Publications by authors named "Vera L Trainer"

41 Publications

Hiding in plain sight: Shellfish-killing phytoplankton in Washington State.

Harmful Algae 2021 05 7;105:102032. Epub 2021 Jun 7.

Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle WA 98112, United States.

Summer bivalve shellfish mortalities have been observed in Puget Sound for nearly a century and attempts to understand and mitigate these losses have been only partially successful. Likewise, the understanding of the environmental conditions triggering shellfish mortalities and successful strategies for their mitigation are incomplete. In the literature, phytoplankton have played only a cursory role in summer shellfish mortalities in Washington State because spawning stress and bacteria were thought to be the primary causes. In recent years, the occurrence of Protoceratium reticulatum (Claparede & Lachmann) Buetschli and Akashiwo sanguinea (Hirasaka) Hansen & Moestrup, have been documented by the SoundToxins research and monitoring partnership in increasing numbers and duration and have been associated with declining shellfish health or mortality at various sites in Puget Sound. Blooms of these species occur primarily in summer months and have been shown to cause mass mortalities of shellfish in the U.S. and other parts of the world. In 2016-2017, yessotoxins (YTX) were measured in several species of Puget Sound bivalve shellfish, with a maximum concentration of 2.20 mg/kg in blue mussels, a value below the regulatory limit of 3.75 mg/kg established by the European Union for human health protection but documented to cause shellfish mortalities in other locations around the world. In July 2019, a bloom of P. reticulatum coincided with a summer shellfish mortality event, involving a dramatic surfacing of stressed, gaping Manila clams, suggesting that YTX could be the cause. YTX concentrations in their tissues were measured at a maximum of 0.28 mg/kg and histology of these clams demonstrated damage to digestive glands. A culture of P. reticulatum, isolated from North Bay during this massive bloom and shellfish mortality event, showed YTX reaching 26.6 pg/cell, the highest recorded toxin quota measured in the U.S. to date. Concentrations of YTX in phytoplankton samples reached a maximum of 920 ng/L during a P. reticulatum bloom in Mystery Bay on 13 August 2019 when cell abundance reached 1.82 million cells/L. The highest cellular YTX quota during that bloom that lasted into September was 10.8 pg/cell on 3 Sept 2019. Shellfish producers in Washington State have also noted shellfish larvae mortalities due to A. sanguinea passing through filtration intake systems into hatchery facilities. Early warning of shellfish-killing harmful algal bloom (HAB) presence in Puget Sound, through partnerships such as SoundToxins, provides options for shellfish growers to mitigate their effects through early harvest, movement of shellstock to upland facilities, or enhanced filtration at aquaculture facilities.
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http://dx.doi.org/10.1016/j.hal.2021.102032DOI Listing
May 2021

Marine harmful algal blooms (HABs) in the United States: History, current status and future trends.

Harmful Algae 2021 02 3;102:101975. Epub 2021 Mar 3.

Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle, WA, 98112, United States.

Harmful algal blooms (HABs) are diverse phenomena involving multiple. species and classes of algae that occupy a broad range of habitats from lakes to oceans and produce a multiplicity of toxins or bioactive compounds that impact many different resources. Here, a review of the status of this complex array of marine HAB problems in the U.S. is presented, providing historical information and trends as well as future perspectives. The study relies on thirty years (1990-2019) of data in HAEDAT - the IOC-ICES-PICES Harmful Algal Event database, but also includes many other reports. At a qualitative level, the U.S. national HAB problem is far more extensive than was the case decades ago, with more toxic species and toxins to monitor, as well as a larger range of impacted resources and areas affected. Quantitatively, no significant trend is seen for paralytic shellfish toxin (PST) events over the study interval, though there is clear evidence of the expansion of the problem into new regions and the emergence of a species that produces PSTs in Florida - Pyrodinium bahamense. Amnesic shellfish toxin (AST) events have significantly increased in the U.S., with an overall pattern of frequent outbreaks on the West Coast, emerging, recurring outbreaks on the East Coast, and sporadic incidents in the Gulf of Mexico. Despite the long historical record of neurotoxic shellfish toxin (NST) events, no significant trend is observed over the past 30 years. The recent emergence of diarrhetic shellfish toxins (DSTs) in the U.S. began along the Gulf Coast in 2008 and expanded to the West and East Coasts, though no significant trend through time is seen since then. Ciguatoxin (CTX) events caused by Gambierdiscus dinoflagellates have long impacted tropical and subtropical locations in the U.S., but due to a lack of monitoring programs as well as under-reporting of illnesses, data on these events are not available for time series analysis. Geographic expansion of Gambierdiscus into temperate and non-endemic areas (e.g., northern Gulf of Mexico) is apparent, and fostered by ocean warming. HAB-related marine wildlife morbidity and mortality events appear to be increasing, with statistically significant increasing trends observed in marine mammal poisonings caused by ASTs along the coast of California and NSTs in Florida. Since their first occurrence in 1985 in New York, brown tides resulting from high-density blooms of Aureococcus have spread south to Delaware, Maryland, and Virginia, while those caused by Aureoumbra have spread from the Gulf Coast to the east coast of Florida. Blooms of Margalefidinium polykrikoides occurred in four locations in the U.S. from 1921-2001 but have appeared in more than 15  U.S. estuaries since then, with ocean warming implicated as a causative factor. Numerous blooms of toxic cyanobacteria have been documented in all 50  U.S. states and the transport of cyanotoxins from freshwater systems into marine coastal waters is a recently identified and potentially significant threat to public and ecosystem health. Taken together, there is a significant increasing trend in all HAB events in HAEDAT over the 30-year study interval. Part of this observed HAB expansion simply reflects a better realization of the true or historic scale of the problem, long obscured by inadequate monitoring. Other contributing factors include the dispersion of species to new areas, the discovery of new HAB poisoning syndromes or impacts, and the stimulatory effects of human activities like nutrient pollution, aquaculture expansion, and ocean warming, among others. One result of this multifaceted expansion is that many regions of the U.S. now face a daunting diversity of species and toxins, representing a significant and growing challenge to resource managers and public health officials in terms of toxins, regions, and time intervals to monitor, and necessitating new approaches to monitoring and management. Mobilization of funding and resources for research, monitoring and management of HABs requires accurate information on the scale and nature of the national problem. HAEDAT and other databases can be of great value in this regard but efforts are needed to expand and sustain the collection of data regionally and nationally.
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http://dx.doi.org/10.1016/j.hal.2021.101975DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8058451PMC
February 2021

Taking the Long View for Oceans and Human Health Connection through Community Driven Science.

Int J Environ Res Public Health 2021 03 6;18(5). Epub 2021 Mar 6.

Department of Fisheries, Quinault Indian Nation, Taholah, WA 98587, USA.

The most proactive approach to resolving current health and climate crises will require a long view, focused on establishing and fostering partnerships to identify and eliminate root causes of the disconnect between humans and nature. We describe the lessons learned through a unique scientific partnership that addresses a specific crisis, harmful algal blooms (HABs), along the northeast Pacific Ocean coast, that blends current-day technology with observational knowledge of Indigenous communities. This integrative scientific strategy resulted in creative solutions for forecasting and managing HAB risk in the Pacific Northwest as a part of the US Ocean and Human Health (OHH) program. Specific OHH projects focused on: (1) understanding genetic responses of tribal members to toxins in the marine environment, (2) knowledge sharing by elders during youth camps; (3) establishing an early warning program to alert resource managers of HABs are explicit examples of proactive strategies used to address environmental problems. The research and monitoring projects with tribal communities taught the collaborating non-Indigenous scientists the value of reciprocity, highlighting both the benefits from and protection of oceans that promote our well-being. Effective global oceans and human health initiatives require a collective action that gives equal respect to all voices to promote forward thinking solutions for ocean health.
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http://dx.doi.org/10.3390/ijerph18052662DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7967353PMC
March 2021

Temporal and spatial distribution of Azadinium species in the inland and coastal waters of the Pacific northwest in 2014-2018.

Harmful Algae 2020 09 5;98:101874. Epub 2020 Aug 5.

Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.

Azaspiracids, produced by some species of the dinoflagellate genera Azadinium and Amphidoma, can cause a syndrome in humans called azaspiracid shellfish poisoning (AZP). In 1995, mussels from the Irish west coast contaminated with azaspiracids were, for the first time, linked to this human illness that has symptoms of nausea, vomiting, severe diarrhea, and stomach cramps. The only confirmed cases of AZP to date in the United States occurred in Washington State in 2008 from mussels imported from Ireland. Shortly after this case, several others involving similar gastrointestinal symptoms were reported by shellfish consumers from Washington State. However, no detectable diarrhetic shellfish toxins or Vibrio contamination were found. Cursory analysis of Solid Phase Adsorption Toxin Tracking (SPATT) samplers suggested the presence of azaspiracids in Washington State waters and motivated a study to evaluate the presence and distribution of Azadinium species in the region. During the spring and summer months of 2014-2015, quantitative polymerase chain reaction (qPCR) analyses detected the presence of the toxigenic species Azadinium poporum and A. spinosum on the outer coast and throughout the inland waters of Washington State. In 2016-2018, standard curves developed using A. poporum isolated from Puget Sound and A. spinosum isolated from the North Sea were used to quantify abundances of up to 10,525 cells L of A. poporum and 156 cells L of A. spinosum at shore-based sites. Abundances up to 1,206 cells L of A. poporum and 30 cells L of A. spinosum were measured in the coastal waters of the Pacific Northwest in 2017. Other harmful genera, including Alexandrium, Dinophysis, and Pseudo-nitzschia, were observed using light microscopy at coastal sites where A. poporum was also observed. In some samples where both A. poporum and A. spinosum were absent, an Amphidomataceae-specific qPCR assay indicated that other species of Azadinium or Amphidoma were present. The identification of Azadinium species in the PNW demonstrates the need to assess their toxicity and to incorporate their routine detection in monitoring programs to aid resource managers in mitigating risks to azaspiracid shellfish poisoning in this region.
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http://dx.doi.org/10.1016/j.hal.2020.101874DOI Listing
September 2020

Future HAB science: Directions and challenges in a changing climate.

Harmful Algae 2020 01 30;91:101632. Epub 2019 Sep 30.

Environment and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.

There is increasing concern that accelerating environmental change attributed to human-induced warming of the planet may substantially alter the patterns, distribution and intensity of Harmful Algal Blooms (HABs). Changes in temperature, ocean acidification, precipitation, nutrient stress or availability, and the physical structure of the water column all influence the productivity, composition, and global range of phytoplankton assemblages, but large uncertainty remains about how integration of these climate drivers might shape future HABs. Presented here are the collective deliberations from a symposium on HABs and climate change where the research challenges to understanding potential linkages between HABs and climate were considered, along with new research directions to better define these linkages. In addition to the likely effects of physical (temperature, salinity, stratification, light, changing storm intensity), chemical (nutrients, ocean acidification), and biological (grazer) drivers on microalgae (senso lato), symposium participants explored more broadly the subjects of cyanobacterial HABs, benthic HABs, HAB effects on fisheries, HAB modelling challenges, and the contributions that molecular approaches can bring to HAB studies. There was consensus that alongside traditional research, HAB scientists must set new courses of research and practices to deliver the conceptual and quantitative advances required to forecast future HAB trends. These different practices encompass laboratory and field studies, long-term observational programs, retrospectives, as well as the study of socioeconomic drivers and linkages with aquaculture and fisheries. In anticipation of growing HAB problems, research on potential mitigation strategies should be a priority. It is recommended that a substantial portion of HAB research among laboratories be directed collectively at a small sub-set of HAB species and questions in order to fast-track advances in our understanding. Climate-driven changes in coastal oceanographic and ecological systems are becoming substantial, in some cases exacerbated by localized human activities. That, combined with the slow pace of decreasing global carbon emissions, signals the urgency for HAB scientists to accelerate efforts across disciplines to provide society with the necessary insights regarding future HAB trends.
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http://dx.doi.org/10.1016/j.hal.2019.101632DOI Listing
January 2020

Pelagic harmful algal blooms and climate change: Lessons from nature's experiments with extremes.

Harmful Algae 2020 01 3;91:101591. Epub 2019 May 3.

Estuary & Ocean Science Center, Romberg Tiburon Campus, San Francisco State University, 3150 Paradise Dr., Tiburon, CA 94920, USA.

Time series now have sufficient duration to determine harmful algal bloom (HAB) responses to changing climate conditions, including warming, stratification intensity, freshwater inputs and natural patterns of climate variability, such as the El Niño Southern Oscillation and Pacific Decadal Oscillation. Against the context of time series, such as those available from phytoplankton monitoring, dinoflagellate cyst records, the Continuous Plankton Recorder surveys, and shellfish toxin records, it is possible to identify extreme events that are significant departures from long-term means. Extreme weather events can mimic future climate conditions and provide a "dress rehearsal" for understanding future frequency, intensity and geographic extent of HABs. Three case studies of extreme HAB events are described in detail to explore the drivers and impacts of these oceanic outliers that may become more common in the future. One example is the chain-forming diatom of the genus Pseudo-nitzschia in the U.S. Pacific Northwest and its response to the 2014-16 northeast Pacific marine heat wave. The other two case studies are pelagic flagellates. Highly potent Alexandrium catenella group 1 dinoflagellate blooms (up to 150 mg/kg PST in mussels; 4 human poisonings) during 2012-17 created havoc for the seafood industry in Tasmania, south-eastern Australia, in a poorly monitored area where such problems were previously unknown. Early evidence suggests that changes in water column stratification during the cold winter-spring season are driving new blooms caused by a previously cryptic species. An expansion of Pseudochattonella cf. verruculosa to the south and A. catenella to the north over the past several years resulted in the convergence of both species to cause the most catastrophic event in the history of the Chilean aquaculture in the austral summer of 2016. Together, these two massive blooms were colloquially known as the "Godzilla-Red tide event", resulting in the largest fish farm mortality ever recorded worldwide, equivalent to an export loss of USD$800 million which when combined with shellfish toxicity, resulted in major social unrest and rioting. Both blooms were linked to the strong El Niño event and the positive phase of the Southern Annular Mode, the latter an indicator of anthropogenic climate change in the southeastern Pacific region. For each of these three examples, representing recent catastrophic events in geographically distinct regions, additional targeted monitoring was employed to improve the understanding of the climate drivers and mechanisms that gave rise to the event and to document the societal response. Scientists must be poised to study future extreme HAB events as these natural experiments provide unique opportunities to define and test multifactorial drivers of blooms.
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http://dx.doi.org/10.1016/j.hal.2019.03.009DOI Listing
January 2020

The effect of temperature and salinity on growth rate and azaspiracid cell quotas in two strains of Azadinium poporum (Dinophyceae) from Puget Sound, Washington State.

Harmful Algae 2019 11 23;89:101665. Epub 2019 Sep 23.

Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle, WA, 98112, USA. Electronic address:

Azaspiracids (AZA) are novel lipophilic polyether marine biotoxins associated with azaspiracid shellfish poisoning (AZP). Azaspiracid-59 (AZA-59) is a new AZA that was recently detected in strains of Azadinium poporum from Puget Sound, Washington State. In order to understand how environmental factors affect AZA abundances in Puget Sound, a laboratory experiment was conducted with two local strains of A. poporum to estimate the growth rate and AZA-59 (both intra- and extracellular) cell quotas along temperature and salinity gradients. Both strains of A. poporum grew across a wide range of temperatures (6.7 °C to 25.0 °C), and salinities (15 to 35). Growth rates increased with increasing temperature up to 20.0 °C, with a range from 0.10 d to 0.42 d. Both strains of A. poporum showed variable growth rates from 0.26 d to 0.38 d at salinities from 15 to 35. The percentage of intracellular AZA-59 in both strains was generally higher in exponential than in stationary phase along temperature and salinity gradients, indicating higher retention of toxin in actively growing cells. Cellular toxin quotas varied by strain in both the temperature and salinity treatments but were highest at the lowest growth rates, especially for the faster growing strain, NWFSC1011. Consistent with laboratory experiments, field investigations in Sequim Bay, WA, during 2016-2018 showed that A. poporum was detected when salinity and temperature became favorable to higher growth rates in June and July. Although current field data of A. poporum in Puget Sound indicate a generally low abundance, the potential of local A. poporum to adapt to and grow in a wide range of temperature and salinity may open future windows for blooms. Although increased temperatures, anticipated for the Puget Sound region over the next decades, will enhance the growth of A. poporum, these higher temperatures will not necessarily support higher toxin cell quotas. Additional sampling and assessment of the total toxicity of AZA-59 will provide the basis for a more accurate estimation of risk for azaspiracid poisoning in Puget Sound shellfish.
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http://dx.doi.org/10.1016/j.hal.2019.101665DOI Listing
November 2019

Dynamics of seagrass bed microbial communities in artificial Chattonella blooms: A laboratory microcosm study.

Harmful Algae 2019 04 6;84:139-150. Epub 2019 Apr 6.

Plankton Laboratory, Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho Hokkaido, Hakodate, 041-8611, Japan.

The influence of algicidal and growth-inhibiting bacteria in a seagrass (Zostera marina) bed, and their capability of controlling blooms of the fish-killing raphidophyte flagellate, Chattonella antiqua, were examined in laboratory microcosm experiments. Bacterial communities in seawater collected from the seagrass bed and Z. marina biofilm suppressed artificial Chattonella blooms in the presence of their natural competitors and predators. Phylogenetic analysis suggest that considerable numbers of bacteria that suppress Chattonella, including algicidal or growth-inhibiting bacteria isolated from seagrass biofilm and seawater from the seagrass bed, are members of Proteobacteria that can decompose lignocellulosic compounds. A direct comparison of partial 16S rRNA gene sequences (500 bp) revealed that the growth-limiting bacterium (strain ZM101) isolated from Z. marina biofilm belonged to the genus Phaeobacter (Alphaproteobacteria) showed 100% similarity with strains of growth-limiting bacteria isolated from seawater of both the seagrass bed and nearshore region, suggesting that the origin of these growth-limiting bacteria are the seagrass biofilm or seawater surrounding the seagrass bed. This study demonstrates that Chattonella growth-limiting bacteria living on seagrass biofilm and in the adjacent seawater can suppress Chattonella blooms, suggesting the possibility of Chattonella bloom prevention through restoration, protection, or introduction of seagrass in coastal areas.
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http://dx.doi.org/10.1016/j.hal.2018.12.004DOI Listing
April 2019

The successional formation and release of domoic acid in a Pseudo-nitzschia bloom in the Juan de Fuca Eddy: A drifter study.

Harmful Algae 2018 11 21;79:105-114. Epub 2018 Oct 21.

Department of Biology, Western University, London, Ontario, N6A 5B7, Canada.

Blooms of Pseudo-nitzschia species are frequent, but presently unpredictable, in the Juan de Fuca Eddy region off the coasts of Washington (US) and British Columbia (Canada). This upwelling eddy region is proposed to be the bloom commencement site, before cells are entrained into the coastal surface currents. During a shipboard study, we characterized the different stages of the Pseudo-nitzschia bloom development from its initiation and intensification, to its eventual sinking and dissipation. Specifically, we followed a water mass using lagrangian ARGOS-tracked drifters released at the eddy water mass and quantified production of dissolved and particulate domoic acid, and the physiological status of the Pseudo-nitzschia cells with regards to photosynthesis, nutrient needs and sinking rates, along with its relationship with competing species - in this case, the marine euglenoid, Eutreptiella spp. The drifter study allows for an interpretation of the presence or absence of Pseudo-nitzschia and domoic acid against active environmental factors - particularly copper and iron.
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http://dx.doi.org/10.1016/j.hal.2018.08.007DOI Listing
November 2018

Characterization of oceanic Noctiluca blooms not associated with hypoxia in the Northeastern Arabian Sea.

Harmful Algae 2018 04 11;74:46-57. Epub 2018 Apr 11.

Kerala University of Fisheries and Ocean Studies (KUFOS), Panangad P.O., Kochi, Kerala, 682506, India.

Intense blooms of the heterotrophic dinoflagellate, green Noctiluca scintillans, have been reported annually in the Northern Arabian Sea since the early 2000s. Although not known to produce organic toxins, these blooms are still categorized as a harmful due to their association with massive fish mortalities. Recent work has attributed these blooms to the vertical expansion of the oxygen minimum zone, driven by cultural eutrophication from major coastal cities in western India. As diatoms are preferred prey of green Noctiluca scintillans, more frequent blooms of this mixotroph will likely impact the productivity of important fisheries in the region. The present study uses a satellite algorithm to determine the distribution of both diatom and green Noctiluca blooms in the Northeastern Arabian Sea from 2009 to 2016. The results from shipboard microscopy of phytoplankton community composition were used to validate the satellite estimates. The satellite algorithm showed 76% accuracy for detection of green Noctiluca and 92% for diatoms. Shipboard measurements and data from biogeochemical-Argo floats were used to assess the relationship between oxygen concentrations and green Noctiluca blooms in the Northeastern Arabian Sea. Regardless of the presence of a Noctiluca bloom, the dissolved oxygen in the photic zone was always >70% saturated, with an average oxygen saturation >90%. The variability in the relative abundance of diatoms and green Noctiluca is not correlated with changes in oxygen concentration. These findings provide no evidence that cultural eutrophication has contributed to the decadal scale shifts in plankton composition in the Northeastern Arabian Sea oceanic waters. Conversely, the climatic warming of surface waters would have intensified stratification, thereby reducing net nutrient flux to the photic zone and decreasing silicate to nitrate ratios (Si:N); both factors that could increase the competitive advantage of the mixotroph, green Noctiluca, over diatoms. If so, the decadal-scale trajectory of phytoplankton community composition in the Northeastern Arabian Sea may be a harbinger of future climate-driven change in other productive oceanic systems.
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http://dx.doi.org/10.1016/j.hal.2018.03.008DOI Listing
April 2018

Identification of Azadinium species and a new azaspiracid from Azadinium poporum in Puget Sound, Washington State, USA.

Harmful Algae 2017 09 18;68:152-167. Epub 2017 Sep 18.

Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA. Electronic address:

The identification of a new suite of toxins, called azaspiracids (AZA), as the cause of human illnesses after the consumption of shellfish from the Irish west coast in 1995, resulted in interest in understanding the global distribution of these toxins and of species of the small dinoflagellate genus Azadinium, known to produce them. Clonal isolates of four species of Azadinium, A. poporum, A. cuneatum, A. obesum and A. dalianense were obtained from incubated sediment samples collected from Puget Sound, Washington State in 2016. These Azadinium species were identified using morphological characteristics confirmed by molecular phylogeny. Whereas AZA could not be detected in any strains of A. obesum, A. cuneatum and A. dalianense, all four strains of A. poporum produced a new azaspiracid toxin, based on LC-MS analysis, named AZA-59. The presence of AZA-59 was confirmed at low levels in situ using a solid phase resin deployed at several stations along the coastlines of Puget Sound. Using a combination of molecular methods for species detection and solid phase resin deployment to target shellfish monitoring of toxin at high-risk sites, the risk of azaspiracid shellfish poisoning can be minimized.
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http://dx.doi.org/10.1016/j.hal.2017.08.004DOI Listing
September 2017

Microsatellite Markers for Population Genetic Applications in the Domoic Acid-producing Diatom Pseudo-nitzschia australis Frenguelli (Bacillariophyceae).

Protist 2017 04 26;168(2):197-205. Epub 2017 Jan 26.

Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Boulevard East, Seattle, Washington, 98112, USA.

Microsatellites are commonly used markers in population genetics and are increasingly being employed to determine population structure in phytoplankton populations. We have developed seven polymorphic microsatellite markers for the domoic-acid producing diatom Pseudo-nitzschia australis. Using these markers, thirty P. australis isolates were genotyped, 10 isolates were from Monterey Bay, California and 20 were from off the northern coast of Oregon. The number of alleles per locus ranged from two to eight and observed heterozygosities ranged from 0.11 to 0.70. All but two of the isolates were genetically distinct and initial population differentiation analysis indicated no significant differences between the Pacific Northwest isolates and the Monterey Bay isolates. Pseudo-nitzschia australis microsatellites appear to be species specific based on cross amplification tests with Pseudo-nitzschia fraudulenta (Cleve) Hasle, Pseudo-nitzschia seriata (Cleve) H.Peragallo, Pseudo-nitzschia pungens (Grunow ex Cleve) and Pseudo-nitzschia multiseries (Hasle) Hasle.
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http://dx.doi.org/10.1016/j.protis.2017.01.002DOI Listing
April 2017

Algicidal and growth-inhibiting bacteria associated with seagrass and macroalgae beds in Puget Sound, WA, USA.

Harmful Algae 2017 02 3;62:136-147. Epub 2016 Aug 3.

Plankton Laboratory, Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate, Hokkaido, 041-8611, Japan. Electronic address:

The algicidal and growth-inhibiting bacteria associated with seagrasses and macroalgae were characterized during the summer of 2012 and 2013 throughout Puget Sound, WA, USA. In 2012, Heterosigma akashiwo-killing bacteria were observed in concentrations of 2.8×10CFUg wet in the outer organic layer (biofilm) on the common eelgrass (Zostera marina) in north Padilla Bay. Bacteria that inhibited the growth of Alexandrium tamarense were detected within the biofilm formed on the eelgrass canopy at Dumas Bay and North Bay at densities of ∼10CFUg wet weight. Additionally, up to 4100CFUmL of algicidal and growth-inhibiting bacteria affecting both A. tamarense and H. akashiwo were detected in seawater adjacent to seven different eelgrass beds. In 2013, H. akashiwo-killing bacteria were found on Z. marina and Ulva lactuca with the highest densities of ∼10CFUg wet weight at Shallow Bay, Sucia Island. Bacteria that inhibited the growth of H. akashiwo and A. tamarense were also detected on Z. marina and Z. japonica at central Padilla Bay. Heterosigma akashiwo cysts were detected at a concentration of 3400cystsg wet weight in the sediment from Westcott Bay (northern San Juan Island), a location where eelgrass disappeared in 2002. These findings provide new insights on the ecology of algicidal and growth-inhibiting bacteria, and suggest that seagrass and macroalgae provide an environment that may influence the abundance of harmful algae in this region. This work highlights the importance of protection and restoration of native seagrasses and macroalgae in nearshore environments, in particular those regions where shellfish restoration initiatives are in place to satisfy a growing demand for seafood.
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http://dx.doi.org/10.1016/j.hal.2016.04.004DOI Listing
February 2017

Climatic regulation of the neurotoxin domoic acid.

Proc Natl Acad Sci U S A 2017 01 9;114(2):239-244. Epub 2017 Jan 9.

College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331.

Domoic acid is a potent neurotoxin produced by certain marine microalgae that can accumulate in the foodweb, posing a health threat to human seafood consumers and wildlife in coastal regions worldwide. Evidence of climatic regulation of domoic acid in shellfish over the past 20 y in the Northern California Current regime is shown. The timing of elevated domoic acid is strongly related to warm phases of the Pacific Decadal Oscillation and the Oceanic Niño Index, an indicator of El Niño events. Ocean conditions in the northeast Pacific that are associated with warm phases of these indices, including changes in prevailing currents and advection of anomalously warm water masses onto the continental shelf, are hypothesized to contribute to increases in this toxin. We present an applied domoic acid risk assessment model for the US West Coast based on combined climatic and local variables. Evidence of regional- to basin-scale controls on domoic acid has not previously been presented. Our findings have implications in coastal zones worldwide that are affected by this toxin and are particularly relevant given the increased frequency of anomalously warm ocean conditions.
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http://dx.doi.org/10.1073/pnas.1606798114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5240689PMC
January 2017

An unprecedented coastwide toxic algal bloom linked to anomalous ocean conditions.

Geophys Res Lett 2016 Oct 9;43(19):10366-10376. Epub 2016 Oct 9.

Northwest Fisheries Science Center, National Marine Fisheries Service National Oceanic and Atmospheric Administration Seattle Washington USA.

A coastwide bloom of the toxigenic diatom in spring 2015 resulted in the largest recorded outbreak of the neurotoxin, domoic acid, along the North American west coast. Elevated toxins were measured in numerous stranded marine mammals and resulted in geographically extensive and prolonged closures of razor clam, rock crab, and Dungeness crab fisheries. We demonstrate that this outbreak was initiated by anomalously warm ocean conditions. thrived north of its typical range in the warm, nutrient-poor water that spanned the northeast Pacific in early 2015. The seasonal transition to upwelling provided the nutrients necessary for a large-scale bloom; a series of spring storms delivered the bloom to the coast. Laboratory and field experiments confirming maximum growth rates with elevated temperatures and enhanced toxin production with nutrient enrichment, together with a retrospective analysis of toxic events, demonstrate the potential for similarly devastating ecological and economic disruptions in the future.
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http://dx.doi.org/10.1002/2016GL070023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129552PMC
October 2016

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

Harmful Algae 2016 Jul;57(B):26-34

Marine Biotoxins Program, Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, Washington 98112 United States.

The Makah Tribe of Neah Bay, Washington, has historically relied on the subsistence harvest of coastal seafood, including shellfish, which remains an important cultural and ceremonial resource. Tribal legend describes visitors from other tribes that died from eating shellfish collected on Makah lands. These deaths were believed to be caused by paralytic shellfish poisoning, a human illness caused by ingestion of shellfish contaminated with saxitoxins, which are produced by toxin-producing marine dinoflagellates on which the shellfish feed. These paralytic shellfish toxins include saxitoxin, a potent Na channel antagonist that binds to the pore region of voltage gated Na channels. Amino acid mutations in the Na channel pore have been demonstrated to confer resistance to saxitoxin in softshell clam populations exposed to paralytic shellfish toxins present in their environment. Because of the notion of resistance to paralytic shellfish toxins, we aimed to determine if a resistance strategy was possible in humans with historical exposure to toxins in shellfish. We collected, extracted and purified DNA from buccal swabs of 83 volunteer Makah tribal members and sequenced the skeletal muscle Na channel (Na1.4) at nine loci to characterize potential mutations in the relevant saxitoxin binding regions. No mutations of these specific regions were identified after comparison to a reference sequence. This study suggests that any resistance of Makah Tribal members to saxitoxin is not a function of Na1.4 modification but may be due to mutations in neuronal or cardiac sodium channels or some other mechanism unrelated to sodium channel function.
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http://dx.doi.org/10.1016/j.hal.2016.03.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5015773PMC
July 2016

Environmental dynamics of red Noctiluca scintillans bloom in tropical coastal waters.

Mar Pollut Bull 2016 Oct 19;111(1-2):277-286. Epub 2016 Jul 19.

Indian National Centre for Ocean Information Services (INCOIS), Ocean Valley, Pragathi Nagar (BO), Nizampet (SO), Hyderabad 500090.

An intense bloom of red Noctiluca scintillans (NS) occurred off the Rushikulya estuarine region along the east coast of India, an important site for mass nesting events of the vulnerable Olive Ridley sea turtle. At its peak, densities of NS were 3.3×10(5) cells-l(-1), with low relative abundance of other phytoplankton. The peak bloom coincided with high abundance of gelatinous planktivores which may have facilitated bloom development by their grazing on other zooplankton, particularly copepods. Ammonium concentrations increased by approximately 4-fold in the later stages of bloom, coincident with stable NS abundance and chlorophyll concentrations in the nano- and microplankton. This increase likely was attributable to release of intracellular ammonium accumulated through NS grazing. Dissolved oxygen concentrations decreased in sub-surface waters to near hypoxia. Micro-phytoplankton increasingly dominated chlorophyll-a biomass as the bloom declined, with diminishing picoplankton abundance likely the result of high predation by the ciliate Mesodinium rubrum. Together, these data illustrate factors that can disrupt ecosystem balance in this critically important Indian coastal region.
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http://dx.doi.org/10.1016/j.marpolbul.2016.06.103DOI Listing
October 2016

Case diagnosis and characterization of suspected paralytic shellfish poisoning in Alaska.

Harmful Algae 2016 07 30;57(Pt B):45-50. Epub 2016 Aug 30.

Emergency Response Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA. Electronic address:

Clinical cases of paralytic shellfish poisoning (PSP) are common in Alaska, and result from human consumption of shellfish contaminated with saxitoxin (STX) and its analogues. Diagnosis of PSP is presumptive and based on recent ingestion of shellfish and presence of manifestations consistent with symptoms of PSP; diagnosis is confirmed by detection of paralytic shellfish toxins in a clinical specimen or food sample. A clinical diagnostic analytical method using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to evaluate the diagnosis of saxitoxin-induced PSP (STX-PSP) in 11 Alaskan patients using urine specimens collected between June 2010 and November 2011. Concentrations of urinary STX were corrected for creatinine concentrations to account for dilution or concentration of urine from water intake or restriction, respectively. Of the 11 patients with suspected PSP, four patients were confirmed to have STX-PSP by urine testing (24-364ng STX/g creatinine). Five patients had clinical manifestations of PSP though no STX was detected in their urine. Two patients were ruled out for STX-PSP based on non-detected urinary STX and the absence of clinical findings. Results revealed that dysphagia and dysarthria may be stronger indicators of PSP than paresthesia and nausea, which are commonly used to clinically diagnose patients with PSP. PSP can also occur from exposure to a number of STX congeners, such as gonyautoxins, however their presence in urine was not assessed in this investigation. In addition, meal remnants obtained from six presumptive PSP cases were analyzed using the Association of Official Analytical Chemists' mouse bioassay. All six samples tested positive for PSP toxins. In the future, the clinical diagnostic method can be used in conjunction with the mouse bioassay or HPLC-MS/MS to assess the extent of STX-PSP in Alaska where it has been suggested that PSP is underreported.
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http://dx.doi.org/10.1016/j.hal.2016.03.006DOI Listing
July 2016

Perception of risk for domoic acid related health problems: A cross-cultural study.

Harmful Algae 2016 07 30;57(Pt B):39-44. Epub 2016 Aug 30.

Department of Medicine, College of Medicine, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Box 100009, Gainesville, FL 32610, USA. Electronic address:

Risk perception is a complex process that refers to the way people approach, think about, and interpret risks in their environment. An important element of risk perception is that it is culturally situated. Since HABs can present a health risk in many places around the world, looking at cultural parameters for understanding and interpreting risks is important. This study examined how two different groups of people perceive the potential health risks of low-level exposure to domoic acid (DA) through razor clam consumption. The risk perceptions of Washington State, USA coastal dwelling Native American nations (NA) were compared to that of a community sample of recreational razor clam harvesters (CRH). Overall, the findings support the hypothesis that cultural and community specific contexts impact the perception of risk of a DA related illness. Specifically, the NA sample was distinguished from the CRH group in particular, by their worries about ocean pollution, attribution of DA risks to climate change, concerns about the potential impact of DA on future generations, and feeling of being better informed than the CRH group. The CRH group was more likely to attribute the DA problem to anthropogenic or industrial causes and view the risk of health problems from DA as lower than those associated with smoking, high cholesterol, anxiety or depression, alcoholism, high blood pressure or obesity. The CRH group was also more likely to turn to the media for DA-related information. Both groups trusted the decisions of state and tribe health and natural resources officials, and demonstrated a complex pattern of findings that involved gender. In summary, risk communication and outreach activities should be designed to take into consideration the specific factors that are unique to each cultural community.
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http://dx.doi.org/10.1016/j.hal.2016.03.007DOI Listing
July 2016

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

Harmful Algae 2016 07 30;57(Pt B):26-34. Epub 2016 Aug 30.

Marine Biotoxins Program, Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA 98112, United States.

The Makah Tribe of Neah Bay, Washington, has historically relied on the subsistence harvest of coastal seafood, including shellfish, which remains an important cultural and ceremonial resource. Tribal legend describes visitors from other tribes that died from eating shellfish collected on Makah lands. These deaths were believed to be caused by paralytic shellfish poisoning, a human illness caused by ingestion of shellfish contaminated with saxitoxins, which are produced by toxin-producing marine dinoflagellates on which the shellfish feed. These paralytic shellfish toxins include saxitoxin, a potent Na channel antagonist that binds to the pore region of voltage gated Na channels. Amino acid mutations in the Na channel pore have been demonstrated to confer resistance to saxitoxin in softshell clam populations exposed to paralytic shellfish toxins present in their environment. Because of the notion of resistance to paralytic shellfish toxins, the study aimed to determine if a resistance strategy was possible in humans with historical exposure to toxins in shellfish. We collected, extracted and purified DNA from buccal swabs of 83 volunteer Makah tribal members and sequenced the skeletal muscle Na channel (Nav1.4) at nine loci to characterize potential mutations in the relevant saxitoxin binding regions. No mutations of these specific regions were identified after comparison to a reference sequence. This study suggests that any resistance of Makah tribal members to saxitoxin, if present, is not a function of Nav1.4 modification, but may be due to mutations in neuronal or cardiac sodium channels, or some other mechanism unrelated to sodium channel function.
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http://dx.doi.org/10.1016/j.hal.2016.03.008DOI Listing
July 2016

The association between razor clam consumption and memory in the CoASTAL cohort.

Harmful Algae 2016 07 30;57(Pt B):20-25. Epub 2016 Aug 30.

Department of Medicine, College of Medicine, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Box 100009, Gainesville, FL 32610, USA. Electronic address:

This study represents a preliminary effort to examine the potential impacts of chronic, low level domoic acid (DA) exposure on memory in the CoASTAL cohort over the first four years of data collection (Wave 1). Five hundred and thirteen adult men and women representing three Native American Tribes were studied annually with standard measures of cognition and razor clam consumption (a known vector of DA exposure) over a four-year period. In addition, a pilot metric of DA concentration exposure was used which took into consideration average DA concentration levels in source beaches, as well as the amount consumed. Based upon generalized estimating equations (GEE) analysis, controlling for age, sex, race, year, education level, tribe, and employment status, findings indicated that high razor clam consumers (15 or more per month) had isolated decrements on some measures of memory (p=0.02-0.03), with other cognitive functions unaffected. The relatively lower memory scores were still within normal limits, and were thus not clinically significant. The pilot DA exposure metric had no association with any other aspect of cognition or behavior. There is a possible association between long-term, low-level exposure to DA through heavy razor clam consumption and memory functioning.
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http://dx.doi.org/10.1016/j.hal.2016.03.011DOI Listing
July 2016

Preface.

Harmful Algae 2016 07 30;57(Pt B). Epub 2016 Aug 30.

Marine Biotoxins Program, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA. Electronic address:

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http://dx.doi.org/10.1016/j.hal.2016.05.002DOI Listing
July 2016

The effects of salinity on the cellular permeability and cytotoxicity of Heterosigma akashiwo.

J Phycol 2016 10 12;52(5):745-760. Epub 2016 Aug 12.

Department of Biology, Western University, London, Ontario, Canada, N6A 5B7.

A laboratory study using the fish-killing raphidophyte Heterosigma akashiwo was conducted to examine its capability to grow at salinities below oceanic, and to test the perceived relationship between reduced salinities and increased cytotoxicity. A nonaxenic strain of H. akashiwo isolated from the U.S. Pacific Northwest was exposed to a combination of three salinity (32, 20, and 10) and five temperature (14.7°C, 18.4°C, 21.4°C, 24.4°C and 27.8°C) conditions. Our results demonstrate that cell permeability and cytotoxicity are strongly correlated in unialgal cultures of H. akashiwo, which both increased as salinity decreased from 32 to 10. Furthermore, over a broad median range of salinities (10 and 20), neither temperature nor specific growth rate was correlated with cytotoxicity. However, in cultures grown at the salinity of 32, both temperature and specific growth rate were inversely proportional to toxicity; this relationship was likely due to the effect of contamination by an unidentified species of Skeletonema in those cultures. The presence of Skeletonema sp. resulted in a cytotoxic response from H. akashiwo that was greater than the response caused by salinity alone. These laboratory results reveal the capability of H. akashiwo to become more toxic not only at reduced salinities but also in competition with another algal species. Changes in cell permeability in response to salinity may be an acclimation mechanism by which H. akashiwo is able to respond rapidly to different salinities. Furthermore, due to its strong positive correlation with cytotoxicity, cellular permeability is potentially associated with the ichthyotoxic pathway of this raphytophyte.
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http://dx.doi.org/10.1111/jpy.12433DOI Listing
October 2016

Effects of temperature and salinity on the growth of Alexandrium (Dinophyceae) isolates from the Salish Sea.

J Phycol 2016 Apr 25;52(2):230-8. Epub 2016 Feb 25.

Marine Biotoxins Program, Environmental and Fisheries Science Division, Northwest Fisheries Science Center, Seattle, Washington, USA.

Toxin-producing blooms of dinoflagellates in the genus Alexandrium have plagued the inhabitants of the Salish Sea for centuries. Yet the environmental conditions that promote accelerated growth of this organism, a producer of paralytic shellfish toxins, is lacking. This study quantitatively determined the growth response of two Alexandrium isolates to a range of temperatures and salinities, factors that will strongly respond to future climate change scenarios. An empirical equation, derived from observed growth rates describing the temperature and salinity dependence of growth, was used to hindcast bloom risk. Hindcasting was achieved by comparing predicted growth rates, calculated from in situ temperature and salinity data from Quartermaster Harbor, with corresponding Alexandrium cell counts and shellfish toxin data. The greatest bloom risk, defined at μ >0.25 d(-1) , generally occurred from April through November annually; however, growth rates rarely fell below 0.10 d(-1) . Except for a few occasions, Alexandrium cells were only observed during the periods of highest bloom risk and paralytic shellfish toxins above the regulatory limit always fell within the periods of predicted bloom occurrence. While acknowledging that Alexandrium growth rates are affected by other abiotic and biotic factors, such as grazing pressure and nutrient availability, the use of this empirical growth function to predict higher risk time frames for blooms and toxic shellfish within the Salish Sea provides the groundwork for a more comprehensive biological model of Alexandrium bloom dynamics in the region and will enhance our ability to forecast blooms in the Salish Sea under future climate change scenarios.
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http://dx.doi.org/10.1111/jpy.12386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4818979PMC
April 2016

Harmful algal blooms and climate change: Learning from the past and present to forecast the future.

Harmful Algae 2015 Nov 22;49:68-93. Epub 2015 Sep 22.

Romberg Tiburon Center for Environmental Studies, San Francisco State University, 3152 Paradise Drive, Tiburon, CA 94920-1205, USA.

Climate change pressures will influence marine planktonic systems globally, and it is conceivable that harmful algal blooms may increase in frequency and severity. These pressures will be manifest as alterations in temperature, stratification, light, ocean acidification, precipitation-induced nutrient inputs, and grazing, but absence of fundamental knowledge of the mechanisms driving harmful algal blooms frustrates most hope of forecasting their future prevalence. Summarized here is the consensus of a recent workshop held to address what currently is known and not known about the environmental conditions that favor initiation and maintenance of harmful algal blooms. There is expectation that harmful algal bloom (HAB) geographical domains should expand in some cases, as will seasonal windows of opportunity for harmful algal blooms at higher latitudes. Nonetheless there is only basic information to speculate upon which regions or habitats HAB species may be the most resilient or susceptible. Moreover, current research strategies are not well suited to inform these fundamental linkages. There is a critical absence of tenable hypotheses for how climate pressures mechanistically affect HAB species, and the lack of uniform experimental protocols limits the quantitative cross-investigation comparisons essential to advancement. A HAB "best practices" manual would help foster more uniform research strategies and protocols, and selection of a small target list of model HAB species or isolates for study would greatly promote the accumulation of knowledge. Despite the need to focus on keystone species, more studies need to address strain variability within species, their responses under multifactorial conditions, and the retrospective analyses of long-term plankton and cyst core data; research topics that are departures from the norm. Examples of some fundamental unknowns include how larger and more frequent extreme weather events may break down natural biogeographic barriers, how stratification may enhance or diminish HAB events, how trace nutrients (metals, vitamins) influence cell toxicity, and how grazing pressures may leverage, or mitigate HAB development. There is an absence of high quality time-series data in most regions currently experiencing HAB outbreaks, and little if any data from regions expected to develop HAB events in the future. A subset of observer sites is recommended to help develop stronger linkages among global, national, and regional climate change and HAB observation programs, providing fundamental datasets for investigating global changes in the prevalence of harmful algal blooms. Forecasting changes in HAB patterns over the next few decades will depend critically upon considering harmful algal blooms within the competitive context of plankton communities, and linking these insights to ecosystem, oceanographic and climate models. From a broader perspective, the nexus of HAB science and the social sciences of harmful algal blooms is inadequate and prevents quantitative assessment of impacts of future HAB changes on human well-being. These and other fundamental changes in HAB research will be necessary if HAB science is to obtain compelling evidence that climate change has caused alterations in HAB distributions, prevalence or character, and to develop the theoretical, experimental, and empirical evidence explaining the mechanisms underpinning these ecological shifts.
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http://dx.doi.org/10.1016/j.hal.2015.07.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4800334PMC
November 2015

Environmental influences on the seasonal distribution of Vibrio parahaemolyticus in the Pacific Northwest of the USA.

FEMS Microbiol Ecol 2015 Dec 9;91(12). Epub 2015 Oct 9.

Hollings Marine Laboratory, National Ocean Service, National Oceanic and Atmospheric Administration, 331 Fort Johnson Road, Charleston, SC 29412, USA.

Populations of Vibrio parahaemolyticus in the environment can be influenced by numerous factors. We assessed the correlation of total (tl+) and potentially virulent (tdh+) V. parahaemolyticus in water with three harmful algal bloom (HAB) genera (Pseudo-nitzschia, Alexandrium and Dinophysis), the abundance of diatoms and dinoflagellates, chlorophyll-a and temperature, salinity and macronutrients at five sites in Washington State from 2008-2009. The variability in V. parahaemolyticus density was explained predominantly by strong seasonal trends where maximum densities occurred in June, 2 months prior to the highest seasonal water temperature. In spite of large geographic differences in temperature, salinity and nutrients, there was little evidence of corresponding differences in V. parahaemolyticus density. In addition, there was no evident relationship between V. parahaemolyticus and indices of HAB genera, perhaps due to a lack of significant HAB events during the sampling period. The only nutrient significantly associated with V. parahaemolyticus density after accounting for the seasonal trend was silicate. This negative relationship may be caused by a shift in cell wall structure for some diatom species to a chitinous substrate preferred by V. parahaemolyticus. Results from our study differ from those in other regions corroborating previous findings that environmental factors that trigger vibrio and HAB events may differ depending on geographic locations. Therefore caution should be used when applying results from one region to another.
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http://dx.doi.org/10.1093/femsec/fiv121DOI Listing
December 2015

Integrative monitoring of marine and freshwater harmful algae in Washington State for public health protection.

Toxins (Basel) 2015 Apr 9;7(4):1206-34. Epub 2015 Apr 9.

Washington State Department of Health, Olympia, WA 98504, USA.

The more frequent occurrence of both marine and freshwater toxic algal blooms and recent problems with new toxic events have increased the risk for illness and negatively impacted sustainable public access to safe shellfish and recreational waters in Washington State. Marine toxins that affect safe shellfish harvest in the state are the saxitoxins that cause paralytic shellfish poisoning (PSP), domoic acid that causes amnesic shellfish poisoning (ASP) and the first ever US closure in 2011 due to diarrhetic shellfish toxins that cause diarrhetic shellfish poisoning (DSP). Likewise, the freshwater toxins microcystins, anatoxin-a, cylindrospermopsins, and saxitoxins have been measured in state lakes, although cylindrospermopsins have not yet been measured above state regulatory guidance levels. This increased incidence of harmful algal blooms (HABs) has necessitated the partnering of state regulatory programs with citizen and user-fee sponsored monitoring efforts such as SoundToxins, the Olympic Region Harmful Algal Bloom (ORHAB) partnership and the state's freshwater harmful algal bloom passive (opportunistic) surveillance program that allow citizens to share their observations with scientists. Through such integrated programs that provide an effective interface between formalized state and federal programs and observations by the general public, county staff and trained citizen volunteers, the best possible early warning systems can be instituted for surveillance of known HABs, as well as for the reporting and diagnosis of unusual events that may impact the future health of oceans, lakes, wildlife, and humans.
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http://dx.doi.org/10.3390/toxins7041206DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4417964PMC
April 2015

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

Mar Drugs 2013 Sep 30;11(10):3718-34. Epub 2013 Sep 30.

NOAA, Northwest Fisheries Science Center, Marine Biotoxins Laboratory, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.

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.
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http://dx.doi.org/10.3390/md11103718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3826131PMC
September 2013

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

Mar Drugs 2013 May 28;11(6):1815-35. Epub 2013 May 28.

Marine Biotoxins Program, Environmental Conservation Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E, Seattle, WA 98112, USA.

The illness of three people in 2011 after their ingestion of mussels collected from Sequim Bay State Park, Washington State, USA, demonstrated the need to monitor diarrhetic shellfish toxins (DSTs) in Washington State for the protection of human health. Following these cases of diarrhetic shellfish poisoning, monitoring for DSTs in Washington State became formalized in 2012, guided by routine monitoring of Dinophysis species by the SoundToxins program in Puget Sound and the Olympic Region Harmful Algal Bloom (ORHAB) partnership on the outer Washington State coast. Here we show that the DSTs at concentrations above the guidance level of 16 μg okadaic acid (OA) + dinophysistoxins (DTXs)/100 g shellfish tissue were widespread in sentinel mussels throughout Puget Sound in summer 2012 and included harvest closures of California mussel, varnish clam, manila clam and Pacific oyster. Concentrations of toxins in Pacific oyster and manila clam were often at least half those measured in blue mussels at the same site. The primary toxin isomer in shellfish and plankton samples was dinophysistoxin-1 (DTX-1) with D. acuminata as the primary Dinophysis species. Other lipophilic toxins in shellfish were pectenotoxin-2 (PTX-2) and yessotoxin (YTX) with azaspiracid-2 (AZA-2) also measured in phytoplankton samples. Okadaic acid, azaspiracid-1 (AZA-1) and azaspiracid-3 (AZA-3) were all below the levels of detection by liquid chromatography tandem mass spectrometry (LC-MS/MS). A shellfish closure at Ruby Beach, Washington, was the first ever noted on the Washington State Pacific coast due to DSTs. The greater than average Fraser River flow during the summers of 2011 and 2012 may have provided an environment conducive to dinoflagellates and played a role in the prevalence of toxigenic Dinophysis in Puget Sound.
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http://dx.doi.org/10.3390/md11061815DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3721207PMC
May 2013

In situ strain-level detection and identification of Vibrio parahaemolyticus using surface-enhanced Raman spectroscopy.

Anal Chem 2013 Mar 20;85(5):2630-7. Epub 2013 Feb 20.

Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States.

The outer membrane of a bacterium is composed of chemical and biological components that carry specific molecular information related to strains, growth stages, expressions to stimulation, and maybe even geographic differences. In this work, we demonstrate that the biochemical information embedded in the outer membrane can be used for rapid detection and identification of pathogenic bacteria using surface-enhanced Raman spectroscopy (SERS). We used seven different strains of the marine pathogen Vibrio parahaemolyticus as a model system. The strains represent four genetically distinct clades isolated from clinical and environmental sources in Washington, U.S.A. The unique quasi-3D (Q3D) plasmonic nanostructure arrays, optimized using finite-difference time-domain (FDTD) calculations, were used as SERS-active substrates for sensitive and reproducible detection of these bacteria. SERS barcodes were generated on the basis of SERS spectra and were used to successfully detect individual strains in both blind samples and mixtures. The sensing and detection methods developed in this work could have broad applications in the areas of environmental monitoring, biomedical diagnostics, and homeland security.
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http://dx.doi.org/10.1021/ac3021888DOI Listing
March 2013
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