Mercury in the Puget Sound food web: factors influencing body burdens in multiple species.

Mercury is a contaminant of concern in aquatic organisms world-wide. These biota are exposed to mercury from both natural emissions and human-caused sources. The Washington Department of Ecology has implemented a Chemical Action Plan (CAP) campaign to virtually eliminate the human-caused sources of mercury in Washington. The Washington Department of Fish and Wildlife’s Puget Sound Ecosystem Monitoring Program (PSEMP) - Toxics in Biota team has assessed the geographic extent and magnitude of mercury and other chemical contaminants in 18 fish and macroinvertebrates species across Puget Sound since 1989. In this report we compare total mercury concentrations in over 2000 samples from multiple fish and macroinvertebrate species to evaluate where in the food web mercury may be elevated, and which life history characteristics are associated with elevated body burdens. Characteristics we tested included age, trophic level, tissue lipid content, gender and proximity to known mercury sources (i.e., urbanized locations or elevated sediment mercury concentration). The highest mercury concentrations (greater than 0.50 mg/kg, wet wt.) occurred in sixgill sharks (Hexanchus griseus) an apex predator, and long-lived rockfishes (Sebastes spp.), especially in urban locations. Mean mercury concentrations were less than 0.17 mg/kg, wet wt. for all other species, but also varied with age and proximity to contaminant source. For example, most of the variability in muscle mercury concentrations of English sole (Parophrys vetulus) was explained by age and sediment mercury concentration. We also compared the concentration of mono-methyl mercury to total mercury for a subset of 220 samples, representing a range of species and tissues. Overall the majority of mercury (\u3e90%) was methylated, though there were notable exceptions. These data provide a solid basis for understanding the factors influencing mercury accumulation in the Puget Sound food web and serve as baseline data to evaluate the effectiveness of the Washington’s mercury CAP

Contaminants of emerging concern in bay mussels throughout the Salish Sea

Monitoring of bay mussels (Mytilus trossulus) has been an important part of WDFW’s Toxics-focused Biological Observation System (TBiOS) in the Puget Sound. Traditional monitoring has focused on a suite of priority compounds including PAHs, PCBs, PBDEs, and metals. In order to expand the range of compounds investigated, we undertook a pilot program in 2016 to analyze a select set of tissue samples for contaminants of emerging concern (CECs), utilizing two distinct analytical approaches. One set was analyzed by targeted methods focusing on a suite of over 200 pharmaceuticals, personal care products, and endocrine disrupting compounds. The results supported the notion of widespread exposure of marine organisms to trace levels of organic contaminants, including compounds such as the antidepressant sertraline, and the antibiotic virginiamycin. They also clearly demonstrated the importance of analytical considerations such as matrix effects, variable limits of detection, and quality assurance criteria when expanding and comparing these results across an ecosystem. A second set of tissue samples were analyzed by high resolution mass spectrometry (HRMS) in order to gain a broader understanding of exposures without focusing on a pre-defined list of analytes. This non-targeted approach utilized accurate mass, isotopic ratios, and retention time information for the tentative identification of a wide range of unique compounds for follow up analysis. Additional criteria, such as differential occurrence patterns, potential for biological interactions, and/or compound properties (e.g., halogenation), are then applied to identify a subset for focused identification. In this instance a candidate list of approximately 175 unique compounds was selected for identification based on common occurrence across samples and presence in existing accurate mass databases and libraries. These results again support the notion of a wide range of CEC exposures in the nearshore of Puget Sound, including synthetic hormones such as drospirenone

Assessing the threat of toxic contaminants to early marine survival of Chinook salmon in the Salish Sea

Human development of the Salish Sea has resulted in loss and modification of salmonid habitats, including reduced habitat quality due to contaminant inputs, particularly in the lower reaches of rivers and estuaries of the central Puget Sound. Chemical contaminants released into the Salish Sea from anthropogenic sources can reduce the health and productivity of salmon. Juvenile salmon are exposed to contaminants in freshwater, estuarine, and marine habitats but they are particularly vulnernable as they transition from fresh to saltwater because this life history stage is especially sensitive to stressors that may reduce their early marine survival. Reduced growth and disease resistance have been demonstrated for juvenile Chinook salmon exposed to environmentally relevant contaminant levels; however, synoptic, Puget Sound-wide surveys to assess the extent and magnitude of contaminant exposure are lacking. In this study we measured exposure of juvenile Chinook salmon to chemicals of concern that enter Puget Sound via stormwater, wastewater treatment facilities, atmospheric deposition to marine waters, and groundwater. During the spring and summer of 2013, outmigrating fish were sampled from the river mouthes and two adjacent marine shorelines at each of five Puget Sound river-estuary systems: Skagit, Snohomish, Green/Duwamish, Puyallup/Hylebos, and Nisqually. We (1) report the extent and magnitude of exposure, (2) compare exposure in outmigrants across five major river-estuary systems, and (3) evaluate potential effects on marine survival. Results will be used to establish a time series of contaminant conditions in juvenile Chinook salmon to measure the effectiveness of current toxics reductions strategies and actions, inform future pollution reduction efforts, and enhanced recovery of Chinook salmon

Input of PBDE exposure in juvenile Chinook salmon along their out-migrant pathway through the Snohomish River, WA

Polybrominated diphenyl ether (PBDE) flame retardant inputs to Puget Sound may be impairing the health of juvenile Chinook salmon and reducing their early marine survival in the Salish Sea, possibly contributing to their decline and limiting their recovery. Previous studies have shown Chinook salmon outmigrating from the Snohomish River accumulate PBDEs at concentrations high enough to alter their immune response, increasing their susceptibility to naturally occurring diseases; however, the source of PBDEs is unknown. Our study objective was to determine where in the Snohomish River system migrating Chinook salmon are exposed to and accumulate PBDEs, and to assess the source so that corrective actions can be implemented. Levels of PBDEs and other persistent organic pollutants were measured in salmon from the upstream tributaries of the Snoqualmie and Skykomish regions, representing the cumulative exposure from all sources prior to entering the Snohomish River, and were compared to those in salmon from subsequent downstream regions of the mainstem to assess where salmon are exposed and the exposure source. Additionally, contaminant levels were measured in salmon sampled from distributary channels of the lower delta to evaluate the extent of PBDE exposure in the outmigrating Snohomish River population. Analyses of the contaminant and body burden data reveal that juvenile Chinook salmon are primarily exposed to and accumulate PBDEs at two sites within the lower delta of the Snohomish River, both located in the immediate vicinity of a wastewater treatment plant outfall. Identification of the region within the Snohomish watershed where salmon are most exposed to PBDEs, as well as the source, allows environmental managers to establish corrective actions to control PBDE inputs. Ultimately, reductions in PBDE exposure should improve the health of Chinook salmon and enhance their marine survival

Evaluating a Prioritization Framework for Monitoring Chemicals of Emerging Concern in the Salish Sea Based on Lessons Learned from Western States Programs

We are now approaching a tipping point where priority pollutants may no longer be the primary driver of environmental impairment. Contaminants of Emerging Concern (CECs) present a challenge to environmental monitoring and management programs because the rapidly emerging state of the knowledge requires an adaptive and transparent prioritization framework. The state of the science, treatment technologies, and regulatory policies are not well understood, CEC quantification is challenging and expensive, and the management approach is not simply a concentration based criteria, but may include biological end-points. The need for a shared responsibility and leveraging across many programs was evaluated through a series of webinars with other programs studying CECs including Columbia River Toxics Program, Washington Department of Ecology, Oregon Department of Environmental Quality, Southern California Coastal Waters Research Project, and San Francisco Bay Regional Monitoring Program. The lessons learned were articulated into a 10-step prioritization framework. The critical lesson learned included: 1) Develop clear objectives, definitions of CECs, and target audience; 2) Identify conceptual models to provide a clear target for the appropriate media to monitor for various chemicals and at what frequency; 3) Define the chemical characteristics in terms of usage, persistence, bioaccumulation, and toxicity; 4) Develop a target CEC analyte list; 5) Screen and rank the CEC analyte list based on chemical characteristics, environmental concentrations, and state of the science; 6) Create a transparent prioritization process to include input from key stakeholders and end users that builds consensus during development; 7) Prioritize the chemical categories by using specific metrics such as available data, status of analytical methods, available thresholds, costs, programmatic concerns and opportunities for leveraging with other programs; 8) Identify potential biological end-points and other indicators; 9) Create a formal review process to support data and knowledge sharing, adaptively manage prioritization to include new science and critical research gaps; and 10) Develop a working group to facilitate leveraging of funds across many programs

An Ecosystem Framework for use in Recovery and Management of the Puget Sound Ecosystem: Linking Assessments of Ecosystem Condition to Threats and Management Strategies

The ongoing influx of people to the Puget Sound basin has placed pressure on the ecosystem and contributed to a decline in ecosystem health. The Puget Sound Partnership (Partnership), formed in July 2007, is leading an effort to restore the health of Puget Sound. The Partnership is taking an ecosystem-based approach to management that will, over time, address policy questions associated with multiple interacting ecosystem goals. As a foundation of this approach, indicators of ecosystem condition are used to describe a healthy Puget Sound, to evaluate progress towards meeting the recovery goals, to evaluate and adapt management strategies, and as the basis for reporting back to the public. A portfolio of high-level ecological and human health indicators, “vital signs,” was developed and adopted in 2011. Since then, the indicators have received external review by the WA State Academy of Sciences, scientists, planners, decision-makers, and other stakeholders. In response, the Partnership is evolving its portfolio of indicators in order to provide a broader set of indicators to track progress toward threat reductions and ecosystem recovery. To guide the indicator evolution process, we developed an overall organizing ecosystem framework that is an amalgamation of three frameworks: (1) a generalized “causal chain/network framework” that is used to link drivers and pressures of ecosystem health with (2) a framework for assessment of the condition of Puget Sound’s biophysical system, and (3) a framework for the condition of human well-being (HWB). Assessing a complete array of condition and driver/pressure indicators can aid the analysis of the causal mechanisms underlying compromised ecosystem condition. Moreover, in this framework, HWB is recognized as an outcome of biophysical condition as well as a driver of biophysical condition, and that its many components are differentially affected by and can affect conservation outcomes. This paper will present examples of how the Partnership, working with the Puget Sound Ecosystem Monitoring Program, is using this ecosystem framework to identify key ecosystem attributes and associated indicators for major ecosystem components. These biophysical condition indicators, along with indicators of key pressures on the system and indicators of HWB, can be used adaptively to track the recovery of Puget Sound

Effects of polycyclic aromatic hydrocarbons (PAHs) on Pacific herring (Clupea pallasii) embryos exposed to creosote-treated pilings related to a piling removal project in Quilcene Bay, Washington

Fish embryos spawned in Puget Sound nearshore marine habitats face a risk of exposure to a wide variety of toxic chemical pollutants during their incubation. Of particular concern are polycyclic aromatic hydrocarbons (PAHs), chemicals originating from oil spills, combusted fossil fuels, and creosote-treated pilings (CTPs). Removal of CTPs and prohibiting their use in marine waters are two recovery practices aimed at reducing PAHs and other creosote-related chemicals in marine waters. We used manually spawned and field-deployed Pacific herring embryos as a sensitive indicator of PAH exposure from CTPs, to test the efficacy of a CTP removal project in Quilcene Bay Washington. Embryos were deployed near CTPs in a 100-year-old derelict CTP field (1) before the CTPs were removed, (2) just after the removal process, to evaluate whether PAHs were released during removal, and (3) one year later, to evaluate whether PAHs lingered after CTP removal. Embryos incubated in the undisturbed CTP field prior to CTP removal exhibited PAH body burdens approximately five times higher than at reference areas, though total PAHs in the CTP-field embryos were below health effects thresholds. The CTP removal project was not fully completed during this study; CTP debris remained in the piling field and many CTPs were cut at the seafloor, resulting in freshly exposed CTP surfaces after the removal project ended. PAH concentrations in embryos sampled during and after CTP removal were 25x to 83x higher than reference embryos, and many exceeded health effects thresholds. PAH concentrations in embryos after CTP removal correlated with distance from former CTP locations. In addition, expression of cyp1a, a gene involved in PAH-detoxification, was correlated with PAH body burden. These results link embryo health with toxic contaminants associated with CTPs and illustrate the importance of fastidious adherence to appropriate CTP removal protocols to avoid contaminant risks to biota

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Toxic contaminants and other chemical tracers in Pacific herring and Pacific salmon provide insights into prey preferences and foraging habitat of southern resident killer whales

Knowledge of the foraging habitats and diets of endangered marine species is necessary to define and protect their critical habitat, but such information is often lacking, especially for highly mobile species. Stable isotopes and persistent organic pollutants (POPs) can be used as chemical tracers to infer foraging habitats and diet preferences of marine species. Stable isotopes of nitrogen and carbon are often used to infer trophic levels and inshore/offshore foraging habitats of marine species, while the relative concentrations classes of POPs can reflect time foraging in marine regions with distinct chemical inputs. In this study we used a combination of POPs and stable isotopes as chemical tracers to compare foraging habitats and marine distribution of Pacific herring (Clupea pallasii) and Chinook salmon (Oncorhynchus tshawytscha) along the west coast of North America, and to infer diet preferences of southern resident killer whales (Orcinus orca). The relative abundance of four POP classes in herring and salmon populations provided unique chemical fingerprints associated with their marine distribution and exposure to contaminated prey. For example, we observed relatively high levels of DDTs in Pacific herring and Chinook salmon populations originating from California that migrate and feed northward off the coast of California and Oregon, reflecting greater use of DDT pesticide in that region. We used an analysis of the POP and stable isotope patterns among herring, salmon, and whale populations to describe the relative distribution of these species in their foraging habitats and to evaluate prey preferences of three pods of southern resident killer whales

Biomagnification, oceanographic processes, and the distribution of toxic contaminants in Puget Sound’s pelagic food web

Long-term monitoring of toxic contaminants in fish has shown that Puget Sound’s pelagic food web is a regional hot spot of persistent, bioaccumulative, and toxic chemicals. Chemicals such as polychlorinated biphenyls (PCBs) are accumulated in and magnified by the pelagic food web, resulting in high concentrations in resident piscivorous fishes, salmon, and apex predators including killer whales. In this talk we underscore the importance of biomagnification of PCBs in the lowest trophic levels of the pelagic food web, and compare PCB biomagnification patterns across four of Puget Sound’s oceanographic basins. PCB data from phytoplankton, primary consumers, and resident fish predators lend credence to the hypothesis that PCBs concentrate in the pelagic food web as they enter surface waters, challenging the paradigm of preferential accumulation in sediments. Four potentially contributing factors are considered: Puget Sound’s microbial food web and abundant micro-grazers promote remineralization and recycling of organic material in surface waters, reducing the intensity of the benthic-pelagic coupling, Puget Sound’s fjord-like basins are deep enough to support vertically migrating zooplankton such as krill, which intercept and feed on sinking particles; krill feeding behavior mechanically breaks up particles and reduces their sinking rate, promoting retention of particle-bound PCBs in mid- and surface waters, a long pelagic food chain including vertically migrating zooplankton and a complex microbial community increases biomagnification potential, and sinking particles aggregate at the pycnocline in stratified waters, where they are processed by micro-grazers, and particulate PCBs are recycled by micro-grazers into the pelagic food web. These factors are discussed, using Elliott Bay as an example representing one of Puget Sound’s greatest sources of PCB contamination. Elliott Bay also has a history of large blooms of micro-grazers (Noctiluca sp.), it is deep enough to support vertically migrating zooplankton such as krill (Euphausia pacifica), and its waters can be strongly stratified