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1

Seawater and shellfish (Geukensia demissa) quality along the Western Coast of Assateague Island National Seashore, Maryland: an area impacted by feral horses and agricultural runoff.  

PubMed

We evaluated the quality of seawater and ribbed mussels (Gukensia demissa) at six sites along the West Coast of Assateague Island National Seashore (ASIS), a barrier island popular with tourists and fishermen. Parameters evaluated were summertime temperature, pH, salinity, dissolved oxygen, total phosphorus, total ammonia nitrogen, and nitrite levels for seawater and total heterotrophic plate counts and total Vibrionaceae levels for the ribbed mussels. Approximately 150 feral horses (Equus caballus) are located on ASIS and, combined with agricultural runoff from animals and croplands, local wildlife, and anthropogenic inputs, contribute to nutrient loads affecting water and shellfish quality. The average monthly dissolved oxygen for June was 2.65 mg L(-1), below the minimum acceptable threshold of 3.0 mg L(-1). Along Chincoteague Bay, total phosphorus generally exceeded the maximum level of 0.037 mg L(-1), as set by the Maryland Coastal Bays Program management objective for seagrasses, with a high of 1.92 mg L(-1) in June, some 50-fold higher than the recommended threshold. Total ammonia nitrogen approached levels harmful to fish, with a maximum recorded value of 0.093 mg L(-1). Levels of total heterotrophic bacteria spiked to 9.5 x 10(6) cells g(-1) of mussel tissue in August in Sinepuxent Bay, leading to mussels which exceeded acceptable standards for edible bivalves by 19-fold. An average of 76% of the bacterial isolates were in the Vibrionaceae family. Together, these data suggest poor stewardship of our coastal environment and the need for new intervention strategies to reduce chemical and biological contamination of our marine resources. PMID:19132436

Lambert, Mary S; Ozbay, Gulnihal; Richards, Gary P

2009-08-01

2

Population structure of the ribbed mussel Geukensia demissa in salt marshes in the southern Gulf of St. Lawrence, Canada  

Microsoft Academic Search

The ribbed mussel, Geukensia demissa, is highly dependent on the cordgrass Spartina alterniflora for amelioration from environmental stress and substrate stabilization. Spartina alterniflora is a foundation species in marshes, and G. demissa is typically associated with cordgrass beds. Marshes in the southern Gulf of St. Lawrence are experiencing erosion and degradation,\\u000a presumably as a result of increases in sea level,

Cortney Watt; David J. Garbary; Caroline Longtin

2011-01-01

3

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

USGS Publications Warehouse

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.

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

2005-01-01

4

Isolation and identification of an ice-nucleating bacterium from the gills of the intertidal bivalve mollusc Geukensia demissa.  

PubMed

In the fall, freeze tolerant intertidal invertebrates usually produce ice-nucleating proteins that are secreted into the hemolymph. These proteins help protect against freeze damage by insuring that ice formation is limited to extracellular spaces. Geukensia demissa, a freeze tolerant, salt marsh bivalve mollusc was examined for the presence of ice nucleating proteins. The ice-nucleating temperature (INT) of the hemolymph was not significantly different from artificial seawater of the same salinity indicating the lack of an ice nucleating protein in the hemolymph. The palial fluid did have an elevated INT, indicating the presence of an ice nucleator. The INT of the palial fluid was significantly reduced by boiling and filtration through a 0.45-&mgr;m filter. High INT was also observed in the seawater associated with the bivalves, and was demonstrated in water samples collected from salt marshes but not sand and pebble beaches. Moreover, the INT of water samples collected from a salt marsh decreased in the summer. All of these data suggest that the ice-nucleating agents in the hemolymph and the seawater are ice-nucleating bacteria. One species of ice-nucleating bacteria, Pseudomonas fulva was isolated from the gills of Geukensia. These bacteria could perform the same function as hemolymph ice-nucleating proteins by limiting ice formation to extracellular compartments. PMID:11399277

Loomis, S H.; Zinser, M

2001-07-01

5

Particle selection in the ribbed mussel Geukensia demissa and the Eastern oyster Crassostrea virginica: Effect of microalgae growth stage  

NASA Astrophysics Data System (ADS)

We studied particle selection in the ribbed mussel Geukensia demissa, an important suspension-feeding inhabitant of estuaries and intertidal zones of salt marshes along the Atlantic coast of North America. Adult mussels were fed on several mixtures of microalgal cultures (1) in exponential or (2) in stationary phase of growth, and the proportional occurrence of algal species in pseudofeces was examined by flow cytometry. The Eastern oyster, Crassostrea virginica, was chosen as a reference. Results showed that both mussels and oysters were able to selectively ingest or reject our experimental microalgae. Moreover, the pre-ingestive particle selection was affected by microalgal growth phase, particularly in mussels. For instance, the sorting efficiency index increased significantly in mussels fed with a blend made of Nitzschia closterium, Isochrysis sp. and Tetraselmis suesica harvested in stationary growth phase, as compared to the same blend made with microalgae in exponential growth phase. Isochrysis sp. and T. suesica were preferentially ingested by both bivalves whereas N. closterium, was preferentially rejected in pseudofeces. These results demonstrate particle selection in ribbed mussel and underline the effect of algae growth phase on the sorting mechanisms.

Pales Espinosa, Emmanuelle; Allam, Bassem; Ford, Susan E.

2008-08-01

6

Seston available as a food resource for the ribbed mussel ( Geukensia demissa) in a North American, mid-Atlantic saltmarsh  

NASA Astrophysics Data System (ADS)

We studied the composition of the <25 ?m seston size fraction as a food resource potentially available to suspension feeding ribbed mussels, Geukensia demissa, over an annual cycle in Canary Creek saltmarsh, Delaware Bay. There were significant seasonal variations in the concentration of particulate organic carbon (POC), particulate organic nitrogen (PON), and total carbohydrate, but not cellulose. The concentration of cellulose, measured by hydrolytic cellulase enzyme assay, was relatively low (seasonal range 24 to 35 ?g l -1) and only comprised from 3% of total carbohydrate in May 1996 to 13% in November 1995. We used the biomass of microalgae, estimated from chlorophyll a, and abundance of free-living bacteria and heterotrophic nanoflagellates to calculate each component's equivalent carbon content. Microalgae were the most dominant carbon source (62% annually) among the four identified components (phytoplankton, bacteria, heterotrophic nanoflagellates, and cellulose) in all seasons except in August 1995 when carbon from bacteria was most abundant (55%). The annual average carbon equivalents of heterotrophic nanoflagellates and cellulose were relatively small (2 and 4%, respectively). The total concentration of POC in the seston was much greater than the carbon derived from the four identified components. The proportions that these identified components contributed to POC varied seasonally and combined only accounted for 8-24% of POC. Based on these estimates, the bulk of the POC in Canary Creek marsh was not associated with any of the four components we identified. We suggest that this uncharacterized material was some type of non-lignocellulosic, amorphous detritus of unknown utility as a food resource for ribbed mussels.

Huang, S.-C.; Kreeger, D. A.; Newell, R. I. E.

2003-03-01

7

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

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

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

2014-01-01

8

WHERE DOES LECANORA DEMISSA (ASCOMYCOTA, LECANORALES) BELONG?  

Microsoft Academic Search

Abstract:Lecanora demissa (Körb.) Zahlbr. is a crustose, lobate lichen that produces soredia and conidiomata but no apothecia. Its placement in Lecanora has long been questioned but nothing better has been proposed. We have studied the nuclear rDNA of the ITS regions and the SSU of L. demissa. In an alignment of the ITS regions of several representatives of Lecanora s.

Ulf Arup; Martin Grube

1999-01-01

9

Shellfish Biotoxins  

NSDL National Science Digital Library

This Fisheries and Oceans Canada website provides information regarding shellfish biotoxins and shellfish closures in the Pacific region of Canada. Links are provided to information about amnesic shellfish poisoning biotoxins, paralytic shellfish poisoning biotoxins, other shellfish biotoxins, and shellfish contamination closures.

10

Shellfish Toxicity  

NSDL National Science Digital Library

This eMedicine Clinical Knowledge Base webpage features information about shellfish toxicity for physicians and other healthcare professionals. Highlighting the four distinct shellfish poisoning syndromes - Paralytic shellfish poisoning (PSP), Neurologic shellfish poisoning (NSP), Diarrhetic shellfish poisoning (DSP), and Amnesic shellfish poisoning (ASP) this webpage discusses background, pathophysiology, frequency, mortality/morbidity, age, and clinical descriptions. It also takes a deeper look at differentials, laboratory workup, treatment, medication, follow-up, medical/legal pitfalls, special concerns, and a bibliography.

Arnold, Thomas

11

Particle selection in the ribbed mussel Geukensia demissa and the Eastern oyster Crassostrea virginica: Effect of microalgae growth stage  

E-print Network

closterium, Isochrysis sp. and Tetraselmis suesica harvested in stationary growth phase, as compared to the same blend made with microalgae in exponential growth phase. Isochrysis sp. and T. suesica were

Allam, Bassem

12

Shellfish Allergy  

MedlinePLUS

... tuna or cod) and shellfish (like lobster or clams). Even though they both fall into the category ... crustaceans (like shrimp, crab, or lobster) mollusks (like clams, mussels, oysters, or scallops) Some people with shellfish ...

13

Shellfish Allergy  

MedlinePLUS

... Wheat Soy Fish Shellfish Other Symptoms Diagnosis & Testing Proven Methods Skin Prick Tests Blood Tests Oral Food ... Wheat Soy Fish Shellfish Other Symptoms Diagnosis & Testing Proven Methods Skin Prick Tests Blood Tests Oral Food ...

14

Shellfish Allergy  

MedlinePLUS

... tuna or cod) and shellfish (like lobster or clams). Even though they both fall into the category ... like shrimp, crab, or lobster) and mollusks (like clams, mussels, oysters, scallops, octopus, or squid). Some people ...

15

Neurotoxic Shellfish Poisoning  

MedlinePLUS

Neurotoxic Shellfish Poisoning Causative organism: Karenia brevis Toxins produced: Brevetoxins Neurotoxic Shellfish Poisoning (NSP) produces an intoxication syndrome nearly identical to that of ciguatera in which gastrointestinal and ...

16

Amnesic Shellfish Poisoning  

MedlinePLUS

... toxin, domoic acid. Shellfish beds are closed to harvesting when the domoic acid concentration reaches 20 µg/g shellfish meat. However, since fish and crab viscera can also contain domoic acid, ...

17

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...

18

Not all shellfish \\  

Microsoft Academic Search

The popularity of shellfish has been increasing worldwide, with a consequent increase in adverse reactions that can be allergic\\u000a or toxic. The approximate prevalence of shellfish allergy is estimated at 0.5-2.5% of the general population, depending on\\u000a degree of consumption by age and geographic regions. The manifestations of shellfish allergy vary widely, but it tends to\\u000a be more severe than

Chee K Woo; Sami L Bahna

2011-01-01

19

Diarrheic Shellfish Poisoning  

NSDL National Science Digital Library

This web page discusses Diarrheic Shellfish Poisoning (DSP), a gastrointestinal illness caused by the consumption of contaminated shellfish. The associated toxins are okadaic acid and its derivatives, which are produced by the marine dinoflagellate Dinophysis. This page describes clinical presentation (symptoms) of DSP, diagnosis, management and treatment, chemical structure of okadaic acid, molecular mechanism of action, and references.

20

Poisoning - fish and shellfish  

MedlinePLUS

... blooming in the ocean, such as during “"red tide." A red tide occurs when there is a rapid increase in ... poisonings also increases when there is a "red tide." Shellfish poisoning occurs in seafood with two shells ...

21

Red Tide and Shellfish Poisoning  

NSDL National Science Digital Library

This EnviroFacts informational page discusses how red tide develops and how people might be affected by this phenomenon. It covers physical damage, oxygen depletion, direct poisoning, and indirect poisoning including paralytic shellfish poisoning (PSP), diarrhetic shellfish poisoning (DSP), neurotoxic shellfish poisoning (NSP), amnesiac shellfish poisoning (ASP), and aerosol toxins. The page concludes with a discussion of red tide and the role of the sea fisheries research institute.

Maneveldt, Gavin W.

22

DiarrheticShellfishPoisoningtoxins: thestorybehindarecentcaseofhuman  

E-print Network

to Diarrhetic Shellfish Poisoning Diarrhetic Shellfish Poisoning (DSP) can occur following the consumption (3.5 %) individuals reported their illness to the relevant food authority. The mussels were by the Food Standards Agency Scotland for marine biotoxins in shellfish) for Norovirus and biotoxin analyses

23

Paralytic Shellfish Poisoning (PSP)  

NSDL National Science Digital Library

This web page discusses Paralytic Shellfish Poisoning (PSP), a marine toxin disease with both gastrointestinal and neurologic symptoms reported worldwide. It is caused predominantly by the consumption of contaminated shellfish. Gonyaulacoid dinoflagellates are the source of PSP marine toxins. These unicellular dinoflagellates develop algal blooms throughout the world and produce at least 12 toxins which are tetrahydropurines, and heat and acid stable. Saxitoxin was the first characterized and the best understood. This page describes clinical presentation of PSP (including symptoms), diagnosis, management and treatment, the chemical structure of saxitoxin, molecular mechanism of action, and references.

24

Paralytic Shellfish Poisoning  

MedlinePLUS

... sea otters + , sea birds. Squid, zooplankton, and other benthic invertebrates. *Found to contain algal toxins, or to be adversely affected by toxic or harmful marine algae. + Causative algae implicated, not confirmed. Medical Community Paralytic Shellfish Poisoning Additional Information on PSP including: ...

25

Neurotoxic shellfish poisoning.  

PubMed

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

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

2008-01-01

26

Domoic Acid and Amnesiac Shellfish Poisoning  

NSDL National Science Digital Library

This National SeaGrant (PDF) publication discusses Red Tide, Paralytic Shellfish Poisoning (PSP), Domoic Acid, and Amnesiac Shellfish Poisoning (ASP). It includes a description of symptoms as well as a contact number for the shellfish harvest hotline.

SeaGrant; Oregon State University; NOAA

27

NOAA's Science Supports Shellfish Aquaculture  

E-print Network

of the biological effects of ocean acidification on cultured species. NOAA is also restoring native oyster habitat shellfish in Puget Sound. Ocean Acidification Data Benefits West Coast Shellfish Industry Ocean acidification is considered by many to be one of the biggest oceanographic challenges in the coming century

28

MFR PAPER 1300 Shellfish Diseases  

E-print Network

with other forms of food animal production is discussed. The common shellfish diseases are listed. The experimental optimal and lethal concentrations of bacteria for shellfish larvae are defined. An interrelation, and varying degrees of Louis Leibovitz is with the Depart- ment of Avian and Aquatic Animal Medicine, New York

29

Freezing Fish and Shellfish.  

E-print Network

. Allow 1 pound per serving. 3. Dressed- Entrails and scales removed. The head, fins and tail mayor may not be re moved. Allow 1 pound per serving. In-the-round 4. Fillets, chunks and steaks - Fillets with or without the skin on are usually boneless... shellfish. Because fish of a higher fat content are more easily oxidized, their storage life is 1 to 3 months. Fish in this category include tuna, mackerel, mullet and salmon. Remove back (1) Remove legs (2) Remove entrails (3) and wash centl...

Nickelson, Ranzell; Reddell, Annette

1980-01-01

30

November 2012 Washington Shellfish Initiative  

E-print Network

November 2012 Washington Shellfish Initiative Scientific Summary of Ocean Acidification Panel on Ocean Acidification #12;NOTICE from NOAA Mention of a commercial company or product does and Back Cover Graphic: Acknowledgments: Scientific Summary of Ocean Acidification in Washington State

31

Dimorphisms and self-incompatibility in the distylous species Palicourea demissa (Rubiaceae): possible implications for its reproductive output.  

PubMed

Distyly has been interpreted as a mechanism that favors cross-fertilization. In this research we describe floral attributes and ancillary floral polymorphisms typically associated to heterostylous plants in Palicourea demissa (Rubiaceae), a distylous shrub of the Venezuelan Andes cloud forests. A hand-pollination experiment was done to evaluate self- and intramorph incompatibility and female reproductive output in both floral morphs. The studied population was morphologically distylous but morph differences in most ancillary floral polymorphisms and reciprocity of the sexual organ heights were found. The floral morphs were self-incompatible and did not differ in fruit set under controlled cross-pollination conditions, but at the population level they exhibited imperfect reciprocal herkogamy. Fruits and seeds of short-styled plants were larger than those of long-styled plants and fruit set was higher in short-styled plants under natural conditions, suggesting a higher reproductive potential among short-styled plants. Given the 1:1 morph ratio within the studied population, further evidence is needed to determine the influence of floral visitors and seed dispersers in the expression of heterostyly in P. demissa under natural conditions. PMID:20577893

Valois-Cuesta, Hamleth; Soriano, Pascual J; Ornelas, Juan Francisco

2011-01-01

32

Tide pushing shellfishers into red  

NSDL National Science Digital Library

This USA Today article provides very general information about the 2005 red tide outbreak off the Gulf of Maine. It offers possible explanations for the outbreak, what is being done to protect people from hazards related to red tide, and how the outbreak has devastated local shellfishers.

Rick Hampson

33

Risk Assessment of Shellfish Toxins  

PubMed Central

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

Munday, Rex; Reeve, John

2013-01-01

34

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...

35

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...

36

7 CFR 60.133 - Wild fish and shellfish.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Wild fish and shellfish. 60.133 Section 60...CONTINUED) COUNTRY OF ORIGIN LABELING FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and...

2011-01-01

37

7 CFR 60.133 - Wild fish and shellfish.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Wild fish and shellfish. 60.133 Section 60...CONTINUED) COUNTRY OF ORIGIN LABELING FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and...

2013-01-01

38

7 CFR 60.133 - Wild fish and shellfish.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Wild fish and shellfish. 60.133 Section 60...CONTINUED) COUNTRY OF ORIGIN LABELING FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and...

2012-01-01

39

7 CFR 60.133 - Wild fish and shellfish.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Wild fish and shellfish. 60.133 Section 60...CONTINUED) COUNTRY OF ORIGIN LABELING FOR FISH AND SHELLFISH General Provisions Definitions § 60.133 Wild fish and shellfish. Wild fish and...

2014-01-01

40

CONTAMINATION OF ATLANTIC COAST COMMERCIAL SHELLFISH  

Technology Transfer Automated Retrieval System (TEKTRAN)

Shellfish (oysters and/or clams) were obtained from 37 commercial harvesting sites in 12 Atlantic coast states from Maine to Florida and 1 site in New Brunswick, Canada. Gill washings from 25 shellfish at each site were examined by immunofluorescence microscopy (IFA) for oocysts of Cryptosporidium. ...

41

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...

42

Red Tide or Neurotoxic Shellfish Poisoning  

NSDL National Science Digital Library

This web page discusses Red Tide and Neurotoxic Shellfish Poisoning, a milder gastroenteritis with neurologic symptoms compared with Paralytic Shellfish Poisoning. The classic causative organism is the dinoflagellate Gymnodinium breve, which produces neurotoxic toxins known as brevetoxins. This page describes clinical presentation of NSP (including symptoms), diagnosis, management and treatment, molecular mechanism of action, and references.

43

Fish and Shellfish Associated Disease Outbreaks.  

ERIC Educational Resources Information Center

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)

Levin, M.

1978-01-01

44

Mapping shellfish distribution using hyperspectral remote sensing  

NASA Astrophysics Data System (ADS)

A majority of all baseline shellfish maps are currently produced through ground surveys and manual aerial photo interpretation, a tedious process which is time-consuming and prone to human errors. The first objective of this research was to investigate and document the feasibility of using remotely sensed imagery to identify and classify intertidal shellfish resources. A specific task was to spectrally identify the differences between mud and shellfish using a combination of hyperspectral remote sensing data and extensive in situ spectral data. A second objective was the identification of spectrally relevant portions of the electromagnetic spectrum that are useful in identification of shellfish and to determine if there is a statistical difference between mud and shellfish. This research found that it was feasible to accurately identify shellfish and distinguish shellfish from mud. It was found that with the incorporation of in situ derived spectral endmembers, the accuracy of the mapping procedure was lower than deriving spectral endmembers directly from the remotely sensed imagery. It was also noted that changes within the habitat could have occurred between the acquisition of the remotely sensed HyMAP and AISA imagery and the acquisition of the in situ data may have contributed to lower accuracy results. Secondary objective results indicate that the visible and near infra-red portions of the electromagnetic spectrum are the most useful for discriminating between shellfish and mud. While statistical analysis showed there was a significant difference between mud and shellfish, there was also a high degree of statistical differences within the collected shellfish data that a degree of uncertainty remains. The use of remotely sensed imagery, in situ ancillary data and field verification does result in shellfish maps that are less error prone than previous methodologies and allows for the mapping of remote or hard to access areas of shellfish resources. It is hoped that the creation of a repeatable, timely, and cost effective mapping technique that is less prone to error for the creation of baseline shellfish maps will benefit the coastal community at national and international levels.

Vincent, Jeffrey S.

45

Red Tide and Paralytic Shellfish Poisoning  

ERIC Educational Resources Information Center

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)

Dale, Barrie; Yentsch, Clarice M.

1978-01-01

46

Not all shellfish "allergy" is allergy!  

PubMed Central

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

2011-01-01

47

December 2011 http://aquaculture.noaa.gov NOAA's National Shellfish Initiative  

E-print Network

December 2011 http://aquaculture.noaa.gov NOAA's National Shellfish Initiative The goal of the National Shellfish Initiative is to increase shellfish aquaculture for commercial and restoration purposes by shellfish aquaculture and aims to increase shellfish production and wild shellfish populations in U

48

48 CFR 852.270-3 - Purchase of shellfish.  

Code of Federal Regulations, 2010 CFR

...prescribed in 870.111-3, insert the following clause: Purchase of Shellfish (APR 1984) The bidder certifies that oysters, clams, and mussels will be furnished only from plants approved by and operated under the supervision of shellfish...

2010-10-01

49

Shellfish Aquaculture in Delaware's Inland Bays Status, Opportunities, and Constraints  

E-print Network

Shellfish Aquaculture in Delaware's Inland Bays Status, Opportunities, and Constraints Compiled - Shellfish Aquaculture in Delaware's Inland Bays Status, Opportunities, and Constraints TABLE OF CONTENTS....................................................................................................... 5 1. Introduction and Overview of Aquaculture .................................................. 8 2

Firestone, Jeremy

50

48 CFR 852.270-3 - Purchase of shellfish.  

Code of Federal Regulations, 2011 CFR

...prescribed in 870.111-3, insert the following clause: Purchase of Shellfish (APR 1984) The bidder certifies that oysters, clams, and mussels will be furnished only from plants approved by and operated under the supervision of shellfish...

2011-10-01

51

48 CFR 852.270-3 - Purchase of shellfish.  

Code of Federal Regulations, 2012 CFR

...prescribed in 870.111-3, insert the following clause: Purchase of Shellfish (APR 1984) The bidder certifies that oysters, clams, and mussels will be furnished only from plants approved by and operated under the supervision of shellfish...

2012-10-01

52

48 CFR 852.270-3 - Purchase of shellfish.  

Code of Federal Regulations, 2013 CFR

...prescribed in 870.111-3, insert the following clause: Purchase of Shellfish (APR 1984) The bidder certifies that oysters, clams, and mussels will be furnished only from plants approved by and operated under the supervision of shellfish...

2013-10-01

53

48 CFR 852.270-3 - Purchase of shellfish.  

Code of Federal Regulations, 2014 CFR

...prescribed in 870.111-3, insert the following clause: Purchase of Shellfish (APR 1984) The bidder certifies that oysters, clams, and mussels will be furnished only from plants approved by and operated under the supervision of shellfish...

2014-10-01

54

The physics of open-water shellfish aquaculture  

Microsoft Academic Search

Aquaculture of shellfish species is expanding in many countries. Limitations on, and competition for, inshore water space is making offshore shellfish developments more attractive. Here we review issues relating to the design and mechanics of shellfish longline structures in relation to the offshore marine environment. Two main facets are explored: (i) the effect of the flow (waves and currents) on

Craig Stevens; David Plew; Neil Hartstein; David Fredriksson

2008-01-01

55

Surveillance of algal toxins in shellfish from Scottish waters  

Microsoft Academic Search

Shellfish samples were collected from coastal and offshore aquaculture sites and harvesting areas in Scottish waters between March 2003 and September 2004. Samples were analysed for the presence of algal toxins using traditional mouse bioassays for the detection of paralytic shellfish poisoning (PSP) toxins and diarrhetic shellfish poisoning (DSP) toxins; immuno-lateral flow chromatography for the detection of PSP toxins in

L. A. Stobo; J.-P. C. L. Lacaze; A. C. Scott; J. Petrie; E. A. Turrell

2008-01-01

56

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...

57

Paralytic Shellfish Poisoning: A Case Series  

PubMed Central

We describe a case series of seven patients presenting to an emergency department with symptoms of paralytic shellfish poisoning. They developed varying degrees of nausea, vomiting, diarrhea, weakness, ataxia and paresthesias after eating mussels harvested from a beach near their resort. Four patients were admitted to the hospital, one due to increasing respiratory failure requiring endotracheal intubation and the remainder for respiratory monitoring. All patients made a full recovery, most within 24 hours. The ability to recognize and identify paralytic shellfish poisoning and manage its complications are important to providers of emergency medicine. PMID:25035737

Hurley, William; Wolterstorff, Cameron; MacDonald, Ryan; Schultz, Debora

2014-01-01

58

Operational application of a rapid antibody-based detection assay for first line screening of paralytic shellfish toxins in shellfish  

Microsoft Academic Search

Paralytic shellfish poisoning toxins (PSP-toxins) are potent neurotoxins associated with marine dinoflagellates and may accumulate in filter-feeding shellfish to cause food intoxication in human. Monitoring programs for PSP in shellfish rely heavily on the use of traditional mouse bioassay (MBA). Considerable progress has been made in developing a reliable, rapid and relatively convenient assay for mass screening of possible PSP

Chun-Kwan Wong; Patricia Hung; Edward A. L. Ng; Kellie L. H. Lee; Grace T. C. Wong; Kai-Man Kam

2010-01-01

59

BARATARIA/TERREBONNE SHELLFISH CHALLENGE INITATIVE  

EPA Science Inventory

This project provides the resources to the Barataria/Terrebonne National Estuary Program to work toward implementation of projects in the four general categories below that will allow the opening of closed shellfish growing waters to harvest. v Connecting poorly operating se...

60

Harmful Algal Blooms: Neurotoxic Shellfish Poisoning  

NSDL National Science Digital Library

This University of Maryland SeaGrant web page discusses the toxic dinoflagellate Gymnodinium breve and its role in red tide blooms and Neurotoxic Shellfish Poisoning (NSP). The page explores the economic, ecological, and health-related effects of red tide blooms, and the causative accumulation of G. breve into blooms that produce the powerful neurotoxins known as brevetoxins.

Andrew Kane

61

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...

62

Harmful Algal Blooms: Paralytic Shellfish Poisoning  

NSDL National Science Digital Library

This University of Maryland SeaGrant web page explores outbreaks of paralytic shellfish poisoning (PSP), a problem on both the East and West coasts of the US that is caused by several closely related species in the genus Alexandrium. The page explores the underlying physical mechanisms and localization of PSP outbreaks, as well as economic impact.

Andrew Kane

63

Harmful Algal Blooms: Amnesic Shellfish Poisoning  

NSDL National Science Digital Library

This University of Maryland SeaGrant web page discusses amnesic shellfish poisoning (ASP), also known as domoic acid poisoning (DAP). The page discusses the production of domoic acid by the diatom Pseudo-nitzschia, geographic locations of detection, and economic impacts.

Andrew Kane

64

Francisella infections in fish and shellfish.  

PubMed

A series of recent reports have implicated bacteria from the family Francisellaceae as the cause of disease in farmed and wild fish and shellfish species such as Atlantic cod, Gadus morhua L., tilapia, Oreochromis spp., Atlantic salmon, Salmo salar L., three-line grunt, Parapristipoma trilineatum (Thunberg), ornamental cichlid species, hybrid striped bass Morone chrysops x M. saxatilis and, recently, a shellfish species, the giant abalone, Haliotisgigantea Gmelin. The range of taxa affected will very probably rise as it is likely that there has been considerable under-reporting to date of these disease agents. In common with other Francisella species, their isolation and culture require specialized solid and liquid media containing cysteine and a source of iron. This likely restricted earlier efforts to identify them correctly as the cause of disease in aquatic animals. The most information to date relates to disease in cod, caused by F. noatunensis and tilapia, caused by F. noatunensis subsp. orientalis (also termed F. asiatica), both causing granulomatous inflammatory reactions. Mortalities in both species can be high and, as the disease can likely be transferred via live fish movements, they pose a significant threat to tilapia and cod aquaculture operations. Although the fish-pathogenic Francisella species are classified in the same genus as the human pathogens F. tularensis, causative agent of tularemia, and F. philomiragia, the risk to humans from the fish and shellfish pathogenic Francisella species is considered very low. PMID:21306585

Birkbeck, T H; Feist, S W; Verner-Jeffreys, D W

2011-03-01

65

Study of paralytic shellfish poisoning toxin profile in shellfish from the Mediterranean shore of Morocco.  

PubMed

Since 1992, a monitoring program for bivalve molluscs contaminated by algal toxins was established at different stations along the Mediterranean Moroccan shores. The monitored stations were tested every 2 weeks. The presence of toxicity was determined using the mouse bioassay method. Toxin profile was carried out by HPLC/FD in selected contaminated tissues. According to the outcomes of this surveillance from 1994 to 1999, reliable information on toxicity of shellfish was obtained. They indicate that PSP is a recurrent toxicity in molluscs along the Mediterranean shore of Morocco. It has been noted a difference of PSP accumulation among individual shellfish. The cockle (Achanthocardia tuberculatum) presents toxicity throughout the year, while other specimens from the same area such as clam (Callista chione), warty venus (Venus gallina) and marine beans (Donax trunculus) accumulate it seasonally from January to April, after which they depurate the toxin. Moreover, the study of toxin profiles among individual shellfish was undertaken. It was found that shellfish presented a complex profile pointing to contamination by Gymnodinium catenatum. PMID:11600148

Taleb, H; Vale, P; Jaime, E; Blaghen, M

2001-12-01

66

THE OXYGEN REQUIREMENTS OF SHELLFISH By Philip H. Mitchell  

E-print Network

THE OXYGEN REQUIREMENTS OF SHELLFISH ~ By Philip H. Mitchell 2°7 #12;Blank page retained for pagination #12;THE OXYGEN REQUIREMENTS OF SHELLFISH. By PHILIP H. MITCHELL. J1, The respiratory exchanges to temperature changes, a smaller utili- zation of oxygen in proportion to the body weight with increase in size

67

Shellfish aquaculture — In praise of sustainable economies and environments  

Microsoft Academic Search

We write to extol the virtues of filter- feeding bivalve shellfish - clams, mus- sels, oysters and scallops - to give them their due as key players in ecologically sustainable aquaculture in the marine en- vironment and as environmentally sensi- tive monitors and water purifiers. Shell- fish are successfully farmed throughout the world and shellfish culture represents a legitimate use

SANDRA E. SHUMWAY; CHRIS DAVIS; ROBIN DOWNEY; RICK KARNEY; JOHN KRAEUTER; JAY PARSONS; ROBERT RHEAULT; GARY WIKFORS

68

Shellfish Toxins Targeting Voltage-Gated Sodium Channels  

PubMed Central

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

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

2013-01-01

69

Radioimmunoassay of paralytic shellfish toxins in clams and mussels  

SciTech Connect

Shellfish contaminated with paralytic shellfish poisons (PSP) compromise human health. The threat of this contamination results in enormous economic losses in the recreational and commercial exploitation of shellfish resources in the affected areas. Most states deal with the PSP problem either by prohibiting the collection of shellfish during certain time periods or by instituting monitoring programs. The only recognized method of analysis for PSP that is currently and routinely used in monitoring programs is the time-of-death mouse bioassay. Several attempts to develop simple and highly specific biochemical assays for the detection and quantitation of the PSP toxins have been reported. More recently, much improved immunoassays have been developed. To evaluate the validity and usefulness of the immunoassay for the determination of PSP toxins, the authors have used extracts of shellfish gathered from Maine and Connecticut to compare the results of the mouse bioassay and HPLC methods with the radioimmunoassay developed previously.

Yang, G.C.; Imagire, S.J.; Yasaei, P.; Ragelis, E.P.; Park, D.L.; Page, S.W.; Carlson, R.E.; Guire, P.E.

1987-08-01

70

Environmental Transmission of Human Noroviruses in Shellfish Waters  

PubMed Central

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

Lees, David N.

2014-01-01

71

Determination of paralytic shellfish toxins in shellfish by receptor binding assay: collaborative study.  

PubMed

A collaborative study was conducted on a microplate format receptor binding assay (RBA) for paralytic e shellfish toxins (PST). The assay quantifies the composite PST toxicity in shellfish samples based on the ability of sample extracts to compete with (3)H saxitoxin (STX) diHCl for binding to voltage-gated sodium channels in a rat brain membrane preparation. Quantification of binding can be carried out using either a microplate or traditional scintillation counter; both end points were included in this study. Nine laboratories from six countries completed the study. One laboratory analyzed the samples using the precolumn oxidation HPLC method (AOAC Method 2005.06) to determine the STX congener composition. Three laboratories performed the mouse bioassay (AOAC Method 959.08). The study focused on the ability of the assay to measure the PST toxicity of samples below, near, or slightly above the regulatory limit of 800 (microg STX diHCl equiv./kg). A total of 21 shellfish homogenates were extracted in 0.1 M HCl, and the extracts were analyzed by RBA in three assays on separate days. Samples included naturally contaminated shellfish samples of different species collected from several geographic regions, which contained varying STX congener profiles due to their exposure to different PST-producing dinoflagellate species or differences in toxin metabolism: blue mussel (Mytilus edulis) from the U.S. east and west coasts, California mussel (Mytilus californianus) from the U.S. west coast, chorito mussel (Mytilus chiliensis) from Chile, green mussel (Perna canaliculus) from New Zealand, Atlantic surf clam (Spisula solidissima) from the U.S. east coast, butter clam (Saxidomus gigantea) from the west coast of the United States, almeja clam (Venus antiqua) from Chile, and Atlantic sea scallop (Plactopecten magellanicus) from the U.S. east coast. All samples were provided as whole animal homogenates, except Atlantic sea scallop and green mussel, from which only the hepatopancreas was homogenized. Among the naturally contaminated samples, five were blind duplicates used for calculation of RSDr. The interlaboratory RSDR of the assay for 21 samples tested in nine laboratories was 33.1%, yielding a HorRat value of 2.0. Removal of results for one laboratory that reported systematically low values resulted in an average RSDR of 28.7% and average HorRat value of 1.8. Intralaboratory RSDr based on five blind duplicate samples tested in separate assays, was 25.1%. RSDr obtained by individual laboratories ranged from 11.8 to 34.9%. Laboratories that are routine users of the assay performed better than nonroutine users, with an average RSDr of 17.1%. Recovery of STX from spiked shellfish homogenates was 88.1-93.3%. Correlation with the mouse bioassay yielded a slope of 1.64 and correlation coefficient (r(2)) of 0.84, while correlation with the precolumn oxidation HPLC method yielded a slope of 1.20 and an r(2) of 0.92. When samples were sorted according to increasing toxin concentration (microg STX diHCl equiv./kg) as assessed by the mouse bioassay, the RBA returned no false negatives relative to the 800 microg STX diHCl equiv./kg regulatory limit for shellfish. Currently, no validated methods other than the mouse bioassay directly measure a composite toxic potency for PST in shellfish. The results of this interlaboratory study demonstrate that the RBA is suitable for the routine determination of PST in shellfish in appropriately equipped laboratories. PMID:22816272

Van Dolah, Frances M; Fire, Spencer E; Leighfield, Tod A; Mikulski, Christina M; Doucette, Gregory J

2012-01-01

72

Complete Genome Sequence for the Shellfish Pathogen Vibrio coralliilyticus RE98 Isolated from a Shellfish Hatchery  

PubMed Central

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 megaplasmids (380,714 and 319,400 bp). PMID:25523764

Bono, James L.; Watson, Michael A.; Needleman, David S.

2014-01-01

73

Lipophilic shellfish toxins in Dinophysis caudata picked cells and in shellfish from the East China Sea.  

PubMed

We reported previously that okadaic acid (OA) and dinophysistoxin-1 (DTX1) were responsible for diarrhetic shellfish poisoning (DSP) incidents due to consuming cultivated mussels (Mytilus galloprovincialis) in coastal cities near the East China Sea in May 2011. Pectenotoxin-2 (PTX2) and its seco acids were also present in these mussels. Causative species of microalgae were not identified because detailed information on the location of the contaminated shellfish was not recorded. In order to explore potential causes for these poisoning events, the lipophilic toxin profiles in picked cells of Dinophysis and in shellfish samples collected from two mariculture zones in the East China Sea were analyzed in the present study. Single-cell isolates (100 cells total for each location) of Dinophysis were collected from the aquaculture zones of Gouqi Island (Ningbo City, Zhejiang Province) and Qingchuan Bay (Ningde City, Fujian Province) in July and September 2013, respectively, for lipophilic toxin profiling. Shellfish samples collected over the course of a year from the Gouqi Island aquaculture zone and mussels (M. galloprovincialis) collected four times from the Qingchuan Bay aquaculture zone were tested for lipophilic toxins by LC-MS/MS. The Dinophysis cells isolated from both sampling sites were identified under the light microscope as Dinophysis caudata. Average quota of PTX2, the predominant toxin in D. caudata isolated from the coastal waters of Gouqi Island and Qingchuan Bay, was 0.58 and 2.8 pg/cell, respectively. Only trace amounts of OA and DTX1 were detected in D. caudata. PTX2, PTX2sa, 7-epi-PTX2sa, OA, and/or DTX1 were found in samples of mussels (M. galloprovincialis and Mytilus coruscus) collected in the Gouqi Island aquaculture zone from the end of May to the beginning of July 2013. PTX2, PTX2sa, and 7-epi-PTX2sa were also detected in oyster (Crassostrea gigas) during that period, but almost no OA and DTX1 were present. Gymnodimine (GYM) was detected in almost all mussel (M. coruscus) samples, with the highest levels occurring in winter. Trace amounts of pectenotoxins (PTXs) and OAs were also found in mussels (M. galloprovincialis) collected from Qingchuan Bay. D. caudata is suggested as an important source of PTXs in shellfish cultivated in the East China Sea. This is the first report of toxin profiles for single-cell isolates of Dinophysis in the East China Sea. PMID:25233922

Li, Aifeng; Sun, Geng; Qiu, Jiangbing; Fan, Lin

2015-02-01

74

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2010 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2010-10-01

75

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2010 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2010-07-01

76

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2013-10-01

77

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2011 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2011-07-01

78

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2013-07-01

79

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2014 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2014-10-01

80

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2011 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2011-10-01

81

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2012 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2012-10-01

82

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2012 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2012-07-01

83

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2014 CFR

...Dungeness crab, king crab, Tanner crab, shrimp, clams, abalone, and other shellfish or their parts...hook; (iv) A handline; (v) A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring...

2014-07-01

84

Processing Strategies to Inactivate Enteric Viruses in Shellfish  

Microsoft Academic Search

Noroviruses, hepatitis A and E viruses, sapovirus, astrovirus, rotavirus, Aichi virus, enteric adenoviruses, poliovirus, and\\u000a other enteroviruses enter shellfish through contaminated seawater or by contamination during handling and processing, resulting\\u000a in outbreaks ranging from isolated to epidemic. Processing and disinfection methods include shellfish depuration and relaying,\\u000a cooking and heat pasteurization, freezing, irradiation, and high pressure processing. All the methods can

Gary P. Richards; Catherine McLeod; Françoise S. Le Guyader

2010-01-01

85

Surveillance of algal toxins in shellfish from Scottish waters.  

PubMed

Shellfish samples were collected from coastal and offshore aquaculture sites and harvesting areas in Scottish waters between March 2003 and September 2004. Samples were analysed for the presence of algal toxins using traditional mouse bioassays for the detection of paralytic shellfish poisoning (PSP) toxins and diarrhetic shellfish poisoning (DSP) toxins; immuno-lateral flow chromatography for the detection of PSP toxins in the form of the Jellett Rapid Test; high-performance liquid chromatography (HPLC) with UV diode-array for the detection of amnesic shellfish poisoning (ASP) toxins; and liquid chromatography with mass spectrometry (LC-MS) for the detection of multiple lipophilic shellfish toxins (LSTs) including pectenotoxins (PTXs), yessotoxins (YTXs), azaspiracids (AZAs) and toxins from the 'traditional' DSP toxin group, okadaic acid (OA) and dinophysistoxins (DTXs). In order to investigate the presence of OA esters, alkaline hydrolysis was performed. All toxin groups were detected with a geographically widespread distribution. ASP toxins were the most prevalent occurring in 69% of samples. Using the PSP mouse bioassay, PSP toxins were detected in 5% of shellfish samples from coastal waters around the islands and the east coast. The Jellett Rapid Test for PSP toxins revealed a wider distribution (24% of samples) including the west coast of Scotland. Toxins from the 'traditional' DSP toxin group (OA/DTXs) and/or other LST groups (PTXs, YTXs and AZAs) were detected by LC-MS in 63% of the shellfish analysed. PSP, ASP toxins and LSTs occurred concurrently in a limited sample set, highlighting the importance of using methods capable of detecting multiple algal toxin groups in Scottish shellfish monitoring programmes. PMID:18207483

Stobo, L A; Lacaze, J-P C L; Scott, A C; Petrie, J; Turrell, E A

2008-03-15

86

Polybrominated anisoles in marine fish, shellfish, and sediments in Japan  

Microsoft Academic Search

The concentrations of polybrominated anisoles (2,4-dibromoanisole, 2,4,6-tribromoanisole and pentabromoanisole) were determined in marine fish, shellfish, and sediments collected in Japan. 2,4,6-Tribromoanisole was found in fourteen of 24 fish and shellfish samples, with a range of 0.1–5.4 (?g\\/kg (ppb) on a wet weight basis. The concentrations of 2,4,6-tribromoanisole were similar to pentachloroanisole and hexachlorobenzene but about one-hundredth of those of polychlorinated

Isao Watanabe; Takashi Kashimoto; Ryo Tatsukawat

1983-01-01

87

Surveillance of Hepatitis E Virus Contamination in Shellfish in China  

PubMed Central

Background: Hepatitis E virus (HEV) has been confirmed to be a zoonotic virus of worldwide distribution. HEV contamination in the water environment has not been well examined in China. The objective of this study was to evaluate HEV contamination in shellfish in a coastal area of China. Such contamination would be significant for evaluating public health risks. Methods: samples of three species shellfish were collected from thirteen points of estuarine tidal flats around the Bohai Gulf and screened for HEV RNA using an in-house nested RT-PCR assay. The detected HEV-positive samples were further verified by gene cloning and sequencing analysis. Results: the overall HEV-positive detection rate is approximately 17.5% per kilogram of shellfish.  HEV was more common among S. subcrenata (28.2%), followed by A. granosa (14.3%) and R. philippinarum (11.5%). The phylogenetic analysis of the 13 HEV strains detected revealed that gene fragments fell into two known 4 sub-genotypes (4b/4d) groups and another unknown group. Conclusions: 13 different sub-genotype 4 HEVs were found in contaminated shellfish in the Bohai Gulf rim. The findings suggest that a health risk may exist for users of waters in the Bonhai area and to consumers of shellfish.  Further research is needed to assess the sources and infectivity of HEV in these settings, and to evaluate additional shellfish harvesting areas. PMID:25689991

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

2015-01-01

88

RIBBED MUSSEL NITROGEN ISOTOPE SIGNATURES REFLECT NITROGEN SOURCES IN COASTAL MARSHES  

EPA Science Inventory

The stable nitrogen isotope ratio in tissue of the ribbed mussel (Geukensia demissa) was investigated as an indicator of the source of nitrogen inputs to coastal salt marshes. Initially, mussels were fed a diet of 15N-enriched algae in the laboratory to determine how the tissue n...

89

COMPARISON OF RIBBED MUSSEL POPULATIONS IN MARSHES SUBJECT TO INCREASING LAND USAGE AND NUTRIENT LOADING  

EPA Science Inventory

Abstract: Narragansett Bay salt marshes of similar geomorphology and hydrology were clustered into low, medium and high human impact based on land use and nutrient inputs. We measured abundance, condition index (CI) and growth of ribbed mussels (Geukensia demissa) from 10 salt ma...

90

As required by the Interstate Shellfish Sanitation Conference, National Shellfish Sanita-tion Program, harvesting of bivalve (filter-feeding) shellfish is prohibited in an area  

E-print Network

Program, harvesting of bivalve (filter-feeding) shellfish is prohibited in an area when concentrations of killing fish, birds, and other marine animals. Brevetoxins may also cause health problems in humans are tested for toxicity during that period, and the harvesting ban is lifted when test results verify

Florida, University of

91

National collaborative shellfish pollution-indicator study: Site selection. Phase 2. Rept. for 1988-89  

SciTech Connect

Each year, about 16 million areas of estuarine waters are classified for the harvest of molluscan shellfish as open or limited to harvest according to microbiological 'indicator' standards and pollution survey guidelines established by the National Shellfish Sanitation Program. The program was developed in the 1920s in response to typhoid fever outbreaks associated with shellfish consumption. Current microbiological indicator standards in shellfish and shellfish-growing waters are extrpolated from standards set in the 1920s. Results from studies in the last decade have indicated that these microbiological indicator standards and thus classification of shellfish-growing waters may no longer be valid. The National Collaborative Shellfish Pollution Indicator Study is proposed as a four-year study to evaluate the current relationships between indicators of human enteric pathogens and the incidence of shellfish-borne diseases. Tasks forces were established to address specific issues, including site selection, shoreline surveys, and laboratory methodologies.

Leonard, D.L.; Slaughter, E.A.; Corning, B.C.

1990-07-01

92

HIGH HYDROSTATIC PRESSURE PROCESSING: A POTENTIAL SOLUTION FOR SHELLFISH-BORNE VIRUSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Molluscan shellfish bioconcentrate enteric viruses from human wastes that are present in the growing waters. Consequently, the consumption of raw shellfish poses considerable risk for contracting illnesses associated with these viruses. High hydrostatic pressure is a new nonthermal sanitizing proc...

93

Prevalence of Arcobacter in meat and shellfish.  

PubMed

Arcobacter is considered an emergent foodborne and waterborne enteropathogen. However, its prevalence in foods of animal origin is only partially known, because most studies have been concentrated on poultry, pork, and beef, and methods applied do not allow identification of all currently accepted Arcobacter species. We investigated the prevalence of Arcobacter in 203 food samples, 119 samples of seven different types of meats and 84 samples of four types of shellfish. Isolates were identified in parallel by using a published multiplex PCR method and a recently described 16S rDNA restriction fragment length polymorphism method that allows all currently accepted Arcobacter species to be characterized. The global prevalence of Arcobacter was 32%; it was highest in clams (5 of 5 samples, 100%) and chicken (9 of 14 samples, 64.3%) followed by pork (9 of 17 samples, 53.0%), mussels (23 of 56 samples, 41.1%), and duck meat (2 of 5 samples, 40.0%). Turkey meat and beef had a similar recovery rate (10 of 30 samples, 33.3%; 5 of 16 samples, 31.3%; respectively), and rabbit meat had the lowest rate (1 of 10 samples, 10.0%). No arcobacters were found in oysters, frozen shrimps, or sausages. This food survey is the first in which five of the seven accepted Arcobacter species have been isolated. Arcobacter butzleri was the most prevalent species (63.0% of isolates) followed by Arcobacter cryaerophilus (26.6%), Arcobacter mytili (4.7%), Arcobacter skirrowii (3.1%), and Arcobacter nitrofigilis (3.1%). Three (4.7%) of the isolates were classified as belonging to three potentially new phylogenetic lines. Our results indicated that Arcobacter species are widely distributed in the food products studied. PMID:19517742

Collado, Luis; Guarro, Josep; Figueras, Maria José

2009-05-01

94

Shellfish Fishery Severely Reduces Condition and Survival of Oystercatchers Despite Creation of Large Marine Protected Areas  

Microsoft Academic Search

Fisheries and other human activities pose a global threat to the marine environment. Marine protected areas (MPAs) are an emerging tool to cope with such threats. In the Dutch Wadden Sea, large MPAs (covering 31% of all intertidal flats) have been created to protect shellfish-eating birds and allow recovery of important habitats. Even though shellfish fishing is prohibited in these

Simon Verhulst; Kees Oosterbeek; Anne L. Rutten; Bruno J. Ens

2004-01-01

95

Evaluation of Potential Indicators of Viral Contamination in Shellfish and Their Applicability to Diverse Geographical Areas  

Microsoft Academic Search

The distribution of the concentration of potential indicators of fecal viral pollution in shellfish was analyzed under diverse conditions over 18 months in diverse geographical areas. These microorganisms have been evaluated in relation to contamination by human viral pathogens detected in parallel in the analyzed shellfish samples. Thus, significant shellfish-growing areas from diverse countries in the north and south of

M. Formiga-Cruz; A. K. Allard; A.-C. Conden-Hansson; K. Henshilwood; B. E. Hernroth; J. Jofre; D. N. Lees; F. Lucena; M. Papapetropoulou; R. E. Rangdale; A. Tsibouxi; A. Vantarakis; R. Girones

2003-01-01

96

When enough is not enough: shorebirds and shellfishing.  

PubMed Central

In a number of extensive coastal areas in northwest Europe, large numbers of long-lived migrant birds eat shellfish that are also commercially harvested. Competition between birds and people for this resource often leads to conflicts between commercial and conservation interests. One policy to prevent shellfishing from harming birds is to ensure that enough food remains after harvesting to meet most or all of their energy demands. Using simulations with behaviour-based models of five areas, we show here that even leaving enough shellfish to meet 100% of the birds' demands may fail to ensure that birds survive in good condition. Up to almost eight times this amount is needed to protect them from being harmed by the shellfishery, even when the birds can consume other kinds of non-harvested prey. PMID:15058432

Goss-Custard, J. D.; Stillman, R. A.; West, A. D.; Caldow, R. W. G.; Triplet, P.; le V dit Durell, S. E. A.; McGrorty, S.

2004-01-01

97

Organochlorine residues in shellfish from Maryland waters, 1976-1980.  

PubMed

Shellfish samples, including the American oyster (Craessostrea virginica), the soft shell clam (Mya arenaria), the hard shell clam (Mercenaria mercenaria) and the blue crab (callinectes sapidus), were taken from the Maryland section of the Chesapeake Bay and its tributaries over a five year period (1976-80) and analyzed to determine residue levels of various organochlorine pesticides. Qualitative and quantitative information was obtained for a variety of polychlorinated hydrocarbons. The purpose of this study includes the establishment of baseline values for levels of shellfish contamination, utilization of the data as an indicator of probable levels of water and sediment contamination in the vicinity of the sampling site and ensurance that shellfish harvested for human consumption are within U.S. Food and Drug Administration guidelines for organochlorine contamination. All mean values and virtually all individual values were within FDA guidelines. PMID:6501793

Eisenberg, M; Topping, J J

1984-10-01

98

Recreational Shellfish Beach Closures Due to Biotoxins or Pollution  

NSDL National Science Digital Library

This map represents the Health Status of beaches in the state of Washington. The interactive map allows users to click on counties, water bodies, and beaches to view seasons and limits. The page also includes links to text bulletins regarding beach closures, descriptions of marine biotoxins and associated health effects, and a factsheet of shellfish program publications.

Washington State Department of Health

99

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...

100

Dinophysis Toxins: Causative Organisms, Distribution and Fate in Shellfish  

PubMed Central

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

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

2014-01-01

101

Enteric porcine viruses in farmed shellfish in Denmark.  

PubMed

Bivalve shellfish are at constant risk of being exposed to pathogens as a consequence of contamination of the shellfish beds with human or animal waste originating from sewage treatment plants or slurry fertilized fields. Consumption of contaminated oysters and mussels are frequently reported as causes of disease outbreaks caused by norovirus or hepatitis A virus. Other zoonotic pathogens such as hepatitis E virus (HEV), rotavirus (RV) and Salmonella from livestock may also be transmitted to shellfish via this route. In this study, 29 pooled samples from commercial Danish blue mussels were tested for porcine pathogens and indicator bacteria Escherichia coli (E. coli). All samples tested negative for HEV, RV and Salmonella, whereas E. coli and the highly stable porcine circovirus type 2 (PCV2) were detected in eight and 12 samples, respectively. This is the first study to report the detection of PCV2 in commercial mussels. Based on the detection of PCV2 in clean areas with low prevalence of the normally applied fecal indicator E. coli, testing for PCV2 may be a more sensitive and robust specific porcine waste indicator in shellfish harvesting areas. PMID:25016209

Krog, J S; Larsen, L E; Schultz, A C

2014-09-01

102

Presence of Salmonella spp. and Campylobacter spp. in shellfish.  

PubMed Central

Bivalve molluscs, (cockles, mussels, scallops and oysters) were examined according to EC shellfish bed classification regulations for faecal coliforms, Escherichia coli and salmonella, and for coliforms and campylobacter which are not specified by these regulations. Salmonella serotypes were detected in 8% of 433 molluscs. Seven salmonella isolations (2%) were made from category A beds, nominally suitable for immediate consumption according to E. coli counts. A higher percentage of salmonella isolates (6%) was detected in shellfish which require relaying or depuration prior to eating. In another survey, thermophilic Campylobacter spp. were found in 42% of 380 shellfish. These findings show bed classification on the basis of indicator organisms alone is not sufficient to assure the absence of bacterial, and no doubt viral, pathogens. Depuration and end product specifications which require the absence of salmonellae are an essential part of these regulations. Microbiologists may wish to consider whether tests for pathogens such as salmonella and campylobacter should be included when determining the suitability of shellfish for human consumption. PMID:8620905

Wilson, I. G.; Moore, J. E.

1996-01-01

103

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...

104

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 ...

105

A highly rapid and simple competitive enzyme-linked immunosorbent assay for monitoring paralytic shellfish poisoning toxins in shellfish.  

PubMed

Using a streptavidin-coated well plate, a biotin-labelled anti-gonyautoxin 2/3 monoclonal antibody GT-13A, and a decarbamoyl saxitoxin-peroxidase conjugate, a direct competitive enzyme-linked immunosorbent assay (PSP-ELISA) was developed for monitoring paralytic shellfish poisoning (PSP) toxins in shellfish. This assay is simple to perform and can be completed in approximately 20 min. The PSP-ELISA was compared to the mouse bioassay (MBA) for the detection of PSP toxins in shellfish samples (n=83) collected from the coast of Osaka Prefecture, Japan. When positive and negative results were indicated based on the regulatory limit for PSP toxins (4 mouse unit(MU)/g of shellfish meat), the PSP-ELISA results showed a sensitivity of 100% (25 of 25) and a specificity of 89.7% (52 of 58 samples) compared to the MBA results. These results suggest that the PSP-ELISA could be used as a rapid and simple screening method prior to the MBA. PMID:24874362

Kawatsu, Kentaro; Kanki, Masashi; Harada, Tetsuya; Kumeda, Yuko

2014-11-01

106

Evolving to the optoelectronic mouse for phycotoxin analysis in shellfish.  

PubMed

Despite ethical and technical concerns, the in vivo method, or more commonly referred to mouse bioassay (MBA), is employed globally as a reference method for phycotoxin analysis in shellfish. This is particularly the case for paralytic shellfish poisoning (PSP) and emerging toxin monitoring. A high-performance liquid chromatography method (HPLC-FLD) has been developed for PSP toxin analysis, but due to difficulties and limitations in the method, this procedure has not been fully implemented as a replacement. Detection of the diarrhetic shellfish poisoning (DSP) toxins has moved towards LC-mass spectrometry (MS) analysis, whereas the analysis of the amnesic shellfish poisoning (ASP) toxin domoic acid is performed by HPLC. Although alternative methods of detection to the MBA have been described, each procedure is specific for a particular toxin and its analogues, with each group of toxins requiring separate analysis utilising different extraction procedures and analytical equipment. In addition, consideration towards the detection of unregulated and emerging toxins on the replacement of the MBA must be given. The ideal scenario for the monitoring of phycotoxins in shellfish and seafood would be to evolve to multiple toxin detection on a single bioanalytical sensing platform, i.e. 'an artificial mouse'. Immunologically based techniques and in particular surface plasmon resonance technology have been shown as a highly promising bioanalytical tool offering rapid, real-time detection requiring minimal quantities of toxin standards. A Biacore Q and a prototype multiplex SPR biosensor have been evaluated for their ability to be fit for purpose for the simultaneous detection of key regulated phycotoxin groups and the emerging toxin palytoxin. Deemed more applicable due to the separate flow channels, the prototype performance for domoic acid, okadaic acid, saxitoxin, and palytoxin calibration curves in shellfish achieved detection limits (IC20) of 4,000, 36, 144 and 46 ?g/kg of mussel, respectively. A one-step extraction procedure demonstrated recoveries greater than 80% for all toxins. For validation of the method at the 95% confidence limit, the decision limits (CC?) determined from an extracted matrix curve were calculated to be 450, 36 and 24 ?g/kg, and the detection capability (CC?) as a screening method is ?10 mg/kg, ?160 ?g/kg and ?400 ?g/kg for domoic acid, okadaic acid and saxitoxin, respectively. PMID:25245418

Campbell, Katrina; McNamee, Sara E; Huet, Anne-Catherine; Delahaut, Philippe; Vilarino, Natalia; Botana, Luis M; Poli, Mark; Elliott, Christopher T

2014-11-01

107

Liquid Chromatographic Determination of Amnesic Shellfish Poison in Mussels  

NASA Astrophysics Data System (ADS)

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.

Duxbury, Mark

2000-10-01

108

Microbial reclamation of shellfish wastes for the production of chitinases  

Microsoft Academic Search

Shrimp and crab shell powder (SCSP), prepared by treating shellfish processing waste with boiling and crushing, was used as a substrate for isolating chitinolytic microorganisms. Three potential strains (E1, J1, and J1-1) were isolated and identified as Bacillus cereus, B. alvei, and B. sphaericus, respectively. Three extracellular chitinases (FB1, FB2, and FB3) were purified from the culture supernatants of Bacillus

San-Lang Wang; Jau-Ren Hwang

2001-01-01

109

Aquaculture and environmental stewardship: Milford shellfish biology seminar—1991  

NASA Astrophysics Data System (ADS)

For the past 11 years the annual Shellfish Biology Seminar at Milford CT has provided a unique forum for aquaculture scientists and industry officials to exchange information about estuaries facing increased pollution problems, especially Long Island Sound and the Great South Bay. Because these two areas are so rich in productivity and diversity, fish and shellfish farmers utilize their waters, shellfish beds, and shore land for hatcheries and grow-out facilities. These individuals seek better management of the coastal estuarine environment and its resources, providing a working example of environmental stewardship. In aquaculture, good science is required to understand the complex variables and interaction of estuarine currents, tides, temperature, and cycles of reproduction. Aquaculturists are beginning to understand the need for specific nutrients and how the wastes of one species can be utilized for enhanced production of another species. Over the years, this meeting has formed an amalgam of both the aquaculture industry and research scientists where both groups foster mutual environmental concern. Science is able to focus on the theoretical aspects of pollutant damage. while the aquaculture industry is able to define the problem and need for assistance to eliminate pollutants from their crops—shellfish and finfish. Overfishing is not an issue at these meetings, as the group accepts the damage already done to wild resources and seeks new technologies to grow food sources under controlled and stable market conditions. Therefore, it could be said that the seminar serves as a meeting ground where the theoretical knowledge of scientific study finds practical application in the industry and is fueled by the needs of that industry. This ideal blend of the two groups produces better management of the resource and a safer environment—the goal of stewardship.

Blogoslawski, Walter J.

1992-07-01

110

Impact of xynthia tempest on viral contamination of shellfish.  

PubMed

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

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

2012-05-01

111

Shellfish: Toxicology studies. (Latest citations from the NTIS Bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the effects of toxic substances on shellfish. Petroleum products, solvents, sewage, copper, mercury, chromium, dredged materials, and organic chemicals are among the toxic substances studied. Reproductive impairment, molting behavior, and population reduction caused by toxic chemicals are discussed. Shellfish as bioindicators and shellfish tolerance to toxic substances are briefly considered. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-12-01

112

Comparative analysis of modeled nitrogen removal by shellfish farms.  

PubMed

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

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

2015-02-15

113

Studies in the use of magnetic microspheres for immunoaffinity extraction of paralytic shellfish poisoning toxins from shellfish.  

PubMed

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

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

2011-01-01

114

Shellfish: toxicology studies. October 1982-May 1988 (Citations from the NTIS data base). Report for October 1982-May 1988  

SciTech Connect

This bibliography contains citations concerning the effects of toxic substances on shellfish. Petroleum products, solvents, sewage, copper, mercury, chromium, dredged materials, and organic chemicals are among the toxic substances studied. Reproductive impairement, molting behavior, and population reduction caused by toxic chemicals are discussed. Shellfish as bioindicators and shellfish tolerance to toxic substances are briefly considered. Shellfish farming and economics are covered in a separate bibliography. (Contains 108 citations fully indexed and including a title list.)

Not Available

1988-05-01

115

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

Federal Register 2010, 2011, 2012, 2013, 2014

...conservation and restoration of Puget Sound, has set a priority to reduce...to restore and protect Puget Sound, has set a goal for a net increase...goal, the Northwest Fisheries Science Center is undertaking an economics...shellfish harvesting. The Puget Sound Recreational Shellfish...

2012-06-18

116

Molecular Characterization of Hepatitis A Virus Isolates from a Transcontinental Shellfish-Borne Outbreak  

Microsoft Academic Search

One hundred eighty-four serologically confirmed cases of hepatitis A were reported in eastern Spain in 1999. A matched case-control study implicated imported coquina clams complying with European Union shellfish standards as the source of infection; this implication was confirmed by the detection by reverse transcription- PCR of hepatitis A virus (HAV) RNA in shellfish samples. In spite of the recognized

Gloria Sanchez; Rosa M. Pinto; Hermelinda Vanaclocha; Albert Bosch

2002-01-01

117

Chemical Risks Associated with Consumption of Shellfish Harvested on the North Shore of the St. Lawrence River's Lower Estuary  

Microsoft Academic Search

In addition, we analyzed samples of shellfish harvested in this area to determine the nature and levels of the chemical contamination. We also aimed to assess the cancer and noncancer risks associated with consumption of shellfish harvested in this area. Shellfish have the capacity to accumulate chemical contaminants found in their biotope and there- fore present a potential risk for

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

2004-01-01

118

An RNA extraction protocol for shellfish-borne viruses.  

PubMed

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-1), and the norovirus surrogate, feline calicivirus (FCV) strain KCD, for the purpose of RT-PCR detection within seeded oyster (Crassostrea virginica) extracts. The RT-PCR equivalent sensitivities observed within seeded oysters as compared to virus stocks were 0.68, 6.8, 26, 5.6, and 14.5 RT-PCR(50) units when assaying 10% of total RNA extracted from seeded oyster extracts for CAV9, CBV5, AiV, FCV, and MNV-1, respectively. For oysters exposed to virus-contaminated seawater, the detection equivalent sensitivities observed were 680, 68, 2600, 560, and 14.5 RT-PCR(50) for CAV9, CBV5, AiV and FCV, and MNV-1, respectively. These results indicate that the GPTT method can be used as a general viral RNA extraction method for multiple picornaviruses and caliciviruses that could potentially contaminate shellfish. PMID:17184849

Kingsley, David H

2007-04-01

119

Enteric viruses in a mangrove lagoon, survival and shellfish incidence  

SciTech Connect

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.

Lopez de Cardona, I.; Bermudez, M.; Billmire, E.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico)

1988-12-31

120

Azaspiracid poisoning (AZP) toxins in shellfish: toxicological and health considerations.  

PubMed

It has been almost a decade since a previously unknown human toxic syndrome, azaspiracid poisoning (AZP), emerged as the cause of severe gastrointestinal illness in humans after the consumption of mussels (Mytilus edulis). Structural studies indicated that these toxins, azaspiracids, were of a new unprecedented class containing novel structural features. It is now known that the prevalent azaspiracids in mussels are AZA1, AZA2 and AZA3, which differ from each other in their degree of methylation. Several hydroxylated and carboxylated analogues of the main azaspiracids have also been identified, presumed to be metabolites of the main toxins. Since its first discovery in Irish mussels, the development of facile sensitive and selective LC-MS/MS methods has resulted in the discovery of AZA in other countries and in other species. Mice studies indicate that this toxin class can cause serious tissue injury, especially to the small intestine, and chronic exposure may increase the likelihood of the development of lung tumours. Studies also show that tissue recovery is very slow following exposure. These observations suggest that AZA is more dangerous than the other known classes of shellfish toxins. Consequently, in order to protect human consumers, proper risk assessment and regulatory control of shellfish and other affected species is of the utmost importance. PMID:20026101

Furey, Ambrose; O'Doherty, Sinead; O'Callaghan, Keith; Lehane, Mary; James, Kevin J

2010-08-15

121

Shellfish Disease in Aquaculture: Scientists, Managers, and Growers Take on the Challenges  

NSDL National Science Digital Library

This "Two if by Sea" newsletter article highlights proceedings from a workshop in 2000 that focused on shellfish disease, particularly as it relates to the aquaculture industry. Speakers, including pathologists, growers, and industry representatives, delivered a recurring message: shellfish diseases are not only here, they are here to stay. And, most likely, they concur, additional diseases will be discovered in the future. The article discusses the following shellfish diseases: MSX (multinucleated sphere unknown), dermo (short for Dermocystidium marinus, the initial classification of the parasite that causes the disease; the parasite was later found to be of the genus Perkinsus), JOD (juvenile oyster disease), and QPX (Quahog Parasite Unknown).

Tracey Crago

122

Risk Assessment in Shellfish-Borne Outbreaks of Hepatitis A?  

PubMed Central

In the present work, we aimed at determining the relationship between the hepatitis A virus (HAV) numbers in imported frozen coquina clams involved in two hepatitis outbreaks, as well as the risk for human health. Due to HAV unculturability, a standardized TaqMan real-time reverse transcription-PCR controlling the virus/nucleic acid extraction and enzyme efficiencies was employed to figure the exposure dose for clams responsible for hepatitis cases. HAV numbers were then employed to figure the risk of infection based on a dose-response model for echovirus 12. The estimated risk of infection after consumption of lightly cooked clams matched actual attack rates. Our data show that prospective monitoring of bivalve samples may fail to prevent the occurrence of outbreaks, since HAV was detected in 44% of samples directly associated with cases but was undetectable in samples that were randomly collected from the importers and belonged to the same batches. A correlation was nevertheless observed between the prevalence of hepatitis A cases in the harvesting areas and positive HAV isolation in clams, which points to the need to identify and prevent hazards rather than relying on random sampling of finished products to ensure safety. However, when evidence shows that a critical limit of viral contamination has been exceeded in the potential sources of contamination discharging into the shellfish-growing beds, quantitative virological analysis addressing quality assurance and quality control requirements should be performed with the bivalves. This work provides the first evidence of accurate HAV levels in shellfish involved in outbreaks that could be of use for risk assessment purposes. PMID:19820160

Pintó, Rosa M.; Costafreda, M. Isabel; Bosch, Albert

2009-01-01

123

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

PubMed Central

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

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

2013-01-01

124

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....

125

Anja Robinson Fellowship Purpose: To provide support for graduate students doing shellfish aquaculture  

E-print Network

aquaculture research at the Hatfield Marine Science Center in Newport. Approximately $800 will be awarded and potential of proposed research to shellfish aquaculture); use of HMSC facilities; academic and research

126

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...

127

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. FDA-2011-N-0010] Cooperative Agreement To Support Shellfish Safety...its intent to award a single source cooperative agreement to support the Interstate...Conference (ISSC). The purpose of this cooperative agreement is to enhance the FDA...

2011-06-28

128

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 ...

129

Levels and distribution of organochlorine pesticides in shellfish from Qiantang River, China.  

PubMed

Various shellfish collected from different locations along the Qiantang River in 2006 were analyzed for the levels of 13 organochlorine pesticides (OCPs) in order to elucidate the status of OCPs pollution in shellfish for human consumption. Total concentrations of OCPs in shellfish ranged from 16.9 to 78.6 ng/g wet weight (ww), with HCHs (alpha-, beta-, gamma-, delta-HCH), DDTs (p,p'-DDD, p,p'-DDE, p,p'-DDT, o,p'-DDD) and other OCPs (aldrin, diedrin, endrin, heptachlor and heptachlor epoxide) in the range of 3.33-13.2, 8.38-40.1 and 2.32-14.3 ng/g ww, respectively. The dominant OCPs in shellfish were p,p'-DDE among DDTs, beta-HCH among HCHs and heptachlor epoxide among other OCPs. It is noticeable that higher OCPs biota-sediment accumulation factor (BSAF) occurred at site with high concentration of OCPs in sediments. The field bioconcentration factor (BCF) increased exponentially with the increase of Kow (octanol-water partition coefficients) of the OCPs. Concentrations of DDTs and HCHs in shellfish from Qiantang River kept at middle level compared with those from marine environment. The concentrations of DDTs in more than 50% of edible shellfish in this study were higher than the limit of 14.4 ng/g ww for human consumption recommended by US EPA (2000). PMID:17825984

Zhou, Rongbing; Zhu, Lizhong; Kong, Qingxia

2008-04-15

130

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

NASA Astrophysics Data System (ADS)

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.

Crane, Stuart R.; Moore, James A.

1986-01-01

131

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

PubMed Central

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

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

2013-01-01

132

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

PubMed

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, contained 33.9 and 34.5 microg/kg BaP equivalents; all other samples had less than 10 microg/kg BaP equivalents. An evaluation of the PAH profiles in the two higher oyster samples indicated a primary source other than the New Carissa oil. Because shellfish sample BaP equivalents attributable to the New Carissa oil spill did not exceed 10 microg/kg, shellfish harvesting was reopened on 4 March 1999. This study revealed some of the inherent difficulties in attempting to quantify health risks from contaminated shellfish following an oil spill and demonstrated the clear need for standardized protocols for responding to such events. PMID:10912585

Gilroy, D J

2000-07-14

133

Paralytic shellfish toxins inhibit copper uptake in Chlamydomonas reinhardtii.  

PubMed

Paralytic shellfish toxins are secondary metabolites produced by several species of dinoflagellates and cyanobacteria. Known targets of these toxins, which typically occur at detrimental concentrations during harmful algal blooms, include voltage-gated ion channels in humans and other mammals. However, the effects of the toxins on the co-occurring phytoplankton community remain unknown. The present study examined the molecular mechanisms of the model photosynthetic alga Chlamydomonas reinhardtii in response to saxitoxin exposure as a means of gaining insight into the phytoplankton community response to a bloom. Previous work with yeast indicated that saxitoxin inhibited copper uptake, so experiments were designed to examine whether saxitoxin exhibited a similar mode of action in algae. Expression profiling following exposure to saxitoxin or a copper chelator produced similar profiles in copper homeostasis genes, notably induction of the cytochrome c6 (CYC6) and copper transporter (COPT1, CTR1) genes. Cytochrome c6 is used as an alternative to plastocyanin under conditions of copper deficiency, and immunofluorescence data showed this protein to be present in a significantly greater proportion of saxitoxin-exposed cells compared to controls. Live-cell imaging with a copper-sensor probe for intracellular labile Cu(I) confirmed that saxitoxin blocked copper uptake. Extrapolations of these data to phytoplankton metabolic processes along with the copper transporter as a molecular target of saxitoxin based on existing structural models are discussed. PMID:23423950

Cusick, Kathleen D; Wetzel, Randall K; Minkin, Steven C; Dodani, Sheel C; Wilhelm, Steven W; Sayler, Gary S

2013-06-01

134

Removal of Paralytic Shellfish Toxins by Probiotic Lactic Acid Bacteria  

PubMed Central

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

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

2014-01-01

135

Removal of paralytic shellfish toxins by probiotic lactic acid bacteria.  

PubMed

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

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

2014-01-01

136

Concentration and detection of hepatitis A virus and rotavirus from shellfish by hybridization tests.  

PubMed Central

A modified polyethylene glycol precipitation method for concentration of virus followed by a new method to recover nucleic acid was used to detect hepatitis A virus (HAV) and rotavirus (SA11) in shellfish (oysters and hard-shell clams) by hybridization tests. Infectious virus, seeded into relatively large quantities of shellfish, was recovered consistently, with greater than 90% efficiency as measured by either in situ hybridization (HAV) or plaque assay (rotavirus SA11). Viral nucleic acid for dot blot hybridization assays was extracted and purified from virus-containing polyethylene glycol concentrates. Separation of shellfish polysaccharides from nucleic acid was necessary before viral RNA could be detected by dot blot hybridization. Removal of shellfish polysaccharides was accomplished by using the cationic detergent cetyltrimethylammonium bromide (CTAB). Use of CTAB reduced background interference with hybridization signals, which resulted in increased hybridization test sensitivity. After polysaccharide removal, dot blot hybridization assays could detect approximately 10(6) physical particles (corresponding to approximately 10(3) infectious particles) of HAV and 10(4) PFU of SA11 rotavirus present in 20-g samples of oyster and clam meats. These studies show continuing promise for the development of uniform methods to directly detect human viral pathogens in different types of shellfish. However, practical applications of such methods to detect noncultivatable human viral pathogens of public health interest will require additional improvements in test sensitivity. Images PMID:1660697

Zhou, Y J; Estes, M K; Jiang, X; Metcalf, T G

1991-01-01

137

Nested multiplex PCR assay for detection of human enteric viruses in shellfish and sewage.  

PubMed

Environmental samples and contaminated shellfish present frequently low concentrations of more than one viral species. For this reason, a nested multiplex RT-PCR was developed for the detection of adenoviruses, enteroviruses and hepatitis A viruses in different environmental samples such as urban sewage and shellfish. This assay will save time and cost for detection of these enteric viruses with a smaller sample volume, which otherwise can be a limiting factor in routine analysis. The limit of detection was approximately 1 copy for adenovirus and 10 copies for enterovirus and hepatitis A virus per PCR reaction using titrated cell-cultured viruses as template material. In shellfish and environmental samples, this multiplex PCR was optimized to detect all three viruses simultaneously when the concentration of each virus was equal or lower than 1000 copies per PCR reaction. This is the level found predominantly in the environment and in shellfish when the numbers of fecal bacterial and phage indicators are low. The detection of human adenoviruses by PCR has been suggested as a molecular index of fecal contamination of human origin in the environment and food and the multiplex assay developed may be a tool for evaluating the presence of viral contamination in shellfish and water and to expand microbiological control to include viral markers. PMID:15794979

Formiga-Cruz, Meritxell; Hundesa, Ayalkibet; Clemente-Casares, Pilar; Albiñana-Gimenez, Nestor; Allard, Annika; Girones, Rosina

2005-05-01

138

Detection of small round structured viruses in shellfish by reverse transcription-PCR.  

PubMed Central

We describe the application of a previously developed sample extraction procedure to the detection of small round structured viruses (SRSVs) in shellfish. Initial seeding experiments showed that PCR inhibitor removal and virus recoveries were comparable to those in previous studies with poliovirus. Shellfish from a range of sewage-contaminated sites were then tested for the presence of SRSVs by using broadly reactive PCR primers followed by Southern blotting with internal probe sites. Positive results were obtained from 5 of 31 field samples tested. Four of these positive samples were from highly polluted sites. PCR product sequence analysis confirmed their identity as SRSV and showed sequence diversity compared with virus controls, suggesting that the results were not a consequence of PCR cross-contamination. Finally, shellfish associated with four separate outbreaks of viral gastroenteritis were tested by PCR and Southern blot for the presence of SRSVs. All outbreak samples tested gave positive results. As far as we are aware, this is the first demonstration of the detection in environmentally contaminated shellfish of the SRSVs responsible for human gastroenteritis. This development may help contribute to the further development of public health controls for molluscan shellfish. PMID:8534105

Lees, D N; Henshilwood, K; Green, J; Gallimore, C I; Brown, D W

1995-01-01

139

Studies on heat inactivation of hepatitis A virus with special reference to shellfish  

PubMed Central

The consumption of bi-valve molluscan shellfish has been associated with outbreaks of viral gastroenteritis and hepatitis A. Investigations were undertaken to determine the heat inactivation conditions necessary to render shellfish such as cockles safe for the consumer. Conditions for the laboratory maintenance of live cockles are described. In preliminary experiments either poliovirus (106 TCID50/ml seawater) or hepatitis A virus (HAV) (approx. 104 RFU/ml seawater) was introduced into the shellfish tank. Following 48 h filter feeding, virus was recovered from cockles using an adsorption-elution extraction procedure. Titres of virus recovered ranged from 104 to 105 TCID50/ml of shellfish extract for poliovirus and from 103 to 105 RFU/ml of shellfish extract for HAV. Active ingestion of the virus from the seawater was demonstrated by recovering virus from within cockle guts. To quantify recovered HAV, end-point dilutions and an adaptation of a radioimmunofocus assay (RIFA) were compared. The tests were of similar sensitivity but the RIFA has the advantage of being relatively rapid, shortening the time taken to complete an experiment by as much as 4 weeks. ImagesFig. 3Fig. 2 PMID:3036554

Millard, Judith; Appleton, Hazel; Parry, J. V.

1987-01-01

140

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

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.

NONE

1995-05-01

141

THE COLONY OVERLAY PROCEDURE FOR PEPTIDASES TO DETECT AND ENUMERATE TOTAL VIBRIONACEAE IN MOLLUSCAN SHELLFISH AND THEIR GROWING WATERS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since 1925, molluscan shellfish harvesting has been regulated in the United States based on sanitary surveys of shellfish growing waters. Surveys have relied on the use of coliform standards which have effectively eliminated outbreaks of typhoid fever and other bacterial illnesses. Only the Vibrio...

142

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

PubMed Central

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

McIntyre, Lorraine; Cassis, David; Haigh, Nicola

2013-01-01

143

New Jersey has a small but expanding shellfish aquaculture industry. Two species are grown: the hard clam Mercenaria  

E-print Network

#12;New Jersey has a small but expanding shellfish aquaculture industry. Two species are grown scale until 1997. With the State's initiation of Aquaculture Development Zones and new permitting regulations, New Jersey's shellfish aquaculture industry is poised for expansion. Documentation of the extent

Garfunkel, Eric

144

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

PubMed

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

Lee, R J; Reese, R A

2014-06-01

145

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

PubMed Central

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 ?g 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

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

146

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

PubMed

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 ?g 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

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

147

Age Determination Methods for Northwest Atlantic Species (of fish and shellfish)  

NSDL National Science Digital Library

The Fishery Biology Program of the Northeast Fisheries Science Center provides this resource to assist with age determination of fish and shellfish species from the Northwest Atlantic. Released in its current form in 1997, this resource represents the fruit of many years of accumulated expertise. Techniques for aging sixteen species of fish or shellfish are given here, based on growth marks in scales, otoliths, and shells. From Atlantic Butterfish through Yellowtail Flounder, these detailed descriptions and black-and-white images should be of valuable assistance to researchers.

Almeida, F. P.

1997-01-01

148

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

SciTech Connect

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.

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

1987-01-01

149

TRPV1 as a key determinant in ciguatera and neurotoxic shellfish poisoning  

PubMed Central

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

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

2007-01-01

150

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

PubMed Central

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 evidence that allergy to shellfish alters the risk of reaction to intravenous contrast more than any other allergy and asking about such allergies in pre-angiogram assessment will not provide any additional information except propagating the myth. PMID:24669292

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

2014-01-01

151

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

SciTech Connect

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.

Beghian, L.; Melnick, J.

1986-07-25

152

From the Tides of Puget Sound to Your Plate: Northwest Shellfish  

E-print Network

and mussels. Shellfish production requires a healthy, functioning ecosystem to provide safe water quality, Washington State's tidelands have served as productive farm beds for nutritious and delicious oysters, clams, and the ocean. Similar to agriculture, aquaculture can take place in the natural environment or in a manmade

153

Recent domoic acid closures of shellfish harvest areas in Washington State inland waterways  

E-print Network

to the indigenous tribes of the Pacific Northwest is evidenced by a phrase in the Quinault tribal language ``taRecent domoic acid closures of shellfish harvest areas in Washington State inland waterways Vera L. Borchert d , Kathi A. Lefebvre a a Marine Biotoxins Program, Environmental Conservation Division, Northwest

Cochlan, William P.

154

Rapid Detection of Noroviruses in Fecal Samples and Shellfish by Nucleic Acid Sequence-based Amplification  

Microsoft Academic Search

The purpose of this study was to determine the efficacy of a nucleic acid sequence-based amplification (NASBA) method of detecting noroviruses in artificially and naturally contaminated shellfish. We used 58 fecal samples that tested positive for noroviruses with electron microscopy (EM) to develop an NASBA assay for these viruses. Oligonucleotide primers targeting the polymerase coding region were used to amplify

Xiaoxia Kou; Qingping Wu; Jumei Zhang; Hongying Fan

2006-01-01

155

AN ECONOMIC ANALYSIS OF SHELLFISH PRODUCTION ASSOCIATED WITH THE ADOPTION OF INTEGRATED  

E-print Network

-TROPHIC AQUACULTURE IN BRITISH COLUMBIA by Patrick Kitchen Bachelor of Arts with Distinction, McGill University, 2006 PRODUCTION ASSOCIATED WITH THE ADOPTION OF INTEGRATED MULTI- TROPHIC AQUACULTURE IN BRITISH COLUMBIA Chair-Trophic Aquaculture (IMTA) combines fed aquaculture (finfish) with extractive aquaculture (shellfish and seaweeds

156

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...

157

Reevaluation of Production of Paralytic Shellfish Toxin by Bacteria Associated with Dinoflagellates of the Portuguese Coast  

Microsoft Academic Search

Paralytic shellfish toxins (PSTs) are potent neurotoxins produced by certain dinoflagellate and cyanobac- terial species. The autonomous production of PSTs by bacteria remains controversial. In this study, PST production by two bacterial strains, isolated previously from toxic dinoflagellates, was evaluated using bio- logical and analytical methods. Analyses were performed under conditions determined previously to be optimal for toxin production and

Claudia A. Martins; Paula Alvito; Maria Joao Tavares; Paulo Pereira; Gregory Doucette; Susana Franca

2003-01-01

158

artha's Vineyard Shellfish Group is a public nonprofit located on Martha's Vineyard Island  

E-print Network

and cultured first at the Group's shellfish hatchery (where they also grow algae as feed, a convener, cultivator and champion of sustainability on campus, in the state and region, and around, mostly flowing out of septic systems. This can cause eutrophication, a process that creates acidic

New Hampshire, University of

159

Toxic effects, pharmacokinetics and clearance of saxitoxin, a component of paralytic shellfish poison (PSP), in cats  

Microsoft Academic Search

Saxitoxin (STX) was the first known and most studied toxic component of paralytic shellfish poisoning (PSP). This toxin blocks neuronal transmission by binding to the voltage-gated Na+ channel. Although the toxin's mechanism of action is well known at the molecular level, there are still many unresolved questions about its pharmacokinetics and the PSP intoxication syndrome in mammals. Some of these

Dar??o Andrinolo; Luis F Michea; Néstor Lagos

1999-01-01

160

Sheep mortality associated with paralytic shellfish poisons from the cyanobacterium Anabaena circinalis  

Microsoft Academic Search

This is the first report of sheep mortalities associated with paralytic shellfish poisons (PSPs) from the cyanobacterium Anabaena circinalis Rabenhorst. Fourteen sheep died within 150 m of a farm dam containing a dense bloom of A. circinalis. Extracts from both the cyanobacterium and small intestine from a dead ewe were analysed by high-performance liquid chromatography (HPLC) and found to contain

Andrew P Negri; Gary J Jones; Michael Hindmarsh

1995-01-01

161

IDENTIFYING CLIMATIC FACTORS INFLUENCING COMMERCIAL FISH AND SHELLFISH LANDINGS IN MARYLAND!  

E-print Network

IDENTIFYING CLIMATIC FACTORS INFLUENCING COMMERCIAL FISH AND SHELLFISH LANDINGS IN MARYLAND! ROBERT. KEVIN SUMMERS6 ABSTRACT In five of the seven most important commercial fisheries of Maryland of the University of Maryland. "University of Maryland, Chesapeake Biological Labora- tory, Solomons, MD 20688. s

162

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...

163

Archaeofauna 17 (2008): 63-76 Intertidal shellfish use during the Middle  

E-print Network

of South Africa TERESA E. STEELE1 & RICHARD G. KLEIN2 1 Department of Anthropology, University,000 years ago to historic times) archaeological sites along the coast of South Africa frequently preserve they lived at lower population densities. KEYWORDS: MOLLUSKS, SHELLFISH, LIMPETS, SOUTH AFRICA, MIDDLE STONE

2008-01-01

164

Biological effects of shellfish harvesting on oyster reefs: resolving a fishery conflict by  

E-print Network

harvesting was conducted over a one-year period by a professional shellfisherman who used realistic fish- ing86 Biological effects of shellfish harvesting on oyster reefs: resolving a fishery conflict, California 93101 Manuscript accepted 24 March 1999. Fish. Bull. 98:86­95 (2000). Abstract.­We conducted

165

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

E-print Network

association between Alexandrium abundance and shell- fish toxicity. One possibility is that toxic cells with toxin levels approaching or exceeding 80 g toxin/100 g shellfish tissue are closed to harvesting, often resulting in significant economic losses. The summer of 2005 was especially severe, resulting in harvesting

Thomas, Andrew

166

MERCURY IN FISH AND SHELLFISH OF THE NORTHEAST PACIFIC. II. SABLEFISH, ANOPLOPOMA FIMBRIA  

E-print Network

MERCURY IN FISH AND SHELLFISH OF THE NORTHEAST PACIFIC. II. SABLEFISH, ANOPLOPOMA FIMBRIA ALICE S several locations in Alaska, Washington, Oregon, and California were analyzed for their mercury content. Mean mercury level in this species varied with the geographical location of catch, showing a gradual

167

SHELLFISH AQUACULTURE SUITABILITY WITHIN BAYLOR GROUNDS OF THE LOWER RAPPAHANNOCK RIVER  

E-print Network

SHELLFISH AQUACULTURE SUITABILITY WITHIN BAYLOR GROUNDS OF THE LOWER RAPPAHANNOCK RIVER FINAL of the aquaculture industry to public Baylor ground, timely information regarding the productivity of these grounds and the ability to support aquaculture would be highly desirable information. In this scenario, public bottom

168

Species Diversity in Florida's Shellfish Aquaculture Industry Over the past several years there has been an  

E-print Network

Species Diversity in Florida's Shellfish Aquaculture Industry Over the past several years there has and market potential. Currently, the sunray venus is being investigated as a new aquaculture species to Florida of the green mussel, which is an important fishery and aquaculture species in the Indo

Florida, University of

169

Occurrence of polybrominated diphenyl ethers in fish and shellfish downstream from electronic-waste recycling plants.  

PubMed

We measured 39 polybrominated diphenyl ethers (PBDEs) in the muscle tissue of three species of fish (Sciaenops ocellatus, Sparus macrocephalus, and Lateolabraxjaponicus) and four species of shellfish (Tegillarca granosa, Cyclina sinensis, Sinonovacula constricta, and Ostrea cucullata) that were collected downstream of electronic-waste recycling plants in Taizhou, China. A total of 24 PBDE congeners (PBDE24) in the samples were detected. The sigma PBDE24 (total PBDE) ranged from 545.4 to 1688.7 ng/kg ww (wet weight). The mean sigma PBDE24 concentration was 1382.6 ng/kg ww in fish and 858.1 ng/kg ww in shellfish. The lower brominated congeners were detected at relatively high concentrations in all species. The penta-products, produced from e-waste, were found at relatively low levels. A principal component analysis suggested a significant correlation among di-, tri-, tetra-, and hepta-BDEs for the three species of fish. Similarly, we found a significant correlation between mono- and tri-BDEs in the shellfish. Our results suggested that the processes of PBDE metabolism and elimination were similar in both fish and shellfish. In addition, the primary source of PBDEs appeared to be from the debromination of high brominated PBDEs. PMID:20608509

Jiang, Jinhua; Shi, Shidi; Chen, Tao

2010-01-01

170

Risk assessment of heavy metals in shellfish for the population in Nha Trang City, Vietnam.  

PubMed

The study described in this article was designed to estimate the dietary intake of lead, cadmium, and mercury due to the shellfish consumption of the population in Nha Trang City, Vietnam. The lead, cadmium, and mercury concentrations in the shellfish consumed popularly by the Nha Trang population were investigated by inductively coupled plasma-mass spectrometry from May 2008 to January 2009. The lead, cadmium, and mercury concentration ranges in shellfish are equal to 0.008-0.083, 0.013-0.056, and 0.028-0.056 mg/kg, respectively. The dietary intake of these elements was determined by a total diet study. The heavy metals intake was estimated for six subpopulation groups: men and women aged 18-29, 30-54, and > or =55. The dietary intakes of lead, cadmium, and mercury by the Nha Trang population are currently well below the provisional tolerable weekly intakes of lead, cadmium, and mercury, respectively. Therefore, no risk exists concerning the levels of exposure of Nha Trang consumers to the contaminants studied due to shellfish consumption. PMID:24645414

Nguyen, Thuan Anh; Roudot, Alain-Claude; Massin, Dominique Parent

2014-01-01

171

Comparative study on paralytic shellfish toxin profiles of the dinoflagellate Gymnodinium catenatum from three different countries  

Microsoft Academic Search

Paralytic shellfish toxin profiles of the dinoflagellate Gymnodinium catenatum Graham were investigated as a possible biochemical marker to distinguish different geographic populations of this species. Isolates obtained between 1986 and 1988 from Japan, Tasmania (Australia) and Galicia (Spain) were cultured under similar conditions and the toxins produced were analyzed using HPLC. Variations in temperature, salinity, and nitrate and phosphate levels

Y. Oshima; S. I. Blackburn; G. M. Hallegraeff

1993-01-01

172

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...

173

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...

174

MOLECULAR DETECTION AND HIGH PRESSURE SANITIZATION OF SHELLFISH-BORNE VIRUSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A highly sensitive virus RNA extraction method for shellfish, using Glycine buffer, Polyethylene glycol, Tri-reagent and poly dT magnetic beads, termed the GPTT procedure, has recently been developed which facilitates RT-PCR detection of hepatitis A (HAV), hepatitis E (HEV), and Norwalk-like viruses...

175

Phycotoxin?related shellfish poisoning: Bivalve molluscs are not the only vectors  

Microsoft Academic Search

The continuing increase in numbers of toxic algal species coupled with increased incidences of blooms of these species presents a constant threat to public health worldwide. Traditionally, only filter?feeding molluscs that concentrate these toxic algae are considered in monitoring programs for paralytic (PSP), diarrhetic (DSP), neurotoxic (NSP), and amnesic (ASP) shellfish poisons; however, increasing attention is being paid to higher?order

Sandra E. Shumway

1995-01-01

176

Paralytic Shellfish Toxins in Bivalve Molluscs: Occurrence, Transfer Kinetics, and Biotransformation  

Microsoft Academic Search

This is a critical review of the global distribution, sources of variation in toxicity, anatomical partitioning, metabolism, and detoxification kinetics of paralytic shellfish poisoning (PSP) toxins (carbamate, TV-sulfocarbamoyl, and decarbamoyl saxitoxin derivatives) in bivalve molluscs. Marked interspecific differences in toxin accumulation are related to differences in toxin sensitivity, determined from neurological, physiological, and behavioral responses. Toxicity also varies considerably with

V. Monica Bricelj; Sandra E. Shumway

1998-01-01

177

Trophic transfer of paralytic shellfish toxins from clams (Ruditapes philippinarum) to gastropods  

E-print Network

Trophic transfer of paralytic shellfish toxins from clams (Ruditapes philippinarum) to gastropods Alexandrium tamarense (ATCI01), which predominantly produces C2 toxin, was fed to the clams (Ruditapes clams were deter- mined by High Performance Liquid Chromatographic (HPLC) analyses, and the clams were

Yu, K.N.

178

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

PubMed

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

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

2015-02-15

179

Fate of benzoate paralytic shellfish poisoning toxins from Gymnodinium catenatum in shellfish and fish detected by pre-column oxidation and liquid chromatography with fluorescence detection.  

PubMed

Several cultured strains of Gymnodinium catenatum isolated worldwide have been shown to produce important proportions of the recently discovered benzoate paralytic shellfish poisoning (PSP) toxins GC1 through GC3. These toxins pose a new challenge for the HPLC analysis of shellfish predating during blooms of this microalga because due to their hydrophobicity are retained along the C18 solid-phase extraction step employed to eliminate interferences. The production of GC toxins was confirmed in a clone of G.catenatum isolated from the Portuguese Northwest coast during the winter bloom of 2005, in addition to a clone from 1989 reported previously by other authors. The major peroxide oxidation products of GC1+2 and GC3 were, respectively, dcGTX2+3 and dcSTX. The search of benzoate analogues in bivalves contaminated during the winter 2005 bloom showed these analogues constituted a minor component of the N(1)-H containing toxins, as selectively detected by peroxide oxidation. While in G.catenatum GC1-3 were the major components after C1+2 and B1, in bivalves dcGTX2+3 and dcSTX were the major components after C1+2 and B1. Similar conclusions were later extended to more shellfish species naturally contaminated during the autumn bloom of 2007. In the gut content of sardines GC toxins were present, while in crabs predating upon shellfish, these were absent. A generalised conversion of GC toxins into decarbamoyl analogues was confirmed by in vitro incubations of bivalve's digestive glands with semi-purified GC toxins. This is the first report of widespread carbamoylase activity in shellfish, exclusively targeted at benzoate PSP analogues and that is heat-inactivated. Despite the high proportion of benzoate analogues produced by G.catenatum, analyses of bivalves contaminated with PSP toxins seem to be simplified due to the important conversion of benzoate into decarbamoyl analogues that occurs in bivalves. These last analogues are detected by common HPLC methods used for food protection. PMID:18371975

Vale, Paulo

2008-05-01

180

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

PubMed

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 ?-hexachlorocyclohexane (?-HCH) (2.3-4.9 ng/g fat) were all higher than the concentrations of other HCH isomers, ?-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

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

2015-02-01

181

Concentrations and distribution of organochlorine pesticides in shellfish from Changjiang estuary  

NASA Astrophysics Data System (ADS)

To analyze and evaluate the status of organochlorine pollutants in the Changjiang (Yangtze River) estuary and adjacent waters, the concentrations of hexachlorocyclohexane (HCHs) and dichlorodiphenyltrichloroethane (DDTs) in shellfish collected in study area from 2006 to 2007 were determined with gas chromatography (GC). The concentration range of HCHs was (ND-12.13)×10-3 mg/kg wet weight and averaged at 0.54×10-3 mg/kg while the concentration of DDTs was in the range of (4.06-281.73) ×10-3 mg/kg with a mean of 57.52×10-3 mg/kg in the survey areas. The concentrations of DDTs in the shellfish were higher than HCHs’, so that DDTs could be considered as typical organochlorine pollutants in the areas. The concentrations of DDTs in the shellfish were higher than HCHs’, so that DDTs could be considered as typical organochlorines pollutants. The HCHs in all the shellfish conformed to the first level of criterion (0.02 mg/kg) of the Marion Biology Quality (GB 18421-2001), and that of DDTs in most samples were beyond the first level (0.01 mg/kg) but conformed to the second level (0.10 mg/kg). On average, ?-HCH and ?-HCH occupied the most part of HCHs, while O,P’-DDT and P,P’-DDT occupied the most part of DDTs. The concentrations of organocholorine pesticides in shellfish samples varied in site and in species. The highest level occurred at the Shengsi (SS), followed by Yangkougang (YKG), Lvsi (LS), Dongyuan (DY) and Beibayao (BBY), low concentrations were observed at Changsha (CS), Beidaodi (BDD), and Gouqi (GQ). The concentration of HCHs and DDTs in most sites decreased clearly from 2006 to 2007 except for YKG, DY, BDD, LYS, and SS. All of above results suggested that the study area was slightly affected by organochlorine pesticide, special by DDTs.

Ma, Jizhen; Shen, Xinqiang; Yuan, Qi; Jiang, Mei

2008-11-01

182

[Poisoning by the consumption of shellfish contaminated with paralytic venom in the XII Region, Chile. Anatomopathological study].  

PubMed

The necropsy findings of ten subjects died as a consequence of paralytic shellfish intoxication are presented. These deaths occurred between march 1991 and january 1992, affected to seamen and occurred within 72 hours of contaminated shellfish ingestion. Necropsies were performed within 24 hours of death. The most outstanding necropsy findings were the presence of pink lividities, mydriasis and isocoria, airway obstruction with gastric contents, severe brain, lung liver and spleen swelling and edema, and digestive and respiratory mucosal congestion and friability. The toxicological study of urine, gastric content and organ samples revealed the presence of shellfish paralytic poison. PMID:8235174

Montebruno, D

1993-01-01

183

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 ...

184

ACUTE TOXICITY, SUBLETHAL EFFECTS AND BIOCONCENTRATION OF CHLORINATION PRODUCTS, VIRUSES, AND BACTERIA IN EDIBLE SHELLFISH: A REVIEW  

EPA Science Inventory

The report identifies, synthesizes, and summarizes published scientific data concerning toxicity, sublethal physiological effects, and uptake/depuration rates of chlorine, viruses, and bacteria in edible marine shellfish of the United States. The summary may provide environmental...

185

Levels and distribution of polybrominated diphenyl ethers in plant, shellfish and sediment samples from Laizhou Bay in China  

Microsoft Academic Search

Polybrominated diphenyl ethers (PBDEs) are potentially harmful and persistent environmental pollutants. PBDEs concentrations are reported in plant, shellfish and sediment samples collected from Chinese Laizhou Bay. The ?11PBDE concentrations in plant and shellfish samples from Laizhou Bay were in the range of 70–5900ngg?1 and 230–720ngg?1 lipid, respectively. The ?11PBDEs concentrations in river sediment intervals samples ranged from 1.3 to 1800ng

Jun Jin; Weizhi Liu; Ying Wang; Xiao Yan Tang

2008-01-01

186

Heavy metals in raw, fried and grilled Mediterranean finfish and shellfish.  

PubMed

The effect of domestic pan-frying and grilling on Cd, Cr, Cu, Fe, Hg, Ni, Pb and Zn content of popular small Mediterranean finfish and shellfish was studied. The species selected -namely anchovy, bogue, hake, picarel, sardine, sand smelt, stripped mullet, Mediterranean mussel, shrimp and squid- are among the most commonly marketed and consumed in Greece and most of the Mediterranean countries. Both culinary practices examined resulted in increased metals concentrations compared to those of raw samples, the increment being inversely related to fish size and -in most cases- being more extended in pan-frying. The consumption of cooked seafood is expected to provide significant amounts of Fe and Zn followed, in decreasing order, by Cr, Cu and Ni. In addition, the estimation of (a) weekly intakes and (b) target hazard quotients for the toxic elements Cd, Hg and Pb revealed that the cooked fish and shellfish do not pose any health risk for the consumers. PMID:22813872

Kalogeropoulos, Nick; Karavoltsos, Sotirios; Sakellari, Aikaterini; Avramidou, Stella; Dassenakis, Manos; Scoullos, Michael

2012-10-01

187

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

PubMed

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. PMID:25098307

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

2014-10-01

188

Molecular Characterization of Hepatitis A Virus Isolates from a Transcontinental Shellfish-Borne Outbreak  

PubMed Central

One hundred eighty-four serologically confirmed cases of hepatitis A were reported in eastern Spain in 1999. A matched case-control study implicated imported coquina clams complying with European Union shellfish standards as the source of infection; this implication was confirmed by the detection by reverse transcription-PCR of hepatitis A virus (HAV) RNA in shellfish samples. In spite of the recognized low variability of HAV, genetic characterization of the complete capsid region of virus isolates from patient serum samples revealed the existence of both synonymous and nonsynonymous variants. Two antigenic variants were detected, one in a discontinuous epitope defined by monoclonal antibody K3-4C8 and a second in a linear VP1 epitope of the virus. In spite of these antigenic variants, all isolates were assigned to genotype IB, providing further evidence that the outbreak originated from a common source, although multiple strains were likely to be involved. PMID:12409389

Sánchez, Glòria; Pintó, Rosa M.; Vanaclocha, Hermelinda; Bosch, Albert

2002-01-01

189

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

NASA Astrophysics Data System (ADS)

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 ?g/kg weight, equivalent to 20 ng/mL), low maintenance, and rapid (less than 60 min).

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

2012-09-01

190

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

USGS Publications Warehouse

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.

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

2014-01-01

191

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

Microsoft Academic Search

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

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

2012-01-01

192

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

Microsoft Academic Search

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

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

2011-01-01

193

Thermal degradation of paralytic shellfish poisoning toxins in scallop digestive glands  

Microsoft Academic Search

Digestive glands containing paralytic shellfish poisoning (PSP) toxins were isolated from toxic scallops. Citrate\\/phosphate buffers with the pH values ranging from 3 to 7 were added to achieve predetermined pH levels. The samples were heated at 90, 100, 110, 120 and 130°C using a computer controlled oil bath, and three tubes at each pH level were transferred into an ice

W. M Indrasena; T. A Gill

1999-01-01

194

Reevaluation of production of paralytic shellfish toxin by bacteria associated with dinoflagellates of the Portuguese coast.  

PubMed

Paralytic shellfish toxins (PSTs) are potent neurotoxins produced by certain dinoflagellate and cyanobacterial species. The autonomous production of PSTs by bacteria remains controversial. In this study, PST production by two bacterial strains, isolated previously from toxic dinoflagellates, was evaluated using biological and analytical methods. Analyses were performed under conditions determined previously to be optimal for toxin production and detection. Our data are inconsistent with autonomous bacterial PST production under these conditions, thereby challenging previous findings for the same strains. PMID:12957964

Martins, Claudia A; Alvito, Paula; Tavares, Maria João; Pereira, Paulo; Doucette, Gregory; Franca, Susana

2003-09-01

195

Real-time RT-PCR for norovirus screening in shellfish  

Microsoft Academic Search

Real-time RT-PCR, combining amplification and detection of virus-specific amplicons, is a promising tool for norovirus detection in environmental or food samples such as shellfish. We developed a real-time RT-PCR assay based on one-step detection using single primer sets and probes for norovirus genogroups I and II. Seventy and seven RT-PCR units of genogroup I and II reference norovirus strains, respectively,

F. Loisy; R. L. Atmar; P. Guillon; P. Le Cann; M. Pommepuy; F. S. Le Guyader

2005-01-01

196

Detection of pathogenic Vibrio spp. in shellfish by using multiplex PCR and DNA microarrays.  

PubMed

This study describes the development of a gene-specific DNA microarray coupled with multiplex PCR for the comprehensive detection of pathogenic vibrios that are natural inhabitants of warm coastal waters and shellfish. Multiplex PCR with vvh and viuB for Vibrio vulnificus, with ompU, toxR, tcpI, and hlyA for V. cholerae, and with tlh, tdh, trh, and open reading frame 8 for V. parahaemolyticus helped to ensure that total and pathogenic strains, including subtypes of the three Vibrio spp., could be detected and discriminated. For DNA microarrays, oligonucleotide probes for these targeted genes were deposited onto epoxysilane-derivatized, 12-well, Teflon-masked slides by using a MicroGrid II arrayer. Amplified PCR products were hybridized to arrays at 50 degrees C and detected by using tyramide signal amplification with Alexa Fluor 546 fluorescent dye. Slides were imaged by using an arrayWoRx scanner. The detection sensitivity for pure cultures without enrichment was 10(2) to 10(3) CFU/ml, and the specificity was 100%. However, 5 h of sample enrichment followed by DNA extraction with Instagene matrix and multiplex PCR with microarray hybridization resulted in the detection of 1 CFU in 1 g of oyster tissue homogenate. Thus, enrichment of the bacterial pathogens permitted higher sensitivity in compliance with the Interstate Shellfish Sanitation Conference guideline. Application of the DNA microarray methodology to natural oysters revealed the presence of V. vulnificus (100%) and V. parahaemolyticus (83%). However, V. cholerae was not detected in natural oysters. An assay involving a combination of multiplex PCR and DNA microarray hybridization would help to ensure rapid and accurate detection of pathogenic vibrios in shellfish, thereby improving the microbiological safety of shellfish for consumers. PMID:15574946

Panicker, Gitika; Call, Douglas R; Krug, Melissa J; Bej, Asim K

2004-12-01

197

Detection of Norwalk Virus and Hepatitis A Virus in Shellfish Tissues with the PCR  

Microsoft Academic Search

A method for the detection of Norwalk virus and hepatitis A virus from shellfish tissues by PCR was developed. Virus was added to the stomach and hepatopancreatic tissues of oysters or hard-shell clams, and viralnucleicacidswerepurifiedbyamodificationofapreviouslydescribedmethod(R.L.Atmar,T.G.Metcalf, F. H. Neill, and M. K. Estes, Appl. Environ. Microbiol. 59:631-635, 1993). The new method had the following advantages compared with the previously described method:

ROBERT L. ATMAR; FREDERICK H. NEILL; JESUS L. ROMALDE; FRANCOISE LE GUYADER; CHERYL M. WOODLEY; THEODORE G. METCALF; ANDMARY K. ESTES

1995-01-01

198

Sediment bacterial indicators in an urban shellfishing subestuary of the lower Chesapeake Bay.  

PubMed Central

The objectives of this study were to document the spatial and temporal distributions and compositions of bacteria in the sediments and overlying waters of an important urban shellfishing area in the lower Chesapeake Bay region, the Lynnhaven Estuary. Marked fluctuations were observed in the date of many of the physicochemical parameters and the indicator bacteria. The higher-salinity water and coarser sediment of the inlet site showed lower overall bacterial densities than did the headwater sites, where freshwater runoff and decreased tidal action were characteristic. Densities of benthic indicator bacteria, when expressed on a volumetric basis, were significantly greater than counts in the overlying waters. These counts were indicative of a fecally polluted system and were well above the safe maximum limits for shellfish-growing waters. Significantly fewer total and fecal bacteria were observed in both the water and the sediment during the warm months of May, July, and August. The primary sources of the Lynnhaven's bacterial pollution appeared to be typical of urban and agricultural runoff, although failure of septic tank systems was suspected as a problem in the Lynnhaven's western branch. These results illustrated that sediments in shellfishing areas could serve as a reservoir for high densities of indicator bacteria and that, potentially, pathogens could pose a health hazard. PMID:7294785

Erkenbrecher, C W

1981-01-01

199

Open-sandwich immunoassay for sensitive and broad-range detection of a shellfish toxin gonyautoxin.  

PubMed

At present, the analytical method for paralytic shellfish poisoning (PSP) toxins in shellfish is the mouse bioassay (MBA), which is an official method of the Association of Analytical Communities (AOAC [8]). However, the low sensitivity and concerns over the number of live animals required for testing have been cited as the major reason for seeking its replacement. In this report, we employed an open-sandwich immunoassay (OS-IA) to detect gonyautoxin (GTX2/3), a kind of PSP toxins. OS-IA, which utilizes the antigen-induced enhancement of antibody VH/VL interaction, can measure a small molecule antigen in a noncompetitive format. Hence it has a wider working range and shorter measurement time. We isolated anti-GTX2/3 antibody gene from a hybridoma GT-13A by screening a Fab-displaying phage library. Then the vectors for OS-IA were constructed, and examined for antigen concentration-dependency of the VH/VL interaction by OS-ELISA. As a result, in each case, signal intensity increases notably in a wide concentration range (0.1 to >1000 ng mL(-1)) of free GTX2/3, which was enough to cover its regulation value (80 ?g 100 g(-1)) in many countries. So OS-IA will be widely applicable to detect PSP toxins in shellfish meats and in drinking water. PMID:23953213

Hara, Yuko; Dong, Jinhua; Ueda, Hiroshi

2013-09-01

200

Quantitative ELISA kit for paralytic shellfish toxins coupled with sample pretreatment.  

PubMed

A new ELISA kit to quantitate the level of paralytic shellfish poisoning (PSP) toxins in crude shellfish extracts was developed. A conjugate for preparing antigen and a novel antibody used in the ELISA was prepared based on the unique reactions between C11-O-sulfate toxins such as gonyautoxins 2 and 3 (GTX2,3) and various thiol compounds, followed by coupling to keyhole limpet hemocyanin. The compounds necessary for competitive ELISA, labeled toxin and an artificial standard toxin to replace saxitoxin in the analysis, were also produced by the same techniques. The resulting ELISA recognized all the toxin components tested; however, carbamoyl-N-sulfate derivatives such as B and C toxins and N1-OH toxins such as neoSTX and GTX1,4 showed low affinity to the antibody. The difference in the reactivity of the antibody observed among the toxin components prevents accurate quantification of the toxin amounts in shellfish extracts. To address this problem, the former toxin components were transformed to corresponding carbamate toxins by mild HCl treatment according to a conventional method. The reduction of N1-OH of the latter toxins to N1-H was performed by our original method using hemin as a catalyst. We report here the new ELISA kit coupled with the pretreatment process to transform the toxin components favorable for the quantitative analysis of PSP toxins. PMID:24830145

Sato, Shigeru; Takata, Yoshinobu; Kondo, Sunaho; Kotoda, Akiko; Hongo, Naoto; Kodama, Masaaki

2014-01-01

201

Benefits to shorebirds from invasion of a non-native shellfish.  

PubMed

Introductions of non-native species are seen as major threats to ecosystem function and biodiversity. However, invasions of aquatic habitats by non-native species are known to benefit generalist consumers that exhibit dietary switches and prey upon the exotic species in addition to or in preference to native ones. There is, however, little knowledge concerning the population-level implications of such dietary changes. Here, we show that the introduction of the Manila clam Tapes philippinarum into European coastal waters has presented the Eurasian oystercatcher Haematopus ostralegus ostralegus with a new food resource and resulted in a previously unknown predator-prey interaction between these species. We demonstrate, with an individuals-based simulation model, that the presence of this non-native shellfish, even at the current low density, has reduced the predicted over-winter mortality of oystercatchers at one recently invaded site. Further increases in clam population density are predicted to have even more pronounced effects on the density dependence of oystercatcher over-winter mortality. These results suggest that if the Manila clam were to spread around European coastal waters, a process which is likely to be facilitated by global warming, this could have considerable benefits for many shellfish-eating shorebird populations. PMID:17412684

Caldow, Richard W G; Stillman, Richard A; dit Durell, Sarah E A le V; West, Andy D; McGrorty, Selwyn; Goss-Custard, John D; Wood, Philippa J; Humphreys, John

2007-06-01

202

Sediment bacterial indicators in an urban shellfishing subestuary of the lower Chesapeake Bay.  

PubMed

The objectives of this study were to document the spatial and temporal distributions and compositions of bacteria in the sediments and overlying waters of an important urban shellfishing area in the lower Chesapeake Bay region, the Lynnhaven Estuary. Marked fluctuations were observed in the date of many of the physicochemical parameters and the indicator bacteria. The higher-salinity water and coarser sediment of the inlet site showed lower overall bacterial densities than did the headwater sites, where freshwater runoff and decreased tidal action were characteristic. Densities of benthic indicator bacteria, when expressed on a volumetric basis, were significantly greater than counts in the overlying waters. These counts were indicative of a fecally polluted system and were well above the safe maximum limits for shellfish-growing waters. Significantly fewer total and fecal bacteria were observed in both the water and the sediment during the warm months of May, July, and August. The primary sources of the Lynnhaven's bacterial pollution appeared to be typical of urban and agricultural runoff, although failure of septic tank systems was suspected as a problem in the Lynnhaven's western branch. These results illustrated that sediments in shellfishing areas could serve as a reservoir for high densities of indicator bacteria and that, potentially, pathogens could pose a health hazard. PMID:7294785

Erkenbrecher, C W

1981-09-01

203

Detection of Norwalk virus and hepatitis A virus in shellfish tissues with the PCR.  

PubMed

A method for the detection of Norwalk virus and hepatitis A virus from shellfish tissues by PCR was developed. Virus was added to the stomach and hepatopancreatic tissues of oysters or hard-shell clams, and viral nucleic acids were purified by a modification of a previously described method (R.L. Atmar, T.G. Metcalf, F.H. Neill, and M.K. Estes, Appl. Environ. Microbiol. 59:631-635, 1993). The new method had the following advantages compared with the previously described method: (i) more rapid sample processing; (ii) increased test sensitivity; (iii) decreased sample-associated interference with reverse transcription-PCR; and (iv) use of chloroform-butanol in place of the chlorofluorocarbon trichlorotrifluoroethane. In addition, internal standards for both Norwalk virus and hepatitis A virus were made which demonstrated when inhibitors to reverse transcription-PCR were present and allowed quantitation of the viral nucleic acids present in samples. This assay can be used to investigate shellfish-associated gastroenteritis outbreaks and to study factors involved in virus persistence in shellfish. PMID:7487032

Atmar, R L; Neill, F H; Romalde, J L; Le Guyader, F; Woodley, C M; Metcalf, T G; Estes, M K

1995-08-01

204

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

PubMed

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 ?p.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, lindane, triazines, PBDE, and chlorinated paraffins.In France, the results of contaminant monitoring have indicated that Cd, but not lead (< 0.26 mg kg-1) or mercury (< 0.003 mg kg-1), has had some non-compliances. Detections for PCBs and dioxins in shellfish were far below the regulatory thresholds in oysters (< 0.6 pg g-l), mussels (< 0.6 pg g-1), and king scallops (< 0.4 pg g-1). The benzo[a]pyrene concentration in marketed mussels and farmed shellfish does not exceed the regulatory threshold. Some monitoring data are available on shellfish flesh contamination for unregulated organic contaminants.Of about 100 existing organo stannic compounds, residues of the mono-, di-, and tributyltin (MBT, DBT, and TBT) and mono-, di-, and triphenyltin (MPT, DPT,and TPT) compounds are the most frequently detected in fishery products. Octyltins are not found in fishery products. Some bivalve mollusks show arsenic levels up to 15.8 mg kg-1. It seems that the levels of arsenic in the environment derive less from bioaccumulation, than from whether the arsenic is in an organic or an inorganic form. In regard to the other metals, levels of zinc and magnesium are higher in oysters than in mussels.To protect shellfish from chemical contamination, programs have been established to monitor water masses along coastal areas. The French monitoring network(ROCCH) focuses on environmental matrices that accumulate contaminants. These include both biota and sediment. Example contaminants were studied in a French coastal lagoon (Arcachon Bay) and in an estuary (Bay of Seine), and these were used to illustrate the usefulness of the monitoring programs. Twenty-one pesticidal and biocidal active substances were detected in the waters of Arcachon Bay during the summers from 1999 to 2003, at concentrations ranging from a few nanograms per liter to several hundred nanograms per liter. Most of the detected substances were herbicides, including some that are now banned. Organotin compounds have been detected in similarly semi-enclosed waters elsewhere (bays, estuaries, and ha

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

2011-01-01

205

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

PubMed Central

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

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

2004-01-01

206

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...

207

Supplemental Feeding of Clam Seed in Land-based Nurseries Shellfish Algae Diet is a commercially available, super-concentrated mix of four marine micro-  

E-print Network

Supplemental Feeding of Clam Seed in Land-based Nurseries Shellfish Algae Diet is a commercially available, super-concentrated mix of four marine micro- algae that provide a nutritional profile for shellfish. Although the algal cells are intact, the algae are not alive. The diet does not contain

Florida, University of

208

FishMicrosat: a microsatellite database of commercially important fishes and shellfishes of the Indian subcontinent  

PubMed Central

Background Microsatellite DNA is one of many powerful genetic markers used for the construction of genetic linkage maps and the study of population genetics. The biological databases in public domain hold vast numbers of microsatellite sequences for many organisms including fishes. The microsatellite data available in these data sources were extracted and managed into a database that facilitates sequences analysis and browsing relevant information. The system also helps to design primer sequences for flanking regions of repeat loci for PCR identification of polymorphism within populations. Description FishMicrosat is a database of microsatellite sequences of fishes and shellfishes that includes important aquaculture species such as Lates calcarifer, Ctenopharyngodon idella, Hypophthalmichthys molitrix, Penaeus monodon, Labeo rohita, Oreochromis niloticus, Fenneropenaeus indicus and Macrobrachium rosenbergii. The database contains 4398 microsatellite sequences of 41 species belonging to 15 families from the Indian subcontinent. GenBank of NCBI was used as a prime data source for developing the database. The database presents information about simple and compound microsatellites, their clusters and locus orientation within sequences. The database has been integrated with different tools in a web interface such as primer designing, locus finding, mapping repeats, detecting similarities among sequences across species, and searching using motifs and keywords. In addition, the database has the ability to browse information on the top 10 families and the top 10 species, through record overview. Conclusions FishMicrosat database is a useful resource for fish and shellfish microsatellite analyses and locus identification across species, which has important applications in population genetics, evolutionary studies and genetic relatedness among species. The database can be expanded further to include the microsatellite data of fishes and shellfishes from other regions and available information on genome sequencing project of species of aquaculture importance. PMID:24047532

2013-01-01

209

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

PubMed

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

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

2002-06-01

210

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

PubMed

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

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

2014-01-01

211

1,3,5-trichloro-2-(4-nitrophenoxy)benzene (CNP) in water, sediments, and shellfish of the Ishikari River  

SciTech Connect

Since organochlorine compounds are known to be accumulated in benthic animals and CNP is very persistent in aquatic animals, shellfish might be useful as an indicator of environmental contamination by CNP. In order to understand the correlations between the concentrations in shellfish, water and sediments, it is necessary to investigate their temporal changes and the residue half-life time of CNP in the environment. For this purpose, CNP-free shellfish (Corbicula japonica) were transferred to fixed point in the lower reaches of the Ishikari River, and the CNP concentrations in shellfish, water and sediments, before and after CNP application, were examined biweekly from May to August and monthly from September to December 1984. The present paper will show that shellfish can be a biological indicator for CNP contamination in the river.

Not Available

1986-09-01

212

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

NASA Astrophysics Data System (ADS)

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 mini?m 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 using the mouse bioassay (MBA) prior to its introduction into commerce. This paper presents data from the pilot study, with primary focus on the advantages and challenges of the field kits employed onboard compared to the dockside MBA, which has served as the longstanding regulatory method for PSP toxins. In 2010 alone, the successful pilot study resulted in the safe harvest of over 2.7 million worth of surfclams in an area that has otherwise been unavailable for decades. Due to the success of this pilot study, the Protocol was adopted into the National Shellfish Sanitation Program Model Ordinance as an approved marine biotoxin control strategy for use in federal waters at the 2011 ISSC Biennial Meeting. In January 2013 a portion of Georges Bank was reopened for the harvest of Atlantic surfclams and ocean quahogs to fishermen following the Protocol.

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

213

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

PubMed

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

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

2012-01-01

214

Adenovirus detection in shellfish and urban sewage in Morocco (Casablanca region) by the polymerase chain reaction.  

PubMed

Human enteric viruses are largely excreted in faeces. These resistance of these viruses in the environment makes their faecal-oral transmission easier. Filter feeder organisms such as the mussels are bio-accumulators of viruses contaminating their aquatic environment. Thus, undercooked shellfish consumption involves sanitary risks. Thirty samples of mussels (Mytilus sp.), were tested, half were from an aquaculture origin, the others were from an area more exposed to faecal pollution. Fifteen sewage samples from this last area were also examined. Viruses were extracted from the digestive tissue by direct elution method in a glycine/NaCl pH 9.5 buffer followed by PEG 8000 precipitation. The PEG pellets were used for DNA extraction by proteinase K and phenol/chloroform. The molecular characterization, by PCR using specific adenovirus primers revealed that shellfish growing on Mohammedia (a town in the Casablanca outskirts) littoral are contaminated whereas those chosen from aquaculture and bought in the central market were not contaminated. PMID:15847929

Karamoko, Y; Ibenyassine, K; Aitmhand, R; Idaomar, M; Ennaji, M M

2005-06-01

215

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

PubMed Central

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

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

2014-01-01

216

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

SciTech Connect

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.

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

1992-07-01

217

Effect of cooking on the concentration of toxins associated with paralytic shellfish poison in lobster hepatopancreas.  

PubMed

The hepatopancreases from lobsters (Homarus americanus) obtained from two locations in eastern Canada (Gaspé and Bay of Fundy) were analysed for paralytic shellfish poisons (PSP) before and after the shellfish were cooked by boiling or steaming. Forty-five lobsters from each location were divided into three groups of 15. Two of the groups were boiled or steamed while the third was uncooked for comparison purposes. The hepatopancreases of all lobsters were individually analysed for total PSP toxicity using the standard mouse bioassay procedure. Individual toxins were determined in each sample using a high-performance liquid chromatographic procedure employing pre-chromatographic oxidation of the toxins to form fluorescent derivatives. The results demonstrated that boiling or steaming reduced total toxicity (measured as saxitoxin equivalents per hepatopancreas) by approximately 65% compared to values obtained from raw lobsters. Of the individual toxins studied, saxitoxin decreased by about 60% with both the cooking treatments while gonyautoxins 2 and 3 (combined) decreased by almost 100% in the Gaspé samples and by about 90% in the Fundy samples with the same cooking treatments. Trace amounts of saxitoxin or gonyautoxins 2 and 3 were detected in some samples of tail or claw meat before or after cooking. In vitro boiling of raw hepatopancreas for up to 30 min led to no change in total or individual PSP concentration, indicating that the toxins in cooked lobster are not removed through chemical decomposition but are leached out during the loss of water. PMID:9237337

Lawrence, J F; Maher, M; Watson-Wright, W

1994-01-01

218

Building heat conservation and the feasibility of solar hot water heating in Long Island shellfish hatcheries  

SciTech Connect

Temperature regulation is a vital component of any aquaculture system. Existing facilities can be retrofitted with extra insulation, waste heat recovery systems and in some cases, active solar water heating. Those aquaculture ventures that seek to raise organisms to market size under controlled conditions are currently hindered by high operating costs, including fuel. These outfits can also benefit from conservation and alternative energy technologies. In addition, the industry may be more willing to cultivate species normally restricted by climatic conditions if a less expensive source of heating were available. This report focuses on three of the bivalve shellfish aquaculture enterprises of Long Island, New York. In the 1978 to 1979 growing season, Long Island shellfish growers collectively burned over 50,000 gallons of heating oil to warm their hatchery waters and buildings. Since then, heating oil prices have doubled. Currently, some growers are limited by these fuel costs from beginning production earlier in the season. In this report, several heat conservation measures are discussed, and the feasibility of active solar hot water is examined.

Berg, D.L.

1980-01-01

219

Three-Year Study To Assess Human Enteric Viruses in Shellfish  

PubMed Central

The main pathogenic enteric viruses able to persist in the environment, such as hepatitis A virus (HAV), Norwalk-like virus (NLV), enterovirus (EV), rotavirus (RV), and astrovirus (AV), were detected by reverse transcription-PCR and hybridization in shellfish during a 3-year study. Oyster samples (n = 108), occasionally containing bacteria, were less frequently contaminated, showing positivity for AV (17%), NLV (23%), EV (19%), and RV (27%), whereas mussel samples, collected in areas routinely impacted by human sewage, were more highly contaminated: AV (50%), HAV (13%), NLV (35%), EV (45%), and RV (52%). Sequences obtained from HAV and NLV amplicons showed a great variety of strains, especially for NLV (strains close to Mexico, Snow Mountain Agent, or Norwalk virus). Viral contamination was mainly observed during winter months, although there were some seasonal differences among the viruses. This first study of virus detection over a fairly long period of time suggests that routine analysis of shellfish by a molecular technique is feasible. PMID:10919776

Le Guyader, F.; Haugarreau, L.; Miossec, L.; Dubois, E.; Pommepuy, M.

2000-01-01

220

Viral Pollution in the Environment and in Shellfish: Human Adenovirus Detection by PCR as an Index of Human Viruses  

Microsoft Academic Search

A study of the presence of human viruses (adenoviruses, enteroviruses, and hepatitis A viruses (HAVs)) in environmental and shellfish samples was carried out by applying DNA and cDNA amplification techniques by PCR. The detection of human adenoviruses by PCR was also examined as a potential molecular test to monitor viral pollution. The samples studied were urban and slaughterhouse sewage, river

SONIA PINA; MONTSERRAT PUIG; FRANCISCO LUCENA; JOAN JOFRE; ROSINA GIRONES

1998-01-01

221

Interannual variability of shellfish toxicity in the Gulf of Maine: Time and space patterns and links to environmental variability  

E-print Network

21-year time series that are cross-correlated with concurrent monthly environmental metrics of Gulf circulation model hindcasts. These analyses provide three main results. First, toxicity time series showInterannual variability of shellfish toxicity in the Gulf of Maine: Time and space patterns

Townsend, David W.

222

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...

223

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

PubMed

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

Groth, Edward

2010-04-01

224

Analysis of coastal and offshore aquaculture: Application of the FARM model to multiple systems and shellfish species  

Microsoft Academic Search

The Farm Aquaculture Resource Management (FARM) model has been applied to several shellfish species and aquaculture types. The performance of the FARM model, developed to simulate potential harvest, key financial data, and water quality impacts at the farm-scale, was tested in five systems in the European Union: Loch Creran, Scotland (Pacific oyster), Pertuis Breton, France (blue mussel), Bay of Piran,

J. G. Ferreira; A. Sequeira; A. J. S. Hawkins; A. Newtonc; T. D. Nickell; R. Pastres; J. Forte; A. Bodoy; S. B. Bricker

2009-01-01

225

Management of productivity, environmental effects and profitability of shellfish aquaculture — the Farm Aquaculture Resource Management (FARM) model  

Microsoft Academic Search

This paper describes a model for assessment of coastal and offshore shellfish aquaculture at the farm-scale. The Farm Aquaculture Resource Management (FARM) model is directed both at the farmer and the regulator, and has three main uses: (i) prospective analyses of culture location and species selection; (ii) ecological and economic optimisation of culture practice, such as timing and sizes for

J. G. Ferreira; A. J. S. Hawkins; S. B. Bricker

2007-01-01

226

Effects of low carbohydrate diets high in red meats or poultry, fish and shellfish on plasma lipids and weight loss  

Microsoft Academic Search

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

Bridget A Cassady; Nicole L Charboneau; Emily E Brys; Kristin A Crouse; Donald C Beitz; Ted Wilson

2007-01-01

227

Diversity of Infectious Pancreatic Necrosis Virus Strains Isolated from Fish, Shellfish, and Other Reservoirs in Northwestern Spain  

Microsoft Academic Search

A comparison was done of 231 strains of birnavirus isolated from fish, shellfish, and other reservoirs in a survey study that began in 1986 in Galicia (northwestern Spain). Reference strains from all of the infectious pancreatic necrosis virus serotypes were included in the comparison, which was done by neutralization tests and agarose and polyacrylamide gel electrophoresis of the viral genome.

J. M. Cutrin; J. G. Olveira; J. L. Barja; C. P. Dopazo

2000-01-01

228

The role of submarine groundwater discharge (SGD) in nutrient budgets of Gamak Bay, a shellfish farming bay, in Korea  

Microsoft Academic Search

In order to evaluate the main source of nutrients fueling primary production in a shellfish farming bay (Gamak Bay) in the southern sea of Korea, we measured the concentrations of nutrients and radium isotopes in stream water, surface seawater, and coastal groundwater in May 2006, August 2006, and November 2007. Using a 226Ra mass balance model, submarine groundwater discharge (SGD)

Dong-Woon Hwang; Guebuem Kim; Won-Chan Lee; Hyun-Taik Oh

2010-01-01

229

The farming of aquatic organisms, whether fish, shellfish, plants, or algae, is subject to a variety of risks.  

E-print Network

Overview The farming of aquatic organisms, whether fish, shellfish, plants, or algae, is subject of your enterprise. In a business context, risk management is about reducing the cost of risk. Aquacul of risk at the lowest possible cost. How Understanding financial statements provides the foundation

Florida, University of

230

Environmental links to interannual variability in shellfish toxicity in Cobscook Bay and eastern Maine, a strongly tidally mixed coastal region  

NASA Astrophysics Data System (ADS)

The Gulf of Maine experiences annual closures of shellfish harvesting due to the accumulation of toxins produced by dinoflagellates of the genus Alexandrium. Factors controlling the timing, location, and magnitude of these events in eastern Maine remain poorly understood. Previous work identified possible linkages between interannual variability of oceanographic variables and shellfish toxicity along the western Maine coastline but no such linkages were evident along the eastern Maine coast in the vicinity of Cobscook Bay, where strong tidal mixing tends to reduce seasonal variability in oceanographic properties. Using 21 years (1985-2005) of shellfish toxicity data, interannual variability in two metrics of annual toxicity, maximum magnitude and total annual toxicity, from stations in the Cobscook Bay region are examined for relationships to a suite of available environmental variables. Consistent with earlier work, no (or only weak) correlations were found between toxicity and oceanographic variables, even those very proximate to the stations such as local sea surface temperature. Similarly no correlations were evident between toxicity and air temperature, precipitation or relative humidity. The data suggest possible connections to local river discharge, but plausible mechanisms are not obvious. Correlations between toxicity and two variables indicative of local meteorological conditions, dew point and atmospheric pressure, both suggest a link between increased toxicity in these eastern Maine stations and weather conditions characterized by clearer skies/drier air (or less stormy/humid conditions). As no correlation of opposite sign was evident between toxicity and local precipitation, one plausible link is through light availability and its positive impact on phytoplankton production in this persistently foggy section of coast. These preliminary findings point to both the value of maintaining long-term shellfish toxicity sampling and a need for inclusion of weather variability in future modeling studies aimed at development of a more mechanistic understanding of factors controlling interannual differences in eastern Gulf of Maine shellfish toxicity.

Horecka, Hannah M.; Thomas, Andrew C.; Weatherbee, Ryan A.

2014-05-01

231

A comparison of virus concentration methods for molecular detection and characterization of rotavirus in bivalve shellfish species.  

PubMed

The objectives of this study were to develop a method for concentrating rotavirus, to assess the detection rate, and to characterize the genotype of naturally occurring rotavirus in bivalve shellfish species; including oysters (Saccostrea forskali), cockles (Anadara nodifera), and mussels (Perna viridis). The results demonstrated that an adsorption-twice elution-extraction method was less-time consuming method of concentrating the spiked rotavirus, yielding high sensitivity of 1.14 genome copies/g of digestive tissues from all three shellfish species, as detected using an RT-nested PCR. In seeding experiments, rotavirus as low as 1.39 genome copies was able to be detected in 4 g of digestive tissues or per sample. In the period of August 2011 to July 2012, of the 300 bivalve shellfish samples collected and tested, 24 (8.0%) were found to be contaminated with rotavirus, the figures being: oysters, 13/100 samples; mussels, 10/100 samples; and cockles, 1/100 samples. By DNA sequencing of the RT-nested PCR products and phylogenetic analysis, the rotaviruses detected were classified into G1, lineage II (4 samples); G3 (10 samples): lineage I (3 samples), lineage IIIc (3 samples), lineage IIId (3 samples), lineage IV (1 sample); G9 (6 samples); and G12, lineage III (1 sample). These findings suggest that this virus concentration method provides high sensitivity for the detection of rotavirus from the three bivalve shellfish species. The prevalence of rotavirus and the identified genotypes contribute to the molecular epidemiology of rotavirus in different shellfish species. PMID:25475280

Kittigul, Leera; Singhaboot, Yutatirat; Chavalitshewinkoon-Petmitr, Porntip; Pombubpa, Kannika; Hirunpetcharat, Chakrit

2015-04-01

232

Toxic marine microalgae and shellfish poisoning in the British isles: history, review of epidemiology, and future implications  

PubMed Central

The relationship between toxic marine microalgae species and climate change has become a high profile and well discussed topic in recent years, with research focusing on the possible future impacts of changing hydrological conditions on Harmful Algal Bloom (HAB) species around the world. However, there is very little literature concerning the epidemiology of these species on marine organisms and human health. Here, we examine the current state of toxic microalgae species around the UK, in two ways: first we describe the key toxic syndromes and gather together the disparate reported data on their epidemiology from UK records and monitoring procedures. Secondly, using NHS hospital admissions and GP records from Wales, we attempt to quantify the incidence of shellfish poisoning from an independent source. We show that within the UK, outbreaks of shellfish poisoning are rare but occurring on a yearly basis in different regions and affecting a diverse range of molluscan shellfish and other marine organisms. We also show that the abundance of a species does not necessarily correlate to the rate of toxic events. Based on routine hospital records, the numbers of shellfish poisonings in the UK are very low, but the identification of the toxin involved, or even a confirmation of a poisoning event is extremely difficult to diagnose. An effective shellfish monitoring system, which shuts down aquaculture sites when toxins exceed regularity limits, has clearly prevented serious impact to human health, and remains the only viable means of monitoring the potential threat to human health. However, the closure of these sites has an adverse economic impact, and the monitoring system does not include all toxic plankton. The possible geographic spreading of toxic microalgae species is therefore a concern, as warmer waters in the Atlantic could suit several species with southern biogeographical affinities enabling them to occupy the coastal regions of the UK, but which are not yet monitored or considered to be detrimental. PMID:21645342

2011-01-01

233

Levels of perfluorinated compounds in raw and cooked Mediterranean finfish and shellfish.  

PubMed

Perfluorinated compounds (PFCs) were analyzed in several species of small Mediterranean fish and shellfish, all of which are popular in Greek diet. Analysis was conducted in raw samples and in samples cooked by the two ways preferred in Greek cuisine, i.e. fried in olive oil and grilled. PFCs above the detection limit were found in all raw samples except sardine, mussel and squid. The predominant PFC was PFOS (perfluorooctane sulfonate), the highest concentration of which was measured in picarel (20.4ngg(-1) fresh weight). The PFOS values for the rest of the samples were between

Vassiliadou, Irene; Costopoulou, Danae; Kalogeropoulos, Nick; Karavoltsos, Sotirios; Sakellari, Aikaterini; Zafeiraki, Effrosyni; Dassenakis, Manos; Leondiadis, Leondios

2015-05-01

234

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

SciTech Connect

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.

Eisenberg, M.; Topping, J.J.

1984-10-01

235

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

PubMed

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

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

2015-04-01

236

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

PubMed

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

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

237

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

PubMed Central

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 ?g 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

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

2008-01-01

238

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

SciTech Connect

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.

Ogata, M.; Miyake, Y.

1980-11-01

239

A High-Throughput, Microtiter Plate Assay for Paralytic Shellfish Poisons Using the Saxitoxin-Specific Receptor, Saxiphilin  

Microsoft Academic Search

An isoform of the paralytic shellfish poison (PSP)-specific receptor saxiphilin, from the tropical centipedeEthmostigmus rubripes,was used as the basis for a radiometric, high-throughput, microtiter plate assay for this group of toxins. Characterization of the assay revealed that it was able to detect several representatives from the various structural PSP subgroups and yet was insensitive toward tetrodotoxin. To test the utility

Lyndon E. Llewellyn; Jason Doyle; Andrew P. Negri

1998-01-01

240

Multidetection of paralytic, diarrheic, and amnesic shellfish toxins by an inhibition immunoassay using a microsphere-flow cytometry system.  

PubMed

The presence of paralytic shellfish poisoning (PSP), diarrheic shellfish poisoning (DSP), and amnesic shellfish poisoning (ASP) toxins in seafood is a severe and growing threat to human health. In order to minimize the risks of human exposure, the maximum content of these toxins in seafood has been limited by legal regulations worldwide. The regulated limits are established in equivalents of the main representatives of the groups: saxitoxin (STX), okadaic acid (OA), and domoic acid (DA), for PSP, DSP, and ASP, respectively. In this study a multidetection method to screen shellfish samples for the presence of these toxins simultaneously was developed. Multiplexing was achieved using a solid-phase microsphere assay coupled to flow-fluorimetry detection, based on the Luminex xMap technology. The multidetection method consists of three simultaneous competition immunoassays. Free toxins in solution compete with STX, OA, or DA immobilized on the surface of three different classes of microspheres for binding to specific monoclonal antibodies. The IC50 obtained in the buffer was similar in single- and multidetection: 5.6 ± 1.1 ng/mL for STX, 1.1 ± 0.03 ng/mL for OA, and 1.9 ± 0.1 ng/mL for DA. The sample preparation protocol was optimized for the simultaneous extraction of STX, OA, and DA with a mixture of methanol and acetate buffer. The three immunoassays performed well with mussel and scallop matrixes displaying adequate dynamic ranges and recovery rates (around 90% for STX, 80% for OA, and 100% for DA). This microsphere-based multidetection immunoassay provides an easy and rapid screening method capable of detecting simultaneously in the same sample three regulated groups of marine toxins. PMID:23859142

Fraga, María; Vilariño, Natalia; Louzao, M Carmen; Rodríguez, Paula; Campbell, Katrina; Elliott, Christopher T; Botana, Luis M

2013-08-20

241

Bioaccumulation of paralytic shellfish poisoning (PSP) toxins from the cyanobacterium Anabaena circinalis by the freshwater mussel Alathyria condola  

Microsoft Academic Search

The Australian fresh-water mussel Alathyria condola accumulated high levels of paralytic shellfish poisoning (PSP) toxins when fed the neurotoxic cyanobacterium Anabaena circinalis, shown recently to contain high concentrations of C-toxins and gonyautoxins. Significant accumulation (>; 80 ?g\\/100 g of mussel flesh) was detected following 2–3 days exposure to water containing 2 × 105 cells\\/mlA. circinalis. Only trace accumulation of PSP

Andrew P. Negri; Gary J. Jones

1995-01-01

242

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

PubMed Central

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 strong measures to prevent, monitor, and manage the possible invasion of C. maenas. PMID:25408891

Mach, Megan E; Chan, Kai MA

2014-01-01

243

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

SciTech Connect

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.)

Not Available

1992-07-01

244

Occurrence of dioxins (PCDDs, PCDFs) and polychlorinated biphenyls (PCBs) in wild, farmed and processed fish, and shellfish.  

PubMed

Forty-eight composite samples of the most commonly consumed fish and shellfish species were prepared from up to 60 individual subsamples of each species and analysed for chlorinated dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs). These included 24 species of fresh wild fish, seven of farmed fish, seven of fresh shellfish, and ten processed fish and shellfish products. The ISO 17025-accredited analytical methodology used is consistent with the requirements given in European Commission Directive 2002/69/EC. Concentrations ranged from 0.03 ng kg(-1) PCDD/F plus PCB World Health Organization-toxic equivalent quantity (WHO-TEQ) for a sample of surimi, to approximately 6 ng kg(-1) for wild pilchards/sardines. The corresponding range for the ?ICES-6 PCBs was 0.04 ? g kg(-1) to approximately 47 ? g kg(-1). None of the samples showed concentrations above the European Union maximum permitted limits. Averaged PCDD/F and PCB concentrations for the two groups of farmed and wild fish show that there is little difference between the two categories, although individual species may show variations depending on factors such as the sampling location. PMID:24784962

Fernandes, A R; Mortimer, D N; Rose, M; Knowles, T G; White, S; Gem, M

2009-01-01

245

Mathematical model for viral depuration kinetics in shellfish: An useful tool to estimate the risk for the consumers.  

PubMed

Enteric virus depuration from shellfish is a complex biological process that may be influenced by biological properties of the mollusc and/or virus species. On the basis of previous experimental data, a mathematical model was developed to characterize the kinetics of viral elimination during the depuration process. The experimental data consisted on twenty depuration trials, each with 60 kg of Manila clams (Venerupis philippinarum ) and mediterranean mussels (Mytilus galloprovincialis) previously subjected to bioaccumulation with HAV or MNV-1 (as a surrogate for human norovirus), that were performed in an experimental depuration system during 7 days. It was observed that although viral loads decay along depuration, a residual viral load remains at the end of the process suggesting a decomposition of viral load in a diluted load (susceptible of depuration) and a non-diluted load (unavailable to depurate). The model yielded a general equation, which can predict the viral load at any depuration time knowing the specific filtration rate, dependent on the bivalve species, and specific viral properties. The mathematical model can be combined with quantitative risk assessment calculations to determine the safety of the depurated shellfish, which can be very helpful not only for shellfish producers but also to public health authorities. PMID:25846934

Polo, David; Feal, Xabier; Romalde, Jesús L

2015-08-01

246

A graphene-based electrochemical competitive immunosensor for the sensitive detection of okadaic acid in shellfish  

NASA Astrophysics Data System (ADS)

A novel graphene-based voltammetric immunosensor for sensitive detection of okadaic acid (OA) was developed. A simple and efficient electrografting method was utilized to functionalize graphene-modified screen-printed carbon electrodes (GSPE) by the electrochemical reduction of in situ generated 4-carboxyphenyl diazonium salt in acidic aqueous solution. Next, the okadaic acid antibody was covalently immobilized on the carboxyphenyl modified graphene electrodes via carbodiimide chemistry. Square wave voltammetry (SWV) was used to investigate the stepwise assembly of the immunosensor. A competitive assay between OA and a fixed concentration of okadaic acid-ovalbumin conjugate (OA-OVA) for the immobilized antibodies was employed for the detection of okadaic acid. The decrease of the [Fe(CN)6]3-/4- reduction peak current in the square wave voltammetry for various concentrations of okadaic acid was used for establishing the calibration curve. A linear relationship between the SWV peak current difference and OA concentration was obtained up to ~5000 ng L-1. The developed immunosensor allowed a detection limit of 19 ng L-1 of OA in PBS buffer. The matrix effect studied with spiked shellfish tissue extracts showed a good percentage of recovery and the method was also validated with certified reference mussel samples.A novel graphene-based voltammetric immunosensor for sensitive detection of okadaic acid (OA) was developed. A simple and efficient electrografting method was utilized to functionalize graphene-modified screen-printed carbon electrodes (GSPE) by the electrochemical reduction of in situ generated 4-carboxyphenyl diazonium salt in acidic aqueous solution. Next, the okadaic acid antibody was covalently immobilized on the carboxyphenyl modified graphene electrodes via carbodiimide chemistry. Square wave voltammetry (SWV) was used to investigate the stepwise assembly of the immunosensor. A competitive assay between OA and a fixed concentration of okadaic acid-ovalbumin conjugate (OA-OVA) for the immobilized antibodies was employed for the detection of okadaic acid. The decrease of the [Fe(CN)6]3-/4- reduction peak current in the square wave voltammetry for various concentrations of okadaic acid was used for establishing the calibration curve. A linear relationship between the SWV peak current difference and OA concentration was obtained up to ~5000 ng L-1. The developed immunosensor allowed a detection limit of 19 ng L-1 of OA in PBS buffer. The matrix effect studied with spiked shellfish tissue extracts showed a good percentage of recovery and the method was also validated with certified reference mussel samples. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32146g

Eissa, Shimaa; Zourob, Mohammed

2012-11-01

247

A comparative study of the mechanical properties of Mytilid byssal threads.  

PubMed

Mytilid bivalves employ a set of threads (the byssus) to attach themselves to both hard and soft substrates. In this study, we measured the mechanical properties of byssal threads from two semi-infaunal mytilids (Geukensia demissa Dillwyn and Modiolus modiolus Linnaeus) and two epifaunal mytilids (Mytilus californianus Conrad and Mytilus edulis Linnaeus). We compared material properties with and without the assumption that changes of length and area during tensile testing are insignificant, demonstrating that previous researchers have overestimated extensibility values by 30% and may also have underestimated strength values. We detected significant differences in thread properties among tested mytilid species, contrary to previous findings. Threads from semi-infaunal species were significantly thinner than those from epifaunal species, perhaps to allow the production of a greater number of threads, which form a dense network within the substrate. Geukensia demissa threads were weaker than those of the other species, and had a significantly lower stiffness at failure. Modiolus modiolus threads were significantly stiffer than M. edulis threads but also significantly less extensible, suggesting a trade-off between stiffness and extensibility. The only thread property that did not show significant differences across species was toughness - even when byssal threads differ in strength or stiffness, they seem to absorb similar amounts of energy per unit volume prior to failure. This study reveals notable differences between the byssal thread properties of different mytilid bivalves and provides a reliable and thorough methodology for future comparative studies. PMID:19411537

Pearce, Trevor; Labarbera, Michael

2009-05-01

248

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

USGS Publications Warehouse

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.

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

2011-01-01

249

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

PubMed

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 ?mol/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

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

250

[Microphytobenthos assemblage mapping by spatial visible-infrared remote sensing in a shellfish ecosystem].  

PubMed

The aim of this work is to assess the use of (SPOT) multispectral visible infrared remote sensing to study microphytobentos assemblages in a shellfish ecosystem (Bay of Bourgneuf, France). SPOT satellite images (acquired at low tide in spring or autumn between 1986 and 1998) were calibrated using in situ radiometric data, and the normalised vegetation index (NDVI) obtained from these images showed microphytobenthos on bay mudflats. Proliferation was mainly along a north-south strip, essentially localised around the +2 m isobath and covering a surface area of 19 to 25% of the total mudflat area studied (420 to 550 ha). Three factors seem to be responsible for the spatial structure of the assemblages: bathymetry, nutrient input from the Falleron River and its channel, and the location of oyster-farming areas. Although spatial and spectral resolutions of multispectral remote sensing data have certain limitations, this approach opens up a new field of application for hyperspectral remote sensing, particularly for synoptic mapping of biomass distribution. PMID:12876890

Méléder, Vona; Launeau, Patrick; Barillé, Laurent; Rincé, Yves

2003-04-01

251

Shellfish dredging pushes a flexible avian top predator out of a marine protected area.  

PubMed

There is a widespread concern about the direct and indirect effects of industrial fisheries; this concern is particularly pertinent for so-called "marine protected areas" (MPAs), which should be safeguarded by national and international law. The intertidal flats of the Dutch Wadden Sea are a State Nature Monument and are protected under the Ramsar convention and the European Union's Habitat and Birds Directives. Until 2004, the Dutch government granted permission for ~75% of the intertidal flats to be exploited by mechanical dredgers for edible cockles (Cerastoderma edule). Here we show that dredged areas belonged to the limited area of intertidal flats that were of sufficient quality for red knots (Calidris canutus islandica), a long-distance migrant molluscivore specialist, to feed. Dredging led to relatively lower settlement rates of cockles and also reduced their quality (ratio of flesh to shell). From 1998 to 2002, red knots increased gizzard mass to compensate for a gradual loss in shellfish quality, but this compensation was not sufficient and led to decreases in local survival. Therefore, the gradual destruction of the necessary intertidal resources explains both the loss of red knots from the Dutch Wadden Sea and the decline of the European wintering population. This study shows that MPAs that do not provide adequate protection from fishing may fail in their conservation objectives. PMID:17105350

van Gils, Jan A; Piersma, Theunis; Dekinga, Anne; Spaans, Bernard; Kraan, Casper

2006-11-01

252

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

PubMed

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

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

2014-12-01

253

Heavy metals concentrations in fish and shellfish from eastern Mediterranean Sea: consumption advisories.  

PubMed

The present study evaluate concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), nickel (Ni), vanadium (V) and zinc (Zn) in fish and shellfish from the Gulf of Catania. Heavy metal analysis was carried on with an ICP-MS, and consumption rates advisory for minimizing chronic systemic and non cancer endpoints in child and adults have been estimated. Among metals investigated, only Cd and Pb have a limit set by European Community for human consumption, and the thresholds were not been exceeded in analyzed species. The As, toxic in its inorganic form, have not a regulatory limit yet, but the Environmental Protection Agency and the World Health Organization provide a reference dose, a cancer slope factor and a tolerable intake, applicable in the risk factors assessment. Arsenic target hazard quotient (THQ) values, suggest that human should minimizing meals/week of analyzed species to avoid deleterious effect during lifetime, furthermore, with As cancer risk assessment, for most of the fish, the risk for cancer is greater than the acceptable lifetime risk of 10(-5). Our results give important finding about the consumption limits on certain metals, especially for As, all for minimizing potential health risks in population. PMID:23211443

Copat, Chiara; Arena, Giovani; Fiore, Maria; Ledda, Caterina; Fallico, Roberto; Sciacca, Salvatore; Ferrante, Margherita

2013-03-01

254

Occurrence of Vibrio vulnificus in fish and shellfish available from markets in China.  

PubMed

Vibrio vulnificus is a naturally occurring estuarine bacterium often associated with disease such as septicemia in humans following consumption of raw and lightly cooked seafood. In China and neighboring countries, rapid economic growth has encouraged increased consumption of seafood, and dietary habits are changing, with more people eating raw fish. In this study, the prevalence of V. vulnificus was investigated in 48 samples from 11 species of live seafood available from markets in coastal cities of China. The bacterium was detected in four of four razor clam samples, in seven of seven giant tiger prawn samples, and in five of nine mantis shrimp samples. The bacterium was also found in water samples of the prawn aquaria at the markets. The maximum level of V. vulnificus was 3.4 log CFU/g in the razor clam samples and 4.9 log CFU/g in the prawn samples by a direct spreading method. Differential bacterial counts on the prawn body revealed that most of the bacteria were found on the shells (exoskeletons), with very few in the edible muscle. However, dense populations can be found in the intestines. Biochemical tests indicated that the isolates of V. vulnificus were biotype 1 strain, which is pathogenic to humans. These isolates were susceptible to ampicillin, penicillin, kanamycin, streptomycin, and erythromycin. These results suggest that V. vulnificus is a potential health hazard to humans in cities consuming and handling live shellfish, especially giant tiger prawns. PMID:15330524

Yano, Yutaka; Yokoyama, Masahito; Satomi, Masataka; Oikawa, Hiroshi; Chen, Shun-Sheng

2004-08-01

255

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

256

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

SciTech Connect

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.

Murphy, D.L. [Maryland Dept. of the Environment, Baltimore, MD (United States)

1995-12-31

257

Detection and quantification of hepatitis A virus and norovirus in Spanish authorized shellfish harvesting areas.  

PubMed

An 18-month survey was conducted in ten class "B" harvesting areas from two Galician Rias (NW of Spain), the most important bivalve production area in Europe, to determine the prevalence of hepatitis A virus (HAV) and human norovirus (NoV), including genogroups I (GI) and II (GII). Quantification was performed by reverse transcription real-time PCR (RT-qPCR), according to the recently developed standard method ISO/TS 15216-1:2013. Four bivalve species were studied, including wild and cultured mussels (Mytilus galloprovincialis), clams (Venerupis philippinarum and Venerupis decussata) and cockles (Cerastoderma edule). Overall, 55.4% of samples were contaminated by at least one of the studied viruses, being detected the simultaneous presence of two or three viruses in 11.3% of the cases. NoV GI was the most prevalent virus (32.1%), followed by NoV GII (25.6%) and HAV (10.1%). Cultured mussels showed the highest percentage of positive samples (61.4%), followed by cockles (59.4%), wild mussels (54.3%) and clams (38.7%). Viral contamination levels for most of the positive samples ranged from 10(2) to 10(3) RNA copies/g of digestive tissue (RNAc/g DT). The presence of viral contamination was statistically higher (P<0.0001) in warm months (April to September) than in cold months (October to March). The data presented here may contribute to the development of more representative sampling strategies, in monitoring and management of shellfish growing areas as well as being useful in a future scenario in which viral critical values are adopted in legislation. PMID:25462922

Polo, David; Varela, Miguel F; Romalde, Jesús L

2015-01-16

258

Tracing the origin of paralytic shellfish toxins in scallop Patinopecten yessoensis in the northern Yellow Sea.  

PubMed

Some dinoflagellate species within the genera Alexandrium, Gymnodinium and Pyrodinium are well-known producers of paralytic shellfish toxins (PST), which led to many poisoning incidents around the world. In the northern Yellow Sea, an important mariculture zone for scallop Patinopecten yessoensis, PST have been frequently detected from scallops. However, there is little knowledge concerning PST-producing microalgae in this region so far. In cruises carried out in 2011 and 2012, scallop and phytoplankton samples were collected from the northern Yellow Sea. PST were detected from scallops by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). Toxin content and profile were remarkably different among the four tissues, i.e. viscera, adductor muscle, mantle and gonad, suggesting apparent toxin transfer and transformation in scallops. Viscera always had the highest content of PST dominated by low-potency N-sulfocarbamoyl toxins C1 and C2, which closely resembled the toxin profiles of net-concentrated phytoplankton samples in spring. Based on the morphological features, cells of Alexandrium spp. in net-concentrated phytoplankton samples were picked out and a partial sequence of the large subunit ribosomal RNA gene (LSU rDNA) was amplified using a single-cell polymerase chain reaction (PCR) method. Cells of both toxic A. tamarense species complex and non-toxic A. affine were identified from the phytoplankton samples based on the partial LSU rDNA sequence information. According to these findings, it is implied that A. tamarense species complex is the major toxic species related to PST contamination in scallops of the northern Yellow Sea. The presence of both toxic and non-toxic Alexandrium spp. in this region requires for a species-specific method to monitor the distribution and dynamics of A. tamarense species complex. PMID:24124903

Chen, Jian-Hua; Yu, Ren-Cheng; Gao, Yan; Kong, Fan-Zhou; Wang, Yun-Feng; Zhang, Qing-Chun; Kang, Zhen-Jun; Yan, Tian; Zhou, Ming-Jiang

2013-01-01

259

Phylogeography of cylindrospermopsin and paralytic shellfish toxin-producing nostocales cyanobacteria from mediterranean europe (Spain).  

PubMed

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 ?g 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

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

2014-02-01

260

Investigation of extraction and analysis techniques for Lyngbya wollei derived Paralytic Shellfish Toxins.  

PubMed

Paralytic Shellfish Toxins (PSTs) are highly toxic metabolic by-products of cyanobacteria and dinoflagellates. The filamentous cyanobacterium Lyngbya wollei produces a unique set of PSTs, including L. wollei toxins (LWT) 1-6. The accurate identification and quantification of PSTs from Lyngbya filaments is challenging, but critical for understanding toxin production and associated risk, as well as for providing baseline information regarding the potential for trophic transfer. This study evaluated several approaches for the extraction and analysis of PSTs from field-collected L. wollei dominated algal mats. Extraction of PSTs from lyophilized Lyngbya biomass was assessed utilizing hydrochloric acid and acetic acid at concentrations of 0.001-0.1 M. Toxin profiles were then compared utilizing two analysis techniques: pre-column oxidation (peroxide and periodate) High Performance Liquid Chromatography (HPLC) with Fluorescence (FL) detection and LC coupled with Mass Spectrometry (MS). While both acid approaches efficiently extracted PSTs, hydrochloric acid was found to convert the less toxic LWT into the more toxic decarbamoylgonyautoxins 2&3 (dcGTX2&3) and decarbamoylsaxitoxin (dcSTX). In comparison, extraction with 0.1 M acetic acid preserved the original toxin profile and limited the presence of interfering co-extractants. Although pre-chromatographic oxidation with HPLC/FL was relatively easy to setup and utilize, the method did not resolve the individual constituents of the L. wollei derived PST profile. The LC/MS method allowed characterization of the PSTs derived from L. wollei, but without commercially available LWT 1-6 standards, quantitation was not possible for the LWT. In future work, evaluation of the risk associated with L. wollei derived PSTs will require commercially available standards of LWT 1-6 for accurate determinations of total PST content and potency. PMID:22960450

Foss, Amanda J; Phlips, Edward J; Aubel, Mark T; Szabo, Nancy J

2012-11-01

261

Environmental effects of modified clay flocculation on Alexandrium tamarense and paralytic shellfish poisoning toxins (PSTs).  

PubMed

Among various mitigation strategies for harmful algal blooms (HABs), the flocculation of algal cells by using modified clay (MC) has been widely applied in the field, particularly in Japan, Korea and China. However, to examine the long-term effects and the environmental safety of this method, we investigated alterations in macronutrients and paralytic shellfish poisoning toxins (PSTs) induced by the application of MC treatment to a toxic bloom, Alexandrium tamarense. The control, algal cells grew in nature condition (A1), was compared to the only MC flocculation (A2) and the MC-sediment co-matrix systems of A. tamarense (A3). The low-dosage of 0.25gL(-)(1) MC could efficiently remove >90% of the A. tamarense cells within 3.5h. The mechanisms underlying the effects elicited by MC flocculation on nutrient cycling, PSTs and Chl-a degradation were also discussed. This study demonstrated that MC treatment was able to significantly remove the macronutrients (43-60% TP removal and 17-30% TN removal) and scavenge most of the PSTs from seawater, thereby speeding up the nutrient settling and the transformation and degradation of PSTs (83% decreasing in A2). Simultaneously, the study firstly demonstrated the potential detoxification of PSTs by using MC treatment, from the high toxicity of gonyautoxin 1 and 4 (GTX1 and GTX4) to the lower toxicity decarbamoyl gonyautoxins (dcGTX3) and gonyautoxin 2 (GTX2), particularly within the water-sediment environment during the two month incubation. PMID:25721022

Lu, Guangyuan; Song, Xiuxian; Yu, Zhiming; Cao, Xihua; Yuan, Yongquan

2015-05-01

262

Prevalence of human noroviruses in frozen marketed shellfish, red fruits and fresh vegetables.  

PubMed

Noroviruses (NoVs), currently recognised as the most common human food-borne pathogens, are ubiquitous in the environment and can be transmitted to humans through multiple foodstuffs. In this study, we evaluated the prevalence of human NoV genogroups I (GI) and II (GII) in 493 food samples including soft red fruits (n = 200), salad vegetables (n = 210) and bivalve mollusc shellfish (n = 83), using the Bovine Enterovirus type 1 as process extraction control for the first time. Viral extractions were performed by elution concentration and genome detection by TaqMan Real-Time RT-PCR (RT-qPCR). Experimental contamination using hepatitis A virus (HAV) was used to determine the limit of detection (LOD) of the extraction methods. Positive detections were obtained from 2 g of digestive tissues of oysters or mussels kept for 16 h in seawater containing 2.0-2.7 log10 plaque-forming units (PFU)/L of HAV. For lettuces and raspberries, the LOD was, respectively, estimated at 2.2 and 2.9 log10 PFU per 25 g. Of the molluscs tested, 8.4 and 14.4% were, respectively, positive for the presence of GI NoV and GII NoV RNA. Prevalence in GI NoVs varied from 11.9% for the salad vegetables samples to 15.5% for the red soft fruits. Only 0.5% of the salad and red soft fruits samples were positive for GII NoVs. These results highlight the high occurrence of human NoVs in foodstuffs that can be eaten raw or after a moderate technological processing or treatment. The determination of the risk of infection associated with an RT-qPCR positive sample remains an important challenge for the future. PMID:24923255

Loutreul, Julie; Cazeaux, Catherine; Levert, Delphine; Nicolas, Aline; Vautier, Sandrine; Le Sauvage, Anne Laure; Perelle, Sylvie; Morin, Thierry

2014-09-01

263

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

PubMed

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 ?-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 ? ?-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

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

2015-01-01

264

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

PubMed Central

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

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

2014-01-01

265

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

PubMed Central

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 ?g 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

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

2014-01-01

266

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

NASA Astrophysics Data System (ADS)

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.

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

267

Plutonium and americium uptake in rats fed with Cumbrian shellfish--implications for estimates of dose to man.  

PubMed

Winkles (Littorina littorea) and mussels (Mytilus edulis) collected on the Cumbrian coast contain americium-241 and isotopes of plutonium discharged from the nuclear-fuel reprocessing plant at Sellafield. Shellfish have been fed to rats and measurements made of the gastrointestinal absorption of the actinides. For shellfish collected over a 1-year period from March 1983 to February 1984, the average values for the fractional absorption of plutonium and americium were 9 x 10(-4) and 3 x 10(-4), respectively, for winkles and 1.5 x 10(-3) and 6 x 10(-4), respectively, for mussels. Comparisons with results for winkles collected in December 1981 and mussels collected in July 1982 suggest that there may be considerable seasonal variation in the availability of the actinides for absorption. The results suggest that in calculations of doses to individuals consuming shellfish in west Cumbria, it may be prudent to examine the effect of using the new ICRP gut transfer factor of 1 x 10(-3) for both actinides, in comparison with the value of 5 x 10(-4) recommended previously by NRPB. The use of 1 x 10(-3) would increase the estimate of the committed effective dose equivalent for 1985 intakes, from the value of 0.73 mSv calculated by the Ministry of Agriculture, Fisheries and Food, to 1.29 mSv. However, taking into account up-to-date estimates of the retention of the actinides in liver and bone would reduce this value to 1.07 mSv. If, in addition, allowance is made for the effect of the burial and recycling of actinides in bone, a significant reduction in the dose estimate could result; for example, the use of one proposed dynamic bone model would reduce the value from 1.07 to 0.54 mSv. PMID:3363317

Harrison, J D; Smith, H; David, A J

1988-01-01

268

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

PubMed Central

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

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

269

Snapshot of Vibrio parahaemolyticus densities in open and closed shellfish beds in Coastal South Carolina and Mississippi.  

PubMed

Vibrio parahaemolyticus is a Gram negative, halophilic bacterium that is ubiquitous in warm, tropical waters throughout the world. It is a major cause of seafood-associated gastroenteritis and is generally associated with consumption of raw or undercooked seafood, especially oysters. This study presents a snapshot of total V. parahaemolyticus densities in surface waters and shellstock American oysters (Crassostrea virginica) from open and closed shellfish harvesting areas, as well as "more rural areas" on two different US coasts, the Atlantic and the Gulf. Sampling was conducted from 2001 to 2003 at five sites near Charleston/Georgetown, SC and at four locations in the Gulfport/Pascagoula, MS area. V. parahaemolyticus numbers were determined by a direct plating method using an alkaline-phosphatase-labeled DNA probe targeting the species-specific thermolabile hemolysin gene (tlh) that was used for identification of bacterial isolates. The greatest difference between the two coasts was salinity; mean salinity in SC surface waters was 32.9 ppt, whereas the mean salinity in MS waters was 19.2 ppt, indicating more freshwater input into MS shellfish harvesting areas during the study period. The mean V. parahaemolyticus numbers in oysters were almost identical between the two states (567.4 vs. 560.1 CFU/g). Bacterial numbers in the majority of surface water samples from both states were at or below the limit of detection (LOD?=?<10 CFU/mL). The bacterial concentrations determined during this study predict a low public health risk from consumption of oysters in shellfish growing areas on either the Gulf or the Atlantic US coast. PMID:25106119

Moore, J Gooch; Ruple, A; Ballenger-Bass, K; Bell, S; Pennington, P L; Scott, G I

2014-11-01

270

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

NASA Astrophysics Data System (ADS)

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 others. This statistical underpinning can guide efforts to identify physical and/or biological mechanisms underlying the patterns revealed by the HAB Index. Although A. fundyense cyst survey data (limited to 9 years) do not span the entire interval of the shellfish toxicity records, this analysis leads us to hypothesize that major changes in the abundance of A. fundyense cysts may be a primary factor contributing to the decadal trends in shellfish toxicity in this region. The HAB Index approach taken here is simple but represents a novel and potentially useful tool for resource managers in many areas of the world subject to toxic HABs.

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

271

Suitability of postcolumn oxidation liquid chromatography method AOAC 2011.02 for monitoring paralytic shellfish toxins in Alaskan shellfish--initial pilot study versus mouse bioassay and in-house validation.  

PubMed

An in-house study was conducted to confirm the suitability of the postcolumn oxidation (PCOX) LC method, AOAC 2011.02, for regulatory monitoring of paralytic shellfish toxins (PSTs) in Alaskan shellfish. The following parameters were evaluated: calibration linearity, linear range, retention time stability, accuracy, repeatability, LOQ, and comparability with AOAC 959.08, the mouse bioassay (MBA) for PSTs. Mean recoveries for oyster homogenate spiked at 66 microg saxitoxin (STX) diHCI eq./100 g and 5 microg STX diHCI eq./100 g were 95 (n = 8) and 104%, respectively. Repeatability (n = 8) was 1.6 and 7% RSD, respectively. LOQ was estimated at 5 microg STX diHCl eq./100 g with S/N = 6 for STX. Comparability with the MBA was evaluated by duplicate analysis of regulatory samples using the original homogenate for both methods. Forty-one samples with MBA results varying between 40 and 500 microg STX diHCl eq./100 g were compared to corresponding PCOX values. The correlation coefficient (r2) = 0.96, with a slope of 2.1. The slope indicates an average 2X higher total toxicity result for PCOX versus MBA, a result that is consistent with prior literature showing low recoveries using the MBA. PMID:24830139

Hignutt, Emanuel

2014-01-01

272

Immunohistochemical localization and radioenzymatic measurements of serotonin (5-hydroxytryptamine) in hearts of Aplysia and several bivalve mollusks.  

PubMed

Serotonin immunoreactivity was localized in hearts of the opisthobranch gastropod, Aplysia californica (sea hare) and several species of bivalve mollusks, the heterodonts, Mercenaria mercenaria (quahog or cherry stone clam), Protothaca staminea (little neck clam), and the pteriomorphs, Hinnites multirugosus (rock scallop), Crassostrea virginica (eastern oyster), Mytilus edulis (eastern mussel), and Geukensia demissa (ribbed mussel). In addition, serotonin was assayed in the ventricles, auricles and heart-associated tissues in A. californica, M. mercenaria, H. multirugosus, and G. demissa with a sensitive radioenzymatic assay. Serotonin concentrations and the density of innervation were significantly higher in members of the subclass Heterodonta compared to the subclass Pteriomorpha. Serotonin immunoreactivity was observed in all species surveyed except G. demissa, which also contained relatively low concentrations of serotonin. Varicose fibers presumably corresponding to release sites were localized in the ventricles, auricles, and the auricular-ventricular valves. We hypothesize that in the species where serotonin-immunoreactive fibers are present, serotonin serves to modulate cardiac myogenic activity. The significance of the observed distribution and concentration of serotonin to the physiological effects of serotonin on cardiac function in these species is discussed. PMID:1423510

Ono, J K; Hampton, J D; Koch, R A

1992-09-01

273

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

PubMed Central

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 ?-glucuronidase and lysyl aminopeptidase activities for E. coli and Vibrionaceae, respectively. Cellulose membranes containing the substrates 4-methylumbeferyl-?-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

Richards, Gary P.; Watson, Michael A.

2010-01-01

274

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

PubMed

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

Richards, Gary P; Watson, Michael A

2010-01-01

275

Spatial distribution and multiannual trends of potentially toxic microalgae in shellfish farms along the Sardinian coast (NW Mediterranean Sea).  

PubMed

In this study, the geographical distribution and multiannual trends of potentially toxic harmful algal species (HAS) were analysed at 18 mussel farms in Sardinia (Italy, North-Western Mediterranean Sea) using data derived from the Sardinian Regional Monitoring Programme (1988-2012). The results showed an increasing number of potentially toxic microalgae over the study period. Alexandrium catenella and Alexandrium minutum were the most harmful species detected. From 2002 to 2009, these species caused eight paralytic shellfish poisoning-positive events which temporarily stopped commercial trade of mussels. The statistical analysis indicated that some taxa exhibited temporal increasing trends in their abundance (e.g. Pseudo-nitzschia spp.), significant decrements (e.g. Dinophysis sp.), or both increasing and decreasing significant trends (e.g. A. minutum) at different sites, indicating the necessity of further in-depth studies, especially on certain taxa. Overall, the statistical elaboration of the long-term data provided useful signals for early detection of shellfish contamination by different potentially toxic HAS in defined sites. These signals can be used to develop best management practices. PMID:25655125

Bazzoni, Anna Maria; Caddeo, Tiziana; Pulina, Silvia; Padedda, Bachisio M; Satta, Cecilia T; Sechi, Nicola; Lugliè, Antonella

2015-03-01

276

Relation of fish and shellfish distributions to habitat and water quality in the Mobile Bay estuary, USA.  

PubMed

The Mobile Bay estuary in the northern Gulf of Mexico provides a rich habitat for many fish and shellfish, including those identified as economically and ecologically important. The National Estuary Program in Mobile Bay has focused on restoration of degraded estuarine habitat on which these species depend. To support this effort, we used statistical techniques of ordination, cluster analysis, and discriminant analysis to relate distributions of individual fish and shellfish species and species assemblages to two dozen water quality and habitat variables in a geo-referenced database. Species appeared to respond to dominant gradients of low to high salinity and upland to offshore habitat area; many of the 15 communities identified via cluster analysis showed aggregated spatial distributions that could be related to habitat characteristics. Species in the Mobile River Delta were distinct from those in other areas of the estuary. This analysis supports habitat management in the Mobile Bay estuary; however, due to mobility of organisms among sampling locations and the dynamic environmental conditions in estuaries, we conclude that the analyses presented here are most appropriate for an evaluation of the estuary as a whole. PMID:19083112

Rashleigh, Brenda; Cyterski, Mike; Smith, Lisa M; Nestlerode, Janet A

2009-03-01

277

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

PubMed Central

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

Gobler, Christopher J.

2010-01-01

278

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

NASA Astrophysics Data System (ADS)

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 concentrations is adequate for first-order modeling of toxin kinetics in this species. Furthermore, the differential detoxification response of viscera and other tissues in relation to temperature emphasizes the need for two-compartment modeling to describe the fate of PSP toxins in this species. Finally, key parameters were identified that may prove useful in hindcasting the timing of toxic blooms or new toxin input in deep offshore waters where routine monitoring of toxic phytoplankton is impractical.

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

2014-05-01

279

[Modeling the occurrence of shellfish poisoning outbreaks caused by Gymnodinium catenatum (Dinophyceae) through electromagnetic signal triggering].  

PubMed

Accumulation of paralytic shellfish poisoning toxins (PSTs) in bivalves attributed to Gymnodinium catenatum blooms at the NW Portuguese coast was previously associated with periods of low solar activity (measured by the radio flux [R]), or low geomagnetic A(a) index. It was also observed that reduction of R preceded the occurrence of toxin accumulation, while A(a) index increase could be related to its absence during periods of low activity. For modeling toxin accumulation, the monthly decrease in R was studied along the decade 2003-2012. A match that helped explaining the highly toxic years of 2007 and 2008 was obtained by plotting the formula: ?R = (R(n-1) - R(n))/(R(n) - 65)2, where 65 represented the lowest radio activity known to date. The complex denominator was required to take into account the sunspot cycle. A 1-2 month lag was observed between maximal relative decline and maximal PSTs accumulation. PSTs in bivalves from the Portuguese south coast were related with natural electromagnetic cycles for the first time, and were not statistically associated with low R. A statistically significant association with low A(a) index also was not achieved, due to the low number of occurrences, although the 25-75 percentile was restricted to low Aa indexes in a similar way to that found for the NW coast. PSTs accumulation outside solar minima could be triggered by a steep decline in the A(a) index (?A), but no lag was observed in this case. While ?R amplitude helped explaining the highly toxic years of 2007 and 2008 at the NW coast, the amplitude of ?A was not related to the severity of the accumulation. Other kind of local electromagnetic signaling was investigated resorting to the occurrence of seismologic phenomena, because these events can trigger electric activities. No statistical association was found between seism number or magnitude and PSTs at the south coast, located near the boundary between the African and Eurasian plates, and marked by moderate seismicity. PMID:25715602

Vale, Pulo

2014-01-01

280

In silico analysis of putative paralytic shellfish poisoning toxins export proteins in cyanobacteria.  

PubMed

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 L(398)XGLQD(403) (SxtM) and L(390)VGLRD(395) (SxtF) in toxin recognition. PMID:23457475

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

2013-01-01

281

First evidence of “paralytic shellfish toxins” and cylindrospermopsin in a Mexican freshwater system, Lago Catemaco, and apparent bioaccumulation of the toxins in “tegogolo” snails ( Pomacea patula catemacensis)  

Microsoft Academic Search

Exposure to cyanobacterial toxins in freshwater systems, including both direct (e.g., drinking water) and indirect (e.g., bioaccumulation in food webs) routes, is emerging as a potentially significant threat to human health. We investigated cyanobacterial toxins, specifically cylindrospermopsin (CYN), the microcystins (MCYST) and the “paralytic shellfish toxins” (PST), in Lago Catemaco (Veracruz, Mexico). Lago Catemaco is a tropical lake dominated by

John P. Berry; Owen Lind

2010-01-01

282

Assessing and managing the health risk due to ingestion of inorganic arsenic from fish and shellfish farmed in blackfoot disease areas for general Taiwanese.  

PubMed

This paper assesses health risks due to the ingestion of inorganic arsenic from fish and shellfish farmed in blackfoot disease areas by general public in Taiwan. The provisional tolerable weekly intake of arsenic set by FAO/WHO and the target cancer risk assessment model proposed by USEPA were integrated to evaluate the acceptable consumption rate. Five aquacultural species, tilapia (Oreochromis mossambicus), milkfish (Chanos chanos), mullet (Mugil cephalus), clam (Meretrix lusoria) and oyster (Crassostrea gigas) were included. Monte Carlo analysis was used to propagate the parameter uncertainty and to probabilistically assess the health risk associated with the daily intake of inorganic As from farmed fish and shellfish. The integrated risk-based analysis indicates that the associated 50th and 95th percentile health risk are 2.06×10(-5) and 8.77×10(-5), respectively. Moreover, the acceptable intakes of inorganic As are defined and illustrated by a two dimensional graphical model. According to the relationship between C(inorg) and IR(f) derived from this study, two risk-based curves are constructed. An acceptable risk zone is determined (risk ranging from 1×10(-5) to 6.07×10(-5)) which is recommended for acceptable consumption rates of fish and shellfish. To manage the health risk due to the ingestion of inorganic As from fish and shellfish in BFD areas, a risk-based management scheme is derived which provide a convenient way for general public to self-determine the acceptable seafood consumption rate. PMID:21134715

Liang, Ching-Ping; Liu, Chen-Wuing; Jang, Cheng-Shin; Wang, Sheng-Wei; Lee, Jin-Jing

2011-02-15

283

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

PubMed Central

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

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

2015-01-01

284

Possible influence of natural events on heavy metals exposure from shellfish consumption: a case study in the north-East of Italy.  

PubMed

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

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

2015-01-01

285

Simultaneous presence of paralytic and diarrheic shellfish poisoning toxins in Mytilus chilensis samples collected in the Chiloe Island, Austral Chilean fjords.  

PubMed

The study shown here provides the first indisputable evidence that shellfish can be contaminated with Paralytic Shellfish Poisoning (PSP) and Diarrheic Shellfish Poisoning (DSP) toxins during the summer season in the Southern Chilean fjords. Quantitative analysis of the simultaneous presence of PSP and DSP toxins in Mytilus chilensis samples collected in the Chiloe Island are shown. The High Performance Liquid Chromatography (HPLC) analysis with pre-column derivatization method for DSP toxins and the post-column derivatization methods for PSP toxins, both with fluorescent on-line detections, showed that both type of toxins were concentrated by the filter bivalve Mytilus chilensis in amounts above the international safe limits. The phytoplankton analysis showed the presence of both Alexandrium catenella and Dinophysis acuta in the water column. The data shows stratification of the toxic dinoflagellates in the water column, since the lowest amount of both DSP and PSP toxins were measured in the superficial and deeper levels of the water column. Moreover, the highest toxicities of both types of toxins were shown by the shellfish samples collected at a depth of 6 meters with 190 nanograms of DTX-1 / gram of digestive gland and 709.8 microg of PSP toxins / 100 grams of mussel meat. PMID:15586821

Garcá, Carlos; Mardones, Pamela; Sfeir, Andrea; Lagos, Néstor

2004-01-01

286

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

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

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

2015-03-27

287

Detection of Diarrheic Shellfish Poisoning and Azaspiracid Toxins in Moroccan Mussels: Comparison of the LC-MS Method with the Commercial Immunoassay Kit  

PubMed Central

Diarrheic shellfish poisoning (DSP) is a recurrent gastrointestinal illness in Morocco, resulting from consumption of contaminated shellfish. In order to develop a rapid and reliable technique for toxins detection, we have compared the results obtained by a commercial immunoassay-“DSP-Check” kit” with those obtained by LC-MS. Both techniques are capable of detecting the toxins in the whole flesh extract which was subjected to prior alkaline hydrolysis in order to detect simultaneously the esterified and non esterified toxin forms. The LC-MS method was found to be able to detect a high level of okadaic acid (OA), low level of dinophysistoxin-2 (DTX2), and surprisingly, traces of azaspiracids 2 (AZA2) in mussels. This is the first report of a survey carried out for azaspiracid (AZP) contamination of shellfish harvested in the coastal areas of Morocco. The “DSP-Check” kit was found to detect quantitatively DSP toxins in all contaminated samples containing only OA, provided that the parent toxins were within the range of detection and was not in an ester form. A good correlation was observed between the two methods when appropriate dilutions were performed. The immunoassay kit appeared to be more sensitive, specific and faster than LC-MS for determination of DSP in total shellfish extract. PMID:19172196

Elgarch, Adra; Vale, Paulo; Rifai, Saida; Fassouane, Aziz

2008-01-01

288

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)

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 OMA 2011.27 [AOAC Official Method 2011.27 Paralytic Shellfish Toxins (PSTs) in Shellfish, Receptor Binding Assay. In Official Methods of Analysis of AOAC International ], further demonstrating successful extension of the LC-FD method to these clinical matrices. Moreover, data generated from this poisoning event reiterated that urine is a preferable clinical matrix, compared to serum, for diagnostic purposes due to higher accumulation and longer residence times in urine.

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

2014-05-01

289

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

PubMed

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:24007738

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

2013-12-01

290

Comparison of toxicity between saxitoxin and decarbamoyl saxitoxin in the mouse bioassay for paralytic shellfish poisoning toxins.  

PubMed

The mouse bioassay (MBA) for paralytic shellfish poisoning (PSP) toxins has been used in the AOAC Official Method and the official Japanese method. In the AOAC Official Method, the saxitoxin (STX) standard provided by the U.S. Food and Drug Administration (FDA) is used, but no standard is used in the official Japanese method. The objective of this study was to compare the toxicity of decarbamoyl STX (dcSTX), one of the derivatives of STX and a candidate standard for the MBA for PSP toxins in Japan, to that of FDA STX in the MBA platform. In this study, the toxicity of dcSTX was 918.0 ± 44.9 mouse units/µmol, and the relative toxicity ratio of dcSTX to FDA STX based on moles was 0.478. PMID:25213205

Suzuki, Hodaka; Machii, Kenji

2014-11-01

291

Comparison of Toxicity between Saxitoxin and Decarbamoyl Saxitoxin in the Mouse Bioassay for Paralytic Shellfish Poisoning Toxins  

PubMed Central

ABSTRACT The mouse bioassay (MBA) for paralytic shellfish poisoning (PSP) toxins has been used in the AOAC Official Method and the official Japanese method. In the AOAC Official Method, the saxitoxin (STX) standard provided by the U.S. Food and Drug Administration (FDA) is used, but no standard is used in the official Japanese method. The objective of this study was to compare the toxicity of decarbamoyl STX (dcSTX), one of the derivatives of STX and a candidate standard for the MBA for PSP toxins in Japan, to that of FDA STX in the MBA platform. In this study, the toxicity of dcSTX was 918.0 ± 44.9 mouse units/µmol, and the relative toxicity ratio of dcSTX to FDA STX based on moles was 0.478. PMID:25213205

SUZUKI, Hodaka; MACHII, Kenji

2014-01-01

292

Development of a colony hybridization method for the enumeration of total and potentially enteropathogenic Vibrio parahaemolyticus in shellfish.  

PubMed

Vibrio parahaemolyticus is a marine microorganism, recognized as cause of gastroenteritis outbreaks associated with seafood consumption. In this study the development and the in-house validation of a colony hybridization method for the enumeration of total and potentially pathogenic V. parahaemolyticus is reported. The method included a set of three controls (process, hybridization and detection control) for the full monitoring of the analytical procedure. Four digoxigenin-labeled probes were designed for pathogenic strains enumeration (tdh1, tdh2, trh1 and trh2 probes) and one for total V. parahaemolyticus count (toxR probe). Probes were tested on a panel of 70 reference strains and 356 environmental, food and clinical isolates, determining the inclusivity (tdh: 96.7%, trh: 97.8%, toxR: 99.4%) and the exclusivity (100% for all probes). Accuracy and linearity of the enumeration were evaluated on pure and mixed cultures: slopes of the regression lines ranged from 0.957 to 1.058 depending on the target gene and R(2) was greater than or equal to 0.989 for all reactions. Evaluation was also carried on using four experimentally contaminated seafood matrices (shellfish, finfish, crustaceans and cephalopods) and the slopes of the curves varied from 0.895 (finfish) to 0.987 (cephalopods) for the counts of potentially pathogenic V. parahaemolyticus (R(2)?0.965) and from 0.965 to 1.073 for total V. parahaemolyticus enumeration (R(2)?0.981). Validation was performed on 104 naturally contaminated shellfish samples, analyzed in parallel by colony hybridization, ISO/TS 21872-1 and MPN enumeration. Colony hybridization and ISO method showed a relative accuracy of 86.7%, and a statistically significant correlation was present between colony hybridization enumeration and MPN results (r=0.744, p<0.001). The proposed colony hybridization can be a suitable alternative method for the enumeration of total and potentially pathogenic V. parahaemolyticus in seafood. PMID:24984219

Suffredini, Elisabetta; Cozzi, Loredana; Ciccaglioni, Gianni; Croci, Luciana

2014-09-01

293

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

PubMed Central

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, ? ? 3/? ? 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ? ? 3/? ? 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ? ? 3/? ? 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

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

2013-01-01

294

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

PubMed

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, ? - 3/? - 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ? - 3/? - 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ? - 3/? - 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

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

2013-01-01

295

Rapid and Sensitive Detection of Noroviruses by Using TaqMan-Based One-Step Reverse Transcription-PCR Assays and Application to Naturally Contaminated Shellfish Samples  

Microsoft Academic Search

Noroviruses (NoV), which are members of the family Caliciviridae, are the most important cause of outbreaks of acute gastroenteritis worldwide and are commonly found in shellfish grown in polluted waters. In the present study, we developed broadly reactive one-step TaqMan reverse transcription (RT)-PCR assays for the detection of genogroup I (GI) and GII NoV in fecal samples, as well as

Narayanan Jothikumar; James A. Lowther; Kathleen Henshilwood; David N. Lees; Vincent R. Hill; Jan Vinje

2005-01-01

296

Simultaneous determination of 2-naphthol and 1-hydroxypyrene in fish and shellfish contaminated with crude oil by gas chromatography-mass spectrometry.  

PubMed

This paper describes a gas chromatography-mass spectrometric method of l-hydroxypyrene (1-HOP) and 2-naphthol (2-NAP) in fish and shellfish. Alkali hydrolysis method in this study was chosen and optimized to the reaction condition for 90 min at 90°C in a 2.0M KOH solution. For five independent determinations at 0.2 and 1.0 ?g/kg, the coefficient of variation was less than 5.1%. This method was used to assess the long-term influence of spilled crude oil on marine ecosystems and analyze fifty-two shellfish samples taken in the near of the accident region of the Hebei Spirit oil spill. 2-NAP and 1-HOP were detected in the mean concentration range of 0.09-12.42 and 0.03-0.06 ?g/kg, respectively. 2-NAP was detected in a high concentration range in shellfishes gathered in 2 months after the accident and it decreased rapidly to 6 months after that. The results showed that 2-NAP might be an important biomarker in biota contaminated with crude oil. PMID:23411178

Lim, Hyun-Hee; Shin, Ho-Sang

2013-06-01

297

Rapid and Efficient Extraction Method for Reverse Transcription-PCR Detection of Hepatitis A and Norwalk-Like Viruses in Shellfish  

PubMed Central

As part of an effort to develop a broadly applicable test for Norwalk-like viruses and hepatitis A virus (HAV) in shellfish, a rapid extraction method that is suitable for use with one-step reverse transcription (RT)-PCR-based detection methods was developed. The method involves virus extraction using a pH 9.5 glycine buffer, polyethylene glycol (PEG) precipitation, Tri-reagent, and purification of viral poly(A) RNA by using magnetic poly(dT) beads. This glycine–PEG–Tri-reagent–poly(dT) method can be performed in less than 8 h on hard-shell clams (Mercenaria mercenaria) and Eastern oysters (Crassostrea virginica) and, when coupled with RT-PCR-based detection, can yield results within 24 h. Observed sensitivities for seeded shellfish extracts are as low as 0.015 PFU of HAV and 22.4 RT-PCR50 units for Norwalk virus. Detection of HAV in live oysters experimentally exposed to contaminated seawater is also demonstrated. An adaptation of this method was used to identify HAV in imported clams (tentatively identified as Ruditapes philippinarum) implicated in an outbreak of food-borne viral illness. All of the required reagents are commercially available. This method should facilitate the implementation of RT-PCR testing of commercial shellfish. PMID:11526018

Kingsley, David H.; Richards, Gary P.

2001-01-01

298

[Training for female shellfish gatherers on food safety and worker's health: an experience in the community of Ilha do Paty, Brazil].  

PubMed

This study describes an experience in the training of female shellfish gatherers in the fishing community in Ilha do Paty, São Francisco do Conde, within the context of actions to promote health and food safety. This is an intervention study with planning of activities by a multidisciplinary team. The activities were developed in five stages: survey of topics of interest; awareness; female shellfish gatherers' work routine; teaching of best practices in the processing of shellfish; and group conversation. The methodologies included exposure through dialogue, group dynamics, workshops, theater, work with images, directed activities and the distribution of educational materials. At the end, an evaluation by the participants regarding the different aspects was conducted. Overall there was satisfaction among the audience for most indicators, which may relate to both the use of audiovisual resources and strategies that permitted the exchange of experiences regarding the recognition of the importance of training by the target audience. The experiment demonstrates the potential of developing educational activities with the fishing communities, with results that contribute to the bolstering of the local supply chain, with the promotion of food safety and occupational health. PMID:24897221

da Nóbrega, Gabriela Silva; Cardoso, Ryzia de Cassia Vieira; Furtunato, Dalva Maria da Nóbrega; Góes, José Ângelo Wenceslau; Ferreira, Tereza Cristina Braga; Santos, Mary Daiane Fontes; Santos, Sissa Maria Garrido

2014-05-01

299

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

PubMed

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 following incubation of incurred homogenates with optimum proportions of surf clam tissue, resulting in materials containing a large number of PSP toxins. Stability experiments provided good preliminary evidence for the stability of these targeted materials under storage conditions. The work therefore provides both additional information relating to the transformational activity in UK surf clams and highlights a good potential method for the targeted production of reference materials which include a wider range of toxins than normally present in naturally incurred shellfish. PMID:23369833

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

2013-04-01

300

Immunoassay of paralytic shellfish toxins by moving magnetic particles in a stationary liquid-phase lab-on-a-chip.  

PubMed

In this study, we devised a stationary liquid-phase lab-on-a-chip (SLP LOC), which was operated by moving solid-phase magnetic particles in the stationary liquid phase. The SLP LOC consisted of a sample chamber to which a sample and reactants were added, a detection chamber containing enzyme substrate solution, and a narrow channel connecting the two chambers and filled with buffer. As a model system, competitive immunoassays of saxitoxin (STX), a paralytic shellfish toxin, were conducted in the SLP LOC using protein G-coupled magnetic particles (G-MPs) as the solid phase. Anti-STX antibodies, STX-horseradish peroxidase conjugate, G-MPs, and a STX sample were added to the sample chamber and reacted by shaking. While liquids were in the stationary state, G-MPs were transported from the sample chamber to the detection chamber by moving a magnet below the LOC. After incubation to allow the enzymatic reaction to occur, the absorbance of the detection chamber solution was found to be reciprocally related to the STX concentration of the sample. Thus, the SLP LOC may represent a novel, simple format for point-of-care testing applications of enzyme-linked immunosorbent assays by eliminating complicated liquid handling steps. PMID:25460894

Kim, Myoung-Ho; Choi, Suk-Jung

2015-04-15

301

Future Oceanic Warming and Acidification Alter Immune Response and Disease Status in a Commercial Shellfish Species, Mytilus edulis L.  

PubMed Central

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

Mackenzie, Clara L.; Lynch, Sharon A.; Culloty, Sarah C.; Malham, Shelagh K.

2014-01-01

302

Paralytic shellfish toxins in the chocolata clam, Megapitaria squalida (Bivalvia: Veneridae), in Bahía de La Paz, Gulf of California.  

PubMed

Occurrence and toxic profiles of paralytic shellfish toxins (PST) in the chocolata clam Megapitaria squalida were investigated. From December 2001 to December 2002, 25 clams were obtained monthly from Bahia de La Paz, Gulf of California. Additionally, net (20 microm) and bottle phytoplankton samples were also collected to identify toxic species. Toxins were analyzed by HPLC with post-column oxidation and fluorescence detection. Toxicity in the clam was low and varied from 0.14 to 5.46 microg/STXeq/100 g. Toxicity was detected in December, March, April, June, and August. Toxin profile was composed mainly by STX, GTX2, GTX3, dcGTX2, dcGTX3, C2, dcSTX and B1. Gymnodinium catenatum was the only PST-producing dinoflagellate identified in the phytoplankton samples throughout the study period. G. catenatum was observed mainly in net samples from December 2001 to December 2002; however, in bottle samples, G. catenatum was only observed in five months. Highest abundance (2600 cells l(-1)) was observed in March and the lowest (160 cells l(-1)) in June. G. catenatum mainly formed two-cell chains and rarely four or eight. The presence of PST in net phytoplankton samples support the fact that G. catenatum is the main source of PST in the clams. This study represents the first report of PST toxins in the chocolata clam from Bahia de La Paz. PMID:17465127

Gárate-Lizárraga, I; Bustillos-Guzmán, J J; Erler, K; Muñetón-Gómez, M S; Luckas, B; Tripp-Quezada, A

2004-09-01

303

Paralytic shellfish poisoning (PSP) toxin binders for optical biosensor technology: problems and possibilities for the future: a review  

PubMed Central

This review examines the developments in optical biosensor technology, which uses the phenomenon of surface plasmon resonance, for the detection of paralytic shellfish poisoning (PSP) toxins. Optical biosensor technology measures the competitive biomolecular interaction of a specific biological recognition element or binder with a target toxin immobilised onto a sensor chip surface against toxin in a sample. Different binders such as receptors and antibodies previously employed in functional and immunological assays have been assessed. Highlighted are the difficulties in detecting this range of low molecular weight toxins, with analogues differing at four chemical substitution sites, using a single binder. The complications that arise with the toxicity factors of each toxin relative to the parent compound, saxitoxin, for the measurement of total toxicity relative to the mouse bioassay are also considered. For antibodies, the cross-reactivity profile does not always correlate to toxic potency, but rather to the toxin structure to which it was produced. Restrictions and availability of the toxins makes alternative chemical strategies for the synthesis of protein conjugate derivatives for antibody production a difficult task. However, when two antibodies with different cross-reactivity profiles are employed, with a toxin chip surface generic to both antibodies, it was demonstrated that the cross-reactivity profile of each could be combined into a single-assay format. Difficulties with receptors for optical biosensor analysis of low molecular weight compounds are discussed, as are the potential of alternative non-antibody-based binders for future assay development in this area. PMID:21623494

Campbell, K.; Rawn, D.F.K.; Niedzwiadek, B.; Elliott, C.T.

2011-01-01

304

Persicobacter psychrovividus sp. nov., isolated from shellfish, and emended descriptions of the genus Persicobacter and Persicobacter diffluens.  

PubMed

The taxonomic position of three bacterial strains, Asr22-19T, NBRC 101035 and NBRC 101041, isolated from shellfish in Japan, was determined by using a polyphasic taxonomic approach. The strains were facultatively anaerobic, motile by gliding and Gram-staining-negative slender rods. Their major respiratory quinone was menaquinone-7 and their predominant cellular fatty acids were iso-C15:0, iso-C17:0 3-OH, iso-C15:0 3-OH, C16:0 3-OH, and C16:0. The G+C content of the genomic DNA was 42.0-42.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains clustered with the genus Persicobacter in the family 'Flammeovirgaceae'. DNA-DNA relatedness values were higher than 68% among strains Asr22-19T, NBRC 101035 and NBRC 101041, and were lower than 28% between strain Asr22-19T and Persicobacter diffluens NBRC 15940T. The three novel strains could be differentiated from Persicobacter diffluens by several phenotypic characteristics. On the basis of these results, the novel species Persicobacter psychrovividus sp. nov. (type strain Asr22-19T=NBRC 101262T=CIP 109100T) is proposed and emended descriptions are given for the genus Persicobacter and for Persicobacter diffluens. PMID:19734280

Muramatsu, Yuki; Takahashi, Mai; Kaneyasu, Mika; Iino, Takao; Suzuki, Ken-ichiro; Nakagawa, Yasuyoshi

2010-08-01

305

Multiple stable isotopes used to trace the flow of organic matter in estuarine food webs.  

PubMed

The use of a combination of the stable isotopes of sulfur, carbon, and nitrogen allows the flow of organic matter and trophic relations in salt marshes and estuaries to be traced while eliminating many ambiguities that accompany the use of a single isotopic tracer. Salt-marsh grasses take up the isotopically light sulfides formed during sulfate reduction, and the transfer of this light sulfur through the marsh food web is illustrated with data on the ribbed mussel (Geukensia demissa) from various locations in a New England marsh. The multiple isotope approach shows that this filter feeder consumes both marsh grass ( Spartina) detritus and plankton, with the relative proportions of each determined by the location of the mussels in the marsh. PMID:17793771

Peterson, B J; Howarth, R W; Garritt, R H

1985-03-15

306

Multiple Stable Isotopes Used to Trace the Flow of Organic Matter in Estuarine Food Webs  

NASA Astrophysics Data System (ADS)

The use of a combination of the stable isotopes of sulfur, carbon, and nitrogen allows the flow of organic matter and trophic relations in salt marshes and estuaries to be traced while eliminating many ambiguities that accompany the use of a single isotopic tracer. Salt-marsh grasses take up the isotopically light sulfides formed during sulfate reduction, and the transfer of this light sulfur through the marsh food web is illustrated with data on the ribbed mussel (Geukensia demissa) from various locations in a New England marsh. The multiple isotope approach shows that this filter feeder consumes both marsh grass (Spartina) detritus and plankton, with the relative proportions of each determined by the location of the mussels in the marsh.

Peterson, Bruce J.; Howarth, Robert W.; Garritt, Robert H.

1985-03-01

307

Minimal incorporation of Deepwater Horizon oil by estuarine filter feeders.  

PubMed

Natural abundance carbon isotope analyses are sensitive tracers for fates and use of oil in aquatic environments. Use of oil carbon in estuarine food webs should lead to isotope values approaching those of oil itself, -27‰ for stable carbon isotopes reflecting oil origins and -1000‰ for carbon-14 reflecting oil age. To test for transfer of oil from the 2010 Deepwater Horizon spill into estuarine food webs, filter-feeding barnacles (Balanus sp.) and marsh mussels (Geukensia demissa) were collected from Louisiana estuaries near the site of the oil spill. Carbon-14 analyses of these animals from open waters and oiled marshes showed that oil use was <1% and near detection limits estimated at 0.3% oil incorporation. Respiration studies showed no evidence for enhanced microbial activity in bay waters. Results are consistent with low dietary impacts of oil for filter feeders and little overall impact on respiration in the productive Louisiana estuarine systems. PMID:24461698

Fry, Brian; Anderson, Laurie C

2014-03-15

308

Uptake, distribution and depuration of paralytic shellfish toxins from Alexandrium minutum in Australian greenlip abalone, Haliotis laevigata.  

PubMed

Farmed greenlip abalone Haliotis laevigata were fed commercial seaweed-based food pellets or feed pellets supplemented with 8 × 10? Alexandrium minutum dinoflagellate cells g?¹ (containing 12 ± 3.0 ?g STX-equivalent 100 g?¹, which was mainly GTX-1,4) every second day for 50 days. Exposure of abalone to PST supplemented feed for 50 days did not affect behaviour or survival but saw accumulation of up to 1.6 ?g STX-equivalent 100 g?¹ in the abalone foot tissue (muscle, mouth without oesophagus and epipodial fringe), which is ?50 times lower than the maximum permissible limit (80 ?g 100 g?¹ tissue) for PSTs in molluscan shellfish. The PST levels in the foot were reduced to 0.48 ?g STX-equivalent 100 g?¹ after scrubbing and removal of the pigment surrounding the epithelium of the epipodial fringe (confirmed by both HPLC and LC-MS/MS). Thus, scrubbing the epipodial fringe, a common procedure during commercial abalone canning, reduced PST levels by ?70%. Only trace levels of PSTs were detected in the viscera (stomach, gut, heart, gonad, gills and mantle) of the abalone. A toxin reduction of approximately 73% was observed in STX-contaminated abalone held in clean water and fed uncontaminated food over 50 days. The low level of PST uptake when abalone were exposed to high numbers of A. minutum cells over a prolonged period may indicate a low risk of PSP poisoning to humans from the consumption of H. laevigata that has been exposed to a bloom of potentially toxic A. minutum in Australia. Further research is required to establish if non-dietary accumulation can result in significant levels of PSTs in abalone. PMID:21640130

Dowsett, Natalie; Hallegraeff, Gustaaf; van Ruth, Paul; van Ginkel, Roel; McNabb, Paul; Hay, Brenda; O'Connor, Wayne; Kiermeier, Andreas; Deveney, Marty; McLeod, Catherine

2011-07-01

309

Impact of elevated pCO? on paralytic shellfish poisoning toxin content and composition in Alexandrium tamarense.  

PubMed

Ocean acidification is considered a major threat to marine ecosystems and may particularly affect primary producers. Here we investigated the impact of elevated pCO? on paralytic shellfish poisoning toxin (PST) content and composition in two strains of Alexandrium tamarense, Alex5 and Alex2. Experiments were carried out as dilute batch to keep carbonate chemistry unaltered over time. We observed only minor changes with respect to growth and elemental composition in response to elevated pCO?. For both strains, the cellular PST content, and in particular the associated cellular toxicity, was lower in the high CO? treatments. In addition, Alex5 showed a shift in its PST composition from a non-sulfated analogue towards less toxic sulfated analogues with increasing pCO?. Transcriptomic analyses suggest that the ability of A. tamarense to maintain cellular homeostasis is predominantly regulated on the post-translational level rather than on the transcriptomic level. Furthermore, genes associated to secondary metabolite and amino acid metabolism in Alex5 were down-regulated in the high CO? treatment, which may explain the lower PST content. Elevated pCO? also induced up-regulation of a putative sulfotransferase sxtN homologue and a substantial down-regulation of several sulfatases. Such changes in sulfur metabolism may explain the shift in PST composition towards more sulfated analogues. All in all, our results indicate that elevated pCO? will have minor consequences for growth and elemental composition, but may potentially reduce the cellular toxicity of A. tamarense. PMID:24291633

Van de Waal, Dedmer B; Eberlein, Tim; John, Uwe; Wohlrab, Sylke; Rost, Björn

2014-02-01

310

Amnesic shellfish poisoning biotoxin detection in seawater using pure or amino-functionalized Ag nanoparticles and SERS.  

PubMed

Domoic acid (DA) biotoxin responsible for the amnesic shellfish poisoning (ASP) has been unambiguously detected in seawater in a broad range of concentration, with both pure and amino-functionalized Ag nanoparticles employed for surface enhanced Raman scattering (SERS). To achieve this, a comprehensive SERS study on DA dissolved in distilled water has been conducted. SERS of DA dissolved in seawater in concentrations ranging from 3.3 × 10(-4) to 3.3 × 10(-8) mol l(-1) exhibited specific signal, completely different to those of the corresponding DA aqueous solutions, due to the seawater interference in the overall SERS effect. In order to assess the capability of the technique as a cheaper alternative for rapid and unambiguous detection of the DA biotoxin in seawater, three detection schemes have been proposed. DA was detectable at 0.33 nmoll(-1) concentration (0.33) dissolved in distilled water and 0.033 nmol l(-1) (0.033 ppb) in seawater respectively, much lower than the admitted level by the current regulation. A solvent specific interaction of DA with the NPs was concluded, since DA aqueous solution added to Ag nanoparticles provided different SERS signal compared to that of DA directly dissolved in seawater. Employing amino-functionalized Ag nanoparticles with 4-aminothiophenol as SERS tag, SERS signal of DA on amino-AgNPs revealed significant specificity associated with the aromatic primary amine interaction of the SERS tag with DA, thus allowing DA detection in seawater at 4.16 × 10(-4) mol l(-1) concentration, much higher than in the case of pure NPs. To highlight the findings, a brief literature review to date on the DA biotoxin detection was also provided. PMID:25159386

Müller, Csilla; Glamuzina, Branko; Pozniak, Iva; Weber, Karina; Cialla, Dana; Popp, Jürgen; Cînt? Pînzaru, Simona

2014-12-01

311

The uptake, distribution and elimination of paralytic shellfish toxins in mussels and fish exposed to toxic dinoflagellates.  

PubMed

We exposed green-lipped mussels Perna viridis and black sea breams Acanthopagrus schlegeli to toxic dinoflagellates Alexandrium fundyense to evaluate the accumulation, distribution, transformation, and elimination of paralytic shellfish toxins (PSTs) in a controlled environmental condition. The mussels were fed A. fundyense for 7 days followed by 3 weeks of depuration, and the fish were fed toxic clams (pre-exposed to the dinoflagellates) for 5 days followed by 2 weeks of depuration. The toxin content and the compartmental distribution of PSTs were monitored throughout the experiments by high-performance liquid chromatography with post-column fluorescence derivatization (HPLC-FLD). This is the first report to assess the biokinetics of PSTs in marine fish under dietary exposure. The hepatopancreas in the mussels and the viscera in the fish accumulated most of the PSTs. Differential elimination of each toxin was observed in the mussels. The C2 toxins were eliminated rapidly in all organs; except in hepatopancreas, the more potent toxins such as GTX4, were eliminated slower during the depuration period. The relative proportions of various PSTs in the mussels changed over time, suggesting toxin-specific uptake and elimination rates, or biotransformation preferences between toxins. In the fish, the ratio of C1/C2 was 3.0 times (p<0.01) higher when compared to the clam tissues, indicating that conversion from C2 to C1 might have occurred when the toxin was transferred from the clams to the fish. In summary, species differences in uptake, distribution and elimination of PSTs were observed between mussels and fish, and this may influence trophic transfer of algal toxins in marine organisms. PMID:16959334

Kwong, Raymond W M; Wang, Wen-Xiong; Lam, Paul K S; Yu, Peter K N

2006-10-25

312

Assessment of a semiquantitative liquid chromatography-fluorescence detection method for the determination of paralytic shellfish poisoning toxin levels in bivalve molluscs from Great Britain.  

PubMed

AOAC Official Method 2005.06 precolumn oxidation LC-fluorescence detection method has been used for many years for the detection and quantitation of paralytic shellfish poisoning (PSP) toxins in bivalve molluscs. After extensive single- and multiple-laboratory validation, the method has been slowly gaining acceptance worldwide as a useful and practical tool for official control testing. In Great Britain, the method has become routine since 2008, with no requirement since then for reverting back to the bioassay reference method. Although the method has been refined to be semiautomated, faster, and more reproducible, the quantitation step can be complex and time-consuming. An alternative approach was developed to utilize the qualitative screening results for generating a semiquantitative results assessment. Data obtained over 5 years enabled the comparison of semiquantitative and fully quantitative PSP results in over 15 000 shellfish samples comprising eight different species showed that the semiquantitative approach resulted in over-estimated paralytic shellfish toxin levels by an average factor close to two in comparison with the fully quantified levels. No temporal trends were observed in the data or relating to species type, with the exception of surf clams. The comparison suggested a semiquantitative threshold of 800 microg saxitoxin (STX) eq/kg should provide a safe limit for the determination of samples to be forwarded to full quantitation. However, the decision was taken to halve this limit to include an additional safety factor of 2, resulting in the use of a semiquantitative threshold of 400 microg STX eq/kg. Implementation of the semiquantitative method into routine testing would result in a significant reduction in the numbers of samples requiring quantitation and have a positive impact on the overall turnaround of reported PSP results. The refined method would be appropriate for any monitoring laboratory faced with high throughput requirements. PMID:24830161

Turner, Andrew D; Dhanji-Rapkova, Monika; Baker, Clothilde; Algoet, Myriam

2014-01-01

313

Confirmation of brevetoxin metabolism in cockle, Austrovenus stutchburyi, and greenshell mussel, Perna canaliculus, associated with New Zealand neurotoxic shellfish poisoning, by controlled exposure to Karenia brevis culture.  

PubMed

We examined metabolism of PbTxs in New Zealand cockle, Austrovenus (A.) stutchburyi, and greenshell mussel, Perna (P.) canaliculus, by means of liquid chromatography coupled with tandem mass spectrometry. PbTx-2, PbTx-3 and BTX-B5 were detected in Karenia (K.) brevis culture medium in the ratio of ca. 50:2:5. The amounts of PbTx-3 and BTX-B5 were greatly increased in both seawater and shellfish exposed to K. brevis cultures or supernatant prepared by disruption of K. brevis under appropriate condition, while those of PbTx-2 were decreased. Some PbTx-2 was present in P. canaliculus, but not in A. stutchburyi. Low levels of BTX-B1 were detected in A. stutchburyi, but not P. canaliculus. Levels of PbTx-3 and BTX-B5 were highest immediately after exposure and then declined rapidly in both shellfish. BTX-B1 increased in concentration after exposure, and was then gradually eliminated from A. stutchburyi. Three successive exposures of A. stutchburyi to K. brevis cultures resulted in similar initial levels of PbTx-3 and BTX-B5, while BTX-B1 accumulated after each dose. In P. canaliculus, initial levels of PbTx-3 were similar, while PbTx-2 and BTX-B5 accumulated after each dose. PbTx-3 and BTX-B5 are proposed to be suitable markers for monitoring shellfish toxicity after a red tide event. PMID:15109891

Ishida, Hitoshi; Nozawa, Akira; Nukaya, Haruo; Rhodes, Lesley; McNabb, Paul; Holland, Patrick T; Tsuji, Kuniro

2004-05-01

314

Radioactive contamination of fish, shellfish, and waterfowl exposed to Hanford effluents: Annual summaries, 1945--1972. Hanford Environmental Dose Reconstruction Project  

SciTech Connect

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.

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

1992-07-01

315

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

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…

Florida State Univ., Tallahassee. Center for Studies in Vocational Education.

316

Introduction to Fish and Shellfish. Learning Activity Pack and Instructor's Guide 5.13a. Commercial Foods and Culinary Arts Competency-Based Series. Section 5: Basic Food Preparation.  

ERIC Educational Resources Information Center

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 fish and shellfish for restaurant use. Illustrated information sheets and learning activities are provided in these areas: buying and storing fish and…

Florida State Univ., Tallahassee. Center for Studies in Vocational Education.

317

Stimulation of wild strawberry ( Fragaria vesca) arbuscular mycorrhizas by addition of shellfish waste to the growth substrate: interaction between mycorrhization, substrate amendment and susceptibility to red core ( Phytophthora fragariae)  

Microsoft Academic Search

Wild strawberry (Fragaria vesca) microplants were inoculated at establishment in the glasshouse with the commercial inoculants Endorize IV, Vaminoc and Glomus mosseae. After 2 weeks, plants were transferred to control peat-based growth substrate and Suppressor®, a commercial peat substrate amended with chitin-containing shellfish waste. Percentage root length colonisation (%RLC) by Vaminoc and G. mosseae, but not Endorize IV, was stimulated

John G. Murphy; Susan M. Rafferty; Alan C. Cassells

2000-01-01

318

Inorganic carbon dynamics in the upwelling system off the Oregon coast and implications for commercial shellfish hatcheries  

NASA Astrophysics Data System (ADS)

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 (?) 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 ? 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 periods of low wind stress ranges from 100-700µatm. When strong equatorward winds induce upwelling, pCO2 levels exhibit a higher daily range of 300-2000µatm. The saturation state was calculated from the pCO2/TCO2 measurements of the discrete samples. The ? for calcite and aragonite ranged from 2.07 and 1.15 to 8.58 and 4.69 respectively from April through August. Increased pCO2 and decreased pH have been shown to negatively impact larval development in C. gigas (Kurihara, 2007). Periods of elevated pCO2 in May and June 2010 correlated with commercial losses at WCH. The use of precise pCO2 measurements in real time has proven to be a valuable tool for use in aquaculture. As a commercial practice WCH has elected to only use source water that is below empirical pCO2 thresholds for spawning and culturing larvae. This has resulted in continued production and cost saving in an industry crucial to coast economies. A continuous TCO2/pCO2 monitoring system will be integrated into this long time-series to constrain inorganic carbon providing insight into carbonate chemistry dynamics in Netarts Bay, effects of ocean acidification on bivalve development and possible water treatment approaches for commercial aquaculture.

Vance, J. M.; Hales, B. R.

2010-12-01

319

Effect of UV Light on the Inactivation of Recombinant Human Adenovirus and Murine Norovirus Seeded in Seawater in Shellfish Depuration Tanks.  

PubMed

Shellfish depuration is a process that aims to eliminate pathogens from mollusk tissues. Seawater disinfection during the depuration process is important and ultraviolet (UV) light treatment is the most used method worldwide. Viral models are usually employed as surrogates of fastidious viruses in viability studies. The aim of this study was to employ methods based on green fluorescent protein (GFP) fluorescence and plaque forming units to detect, respectively, recombinant adenovirus (rAdV-GFP) and murine norovirus (MNV) artificially seeded in environmental matrices. These assays were applied to assess the inactivation of rAdV-GFP and MNV in seawater in recirculation shellfish depuration tanks with and without UV light treatment. Kinetics of rAdV GFP-expression was previously measured by UV-spectrophotometer. Flow cytometry (FC), fluorescence microscopy (FM), and plaque assay were used to determine virus titer and detection limits. The influence of the environmental matrix on the performance of the methods was prior determined using either drinking water or filtered seawater seeded with rAdV-GFP. Disinfection of seeded seawater was evaluated with and without UV treatment. The time of 24-h post-infection was established as ideal for fluorescence detection on rAdV-GFP infected cells. FC showed lower sensitivity, when compared to FM, which was similar to plaque assay. Seawater disinfection on depuration tanks was promising and rAdV-GFP declined 99.99 % after 24 and 48 h with and without UV treatment, respectively. MNV was completely inactivated after 24 h in both treatments. As conclusion, the depuration tanks were effective to inactivate rAdV-GFP and MNV and the UV disinfection treatment accelerated the process. PMID:25528135

Garcia, Lucas A T; Nascimento, Mariana A; Barardi, Célia R M

2015-03-01

320

Transcriptional responses of xenobiotic metabolizing enzymes, HSP70 and Na+/K+ -ATPase in the liver of rabbitfish (Siganus oramin) intracoelomically injected with amnesic shellfish poisoning toxin.  

PubMed

Amnesic shellfish poisoning toxin domoic acid (DA) is a marine neurotoxin that accumulates in fish and shellfish, and has been implicated to be involved in human and marine wildlife mortality. The transcriptional responses of cytochrome P-450 1A (CYP1A), glutathione S-transferase alpha (GSTA), glutathione S-transferase rho (GSTR), heat shock protein 70 (HSP70), and Na(+)/K(+)-ATPase alpha 1 (ATP1A1) in the liver of rabbitfish (Siganus oramin) intracoelomically injected with DA, were investigated. Experimental fish were administered with one injection of DA (2 microg/g wet weight) or PBS as control. After 24 h, fish were killed and hepatic RNA was isolated. Partial cDNA of rabbitfish CYP1A, GSTA, GSTR, HSP70, ATP1A1, and beta-actin were obtained by PCR using degenerate primers. Using beta-actin as an external control, the relative liver CYP1A, GSTA, GSTR, HSP70, and ATP1A1 mRNA abundance of rabbitfish were determined by semi-quantitative RT-PCR within the exponential phase. The ratio CYP1A/beta-actin mRNA (%) of exposure group was determined to be 148.92+/-12.69, whereas the ratio of control group was 82.3+/-8.35, indicating that CYP1A was induced significantly in rabbitfish following DA exposure (P<0.05). Although the expressions of GSTA, HSP70, and ATP1A1 tended to increase and GSTR tended to decrease, no significant changes were found (P>0.05). The induction of hepatic CYP1A in response to DA suggests a potential role for fish phase I xenobiotic metabolizing enzyme in DA metabolism. PMID:18214893

Wang, Lin; Liang, Xu-Fang; Huang, Yan; Li, Shi-Ying; Ip, Kok-Chao

2008-06-01

321

Comparative analyses by HPLC and the sodium channel and saxiphilin 3H-saxitoxin receptor assays for paralytic shellfish toxins in crustaceans and molluscs from tropical North West Australia  

Microsoft Academic Search

The increased frequency and distribution of red tides requires the development of high-throughput detection methods for paralytic shellfish toxins (PST). Community ethics also requires that there be a reduced reliance upon the standard mouse bioassay. A biomolecular assay such as the sodium channel 3H-saxitoxin binding assay can satisfy both of these requirements but may be compromised by cross-reactivity with the

Andrew Negri; Lyndon Llewellyn

1998-01-01

322

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)

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.

Peck, Myron A.; Fell, Paul E.; Allen, Elizabeth A.; Gieg, Jennifer A.; Guthke, Carl R.; Newkirk, Michael D.

1994-03-01

323

Brominated flame retardants in fish and shellfish - levels and contribution of fish consumption to dietary exposure of Dutch citizens to HBCD.  

PubMed

In order to determine the contamination with brominated flame retardants (BFR) in fish regularly consumed by Dutch citizens, 44 samples of freshwater fish, marine fish, and shellfish were analyzed for polybrominated diphenyl ethers (PBDE), tetrabromobisphenol-A (TBBP-A) and its methylated derivative (me-TBBP-A), and hexabromocyclododecane (HBCD), including its alpha-, beta- and gamma-diastereomers. The highest BFR concentrations were found in pike-perch and eel from the highly industrialized and urbanized rivers Rhine and Meuse. The sum concentrations of BDE 28, 47, 99, 100, 153, 154, 183, 209, and brominated biphenyl (BB) 153 and HBCD (selection based on The European Food Safety Authority monitoring recommendation) ranged from below quantification limits to 17 ng/g wet weight (ww) in marine fish and in freshwater fish from 0.6 ng/g ww in pike-perch to 380 ng/g ww in eel. The BDE congener profile in all fish and shellfish samples is dominated by BDE 47, followed by BDE 99, except for eel in which BDE 100 is higher than BDE 99. BDE 209 was detected in two mussel samples, most likely due to BDE 209 contaminated particulate matter in their intestines. Total-HBCD (as determined by GC/electron capture negative ion (ECNI)-MS) was detected in 22 out of the 44 samples in concentrations between 0.20 ng/g in marine fish and 230 ng/g ww in eel. Three HBCD diastereomers were determined by HPLC/ESI-MS/MS. alpha-HBCD was the prevalent congener in most fish samples, followed by gamma-HBCD. beta-HBCD, TBBP-A and me-TBBP-A were only detected in a few samples and at low concentrations. A considerable difference was found between HBCD results obtained from GC/ECNI-MS and HPLC/ESI-MS/MS: the GC/ECNI-MS results were 4.4 times higher, according to regression analysis. There is hardly any data on human dietary exposure to HBCD available. We have estimated the fish-related dietary exposure of HBCD for the average Dutch population. The medium bound intake was estimated at 8.3 ng/day for a 70-kg person (0.12 ng/kg bodyweight/day). For this estimation, we relied mostly on HPLC/ESI-MS/MS data as we argue that these results are more accurate than those obtained by GC/ECNI-MS. PMID:18246585

van Leeuwen, Stefan P J; de Boer, Jacob

2008-02-01

324

Supramolecular solvents in solid sample microextractions: application to the determination of residues of oxolinic acid and flumequine in fish and shellfish.  

PubMed

Supramolecular solvents are here proposed firstly as extractants in solid sample microextractions. The approach was evaluated by extracting flumequine (FLU) and oxolinic acid (OXO), two widely used veterinary medicines, from fish and shellfish muscle using a supramolecular solvent made up of decanoic acid (DeA) reverse micelles. The antibiotics were extracted in a single step (approximately 15 min), at room temperature, using 400 microL of solvent. After centrifugation, an aliquot of the extract was directly analyzed by liquid chromatography and fluorescence, without the need of clean-up or solvent evaporation. Contrary to the previously reported methods, both OXO and FLU were quantitatively extracted from fish and shellfish, independently of sample composition. The high extraction efficiencies observed for these antibiotics were a consequence of their amphiphilic character which resulted in the formation of DeA-OXO and DeA-FLU mixed aggregates. The quality parameters of this quantitative method including sensitivity, linearity, selectivity, repeatability, trueness, ruggedness, stability, decision limit and detection capability were evaluated according to the 2002/657/EC Commission Decision. Quantitation limits in the different samples analyzed (salmon, sea trout, sea bass, gilt-head bream, megrim and prawns) ranged between 6.5 and 22 microg kg(-1) for OXO and, 5 and 15 microg kg(-1) for FLU. These limits were far below the current maximum residue limits (MRLs) set by the European Union (EU) (i.e. 100 and 600 microg kg(-1), for OXO and FLU, respectively). The trueness of the method was determined by analyzing a Certified Reference Material (CMR, BCR-725) consisting of a lyophilised salmon tissue material. Recoveries for fortified samples (50-100 microg kg(-1) of OXO and 50-600 microg kg(-1) of FLU) and their relative standard deviations were in the intervals 99-102% and 0.2-5%, respectively. The repeatability, expressed as relative standard deviation, was 3.6% for OXO and 2.3% for FLU ([OXO]=[FLU]=200 microg kg(-1) and n=11). PMID:20060977

Costi, Esther María; Sicilia, María Dolores; Rubio, Soledad

2010-02-26

325

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

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) has suggested that to not exceed the acute reference dose the levels should be below 45 µg kg-1 OA equivalents and 30 µg kg-1 AZA1 equivalents. A single-day validation was successfully conducted at these levels. If the regulatory levels are lowered towards the EFSA suggested values, the official methods prescribed in legislation (mouse and rat bioassay) will no longer be sensitive enough. The validated LC-MS/MS method presented has the potential to replace these animal tests. Electronic supplementary material The online version of this article (doi:10.1007/s00216-010-3886-2) contains supplementary material, which is available to authorized users. PMID:20552174

van Olst, Erik H. W.; Mulder, Patrick P. J.; de Boer, Jacob

2010-01-01

326

Development of the analysis of fecal stanols in the oyster Crassostrea gigas and identification of fecal contamination in shellfish harvesting areas.  

PubMed

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

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

2014-06-01

327

First evidence of "paralytic shellfish toxins" and cylindrospermopsin in a Mexican freshwater system, Lago Catemaco, and apparent bioaccumulation of the toxins in "tegogolo" snails (Pomacea patula catemacensis).  

PubMed

Exposure to cyanobacterial toxins in freshwater systems, including both direct (e.g., drinking water) and indirect (e.g., bioaccumulation in food webs) routes, is emerging as a potentially significant threat to human health. We investigated cyanobacterial toxins, specifically cylindrospermopsin (CYN), the microcystins (MCYST) and the "paralytic shellfish toxins" (PST), in Lago Catemaco (Veracruz, Mexico). Lago Catemaco is a tropical lake dominated by Cylindrospermopsis, specifically identified as Cylindrospermopsis catemaco and Cylindrospermopsis philippinensis, and characterized by an abundant, endemic species of snail (Pomacea patula catemacensis), known as "tegogolos," that is both consumed locally and commercially important. Samples of water, including dissolved and particulate fractions, as well as extracts of tegogolos, were screened using highly specific and sensitive ELISA. ELISA identified CYN and PST at low concentrations in only one sample of seston; however, both toxins were detected at appreciable quantities in tegogolos. Calculated bioaccumulation factors (BAF) support bioaccumulation of both toxins in tegogolos. The presence of CYN in the phytoplankton was further confirmed by HPLC-UV and LC-MS, following concentration and extraction of algal cells, but the toxin could not be confirmed by these methods in tegogolos. These data represent the first published evidence for CYN and the PST in Lago Catemaco and, indeed, for any freshwater system in Mexico. Identification of the apparent bioaccumulation of these toxins in tegogolos may suggest the need to further our understanding of the transfer of cyanobacterial toxins in freshwater food webs as it relates to human health. PMID:19651152

Berry, John P; Lind, Owen

2010-05-01

328

Shellfish tissues evaluated for Perkinsus spp. using the Ray's fluid thioglycollate medium culture assay can be used for downstream molecular assays.  

PubMed

Ray's fluid thioglycollate medium (RFTM) culture assay is the standard, recommended method for surveillance of Perkinsus spp. infections in marine molluscs. In this assay, shellfish tissues are incubated in RFTM, stained with Lugol's iodine solution to render Perkinsus spp. cells blue-black, and evaluated microscopically to rate infection intensities. A limitation of this assay, however, is the lack of pathogen species specificity. Generally, identification of Perkinsus spp. requires DNA sequence analysis of parallel or additional samples since the exposure to iodine is believed to hamper DNA amplification from samples processed by the RFTM assay. However, we show that P. marinus DNA can be successfully amplified by PCR from Crassostrea virginica tissues cultured in RFTM and stained with Lugol's iodine. The beneficial consequence is that, where necessary, DNA sequence data may be obtained from RFTM-cultured tissues, allowing the identification of the Perkinsus sp. responsible for an observed infection. This would obviate further sampling, representing gain of time and reduction in cost, where a Perkinsus sp. is unexpectedly observed in new host(s) or location(s) but where parallel samples are not available for molecular diagnostics. Laboratories without molecular diagnostic tools for Perkinsus spp. may fix presumptive Perkinsus sp.-positive culture material in 95% ethanol for transport to, and subsequent analysis by, a laboratory that does have this capacity. PMID:18814549

Audemard, C; Carnegie, R B; Burreson, E M

2008-08-01

329

[Analysis of the source, potential biological toxicity of heavy metals in the surface sediments from shellfish culture mudflats of Rudong Country, Jiangsu Province].  

PubMed

Concentrations of six heavy metals were measured in the surface sediments from shellfish culture mudflats of Rudong Country, Jiangsu Province in 2010. The geo-accumulation index (Igeo) was employed to evaluate the pollution level of heavy metals and the results showed that the heavy metal contamination could be divided into three groups: no contamination (Igeo), as in the case of Cu, Cd, Hg; light to moderate contamination (0 < Igeo, < 1), as in the case of Pb, As; and moderate contamination (1 < Igeo, < 2), as in the case of Zn. The pollution level of heavy metals followed the order of Zn > As > Pb > Cd > Cu > Hg. The potential biological toxicity was analyzed using sediment quality guidelines (SQG), as the guideline values, Cd showed no potential biological toxicity, As showed occasional potential biological toxicity in all sampling stations, Cu, Pb, Zn, Hg showed potential biological toxicity in some sampling stations, whereas Zn was the only one showing frequent potential biological toxicity in some sampling stations. Sigma TUs revealed that only one of the sampling stations showed significant acute toxicity, whereas the others showed no acute toxicity. Analysis of heavy metal contamination source through principal component analysis (PCA) revealed that the contribution rates of the top two principal components were 37.56% and 33.71%, respectively, indicating that the two main sources of heavy metals were industrial waste water and pollution from transportation and shipping. PMID:23213880

Li, Lei; Wang, Yun-long; Jiang, Mei; Yuan, Qi; Shen, Xin-qiang

2012-08-01

330

[Residual level and ecological risk assessment of OCPs and PCBs in sediments of mudflat shellfish culturing areas in Ningbo, Zhejiang Province of East China].  

PubMed

GC-ECD methods were adopted to determine the residual level of OCPs (including HCHs and DDTs) and PCBs in the surface sediments collected from mudflat shellfish culturing areas in Ningbo, with the sources of the OCPs and PCBs analyzed and the ecological risks of the residual OCPs and PCBs evaluated. The residual level of OCPs was 0.80-32.40 ng X g(-1), and that of PCBs was 3.20-33.33 ng X g(-1). The HCHs mainly came from long distance atmospheric transportation and historical residues, while the DDTs had new input at some sites, possibly coming from the application of dicofol. At most sites, there existed potential ecological risks of p, p'-DDT and DDTs, with strong indications in Qiangtou and Xidian where the residual level of p, p'-DDT was higher than the effect rang median (ERM), suggesting an ecological menace to the benthos. The residual PCBs at most sites were in low level ecological risk. PMID:22937662

Zhu, Yun-Hai; You, Zhong-Jie; Shentu, Ji-Kang; Zhong, Hui-Ying; Chai, Li-Yue

2012-06-01

331

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

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

García-Altares, María; Casanova, Alexis; Bane, Vaishali; Diogène, Jorge; Furey, Ambrose; de la Iglesia, Pablo

2014-01-01

332

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)

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.

Turrero, Pablo; Muñoz-Colmenero, A. Marta; Prado, Andrea; Garcia-Vazquez, Eva

2014-11-01

333

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

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

Stentiford, G D; Massoud, M S; Al-Mudhhi, S; Al-Sarawi, M A; Al-Enezi, M; Lyons, B P

2014-07-01

334

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)

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.

Vale, Paulo

2012-02-01

335

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

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

García-Altares, María; Casanova, Alexis; Bane, Vaishali; Diogène, Jorge; Furey, Ambrose; de la Iglesia, Pablo

2014-06-01

336

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

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

Rolland, Jean-Luc; Medhioub, Walid; Vergnes, Agnes; Abi-khalil, Celina; Savar, Véronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed

2014-01-01

337

Influence of Environmental Factors on the Paralytic Shellfish Toxin Content and Profile of Alexandrium catenella (Dinophyceae) Isolated from the Mediterranean Sea  

PubMed Central

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 ?mol 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

Laabir, Mohamed; Collos, Yves; Masseret, Estelle; Grzebyk, Daniel; Abadie, Eric; Savart, Véronique; Sibat, Manoella; Amzil, Zouher

2013-01-01

338

Development, Evaluation, and Standardization of a Real-Time TaqMan Reverse Transcription-PCR Assay for Quantification of Hepatitis A Virus in Clinical and Shellfish Samples  

PubMed Central

A standardized real-time reverse transcription-PCR (RT-PCR) assay has been developed for an accurate estimation of the number of genome copies of hepatitis A virus (HAV) in clinical and shellfish samples. Real-time procedures were based on the amplification of a fragment of the highly conserved 5? noncoding region and detection through an internal fluorescent probe, including TaqMan and beacon chemistries, in one- and two-step RT-PCR formats. The best performance in terms of sensitivity and reproducibility was achieved by a one-step TaqMan RT-PCR, with a sensitivity enabling the detection of 0.05 infectious unit and 10 copies of a single-stranded RNA (ssRNA) synthetic transcript. Standard reagents, such as a mengovirus strain and an ssRNA transcript, were employed as controls of nucleic acid extraction and RT-PCR, respectively. The test proved to be highly specific after a broad panel of enteric viruses was tested. Sequence alignment of target regions of the primers and probe proved them to be adequate for the quantification of all HAV genotypes. In addition, a quasispecies analysis of the mutant spectrum indicated that these regions are not prone to variability, thus confirming their robustness. PMID:16751488

Costafreda, M. Isabel; Bosch, Albert; Pintó, Rosa M.

2006-01-01

339

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...

340

Contrasting Physiological Responses of Two Populations of the Razor Clam Tagelus dombeii with Different Histories of Exposure to Paralytic Shellfish Poisoning (PSP)  

PubMed Central

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

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

341

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

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

Botelho, Maria João; Raimundo, Joana; Vale, Carlos; Ferreira, João Gomes

2014-06-01

342

Photocatalytic properties of nanocrystalline titanium dioxide films in the degradation of domoic acid in aqueous solution: potential for use in molluscan shellfish biotoxin depuration facilities.  

PubMed

Domoic acid (DA) is a water-soluble marine neurotoxin produced and released by certain species of the diatom genus Pseudo-nitzschia. Present in coastal waters, it can be a threat to public health and marine life, and can result in severe economic losses to the molluscan shellfish and crustacean harvesting industries. Here we report on the efficiency of nanocrystalline (NC) titania (TiO(2)) thin films used as a photocatalyst in the ultraviolet light photodegradation of DA. Titanium dioxide thin films produced by a sol-gel dip-coating method in the presence of polyethylene glycol of different molecular weights (200, 400 and 600) were deposited on glass substrates and crystallised at 90 degrees C. The films were characterised using spectroscopic ellipsometry, Fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy. The photocatalytic activity measurements were carried out by immersing the NC TiO(2) films in a DA solution (2500 ng ml(-1)) and then exposing them for various times at room temperature to UVA irradiation (lambda = approximately 350 nm). The degradation of DA, quantified by HPLC analysis, was not significant when using daylight or ultraviolet light irradiation alone, whereas the NC TiO(2) films prepared at low temperature proved to be a very efficient photocatalyst when used in conjunction with UVA light. The effectiveness of the photodegradation was improved by increasing molecular weight of polyethylene glycol, which increased the thickness of the film. The presence, transformation and degradation of three DA isomers were observed. The approach may eventually be practical for destroying DA in seawater used by aquaculture industry depuration facilities. PMID:19680896

Djaoued, Y; Robichaud, J; Thibodeau, M; Balaji, S; Tchoukanova, N; Bates, S S

2009-02-01

343

The interaction of human microbial pathogens, particulate material and nutrients in estuarine environments and their impacts on recreational and shellfish waters.  

PubMed

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 contamination event occurred. Further work, however, is still required to understand and predict the potential human infectivity of pathogenic organisms alongside the better design of early warning systems and surveillance measures for risk assessment purposes. PMID:25043898

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

344

Improved microwave-assisted wet digestion procedures for accurate Se determination in fish and shellfish by flow injection-hydride generation-atomic absorption spectrometry.  

PubMed

Accurate determination of Se in biological samples, especially fish and shellfish, by hydride generation techniques has generally proven troublesome owing to the presence of organoselenium that cannot readily converted into inorganic selenium under usual oxidising conditions. Further improvements in the oxidation procedures are needed so as to obtain accurate concentration values when this type of samples is analyzed. Microwave-assisted wet digestion (MAWD) procedures of seafood based on HNO3 or the mixture HNO3/H2O2 and further thermal reduction of the Se(VI) formed to Se(IV) were evaluated. These procedures were as follows: (I) without H2O2 and without heating to dryness; (II) without H2O2 and with heating to dryness; (III) with H2O2 and without heating to dryness; (IV) with H2O2 and with heating to dryness. In general, low recoveries of selenium are obtained for several marine species (e.g., crustaceans and cephalopods), which may be ascribed to the presence of Se forms mainly associated with nonpolar proteins and lipids. Post-digestion UV irradiation proved very efficient since not only complete organoselenium decomposition was achieved but also the final step required for prereduction of Se(VI) into Se(IV) (i.e. heating at 90 degrees C for 30 min in 6M HCl) could be avoided. With the MAWD/UV procedure, the use of strong oxidising agents (persuphate, etc.) or acids (e.g. perchloric acid) which are typically applied prior to Se determination by hydride generation techniques is overcome, and as a result, sample pre-treatment is significantly simplified. The method was successfully validated against CRM DOLT-2 (dogfish liver), CRM DORM-2 (dogfish muscle) and CRM TORT-2 (lobster hepatopancreas). Automated ultrasonic slurry sampling with electrothermal atomic absorption spectrometry was also applied for comparison. Total Se contents in ten seafood samples were established. Se levels ranged from 0.7 to 2.9 microg g(-1). PMID:17481413

Lavilla, I; González-Costas, J M; Bendicho, C

2007-05-22

345

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)

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 ?g 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 whole scallops on Georges Bank are unlikely to change based on these results, it seems plausible that a management strategy requiring at-sea testing of scallop gonads for PSP may be necessary in order for a safe roe-on scallop fishery from this region to be feasible.

DeGrasse, Stacey; Vanegas, Camilo; Conrad, Stephen

2014-05-01

346

Improving early detection of exotic or emergent oyster diseases in France: identifying factors associated with shellfish farmer reporting behaviour of oyster mortality.  

PubMed

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 reporting, rather than early detection of a disease outbreak. Both economic compensation and the farmers' non-economic values and perceptions should be considered to improve oyster farmers' reporting compliance and sustainability of the reporting system. Education and participatory approaches could help to change these attitudes and thus improve oyster farmers' compliance with reporting duties, resulting in improved early detection of epidemics and emerging or exotic oyster diseases. PMID:24880624

Lupo, C; Osta Amigo, A; Mandard, Y V; Peroz, C; Renault, T

2014-09-01

347

QPX Parasite Shellfish - New Jersey  

NSDL National Science Digital Library

This State of New Jersey fact sheet (PDF) briefly outlines the ecological and socioeconomic risks associated with Quahog Parasite X (QPX), a parasite that kills hard clams. QPX was first discovered in New Jersey in the 1970s.

State of New Jersey

348

FISH AND SHELLFISH what's inside  

E-print Network

the Fire, 3 Grilled Spiny Lobster Tails, 4 Whitefish in Foil, 4 Charcoal Grilled Red Snapper Steaks, 4 Savory Grilled Soft-Shell Crabs, 8 Sesame Rainbow Trout, 8 Boiled Lobster, 10 Charcoal Broiled Scallops and the fire is ready. Make the charcoal layer slightly wider than the food to be cooked on the grill. Wood

349

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

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

Silva, C; Yáñez, E; Martín-Díaz, M L; DelValls, T A

2012-04-01

350

Using stable isotopes to monitor anthropogenic nitrogen inputs to estuaries.  

PubMed

Use of stable nitrogen isotope ratios is one method that has been proposed to indicate anthropogenic nutrient enrichment in estuarine systems. However, the role of stable isotopes as a tool in long-term ecosystem monitoring has not been fully developed. Resident producer and consumer species were collected from marshes dominated by Spartina alterniflora and subject to a range of anthropogenic impacts in Cape Cod, Massachusetts, and in Great South Bay and Jamaica Bay, New York. Tissue isotope ratios of Spartina alterniflora, Ulva lactuca, Fundulus heteroclitus, and Geukensia demissa were analyzed in order to determine which organisms are the most sensitive indicators of changes in anthropogenic nitrogen source and loading. Power analysis was used to determine the sample sizes necessary to detect change in nutrient source using the species sampled. Relationships between the delta15N values of the species sampled and watershed population density and residential development were evaluated. Population density was a better indicator of anthropogenic nitrogen impact than residential development, since most anthropogenic nitrogen in the study marshes was derived from wastewater. Consumer species demonstrated lower within-site variability than producer species and would therefore require smaller sample sizes to detect changes in nitrogen source and loading. PMID:18372553

Bannon, Rebecca O; Roman, Charles T

2008-01-01

351

Interspecific comparison of the mechanical properties of mussel byssus.  

PubMed

Byssally tethered mussels are found in a variety of habitats, including rocky intertidal, salt marsh, subtidal, and hydrothermal vents. One key to the survival of mussels in these communities is a secure attachment, achieved by the production of byssal threads. Although many studies have detailed the unique biomechanical properties of byssal threads, only a few prevalent species have been examined. This study assesses the variation in the mechanical properties of byssus in a broad range of mussel species from diverse environments, including intertidal and subtidal Mytilus edulis, Modiolus modiolus, Geukensia demissa, Bathymodiolus thermophilus, and Dreissena polymorpha. A tensometer was used to measure quasi-static and dynamic mechanical properties of individual threads, and several aspects of morphology were quantified. The results indicate that thread mechanical properties vary among mussel species, and several novel properties were observed. For example, of the species examined, D. polymorpha threads were the strongest, stiffest, least resilient, and fastest to recover after partial deformation. Threads of M. modiolus were characterized by the presence of two distinct yield regions prior to tensile failure. This comparative study not only provides insight into the ecological limitations and evolution of mussels, but also suggests new models for the design of novel biomimetic polymers. PMID:17179385

Brazee, Shanna L; Carrington, Emily

2006-12-01

352

Hemigrapsus sanguineus in Long Island salt marshes: experimental evaluation of the interactions between an invasive crab and resident ecosystem engineers  

PubMed Central

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

Fournier, Alexa M.; Furman, Bradley T.; Carroll, John M.

2014-01-01

353

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

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).

Thiede, M.E.; Duncan, J.P.

1994-03-01

354

21 CFR 1240.60 - Molluscan shellfish.  

Code of Federal Regulations, 2011 CFR

...1240.60 Section 1240.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION CONTROL...not offer for transportation, or transport, in interstate traffic...

2011-04-01

355

FISH AND SHELLFISH PREFERENCES OF HOUSEHOLD  

E-print Network

. Garfield·· Contents May 1952 Survey methods and characterist i cs · · · 0 0 0 · · · · . . .Major findings informat on as to survey me hods . characteristic s . etc. than is shown belo · SURVEY METHODS

356

21 CFR 1240.60 - Molluscan shellfish.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION CONTROL OF COMMUNICABLE DISEASES Specific Administrative Decisions Regarding Interstate Shipments § 1240.60 Molluscan...

2010-04-01

357

So you are thinkingSo you are thinking about growing shellfish?about growing shellfish?about growing shellfish?about growing shellfish?  

E-print Network

oysterOlympia oyster Ostrea luridaOstrea lurida yy Crassostrea virginicaCrassostrea virginica #12;ClamsClams Manila clamManila clam Tapes philippinarumTapes philippinarum Hard clam northern quahogHard clam northern quahogPacific littleneck clamPacific littleneck clam Protothaca stamineaProtothaca staminea Hard clam

Florida, University of

358

Restricting Prey Dispersal Can Overestimate the Importance of Predation in Trophic Cascades  

PubMed Central

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

Geraldi, Nathan R.; Macreadie, Peter I.

2013-01-01

359

Activity measurements of a suite of radionuclides (241Am, 239,240Pu, 238Pu, 238U, 234U, 235U, 232Th, 230Th, 228Th, 228Ra, 137Cs, 210Pb, 90Sr and 40K) in biota reference material (Ocean Shellfish): CCRI(II)-S3  

NASA Astrophysics Data System (ADS)

In 2005, the CCRI decided that a comparison undertaken from 2002 to 2008 by the NIST (under the auspices of the Inter-America Metrology System [SIM]) in the development of a new biota (Ocean Shellfish) standard reference material (SRM) was sufficiently well constructed that it could be converted into a supplementary comparison under CCRI(II), with comparison identifier CCRI(II)-S3. This would enable the comparison to be used to support calibration and measurement capability (CMC) claims for radionuclide measurements in reference materials (specifically, animal-based organic materials). Previous comparisons of radionuclides have been of single or multiple nuclides in non-complex matrices and results of such could not be extended to support capabilities to measure the same nuclides in reference materials. The results of this comparison have been used to determine the certified reference value of the SRM. The key comparison working group (KCWG) of the CCRI(II) has approved this approach as a mechanism to link all the results to certified 'reference values' in lieu of the key comparison reference value (KCRV) of these specified radionuclides in this type of matrix (shellfish) so as to support CMCs of similar materials submitted by the present participants. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Nour, S.; Karam, L. R.; Inn, K. G. W.

2012-01-01

360

Macroinvertebrate and fish populations in a restored impounded salt marsh 21 years after the reestablishment of tidal flooding.  

PubMed

During the last two decades, the State of Connecticut has restored tidal flow to many impounded salt marshes. One of the first of these and the one most extensively studied is Impoundment One in the Barn Island Wildlife Management Area in Stonington, Connecticut. In 1990, twelve years after the re-establishment of tidal flooding, the density of the marsh snail Melampus bidentatus, the numerically dominant macroinvertebrate of the high marsh, in Impoundment One was about half that in reference marshes below the breached impoundment dike. By 1999 the densities of Melampus above and below the dike were not significantly different, but the shell-free biomass was greater above the dike as a result of the somewhat larger number and size of the snails there. Twenty-one years after the renewal of tidal flooding, three marsh macroinvertebrates (the amphipods Orchestia grillus and Uhlorchestia spartinophila and the mussel Geukensia demissa) were significantly less abundant in the previously impounded marsh than in the reference marshes, whereas another amphipod (Gammarus palustris) was more abundant above the breached dike where conditions appeared to be somewhat wetter. In 1991 the fish assemblage in a mosquito-control ditch in Impoundment One was similar to that in a ditch below the breached dike; however, the common mummichog Fundulus heteroclitus appeared to be less abundant in the restoring marsh. By 1999 the number of mummichogs caught in ditches was significantly greater in Impoundment One than in the reference marsh, but the numbers of mummichogs trapped along the tidal creek were comparable above and below the dike. The results obtained in this study and those of other restoring marshes at Barn Island indicate the full recovery of certain animal populations following the reintroduction of tidal flow to impounded marshes may require up to two or more decades. Furthermore, not only do different species recover at different rates on a single marsh, but the time required for the recovery of a particular species may vary widely from marsh to marsh, often independently of other species. PMID:12071502

Swamy, Varun; Fell, Paul E; Body, Misha; Keaney, Michael B; Nyaku, Mawuli K; McIlvain, Elizabeth C; Keen, Alice L

2002-04-01

361

Per Capita Annual Utilization and Consumption of Fish and Shellfish  

E-print Network

this speculation. This paper is an attempt to quantify the actual consumption in Hawaii for the period 1970 in "Fisheries of the United States" (Bell, 1978) where national per capita estimates are Linda L. Hudgins foreign countries, and 3) interstate shipments from the mainland United States. Table I gives totals

362

Water quality and shellfish sanitation. [Patuxent and Choptank River watersheds  

NASA Technical Reports Server (NTRS)

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.

Eisenberg, M.

1978-01-01

363

East Coast Shellfish Hatchery and Nursery List 2012 Gef Flimlin  

E-print Network

.nedsislandoysters.com US Department of Commerce - OY, HC, BS, SU National Marine Fisheries Service Milford Laboratory 212 for inclusion in the next publication. If someone is using this list and cannot reach a business because, by no means, be construed as an advertisement for any of these companies by either the author or Rutgers

Florida, University of

364

New England Shellfish Beds Reopen After Toxic Red Algae Recedes  

NSDL National Science Digital Library

This PBS article describes red tide, a phenomenon caused by phytoplankton in coastal waters. The site includes brief summaries of the causes and impacts of red tide, both on health and the tourism industry. A link to a PDF version of the article is provided.

Annie Schleicher

365

REVIEW Open Access Toxic marine microalgae and shellfish poisoning  

E-print Network

discussed topic in recent years, with research focusing on the possible future impacts of changing the key toxic syndromes and gather together the disparate reported data on their epidemiology from UK records and monitoring procedures. Secondly, using NHS hospital admissions and GP records from Wales, we

Hays, Graeme

366

NOAA Support for Puget Sound Shellfish: Native Oysters, Abalone &  

E-print Network

intertidal zone, providing three dimensional, complex habitat attractive to fish-- December 2011 Partners · Squaxin Island, Suquamish, Skokomish, Port Gamble S'Klallam, Swinomish, Samish, Jamestown S'Klallam, Lummi

367

Impact of elevated CO2 on shellfish calcification  

Microsoft Academic Search

Ocean acidification resulting from human emissions of carbon dioxide has already lowered and will further lower surface ocean pH. The consequent decrease in calcium carbonate saturation potentially threatens calcareous marine organisms. Here, we demonstrate that the calcification rates of the edible mussel (Mytilus edulis) and Pacific oyster (Crassostrea gigas) decline linearly with increasing pCO2. Mussel and oyster calcification may decrease

Frédéric Gazeau; Christophe Quiblier; Jeroen M. Jansen; Jean-Pierre Gattuso; Jack J. Middelburg; Carlo H. R. Heip

2007-01-01

368

50 CFR 14.21 - Shellfish and fishery products.  

Code of Federal Regulations, 2011 CFR

...Customs port. (2) Except for wildlife requiring a permit pursuant to part 17 or part 23 of this subchapter, live aquatic invertebrates of the Class Pelecypoda (commonly known as oysters, clams, mussels, and scallops) and the eggs, larvae, or...

2011-10-01

369

50 CFR 14.21 - Shellfish and fishery products.  

Code of Federal Regulations, 2010 CFR

...Customs port. (2) Except for wildlife requiring a permit pursuant to part 17 or part 23 of this subchapter, live aquatic invertebrates of the Class Pelecypoda (commonly known as oysters, clams, mussels, and scallops) and the eggs, larvae, or...

2010-10-01

370

50 CFR 14.21 - Shellfish and fishery products.  

Code of Federal Regulations, 2012 CFR

...Customs port. (2) Except for wildlife requiring a permit pursuant to part 17 or part 23 of this subchapter, live aquatic invertebrates of the Class Pelecypoda (commonly known as oysters, clams, mussels, and scallops) and the eggs, larvae, or...

2012-10-01

371

50 CFR 14.21 - Shellfish and fishery products.  

Code of Federal Regulations, 2013 CFR

...Customs port. (2) Except for wildlife requiring a permit pursuant to part 17 or part 23 of this subchapter, live aquatic invertebrates of the Class Pelecypoda (commonly known as oysters, clams, mussels, and scallops) and the eggs, larvae, or...

2013-10-01

372

50 CFR 14.21 - Shellfish and fishery products.  

Code of Federal Regulations, 2014 CFR

...Customs port. (2) Except for wildlife requiring a permit pursuant to part 17 or part 23 of this subchapter, live aquatic invertebrates of the Class Pelecypoda (commonly known as oysters, clams, mussels, and scallops) and the eggs, larvae, or...

2014-10-01

373

RESEARCH Open Access Maternal fish and shellfish consumption and  

E-print Network

associations with health effects observable at later ages, such as allergic asthma. Keywords: Fish intake for the effects observed, determine the persistence of the associations seen at age 2, and investigate potential

Paris-Sud XI, Université de

374

Hydrocarbon pollution of edible shellfish by an oil spill  

Microsoft Academic Search

A spill of 650,000 to 700,000 l of No. 2 fuel oil has contaminated the coastal areas of Buzzards Bay, Massachusetts (USA). Gas chromatography demonstrates the presence of this oil in the sediments of the affected area. Two months after the accident, essentially unchanged oil is still being released from the sediments. The presence of the same pollutant is demonstrated

M. Blumer; G. Souza; J. Sass

1970-01-01

375

Archaeological shellfish size and later human evolution in Africa  

PubMed Central

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

Klein, Richard G.; Steele, Teresa E.

2013-01-01

376

Tracking responses to the 2010 Deepwater Horizon oil spill using trace elements in molluscan shells and tissues  

NASA Astrophysics Data System (ADS)

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, we can monitor the sub-monthly incorporation of hydrocarbon components into shells, such as trace metals (e.g., V, Ni, Cu and Cr), while simultaneously measuring changes in shell growth rate. We will also measure concentrations of metals in soft tissues from specimens collected since May 2010. Trace metal concentrations will be determined using ICPMS. Annual and sub-annual growth rates will be calculated from ?13C and ?18O profiles derived from ontogentic sampling of the molluscs' shells. The comparisons between historic, baseline and post-landfall specimens will allow us to assess the changing conditions of these species and their food webs as drilling expanded in the Gulf during the 20th century, and therefore distinguish the immediate impact of the Deepwater Horizon spill from these background factors. In this way, we will also trace secondary impacts (not related to fouling by direct contact) of hydrocarbons through trophic levels of the coastal ecosystem.

Roopnarine, P. D.; Anderson, L.; Roopnarine, D.; Gillikin, D. P.; Goodwin, D.

2010-12-01

377

Phylogeny, evolution, and systematics of the Galea musteloides complex (Rodentia: Caviidae)  

E-print Network

) from the central Bolivian Andes, G. m. auceps (Thomas, 1911) from the Altiplano region around Lake Titicaca, and G. m. demissa (Thomas, 1921) from the Bolivian lowlands adjacent to the Andean foothills

378

Hard clam aquaculture is the largest and most valuable of the shellfish  

E-print Network

mollusks that live in saline (>25 parts per thou- sand) waters and cannot tolerate low salinities above the hinge. With the extra weight of the shell, larvae no longer swim freely and settle of mud and sand as substrate but other suitable substrates are pure sand, gravel and mud. Larval setting

Florida, University of

379

Harvesting Shellfish: Unit F#2 Grade 4. Project COULD: Career Orientation Utilizing Language Development.  

ERIC Educational Resources Information Center

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…

Coos County Intermediate Education District, North Bend, OR.

380

Microbial flora and distribution of Vibrio parahaemolyticus in molluscan shellfish, water, and sediment  

E-print Network

of the requirement for the degree of MASTER OF SCIENCE December 1972 Major Subject: Microbiology (Food Microbiology) MICROBIAL FLORA AND DISTRIBUTION OF VIBRIO nanavacasnvv~r~ric IN Mnr tDcraN cHvv v FvcH f MhllW ilVU I l4U WATER, AND SEDIMENT A Thesis... proposed by Wagatsuma (47) for the "Kanagawa phenomenon". Incubation was at 37 C for 24 hr. ~S1 Serological identification was made by means of slide agglutination with K antisera (Nichimen Co. , New York). K pool and monovalent reactions were...

Thompson, Charles Albert

1972-01-01

381

Pierisins and CARP-1: ADP-ribosylation of DNA by ARTCs in butterflies and shellfish.  

PubMed

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

Nakano, Tsuyoshi; Takahashi-Nakaguchi, Azusa; Yamamoto, Masafumi; Watanabe, Masahiko

2015-01-01

382

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Office of Acquisition and Logistics, Department of Veterans Affairs...Office of Acquisition and Logistics (OA&L), Department of...Office of Acquisition and Logistics (049A5A), Department of...McLamb, Program Analyst, Enterprise Records Service. [FR...

2010-03-18

383

Cell Structure of Shellfish Pathogens and Hyperparasites in the Genera Minchinia, Urosporidium, Haplosporidium,  

E-print Network

"pepper crab disease" by work- ers in the seafood industry. The en- cysted metacercariae become black (possibly Paranisakiopsis pectinis Cobb, 1930; see Lichtenfels et aI., 1977) becomes black when also becomes black when spores of the balanosp

384

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...

385

POLLUTION-ASSOCIATED DISEASES AND ABNORMALITIES OF FISH AND SHELLFISH: A REVIEW  

E-print Network

BULLETIN: VOL. 76, NO.4, 1979. and environmental stress that eventually causes mortality. The distinction between "infection" and "dis- ease" must be kept in mind. Most organisms are constantly hosts and mortalities comparable to the great plagues of the Middle Ages may sweep through animal populations. In marine

386

Genetic Diversity of Rotavirus Strains Circulating in Environmental Water and Bivalve Shellfish in Thailand  

PubMed Central

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

Kittigul, Leera; Panjangampatthana, Apinya; Rupprom, Kitwadee; Pombubpa, Kannika

2014-01-01

387

Taxonomic Difficulties in Red Tide and Paralytic Shellfish Poison Studies: The “Tamarensis Complex” of Gonyaulax  

Microsoft Academic Search

The type illustrations of the dinoflagellate Gonyaulax tamarensis contain an apparent reversal of the epithecal plates. Furthermore a culture from the type locality has been found not to be toxigenic. These two features have led a recent author to doubt the appropriateness of the allocation of toxic populations in the North Atlantic to this species or a variety of it

F. J. R. Taylor

1975-01-01

388

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 ...

389

Aquatic Toxicology 80 (2006) 8291 The uptake, distribution and elimination of paralytic shellfish  

E-print Network

as derivatives of saxitoxin (STX), which is the most potent PST. PSTs can be classified into three major groups. On a molar basis, non-sulfated carbamate toxins, saxitoxin, and its N-1-hydroxy derivative neosaxitoxin (neo

Yu, K.N.

2006-01-01

390

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...

391

50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2014 CFR

...following species: Arctic char (Salvelinus alpinis ), lake trout (Salvelinus namaycush ), brook trout (Salvelinus fontinalis ), and Dolly Varden (Salvelinus malma ). Closed season means the time when fish, wildlife, or...

2014-10-01

392

36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2011 CFR

...following species: Arctic char (Salvelinus alpinis ), lake trout (Salvelinus namaycush ), brook trout (Salvelinus fontinalis ), and Dolly Varden (Salvelinus malma ). Closed season means the time when fish, wildlife, or...

2011-07-01

393

50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2013 CFR

...following species: Arctic char (Salvelinus alpinis), lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and Dolly Varden (Salvelinus malma). Closed season means the time when fish, wildlife, or...

2013-10-01

394

36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2012 CFR

...following species: Arctic char (Salvelinus alpinis), lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and Dolly Varden (Salvelinus malma). Closed season means the time when fish, wildlife, or...

2012-07-01

395

36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2013 CFR

...following species: Arctic char (Salvelinus alpinis), lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and Dolly Varden (Salvelinus malma). Closed season means the time when fish, wildlife, or...

2013-07-01

396

50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2010 CFR

...following species: Arctic char (Salvelinus alpinis ), lake trout (Salvelinus namaycush ), brook trout (Salvelinus fontinalis ), and Dolly Varden (Salvelinus malma ). Closed season means the time when fish, wildlife, or...

2010-10-01

397

50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2011 CFR

...following species: Arctic char (Salvelinus alpinis ), lake trout (Salvelinus namaycush ), brook trout (Salvelinus fontinalis ), and Dolly Varden (Salvelinus malma ). Closed season means the time when fish, wildlife, or...

2011-10-01

398

36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2014 CFR

...following species: Arctic char (Salvelinus alpinis), lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and Dolly Varden (Salvelinus malma). Closed season means the time when fish, wildlife, or...

2014-07-01

399

36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2010 CFR

...following species: Arctic char (Salvelinus alpinis ), lake trout (Salvelinus namaycush ), brook trout (Salvelinus fontinalis ), and Dolly Varden (Salvelinus malma ). Closed season means the time when fish, wildlife, or...

2010-07-01

400

50 CFR 100.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.  

Code of Federal Regulations, 2012 CFR

...following species: Arctic char (Salvelinus alpinis), lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and Dolly Varden (Salvelinus malma). Closed season means the time when fish, wildlife, or...

2012-10-01

401

What You Need to Know about Mercury in Fish and Shellfish  

MedlinePLUS

... recreationally by family or friends? Before you go fishing, check your Fishing Regulations Booklet for information about recreationally caught fish. ... fish species commonly caught during recreational and subsistence fishing activity.

402

Changes in commercially fished shellfish stocks and shorebird populations in the Wash, England  

Microsoft Academic Search

The Wash, in eastern England, supports internationally important populations of 11 species of shorebird. A major commercial shellfishery provides potential conflict between fishermen and nature conservation interests. During the 1990s, high fishing mortality and low recruitment substantially reduced the stocks of cockle (Cerastoderma edule) and mussel (Mytilus edulis). Population models, constructed from estimates of survival and recruitment, indicated that declines

Philip W. Atkinson; Nigel A. Clark; Mike C. Bell; Peter J. Dare; Jacquie A. Clark; Philip L. Ireland

2003-01-01

403

The first evidence of paralytic shellfish toxins in the freshwater cyanobacterium Cylindrospermopsis raciborskii, isolated from Brazil  

Microsoft Academic Search

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 São 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

Néstor Lagos; Hideyuki Onodera; Pedro Antonio Zagatto; Dar??o Andrinolo; Sandra M. F. Q Azevedo; Yasukatsu Oshima

1999-01-01

404

Amnesic shellfish poisoning (ASP) toxins in plankton and molluscs from Luanda Bay, Angola  

Microsoft Academic Search

The presence of ASP toxins in Luanda Bay, an area 2700km apart from the closest record of this type of toxicity and with a different hydrographic regime, was studied. Two outbreaks were confirmed by LC\\/MS\\/MS with presence of domoic acid and some isomers both, in plankton and in three of the most important bivalve species from the area. Domoic acid

Juan Blanco; Filomena Livramento; Isabel Menezes Rangel

2010-01-01

405

New Genetic Test Can Detect Clam Disease Crippling Shellfish Industry and Threatening Aquaculture Operations  

NSDL National Science Digital Library

This Woods Hole Oceanographic Institute news release reports that a genetic test has been developed to detect QPX (Quahog Parasite Unknown), a crippling disease occurring in clam beds from Cape Cod south to Virginia and north to Canada. The article features Woods Hole scientists Rebecca Gast and Roxanna Smolowitz and links to the related Oceanus magazine article.

Shelley Dawicki

406

A multidisciplinary approach to evaluating impacts of shellfish aquaculture on benthic communities  

Microsoft Academic Search

The impact of suspended mussel culture (Mytilus edulis, M. trossulus) on the benthos of a small Nova Scotia cove (7 m depth) was assessed using meehods involving both benthic metabolism and\\u000a community structure. Due to deposition of mussel feces and pseudofeces, sedimentation rate was higher under the mussel culture\\u000a lines than at an adjacent reference site of similar sediment texture.

J. Grant; A. Hatcher; D. B. Scott; P. Pocklington; C. T. Schafer; G. V. Winters

1995-01-01

407

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...

408

Ocean Warming, More than Acidification, Reduces Shell Strength in a Commercial Shellfish Species during Food Limitation  

PubMed Central

Ocean surface pH levels are predicted to fall by 0.3–0.4 pH units by the end of the century and are likely to coincide with an increase in sea surface temperature of 2–4°C. The combined effect of ocean acidification and warming on the functional properties of bivalve shells is largely unknown and of growing concern as the shell provides protection from mechanical and environmental challenges. We examined the effects of near-future pH (ambient pH –0.4 pH units) and warming (ambient temperature +4°C) on the shells of the commercially important bivalve, Mytilus edulis when fed for a limited period (4–6 h day?1). After six months exposure, warming, but not acidification, significantly reduced shell strength determined as reductions in the maximum load endured by the shells. However, acidification resulted in a reduction in shell flex before failure. Reductions in shell strength with warming could not be explained by alterations in morphology, or shell composition but were accompanied by reductions in shell surface area, and by a fall in whole-body condition index. It appears that warming has an indirect effect on shell strength by re-allocating energy from shell formation to support temperature-related increases in maintenance costs, especially as food supply was limited and the mussels were probably relying on internal energy reserves. The maintenance of shell strength despite seawater acidification suggests that biomineralisation processes are unaffected by the associated changes in CaCO3 saturation levels. We conclude that under near-future climate change conditions, ocean warming will pose a greater risk to shell integrity in M. edulis than ocean acidification when food availability is limited. PMID:24489785

Mackenzie, Clara L.; Ormondroyd, Graham A.; Curling, Simon F.; Ball, Richard J.; Whiteley, Nia M.; Malham, Shelagh K.

2014-01-01

409

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...

410

Overfishing and the Replacement of Demersal Finfish by Shellfish: An Example from the English Channel  

PubMed Central

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

Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M.

2014-01-01

411

The influence of fly ash and shell-fish on physical property of concrete cement  

NASA Astrophysics Data System (ADS)

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.

Rauf, Nurlaela; Hasruddin, M.

2012-06-01

412

JOURNAL OF SHELLFISH RESEARCH IVOLUME 25, NUMBER 2 AUGUST ZOO6 1  

E-print Network

mm, and stocked in pearl nets (34 x 34 cni) at densities ranging from 200-500 oysters per net. The pearl nets. in vertical arrays of 4 nets, were deployed at the adult growout site during July for 3 seed required to stock a significantly expanded adult grow- out system in West Harbor. JOD AT OYSTER

Allam, Bassem

413

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...

414

Rocky Intertidal Zonation Pattern in Antofagasta, Chile: Invasive Species and Shellfish Gathering  

PubMed Central

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

Castilla, Juan Carlos; Manríquez, Patricio H.; Delgado, Alejandro; Ortiz, Verónica; Jara, María Elisa; Varas, Manuel

2014-01-01

415

Official Surveillance of Hepatitis A Virus: Description of an HAV Detection Method in Shellfish  

Microsoft Academic Search

Currently, hepatitis A virus (HAV) detection is not yet included in the regulation provided for food safety controls. However,\\u000a the 2073\\/2005\\/EC regulation on microbiological criteria applied to food takes into account the sanitary issue as to viral\\u000a contamination of food but postpones the definition of specific criteria for pathogenetic virus detection until reliable analytical\\u000a methods are available. In this study,

Laura Serracca; Francesca Gallo; Irene Rossini; Alessandro Benedetto; Daniela Lacerenza; Maria Rita Callipo; Milena Monnier; Maria Goria

2009-01-01

416

Animal-free paralytic shellfish toxin testing--the Canadian perspective to improved health protection.  

PubMed

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

Rourke, Wade A; Murphy, Cory J

2014-01-01

417

Contaminant levels in fish and shellfish from the EMAP-Estuaries Louisiana Province  

SciTech Connect

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.

Benson, W.H.; O`Neal, J.M.; Allgood, J.C. [Univ. of Mississippi, University, MS (United States); Summers, J.K. [Environmental Protection Agency, Gulf Breeze, FL (United States)

1994-12-31

418

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

Federal Register 2010, 2011, 2012, 2013, 2014

...reverse transcription quantitative polymerase chain reaction (RT-qPCR) for norovirus GII with 80% recovery). Areas of...Period, Using Semiquantitative Real-Time Reverse Transcription PCR,'' Journal of Food Protection, vol. 71, pp. 1427-...

2011-10-20

419

Solar pond seawater heating system for shellfish mariculture. Final progress report  

SciTech Connect

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.

Kassner, J.

1984-01-01

420

Assessment of blue mussel Mytilus edulis fisheries and waterbird shellfish-predator management in the Danish Wadden Sea.  

PubMed

We assessed the blue mussel Mytilus edulis fishery management scheme introduced in 1994 in the Danish Wadden Sea that regulate fishing vessels, fishery quota, set-aside for mussel-eating birds and established zones closed to mussel fishery. The results showed (i) a reduction in the blue mussel biomass and mussel bed areas in zones closed to fishery, (ii) decrease in eiders Somateria mollissima numbers and increase or stable numbers for oystercatcher Haematopus ostralegus and herring gull Larus argentatus and (iii) that energy estimations based on ecological food requirements for the mussel-eating birds should be at least three times larger, than the amount set-aside in the mussel management scheme. It is concluded that the mussel management scheme had been unable to stabilize or increase the blue mussel stocks and to secure stable or increasing numbers for all target bird species. Thus, it is recommended to revise the present blue mussel management scheme in the Danish Wadden Sea, to continue and improve mussel stock and bird surveys, and to consider novel studies of the mussel-eating birds' energetics for improved set-aside estimates and future assessments. PMID:21090002

Laursen, Karsten; Kristensen, Per Sand; Clausen, Preben

2010-11-01

421

Zebrafish neurotoxicity from aphantoxins--cyanobacterial paralytic shellfish poisons (PSPs) from Aphanizomenon flos-aquae DC-1.  

PubMed

Aphanizomenon flos-aquae (A. flos-aquae), a cyanobacterium frequently encountered in water blooms worldwide, is source of neurotoxins known as PSPs or aphantoxins that present a major threat to the environment and to human health. Although the molecular mechanism of PSP action is well known, many unresolved questions remain concerning its mechanisms of toxicity. Aphantoxins purified from a natural isolate of A. flos-aquae DC-1 were analyzed by high-performance liquid chromatography (HPLC), the major component toxins were the gonyautoxins1 and 5 (GTX1 and GTX5, 34.04% and 21.28%, respectively) and the neosaxitoxin (neoSTX, 12.77%). The LD50 of the aphantoxin preparation was determined to be 11.33 ?g/kg (7.75 ?g saxitoxin equivalents (STXeq) per kg) following intraperitoneal injection of zebrafish (Danio rerio). To address the neurotoxicology of the aphantoxin preparation, zebrafish were injected with low and high sublethal doses of A. flos-aquae DC-1 toxins 7.73 and 9.28 ?g /kg (5.3 and 6.4 ?g STXeq/kg, respectively) and brain tissues were analyzed by electron microscopy and RT-PCR at different timepoints postinjection. Low-dose aphantoxin exposure was associated with chromatin condensation, cell-membrane blebbing, and the appearance of apoptotic bodies. High-dose exposure was associated with cytoplasmic vacuolization, mitochondrial swelling, and expansion of the endoplasmic reticulum. At early timepoints (3 h) many cells exhibited characteristic features of both apoptosis and necrosis. At later timepoints apoptosis appeared to predominate in the low-dose group, whereas necrosis predominated in the high-dose group. RT-PCR revealed that mRNA levels of the apoptosis-related genes encoding p53, Bax, caspase-3, and c-Jun were upregulated after aphantoxin exposure, but there was no evidence of DNA laddering; apoptosis could take place by pathways independent of DNA fragmentation. These results demonstrate that aphantoxin exposure can cause cell death in zebrafish brain tissue, with low doses inducing apoptosis and higher doses inducing necrosis. PMID:21710505

Zhang, Delu; Hu, Chunxiang; Wang, Gaohong; Li, Dunhai; Li, Genbao; Liu, Yongding

2013-05-01

422

ANALYTICAL METHODOLOGY FOR THE DETERMINATION OF KEPONE (TRADEMARK) RESIDUES IN FISH, SHELLFISH, AND HI-VOL AIR FILTERS  

EPA Science Inventory

The recent discovery of the pollution of the environment with Kepone has resulted in a tremendous interest in the development of residue methodology for the compound. Current multiresidue methods for the determination of the common organochlorinated pesticides do not yield good q...

423

Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish: QPX, a Thraustochytrid-like Disease of Clams  

NSDL National Science Digital Library

This Canadian Fisheries and Oceans fact sheet features Quahog Parasite Unknown (QPX), a protistan parasite of the commercially exploited hard clam Mercenaria mercenaria. The fact sheet includes information about its common name, scientific name, geographic distribution, host species and impact, diagnostic techniques, and references.

S.M. Bower

424

Total and Inorganic Arsenic in Mid-Atlantic Marine Fish and Shellfish and Implications for Fish Advisories  

Microsoft Academic Search

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

Richard Greene; Eric A. Crecelius

2006-01-01

425

Total and Inorganic Arsenic in Mid-Atlantic Marine Fish and Shellfish and Implications for Fish Advisories  

SciTech Connect

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.

Greene, Richard; Crecelius, Eric A.

2006-02-06

426

Culture and behavior of selected estuarine fish and shellfish in aquaria receiving effluent water from a power plant  

Microsoft Academic Search

Sixteen species (2 molluscs, 2 crustaceans, and 12 fishes) were used as biological monitors in flow-through aquaria. The aquaria received effluent from Houston Lighting and Power Company's Cedar Bayou generating station located in Chambers County, Texas. Growth and survival of organisms were monitored in ambient and thermally regulated water (20, 25, and 30°C). Behavior experiments were carried out with several

1981-01-01

427

Accumulation, transformation and tissue distribution of domoic acid, the amnesic shellfish poisoning toxin, in the common cuttlefish, Sepia officinalis  

Microsoft Academic Search

Domoic acid (DA) is a phycotoxin produced by some diatoms, mainly from the Pseudo-nitzschia genus, and has been detected throughout the marine food web. Although DA has been frequently found in cephalopod prey such as crustaceans and fish, little is known about DA accumulation in these molluscs. This study presents the first data showing relevant concentrations of DA detected in

Pedro R. Costa; Rui Rosa; Alexandra Duarte-Silva; Vanda Brotas; Maria Antónia M. Sampayo

2005-01-01

428

Bacteria associated with false-positive most-probable-number coliform test results for shellfish and estuaries.  

PubMed Central

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

Hussong, D; Damaré, J M; Weiner, R M; Colwell, R R

1981-01-01

429

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...

430

Suppliers List for the Florida Shellfish Industry Revised: February 2010 by FDACS Division of Aquaculture (Dan Cavins)  

E-print Network

, Inc. 396 Berkley Avenue Ottawa, Canada K2A 2G6 Phone: (613) 722-3451 Ramsey's Printing & Office) 328-8080 Website: http://www.pallets.com #12;3 Graders / Tumblers Sheps Welding West Highway 345: (516) 653-6155 Anderson Machine & Welding 73 Division Street Holtsville, NY 11742 Phone: (516) 696

Florida, University of

431

Modelling shellfish growth with dynamic energy budget models: an application for cockles and mussels in the Oosterschelde (southwest Netherlands)  

PubMed Central

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

Troost, T. A.; Wijsman, J. W. M.; Saraiva, S.; Freitas, V.

2010-01-01

432

Modelling shellfish growth with dynamic energy budget models: an application for cockles and mussels in the Oosterschelde (southwest Netherlands).  

PubMed

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

Troost, T A; Wijsman, J W M; Saraiva, S; Freitas, V

2010-11-12

433

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...

434

Global Hindcasts and Future Projections of Coastal Nitrogen and Phosphorus Loads Due to Shellfish and Seaweed Aquaculture  

Microsoft Academic Search

A model was developed to estimate nitrogen and phosphorus budgets for aquaculture production of crustaceans, bivalves, gastropods, and seaweed, using country production data for the 1970–2006 period from the Food and Agriculture Organi- zation and scenarios based on the Millenium Assessment for 2006–2050. Global production of crustaceans (18% yr), molluscs (7.4%), and seaweed (8%) increased rapidly during the 1970–2006 period.

A. F. Bouwman; M. Paw?owski; C. Liu; A. H. W. Beusen; S. E. Shumway; P. M. Glibert; C. C. Overbeek

2011-01-01

435

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...

436

Climate change impacts on natural toxins in food production systems, exemplified by deoxynivalenol in wheat and diarrhetic shellfish toxins  

Microsoft Academic Search

Climate change is expected to affect food and feed safety, including the occurrence of natural toxins in primary crop and seafood production; however, to date, quantitative estimates are scarce. This study aimed to estimate the impact of climate change effects on mycotoxin contamination of cereal grains cultivated in the terrestrial area of north west Europe, and on the frequency of

H. J. van der Fels-Klerx; J. E. Olesen; L.-J. Naustvoll; Y. Friocourt; M. J. B. Mengelers; J. H. Christensen

2012-01-01

437

Journal of Shellfish Research, Vol. 25, No.1, 23-32, 2006. GROWTH RATE AND LONGEVITY OF DREISSENA POLYMORPHA (PALLAS)  

E-print Network

and longevity in zebra mussels (Dreissena polymorpha [Pallas]).These methods include: counting annual rings and longevity. KEY WORDS: zebra mussels, Dreissena polymorpha, growth, growth rate, methods, longevity INTRODUCTION The zebra mussel, Dreissena polymorpha (Pallas), is one of the most pervasive invaders

Padilla, Dianna

438

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 ...

439

Distribution of Vibrio species in Shellfish and Water Samples Collected from the Atlantic Coastline of South-East Nigeria  

PubMed Central

Crayfish, lobster, and sea-water samples collected from five fishing islands on the Atlantic coast–Bight of Biafra (Bonny)–belonging to Ibaka Local Government Area of Akwa-Ibom State of Nigeria were bacteriologically evaluated on thiosulphate citrate bile-salt sucrose (TCBS) agar for Vibrio load and pathotypes. Mean log10 Vibrio counts of 7.64±2.78 cfu/g (in crayfish), 5.07±3.21 cfu/g (in lobster), and 3.06±2.27 cfu/mL (in sea-water) were obtained in rainy season (June-July) while counts in the dry season (November-December) were 6.25±1.93 cfu/g, 5.99±1.54 cfu/g, and 3.84±1.78 cfu/mL respectively. The physicochemical measurements (temperature, pH, and total dissolved solutes) of the sea-water did not vary significantly in the two seasons across all five islands. Vibrio species isolated were Vibrio cholerae (both O1 and non-O1 serotypes), V. parahaemolyticus, V. vulnificus, V. mimicus, and V. fluvialis. Both Ogawa and Inaba subtypes of V. cholerae O1 serotype were found. In addition, the Hikojima subtype, which had not been previously reported in the region, was isolated in two samples. The results show that these Vibrio species are endemic in the area. PMID:24288944

Eyisi, Onyedikachukwu A.L.; Nwodo, Uchechukwu U.

2013-01-01

440

Cultivation of the benthic microalga Prorocentrum lima for the production of diarrhetic shellfish poisoning toxins in a vertical flat photobioreactor.  

PubMed

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

Wang, Shuai; Chen, Junhui; Li, Zhaoyong; Wang, Yanlong; Fu, Boqiang; Han, Xiaotian; Zheng, Li

2015-03-01

441

A new method for preconcentration and determination of mercury in fish, shellfish and saliva by cold vapour atomic absorption spectrometry.  

PubMed

The development of a method using solid phase extraction for preconcentration and determination of mercury by cold vapour atomic absorption spectrometry is described. Hg (II) ions are sorbed on a minicolumn packed with Amberlite XAD-4 sorbent functionalised with 2-(2'-benzothiazolylazo)-p-cresol (BTAC). Then, a reducing solution was used for desorption and the transport of the analyte for subsequent detection. The assay presented a limit of detection of 0.011 ?g L?¹ (0.011 ?g g?¹, for solid samples), a limit of quantification of 0.038 ?g L?¹ (0.038 ?g g?¹, for solid samples), a precision of 0.50% (1.000 ?g L?¹ Hg solution) and an enrichment factor of 46. The proposed method was applied to the determination of mercury in human saliva (0.055-0.200 ?g L?¹). The following seafood collected in Todos os Santos Bay, Brazil was also analysed: bass (0.169-0.195 ?g g?¹), mullet (0.043-0.361 ?g g?¹), shrimp (0.075-0.374 ?g g?¹) and mussel (0.206-0.397 ?g g?¹). PMID:24295696

Lemos, Valfredo Azevedo; dos Santos, Liz Oliveira

2014-04-15

442

Quantification of Hepatitis A Virus in Shellfish by Competitive Reverse Transcription-PCR with Coextraction of Standard RNA  

PubMed Central

To quantify hepatitis A virus (HAV) in experimentally contaminated mussels, we developed an internal standard RNA with a 7-nucleotide deletion for competitive reverse transcription (RT)-PCR. Deposited directly into the sample, this standard was used both as extraction control and as quantification tool. After coextraction and competitive RT-PCR, standard and wild-type products were detected by differential hybridization with specific probes and a DNA enzyme immunoassay. The quantifiable range with this reproducible method was 104 to 107 copies of HAV/gram or 400 to 106 50% tissue culture infective doses/ml. PMID:9872801

Arnal, Charlotte; Ferre-Aubineau, Virginie; Mignotte, Berangere; Imbert-Marcille, Berthe Marie; Billaudel, Sylviane

1999-01-01

443

75 FR 18549 - In the Matter of Certain Non-Shellfish Derived Glucosamine and Products Containing Same; Notice...  

Federal Register 2010, 2011, 2012, 2013, 2014

Notice is hereby given that the U.S. International Trade Commission has determined to affirm an initial determination (``ID'') (Order No. 26) granting a joint motion to terminate the investigation as to respondent Ethical Naturals, Inc. from the investigation based upon a settlement agreement. The investigation is...

2010-04-12

444

Global market: shellfish imports as a source of reemerging food-borne hepatitis A virus infections in Spain  

Microsoft Academic Search

.  A total of 16 mollusk imports from South America to Spain, including clam and scallop species, were analyzed for hepatitis\\u000a A virus (HAV), due to the great concern about this type of food after an important hepatitis A outbreak in eastern Spain in\\u000a September 1999. In addition, clams from the stock that had caused the outbreak were also tested. Of

J. Romalde; I. Torrado; C. Ribao; J. Barja

2001-01-01

445

INACTIVATION OF THE FISH PATHOGENS LACTOCOCCUS GARVIEAE AND INFECTIOUS PANCREATIC NECROSIS VIRUS IN AN AEROBIC COMPOSTING SILO INCORPORATING SHELLFISH  

Microsoft Academic Search

Composting and ensiling for the degradation of category 2 fish farm wastes with clinical disease is permitted under EC regulation 1774\\/2002 but for these processes technical data on the practical feasibility to inactivate common fish pathogens is required. In connection with the composting option, a field trial was organized to demonstrate the inactivation of two fish pathogens Lactococcus garvieae (L.

Smail DA; Garden A; Thompson F; Cronjé A; Heyworth A

446

BOTHRIOCEPHALUS - CHAPTER IN SUGGESTED PROCEDURES FOR THE DETECTION AND IDENTIFICATION OF CERTAIN FIN FISH AND SHELLFISH PATHOGENS. 5TH EDITION.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Asian tapeworm Bothriocephalus acheilognathi is an exotic parasite of fish that probably came into the United States with the importation of grass carp Ctenopharyngodon idella from Europe. It primarily infects minnows and carps (Cyprinidae) but also is found in fish from several other families....

447

Shellfish mariculture facility which employs passive solar heating and heat pump systems. Performance and cost analysis study. Final report  

SciTech Connect

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)

Zoto, G.A.; Krabach, M.H.

1984-06-01

448

77 FR 53164 - Magnuson-Stevens Fishery Conservation and Management Act Provisions; Fisheries of the...  

Federal Register 2010, 2011, 2012, 2013, 2014

...to cause paralytic shellfish poisoning. The proposed re-opening...that cause paralytic shellfish poisoning (PSP). The closure was implemented...on advice from the U.S. Food and Drug Administration...Bank. The paralytic shellfish poisoning (PSP) contaminated...

2012-08-31

449

Salt Marsh  

NSDL National Science Digital Library

High school level and higher description of Spartina salt marshes with pictures. Page is full of fantastic photographs most featuring a descriptive caption. Topics discussed include zonation, succession, and the intertidal zone. The habitat's associated flora and fauna are discussed. Organisms of particular interest include: Spartina alterniflora, Spartina patens, Geukenzia demissa, Mytilus edulis, Distichlis spicata, Salicornia, Melampus bidentatus, Ilyanassa obsoleta, and Hydrobia totteni.

450

Removal of Escherichia coli, Enterococcus fecalis, coliphage MS2, poliovirus, and hepatitis A virus from oysters ( Crassostrea virginica) and hard shell clams ( Mercinaria mercinaria) by depuration  

Microsoft Academic Search

Filter-feeding bivalve mollusks (shellfish) can bioaccumulate pathogenic microorganisms in up to 1000-fold higher levels than overlying waters, and therefore disease risks are associated with consuming raw or partially cooked shellfish. Many of these shellfish-borne diseases are due to enteric bacteria and viruses associated with fecal contamination. To control shellfish-borne diseases, guidelines for shellfish harvest waters and shellfish meat have been

David C. Love; Greg L. Lovelace; Mark D. Sobsey

2010-01-01

451

MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser  

E-print Network

. The presence of saxitoxin in coastal shellfish, which causes paralytic shellfish poisoning, was generally poisoning · Saxitoxin Resale or republication not permitted without written consent of the publisher OPENPEN

Oregon, University of

452

46 CFR 221.3 - Definitions.  

Code of Federal Regulations, 2012 CFR

...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls,...

2012-10-01

453

46 CFR 221.3 - Definitions.  

Code of Federal Regulations, 2014 CFR

...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls,...

2014-10-01

454

46 CFR 221.3 - Definitions.  

Code of Federal Regulations, 2011 CFR

...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls,...

2011-10-01

455

46 CFR 221.3 - Definitions.  

Code of Federal Regulations, 2010 CFR

...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls,...

2010-10-01

456

46 CFR 221.3 - Definitions.  

Code of Federal Regulations, 2013 CFR

...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls, shells...planting, cultivating, catching, taking, or harvesting of fish, shellfish, marine animals, pearls,...

2013-10-01

457

Studies on the feeding attractants for fishes and shellfishes. XXVI. Probable feeding attractants in allspice Pimenta officinalis for black abalone Haliotis discus  

Microsoft Academic Search

The attraction activity of allspice Pimenta officinalis was statistically estimated based on the exploratory and feeding behaviour of the black abalone Haliotis discus. The ether fraction (oils) from the water extract of allspice was the most attractive. The essential oil of allspice was separated into four fractions (phenolic, acidic, neutral and basic) by extraction using a mixture of pentane-dichloromethane (1:1,

Katsuhiko Harada; Taiko Miyasaki; Shigeyasu Kawashima; Haruyasu Shiota

1996-01-01

458

Run reconstruction and life-history model. Fish\\/shellfish study number 28. Exxon Valdez oil spill state\\/federal natural resource damage assessment final report  

Microsoft Academic Search

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

H. J. Geiger; W. D. Templin; J. S. Collie; T. J. Quinn

1995-01-01

459

Shellfish production in Washington is a $60 million a year industry. Several major pests plague this industry, resulting in major crop loss. One of the most important  

E-print Network

.cahnrs.wsu.edu/impacts #12;Japanese eelgrass: Funding was obtained from the Washington Department of Fish and Wildlife, and the Washington State Commission for Pesticide Registration. Research was conducted to assess ecological and economic impacts of Japanese eelgrass and develop new effective and safe tools for its control, white

Collins, Gary S.

460

English title: Estimation of the Cd intake in the human dietary from the shellfish caught in the seashore of Charente-Maritime (France)  

E-print Network

in the seashore of Charente-Maritime (France) French title: Estimation du taux de Cd dans l'alimentation humaine à partir de coquillages et crustacés ramassés dans les eaux littorales de la Charente- Maritime (France. 2 DDASS Charente Maritime, 2 Avenue Fétilly, F-17000 La Rochelle Email : pmiraman@univ-lr.fr hal

Paris-Sud XI, Université de