Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Mercury releases contaminate ocean fish: Dartmouth-led effort publishes major findings

04.12.2012
New research important to discussion of international mercury

In new research published in a special issue of the journal Environmental Research and in "Sources to Seafood: Mercury Pollution in the Marine Environment"— a companion report by the Dartmouth-led Coastal and Marine Mercury Ecosystem Research Collaborative (C-MERC), scientists report that mercury released into the air and then deposited into oceans contaminates seafood commonly eaten by people in the U.S. and globally.

Over the past century, mercury pollution in the surface ocean has more than doubled, as a result of past and present human activities such as coal burning, mining, and other industrial processes. The research findings by C-MERC published today also examine the effects of local mercury inputs that dominate some near-shore coastal waters.

C-MERC's research is presented through nine scientific papers in Environmental Research and is the culmination of two years of work by approximately 70 mercury and marine scientists from multiple disciplines including biology, ecotoxicology, engineering, environmental geochemistry, and epidemiology. The research provides a synthesis of the science on the sources, fate, and human exposure to mercury in marine systems by tracing the pathways and transformation of mercury to methylmercury from sources to seafood to consumers.

Two other papers focusing on the health effects of methylmercury were published earlier this year in Environmental Health Perspectives. Methylmercury has long been known as a potent neurotoxicant, particularly as a result of acute and high level human exposures primarily through seafood consumption, but more recent research has revealed health effects at increasingly lower levels of exposure.

The companion report, "Sources to Seafood: Mercury Pollution in the Marine Environment," looks at the pathways and consequences of mercury pollution across marine systems by drawing on findings from the C-MERC papers, scientific literature, and data from a range of marine systems and coastal basins (See accompanying image). Specifically, the report examines mercury sources, pathways, and inputs for the Hudson River Estuary, San Francisco Bay, Gulf of Mexico, Long Island Sound, Chesapeake Bay, Gulf of Maine, Arctic Ocean, and the open ocean.

C-MERC's research findings are especially timely, as the U.S. and other nations prepare for the fifth session of the United Nations Environment Programme's Intergovernmental Negotiating Committee (INC5) on January 13-18, 2013 in Geneva, Switzerland, which is working to prepare a legally binding instrument to control mercury releases to the environment.

"Despite the fact that most people's mercury exposure is through the consumption of marine fish, this is the first time that scientists have worked together to synthesize what is known about how mercury moves from its various sources to different areas of the ocean and then up the food chain to the seafood most people eat," said Celia Y. Chen, Ph.D., Research Professor of Biological Sciences at Dartmouth. She is a co-author of the new Environmental Research papers on nutrient supply and mercury dynamics, and mercury sources in the Gulf of Maine, and authored an editorial on the subject in the journal, and is also a lead author of "Sources to Seafood." Chen will represent Dartmouth as an accredited non-governmental organization at INC5 in an observer status. Copies of C-MERC's Sources to Seafood report will be made available to INC5 attendees.

C-MERC research suggests that mercury deposited from the atmosphere ranges from 56% of the mercury loading to several large gulfs to approximately 90% in the open ocean.

"Oceans are home to large tuna and swordfish, which together account for more than half of the mercury intake from seafood for the overall U.S. population," said Elsie M. Sunderland, Assistant Professor of Aquatic Science at Harvard University. She is a lead author of an Environmental Research paper on mercury sources in the Gulf of Maine and a lead author of "Sources to Seafood."

Model estimates from the report indicate that methylmercury concentrations in marine fish will decline roughly in proportion to decreases in mercury inputs, though the timing of the response will vary.

"Our model estimates show that for the North Atlantic Ocean, a 20% cut in the amount of mercury deposited to the ocean from the atmosphere would lead to about a 16% decline in mercury levels in fish… But it is important to realize that achieving a 20% decrease in mercury deposition will require substantial cuts in current anthropogenic emissions, given the already very sizeable build-up of mercury in terrestrial environments and ocean waters," said Robert P. Mason, Ph.D., Professor of Marine Sciences at the University of Connecticut. Mason is a lead author of the Environmental Research paper on mercury biogeochemical cycling in the ocean and a lead author of "Sources to Seafood."

The C-MERC team also evaluated the fate of mercury in nearshore coastal waters and found a contrasting pattern to the oceans. "For some nearshore coastal waterbodies, like San Francisco Bay and the Hudson River Estuary, where there are large mercury sources such as historically contaminated sites, ongoing releases from wastewater or industrial waste and atmospheric mercury deposition in the watershed, mercury loading can be dominated by river inputs," said Charles T. Driscoll, Ph.D., University Professor of Environmental Systems Engineering at Syracuse University. He is a lead author on an Environmental Research paper on nutrient supply and mercury dynamics, and a lead author of "Sources to Seafood."

The C-MERC team estimates that river inputs can be as much as 80% of the total mercury inputs to some estuaries. "The impact of mercury released to coastal waters from watersheds via rivers has been a somewhat underappreciated aspect of the problem. Yet, these bays and estuaries can be important sources of fish for local anglers, thus controls on these sources can have substantial local benefits," explained Driscoll.

"C-MERC's synthesis of research identifies the most important drivers of mercury pollution to different oceans and coastal waters, and can help policymakers understand the links between environmental processes, methylmercury levels in marine ecosystems, human exposure, and the human health effects—all of which are critical to the discussion of how local, regional and global mercury pollution affects the world's supply of seafood," said Chen.

Approximately one-third of all mercury emissions are associated with current industrial sources and other human activities that can be controlled. "The good news is that the science suggests that if mercury inputs are curtailed, mercury levels in ocean fish will decline and decrease the need for warnings to limit consumption of this globally important food source," added Chen.

About the Coastal and Marine Mercury Ecosystem Research Collaborative (C-MERC)

In 2010, the Toxic Metals Superfund Research Program at Dartmouth College brought together an international group of scientists and policy stakeholders to establish the Coastal and Marine Mercury Ecosystem Research Collaborative (C-MERC). The goal was to review current knowledge - and knowledge gaps – relating to a global environmental health problem: mercury contamination of the world's marine fish. C-MERC participants attended two workshops over a two-year period, and in 2012, C-MERC authors published a series of peer-reviewed papers in the journals Environmental Health Perspectives and Environmental Research that elucidated key processes related to the inputs, cycling, and uptake of mercury in marine ecosystems, effects on human health, and policy implications. For more information, please visit: www.dartmouth.edu/~toxmetal/C-MERC/index.html

The translation of this research through C-MERC and "Sources to Seafood: Mercury Pollution in the Marine Environment" was made possible by the Superfund Research Program of the National Institute of Environmental Health Sciences of the National Institutes of Health under award number P42ES007373. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health.

Amy Olson | EurekAlert!
Further information:
http://www.dartmouth.edu
http://www.dartmouth.edu/~toxmetal/C-MERC/index.html

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Greifswalder Forscher dringen mit superauflösendem Mikroskop in zellulären Mikrokosmos ein

Das Institut für Anatomie und Zellbiologie weiht am Montag, 05.12.2016, mit einem wissenschaftlichen Symposium das erste Superresolution-Mikroskop in Greifswald ein. Das Forschungsmikroskop wurde von der Deutschen Forschungsgemeinschaft (DFG) und dem Land Mecklenburg-Vorpommern finanziert. Nun können die Greifswalder Wissenschaftler Strukturen bis zu einer Größe von einigen Millionstel Millimetern mittels Laserlicht sichtbar machen.

Weit über hundert Jahre lang galt die von Ernst Abbe 1873 publizierte Theorie zur Auflösungsgrenze von Lichtmikroskopen als ein in Stein gemeißeltes Gesetz....

Im Focus: Durchbruch in der Diabetesforschung: Pankreaszellen produzieren Insulin durch Malariamedikament

Artemisinine, eine zugelassene Wirkstoffgruppe gegen Malaria, wandelt Glukagon-produzierende Alpha-Zellen der Bauchspeicheldrüse (Pankreas) in insulinproduzierende Zellen um – genau die Zellen, die bei Typ-1-Diabetes geschädigt sind. Das haben Forscher des CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften im Rahmen einer internationalen Zusammenarbeit mit modernsten Einzelzell-Analysen herausgefunden. Ihre bahnbrechenden Ergebnisse werden in Cell publiziert und liefern eine vielversprechende Grundlage für neue Therapien gegen Typ-1 Diabetes.

Seit einigen Jahren hatten sich Forscher an diesem Kunstgriff versucht, der eine simple und elegante Heilung des Typ-1 Diabetes versprach: Die vom eigenen...

Im Focus: Makromoleküle: Mit Licht zu Präzisionspolymeren

Chemikern am Karlsruher Institut für Technologie (KIT) ist es gelungen, den Aufbau von Präzisionspolymeren durch lichtgetriebene chemische Reaktionen gezielt zu steuern. Das Verfahren ermöglicht die genaue, geplante Platzierung der Kettengliedern, den Monomeren, entlang von Polymerketten einheitlicher Länge. Die präzise aufgebauten Makromoleküle bilden festgelegte Eigenschaften aus und eignen sich möglicherweise als Informationsspeicher oder synthetische Biomoleküle. Über die neuartige Synthesereaktion berichten die Wissenschaftler nun in der Open Access Publikation Nature Communications. (DOI: 10.1038/NCOMMS13672)

Chemische Reaktionen lassen sich durch Einwirken von Licht bei Zimmertemperatur auslösen. Die Forscher am KIT nutzen diesen Effekt, um unter Licht die...

Im Focus: Neuer Sensor: Was im Inneren von Schneelawinen vor sich geht

Ein neuer Radarsensor erlaubt Einblicke in die inneren Vorgänge von Schneelawinen. Entwickelt haben ihn Ingenieure der Ruhr-Universität Bochum (RUB) um Dr. Christoph Baer und Timo Jaeschke gemeinsam mit Kollegen aus Innsbruck und Davos. Das Messsystem ist bereits an einem Testhang im Wallis installiert, wo das Schweizer Institut für Schnee- und Lawinenforschung im Winter 2016/17 Messungen damit durchführen möchte.

Die erhobenen Daten sollen in Simulationen einfließen, die das komplexe Geschehen im Inneren von Lawinen detailliert nachbilden. „Was genau passiert, wenn sich...

Im Focus: Neuer Rekord an BESSY II: 10 Millionen Ionen erstmals bis auf 7,4 Kelvin gekühlt

Magnetische Grundzustände von Nickel2-Ionen spektroskopisch ermittelt

Ein internationales Team aus Deutschland, Schweden und Japan hat einen neuen Temperaturrekord für sogenannte Quadrupol-Ionenfallen erreicht, in denen...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Von „Coopetition“ bis „Digitale Union“ – Die Fertigungsindustrien im digitalen Wandel

02.12.2016 | Veranstaltungen

Experten diskutieren Perspektiven schrumpfender Regionen

01.12.2016 | Veranstaltungen

Die Perspektiven der Genom-Editierung in der Landwirtschaft

01.12.2016 | Veranstaltungen

 
VideoLinks
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Parkinson-Krankheit und Dystonien: DFG-Forschergruppe eingerichtet

02.12.2016 | Förderungen Preise

Smart Data Transformation – Surfing the Big Wave

02.12.2016 | Studien Analysen

Nach der Befruchtung übernimmt die Eizelle die Führungsrolle

02.12.2016 | Biowissenschaften Chemie