Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Exxon Valdez oil spill impacts lasting far longer than expected, scientists say

19.12.2003


Assuming that oil spills such as the one that devastated Alaska’s Prince William Sound almost 15 years ago and other toxic insults to the environment have only short-term impacts on coastal marine ecosystems has been a big mistake, a new study shows.



Oil’s negative effects last far longer, scientists now say, and the findings should be a wake-up call for better environmental research and protection.

The study, conducted by a University of North Carolina at Chapel Hill researcher and colleagues, involved synthesizing results of numerous more specialized but revealing investigations of the Alaskan disaster’s impact on various plant and animal species.


"These simply astounding findings have extremely important implications for environmental management," said principal investigator Dr. Charles H. Peterson, Alumni Distinguished professor of marine sciences at the University of North Carolina at Chapel Hill. "They show the environmental consequences of the Exxon Valdez oil spill went far beyond the more than 250,000 seabirds, thousands of marine mammals and countless numbers of other coastal marine organisms killed in the first days, weeks and months."

A report on the work appears in the Dec. 19 issue of the journal Science.

Besides Peterson, authors are Drs. Stanley D. Rice and Jeffrey W. Short of the National Marine Fisheries Service’s Auke Bay Laboratory at the Alaska Fisheries Science Center in Juneau; Dr. Daniel Esler of Canada’s Simon Fraser University in Burnaby, B.C.; Drs. James L. Bodkin and Brenda E. Ballachey of the U.S. Geological Survey’s Alaska Science Center in Anchorage; and Dr. David B. Irons of the U.S. Department of the Interior’s Fish and Wildlife Service in Anchorage.

"Studies we reviewed and synthesized showed that oil has persisted in surprisingly large quantities for years after the Exxon Valdez spill in subsurface reservoirs under course intertidal sediments," Peterson said. "This oil was sequestered in conditions where weathering by wave action, light and bacteria was inhibited, and toxicity remained for a decade or more."

As a result, many species suffered long-term loss, he said. For example, chronic exposure to the oil in mouths of streams boosted mortality among incubating pink salmon eggs for at least four years after the spill.

"Higher mortality was induced by concentrations of polycyclic aromatic hydrocarbons of only a few parts per billion," Peterson said. "These results require a complete reconsideration of the foundations of ecological risk assessment and ecotoxicology because acute mortality from oil involves concentrations perhaps 1,000 times greater. Earlier experiments incorrectly implied that lower oil concentrations were safe, which the new work clearly showed was not true."

Beyond their acute losses, marine mammals and sea ducks suffered high mortality for years after the accident in part because they ate invertebrates contaminated by the hidden oil and also contacted oil directly while digging up prey. Species as diverse as sea otters, harlequin ducks and killer whales suffered large, long-term losses. Oiled mussel beds and other tidal shoreline habitats will take an estimated 30 years to recover.

"Long-term declines also were observed in pink salmon as sublethal effects of oil exposure early in their life history led to stunted growth and indirect increases in mortality while they were in the ocean phase of their lives," he said.

Peterson said studies of the Exxon Valdez oil spill should lead to a new understanding of how lingering oil deposits affect species over many years, how sublethal, chronic doses compromise health, growth and reproduction and how impaired species interact negatively with one another in "cascade" fashion.

"Recognition that chronic exposures of fish eggs to oil concentrations as low as a few parts per billion lead indirectly to higher mortality shows the critical need to better control stormwater runoff of petroleum hydrocarbons and other toxins," he said. "In a developed country like the United States, an amount of petroleum equal to the Exxon Valdez oil spill is spilled annually for every 50 million people."

Revising and enforcing water quality standards and stormwater rules can help restore fisheries production lost to pollution, the scientist said.


Peterson works at the Institute of Marine Sciences, a part of UNC’s College of Arts and Sciences located in Morehead City, N.C.

Note: Peterson can be reached at (252) 726-6841, Ext. 130 or cpeters@email.unc.edu

David Williamson | EurekAlert!
Further information:
http://www.unc.edu/

More articles from Ecology, The Environment and Conservation:

nachricht Species may appear deceptively resilient to climate change
24.11.2017 | University of California - Davis

nachricht Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University

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: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>