospheric carbon dioxide are leading to physical changes in marine environments including parallel decreases in ocean pH and increases in seawater temperature. This study examined the impacts of a six month exposure to combined decreased pH and increased temperature on the immune response and disease status in the blue mussel, Mytilus edulis L. Results provide the first confirmation that exposure to future acidification and warming conditions via aquarium-based simulation may have parallel implications for bivalve health. Collectively, the data suggests that temperature more than pH may be the key driver affecting immune response in M. edulis. Data also suggests that both increases in temperature and/or lowered pH conditions may lead to changes in parasite abundance and diversity, pathological conditions, and bacterial incidence in M. edulis. These results have implications for future management of shellfish under a predicted climate change scenario and future sustainability of shellfisheries. Examination of the combined effects of two stressors over an extended exposure period provides key preliminary data and thus, this work represents a unique and vital contribution to current research efforts towards a collective understanding of expected near-future impacts of climate change on marine environments. PMID:24927423

  14. Paralytic shellfish toxin content is related to genomic sxtA4 copy number in Alexandrium minutum strains.

    PubMed

    Stüken, Anke; Riobó, Pilar; Franco, José; Jakobsen, Kjetill S; Guillou, Laure; Figueroa, Rosa I

    2015-01-01

    Dinoflagellates are microscopic aquatic eukaryotes with huge genomes and an unusual cell regulation. For example, most genes are present in numerous copies and all copies seem to be obligatorily transcribed. The consequence of the gene copy number (CPN) for final protein synthesis is, however, not clear. One such gene is sxtA, the starting gene of paralytic shellfish toxin (PST) synthesis. PSTs are small neurotoxic compounds that can accumulate in the food chain and cause serious poisoning incidences when ingested. They are produced by dinoflagellates of the genera Alexandrium, Gymnodium, and Pyrodinium. Here we investigated if the genomic CPN of sxtA4 is related to PST content in Alexandrium minutum cells. SxtA4 is the 4th domain of the sxtA gene and its presence is essential for PST synthesis in dinoflagellates. We used PST and genome size measurements as well as quantitative PCR to analyze sxtA4 CPN and toxin content in 15 A. minutum strains. Our results show a strong positive correlation between the sxtA4 CPN and the total amount of PST produced in actively growing A. minutum cells. This correlation was independent of the toxin profile produced, as long as the strain contained the genomic domains sxtA1 and sxtA4. PMID:25983733

  15. Paralytic shellfish toxin content is related to genomic sxtA4 copy number in Alexandrium minutum strains

    PubMed Central

    Stüken, Anke; Riobó, Pilar; Franco, José; Jakobsen, Kjetill S.; Guillou, Laure; Figueroa, Rosa I.

    2015-01-01

    Dinoflagellates are microscopic aquatic eukaryotes with huge genomes and an unusual cell regulation. For example, most genes are present in numerous copies and all copies seem to be obligatorily transcribed. The consequence of the gene copy number (CPN) for final protein synthesis is, however, not clear. One such gene is sxtA, the starting gene of paralytic shellfish toxin (PST) synthesis. PSTs are small neurotoxic compounds that can accumulate in the food chain and cause serious poisoning incidences when ingested. They are produced by dinoflagellates of the genera Alexandrium, Gymnodium, and Pyrodinium. Here we investigated if the genomic CPN of sxtA4 is related to PST content in Alexandrium minutum cells. SxtA4 is the 4th domain of the sxtA gene and its presence is essential for PST synthesis in dinoflagellates. We used PST and genome size measurements as well as quantitative PCR to analyze sxtA4 CPN and toxin content in 15 A. minutum strains. Our results show a strong positive correlation between the sxtA4 CPN and the total amount of PST produced in actively growing A. minutum cells. This correlation was independent of the toxin profile produced, as long as the strain contained the genomic domains sxtA1 and sxtA4. PMID:25983733

  16. Analysis of paralytic shellfish toxins using high-field asymmetric waveform ion mobility spectrometry with liquid chromatography-mass spectrometry.

    PubMed

    Beach, Daniel G; Melanson, Jeremy E; Purves, Randy W

    2015-03-01

    The analysis of paralytic shellfish toxins (PSTs) by liquid chromatography-mass spectrometry remains a challenge because of their high polarity, large number of analogues and the complex matrix in which they occur. Here we investigate the potential utility of high-field asymmetric waveform ion mobility spectrometry (FAIMS) as a gas-phase ion separation tool for analysis of PSTs by mass spectrometry. We investigate the separation of PSTs using FAIMS with two divergent goals: using FAIMS as a primary separation tool for rapid screening by electrospray ionization (ESI)-FAIMS-MS or combined with LC in a multidimensional LC-ESI-FAIMS-MS separation. First, a survey of the parameters that affect the sensitivity and selectivity of PST analysis by FAIMS was carried out using ESI-FAIMS-MS. In particular, the use of acetonitrile as a gas additive in the carrier gas flow offered good separation of all PST epimeric pairs. A second set of FAIMS conditions was also identified, which focussed PSTs to a relatively narrow CV range allowing development of an LC-ESI-FAIMS-MS method for analysis of PST toxins in complex mussel tissue extracts. The quantitative capabilities of this method were evaluated by analysing a PST containing mussel tissue matrix material. Results compared favourably with analysis by an established LC-post-column oxidation-fluorescence method with recoveries ranging from 70 to 106%, although sensitivity was somewhat reduced. The current work represents the first successful separation of PST isomers using ion mobility and shows the promise of FAIMS as a tool for analysis of algal biotoxins in complex samples and outlines some critical requirements for its future improvement. PMID:25619987

  17. Health-Related Quality of Life among Artisanal Fisherwomen/Shellfish Gatherers: Lower than the General Population

    PubMed Central

    Müller, Juliana dos Santos; Falcão, Ila Rocha; Couto, Maria Carolina Barreto Moreira; Viana, Wendel da Silva; Alves, Ivone Batista; Viola, Denise Nunes; Woods, Courtney Georgette; Rêgo, Rita Franco

    2016-01-01

    Quality of life is an indicator of how well one perceives that he/she is functioning physically and mentally. The aim of this paper is to determine the health-related quality of life (HRQOL) of artisanal fisherwomen/shellfish gatherers from the Saubara municipality in Bahia, Brazil in comparison to the general population. A structured questionnaire was administered to a sample of 209 artisanal fisherwomen selected at random. The HRQOL questionnaire, known as the 36-Item Short-Form Health Survey version 1 (SF-36v01), was also used, having been translated and verified cross-culturally for the Brazilian population. Sociodemographic, lifestyle and comorbidity information was also collected. Chronic diseases and indicators of musculoskeletal disorders (MSDs) were self-reported. The study population consisted primarily of individuals between 30 and 45 years of age (78%), of self-classified races black or brown (96.2%), with no more than an elementary school education (77%) and married (64.6%). In all the SF-36v01 dimensions, the values in the sample were lower than in the general population of Brazil, which was used as the reference population. In the “Physical Health” domain (Physical Functioning; Physical Role Limitations; Bodily Pain; General Health Perception) a tendency toward a lower health-related quality of life was observed among those who were older, had a lower education level, and had a prevalence of MSDs, hypertension or arthritis. The interference of health conditions linked to the fisherwomen’s work activities may contribute to lower HRQOL in all analyzed aspects, in comparison to the general population. In light of these findings, public health policies must consider these informal workers who contribute greatly to Brazil’s economy and food system. PMID:27164118

  18. Seasonal dynamics of trophic relationships among co-occurring suspension-feeders in two shellfish culture dominated ecosystems

    NASA Astrophysics Data System (ADS)

    Lefebvre, Sébastien; Marín Leal, Julio César; Dubois, Stanislas; Orvain, Francis; Blin, Jean-Louis; Bataillé, Marie-Paule; Ourry, Alain; Galois, Robert

    2009-04-01

    The temporal dynamics of carbon and nitrogen isotope values of co-occurring suspension-feeders in two shellfish culture areas (Normandy, France) were investigated over two years to evaluate the inter-specific trophic partitioning and relative contributions of organic matter sources to benthic suspension-feeders' diet. Oysters ( Crassostrea gigas), mussels ( Mytilus edulis), cockles ( Cerastoderma edule), slipper limpets ( Crepidula fornicata), and sand-mason worms ( Lanice conchilega) were sampled in an estuarine environment (Baie des Veys, east Cotentin, Normandy), while oysters, mussels, slipper limpets, and honeycomb worms ( Sabellaria alveolata) were sampled in an open-marine environment (Lingreville-sur-mer, west Cotentin, Normandy). Whatever the sampling period, the bivalves, C. gigas and M. edulis, exhibited the lowest values of δ13C and δ15N compared with the other species. Feeding relationships among suspension-feeders in both C. gigas culture areas exhibited temporal variations due to the marine/estuarine influence and seasonal changes in food supply. In the open-marine ecosystem, the contribution of phytoplankton remained the most important for all species except S. alveolata, while in the estuarine ecosystem, microphytobenthos and/or macroalgae detritus contributed a larger extent to the organisms' diets. During phytoplankton bloom periods (e.g. May and July) suspension-feeders, except for S. alveolata, relied strongly on phytoplankton; however, the majority of suspension-feeders exhibited different opportunistic behaviour in winter when phytoplankton biomass might be a limiting factor. We hypothesized that differences in particle capture and selection by the suspension-feeders influenced their isotopic values. Feeding ecology of suspension-feeders partly explained why competition was limited and why ecosystems can often support unexpectedly large numbers of suspension-feeders. We also showed that understanding ecosystem characteristics of the organic

  19. Health-Related Quality of Life among Artisanal Fisherwomen/Shellfish Gatherers: Lower than the General Population.

    PubMed

    Müller, Juliana Dos Santos; Falcão, Ila Rocha; Couto, Maria Carolina Barreto Moreira; Viana, Wendel da Silva; Alves, Ivone Batista; Viola, Denise Nunes; Woods, Courtney Georgette; Rêgo, Rita Franco

    2016-01-01

    Quality of life is an indicator of how well one perceives that he/she is functioning physically and mentally. The aim of this paper is to determine the health-related quality of life (HRQOL) of artisanal fisherwomen/shellfish gatherers from the Saubara municipality in Bahia, Brazil in comparison to the general population. A structured questionnaire was administered to a sample of 209 artisanal fisherwomen selected at random. The HRQOL questionnaire, known as the 36-Item Short-Form Health Survey version 1 (SF-36v01), was also used, having been translated and verified cross-culturally for the Brazilian population. Sociodemographic, lifestyle and comorbidity information was also collected. Chronic diseases and indicators of musculoskeletal disorders (MSDs) were self-reported. The study population consisted primarily of individuals between 30 and 45 years of age (78%), of self-classified races black or brown (96.2%), with no more than an elementary school education (77%) and married (64.6%). In all the SF-36v01 dimensions, the values in the sample were lower than in the general population of Brazil, which was used as the reference population. In the "Physical Health" domain (Physical Functioning; Physical Role Limitations; Bodily Pain; General Health Perception) a tendency toward a lower health-related quality of life was observed among those who were older, had a lower education level, and had a prevalence of MSDs, hypertension or arthritis. The interference of health conditions linked to the fisherwomen's work activities may contribute to lower HRQOL in all analyzed aspects, in comparison to the general population. In light of these findings, public health policies must consider these informal workers who contribute greatly to Brazil's economy and food system. PMID:27164118

  20. Rapid Detection of Vibrio vulnificus in Shellfish and Gulf of Mexico Water by Real-Time PCR

    PubMed Central

    Panicker, Gitika; Myers, Michael L.; Bej, Asim K.

    2004-01-01

    In this paper we describe optimization of SYBR Green I-based real-time PCR parameters and testing of a large number of microbial species with vvh-specific oligonucleotide primers to establish a rapid, specific, and sensitive method for detection of Vibrio vulnificus in oyster tissue homogenate and Gulf of Mexico water (gulf water). Selected oligonucleotide primers for the vvh gene were tested for PCR amplification of a 205-bp DNA fragment with a melting temperature of approximately 87°C for 84 clinical and environmental strains of V. vulnificus. No amplification was observed with other vibrios or nonvibrio strains with these primers. The minimum level of detection by the real-time PCR method was 1 pg of purified genomic DNA or 102 V. vulnificus cells in 1 g of unenriched oyster tissue homogenate or 10 ml of gulf water. It was possible to improve the level of detection to one V. vulnificus cell in samples that were enriched for 5 h. The standard curves prepared from the real-time PCR cycle threshold values revealed that there was a strong correlation between the number of cells in unenriched samples and the number of cells in enriched samples. Detection of a single cell of V. vulnificus in 1 g of enriched oyster tissue homogenate is in compliance with the recent Interstate Shellfish Sanitation Conference guidelines. The entire detection method, including sample processing, enrichment, and real-time PCR amplification, was completed within 8 h, making it a rapid single-day assay. Rapid and sensitive detection of V. vulnificus would ensure a steady supply of postharvest treated oysters to consumers, which should help decrease the number of illnesses or outbreaks caused by this pathogen. PMID:14711681

  1. Acoustic habitat and shellfish mapping and monitoring in shallow coastal water - Sidescan sonar experiences in The Netherlands

    NASA Astrophysics Data System (ADS)

    van Overmeeren, Ronnie; Craeymeersch, Johan; van Dalfsen, Jan; Fey, Frouke; van Heteren, Sytze; Meesters, Erik

    2009-11-01

    Sidescan sonar has been applied in a number of shallow water environments along the Dutch coast to map and monitor shellfish and seabed habitats. The littoral setting of these surveys may hamper data acquisition flying the towfish in zones of turbulence and waves, but also offers valuable opportunities for understanding, interpreting and validating sidescan sonar images because of the ability to ground-truth during low water periods, enabling easy identification and validation. Acoustical images of some of the mussel banks on the tidal flats of the Wadden Sea, recorded at high tide, show a marked resemblance with optical Google Earth images of the same banks. These sonar images may thus serve as ' acoustic type signatures' for the interpretation of sonar patterns recorded in deeper water where ground-truthing is more difficult and more expensive. Similarly, acoustic type signatures of (Japanese) oyster banks were obtained in the estuaries in the southwest of the Netherlands. Automated acoustic pattern recognition of different habitats and acoustical estimation of faunal cover and density are possible applications of sidescan sonar. Both require that the backscattering observed on the sidescan sonar images is directly caused by the biological component of the seafloor. Filtering offers a simple and effective pre-processing technique to separate the faunal signals from linear trends such as emanating from wave ripples or the central tracks of the towfish. Acoustically estimating the faunal density is approached by in-situ counting peaks in backscattering in unit squares. These counts must be calibrated by ground-truthing. Ground-truthing on littoral mussel banks in the Wadden Sea has been carried out by measuring their cover along lines during low tide. Due to its capacity of yielding full-cover, high resolution images of large surfaces, sidescan sonar proves to be an excellent, cost-effective tool for quantitative time-lapse monitoring of habitats.

  2. The purine degradation pathway: possible role in paralytic shellfish toxin metabolism in the cyanobacterium Planktothrix sp. FP1.

    PubMed

    Pomati, F; Manarolla, G; Rossi, O; Vigetti, D; Rossetti, C

    2001-12-01

    The paralytic shellfish toxins (PSTs) are potent neurotoxic alkaloids and their major biological effect is due to the blockage of voltage-gated sodium channels in excitable cells. They have been recognised as an important health risk for humans, animals, and ecosystems worldwide. The metabolic pathways that lead to the production and the degradation of these toxic metabolites are still unknown. In this study, we investigated the possible link between PST accumulation and the activation of the metabolism that leads to purine degradation in the filamentous freshwater cyanobacterium Planktothrix sp. FP1. The purine catabolic pathway is related to the nitrogen microcycle in water environments, in which cyanobacteria use traces of purines and ureides as a nitrogen source for growth. Thus, the activity of allantoicase, a key inducible enzyme of this metabolism, was used as tool for assaying the activation of the purine degradation pathway. The enzyme and the pathway were induced by allantoic acid, the direct substrate of allantoicase, as well as by adenine and, to a lower degree, by urea, one of the main products of purine catabolism. Crude cell extract of Escherichia coli was also employed and showed the best induction of allantoicase activity. In culture, Planktothrix sp. FP1 showed a differential accumulation of PST in consequence of the induction with different substrates. The cyanobacterial culture induced with allantoic acid accumulated 61.7% more toxins in comparison with the control. On the other hand, the cultures induced with adenine, urea, and the E. coli extract showed low PST accumulation, respectively, 1%, 38%, and 5% of the total toxins content detected in the noninduced culture. A degradation pathway for the PSTs can be hypothesised: as suggested for purine alkaloids in higher plants, saxitoxin (STX) and derivatives may also be converted into xanthine, urea, and further to CO2 and NH4+ or recycled in the primary metabolism through the purine degradation

  3. Influence of Different Shellfish Matrices on the Separation of PSP Toxins Using a Postcolumn Oxidation Liquid Chromatography Method

    PubMed Central

    Rey, Verónica; Alfonso, Amparo; Botana, Luis M.; Botana, Ana M.

    2015-01-01

    The separation of PSP toxins using liquid chromatography with a post-column oxidation fluorescence detection method was performed with different matrices. The separation of PSP toxins depends on several factors, and it is crucial to take into account the presence of interfering matrix peaks to produce a good separation. The matrix peaks are not always the same, which is a significant issue when it comes to producing good, reliable results regarding resolution and toxicity information. Different real shellfish matrices (mussel, scallop, clam and oyster) were studied, and it was seen that the interference is not the same for each individual matrix. It also depends on the species, sampling location and the date of collection. It was proposed that separation should be accomplished taking into account the type of matrix, as well as the concentration of heptane sulfonate in both solvents, since the mobile phase varies regarding the matrix. Scallop and oyster matrices needed a decrease in the concentration of heptane sulfonate to separate GTX4 from matrix peaks, as well as dcGTX3 for oysters, with a concentration of 6.5 mM for solvent A and 6.25 mM for solvent B. For mussel and clam matrices, interfering peaks are not as large as they are in the other group, and the heptane sulfonate concentration was 8.25 mM for both solvents. Also, for scallops and oysters, matrix interferences depend not only on the sampling site but also on the date of collection as well as the species; for mussels and clams, differences are noted only when the sampling site varies. PMID:25884908

  4. Association between fish and shellfish, and omega-3 PUFAs intake and CVD risk factors in middle-aged female patients with type 2 diabetes

    PubMed Central

    Kim, Hyesook; Park, Seokyung; Yang, Hyesu; Choi, Young Ju; Huh, Kap Bum

    2015-01-01

    BACKGROUND/OBJECTIVES This study was performed to investigate the association between the dietary intake of fish and shellfish, and omega-3 polyunsaturated fatty acids (PUFAs) and cardiovascular disease (CVD) risk factors in the middle-aged Korean female patients with Type 2 diabetes (T2D). SUBJECTS/METHODS A cross-sectional analysis was performed with 356 female patients (means age: 55.5 years), who were recruited from the Huh's Diabetes Clinic in Seoul, Korea between 2005 and 2011. The dietary intake was assessed by a validated semi-quantitative food frequency questionnaire and analyzed using the Computer Aided Nutritional Analysis program (CAN-Pro) version 4.0 software. RESULTS In a multiple regression analysis after the adjustment for confounding factors such as age, BMI, duration of diagnosed T2D, alcohol consumption, fiber intake, sodium intake, and total energy intake, fish and shellfish intake of the subjects was negatively associated with triglyceride and pulse wave velocity (PWV). Omega-3 PUFAs intake was negatively associated with triglyceride, systolic blood pressures, diastolic blood pressures, and PWV. The multiple logistic regression analysis with the covariates showed a significant inverse relationship between the omega-3 PUFAs consumption and prevalence of hypertriglyceridemia [OR (95% CI) for greater than the median compared to less than the median: 0.395 (0.207-0.753)]. CONCLUSIONS These results suggest that the consumption of fish and shellfish, good sources of omega-3 PUFAs, may reduce the risk factors for CVD in the middle-aged female patients with T2D. PMID:26425279

  5. Evaluation of optimal conditions for determination of low selenium content in shellfish samples collected at Todos os Santos Bay, Bahia, Brazil using HG-AFS.

    PubMed

    Lopes Dos Santos, Walter Nei; Macedo, Samuel Marques; Teixeira da Rocha, Sofia Negreiros; Souza de Jesus, Caio Niela; Cavalcante, Dannuza Dias; Hatje, Vanessa

    2014-08-01

    This work proposes a procedure for the determination of total selenium content in shellfish after digestion of samples in block using cold finger system and detection using atomic fluorescent spectrometry coupled hydride generation (HG AFS). The optimal conditions for HG such as effect and volume of prereduction KBr 10 % (m/v) (1.0 and 2.0 ml) and concentration of hydrochloric acid (3.0 and 6.0 mol L(-1)) were evaluated. The best results were obtained using 3 mL of HCl (6 mol L(-1)) and 1 mL of KBr 10 % (m/v), followed by 30 min of prereduction for the volume of 1 mL of the digested sample. The precision and accuracy were assessed by the analysis of the Certified Reference Material NIST 1566b. Under the optimized conditions, the detection and quantification limits were 6.06 and 21.21 μg kg(-1), respectively. The developed method was applied to samples of shellfish (oysters, clams, and mussels) collected at Todos os Santos Bay, Bahia, Brazil. Selenium concentrations ranged from 0.23 ± 0.02 to 3.70 ± 0.27 mg kg(-1) for Mytella guyanensis and Anomalocardia brasiliana, respectively. The developed method proved to be accurate, precise, cheap, fast, and could be used for monitoring Se in shellfish samples. PMID:24771464

  6. Systematic detection of BMAA (β-N-methylamino-l-alanine) and DAB (2,4-diaminobutyric acid) in mollusks collected in shellfish production areas along the French coasts.

    PubMed

    Réveillon, Damien; Séchet, Véronique; Hess, Philipp; Amzil, Zouher

    2016-02-01

    The neurotoxin β-N-methylamino-l-alanine (BMAA) is naturally present in some microalgal species in the marine environment. The accumulation of BMAA has widely been observed in filter-feeding bivalves that are known to consume primary producers constituting the base of complex aquatic food webs. This study was performed to assess the occurrence of BMAA and isomers in mollusks collected from nine representative shellfish production areas located on the three French coasts (Channel, Atlantic and Mediterranean sites). The use of a highly selective and sensitive HILIC-MS/MS method, with D5DAB as internal standard, revealed the systematic detection of BMAA and DAB, in concentrations ranging from 0.20 to 6.7 μg g(-1) dry weight of digestive gland tissues of mollusks. While we detected BMAA in four strains of diatoms in a previous study, here BMAA was only detected in one diatom species previously not investigated out of the 23 microalgal species examined (belonging to seven classes). The concentrations of BMAA and DAB in mussels and oysters were similar at different sampling locations and despite the high diversity of phytoplankton populations that mollusks feed on at these locations. Only small variations of BMAA and DAB levels were observed and these were not correlated to any of the phytoplankton species reported. Therefore, extensive research should be performed on both origin and metabolism of BMAA in shellfish. The levels observed in this study are similar to those found in other studies in France or elsewhere. A previous study had related such levels to a cluster of Amyotrophic Lateral Sclerosis in the South of France; hence the widespread occurrence of BMAA in shellfish from all coasts in France found in this study suggests the need for further epidemiological and toxicological studies to establish the levels that are relevant for a link between the consumption of BMAA-containing foodstuffs and neurodegenerative diseases. PMID:26615827

  7. COMPARISON OF GENKENSIA DEMISSA (DILLWYN) POPULATIONS IN RHODE ISLAND FRINGE MARSHES WITH VARYING NITROGEN LOADS

    EPA Science Inventory

    Increased residential development in coastal watersheds has led to increases in anthropogenic nitrogen inputs into estuaries. Sessile bivalves are good candidate organisms to examine animal condition in nutrient-enriched areas because they contribute significantly to energy flow...

  8. Transient isotachophoresis-capillary zone electrophoresis with contactless conductivity and ultraviolet detection for the analysis of paralytic shellfish toxins in mussel samples.

    PubMed

    Abdul Keyon, Aemi S; Guijt, Rosanne M; Bolch, Christopher J S; Breadmore, Michael C

    2014-10-17

    The accumulation of paralytic shellfish toxins (PSTs) in contaminated shellfish is a serious health risk making early detection important to improve shellfish safety and biotoxin management. Capillary electrophoresis (CE) has been proven as a high resolution separation technique compatible with miniaturization, making it an attractive choice in the development of portable instrumentation for early, on-site detection of PSTs. In this work, capillary zone electrophoresis (CZE) with capacitively coupled contactless conductivity detector (C(4)D) and UV detection were examined with counter-flow transient isotachophoresis (tITP) to improve the sensitivity and deal with the high conductivity sample matrix. The high sodium concentration in the sample was used as the leading ion while l-alanine was used as the terminating electrolyte (TE) and background electrolyte (BGE) in which the toxins were separated. Careful optimization of the injected sample volume and duration of the counter-flow resulted in limit of detections (LODs) ranging from 74.2 to 1020 ng/mL for tITP-CZE-C(4)D and 141 to 461 ng/mL for tITP-CZE-UV, an 8-97 fold reduction compared to conventional CZE. The LODs were adequate for the analysis of PSTs in shellfish samples close to the regulatory limit. Intra-day and inter-day repeatability values (percentage relative standard deviation, n=3) of tITP-CZE-C(4)D and tITP-CZE-UV methods for both migration time and peak height were in the range of 0.82-11% and 0.76-10%, respectively. The developed method was applied to the analysis of a contaminated mussel sample and validated against an Association of Official Analytical Chemists (AOAC)-approved method for PSTs analysis by high performance liquid chromatography (HPLC) with fluorescence detection (FLD) after pre-column oxidation of the sample. The method presented has potential for incorporation in to field-deployable devices for the early detection of PSTs on-site. PMID:25223612

  9. Development and Validation of a Lateral Flow Immunoassay for the Rapid Screening of Okadaic Acid and All Dinophysis Toxins from Shellfish Extracts.

    PubMed

    Jawaid, Waqass; Meneely, Julie P; Campbell, Katrina; Melville, Karrie; Holmes, Stephen J; Rice, Jennifer; Elliott, Christopher T

    2015-09-30

    A single-step lateral flow immunoassay was developed and validated to detect okadaic acid (OA) and dinophysis toxins (DTXs), which cause diarrhetic shellfish poisoning. The performance characteristics of the test were investigated, in comparison to reference methods (liquid chromatography tandem mass spectrometry and/or bioassay), using both spiked and naturally contaminated shellfish. A portable reader was used to generate a qualitative result, indicating the absence or presence of OA-group toxins, at concentrations relevant to the maximum permitted level (MPL). Sample homogenates could be screened in 20 min (including extraction and assay time) for the presence of free toxins (OA, DTX1, DTX2). DTX3 detection could be included with the addition of a hydrolysis procedure. No matrix effects were observed from the species evaluated (mussels, scallops, oysters, and clams). Results from naturally contaminated samples (n = 72) indicated no false compliant results and no false noncompliant results at <50% MPL. Thus, the development of a new low-cost but highly effective tool for monitoring a range of important phycotoxins has been demonstrated. PMID:26287989

  10. Generation of a panel of high affinity antibodies and development of a biosensor-based immunoassay for the detection of okadaic acid in shellfish.

    PubMed

    Le Berre, Marie; Kilcoyne, Michelle; Kane, Marian

    2015-09-01

    Okadaic acid (OA) and its derivatives, DTX-1 and DTX-2, are marine biotoxins associated with diarrhetic shellfish poisoning. Routine monitoring of these toxins relies on the mouse bioassay. However, due to the technical unreliability and animal usage of this bioassay, there is always a need for convenient and reliable alternative assay methods. A panel of monoclonal antibodies against OA was generated and the most suitable was selected for biosensor-based assay development using surface plasmon resonance. The cross reactivity of the selected antibody with DTX-1 was found to be 73%, confirming the antibody suitability for both OA and DTX detection. The OA and derivative assay was designed as an inhibition assay covering the concentrations 1-75 ng/ml, with a sensitivity of 22.4 ng/ml. The assay was highly reproducible and preliminary validation showed no matrix interference from mussel extracts and good recovery of added standard in mussel extracts, with %CV of <9.3%. This assay could provide a useful and convenient screening tool for OA and its derivatives with a comprehensive extraction protocol for shellfish monitoring programmes. PMID:26169671

  11. A tyrosine-containing analog of mu-conotoxin GIIIA as ligand in the receptor binding assay for paralytic shellfish poisons.

    PubMed

    Mendoza, Aileen D L; Sombrito, Elvira Z; Cruz, Lourdes J

    2015-06-01

    Development of novel analytical tools to detect marine biotoxins has been warranted in view of the apparent global pervasiveness of algal-derived shellfish poisoning, and the limitations of existing methods. Here, we describe the initial phase in the development and evaluation of a tyrosine-containing analog of μ-conotoxin (μ-CTX) GIIIA as an alternative to saxitoxin (STX) in a receptor binding assay (RBA) for paralytic shellfish poisons. The peptide analog was synthesized and characterized for structure and bioactivity. The major product of oxidation elicited paralytic symptoms in mice at a minimum dose of 1.31 mg kg(-1) (i.p.). Mass spectrometry analysis of the bioactive peptide gave a molecular mass of 2637.52 Da that was close to the predicted value. Iodination via chloramine-T produced non-, mono- and di-iodinated peptides (respectively, NIP, MIP and DIP). Competition assays against (3)H-STX revealed higher Ki and EC50 (P < 0.0001, ANOVA) indicating reduced affinity for the receptor, and limited displacement of receptor-bound STX. However, subsequent use of MIP may extend the application of RBA to detect small changes in toxin levels owing to its likely enhanced displacement by STX. This may be useful in analyzing samples with toxicities near the regulatory limit, or in establishing baseline values in high risk environments. PMID:25817004

  12. Changes of paralytic shellfish toxins in gills and digestive glands of the cockle Cerastoderma edule under post-bloom natural conditions.

    PubMed

    Costa, Sara T; Vale, Carlos; Raimundo, Joana; Matias, Domitília; Botelho, Maria João

    2016-04-01

    Concentrations of the paralytic shellfish toxins C1+2, C3+4, GTX5, GTX6, dcGTX2+3, dcSTX, dcNEO, GTX2+3, GTX1+4, STX and NEO were determined by LC-FLD in composite samples of digestive glands and gills of Cerastoderma edule cockle. The specimens were sampled in Aveiro lagoon, Portugal, under natural depuration conditions (days 0, 8, 12, 14, 19, 21 and 25) after exposure to a bloom of Gymnodinium catenatum. Individual paralytic shellfish toxins indicated different pathways of elimination and biotransformation in digestive gland and gills. Toxin concentrations in gills were lower than in digestive gland. Most of the quantified toxins in digestive gland decreased during the 25 days of observation according to negative exponential curves, and only GTX5, GTX6 and NEO showed slight irregularities with time. Concentrations of C1+2, C3+4 and dcGTX2+3 in gills decreased progressively, however GTX5, GTX6 and dcSTX showed pronounced increases. Higher concentrations of those toxins in days 8 and 12 in comparison to the initial value (day 0) indicate conversion of other toxins into GTX5, GTX6 and dcSTX during those periods. It appears that inter-conversion of toxins occurs as G. catenatum cells are retained in gills before being transferred to other compartments. PMID:26874623

  13. Detection of cyanobacterial neurotoxin β-N-methylamino-l-alanine within shellfish in the diet of an ALS patient in Florida.

    PubMed

    Banack, Sandra Anne; Metcalf, James S; Bradley, Walter G; Cox, Paul Alan

    2014-11-01

    Cyanobacteria produce the neurotoxic amino acid β-N-methylamino-l-alanine (BMAA), which in contaminated marine waters has been found to accumulate in shellfish. Exposure to BMAA has been associated with an increased risk of neurodegenerative disease. Analysis of blinded samples found BMAA to be present in neuroproteins of individuals who died from ALS and ALS/PDC, but generally not in the brains of patients who died of causes unrelated to neurodegeneration or Huntington's disease, an autosomal dominant neurodegenerative disease. We here report support for a link between a patient with ALS and chronic exposure to the cyanobacterial neurotoxin BMAA via shellfish consumption. The patient had frequently eaten lobsters collected in Florida Bay for approximately 30 years. LC-MS/MS analysis of two lobsters which this ALS patient had placed in his freezer revealed BMAA at concentrations of 27 and 4 μg/g, respectively, as well as the presence of 2,4-diaminobutyric acid (DAB), a BMAA isomer. Two additional lobsters recently collected from Florida Bay also contained the neurotoxins BMAA and DAB. These data suggest that invertebrates collected in water where cyanobacterial blooms are present, if consumed, may result in direct human exposure to these neurotoxic amino acids. The data support the assertion that prolonged exposure to BMAA may have played a role in the etiology of ALS in this patient. PMID:25123936

  14. Suitability of tandem-in-time mass spectrometry for polybrominated diphenylether measurement in fish and shellfish samples: comparison with high resolution mass spectrometry.

    PubMed

    Pirard, Catherine; De Pauw, Edwin; Focant, Jean-François

    2006-05-19

    The first part of the present study focused on the development of an alternative automated sample preparation method for the measurement of selected polybrominated diphenyl ethers (PBDEs) in fish and shellfish. A previously developed automated method has been further optimized and simplified to decrease blank levels and cost. Sorbent and solvent quantities have been significantly reduced without altering extract quality. The second part of the study consisted of comparing tandem-in-time quadrupole ion storage mass spectrometry (QISTMS/MS) to high resolution mass spectrometry (HRMS) for the isotope dilution (ID) measurement step after gas chromatography (GC) separation. Both mass spectrometric methods performed similarly in terms of accuracy but better precision was observed for HRMS. Although better sensitivity can be attained with the high resolution sector instrument, method limits of quantification (mLOQs) were very similar for both approaches as they were dependent on the procedural blanks levels. The mLOQ values ranged between 0.04 and 3.56 ng/g fat, depending on the congener. They allowed the unambiguous identification and quantification of all target analytes, except for BDE-183, in most considered fish extracts. An analytical procedure based on rapid automated sample preparation and QISTMS/MS appeared to be suitable for the measurement of PBDEs in fish and shellfish speciment under quality assurance/quality control (QA/QC) criteria. PMID:16564052

  15. Report on the development of the FAO/INFOODS user database for fish and shellfish (uFiSh) - Challenges and possible solutions.

    PubMed

    Rittenschober, Doris; Stadlmayr, Barbara; Nowak, Verena; Du, Juan; Charrondiere, U Ruth

    2016-02-15

    Reliable food composition data are required for virtually all nutrition-related programs and policies. In many food composition tables, fish are included to a limited extent. Therefore, FAO/INFOODS decided to compile and publish a user databases for fish and shellfish (uFiSh), considering the following main objectives: to develop a global database for fish, crustaceans and molluscs with raw, cooked and processed foods; to base the database preferable on analytical data; to include major as well as minor species consumed; and to capture intra-species variation due to habitat, edible part, season or region. The development of the uFiSh is based on FAO/INFOODS international standards and guidelines. The paper describes challenges and possible solution of data compilation specific to fish and shellfish, as well as the uFiSh in terms of its structure, including coverage of nutrients, documentation and format of publication. The first edition is intended to be published in 2015. PMID:26433296

  16. Single-laboratory validation study of rapid analysis method for multi-class veterinary drugs in milk, fish and shellfish by LC-MS/MS.

    PubMed

    Nakajima, Takayuki; Nagano, Chieko; Kanda, Maki; Hayashi, Hiroshi; Hashimoto, Tsuneo; Kanai, Setsuko; Matsushima, Yoko; Tateishi, Yukinari; Sasamoto, Takeo; Takano, Ichiro

    2013-01-01

    A method of rapid analysis of multi-class residual veterinary drugs in milk, fish and shellfish was validated in accordance with Japanese guidelines for the validation of analytical methods for residual agricultural chemicals in food. Using LC-MS/MS, 43 multi-class veterinary drugs, including sulfonamides, quinolones, coccidiostats and antiparasites, could be analyzed in one injection. Analytes were extracted from samples with two kinds of solvent, acetonitrile containing 1 vol% formic acid and anhydrous acetonitrile, and salted out with 4.0 g of magnesium sulfate, 1.5 g of trisodium citrate and 2.0 g of sodium chloride. This method was assessed by performing recovery tests in retail milk and 4 kinds of fresh cultured fish and shellfish (salmon, tiger shrimp, red sea bream and bastard halibut) spiked with the 43 target analytes at the levels of 10 and 100 μg/kg. Using this method, 40 out of 43 drugs satisfied the guideline criteria in milk, 37 drugs in salmon, 42 drugs in tiger shrimp, 41 drugs in red sea bream and 39 drugs in bastard halibut. PMID:24025214

  17. Radioactive contamination of fish, shellfish, and waterfowl exposed to Hanford effluents: Annual summaries, 1945--1972. Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Hanf, R.W.; Dirkes, R.L.; Duncan, J.P.

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction Project (HEDR) is to estimate the potential radiation doses received by people living within the sphere of influence of the Hanford Site. A potential critical pathway for human radiation exposure is through the consumption of waterfowl that frequent onsite waste-water ponds or through eating of fish, shellfish, and waterfowl that reside in/on the Columbia River and its tributaries downstream of the reactors. This document summarizes information on fish, shellfish, and waterfowl radiation contamination for samples collected by Hanford monitoring personnel and offsite agencies for the period 1945 to 1972. Specific information includes the types of organisms sampled, the kinds of tissues and organs analyzed, the sampling locations, and the radionuclides reported. Some tissue concentrations are also included. We anticipate that these yearly summaries will be helpful to individuals and organizations interested in evaluating aquatic pathway information for locations impacted by Hanford operations and will be useful for planning the direction of future HEDR studies.

  18. Buying, Preparing, and Cooking Shellfish. Learning Activity Pack and Instructor's Guide 5.13c. Commercial Foods and Culinary Arts Competency-Based Series. Section 5: Basic Food Preparation.

    ERIC Educational Resources Information Center

    Florida State Univ., Tallahassee. Center for Studies in Vocational Education.

    This document consists of a learning activity packet (LAP) for the student and an instructor's guide for the teacher. The LAP is intended to acquaint occupational home economics students with the various market forms of shellfish and how to clean, prepare, and cook them. Illustrated information sheets and learning activities are provided in these…

  19. Evaluation of tidal marsh restoration: Comparison of selected macroinvertebrate populations on a restored impounded valley marsh and an unimpounded valley marsh within the same salt marsh system in Connecticut, USA

    NASA Astrophysics Data System (ADS)

    Peck, Myron A.; Fell, Paul E.; Allen, Elizabeth A.; Gieg, Jennifer A.; Guthke, Carl R.; Newkirk, Michael D.

    1994-03-01

    Macroinvertebrates were examined on an impounded valley marsh in Stonington, Connecticut, that has changed from a Typha-dominated system to one with typical salt-marsh vegetation during 13 years following the reintroduction of tidal exchange. Animal populations on this restored impounded marsh were evaluated by comparing them with populations on a nearby unimpounded valley marsh of roughly the same size. Populations of the high marsh snail, Melampus bidentatus Say, were quantitatively sampled along transects that extended from the water-marsh edge to the upland; those of the ribbed mussel, Geukensia demissa Dillwyn, were sampled in low marsh areas on transects along the banks of creeks and mosquito ditches. The occurrence of other marsh invertebrates also was documented, but their abundance was not measured. The mean density of Melampus was 332±39.6 SE/m2 on the restored impounded marsh and 712±56.0 SE/m2 on the unimpounded marsh. However, since snails were larger on the restored impounded marsh, the difference in snail biomass was less pronounced than the difference in snail density. Mean Melampus biomass was 4.96±0.52 SE g dry wt/m2 on the restored impounded marsh and 6.96±0.52 SE g dry wt/m2 on the unimpounded marsh. On the two marshes, snail density and biomass varied in relation to plant cover and other factors. The density and biomass of Geukensia at the edge of the marsh were comparable on the restored impounded and unimpounded marshes. Mean mussel densities ranged from 80 to 240/m2 and mean mussel biomass varied from 24.8-64.8 g dry wt/m2 in different low marsh areas. In contrast, below the impoundment dike, mean Geukensia density was 1100±96.4 SE/m2 and mean Geukensia biomass was 303.6±33.28 SE g dry wt/m2. A consideration of all available evidence leads to the conclusion that the impounded marsh is in an advanced phase of restoration.

  20. Poisoning - fish and shellfish

    MedlinePlus

    ... contaminated waters. Scombroid poisoning usually occurs from large, dark meat fish such as tuna, mackerel, mahi mahi, and albacore. Because this poison develops after a fish is caught and dies, it does not matter where the fish is caught. The main factor ...

  1. Amnesic Shellfish Poisoning

    MedlinePlus

    ... year, domoic acid was also measured in razor clams collected on Washington State beaches. Since then, the ... multiseries California Mussel Rock crab Dungeness crab Razor clams Sand crab ( Emerita ) P. australis P. cuspidata Washington ...

  2. Inorganic carbon dynamics in the upwelling system off the Oregon coast and implications for commercial shellfish hatcheries

    NASA Astrophysics Data System (ADS)

    Vance, J. M.; Hales, B. R.

    2010-12-01

    The increasing absorption of anthropogenic CO2 by the global ocean and concomitant decrease in pH will alter seawater carbonate chemistry in ways that may negatively impact calcifying organisms. In particular, the change in saturation state (Ω) of calcium carbonate minerals calcite and aragonite may be energetically unfavorable for shell formation while favoring shell dissolution. Eastern boundary upwelling systems may provide insights into how ecosystems respond to future conditions of ocean acidification when deep water with high dissolved inorganic carbon (DIC), low pH and low Ω is forced toward the surface. Mortality in commercial seed stock and reduced wild set of the oyster Crassostrea gigas in the northeast Pacific during 2005-2009 reinforced the need for understanding biological responses to acidified ocean water. In response, a long-term strategy to understand local carbonate chemistry dynamics, seasonal perturbations and the effects on development of calcifying bivalves was developed. At present, a time-series of pCO2 measurements was implemented in April 2010 in Netarts Bay, Oregon at Whiskey Creek Shellfish Hatchery (WCH). The intake sits at a depth of 0.5-8ft and water is pumped in at 100gpm. A line taken off the intake is run continuously through a thermosalinograph at approximately 1.5gpm into a showerhead style equilibrator in which the headspace is recirculated by aerating the water for enhanced gas exchange. CO2 in equilibrated air is analyzed by NDIR. Additionally two discrete samples of intake seawater were taken across tidal cycles weekly and analyzed for total CO2 (TCO2) according to the methods of Hales et al. (2004) and pCO2 for quality control. The pCO2 in the bay exhibits a diurnal cycle representative of daytime photosynthesis and nighttime respiration. However, the phasing and profiles of these cycles are dominated by tidal mixing and are affected by the introduction of high pCO2 water during upwelling events. Diurnal pCO2 during

  3. Are fecal stanols suitable to record and identify a pulse of human fecal contamination in short-term exposed shellfish? A microcosm study.

    PubMed

    Harrault, Loïc; Jardé, Emilie; Jeanneau, Laurent; Petitjean, Patrice

    2014-12-15

    In this study, the capacity of oysters to bioaccumulate fecal stanols and to record a source-specific fingerprint was investigated by the short-term contamination of seawater microcosms containing oysters with a human effluent. Contaminated oysters bioaccumulated the typical fecal stanols coprostanol and 24-ethylcoprostanol and their bioaccumulation kinetics were similar to that of the Fecal Indicator Bacteria Escherichia coli used in European legislation. Although stanol fingerprints of contaminated water allowed the identification of the human specific fingerprint, this was not the case for oysters. This discrepancy is attributed to (i) high concentrations of endogenous cholestanol and sitostanol, responsible for "unbalanced" stanol fingerprints, (ii) different accumulation/depuration kinetics of fecal coprostanol and 24-ethylcoprostanol and (iii) the limits of the analytical pathway used. These results show that fecal stanols bioaccumulated by oysters are useful to record fecal contamination but the usefulness of stanol fingerprints to identify specific sources of contamination in shellfish currently seems limited. PMID:25455370

  4. [Can solar/geomagnetic activity restrict the occurrence of some shellfish poisoning outbreaks? The example of PSP caused by Gymnodinium catenatum at the Atlantic Portuguese coast].

    PubMed

    Vale, P

    2013-01-01

    Cyclic outbreaks of accumulation of paralytic shellfish poisoning (PSP) toxins in mussels attributed to Gymnodinium catenatum blooms displayed several of the highest inter-annual maxima coincidental with minima of the 11-year solar sunspot number (SSN) cycle. The monthly distribution of PSP was associated with low levels of the solar radio flux, a more quantitative approach than SSN for fluctuations in solar activity. A comparison between monthly distribution of PSP and other common biotoxins (okadaic acid (OA), dinophysistoxin-2 (DTX2) and amnesic shellfish poisoning (ASP) toxins) demonstrated that only PSP was significantly associated with low levels of radio flux (p < 0.01). PSP occurrence suggests a prior decline in solar activity could be required to act as a trigger, in a similar manner to a photoperiodic signal. The seasonal frequency increased towards autumn during the study period, which might be related to the progressive atmospheric cut-off of deleterious radiation associated with the seasonal change in solar declination, and might play an additional role in seasonal signal-triggering. PSP distribution was also associated with low levels of the geomagnetic index Aa. A comparison between monthly distribution of PSP and other common biotoxins, also demonstrated that only PSP was significantly associated with low levels of the Aa index (p < 0.01). In some years of SSN minima no significant PSP-outbreaks in mussels were detected. This was attributed to a steady rise in geomagnetic activity that could disrupt the triggering signal. Global distribution patterns show that hotspots for G. catenatum blooms are regions with deficient crustal magnetic anomalies. In addition to the variable magnetic field mostly of solar origin, static fields related to magnetized rocks in the crust and upper mantle might play a role in restricting worldwide geographic distribution. PMID:24455892

  5. Application of the neuroblastoma assay for paralytic shellfish poisons to neurotoxic freshwater cyanobacteria: interlaboratory calibration and comparison with other methods of analysis.

    PubMed

    Humpage, Andrew R; Ledreux, Aurélie; Fanok, Stella; Bernard, Cécile; Briand, Jean-François; Eaglesham, Geoff; Papageorgiou, John; Nicholson, Brenton; Steffensen, Dennis

    2007-07-01

    Paralytic shellfish poisons (PSPs) are produced by freshwater cyanobacteria and pose a threat to human and animal drinking-water supplies. The wide range of toxin analogues (and the likelihood that further analogues remain to be discovered) means that chromatographic methods are not always reliable indicators of toxicity. Although the mouse bioassay remains the method of choice in the seafood industry, its use is increasingly being questioned on ethical grounds. The cell-based Neuro-2A neuroblastoma toxicity assay is an alternative bioassay validated for testing shellfish extracts, so it was of interest to determine its applicability with the different suite of toxin analogues produced by cyanobacteria. Cyanobacterial bloom samples from Australia, Brazil, and France were assayed using the neuroblastoma assay, liquid chromatography-tandem mass spectrometry (LC-MS/MS), high-performance liquid chromatography with postcolumn derivatization and fluorescence detection, and the Jellett Rapid Test for PSP. To assess interlaboratory variability, the neuroblastoma assay was set up in laboratories in Paris (France) and Adelaide (Australia). Neuroblastoma and chromatographic methods gave comparable results except in the case of the neurotoxic Brazilian samples: LC-MS/MS did not detect the putative new PSPs contained in these samples. Inter- and intralaboratory variability of the neuroblastoma assay was typical of biological assays but no greater than that found for interassay variability between different chromatographic determinations. The batch of Jellett Rapid Tests for PSP used did not yield quantitative results. Overall, the neuroblastoma assay was useful as a screening assay for determination of toxicity caused by saxitoxin neurotoxins in freshwater cyanobacteria, having the advantage of being sensitive to unidentified toxins that currently cannot be quantified by chromatographic means. PMID:17665694

  6. Performance Characteristics of AOAC Method 2005.06 for the Determination of Paralytic Shellfish Toxins in Manila Clams, European Otter Clams, Grooved Carpet Shell Clams, Surf Clams, and Processed King Scallops.

    PubMed

    O'Neill, Alison; Turner, Andrew D

    2015-01-01

    An approach was developed for the verification of method performance of the AOAC 2005.06 LC-fluorescence detector (FLD) method for determination of paralytic shellfish poisoning (PSP) toxins in bivalve shellfish. This was developed following advice published by the Analytical Laboratory Accreditation Criteria Committee and applied to shellfish species that had not been previously subjected to a full single-laboratory validation scheme. The refined approach was developed following the need to assess performance in a number of shellfish species infrequently monitored through the UK statutory monitoring program, while reducing the impact and cost of the studies, most notably in terms of the use of valuable reference standards. The species assessed were manila clams (Ruditapes philippinarum), European otter clams (Lutraria lutraria), grooved carpet shell clams (R. decussatus), surf clams (Spisula solida), and king scallops (Pecten maximus) presented as adductor only or adductor plus roe. The method was assessed for sensitivity in terms of LOD and LOQ, toxin recovery, and method precision in each species. It incorporated the PSP toxins deemed toxic and/or prevalent in UK samples and commercially available as certified reference standards. The toxins studied included GTX1-5, dcSTX, STX, C1&2, and NEO. The toxins dcGTX2&3 were included for surf clams due to the prevalence of these toxins in this species as a result of toxin decarbamoylation. Method performance targets were met for each of the characteristics investigated. Consequently, the method was deemed fit for purpose for the screening and quantification of these clam and scallop species for PSP toxins by AOAC Method 2005.06 LC-FLD. PMID:26024751

  7. Winter-summer nutrient composition linkage to algae-produced toxins in shellfish at a eutrophic coastal lagoon (Óbidos lagoon, Portugal)

    NASA Astrophysics Data System (ADS)

    Pereira, Patrícia; Botelho, Maria João; Cabrita, Maria Teresa; Vale, Carlos; Moita, Maria Teresa; Gonçalves, Célia

    2012-10-01

    The current work examines the linkage of pronounced winter-summer fluctuations on the nutrient composition with phytoplankton assemblages and mussel toxicity produced by the presence of toxic dinoflagellates. The work was performed at the Óbidos lagoon, a coastal eutrophic ecosystem that is permanently connected to an area characterized by frequent upwelling episodes. The lagoon and adjoining coastal area exhibit recurrent incidents of diarrhetic and paralytic shellfish poisoning. The conclusions are based on: (1) inorganic and organic nutrients at five sites of the lower, middle and upper Óbidos lagoon, and inorganic nutrients at two sites of the adjacent coastal area; biannual campaigns were performed in winter and summer between 2006 and 2010; (2) phytoplankton assemblages at three sites of the lagoon (located at lower and upper areas) in winter and summer of 2009; (3) algae-derived toxicity of wild mussels from the lower lagoon and coastal area, on a 1-2 week time scale, over 2006 and 2009. Nutrient molar ratios in Óbidos lagoon contrast between winter and summer. The lower median ratios DIN:P (31 and 0.8) and Si:P (11 and 3.3) in summer reflect the excess of phosphate. Excess was mainly attributed to phosphorus regeneration in sediments of the upper lagoon with accentuated symptoms of eutrophication. Dissolved organic nitrogen and dissolved organic phosphorus were also higher in summer, particularly in this area. No significant winter-summer differences were recorded for nutrient ratios in the adjacent coastal area. Phytoplankton assemblages pointed to a winter-summer contrast characterized by a shift of non-siliceous-based phytoplankton to diatoms. The toxic dinoflagellate species (Gymnodinium catenatum, Dinophysis cf. acuminata and Dinophysis acuta), presumably imported from the adjacent coast following upwelling episodes in summer, were observed in the lower lagoon. In summer of the two surveyed years, toxins produced by dinoflagellates occurred in

  8. Liquid Chromatography with a Fluorimetric Detection Method for Analysis of Paralytic Shellfish Toxins and Tetrodotoxin Based on a Porous Graphitic Carbon Column

    PubMed Central

    Rey, Veronica; Botana, Ana M.; Alvarez, Mercedes; Antelo, Alvaro; Botana, Luis M.

    2016-01-01

    Paralytic shellfish toxins (PST) traditionally have been analyzed by liquid chromatography with either pre- or post-column derivatization and always with a silica-based stationary phase. This technique resulted in different methods that need more than one run to analyze the toxins. Furthermore, tetrodotoxin (TTX) was recently found in bivalves of northward locations in Europe due to climate change, so it is important to analyze it along with PST because their signs of toxicity are similar in the bioassay. The methods described here detail a new approach to eliminate different runs, by using a new porous graphitic carbon stationary phase. Firstly we describe the separation of 13 PST that belong to different groups, taking into account the side-chains of substituents, in one single run of less than 30 min with good reproducibility. The method was assayed in four shellfish matrices: mussel (Mytillus galloprovincialis), clam (Pecten maximus), scallop (Ruditapes decussatus) and oyster (Ostrea edulis). The results for all of the parameters studied are provided, and the detection limits for the majority of toxins were improved with regard to previous liquid chromatography methods: the lowest values were those for decarbamoyl-gonyautoxin 2 (dcGTX2) and gonyautoxin 2 (GTX2) in mussel (0.0001 mg saxitoxin (STX)·diHCl kg−1 for each toxin), decarbamoyl-saxitoxin (dcSTX) in clam (0.0003 mg STX·diHCl kg−1), N-sulfocarbamoyl-gonyautoxins 2 and 3 (C1 and C2) in scallop (0.0001 mg STX·diHCl kg−1 for each toxin) and dcSTX (0.0003 mg STX·diHCl kg−1 ) in oyster; gonyautoxin 2 (GTX2) showed the highest limit of detection in oyster (0.0366 mg STX·diHCl kg−1). Secondly, we propose a modification of the method for the simultaneous analysis of PST and TTX, with some minor changes in the solvent gradient, although the detection limit for TTX does not allow its use nowadays for regulatory purposes. PMID:27367728

  9. In-house validation of a liquid chromatography tandem mass spectrometry method for the analysis of lipophilic marine toxins in shellfish using matrix-matched calibration.

    PubMed

    Gerssen, Arjen; van Olst, Erik H W; Mulder, Patrick P J; de Boer, Jacob

    2010-08-01

    A liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the quantitative analysis of lipophilic marine toxins in shellfish extracts (mussel, oyster, cockle and clam) was validated in-house using European Union (EU) Commission Decision 2002/657/EC as a guideline. The validation included the toxins okadaic acid (OA), yessotoxin (YTX), azaspiracid-1 (AZA1), pectenotoxin-2 (PTX2) and 13-desmethyl spirolide-C (SPX1). Validation was performed at 0.5, 1 and 1.5 times the current EU permitted levels, which are 160 microg kg(-1) for OA, AZA1 and PTX2 and 1,000 microg kg(-1) for YTX. For SPX1, 400 microg kg(-1) was chosen as the target level as no legislation has been established yet for this compound. The method was validated for determination in crude methanolic shellfish extracts and for extracts purified by solid-phase extraction (SPE). Extracts were also subjected to hydrolysis conditions to determine the performance of the method for OA and dinophysistoxin esters. The toxins were quantified against a set of matrix-matched standards instead of standard solutions in methanol. To save valuable standard, methanolic extract instead of the homogenate was spiked with the toxin standard. This was justified by the fact that the extraction efficiency is high for all relevant toxins (above 90%). The method performed very well with respect to accuracy, intraday precision (repeatability), interday precision (within-laboratory reproducibility), linearity, decision limit, specificity and ruggedness. At the permitted level the accuracy ranged from 102 to 111%, the repeatability from 2.6 to 6.7% and the reproducibility from 4.7 to 14.2% in crude methanolic extracts. The crude extracts performed less satisfactorily with respect to the linearity (less than 0.990) and the change in LC-MS/MS sensitivity during the series (more than 25%). SPE purification resulted in greatly improved linearity and signal stability during the series. Recently the European Food Safety Authority

  10. Liquid Chromatography with a Fluorimetric Detection Method for Analysis of Paralytic Shellfish Toxins and Tetrodotoxin Based on a Porous Graphitic Carbon Column.

    PubMed

    Rey, Veronica; Botana, Ana M; Alvarez, Mercedes; Antelo, Alvaro; Botana, Luis M

    2016-01-01

    Paralytic shellfish toxins (PST) traditionally have been analyzed by liquid chromatography with either pre- or post-column derivatization and always with a silica-based stationary phase. This technique resulted in different methods that need more than one run to analyze the toxins. Furthermore, tetrodotoxin (TTX) was recently found in bivalves of northward locations in Europe due to climate change, so it is important to analyze it along with PST because their signs of toxicity are similar in the bioassay. The methods described here detail a new approach to eliminate different runs, by using a new porous graphitic carbon stationary phase. Firstly we describe the separation of 13 PST that belong to different groups, taking into account the side-chains of substituents, in one single run of less than 30 min with good reproducibility. The method was assayed in four shellfish matrices: mussel (Mytillus galloprovincialis), clam (Pecten maximus), scallop (Ruditapes decussatus) and oyster (Ostrea edulis). The results for all of the parameters studied are provided, and the detection limits for the majority of toxins were improved with regard to previous liquid chromatography methods: the lowest values were those for decarbamoyl-gonyautoxin 2 (dcGTX2) and gonyautoxin 2 (GTX2) in mussel (0.0001 mg saxitoxin (STX)·diHCl kg(-1) for each toxin), decarbamoyl-saxitoxin (dcSTX) in clam (0.0003 mg STX·diHCl kg(-1)), N-sulfocarbamoyl-gonyautoxins 2 and 3 (C1 and C2) in scallop (0.0001 mg STX·diHCl kg(-1) for each toxin) and dcSTX (0.0003 mg STX·diHCl kg(-1) ) in oyster; gonyautoxin 2 (GTX2) showed the highest limit of detection in oyster (0.0366 mg STX·diHCl kg(-1)). Secondly, we propose a modification of the method for the simultaneous analysis of PST and TTX, with some minor changes in the solvent gradient, although the detection limit for TTX does not allow its use nowadays for regulatory purposes. PMID:27367728

  11. Histopathological survey of potential biomarkers for the assessment of contaminant related biological effects in species of fish and shellfish collected from Kuwait Bay, Arabian Gulf.

    PubMed

    Stentiford, G D; Massoud, M S; Al-Mudhhi, S; Al-Sarawi, M A; Al-Enezi, M; Lyons, B P

    2014-07-01

    The marine environment in Kuwait is dominated by Kuwait Bay, a shallow, depositional habitat vital for the breeding and propagation of marine organisms. The bay receives effluent inputs from industrial centres, ports, sewage outflows along with discharges from power and desalination plants. The major classes of pollutant discharged into the bay include petroleum hydrocarbons, metals, nutrients, cooling water and hyper-saline water. Further, the bay has been historically impacted by a deliberate release of oil and contamination with ordnance and shipwrecks during the 1991 Gulf war. With an aim to establish an integrated pollution effects monitoring programme in Kuwait, this paper describes the application of a quality assured approach to conduct a histopathology baseline survey in oriental sole (Synaptura orientalis) and the large-toothed flounder (Pseudorhombus arsius), which are two potential sentinel flatfish species present in the Arabian Gulf. Liver and gonadal histopathology revealed a range of pathologies similar to those previously observed in European and American pollution effects surveys that utilise flatfish (including pathology markers indicative of possible carcinogenesis and endocrine disruption). Further, we extended these studies to invertebrates (Jinga prawn, Metapenaeus affinis and the grooved tiger prawn, Penaeus semisulcatus) found within the Arabian Gulf. Such baseline data is essential before attempts are made to develop integrated monitoring programmes that aim to assess the health of fish and shellfish in relation to chemical contamination. PMID:24680107

  12. Confirmation of Pinnatoxins and Spirolides in Shellfish and Passive Samplers from Catalonia (Spain) by Liquid Chromatography Coupled with Triple Quadrupole and High-Resolution Hybrid Tandem Mass Spectrometry

    PubMed Central

    García-Altares, María; Casanova, Alexis; Bane, Vaishali; Diogène, Jorge; Furey, Ambrose; de la Iglesia, Pablo

    2014-01-01

    Cyclic imines are lipophilic marine toxins that bioaccumulate in seafood. Their structure comprises a cyclic-imino moiety, responsible for acute neurotoxicity in mice. Cyclic imines have not been linked yet to human poisonings and are not regulated in Europe, although the European Food Safety Authority requires more data to perform a conclusive risk assessment for consumers. This work presents the first detection of pinnatoxin G (PnTX-G) in Spain and 13-desmethyl spirolide C (SPX-1) in shellfish from Catalonia (Spain, NW Mediterranean Sea). Cyclic imines were found at low concentrations (2 to 60 µg/kg) in 13 samples of mussels and oysters (22 samples analyzed). Pinnatoxin G has been also detected in 17 seawater samples (out of 34) using solid phase adsorption toxin tracking devices (0.3 to 0.9 µg/kg-resin). Pinnatoxin G and SPX-1 were confirmed with both low and high resolution (<2 ppm) mass spectrometry by comparison of the response with that from reference standards. For other analogs without reference standards, we applied a strategy combining low resolution MS with a triple quadrupole mass analyzer for a fast and reliable screening, and high resolution MS LTQ Orbitrap® for unambiguous confirmation. The advantages and limitations of using high resolution MS without reference standards were discussed. PMID:24960460

  13. A feedback mechanism to control apoptosis occurs in the digestive gland of the oyster crassostrea gigas exposed to the paralytic shellfish toxins producer Alexandrium catenella.

    PubMed

    Rolland, Jean-Luc; Medhioub, Walid; Vergnes, Agnes; Abi-Khalil, Celina; Savar, Véronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed

    2014-09-01

    To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in caspase-3/7 activity and normal percentage of apoptotic cells in this tissue. Taken together, these results suggest a feedback mechanism, which may occur in the digestive gland where BI.1 could play a key role in preventing the induction of apoptosis by PSTs. Moreover, the expression of CYP1A, Bax and BI.1 were found to be significantly correlated to the occurrence of natural toxic events, suggesting that the expression of these genes together could be used as biomarker to assess the biological responses of oysters to stress caused by PSTs. PMID:25257788

  14. Long-term impacts of human harvesting on shellfish: North Iberian top shells and limpets from the Upper Palaeolithic to the present

    NASA Astrophysics Data System (ADS)

    Turrero, Pablo; Muñoz-Colmenero, A. Marta; Prado, Andrea; Garcia-Vazquez, Eva

    2014-11-01

    Humans have contributed to phenotypic and demographic changes in their prey from very early on in the colonization of Europe, including the harvesting of shellfish in coastal ecosystems. We estimated trends in population growth (variation in the number of individuals) from DNA sequences of modern specimens in two North Iberian molluscs, top shells (Osilinus lineatus, from 24 sequences and 14 haplotypes) and limpets (Patella vulgata, taken from the bibliography), which were subjected to very different levels of harvesting pressure during the Upper Palaeolithic (~ 20000 to ~ 6000 years ago). The less harvested Osilinus top shells experienced fluctuations in population numbers coincident with climatic oscillations. Patella limpets, which were harvested in greater numbers, suffered clear and uninterrupted decreases in their numbers during the Upper Palaeolithic. These trends coincided with morphological changes in shell size (length or width) in the same direction (i.e., shell size decreased when population size decreased and vice versa). The differing trends seen in taxa subjected to different intensities of harvesting pressure suggest that climate effects were overcome by anthropogenic selection (leading to a smaller average length) in limpets. We suggest that intense fishing pressure may have induced irreversible shell length decreases in the most exploited species.

  15. Development of the analysis of fecal stanols in the oyster Crassostrea gigas and identification of fecal contamination in shellfish harvesting areas.

    PubMed

    Harrault, Loïc; Jardé, Emilie; Jeanneau, Laurent; Petitjean, Patrice

    2014-06-01

    The objective of this work was to study the effects of washing and purification steps on qualitative and quantitative analysis of fecal stanols in the oyster Crassostrea gigas using either single or a combination of lipid purification steps on silica gel or aminopropyl bonded silica gel (NH2) or a washing step. Among the three analytical pathways compared, the two including water extraction or NH2 purification did not lead to higher recoveries and decreased repeatabilities of extractions compared to the single purification on silica gel. This latter led to similar recoveries (ca. 80%) and repeatabilities (ca. 10%) for both spiked standards (coprostanol and sitostanol). This analytical pathway has been applied to oysters collected in a harvesting area in Brittany (France) where fecal contaminations are important and allowed to quantify eight stanols in oysters. The relative proportions of fecal stanols of these oysters were combined with principal component analysis in order to investigate the usefulness of their stanol fingerprints to record a fecal contamination and to distinguish its source between human, porcine and bovine contaminations. Oysters non-fecally contaminated by Escherichia coli did not present specific stanol fingerprints while oysters fecally contaminated had a bovine fingerprint, suggesting a contamination of these samples by bovine sources. As a consequence, the method developed here allows the use of stanol fingerprints of oysters as a microbial source tracking tool that can be applied to shellfish harvesting areas subjected to fecal contaminations in order to identify the different sources of contamination and improve watershed management. PMID:24771549

  16. Accumulation and elimination profiles of paralytic shellfish poison in the short-necked clam Tapes japonica fed with the toxic dinoflagellate Gymnodinium catenatum.

    PubMed

    Samsur, Mohamad; Takatani, Tomohiro; Yamaguchi, Yasunaga; Sagara, Takefumi; Noguchi, Tamao; Arakawa, Osamu

    2007-02-01

    The paralytic shellfish poison (PSP)-producing dinoflagellate Gymnodinium catenatum (Gc) was fed to the short-necked clam Tapes japonica, and the accumulation, transformation and elimination profiles of PSP were investigated by means of high-performance liquid chromatography with postcolumn fluorescence derivatization (HPLC-FLD). The short-necked clams ingested most of the Gc cells (4 x 10(6) cells) supplied as a bolus at the beginning of the experiment, and accumulated a maximal amount of toxin (181 nmol/10 clams) after 12 hr. The rate of toxin accumulation at that time was 16%, which rapidly decreased thereafter. During the rearing period, a variation in toxin composition, derived presumably from the transformation of toxin analogues in the clams, was observed, including a reversal of the ratio of C2 to C1, and the appearance of carbamate (gonyautoxin (GTX) 2, 3) and decarbamoyl (dc) derivatives (decarbamoylsaxitoxin (dcSTX) and dcGTX2, 3), which were undetectable in Gc cells. The total amount of toxin contained in clams and residue (remaining Gc cells and/or excrement in the rearing tank) gradually declined, and only about 1% of the supplied toxin was detected at the end of the experiment. PMID:17370612

  17. Single-laboratory validation of a refined AOAC HPLC method 2005.06 for oysters, cockles, and clams in U.K. shellfish.

    PubMed

    Turner, Andrew D; Hatfield, Robert G; Rapkova-Dhanji, Monika; Norton, Deirdre M; Algoet, Myriam; Lees, David N

    2010-01-01

    In 2009, a refined HPLC method based on AOAC Official Method 2005.06 was developed and validated for the determination of paralytic shellfish poisoning (PSP) in mussels. A single-laboratory validation study of this method was undertaken here for the analysis of PSP toxins in oysters, cockles, clams, and razor clams. The method was characterized for selectivity, sensitivity, linearity, precision, repeatability, recovery, ruggedness, and uncertainty of measurement. Validation data were utilized to determine method performance characteristics for non-mussel bivalves for all commercially available certified reference toxins, extending the method to dcNEO and dcGTX2,3, where available. A period of parallel testing of oysters, cockles, and clams enabled a comparison of sample toxicities obtained using mouse bioassay (MBA) and HPLC methodologies, although only a very low number of PSP-positive samples were obtained through the United Kingdom official control monitoring program. Results from the MBA and HPLC methods were well-correlated for PSP-negative samples, but the low number of naturally contaminated PSP-positive samples has prevented any comparative statistical assessment of method performance for non-mussels between the two official methods. However, some evidence for potentially significant differences in total saxitoxin equivalents obtained by the two methods in some species has highlighted the need for further comparative testing in non-mussel samples to be conducted prior to implementation of the HPLC method in routine official control monitoring programs. PMID:21140661

  18. A Feedback Mechanism to Control Apoptosis Occurs in the Digestive Gland of the Oyster Crassostrea gigas Exposed to the Paralytic Shellfish Toxins Producer Alexandrium catenella

    PubMed Central

    Rolland, Jean-Luc; Medhioub, Walid; Vergnes, Agnes; Abi-khalil, Celina; Savar, Véronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed

    2014-01-01

    To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in caspase-3/7 activity and normal percentage of apoptotic cells in this tissue. Taken together, these results suggest a feedback mechanism, which may occur in the digestive gland where BI.1 could play a key role in preventing the induction of apoptosis by PSTs. Moreover, the expression of CYP1A, Bax and BI.1 were found to be significantly correlated to the occurrence of natural toxic events, suggesting that the expression of these genes together could be used as biomarker to assess the biological responses of oysters to stress caused by PSTs. PMID:25257788

  19. Influence of Environmental Factors on the Paralytic Shellfish Toxin Content and Profile of Alexandrium catenella (Dinophyceae) Isolated from the Mediterranean Sea

    PubMed Central

    Laabir, Mohamed; Collos, Yves; Masseret, Estelle; Grzebyk, Daniel; Abadie, Eric; Savart, Véronique; Sibat, Manoella; Amzil, Zouher

    2013-01-01

    Laboratory experiments were designed to study the toxin content and profile of the Alexandrium catenella strain ACT03 (isolated from Thau Lagoon, French Mediterranean) in response to abiotic environmental factors under nutrient-replete conditions. This dinoflagellate can produce various paralytic shellfish toxins with concentrations ranging from 2.9 to 50.3 fmol/cell. The toxin profile was characterized by carbamate toxins (GTX3, GTX4 and GTX5) and N-sulfocarbamoyl toxins (C1, C2, C3 and C4). C2 dominated at 12–18 °C, but only for salinities ranging from 10 to 25 psu, whereas GTX5 became dominant at temperatures ranging from 21 to 30 °C at almost all salinities. There was no significant variation in the cellular toxin amount from 18 °C to 27 °C for salinities ranging between 30 and 40 psu. At salinities of 10 to 25 psu, the toxin concentrations always remained below 20 fmol/cell. Toxin content was stable for irradiance ranging from 10 to 70 μmol photons/m2/s then slightly increased. Overall, the toxin profile was more stable than the toxin content (fmol/cell), except for temperature and/or salinity values different from those recorded during Alexandrium blooms in Thau Lagoon. PMID:23676417

  20. Preparation of Calibration Standards of N1-H Paralytic Shellfish Toxin Analogues by Large-Scale Culture of Cyanobacterium Anabaena circinalis (TA04)

    PubMed Central

    Watanabe, Ryuichi; Suzuki, Toshiyuki; Oshima, Yasukatsu

    2011-01-01

    Mouse bioassay is the official testing method to quantify paralytic shellfish toxins (PSTs) in bivalves. A number of alternative analytical methods have been reported. Some methods have been evaluated by a single laboratory validation. Among the different types of methods, chemical analyses are capable of identifying and quantifying the toxins, however a shortage of the necessary calibration standards hampers implementation of the chemical analyses in routine monitoring of PSTs in bivalves. In our present study, we studied preparation of major PST analogues as calibrants by large-scale cultivation of toxic freshwater cyanobacteria Anabaena circinalis TA04. The cells were steadily grown in 10 L bottle for 28 days. The primary N1-H toxins, C1/C2, were produced at a concentration of 1.3 ±0.1 μmol/L. The intracellular and extracellular toxins occupied 80% and 20%, respectively. Over 220 μmol of the toxins was obtained from approximately 200 L of the culture over six months, demonstrating that it is sufficient to prepare saxitoxin analogues. The toxins were chemically converted to six N1-H analogues. Preparation of the analogues was carried out at relatively high yields (50–90%). The results indicate that our preparation method is useful to produce N1-H toxins. In our present study, detailed conditions for preparation of one of the rare N1-H analogues, gonyautoxin-5, were investigated. PMID:21556170

  1. Comparison of paralytic shellfish poisoning toxin between carnivorous crabs (Telmessus acutidens and Charybdis japonica) and their prey mussel (Mytilus galloprovincialis) in an inshore food chain.

    PubMed

    Oikawa, Hiroshi; Fujita, Tsuneo; Saito, Ken; Watabe, Shugo; Satomi, Masataka; Yano, Yutaka

    2004-05-01

    Paralytic shellfish poisoning toxin in two shore crab species, Telmessus acutidens and Charybdis japonica, were compared with the toxin in the prey mussel Mytilus galloprovincialis and causative dinoflagellates Alexandrium tamarense, all having been collected at Onahama, Fukushima Prefecture, in the northern part of Japan. When the toxicities were detected in mussels by mouse bioassays, 73.7% of the sampled T. acutidens were toxic in the hepatopancreas. T. acutidens has been found to become toxic for three years, therefore, it can be concluded that the crab commonly and repeatedly accumulate the toxins via the food chain at Onahama. C. japonica was also expected to be a possible vector species, because small quantities of the toxins were detected in eight specimens of the crab by HPLC analysis. By the comparison of the toxin profiles in the dinoflagellates, mussels and the crab T. acutidens, reductive conversions of GTX1 and GTX4 were observed when the toxins passed through the three species in the food chain. But increases of STX and neoSTX by further reductive process were not observed in the crab. The absence of the STX group toxins in the crab suggests that the crab eliminates the toxin before such reductive process occur. PMID:15109892

  2. Two simple models for accounting mussel contamination with diarrhoetic shellfish poisoning toxins at Aveiro lagoon: Control by rainfall and atmospheric forcing

    NASA Astrophysics Data System (ADS)

    Vale, Paulo

    2012-02-01

    At Aveiro lagoon (Portuguese northwest coast) bivalve contamination with diarrhoetic shellfish poisoning toxins (DSTs), okadaic acid (OA) and dinophysistoxin-2 (DTX2), is a recurrent annual phenomenon seriously affecting seafood safety. The influence of meteorological parameters was studied to understand accumulation of DSTs in mussels, related to the blooming of the causative toxic microalgae, belonging to genus Dinophysis. Two simplified models were useful in predicting the accumulation of DSTs in blue mussels from this lagoon. Either the May river drainage or the rainfall accumulated from January through May could adequately predict the severity of OA accumulated from predation upon Dinophysis acuminata during June/July. In both cases a linear relationship was obtained, with correlation coefficients of 0.85 or greater. Winds with a west direction favour coastal concentration of Dinophysis acuta in Aveiro region. Both OA and DTX2 contamination increased exponentially in September/October with the cumulative number of days with W-wind orientation in the preceding August (correlation coefficients greater than 0.92). This relationship was attributed to the quadratic effect of wind stress on surface currents. August is a transitional month, when the continental runoff effect upon Dinophysis acuminata can still be observed and Dinophysis acuta advection may be promoted by westerly winds occurring in July. The frequency of periods with northerly winds in July can halt accumulation of toxins derived from Dinophysis acuta.

  3. In-house validation of a liquid chromatography tandem mass spectrometry method for the analysis of lipophilic marine toxins in shellfish using matrix-matched calibration

    PubMed Central

    van Olst, Erik H. W.; Mulder, Patrick P. J.; de Boer, Jacob

    2010-01-01

    A liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the quantitative analysis of lipophilic marine toxins in shellfish extracts (mussel, oyster, cockle and clam) was validated in-house using European Union (EU) Commission Decision 2002/657/EC as a guideline. The validation included the toxins okadaic acid (OA), yessotoxin (YTX), azaspiracid-1 (AZA1), pectenotoxin-2 (PTX2) and 13-desmethyl spirolide-C (SPX1). Validation was performed at 0.5, 1 and 1.5 times the current EU permitted levels, which are 160 µg kg-1 for OA, AZA1 and PTX2 and 1,000 µg kg-1 for YTX. For SPX1, 400 µg kg-1 was chosen as the target level as no legislation has been established yet for this compound. The method was validated for determination in crude methanolic shellfish extracts and for extracts purified by solid-phase extraction (SPE). Extracts were also subjected to hydrolysis conditions to determine the performance of the method for OA and dinophysistoxin esters. The toxins were quantified against a set of matrix-matched standards instead of standard solutions in methanol. To save valuable standard, methanolic extract instead of the homogenate was spiked with the toxin standard. This was justified by the fact that the extraction efficiency is high for all relevant toxins (above 90%). The method performed very well with respect to accuracy, intraday precision (repeatability), interday precision (within-laboratory reproducibility), linearity, decision limit, specificity and ruggedness. At the permitted level the accuracy ranged from 102 to 111%, the repeatability from 2.6 to 6.7% and the reproducibility from 4.7 to 14.2% in crude methanolic extracts. The crude extracts performed less satisfactorily with respect to the linearity (less than 0.990) and the change in LC-MS/MS sensitivity during the series (more than 25%). SPE purification resulted in greatly improved linearity and signal stability during the series. Recently the European Food Safety Authority (EFSA

  4. Partitioning of paralytic shellfish toxins in sub-cellular fractions of the digestive gland of the cockle Cerastoderma edule: Changes under post-bloom natural conditions.

    PubMed

    Botelho, Maria João; Raimundo, Joana; Vale, Carlos; Ferreira, João Gomes

    2014-06-01

    Concentrations of paralytic shellfish toxins (C1+2, B1, dcGTX2+3, dcSTX, GTX2+3 and STX) were determined by LC-FLD in composite samples of digestive glands of the cockle Cerastoderma edule and in each sub-cellular particulate fractions obtained after differential centrifugation (nuclei+debris, mitochondria, lysosomes and microsomes). The specimens were sampled during the exposure to a bloom of Gymnodinium catenatum (day 0) and in the subsequent 8, 12, 14, 19, 21 and 25 days under natural depuration conditions. Toxin profiles of digestive glands were dominated by C1+2 followed by B1 and dcGTX2+3, although the proportion between C1+2 and B1 contents decreased with the time, indicating a slower elimination of B1. All toxins, except GTX2+3 and STX, were quantified in the four sub-cellular fractions. The content of the quantified toxins decreased most markedly in nuclei+debris and microsomal fractions, during the first eight and 12 days, respectively. Conversely, different patterns were observed among toxins in mitochondrial and lysosomal fractions. The less accentuated decreases of dcGTX2+3 and dcSTX contents in the mitochondrial fraction may have resulted from the conversion of other toxins, like C1+2 and B1, associated with enzymatic activities in that fraction. The largest discrepancy was registered in lysosomal fraction for B1, since its content increased after eight days of post-bloom conditions. Input of B1 may come from the conversion of other toxins, like the abundant B2 and C1+2. These transformations are associated to the major role of lysosomes in the intra-cellular digestive process of materials acquired through vesicular transport. PMID:24736027

  5. The interaction of human microbial pathogens, particulate material and nutrients in estuarine environments and their impacts on recreational and shellfish waters.

    PubMed

    Malham, Shelagh K; Rajko-Nenow, Paulina; Howlett, Eleanor; Tuson, Karen E; Perkins, Tracy L; Pallett, Denise W; Wang, Hui; Jago, Colin F; Jones, Davey L; McDonald, James E

    2014-09-20

    Anthropogenic activities have increased the load of faecal bacteria, pathogenic viruses and nutrients in rivers, estuaries and coastal areas through point and diffuse sources such as sewage discharges and agricultural runoff. These areas are used by humans for both commercial and recreational activities and are therefore protected by a range of European Directives. If water quality declines in these zones, significant economic losses can occur. Identifying the sources of pollution, however, is notoriously difficult due to the ephemeral nature of discharges, their diffuse source, and uncertainties associated with transport and transformation of the pollutants through the freshwater-marine interface. Further, significant interaction between nutrients, microorganisms and particulates can occur in the water column making prediction of the fate and potential infectivity of human pathogenic organisms difficult to ascertain. This interaction is most prevalent in estuarine environments due to the formation of flocs (suspended sediment) at the marine-freshwater interface. A range of physical, chemical and biological processes can induce the co-flocculation of microorganisms, organic matter and mineral particles resulting in pathogenic organisms becoming potentially protected from a range of biotic (e.g. predation) and abiotic stresses (e.g. UV, salinity). These flocs contain and retain macro- and micro- nutrients allowing the potential survival, growth and transfer of pathogenic organisms to commercially sensitive areas (e.g. beaches, shellfish harvesting waters). The flocs can either be transported directly to the coastal environment or can become deposited in the estuary forming cohesive sediments where pathogens can survive for long periods. Especially in response to storms, these sediments can be subsequently remobilised releasing pulses of potential pathogenic organisms back into the water column leading to contamination of marine waters long after the initial

  6. Profiles of paralytic shellfish toxins in bivalves of low and elevated toxicities following exposure to Gymnodinium catenatum blooms in Portuguese estuarine and coastal waters.

    PubMed

    Botelho, Maria João; Vale, Carlos; Ferreira, João Gomes

    2015-11-01

    Profiles of paralytic shellfish toxins (PSTs) were examined in 405 composite samples of Mytilus spp., Cerastoderma edule, Donax trunculus and Spisula solida collected between 2007 and 2012 from natural production areas in two estuaries (Aveiro and Mondego), two coastal lagoons (Óbidos and Formosa), and three open coastal areas (Aguda, Comporta and Culatra). Toxin concentrations were obtained from the biotoxin monitoring programme database. Episodes of PST toxicity in Portugal have been associated with Gymnodinium catenatum blooms. Toxin profiles for each species showed no trend over the surveyed years. In general, profiles differ only slightly among areas, except for Óbidos. However, toxin profiles in bivalves varied between low and elevated toxicities, corresponding to below and above the PST regulatory limit, respectively. The ratio R1=(C1+2):B1, which were the main toxins produced by G. catenatum cells, decreased considerably between elevated and low toxicity cockles, indicating the elimination of C1+2 or conversion of compounds into B1. R2=[(dcSTX)+(dcGTX2+3)]:[(C1+2)+(B1)], which represents the ratio of minor to major toxins in G. catenatum cells, increased substantially in wedge clams (D. trunculus) of low toxicity and less markedly in cockles (C. edule) and mussels (Mytilus spp.). These differences are interpreted as the predominance of a biotransformation phase after exposure to the algal bloom. The toxin profile of surf clams (S. solida) was dominated by decarbamoyl compounds, reflecting intense biotransformation during exposure to blooms. The higher ratio R2 in low toxicity samples suggests that elimination of the produced decarbamoyl toxins was slower than biotransformation. PMID:25616737

  7. Contrasting Physiological Responses of Two Populations of the Razor Clam Tagelus dombeii with Different Histories of Exposure to Paralytic Shellfish Poisoning (PSP)

    PubMed Central

    Navarro, Jorge M.; González, Katerina; Cisternas, Barbara; López, Jorge A.; Chaparro, Oscar R.; Segura, Cristian J.; Córdova, Marco; Suárez-Isla, Benjamín; Fernandez-Reiriz, María J.; Labarta, Uxio

    2014-01-01

    This study describes the physiological performance of two populations of the razor clam Tagelus dombeii from two geographic areas with different histories of exposure to paralytic shellfish poisoning (PSP) linked to the toxic dinoflagellate Alexandrium catenella. Clams from Melinka-Aysén, which are frequently exposed to PSP, were not affected by the presence of toxins in the diet. However, clams from Corral-Valdivia, which have never been exposed to PSP, exhibited significantly reduced filtration activity and absorption, affecting the energy allocated to scope for growth (SFG). Ammonia excretion and oxygen uptake were not affected significantly by the presence of A. catenella in the diet. Measurements of energy acquisition and expenditure were performed during a 12-day intoxication period. According to three-way repeated measure ANOVAs, the origin of the clams had a highly significant effect on all physiological variables, and the interaction between diet and origin was significant for the clearance and absorption rates and for the scope for growth. The scope for growth index showed similar positive values for both the toxic and non-toxic individuals from the Melinka-Aysén population. However, it was significantly reduced in individuals from Corral-Valdivia when exposed to the diet containing A. catenella. The absence of differences between the physiological response of the toxic and non-toxic clams from Melinka-Aysén may be related to the frequent presence of A. catenella in the environment, indicating that this bivalve does not suffer negative consequences from PSP. By contrast, A. catenella has a negative effect on the physiological performance, primarily on the energy gained from the environment, on T. dombeii from Corral-Valdivia. This study supports the hypothesis that the history of PSP exposure plays an important role in the physiological performance and fitness of filter feeding bivalves. PMID:25153329

  8. High Specificity of a Quantitative PCR Assay Targeting a Saxitoxin Gene for Monitoring Toxic Algae Associated with Paralytic Shellfish Toxins in the Yellow Sea

    PubMed Central

    Gao, Yan; Murray, Shauna A.; Chen, Jian-Hua; Kang, Zhen-Jun; Zhang, Qing-Chun; Kong, Fan-Zhou; Zhou, Ming-Jiang

    2015-01-01

    The identification of core genes involved in the biosynthesis of saxitoxin (STX) offers a great opportunity to detect toxic algae associated with paralytic shellfish toxins (PST). In the Yellow Sea (YS) in China, both toxic and nontoxic Alexandrium species are present, which makes it a difficult issue to specifically monitor PST-producing toxic algae. In this study, a quantitative PCR (qPCR) assay targeting sxtA4, a domain in the sxt gene cluster that encodes a unique enzyme involved in STX biosynthesis, was applied to analyze samples collected from the YS in spring of 2012. The abundance of two toxic species within the Alexandrium tamarense species complex, i.e., A. fundyense and A. pacificum, was also determined with TaqMan-based qPCR assays, and PSTs in net-concentrated phytoplankton samples were analyzed with high-performance liquid chromatography coupled with a fluorescence detector. It was found that the distribution of the sxtA4 gene in the YS was consistent with the toxic algae and PSTs, and the quantitation results of sxtA4 correlated well with the abundance of the two toxic species (r = 0.857). These results suggested that the two toxic species were major PST producers during the sampling season and that sxtA-based qPCR is a promising method to detect toxic algae associated with PSTs in the YS. The correlation between PST levels and sxtA-based qPCR results, however, was less significant (r = 0.552), implying that sxtA-based qPCR is not accurate enough to reflect the toxicity of PST-producing toxic algae. The combination of an sxtA-based qPCR assay and chemical means might be a promising method for monitoring toxic algal blooms. PMID:26231652

  9. Determining the Advantages, Costs, and Trade-Offs of a Novel Sodium Channel Mutation in the Copepod Acartia hudsonica to Paralytic Shellfish Toxins (PST)

    PubMed Central

    Finiguerra, Michael; Avery, David E.; Dam, Hans G.

    2015-01-01

    The marine copepod Acartia hudsonica was shown to be adapted to dinoflagellate prey, Alexandrium fundyense, which produce paralytic shellfish toxins (PST). Adaptation to PSTs in other organisms is caused by a mutation in the sodium channel. Recently, a mutation in the sodium channel in A. hudsonica was found. In this study, we rigorously tested for advantages, costs, and trade-offs associated with the mutant isoform of A. hudsonica under toxic and non-toxic conditions. We combined fitness with wild-type: mutant isoform ratio measurements on the same individual copepod to test our hypotheses. All A. hudsonica copepods express both the wild-type and mutant sodium channel isoforms, but in different proportions; some individuals express predominantly mutant (PMI) or wild-type isoforms (PWI), while most individuals express relatively equal amounts of each (EI). There was no consistent pattern of improved performance as a function of toxin dose for egg production rate (EPR), ingestion rate (I), and gross growth efficiency (GGE) for individuals in the PMI group relative to individuals in the PWI expression group. Neither was there any evidence to indicate a fitness benefit to the mutant isoform at intermediate toxin doses. No clear advantage under toxic conditions was associated with the mutation. Using a mixed-diet approach, there was also no observed relationship between individual wild-type: mutant isoform ratios and among expression groups, on both toxic and non-toxic diets, for eggs produced over three days. Lastly, expression of the mutant isoform did not mitigate the negative effects of the toxin. That is, the reductions in EPR from a toxic to non-toxic diet for copepods were independent of expression groups. Overall, the results did not support our hypotheses; the mutant sodium channel isoform does not appear to be related to adaptation to PST in A. hudsonica. Other potential mechanisms responsible for the adaptation are discussed. PMID:26075900

  10. High Specificity of a Quantitative PCR Assay Targeting a Saxitoxin Gene for Monitoring Toxic Algae Associated with Paralytic Shellfish Toxins in the Yellow Sea.

    PubMed

    Gao, Yan; Yu, Ren-Cheng; Murray, Shauna A; Chen, Jian-Hua; Kang, Zhen-Jun; Zhang, Qing-Chun; Kong, Fan-Zhou; Zhou, Ming-Jiang

    2015-10-01

    The identification of core genes involved in the biosynthesis of saxitoxin (STX) offers a great opportunity to detect toxic algae associated with paralytic shellfish toxins (PST). In the Yellow Sea (YS) in China, both toxic and nontoxic Alexandrium species are present, which makes it a difficult issue to specifically monitor PST-producing toxic algae. In this study, a quantitative PCR (qPCR) assay targeting sxtA4, a domain in the sxt gene cluster that encodes a unique enzyme involved in STX biosynthesis, was applied to analyze samples collected from the YS in spring of 2012. The abundance of two toxic species within the Alexandrium tamarense species complex, i.e., A. fundyense and A. pacificum, was also determined with TaqMan-based qPCR assays, and PSTs in net-concentrated phytoplankton samples were analyzed with high-performance liquid chromatography coupled with a fluorescence detector. It was found that the distribution of the sxtA4 gene in the YS was consistent with the toxic algae and PSTs, and the quantitation results of sxtA4 correlated well with the abundance of the two toxic species (r=0.857). These results suggested that the two toxic species were major PST producers during the sampling season and that sxtA-based qPCR is a promising method to detect toxic algae associated with PSTs in the YS. The correlation between PST levels and sxtA-based qPCR results, however, was less significant (r=0.552), implying that sxtA-based qPCR is not accurate enough to reflect the toxicity of PST-producing toxic algae. The combination of an sxtA-based qPCR assay and chemical means might be a promising method for monitoring toxic algal blooms. PMID:26231652

  11. Implication of brevetoxin B1 and PbTx-3 in neurotoxic shellfish poisoning in New Zealand by isolation and quantitative determination with liquid chromatography-tandem mass spectrometry.

    PubMed

    Nozawa, Akira; Tsuji, Kuniro; Ishida, Hitoshi

    2003-07-01

    Brevetoxin B1 (BTX-B1) was isolated from Austrovenus stutchburyi following the 1992-1993 outbreak of neurotoxic shellfish poisoning (NSP) in New Zealand. We report here the first isolation of PbTx-3 from the same shellfish and the development of a procedure for quantitative determination of PbTx-3 and BTX-B1. PbTx-3 was isolated by chromatography on columns of SiO2, ODS, and LH-20, followed by reverse-phase HPLCs. In mass spectrometry (MS) with an electrospray ionization (ESI) interface operating in the positive or negative ion mode, the abundant protonated ion [M+H]+ of PbTx-3 (m/z 897) and the de-sodiated ion [M-Na]- of BTX-B1 (m/z 1016) were generated, respectively. These served as precursor ions for collision-induced dissociation, and the product ions of m/z 725 from PbTx-3 and m/z 80 from BTX-B1 were identified, allowing unambiguous confirmation of these toxins by selected reaction monitoring liquid chromatography-tandem mass spectrometry (SRM LC-MS/MS) analysis. The determination limits were 0.4 and 2 ng/g for BTX-B1 and PbTx-3 at a signal-to-noise ratio of five, respectively. This LC-MS/MS method was successfully applied to determine BTX-B1 and PbTx-3 in the NSP-associated toxic shellfish. BTX-B1 was found in both A. stutchburyi and Perna canaliculus, but not in Crassostrea gigas, while PbTx-3 was found in all three. PMID:12893066

  12. Metal-organic framework UiO-66 modified magnetite@silica core-shell magnetic microspheres for magnetic solid-phase extraction of domoic acid from shellfish samples.

    PubMed

    Zhang, Wenmin; Yan, Zhiming; Gao, Jia; Tong, Ping; Liu, Wei; Zhang, Lan

    2015-06-26

    Fe3O4@SiO2@UiO-66 core-shell magnetic microspheres were synthesized and characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, vibrating sample magnetometry, nitrogen adsorption porosimetry and zeta potential analyzer. The synthesized Fe3O4@SiO2@UiO-66 microspheres were first used for magnetic solid-phase extraction (MSPE) of domoic acid (DA) in shellfish samples. Combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), a fast, simple and sensitive method for the determination of DA was established successfully. Under the optimized conditions, the developed method showed short analysis time, good linearity (r(2) = 0.9990), low limit of detection (1.45 pg mL(-1); S/N = 3:1), low limit of quantification (4.82 pg mL(-1); S/N = 10:1), and good extraction repeatability (RSD ≤ 5.0%; n = 5). Real shellfish samples were processed using the developed method, and trace level of DA was detected. The results demonstrate that Fe3O4@SiO2@UiO-66 core-shell magnetic microspheres are the promising sorbents for rapid and efficient extraction of polar analytes from complex biological samples. PMID:25997847

  13. Development of the fecal coliform total maximum daily load using Loading Simulation Program C++ and tidal prism model in estuarine shellfish growing areas: a case study in the Nassawadox coastal embayment, Virginia.

    PubMed

    Shen, Jian; Sun, Shucun; Wang, Taiping

    2005-01-01

    In this study, a linked model system including the Loading Simulation Program C++ (LSPC) and the tidal prism water quality model (TPWQM) was proposed as an alternative tool for total maximum daily load (TMDL) studies. The feasibility of the model system was tested by a case study in the Nassawadox Creek, a Virginia tidal water shellfish growing area. The watershed model, driven by hourly precipitation, simulates hydrology and fecal coliform accumulation and transport processes in the watershed. The simulated surface runoff and subsurface flow as well as fecal coliform loads from the watershed are discharged to the tidal creek. The tidal prism model simulates fecal coliform transport in the Creek. The model results demonstrate the effectiveness in simulating hydrology and fecal coliform concentration in the watershed and its embayment. A series of sensitivity runs was conducted to estimate the load reduction necessary for fecal coliform concentration to meet the water quality standards. The model application to the Nassawadox Creek indicates that the model system is useful in developing fecal coliform TMDLs for estuarine shellfish growing areas. PMID:16134369

  14. Analysis of diarrhetic shellfish poisoning toxins and pectenotoxin-2 in the bottlenose dolphin (Tursiops truncatus) by liquid chromatography-tandem mass spectrometry.

    PubMed

    Wang, Zhihong; Broadwater, Margaret H; Ramsdell, John S

    2015-10-16

    Toxins produced by harmful algae are associated with detrimental health effects and mass mortalities of marine mammals. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is generally used to confirm the presence of algal toxins in marine mammals. Sample preparation and LC-MS/MS methods for the determination of three diarrhetic shellfish poisoning (DSP) toxins (okadaic acid, OA; dinophysistoxin-1, DTX1; dinophysistoxin-2, DTX2) and pectenotoxin-2 (PTX2) in bottlenose dolphin (Tursiops truncatus) urine and tissue samples were evaluated using spike-and-recovery tests. Sample clean-up with either reversed-phase silica or polymeric solid-phase extraction (SPE) reduced interference of sample matrices and improved toxin recoveries, with polymeric SPE showing higher sample loading capacity. LC separation on Xbridge C18 columns using acetonitrile/water gradient elutions with ammonia as the additive was chosen for its high detectivity and sensitivity in the MS detection of DSP toxins in negative ion mode. The retention times of OA, DTX1, and DTX2, separated as negative ions, increased with LC column temperature while the retention time of PTX2, separated as the neutral molecule, was weakly affected. At the same column temperature, retention times of OA, DTX1, and DTX2 gradually increased as the mobile phases aged while the retention time of PTX2 remained unchanged; higher column temperatures resulted in a greater increase in the retention time of each DSP toxin with mobile phase aging. Average recoveries of the 4 toxins in bottlenose dolphin samples ranged from 80% to 130% with relative standard deviations of less than 15% using the LC mobile phases prepared within one week at a column temperature of 30°C or 40°C. The preferred column temperature was 30°C, as the retention times of DSP toxins were less affected by mobile phase aging at this temperature. The limit of detection of each toxin analyzed in bottlenose dolphin samples was 2.8 ng/g or less in tissue

  15. Paralytic shellfish toxins in the sea scallop Placopecten magellanicus on Georges Bank: Implications for an offshore roe-on and whole scallop fishery

    NASA Astrophysics Data System (ADS)

    DeGrasse, Stacey; Vanegas, Camilo; Conrad, Stephen

    2014-05-01

    To protect public health from the potential risk of paralytic shellfish poisoning (PSP) in sea scallops, Placopecten magellanicus, from the Atlantic offshore U.S. waters of Georges Bank, harvesting of roe-on or whole scallops is banned. Only adductor muscles may be sold if harvested from Georges Bank, Gulf of Maine, or the PSP closure areas as far west as 71° West Longitude. Given the limited toxicity data available for sea scallops from this region both prior to and subsequent to implementation of this management strategy, this study sought a more extensive spatial and temporal evaluation of sea scallop gonad and viscera toxicities that would inform management decisions related to the roe-on and whole scallop fishery. Both overall toxicity and toxin composition were measured for sea scallop gonads and viscera collected from 232 stations in 2007 and 23 in 2010. Overall toxicity was assessed using two screening methods: field-deployable Jellett Rapid Tests (JRT) and quantitative, laboratory-based receptor binding assays (in 2007). Additionally, a quantitative liquid chromatography with fluorescence detection (LC-FD) method was used to determine toxin composition and overall toxicity (in 2010). The at-sea qualitative JRT screening tool results, whereby a positive indicated the sample contained at least 40 μg saxitoxin (STX) equivalents 100 g-1, were often inconsistent with results obtained using the quantitative methods. Sea scallop viscera toxicity represented the majority of toxin load in the organism and was often in excess of the regulatory guidance level. Sea scallop gonads accounted for a small percentage of total toxicity, but at times reached unsafe levels. Toxin composition in both the gonads and viscera was dominated by STX and gonyautoxin 2/3, as has been reported in previous studies. No predictive indices of gonad toxicity were found. Results at this time do not support a roe-on or whole scallop fishery on Georges Bank. While access restrictions to

  16. Improving early detection of exotic or emergent oyster diseases in France: identifying factors associated with shellfish farmer reporting behaviour of oyster mortality.

    PubMed

    Lupo, C; Osta Amigo, A; Mandard, Y V; Peroz, C; Renault, T

    2014-09-01

    Farmers' vigilance is essential for the detection of epidemics, including potential emerging diseases, in marine shellfish. A field study was conducted to investigate oyster farmers' reporting practices and behaviour, and to identify factors influencing the reporting process of oyster mortality, with the ultimate aim of improving early detection of unexplained oyster mortality outbreaks. A retrospective case-control study of oyster farmers from Charente-Maritime (France) was designed, based on interviews with 27 non-reporting and 89 reporting farmers, further split into 40 formerly-reporting and 49 currently-reporting farmers. Information about farmer and farm characteristics, farming practices, farm health history and related financial compensation on the farm, knowledge of the mortality reporting system and reporting behaviour was collected. Sampling design was considered in the calculations and farmers' reporting behaviour was modelled using an ordinal logistic regression (continuation-ratio model). Notification procedures were fairly well known among farmers and the reporting system was well accepted overall. Nevertheless, a lack of awareness of the aims of the reporting system was revealed, which contributed to late reporting. Factors identified as driving a farmer's decision to report oyster mortality concerned their lack of awareness of mortality reporting (production type, farm size, location of the production cycle, accessibility of the leasing grounds) and willingness to report (possibility and extent of financial compensation, a feeling of not being involved, whether it was first year of reporting). Overall classification performance of the model built in this study was 64%. In particular, financial compensation for oyster production losses appeared to be a clear incentive for reporting, but was countered by a habituation effect combined with a lack of awareness of the aims of the reporting system: oyster farmers looking for benefits for themselves in

  17. Chelal Characteristics and Foraging Behaviour of the Blue Crab Callinectes sapidusRathbun

    NASA Astrophysics Data System (ADS)

    Seed, R.; Hughes, R. N.

    1997-02-01

    This paper describes the morphological and mechanical characteristics of the chelae of Callinectes sapidus, together with the predation techniques, handling times and prey size selection of this voracious predator when presented with marsh mussels, Geukensia demissa, or fiddler crabs, Uca pugilator, in laboratory aquaria. Callinectes sapidusis heterochelous but differences in claw size and mechanical advantage between male and female crabs are statistically indistinguishable. Handling times for mussels and fiddler crabs increased steeply with prey size. Fiddler crabs are intrinsically more profitable than mussels, but the relative costs of capturing mobile prey, or excavating mussels, in natural populations is unknown. Previous laboratory experiments investigating the key stimuli used by C. sapiduswhen selecting prey are reviewed, and their results are compared with behaviour predicted by optimal foraging theory. It is concluded that crabs respond to the strongest stimuli received from the prey. Items were rejected after a given persistence time if the attack proved unsuccessful. Persistence time, however, was adjusted through experience to expectations of local prey quality and availability. The integrated result of this key-stimulus mechanism will be a close match to diets predicted by other behavioural models, including that based on optimal foraging theory.

  18. Hemigrapsus sanguineus in Long Island salt marshes: experimental evaluation of the interactions between an invasive crab and resident ecosystem engineers.

    PubMed

    Peterson, Bradley J; Fournier, Alexa M; Furman, Bradley T; Carroll, John M

    2014-01-01

    The invasive Asian shore crab, Hemigrapsus sanguineus, has recently been observed occupying salt marshes, a novel environment for this crab species. As it invades this new habitat, it is likely to interact with a number of important salt marsh species. To understand the potential effects of H. sanguineus on this ecosystem, interactions between this invasive crab and important salt marsh ecosystem engineers were examined. Laboratory experiments demonstrated competition for burrows between H. sanguineus and the native fiddler crab, Uca pugilator. Results indicate that H. sanguineus is able to displace an established fiddler crab from its burrow. Feeding experiments revealed that the presence of H. sanguineus has a significantly negative impact on the number as well as the biomass of ribbed mussels (Geukensia demissa) consumed by the green crab, Carcinus maenas, although this only occurred at high predator densities. In addition, when both crabs foraged together, there was a significant shift in the size of mussels consumed. These interactions suggests that H. sanguineus may have long-term impacts and wide-ranging negative effects on the saltmarsh ecosystem. PMID:25071995

  19. Foundation species' overlap enhances biodiversity and multifunctionality from the patch to landscape scale in southeastern United States salt marshes

    PubMed Central

    Angelini, Christine; van der Heide, Tjisse; Griffin, John N.; Morton, Joseph P.; Derksen-Hooijberg, Marlous; Lamers, Leon P. M.; Smolders, Alfons J. P.; Silliman, Brian R.

    2015-01-01

    Although there is mounting evidence that biodiversity is an important and widespread driver of ecosystem multifunctionality, much of this research has focused on small-scale biodiversity manipulations. Hence, which mechanisms maintain patches of enhanced biodiversity in natural systems and if these patches elevate ecosystem multifunctionality at both local and landscape scales remain outstanding questions. In a 17 month experiment conducted within southeastern United States salt marshes, we found that patches of enhanced biodiversity and multifunctionality arise only where habitat-forming foundation species overlap—i.e. where aggregations of ribbed mussels (Geukensia demissa) form around cordgrass (Spartina alterniflora) stems. By empirically scaling up our experimental results to the marsh platform at 12 sites, we further show that mussels—despite covering only approximately 1% of the marsh surface—strongly enhance five distinct ecosystem functions, including decomposition, primary production and water infiltration rate, at the landscape scale. Thus, mussels create conditions that support the co-occurrence of high densities of functionally distinct organisms within cordgrass and, in doing so, elevate salt marsh multifunctionality from the patch to landscape scale. Collectively, these findings suggest that patterns in foundation species' overlap drive variation in biodiversity and ecosystem functioning within and across natural ecosystems. We therefore argue that foundation species should be integrated in our conceptual understanding of forces that moderate biodiversity–ecosystem functioning relationships, approaches for conserving species diversity and strategies to improve the multifunctionality of degraded ecosystems. PMID:26136442

  20. Hemigrapsus sanguineus in Long Island salt marshes: experimental evaluation of the interactions between an invasive crab and resident ecosystem engineers

    PubMed Central

    Fournier, Alexa M.; Furman, Bradley T.; Carroll, John M.

    2014-01-01

    The invasive Asian shore crab, Hemigrapsus sanguineus, has recently been observed occupying salt marshes, a novel environment for this crab species. As it invades this new habitat, it is likely to interact with a number of important salt marsh species. To understand the potential effects of H. sanguineus on this ecosystem, interactions between this invasive crab and important salt marsh ecosystem engineers were examined. Laboratory experiments demonstrated competition for burrows between H. sanguineus and the native fiddler crab, Uca pugilator. Results indicate that H. sanguineus is able to displace an established fiddler crab from its burrow. Feeding experiments revealed that the presence of H. sanguineus has a significantly negative impact on the number as well as the biomass of ribbed mussels (Geukensia demissa) consumed by the green crab, Carcinus maenas, although this only occurred at high predator densities. In addition, when both crabs foraged together, there was a significant shift in the size of mussels consumed. These interactions suggests that H. sanguineus may have long-term impacts and wide-ranging negative effects on the saltmarsh ecosystem. PMID:25071995

  1. Foundation species' overlap enhances biodiversity and multifunctionality from the patch to landscape scale in southeastern United States salt marshes.

    PubMed

    Angelini, Christine; van der Heide, Tjisse; Griffin, John N; Morton, Joseph P; Derksen-Hooijberg, Marlous; Lamers, Leon P M; Smolders, Alfons J P; Silliman, Brian R

    2015-07-22

    Although there is mounting evidence that biodiversity is an important and widespread driver of ecosystem multifunctionality, much of this research has focused on small-scale biodiversity manipulations. Hence, which mechanisms maintain patches of enhanced biodiversity in natural systems and if these patches elevate ecosystem multifunctionality at both local and landscape scales remain outstanding questions. In a 17 month experiment conducted within southeastern United States salt marshes, we found that patches of enhanced biodiversity and multifunctionality arise only where habitat-forming foundation species overlap--i.e. where aggregations of ribbed mussels (Geukensia demissa) form around cordgrass (Spartina alterniflora) stems. By empirically scaling up our experimental results to the marsh platform at 12 sites, we further show that mussels--despite covering only approximately 1% of the marsh surface--strongly enhance five distinct ecosystem functions, including decomposition, primary production and water infiltration rate, at the landscape scale. Thus, mussels create conditions that support the co-occurrence of high densities of functionally distinct organisms within cordgrass and, in doing so, elevate salt marsh multifunctionality from the patch to landscape scale. Collectively, these findings suggest that patterns in foundation species' overlap drive variation in biodiversity and ecosystem functioning within and across natural ecosystems.We therefore argue that foundation species should be integrated in our conceptual understanding of forces that moderate biodiversity--ecosystem functioning relationships, approaches for conserving species diversity and strategies to improve the multifunctionality of degraded ecosystems. PMID:26136442

  2. Assessing a bioremediation strategy in a shallow coastal system affected by a fish farm culture--application of GIS and shellfish dynamic models in the Rio San Pedro, SW Spain.

    PubMed

    Silva, C; Yáñez, E; Martín-Díaz, M L; DelValls, T A

    2012-04-01

    An integrated multi-trophic aquaculture assessment for Pacific oyster (Crassostrea gigas) aquaculture as a bioremediation strategy in areas impacted by fish farm effluents in Rio San Pedro was assessed by combining geographic information system with carrying capacity models. Sites of 0.44 km(2) were evaluated considering constraints; physical factors, growth and survival factors, environmental quality factors, water and sediment quality criteria, factor suitability ranges, and Multi-Criteria Evaluation. Isleta and Flamenco are promising sites for oyster production, and Dorada is of marginal interest. Carbon and nitrogen removal from the water by algae and through detritus filtration was estimated. The biodeposition of organic material from longline leases was found to have little negative impact on sediment. The eutrophication results indicate that phytoplankton removal had a positive impact on water quality at the Dorada. This case study quantified the direct profitability and bioremediative environmental service advantages that fish-shellfish farms can have relative to fish monocultures. PMID:22310375

  3. An innovative method based on quick, easy, cheap, effective, rugged, and safe extraction coupled to desorption electrospray ionization-high resolution mass spectrometry for screening the presence of paralytic shellfish toxins in clams.

    PubMed

    Mattarozzi, Monica; Bianchi, Federica; Milioli, Marco; Cavazza, Antonella; Careri, Maria

    2016-01-15

    The capabilities of desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) were tested for screening the presence of some paralytic shellfish toxins in clams. A quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach is proposed for sample clean-up. QuEChERS extraction was optimized by using a full factorial design followed by the multicriteria method of the desirability functions. Quantitation limits in the microgram per kilogram range proved reliability of the method for the detection of the investigated toxins in accordance to the rules laid down by European legislation. The optimized QuEChERS-DESI-HRMS based-method allowed for a rapid reliable screening of the investigated compounds at levels of interest, thus being useful for high-throughput analyses. PMID:26592627

  4. Database of radionuclide measurements in Columbia River water, fish, waterfowl, gamebirds, and shellfish downstream of Hanford`s single-pass production reactors, 1960--1970. Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Thiede, M.E.; Duncan, J.P.

    1994-03-01

    This report is a result of the Hanford Environmental Dose Reconstruction (HEDR) Project. The goal of the HEDR Project is to estimate the radiation dose that individuals could have received from radionuclide emissions since 1944 at the Hanford Site near Richland, Washington. The HEDR Project is conducted by Battelle, Pacific Northwest Laboratories. The time periods of greatest interest to the HEDR study vary depending on the type of environmental media concerned. Concentrations of radionuclides in Columbia River media from 1960--1970 provide the best historical data for validation of the Columbia River pathway computer models. This report provides the historical radionuclide measurements in Columbia River water (1960--1970), fish (1960--1967), waterfowl (1960--1970), gamebirds (1967--1970), and shellfish (1960--1970). Because of the large size of the databases (845 pages), this report is being published on diskette. A diskette of this report is available from the Technical Steering Panel (c/o K. CharLee, Office of Nuclear Waste Management, Department of Ecology, Technical Support and Publication Information Section, P.O. Box 47651, Olympia, Washington 98504-7651).

  5. Enhanced recovery of Arcobacter spp. using NaCl in culture media and re-assessment of the traits of Arcobacter marinus and Arcobacter halophilus isolated from marine water and shellfish.

    PubMed

    Salas-Massó, Nuria; Andree, Karl B; Furones, M Dolors; Figueras, M José

    2016-10-01

    The genus Arcobacter is a relatively poorly known group of bacteria, and the number of new species and sequences from non-culturable strains has increased considerably in recent years. This study investigates whether using media that contain NaCl might help to improve the recovery of Arcobacter spp. from marine environments. To this aim, 62 water and shellfish samples were analysed in parallel, with both a commonly used culture method (enrichment in Arcobacter-CAT broth followed by culture on Blood Agar) and a new one that supplements the Arcobacter-CAT enrichment broth with 2.5% NaCl (w/v) followed by culturing on Marine Agar. The new method yielded ca. 40% more positive samples and provided a higher diversity of known (11 vs. 7) and unknown (7 vs. 2) Arcobacter species. Among the 11 known species recovered, Arcobacter marinus and Arcobacter halophilus were isolated only by this new method. No more strains of these species have been isolated since their original descriptions, both of which were based only on a single strain. In view of that, the phenotypic characteristics of these species are re-evaluated in the present study, using the new strains. Strains of A. halophilus had the same phenotypic profile as the type strain. However, some strains of A. marinus differed from the type strain in that they did not hydrolyse indoxyl-acetate, becoming, therefore, the first Arcobacter species to show a varying ability to hydrolyse indoxyl-acetate. This study shows to what extent a simple variation to the culture media can have a big influence on positive samples and on the community of species recovered. PMID:27282494

  6. Restricting Prey Dispersal Can Overestimate the Importance of Predation in Trophic Cascades

    PubMed Central

    Geraldi, Nathan R.; Macreadie, Peter I.

    2013-01-01

    Predators can affect prey populations and, via trophic cascades, predators can indirectly impact resource populations (2 trophic levels below the predator) through consumption of prey (density-mediated indirect effects; DMIEs) and by inducing predator-avoidance behavior in prey (trait-mediated indirect effects; TMIEs). Prey often employ multiple predator-avoidance behaviors, such as dispersal or reduced foraging activity, but estimates of TMIEs are usually on individual behaviors. We assessed direct and indirect predator effects in a mesocosm experiment using a marine food chain consisting of a predator (toadfish – Opsanus tau), prey (mud crab - Panopeus herbstii) and resource (ribbed mussel – Geukensia demissa). We measured dispersal and foraging activity of prey separately by manipulating both the presence and absence of the predator, and whether prey could or could not disperse into a predator-free area. Consumption of prey was 9 times greater when prey could not disperse, probably because mesocosm boundaries increased predator capture success. Although predator presence did not significantly affect the number of crabs that emigrated, the presence of a predator decreased resource consumption by prey, which resulted in fewer resources consumed for each prey that emigrated in the presence of a predator, and reduced the overall TMIE. When prey were unable to disperse, TMIEs on mussel survival were 3 times higher than the DMIEs. When prey were allowed to disperse, the TMIEs on resource survival increased to 11-times the DMIEs. We found that restricting the ability of prey to disperse, or focusing on only one predator-avoidance behavior, may be underestimating TMIEs. Our results indicate that the relative contribution of behavior and consumption in food chain dynamics will depend on which predator-avoidance behaviors are allowed to occur and measured. PMID:23408957

  7. Zoonotic infections from fish and shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The worldwide development of aquaculture and the worldwide transport of live aquaculture products has, apart from many advantages, also worrisome consequences. Among them is the occurrence and increased recognition of zoonotic disease agents causing epidemics and carrier states in cultured fish and ...

  8. 21 CFR 1240.60 - Molluscan shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the spread of communicable disease from one State or possession to another. (b) All shellstock shall bear a tag that discloses the date and place they were harvested (by State and site), type and...

  9. 21 CFR 1240.60 - Molluscan shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the spread of communicable disease from one State or possession to another. (b) All shellstock shall bear a tag that discloses the date and place they were harvested (by State and site), type and...

  10. 21 CFR 1240.60 - Molluscan shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the spread of communicable disease from one State or possession to another. (b) All shellstock shall bear a tag that discloses the date and place they were harvested (by State and site), type and...

  11. 21 CFR 1240.60 - Molluscan shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the spread of communicable disease from one State or possession to another. (b) All shellstock shall bear a tag that discloses the date and place they were harvested (by State and site), type and...

  12. Comparative concentrations of brevetoxins PbTx-2, PbTx-3, BTX-B1 and BTX-B5 in cockle, Austrovenus stutchburyi, greenshell mussel, Perna canaliculus, and Pacific oyster, Crassostrea gigas, involved neurotoxic shellfish poisoning in New Zealand.

    PubMed

    Ishida, Hitoshi; Nozawa, Akira; Nukaya, Haruo; Tsuji, Kuniro

    2004-06-01

    Previously, we found brevetoxins PbTx-3, BTX-B5 and BTX-B1 in cockle, Austrovenus (A.) stutchburyi, PbTx-2, PbTx-3 and BTX-B1 in Pacific oyster, Crassostrea (C.) gigas and PbTx-3 and BTX-B1 in greenshell mussel, Perna (P.) canaliculus following outbreak of neurotoxic shellfish poisoning (NSP) in New Zealand by isolation and/or liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). In this study, procedures for quantitative determination of PbTx-2 and BTX-B5 were developed and those for PbTx-3 and BTX-B1 were further examined by LC-MS/MS. In mass spectrometry with an electrospray ionization interface operating in the positive or negative ion mode, the protonated ions [M+H]+ of PbTx-2 (m/z 895), [M+H]+ of PbTx-3 (m/z 897), [M-H]- of BTX-B5 (m/z 909), and [M-Na]- of BTX-B1 (m/z 1016) were generated abundantly, when 0.1% formic acid-acetonitrile was used as the mobile phase for column chromatography. The product ions of m/z 877, 725, 111 and 80 from PbTx-2, PbTx-3, BTX-B5 and BTX-B1 were identified, respectively, allowing unambiguous confirmation of these toxins by selective reaction monitoring LC-MS/MS analysis. High levels of PbTx-3 and BTX-B5 were detected in C. gigas, of PbTx-3, BTX-B1 and BTX-B5 in A. stutchburyi, and of PbTx-2, PbTx-3 and BTX-B5 in P. canaliculus by this LC-MS/MS method. PMID:15284012

  13. 50 CFR 14.21 - Shellfish and fishery products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... propagation, at any Customs port. (b) Pearls. Except for wildlife requiring a permit pursuant to part 17 or 23 of this subchapter, pearls imported or exported for commercial purposes may enter or exit the United... and fishery products will include pearls....

  14. 50 CFR 14.21 - Shellfish and fishery products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... propagation, at any Customs port. (b) Pearls. Except for wildlife requiring a permit pursuant to part 17 or 23 of this subchapter, pearls imported or exported for commercial purposes may enter or exit the United... and fishery products will include pearls....

  15. Overview of zoonotic infections from fish and shellfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zoonosis refers to diseases that can be transferred from animals, whether wild or domesticated, to humans. Zoonotic infections can be divided into: 1) topically acquired infection caused by contact with aquatic animals or their products and 2) food borne infection caused by eating raw or undercooked...

  16. Archaeological shellfish size and later human evolution in Africa

    PubMed Central

    Klein, Richard G.; Steele, Teresa E.

    2013-01-01

    Approximately 50 ka, one or more subgroups of modern humans expanded from Africa to populate the rest of the world. Significant behavioral change accompanied this expansion, and archaeologists commonly seek its roots in the African Middle Stone Age (MSA; ∼200 to ∼50 ka). Easily recognizable art objects and “jewelry” become common only in sites that postdate the MSA in Africa and Eurasia, but some MSA sites contain possible precursors, especially including abstractly incised fragments of ocher and perforated shells interpreted as beads. These proposed art objects have convinced most specialists that MSA people were behaviorally (cognitively) modern, and many argue that population growth explains the appearance of art in the MSA and its post-MSA florescence. The average size of rocky intertidal gastropod species in MSA and later coastal middens allows a test of this idea, because smaller size implies more intense collection, and more intense collection is most readily attributed to growth in the number of human collectors. Here we demonstrate that economically important Cape turban shells and limpets from MSA layers along the south and west coasts of South Africa are consistently and significantly larger than turban shells and limpets in succeeding Later Stone Age (LSA) layers that formed under equivalent environmental conditions. We conclude that whatever cognitive capacity precocious MSA artifacts imply, it was not associated with human population growth. MSA populations remained consistently small by LSA standards, and a substantial increase in population size is obvious only near the MSA/LSA transition, when it is dramatically reflected in the Out-of-Africa expansion. PMID:23776248

  17. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are... may be taken or possessed. (6) Bering Sea Area. (i) In that portion of the area north of the...

  18. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  19. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  20. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  1. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  2. Genomic resource development for shellfish of conservation concern.

    PubMed

    Timmins-Schiffman, Emma B; Friedman, Carolyn S; Metzger, Dave C; White, Samuel J; Roberts, Steven B

    2013-03-01

    Effective conservation of threatened species depends on the ability to assess organism physiology and population demography. To develop genomic resources to better understand the dynamics of two ecologically vulnerable species in the Pacific Northwest of the United States, larval transcriptomes were sequenced for the pinto abalone, Haliotis kamtschatkana kamtschatkana, and the Olympia oyster, Ostrea lurida. Based on comparative species analysis the Ostrea lurida transcriptome (41 136 contigs) is relatively complete. These transcriptomes represent the first significant contribution to genomic resources for both species. Genes are described based on biological function with particular attention to those associated with temperature change, oxidative stress and immune function. In addition, transcriptome-derived genetic markers are provided. Together, these resources provide valuable tools for future studies aimed at conservation of Haliotis kamtschatkana kamtschatkana, Ostrea lurida and related species. PMID:23280275

  3. Water quality and shellfish sanitation. [Patuxent and Choptank River watersheds

    NASA Technical Reports Server (NTRS)

    Eisenberg, M.

    1978-01-01

    The use of remote sensing techniques for collecting bacteriological, physical, and chemical water quality data, locating point and nonpoint sources of pollution, and developing hydrological data was found to be valuable to the Maryland program if it could be produced effectively and rapidly with a minimum amount of ground corroboration.

  4. Committed effective dose from naturally occuring radionuclides in shellfish

    NASA Astrophysics Data System (ADS)

    Khandaker, Mayeen Uddin; Wahib, Norfadira Binti; Amin, Yusoff Mohd.; Bradley, D. A.

    2013-07-01

    Recognizing their importance in the average Malaysian daily diet, the radioactivity concentrations in mollusc- and crustacean-based food have been determined for key naturally occuring radionuclides. Fresh samples collected from various maritime locations around peninsular Malaysia have been processed using standard procedures; the radionuclide concentrations being determined using an HPGe γ-ray spectrometer. For molluscs, assuming secular equilibrium, the range of activities of 238U (226Ra), 232Th (228Ra) and 40K were found to be 3.28±0.35 to 5.34±0.52, 1.20±0.21 to 2.44±0.21 and 118±6 to 281±14 Bq kg-1 dry weight, respectively. The respective values for crustaceans were 3.02±0.57 to 4.70±0.52, 1.38±0.21 to 2.40±0.35 and 216±11 to 316±15 Bq kg-1. The estimated average daily intake of radioactivity from consumption of molluscs are 0.37 Bq kg-1 for 238U (226Ra), 0.16 Bq kg-1 for 232Th (228Ra) and 18 Bq kg-1 for 40K; the respective daily intake values from crustaceans are 0.36 Bq kg-1, 0.16 Bq kg-1 and 23 Bq kg-1. Associated annual committed effective doses from molluscs are estimated to be in the range 21.3 to 34.7 μSv for 226Ra, 19.3 to 39.1 μSv for 228Ra and 17.0 to 40.4 μSv for 40K. For crustaceans, the respective dose ranges are 19.6 to 30.5 μSv, 22.0 to 38.4 μSv and 31.1 to 45.5 μSv, being some several times world average values.

  5. Tracking responses to the 2010 Deepwater Horizon oil spill using trace elements in molluscan shells and tissues

    NASA Astrophysics Data System (ADS)

    Roopnarine, P. D.; Anderson, L.; Roopnarine, D.; Gillikin, D. P.; Goodwin, D.

    2010-12-01

    Documenting the effects of modern stressors on coastal benthic marine communities requires a combination of baseline historical data and modern dynamic data. E.g., landfall of hydrocarbons from the 2010 Deepwater Horizon rig and well explosion in the Gulf of Mexico is impacting coastal areas long affected by natural seepage, as well as petroleum exploration and development. In Louisiana, exploration in coastal areas that began in the 1920s expanded greatly with the development of the first mobile drilling barge in 1933. In total nearly 50,000 wells have been drilled in the Gulf of Mexico since the 1930s. Given this historical context, we are assessing pathways and rates at which crude oil components from the 2010 spill are incorporated into northern Gulf of Mexico coastal food webs. Sclerochronological techniques are being used to unlock the high-resolution physical and chemical records preserved within mollusc shells. We are analyzing historical specimens collected from the late 19th through late 20th centuries, baseline specimens collected in May 2010 in Louisiana and Alabama before visible hydrocarbons were present, and specimens collected in August 2010 after hydrocarbons made landfall. We are examining changes in life history traits (growth rate, recruitment, mortality, reproduction) of the commercial oyster Crassostrea virginica, and other common, co-occurring molluscs that are primary and secondary consumers in Gulf of Mexico coastal food webs. The taxa include the marsh-dwelling gastropod Littoraria irrorata and mussel Geukensia demissa, and open-water species including the bivalves Ischadium recurvum and Tellina alternata. These consumers range from epifaunal, sessile, filter feeders; to infaunal, mobile, deposit feeders; to epifaunal, mobile, omnivorous grazers. In this way, multiple potential pathways into coastal food webs are being monitored. Because environmental perturbations of many scales are recorded by the accretionary growth of mollusc shells

  6. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requests are received and/or are based on priorities as determined by 50 CFR 100.17 and 36 CFR 242.17... (Chionoecetes spp.), and Dungeness crab (Cancer magister). Cub bear means a brown or grizzly bear in its...

  7. 50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... couesi, all species of tanner or snow crab (Chionoecetes spp.), and Dungeness crab (Cancer magister)....

  8. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... crab (Chionoecetes spp.), and Dungeness crab (Cancer magister). Cub bear means a brown or grizzly...

  9. Inactivation of HAV and norovirus surrogates within raw shellfish and other foods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High pressure processing can inactivate hepatitis A virus, (HAV) and the human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), in foods such as oysters, strawberries, and green onions. A 5-min 400-Megapascals (MPa) treatment at 5 degrees C and a 1–min 400-MPa treatment at ...

  10. 50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... age as determined by horn growth annuli. Furbearer means a beaver, coyote, arctic fox, red fox, lynx... hide of a wolf, wolverine, coyote, fox, lynx, marten, mink, weasel, or otter; (ii) The hide and...

  11. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... annuli. Furbearer means a beaver, coyote, arctic fox, red fox, lynx, marten, mink, weasel, muskrat, river... must salvage the following parts for human use: (i) The hide of a wolf, wolverine, coyote, fox,...

  12. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... annuli. Furbearer means a beaver, coyote, arctic fox, red fox, lynx, marten, mink, weasel, muskrat, river... must salvage the following parts for human use: (i) The hide of a wolf, wolverine, coyote, fox,...

  13. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requests are received and/or are based on priorities as determined by 50 CFR 100.17 and 36 CFR 242.17... at least 8 years of age as determined by horn growth annuli. Furbearer means a beaver, coyote, arctic...) The hide of a wolf, wolverine, coyote, fox, lynx, marten, mink, weasel, or otter; (ii) The hide...

  14. 50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... age as determined by horn growth annuli. Furbearer means a beaver, coyote, arctic fox, red fox, lynx... hide of a wolf, wolverine, coyote, fox, lynx, marten, mink, weasel, or otter; (ii) The hide and...

  15. Failure to detect hepatitis B surface antigen (HBsAg) in certified shellfish from New England.

    PubMed Central

    Koff, R S; Connelly, L J

    1976-01-01

    In this study, hard- and soft-shell clams harvested during a one-year period from state approved (certified) clam beds in Maine, Massachusetts, and Rhode Island were tested for HBsAg by radioimmunoassay. HBsAg could not be detected in clam viscera. The role of bivalve mollusk ingestion in transmission of Hepatitis B remains speculative. PMID:1251953

  16. Rocky Intertidal Zonation Pattern in Antofagasta, Chile: Invasive Species and Shellfish Gathering

    PubMed Central

    Castilla, Juan Carlos; Manríquez, Patricio H.; Delgado, Alejandro; Ortiz, Verónica; Jara, María Elisa; Varas, Manuel

    2014-01-01

    Background Biological invasions affecting rocky intertidal zonation patterns, yield information on species interactions. In the Bay of Antofagasta, northern Chile, the non-indigenous tunicate Pyura praeputialis, originally from Australia, has invaded (in the past century or so) and monopolized a major portion of the mid-intertidal rocky shore, displacing upshore the native mussel Perumytilus purpuratus. In Antofagasta the tunicate is subjected to intensive exploitation. Monitoring protocols show that in the past 10 years Antofagasta's tunicate population has experienced a drastic decline, affecting the intertidal zonation pattern. Methodology/Principal Findings A 12.5 km of coastline, on the southern eastern shore of the Bay of Antofagasta, was studied. Eight sites were systematically (1993–1994) or sporadically (2003–2014) monitored for the seaward-shoreward expansion or reduction of the tunicate Pyura praeputialis, and native mussel and barnacle bands. A notable reduction in the mid-intertidal band of P. praeputialis and a seaward expansion of the mussel, Perumytilus purpuratus, and barnacle bands was observed. We suggest that the major cause for the decline in the tunicate is due to its intensive exploitation by rocky shore Pyura-gathers. The rate of extraction of tunicates by professional Pyura-gathers ranged between 256–740 tunicates hour−1. Between 2009–2014 the density of professional Pyura-gather ranged between 0.5–4.5 km−1 per low tide. Hence, 10 professional Pyura-gathers working 1 h for 10 low tides per month, during 6 months, will remove between 307–888 m2 of tunicates. A drastic decline in tunicate recruitment was observed and several P. praeputialis ecosystems services have been lost. Conclusion and Significance In Antofagasta, the continuous and intensive intertidal gathering of the invasive tunicate Pyura praeputialis, has caused a drastic reduction of its population modifying the zonation pattern. Thereby, native mussel Perumytilus purpuratus has regained its ecological center in the intertidal zone. We recorded a Pyura recruitment failure and loss of ecosystem services. PMID:25338112

  17. California commercial/sport fish and shellfish oil toxicity study. Volume 1. Executive summary. Final report

    SciTech Connect

    Kanter, R.G.; Wingert, R.C.; Vick, W.H.; Sowby, M.L.; Foley, C.J.

    1983-12-01

    The effect of oil on three species of California marine organisms, California Halibut (Paralichthys californicus), Northern Anchovy (Engraulis mordax), and California Mussel (Mytilus californianus) were investigated. Adult, larval, and egg life stages of each species were exposed to the water soluble fraction (WSF) of Santa Barbara crude oil in flow-through experiments lasting through the life stage or as long as 120 days. Embryos of all species accumulated hydrocarbons and showed reduced survival with increasing test concentration. Larval halibut demonstrated bent notochords in high test concentration, reduced growth rate in all concentrations, and gill damage in adults in high concentration. Anchovy larvae and adults showed patterns similar to halibut with reduction in growth and head and jaw abnormalities.

  18. 75 FR 28858 - Agency Information Collection (Purchase of Shellfish) Activities Under OMB Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-24

    ... Office of Acquisition and Materiel Management, Department of Veterans Affairs, will submit the collection of information abstracted below to the Office of Management and ] Budget (OMB) for review and comment..., Enterprise Records Service (005R1B), Department of Veterans Affairs, 810 Vermont Avenue, NW., Washington,...

  19. 78 FR 42820 - Agency Information Collection (Purchase of Shellfish) Activities Under OMB Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... Office of Acquisition and Materiel Management, Department of Veterans Affairs, will submit the collection of information abstracted below to the Office of Management and Budget (OMB) for review and comment..., Enterprise Records Service (005R1B), Department of Veterans Affairs, 810 Vermont Avenue NW., Washington,...

  20. EDUCATION WORKSHOP FOR THE FLORIDA MEDICAL COMMUNITY ON THE RISKS ASSOCIATED WITH SHELLFISH CONSUMPTION

    EPA Science Inventory

    People whose immune systems are compromised by liver disease, chemotherapy, etc. are at a substantial risk of contracting a fatal infection from the marine bacteria, Vibrio vulnificus to which they could potentially be exposed by eating raw oysters. It has proven difficult to ge...

  1. Prevalence and Genetic Diversity of Human Sapoviruses in Shellfish from Commercial Production Areas in Galicia, Spain

    PubMed Central

    Varela, Miguel F.; Polo, David

    2015-01-01

    The prevalence of human forms of Sapovirus, an emerging pathogen of human gastroenteritis, was investigated in an 18-month survey from class B mollusc-harvesting areas in two Galician rias (northwest Spain). The detection and quantification of Sapovirus was performed by reverse transcription-real-time PCR, according to the recently developed standard method ISO/TS 15216-1:2013, and genotyping by reverse transcription-nested PCR. The bivalve species studied were wild and cultured mussels (Mytilus galloprovincialis), clams (Venerupis philippinarum and Venerupis decussata), and cockles (Cerastoderma edule). Sapovirus was detected in 30 out of 168 samples (17.9%), with cockles being the species with the highest prevalence of positives (28.1%), followed by clams (22.6%), wild mussels (14.3%), and cultured mussels (12.9%). The estuary in the south of the region demonstrated a higher percentage of positive samples (21.8%) than the one in the north (14.4%). Viral contamination levels for the positive samples ranged between 1.9 × 103 and 1.4 × 105 RNA copies/g of digestive tissue. Thirteen Sapovirus sequences could be obtained based on partial capsid gene sequence and were classified into four genotypes: GI.1 (2 samples), GI.2 (8 samples), GIV.1 (2 samples), and GV.1 (1 sample). PMID:26655761

  2. Overfishing and the replacement of demersal finfish by shellfish: an example from the English Channel.

    PubMed

    Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M

    2014-01-01

    The worldwide depletion of major fish stocks through intensive industrial fishing is thought to have profoundly altered the trophic structure of marine ecosystems. Here we assess changes in the trophic structure of the English Channel marine ecosystem using a 90-year time-series (1920-2010) of commercial fishery landings. Our analysis was based on estimates of the mean trophic level (mTL) of annual landings and the Fishing-in-Balance index (FiB). Food webs of the Channel ecosystem have been altered, as shown by a significant decline in the mTL of fishery landings whilst increases in the FiB index suggest increased fishing effort and fishery expansion. Large, high trophic level species (e.g. spurdog, cod, ling) have been increasingly replaced by smaller, low trophic level fish (e.g. small spotted catsharks) and invertebrates (e.g. scallops, crabs and lobster). Declining trophic levels in fisheries catches have occurred worldwide, with fish catches progressively being replaced by invertebrates. We argue that a network of fisheries closures would help rebalance the trophic status of the Channel and allow regeneration of marine ecosystems. PMID:25010196

  3. Assessment of health risk from heavy metal contamination of shellfish from the Persian Gulf.

    PubMed

    Raissy, Mehdi

    2016-01-01

    The present study assessed the risk of consumption of shrimp and lobster contaminated with mercury, arsenic, cadmium, and lead from the Persian Gulf. The concentrations of mercury, arsenic, lead, and cadmium in shrimp was 62.5, 178.2, 325.2, and 193.5 μg kg(-1) and in lobsters was 53.2, 103.9, 640.6, and 163.1 μg kg(-1), respectively. The maximum daily consumption of shrimp and lobster was calculated to estimate health risks associated with their consumption. The results showed that the maximum allowable consumption of shrimp and lobster was 18-140 g/day for mercury, 33-214 g/day for arsenic, 59-454 g/day for cadmium, and 72-916 g/day for lead. The concentration of metals was within recommended limits for human consumption with the exception of lead, which was found to be above acceptable levels and represents a health risk. PMID:26703978

  4. CONTAMINANT CONCENTRATIONS IN WHOLE-BODY FISH AND SHELLFISH FROM U.S. ESTUARIES

    EPA Science Inventory

    Persistent bioaccumulative and toxic (PBT) pollutants are chemical contaminants that pose risks to ecosystems and human health. For these reasons, available tissue contaminant data from the US EPA Environmental Monitoring and Assessment Program's National Coastal Assessment were...

  5. 50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... ram; the tip of which has grown through 360 degrees of a circle described by the outer surface of the... a male Dall sheep, the tip of which has grown through seven-eighths (315 degrees) of a...

  6. 50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... by 50 CFR 100.17 and 36 CFR 242.17. Regulatory year means July 1-June 30, except for fish and... ram; the tip of which has grown through 360 degrees of a circle described by the outer surface of the... a male Dall sheep, the tip of which has grown through seven-eighths (315 degrees) of a...

  7. Factors preventing the recovery of a historically overexploited shellfish species, Ostrea conchaphila

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The native oyster in estuaries along the Pacific coast of North America, Ostrea conchaphila (prev. Ostrea lurida, Olympia oyster), experienced overexploitation throughout its range in the late 1800’s, resulting in commercial extinction before 1930. Significant harvest restrictions and marine reserv...

  8. Genetic Diversity of Rotavirus Strains Circulating in Environmental Water and Bivalve Shellfish in Thailand

    PubMed Central

    Kittigul, Leera; Panjangampatthana, Apinya; Rupprom, Kitwadee; Pombubpa, Kannika

    2014-01-01

    Rotavirus is a common cause of acute diarrhea in young children worldwide. This study investigated the prevalence and molecular characterization of rotavirus in environmental water and oyster samples in Thailand. A total of 114 water samples and 110 oyster samples were collected and tested for group A rotavirus using RT-nested PCR. Rotavirus genotype was identified by phylogenetic analysis of the VP7 genetic sequences. Group A rotavirus was detected in 21 water samples (18.4%) and six oyster samples (5.4%). Twenty five rotavirus strains were successfully sequenced and classified into four genotypes; G1, G2, G3, and G9. Rotavirus G1 (three strains), G2 (three strains), and G9 (two strains) demonstrated the genetic sequences similar to human strains (90%–99% nucleotide identity), whereas G3 (17 strains) was closely related to animal strains (84%–98% nucleotide identity). G1 strains belonged to lineages I (sub-lineage c) and II. G2 strains belonged to lineage II. G9 strains belonged to lineages III (sub-lineage b) and IV. G3 strains belonged to lineages I, III (sub-lineage c), and IV with a predominance of lineage I. The present study provides important information on the rotavirus strains circulating in the environment. PMID:24469269

  9. Animal-free paralytic shellfish toxin testing--the Canadian perspective to improved health protection.

    PubMed

    Rourke, Wade A; Murphy, Cory J

    2014-01-01

    The performance characteristics of AOAC Official Method 2011.02 (the PCOX method) as a replacement for the AOAC mouse bioassay procedure have been well defined by validation studies, but these data do not communicate the complete story. The context provided by analyzing 9000 regulatory monitoring samples over 3 years demonstrates not only the reduction in animal use but also the increase in food safety that has been realized using a chemistry-based method. Detection of lower toxin levels provided early warning to enable directed sampling as toxin levels increased. The toxin profile information generated by a chemistry-based method was used to detect potential interferences qualitatively and can be used to assess the impact of changes recommended to monitoring programs. Such changes might include which toxins should be included in an action limit or the toxic equivalence factors used for these toxins. PMID:24830144

  10. PROBING NORWALK-LIKE VIRUS PRESENCE IN SHELLFISH WITH ARTIFICIAL NEURAL NETWORKS. (R829784)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Paralytic shellfish toxin concentration and cell density changes in Pyrodinium bahamense -Noctiluca scintillans feeding experiments.

    PubMed

    Azanza, Rhodora V; Cruz, Lourdes J; Cariño, Flerida A; Blanco, Alelea G; Butardo, Vito M

    2010-05-01

    For the first time the potential of Noctiluca scintillans, a non-toxic mixotrophic dinoflagellate, in bioconverting and/or excreting saxitoxin has been illustrated, thus contributing to the limited knowledge on the aspects of toxin pathways in the food chain/web and predator-prey preferences. Noctiluca growth rate increased with higher Pyrodinium concentration but the ratio of Noctiluca to Pyrodinium should at least be 1:250 cells per mL. Noctiluca fed with Pyrodinium alone was found to decrease in number suggesting that the nutrients from this prey were insufficient. This was confirmed by the improved cell density of Noctiluca upon addition of 0.01% casitone to the Pyrodinium-fed Noctiluca. The alternative prey (Gymnodinium sanguineum) slowed down the grazing impact of Noctiluca on Pyrodinium. Noctiluca depleted Gymnodinium earlier than Pyrodinium showing preference over a prey with less saxitoxin. After the feeding experiments, total saxitoxin levels decreased to 72% in the Noctiluca-Pyrodinium setup whereas no saxitoxin was detected in the Noctiluca culture fed with Pyrodinium and G. sanguineum. It is possible that Gymnodinium can provide some nutrients needed to make Noctiluca more efficient in bioconverting saxitoxin. PMID:19800907

  12. Pierisins and CARP-1: ADP-ribosylation of DNA by ARTCs in butterflies and shellfish.

    PubMed

    Nakano, Tsuyoshi; Takahashi-Nakaguchi, Azusa; Yamamoto, Masafumi; Watanabe, Masahiko

    2015-01-01

    The cabbage butterfly, Pieris rapae, and related species possess a previously unknown ADP-ribosylating toxin, guanine specific ADP-ribosyltransferase. This enzyme toxin, known as pierisin, consists of enzymatic N-terminal domain and receptor-binding C-terminal domain, or typical AB-toxin structure. Pierisin efficiently transfers an ADP-ribosyl moiety to the N(2) position of the guanine base of dsDNA. Receptors for pierisin are suggested to be the neutral glycosphingolipids, globotriaosylceramide (Gb3), and globotetraosylceramide (Gb4). This DNA-modifying toxin exhibits strong cytotoxicity and induces apoptosis in various human cell lines, which can be blocked by Bcl-2. Pierisin also produces detrimental effects on the eggs and larvae of the non-habitual parasitoids. In contrast, a natural parasitoid of the cabbage butterfly, Cotesia glomerata, was resistant to this toxin. The physiological role of pierisin in the butterfly is suggested to be a defense factor against parasitization by wasps. Other type of DNA ADP-ribosyltransferase is present in certain kinds of edible clams. For example, the CARP-1 protein found in Meretrix lamarckii consists of an enzymatic domain without a possible receptor-binding domain. Pierisin and CARP-1 are almost fully non-homologous at the amino acid sequence level, but other ADP-ribosyltransferases homologous to pierisin are present in different biological species such as eubacterium Streptomyces. Possible diverse physiological roles of the DNA ADP-ribosyltransferases are discussed. PMID:25033755

  13. The influence of fly ash and shell-fish on physical property of concrete cement

    NASA Astrophysics Data System (ADS)

    Rauf, Nurlaela; Hasruddin, M.

    2012-06-01

    The waste fly ash and shell fish are added to base material of cement (clinker, gypsum, trash and lime stone), for environmental reason. The ratio fly ash and shell fish was varied respectively 375:125; 250:250; 125:375, in grams weight for 2500 grams of total material. The chemical composition of raw material was determined by using x-rays fluorescence (XRF). Physical properties of sample match with Standar Nasional Indonesia (SNI). The physical properties of the best sample is made from composition of fly ash and shell fish as a substitution material on cement was 10% in weight, with ratio 250:250 in grams weight.

  14. Androgenesis: a review through the study of the selfish shellfish Corbicula spp.

    PubMed Central

    Pigneur, L-M; Hedtke, S M; Etoundi, E; Van Doninck, K

    2012-01-01

    Among the asexual reproductive modes, androgenesis is probably one of the most astonishing and least studied mechanisms. In this ‘paternal monopolization', the maternal nuclear genome fails to participate in zygote development and offspring are paternal nuclear clones. Obligate androgenesis is known in only a few organisms, including multiple species of clam in the genus Corbicula. Corbicula is a good system to review the evolutionary consequences of this ‘all-male asexuality' because the cytological mechanisms of androgenetic reproduction have been described. In Corbicula, sperm are unreduced and, after fertilization, the maternal nuclear chromosomes are extruded as two polar bodies. Hermaphroditic lineages of Corbicula have a worldwide distribution and seem to reproduce through androgenesis, whereas their sexual relatives have restricted ranges. The invasive success of these androgenetic Corbicula lineages may be linked to their asexual mode of reproduction. We review the phenomenon of androgenesis, focusing on evolutionary perspectives, using the genus Corbicula as an exemplar system. PMID:22473310

  15. RESTORATION OF 100 SQUARE MILES OF SHELLFISH HABITAT IN LAKE PONTCHARTRAIN MX974852

    EPA Science Inventory

    The project will document the adverse effects of episodic hypoxia on the biotic integrity of Lake Pontchartrain and provide quantitative data on environmental benefits derived from the restoration of 100 square miles of clam habitat in Lake Pontchartrain. This project will prov...

  16. Contaminant levels in fish and shellfish from the EMAP-Estuaries Louisiana Province

    SciTech Connect

    Benson, W.H.; O`Neal, J.M.; Allgood, J.C.; Summers, J.K.

    1994-12-31

    The Environmental Monitoring and Assessment Program-Estuaries (EMAP-E) is a research program designed to assess the ecological condition of the nation`s near-coastal ecosystems. The program is specifically designed to assess changes in ecological condition over broad biogeographic regions and over long time periods. The authors examined approximately 150 sites in the Gulf of Mexico between Anclote Anchorage, FL and the Rio Grande, TX during the summer of 1993. Species collected for chemical analyses included Atlantic croaker, catfish and shrimp. Results will be presented for contaminant levels in edible flesh analyzed for organochlorine and organophosphate pesticides, PCB congeners, butlytins, and a suite of trace elements.

  17. Harvesting Shellfish: Unit F#2 Grade 4. Project COULD: Career Orientation Utilizing Language Development.

    ERIC Educational Resources Information Center

    Coos County Intermediate Education District, North Bend, OR.

    Project COULD (Career Orientation Utilizing Language Development) was developed as a means of building skills, knowledges, and attitudes on elementary children's previously acquired backgrounds. Children begin to speak the grammar and vocabulary characteristic of the language heard most frequently at home and in the immediate environment. A series…

  18. Bioaccessibility of essential and non-essential metals in commercial shellfish from Western Europe and Asia.

    PubMed

    Amiard, Jean-Claude; Amiard-Triquet, Claude; Charbonnier, Laetitia; Mesnil, Aurélie; Rainbow, Philip S; Wang, Wen-Xiong

    2008-06-01

    Maximum acceptable concentrations of metals in food - based on total concentrations - have been established in many countries. To improve risk assessment, it would be better to take into account bioaccessible concentrations. A total of seven species of molluscs from France, UK and Hong Kong was examined in this study including clams, mussels, oysters, scallops and gastropods. The species which have total metal concentrations higher than the most severe food security limits are mainly oysters (all of the three studied species), the gastropod Buccinum undatum for cadmium and zinc, and scallops for cadmium. The lowest bioaccessibility (in % extractability with gut juices) was observed for silver (median for all of the species: 14%), it was moderate for lead (median: 33%) and higher for cadmium, zinc and copper (medians were respectively 54%, 65%, and 70%). In most cases, bioaccessible concentrations remained higher than the safety limits, except for cadmium in scallops and zinc in B. undatum. The influence of feeding habit (masticated or swallowed, addition of vinegar or lemon) on metal bioaccessibility in oysters is limited. On the contrary, cooking the gastropods decreased the bioaccessibility of metals, except silver. PMID:18329777

  19. Solar pond seawater heating system for shellfish mariculture. Final progress report

    SciTech Connect

    Kassner, J.

    1984-01-01

    To supplement natural hard clam (Mercenaria mercenaria) production, Brookhaven Township constructed an onland facility to culture seed clasm in 1980. The facility is only operated from June to October when water temperatures are above 60/sup 0/F, the minimum acceptable for hard clam growth. If seawater could be heated economically, operation of the facility could begin in March, thereby increasing hard clam production. The use of solar energy is particularly suited for this purpose since the seawater need only be warmed a few degrees. After considering a number of active and passive type systems, the Town opted for the latter since it would be simpler to build and operate, less expensive, and at the same time would meet the biological requirements of the hard clam. The two basic components of the solar pond, as the system is known, are a reservoir in which the seawater is heated by direct absorption and a transparent cover to minimize heat loss. For an initial production of 1 million .75mm seed clams, two tanks each measuring 10 feet by 20 feet by 3 feet deep were installed beneath a greenhouse type structure. Total cost of the system was less than $23,000.

  20. Overfishing and the Replacement of Demersal Finfish by Shellfish: An Example from the English Channel

    PubMed Central

    Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M.

    2014-01-01

    The worldwide depletion of major fish stocks through intensive industrial fishing is thought to have profoundly altered the trophic structure of marine ecosystems. Here we assess changes in the trophic structure of the English Channel marine ecosystem using a 90-year time-series (1920–2010) of commercial fishery landings. Our analysis was based on estimates of the mean trophic level (mTL) of annual landings and the Fishing-in-Balance index (FiB). Food webs of the Channel ecosystem have been altered, as shown by a significant decline in the mTL of fishery landings whilst increases in the FiB index suggest increased fishing effort and fishery expansion. Large, high trophic level species (e.g. spurdog, cod, ling) have been increasingly replaced by smaller, low trophic level fish (e.g. small spotted catsharks) and invertebrates (e.g. scallops, crabs and lobster). Declining trophic levels in fisheries catches have occurred worldwide, with fish catches progressively being replaced by invertebrates. We argue that a network of fisheries closures would help rebalance the trophic status of the Channel and allow regeneration of marine ecosystems. PMID:25010196

  1. Assessing the role of benthic filter feeders on phytoplankton production in a shellfish farming site: Mont Saint Michel Bay, France

    NASA Astrophysics Data System (ADS)

    Cugier, Philippe; Struski, Caroline; Blanchard, Michel; Mazurié, Joseph; Pouvreau, Stéphane; Olivier, Frédéric; Trigui, Jihane R.; Thiébaut, Eric

    2010-07-01

    The macrobenthic community of Mont Saint Michel Bay (English Channel, France) is mainly dominated by filter feeders, including cultivated species (oysters and mussels). An ecological model of the bay was developed, coupling a 2D hydro-sedimentary model and two biological models for primary production and filter-feeder filtration. The filter-feeder model includes three cultivated species ( Mytilus edulis, Crassostrea gigas and Ostrea edulis), one invasive species ( Crepidula fornicata) and eight wild native species ( Abra alba, Cerastoderma edule, Glycymeris glycymeris, Lanice conchilega, Macoma balthica, Paphia rhomboides, Sabellaria alveolata, andSpisula ovalis). For cultivated and invasive species, the production of biodeposits was computed to assess their role in restimulating primary production. Chlorophyll a concentrations appeared to be strongly controlled by the filter feeders. When the pressure of each benthic compartment on phytoplankton was estimated separately wild species and the invasive slipper limpet C.fornicata were shown to be key elements in the control of primary production. Conversely, the role of cultivated species, particularly oysters, was weaker. Feedback due to the mineralization of biodeposits also appears to be crucial to fully evaluate the role of filter feeders in primary production.

  2. Effect of the industrial canning on the toxicity of mussels contaminated with diarrhetic shellfish poisoning (DSP) toxins.

    PubMed

    Blanco, Juan; Arévalo, Fabiola; Correa, Jorge; Porro, M Corina; Cabado, Ana G; Vieites, Juan M; Moroño, Angeles

    2016-03-15

    The effect of canning in pickled sauce and autoclaving on weight, toxin content, toxin concentration and toxicity of steamed mussels was studied. Weight decreased by 25.5%. Okadaic acid (OA) and DTX2 content of mussel meat decreased by 24.1 and 42.5%, respectively. The estimated toxicity of the mussel remained nearly unchanged (increased by 2.9%). A part of the toxins lost by the mussels was leached to the sauce but the remaining part should have been thermally degraded. DTX2 underwent more degradation than OA and, in both toxins, free forms more than conjugated ones. This process, therefore, cannot be responsible for the large increments of toxicity of processed mussels -relative to the raw ones-sometimes detected by food processing companies. The final product could be monitored in several ways, but analysing the whole can content or the mussel meat once rehydrated seems to be the most equivalents to the raw mussel controls. PMID:26806209

  3. Total and Inorganic Arsenic in Mid-Atlantic Marine Fish and Shellfish and Implications for Fish Advisories

    SciTech Connect

    Greene, Richard; Crecelius, Eric A.

    2006-02-06

    Up to 33.3 metric tons of arsenic trioxide were spilled off the Middle Atlantic coast of the United States in January of 1992 during a shipping accident. Historical fish tissue data for samples collected in the Delaware Inland Bays before and after the spill reveal a prominent spike in total arsenic in summer flounder following the spill and a gradual decline ever since. In 2002, a small study was conducted to determine whether summer flounder migrating into the Delaware Inland Bays from the Continental Shelf in the spring contain higher body burdens of arsenic than summer flounder migrating out of the Inland Bays in the fall. Total arsenic was significantly higher in the incoming fish. Considering that summer flounder overwinter at the spill site, that arsenic trioxide is a dense powder of limited solubility that would tend to incorporate into the sediments, and that summer flounder are demersal fish, we conclude that summer flounder accumulate arsenic offshore and that the likely source of their extra body burden is the spilled arsenic. Speciation of arsenic in the summer flounder, as well as in Atlantic croaker, striped bass, and hard clam reveal low concentrations (0.5 ? 20 ug/kg ww) of toxic inorganic arsenic. DMA was more than an order of magnitude greater in hard clam meats than in the other species tested, a finding attributed to arsenic uptake by phytoplankton and subsequent dietary uptake by the clam. Risk assessment using the inorganic arsenic concentrations was used to conclude that a fish advisory is not warranted.

  4. Arsenic and arsenic species in shellfish and finfish from the western Arabian Gulf and consumer health risk assessment.

    PubMed

    Krishnakumar, Periyadan K; Qurban, Mohammad A; Stiboller, Michael; Nachman, Keeve E; Joydas, Thadickal V; Manikandan, Karuppasamy P; Mushir, Shemsi Ahsan; Francesconi, Kevin A

    2016-10-01

    This study reports the levels of total arsenic and arsenic species in marine biota such as clams (Meretrix meretrix; N=21) and pearl oyster (Pinctada radiata; N=5) collected from nine costal sites in Jan 2014, and cuttlefish (Sepia pharaonis; N=8), shrimp (Penaeus semisulcatus; N=1), and seven commercially important finfish species (N=23) collected during Apr-May 2013 from seven offshore sites in the western Arabian Gulf. Total As and As species such as dimethylarsinic acid (DMA), arsenobetaine (AB), trimethylarsine oxide (TMAO), arsenocholine (AC), tetramethylarsonium ion (Tetra), arsenosugar-glycerol (As-Gly) and inorganic As (iAs) were determined by using ICPMS and HPLC/ICPMS. In bivalves, the total As concentrations ranged from 16 to 118mg/kg dry mass; the toxic iAs fraction contributed on average less than 0.8% of the total As, while the nontoxic AB fraction formed around 58%. Total As concentrations for the remaining seafood (cuttlefish, shrimp and finfish) ranged from 11 to 134mg/kg dry mass and the iAs and AB fractions contributed on average 0.03% and 81% respectively of the total As. There was no significant relationship between the tissue concentrations of total As and iAs in the samples. There was also no significant relationship between As levels in seafood and geographical location or salinity of the waters from which samples were collected. Based on our results, we recommend introducing a maximum permissible level of arsenic in seafood from the Gulf based on iAs content rather than based on total As. Our analyses of cancer risks and non-cancer hazards identified non-negligible risks and the potential for hazards; the greatest risks were identified for expatriate consumers of bivalves and high-end consumers of seafood. Despite this, many uncertainties remain that would be best addressed by further analyses. PMID:27277209

  5. Comparative Analysis of Lipid Content and Fatty Acid Composition of Commercially Important Fish and Shellfish from Sri Lanka and Japan.

    PubMed

    Devadason, Chandravathany; Jayasinghe, Chamila; Sivakanesan, Ramiah; Senarath, Samanthika; Beppu, Fumiaki; Gotoh, Naohiro

    2016-01-01

    Sri Lanka is surrounded by the Indian Ocean, allowing plenty of fishes to be caught. Moreover, these fishes represent one of the undocumented fish resources in the world and their detailed lipid profiles have not been previously examined. In this study, the lipid content and fatty acid composition of 50 commercially important fishes from the Indian Ocean (Sri Lanka) and the Pacific Ocean (Japan) were compared. The total lipid content and fatty acid composition, including eicosapentaenoic acid (C20:5n-3, EPA) and docosahexaenoic acid (C22:6n-3, DHA), differed significantly among species. Fish from the Pacific Ocean had higher proportions of fatty acids, including EPA and DHA. Herrings and mackerels from both oceanic areas demonstrated high levels of EPA and DHA, and n-3/n-6 ratio. Brackish and freshwater fishes from both groups showed low levels of PUFAs. Fish from the Indian Ocean were high in n-6 fatty acids. Monounsaturated fatty acid levels were high in omnivorous fish from the Pacific Ocean, and saturated fatty acid levels were high in fish from the Indian Ocean. The results of this study will be of value in determining the dietary usefulness of fish caught in Sri Lanka. PMID:27373421

  6. Recruitment dynamics of two ecosystem engineers could drive shellfish populations in U.S. west coast estuaries

    EPA Science Inventory

    Two species of burrowing shrimp, Neotrypaea californiensis and Upogebia pugettensis are important members of intertidal mudflat communities in US West coast estuaries. Both species act as ecosystem engineers and influence the presence of other structured habitats and suspension ...

  7. Modeling of Escherichia coli fluxes on a catchment and the impact on coastal water and shellfish quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We coupled the Soil and Water Assessment Tool (SWAT) with a hydrodynamic model in the Daoulas’ catchment and estuary to estimate daily variations in Escherichia coli fluxes due to catchment activities (manure spreading and wastewater treatment plants discharge) and to assess their impact on coastal ...

  8. CONSOLIDATION OF BASELINE INFORMATION, DEVELOPMENT OF METHODOLOGY, AND INVESTIGATION OF THERMAL IMPACTS ON FRESHWATER SHELLFISH, INSECTS, AND OTHER BIOTA

    EPA Science Inventory

    A computerized information system was developed for storing, retrieving, and analyzing data collected during limnological surveys. To facilitate storage of information, a series of hierarchial codes was developed. These codes not only reduced storage requirements, but also helped...

  9. Modelling shellfish growth with dynamic energy budget models: an application for cockles and mussels in the Oosterschelde (southwest Netherlands).

    PubMed

    Troost, T A; Wijsman, J W M; Saraiva, S; Freitas, V

    2010-11-12

    Dynamic energy budget models for growth of individual cockles (Cerastoderma edule) and mussels (Mytilus edulis) are adjusted and calibrated to the Oosterschelde by formulating and parametrizing their functional responses using an extensive set of field observations. The resulting model predictions fit the observations satisfactorily. Results indicate that food quality and the importance of detritus as a food source are site-specific as well as species-specific. Despite these differences in their calibrated parameter values, both species show a very similar functional response. Compared with other systems, however, the functional responses of mussels in the present study are clearly higher than those of mussels in other systems. This may be explained by the absence of intra-specific competition in the measurement set-up that was used, and therefore supports the idea that the generally small functional response of M. edulis is caused by intra-specific competition. PMID:20921054

  10. ARTIFICIAL NEURAL NETWORKS DETECTION OF VIRAL PRESENCE IN SHELLFISH: RESULTS OF A MULTI-COUNTRY COLLABORATION. (R829784)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada).

    PubMed

    Filgueira, Ramón; Guyondet, Thomas; Bacher, Cédric; Comeau, Luc A

    2015-11-15

    A moratorium on further bivalve leasing was established in 1999-2000 in Prince Edward Island (Canada). Recently, a marine spatial planning process was initiated explore potential mussel culture expansion in Malpeque Bay. This study focuses on the effects of a projected expansion scenario on productivity of existing leases and available suspended food resources. The aim is to provide a robust scientific assessment using available datasets and three modelling approaches ranging in complexity: (1) a connectivity analysis among culture areas; (2) a scenario analysis of organic seston dynamics based on a simplified biogeochemical model; and (3) a scenario analysis of phytoplankton dynamics based on an ecosystem model. These complementary approaches suggest (1) new leases can affect existing culture both through direct connectivity and through bay-scale effects driven by the overall increase in mussel biomass, and (2) a net reduction of phytoplankton within the bounds of its natural variation in the area. PMID:26371845

  12. Modelling shellfish growth with dynamic energy budget models: an application for cockles and mussels in the Oosterschelde (southwest Netherlands)

    PubMed Central

    Troost, T. A.; Wijsman, J. W. M.; Saraiva, S.; Freitas, V.

    2010-01-01

    Dynamic energy budget models for growth of individual cockles (Cerastoderma edule) and mussels (Mytilus edulis) are adjusted and calibrated to the Oosterschelde by formulating and parametrizing their functional responses using an extensive set of field observations. The resulting model predictions fit the observations satisfactorily. Results indicate that food quality and the importance of detritus as a food source are site-specific as well as species-specific. Despite these differences in their calibrated parameter values, both species show a very similar functional response. Compared with other systems, however, the functional responses of mussels in the present study are clearly higher than those of mussels in other systems. This may be explained by the absence of intra-specific competition in the measurement set-up that was used, and therefore supports the idea that the generally small functional response of M. edulis is caused by intra-specific competition. PMID:20921054

  13. Assessing Nation-wide Distributions of Contaminant Levels in Selected Finfish and Shellfish from the Estuaries of the United States

    EPA Science Inventory

    The toxicity of mercury is well documented and has led to laws and regulations governing its use and disposal; however mercury contamination of coastal and estuarine biota continues to be of public concern. The U.S. EPA Environmental Monitoring and Assessment Program provided da...

  14. 75 FR 18549 - In the Matter of Certain Non-Shellfish Derived Glucosamine and Products Containing Same; Notice...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ..., 2009. 74 FR 9428 (March 4, 2009). The complaint alleged violations of section 337 of the Tariff Act of... Investigation as to Respondent Ethical Naturals, Inc. From the Investigation Based Upon a Settlement Agreement... Ethical Naturals, Inc. from the investigation based upon a settlement agreement. The investigation...

  15. Shellfish mariculture facility which employs passive solar heating and heat pump systems. Performance and cost analysis study. Final report

    SciTech Connect

    Zoto, G.A.; Krabach, M.H.

    1984-06-01

    This report incorporates operations data such as clam growth rates, clam biomass buildup, water volume, and algal food requirements compiled while developing a year-round production schedule for production of hard clam seed. The facility includes a passive solar hatchery and heat pump. Three major areas which affect development of energy-efficient mariculture are addressed: biological operation parameters, energy requirements, and system economics. (LEW)

  16. Bacteria associated with false-positive most-probable-number coliform test results for shellfish and estuaries.

    PubMed Central

    Hussong, D; Damaré, J M; Weiner, R M; Colwell, R R

    1981-01-01

    Aerobic and facultatively anaerobic bacteria isolated from false-positive, presumptive, total coliform, most-probable-number tests of Chesapeake Bay oyster, water, and sediment samples were characterized and then classified by numerical taxonomy. A total of 538 bacterial strains clustered into 17 phena, the predominant groups of which were Enterobacteriaceae (including Escherichia coli), Aeromonas spp., and Bacillus spp. Bacillus spp. were recovered most frequently from sediment samples. Gas-producing strains which were not members of the Enterobacteriaceae were not isolated during this study. However, disproportionately large numbers of atypical and anaerogenic lactose-fermenting strains were encountered. We concluded that no single, specific bacterial group can be identified as being responsible for the false-positive reaction in the presumptive coliform test. Instead, the false-positive reaction is a result of complex interactions among various genera, representing predominantly bacteria other than coliforms. PMID:7013700

  17. Rate of occurrence of false-positive results from total coliform most-probable-number analysis of shellfish and estuaries.

    PubMed Central

    Hussong, D; Colwell, R R; Weiner, R M

    1980-01-01

    The incidence of confirmed test, false-positive coliform most-probable-number results was compared with environmental parameters and was found to be inversely related to water temperature. It is concluded that the completed coliform test must be done when water temperatures drop below 15 degrees C. PMID:7004355

  18. Cultivation of the benthic microalga Prorocentrum lima for the production of diarrhetic shellfish poisoning toxins in a vertical flat photobioreactor.

    PubMed

    Wang, Shuai; Chen, Junhui; Li, Zhaoyong; Wang, Yanlong; Fu, Boqiang; Han, Xiaotian; Zheng, Li

    2015-03-01

    In this study, the cultivation conditions of Prorocentrum lima, including temperature, nutrient concentration, photoperiod, and salinity were observed, and then an effective method for the large-volume cultivation of P. lima using a vertical flat photobioreactor was developed for the first time. The maximum cell concentrations and toxin contents of P. lima cultured in the photobioreactor were reached after a 35 days cultivation. Moreover, a step-wise double-sedimentation centrifugation method was used to harvest the microalgae cells, with the harvest rate of 89%. Toxin analysis of dry microalgal powder indicated that OA and DTX1 contents were 15.2 and 21.6 mg g(-1), respectively. These results verify that the culture method using the proposed photobioreactor is effective to massively produce DSP toxin-containing P. lima. This study may serve as a guide for the large-scale production of toxin-producing red-tide benthic microalgae. PMID:25545093

  19. 46 CFR 221.3 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation or..., or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation. (g)...

  20. 46 CFR 221.3 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation or..., or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation. (g)...

  1. 46 CFR 221.3 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation or..., or harvesting of fish, shellfish, marine animals, pearls, shells, or marine vegetation. (g)...

  2. 7 CFR 60.128 - United States country of origin.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... FOR FISH AND SHELLFISH General Provisions Definitions § 60.128 United States country of origin. United States country of origin means in the case of: (a)-(b) (c) Farm-raised Fish and Shellfish: From fish or.... (d) Wild-fish and Shellfish: From fish or shellfish harvested in the waters of the United States...

  3. 7 CFR 60.128 - United States country of origin.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... FOR FISH AND SHELLFISH General Provisions Definitions § 60.128 United States country of origin. United States country of origin means in the case of: (a)-(b) (c) Farm-raised Fish and Shellfish: From fish or.... (d) Wild-fish and Shellfish: From fish or shellfish harvested in the waters of the United States...

  4. 7 CFR 60.128 - United States country of origin.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... FOR FISH AND SHELLFISH General Provisions Definitions § 60.128 United States country of origin. United States country of origin means in the case of: (a)-(b) (c) Farm-raised Fish and Shellfish: From fish or.... (d) Wild-fish and Shellfish: From fish or shellfish harvested in the waters of the United States...

  5. Brevetoxin Depuration in Shellfish via Production of Non-toxic Metabolites: Consequences for Seafood Safety and the Environmental Fate of Biotoxins

    PubMed Central

    Naar, J.; Kubanek, J.; Weidner, A.; Flewelling, L.; Bourdelais, A.; Steidinger, K.; Baden, D. G.

    2010-01-01

    During blooms of the dinoflagellate Karenia brevis, filter-feeders such as oysters and clams bioaccumulate brevetoxins, often to levels that are toxic to humans. In controlled aquarium experiments, we exposed live oysters to bloom levels of toxic K. brevis, followed by 10 weeks of exposure to non-toxic microalgae. Oysters were harvested weekly and analyzed for brevetoxins and brevetoxin metabolites to quantify toxin bioaccumulation and depuration. All of the PbTx-2 concentrated by oysters was immediately converted to a mixture of polar metabolites that were then slowly eliminated from the oysters. However, 90% of measured PbTx-3 was eliminated within two weeks of toxic exposure but without apparent biotransformation. Extracts of oysters containing high levels of PbTx-3 were toxic to mice by intraperitoneal (IP) injection. Extracts of oysters harvested after PbTx-3 had been eliminated were non-toxic despite high concentrations of PbTx-2 metabolites. Oysters collected in Florida during and after a bloom of K. brevis contained polar metabolites of PbTx-2 as well as PbTx-3, but no PbTx-2. Again, PbTx-3 concentration was a good predictor of mouse toxicity. One hundred percent conversion of PbTx-2 to polar metabolites was also accomplished in vitro by spiking oyster or clam homogenate with PbTx-2, followed by a brief incubation at room temperature. These PbTx-2 metabolites did not kill mice, either orally or by intraperitoneal injection, even at concentrations 30 times greater than toxic PbTx-3 levels. PMID:26448967

  6. Bioaccessibility and content of Se in fish and shellfish widely consumed in Mediterranean countries: influence of proteins, fat and heavy metals.

    PubMed

    Marval-León, Jean Rafael; Cámara-Martos, Fernando; Amaro-López, Manuel Angel; Moreno-Rojas, Rafael

    2014-09-01

    Twenty samples of fish and seafood products were selected for determination of total and bioaccessible Se (i.e. soluble and dialyzable). The Se contents ranged between 0.638-0.052 µg/g. The samples of fatty fish such as mackerel and tuna showed higher contents than the species of lean fish, and mainly the fresh water fish, such as salmon, trout and panga showed the lowest contents. The fraction of soluble Se ranged between 43-84% while that the fraction of dialyzable Se did not exceed 14%. No statistically significant correlation was observed between protein content and total and bioaccessible Se content. In contrast, a negative interaction was observed between bioaccessible Se and fat content, and between bioaccessible Se and presence of heavy metals like Cd. PMID:24725145

  7. Run reconstruction and life-history model. Fish/shellfish study number 28. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    SciTech Connect

    Geiger, H.J.; Templin, W.D.; Collie, J.S.; Quinn, T.J.

    1995-08-01

    The Exxon Valdez oil spill resulted in contaminants of juvenile pink salmon (Oncorhynchus gorbuscha) habitat, including freshwater spawning areas in southwestern Prince William Sound (PWS). The authors estimated the loss of returning wild adult pink salmon in 1990-1992, and speculated about this loss in 1993-1994. The primary cause of death was direct poisoning in the embryo stage of development. These studies have low statistical power to detect oil spill effects in the pre- and post- emergent fry and ocean life stages, therefore the true extent of the injury may be understated. The egg-mortality levels increased in the oiled areas in the 1991 and 1992 brood years. The authors also report on a run-reconstruction model, a deterministic model that assumed Markovian transition probabilities for the migration of each individual stock. The authors` most important finding is that of excessive harvest rates on pink salmon stocks in the northern and northwestern part of PWS.

  8. Injury to crabs outside Prince William Sound. Fish/shellfish study number 22. Exxon Valdez oil spill state/federal natural resources damage assessment final report

    SciTech Connect

    Freese, J.L.; O`Clair, C.E.

    1995-09-01

    Commercial Dungeness crab fisheries exist near Kodiak Island and the eastern Alaska Peninsula. Both areas lie within the trajectory of the 1989 Exxon Valdez oil spill. Thirty nine sites in the region were sampled in 1989 and 1990 to assess petroleum hydrocarbon contamination of crab tissues and benthic sediments with which crabs were associated. Female crabs were found in small numbers at 15 sites. Eight of these sites exhibited low levels of petroleum hydrocarbons in the sediments. Only two of the eight sites showed oil contamination that could be linked convincingly to the Exxon Valdez oil spill. None of the crab tissue samples showed evidence of contamination by petroleum hydrocarbons.

  9. Exxon Valdez oil spill. State/federal natural resource damage assessment final report. Database management. Fish/shellfish study number 30

    SciTech Connect

    1993-06-01

    In order to evaluate the extent of damage and injury to natural resources as a result of the Exxon Valdez oil spill, the following types of data would need to be synthesized and carefully managed: (1) historical baseline data to establish conditions prior to the spill; (2) data generated by damage assessment projects to establish damage and extent of injury; and (3) data generated by ongoing monitoring projects to determine the effectiveness of restoration programs. The project was implemented to facilitate access to historical datasets maintained by the Alaska Department of Fish and Game, and to address the need to preserve the raw data generated by selected damage assessment projects associated with the Exxon Valdez oil spill.

  10. Development of microbial and chemical MST tools to identify the origin of the faecal pollution in bathing and shellfish harvesting waters in France.

    PubMed

    Gourmelon, M; Caprais, M P; Mieszkin, S; Marti, R; Wéry, N; Jardé, E; Derrien, M; Jadas-Hécart, A; Communal, P Y; Jaffrezic, A; Pourcher, A M

    2010-09-01

    The microbiological quality of coastal or river waters can be affected by faecal pollution from human or animal sources. An efficient MST (Microbial Source Tracking) toolbox consisting of several host-specific markers would therefore be valuable for identifying the origin of the faecal pollution in the environment and thus for effective resource management and remediation. In this multidisciplinary study, after having tested some MST markers on faecal samples, we compared a selection of 17 parameters corresponding to chemical (steroid ratios, caffeine, and synthetic compounds), bacterial (host-specific Bacteroidales, Lactobacillus amylovorus and Bifidobacterium adolescentis) and viral (genotypes I-IV of F-specific bacteriophages, FRNAPH) markers on environmental water samples (n = 33; wastewater, runoff and river waters) with variable Escherichia coli concentrations. Eleven microbial and chemical parameters were finally chosen for our MST toolbox, based on their specificity for particular pollution sources represented by our samples and their detection in river waters impacted by human or animal pollution; these were: the human-specific chemical compounds caffeine, TCEP (tri(2-chloroethyl)phosphate) and benzophenone; the ratios of sitostanol/coprostanol and coprostanol/(coprostanol+24-ethylcopstanol); real-time PCR (Polymerase Chain Reaction) human-specific (HF183 and B. adolescentis), pig-specific (Pig-2-Bac and L. amylovorus) and ruminant-specific (Rum-2-Bac) markers; and human FRNAPH genogroup II. PMID:20709349

  11. Beta-N-methylamino-L-alanine: LC-MS/MS optimization, screening of cyanobacterial strains and occurrence in shellfish from Thau, a French Mediterranean lagoon.

    PubMed

    Réveillon, Damien; Abadie, Eric; Séchet, Véronique; Brient, Luc; Savar, Véronique; Bardouil, Michèle; Hess, Philipp; Amzil, Zouher

    2014-11-01

    β-N-methylamino-L-alanine (BMAA) is a neurotoxic non-protein amino acid suggested to be involved in neurodegenerative diseases. It was reported to be produced by cyanobacteria, but also found in edible aquatic organisms, thus raising concern of a widespread human exposure. However, the chemical analysis of BMAA and its isomers are controversial, mainly due to the lack of selectivity of the analytical methods. Using factorial design, we have optimized the chromatographic separation of underivatized analogues by a hydrophilic interaction chromatography coupled to tandem mass spectrometry (HILIC-MS/MS) method. A combination of an effective solid phase extraction (SPE) clean-up, appropriate chromatographic resolution and the use of specific mass spectral transitions allowed for the development of a highly selective and sensitive analytical procedure to identify and quantify BMAA and its isomers (in both free and total form) in cyanobacteria and mollusk matrices (LOQ of 0.225 and 0.15 µg/g dry weight, respectively). Ten species of cyanobacteria (six are reported to be BMAA producers) were screened with this method, and neither free nor bound BMAA could be found, while both free and bound DAB were present in almost all samples. Mussels and oysters collected in 2009 in the Thau Lagoon, France, were also screened, and bound BMAA and its two isomers, DAB and AEG, were observed in all samples (from 0.6 to 14.4 µg/g DW), while only several samples contained quantifiable free BMAA. PMID:25405857

  12. Beta-N-methylamino-l-alanine: LC-MS/MS Optimization, Screening of Cyanobacterial Strains and Occurrence in Shellfish from Thau, a French Mediterranean Lagoon

    PubMed Central

    Réveillon, Damien; Abadie, Eric; Séchet, Véronique; Brient, Luc; Savar, Véronique; Bardouil, Michèle; Hess, Philipp; Amzil, Zouher

    2014-01-01

    β-N-methylamino-l-alanine (BMAA) is a neurotoxic non-protein amino acid suggested to be involved in neurodegenerative diseases. It was reported to be produced by cyanobacteria, but also found in edible aquatic organisms, thus raising concern of a widespread human exposure. However, the chemical analysis of BMAA and its isomers are controversial, mainly due to the lack of selectivity of the analytical methods. Using factorial design, we have optimized the chromatographic separation of underivatized analogues by a hydrophilic interaction chromatography coupled to tandem mass spectrometry (HILIC-MS/MS) method. A combination of an effective solid phase extraction (SPE) clean-up, appropriate chromatographic resolution and the use of specific mass spectral transitions allowed for the development of a highly selective and sensitive analytical procedure to identify and quantify BMAA and its isomers (in both free and total form) in cyanobacteria and mollusk matrices (LOQ of 0.225 and 0.15 µg/g dry weight, respectively). Ten species of cyanobacteria (six are reported to be BMAA producers) were screened with this method, and neither free nor bound BMAA could be found, while both free and bound DAB were present in almost all samples. Mussels and oysters collected in 2009 in the Thau Lagoon, France, were also screened, and bound BMAA and its two isomers, DAB and AEG, were observed in all samples (from 0.6 to 14.4 µg/g DW), while only several samples contained quantifiable free BMAA. PMID:25405857

  13. Effect of the industrial steaming on the toxicity, estimated by LC-MS/MS, of mussels exposed for a long time to diarrhetic shellfish poisoning (DSP) toxins.

    PubMed

    Blanco, Juan; Arévalo, Fabiola; Correa, Jorge; Porro, M Corina; Cabado, Ana G; Vieites, Juan M; Moroño, Angeles

    2015-06-15

    The effect of industrial steaming on mussels that had been naturally exposed to DSP toxins for a long time was studied using LC-MS/MS. The estimated toxicity increased with steaming by a percentage that cannot be explained by weight loss. The estimated toxin content per mussel increased substantially with the treatment, which can only be explained by an incorrect estimation by the technique (at the extraction or analytical level) or by the presence of unknown derivatives or analogues. Direct alkaline hydrolysis of the mussel meat yielded more toxin than the standard hydrolysis (hydrolysis of the methanolic extracts), suggesting that extraction was, at least in part, responsible for the increase of toxin content. In situations as the one described in this work, it can be expected that mussels with toxicities well below the regulatory limit could easily surpass that level after industrial steaming, thus producing important losses for food processors. PMID:25660882

  14. Remarkable difference in accumulation of paralytic shellfish poisoning toxins among bivalve species exposed to Pyrodinium bahamense var. compressum bloom in Masinloc Bay, Philippines.

    PubMed

    Montojo, Ulysses M; Sakamoto, Setsuko; Cayme, Mirriam F; Gatdula, Norvida C; Furio, Elsa F; Relox, Juan R; Shigeru Sato; Fukuyo, Yasuwo; Kodama, Masaaki

    2006-07-01

    Seasonal variation of bivalve toxicity was monitored in association with the abundance of the toxic dinoflagellate Pyrodinium bahamense var. compressum in Masinloc Bay, Luzon Island. Among 7 species of bivalve, 6 species became toxic during a bloom of the dinoflagellate. However, remarkable difference in the toxicity was observed among the species. The toxicity of thorny oyster Spondylus squamosus was the highest among the species, showing more than 30 times that of safety consumption level after the peak bloom of the dinoflagellate, while other bivalve species showed much lower toxicity. The toxicity of thorny oyster decreased under absence of the dinoflagellate, but this species maintained a considerably high toxicity throughout a year. Similar trend was observed in penshell Atrina vexillum in a small scale, indicating that these species in the bay are not safe for human consumption almost throughout a year. The toxicity of green mussel Perna viridis increased to significant level during a bloom, but it decreased rapidly when the dinoflagellate disappeared. Toxin analysis of cultured and natural cells showed typical toxin profile of the dinoflagellate. Toxin profile of all the bivalve species reflected the characteristic toxin profile of the dinoflagellate. PMID:16777162

  15. Effect of seawater salinity on pore-size distribution on a poly(styrene)-based HP20 resin and its adsorption of diarrhetic shellfish toxins.

    PubMed

    Fan, Lin; Sun, Geng; Qiu, Jiangbing; Ma, Qimin; Hess, Philipp; Li, Aifeng

    2014-12-19

    In the present study, okadaic acid (OA) and dinophysistoxin-1 (DTX1) were spiked into artificial seawater at low, medium and high estuarine salinities (9‰, 13.5‰ and 27‰). Passive samplers (HP20 resin) used for solid phase adsorption toxin tracking (SPATT) technology were exposed in these seawaters for 12-h periods. Adsorption curves well fitted a pseudo-secondary kinetics model. The highest initial sorption rates of both toxins occurred in the seawater of medium salinity, followed by seawater of low and high estuarine salinity. Pore volumes of micropores (<2 nm) and small mesopores (2 nm

  16. Multiplexed real-time PCR amplification of tlh, tdh and trh genes in Vibrio parahaemolyticus and its rapid detection in shellfish and Gulf of Mexico water.

    PubMed

    Rizvi, Amy V; Bej, Asim K

    2010-10-01

    In this study, we have developed a SYBR Green I-based real-time multiplexed PCR assay for the detection of Vibrio parahaemolyticus in Gulf of Mexico water (gulf water), artificially seeded and natural oysters targeting three hemolysin genes, tlh, tdh and trh in a single reaction. Post-amplification melt-temperature analysis confirmed the amplification of all three targeted genes with high specificity. The detection sensitivity was 10 cfu (initial inoculum) in 1 ml of gulf water or oyster tissue homogenate, following 5 h enrichment. The results showed 58% of the oysters to be positive for tlh, indicating the presence of V. parahaemolyticus; of which 21% were positive for tdh; and 0.7% for trh, signifying the presence of pathogenic strains. The C(t) values showed that oyster tissue matrix had some level of inhibition, whereas the gulf water had negligible effect on PCR amplification. The assay was rapid (approximately 8 h), specific and sensitive, meeting the ISSC guidelines. Rapid detection using real-time multiplexed PCR will help reduce V. parahaemolyticus-related disease outbreaks, thereby increasing consumer confidence and economic success of the seafood industry. PMID:20376562

  17. Facts and Statistics about Food Allergies

    MedlinePlus

    ... Allergens Peanut Tree Nuts Milk Egg Wheat Soy Fish Shellfish Sesame Other Symptoms Diagnosis & Testing Proven Methods ... Allergens Peanut Tree Nuts Milk Egg Wheat Soy Fish Shellfish Sesame Other Symptoms Diagnosis & Testing Proven Methods ...

  18. 27 CFR 4.32a - Voluntary disclosure of major food allergens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... shellfish (for example, crab, lobster, or shrimp), tree nuts (for example, almonds, pecans, or walnuts... shellfish (for example, crab, lobster, or shrimp); and (iii) The names “egg” and “peanuts”, as well as...

  19. 27 CFR 4.32a - Voluntary disclosure of major food allergens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... shellfish (for example, crab, lobster, or shrimp), tree nuts (for example, almonds, pecans, or walnuts... shellfish (for example, crab, lobster, or shrimp); and (iii) The names “egg” and “peanuts”, as well as...

  20. 27 CFR 4.32a - Voluntary disclosure of major food allergens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... shellfish (for example, crab, lobster, or shrimp), tree nuts (for example, almonds, pecans, or walnuts... shellfish (for example, crab, lobster, or shrimp); and (iii) The names “egg” and “peanuts”, as well as...