News Release
U.S. Department of the Interior
U.S. Geological Survey
Contact: Denver Makle, 703-648-4732, dmakle@xxxxxxxx
Editor's Note: Please email media@xxxxxxxxxxxxxxx to arrange interviews prior to or during conference activities. Please note specific content related to the abstracts and presentations at the Eighth International Conference on Mercury as a Global Pollutant will remain strictly embargoed until the day of the scientific session.
USGS at 2006 International Mercury Conference
The U.S. Geological Survey (USGS), in partnership with the University of Wisconsin-Madison, UW Sea Grant, and the University of Wisconsin-La Crosse, will host the Eighth Annual Conference on Mercury as a Global Pollutant conference at Monona Terrace Community and Convention Center in Madison, Wisconsin, Aug. 6-11.
Scientists from the USGS will discuss research on critical issues concerning mercury in the environment, including mercury found in volcanoes, streams, fish, and bird eggs.
Special Note: USGS scientist David Krabbenhoft is the conference co-chair, and also a contributing author for several sessions and the presenting author for the poster session, W-124: Mercury Mass Fluxes from the Lake 658 Watershed, which will be held on Wednesday, August 9, during 10:00 a.m. - 1:00 p.m. Krabbenhoft will be available for interviews.
Other USGS presentations include:
Monday, Aug. 7
Shedding Some Light on Mercury Lamps: How much mercury is used in mercury-containing lamps, such as fluorescent lamps and lamps used for roadway and parking-lot lighting? Mercury use in the lamp sector has decreased by about 30 percent since 1996 because the mercury per lamp requirement has fallen by nearly 60 percent since then. Average lamp mercury content is about 7 mg, which is much less than the 40 mg content of lamps in the 1980s. Mercury use per lamp may be reaching the low technological limit, but the use of mercury-containing lamps is increasing. The 7-ton U.S. lamp sector mercury flow is not large compared to other annual mercury flows in the United States--compare to 70 tons for U.S. coal burning. To find out more, attend the platform session, S-766: Mercury Flows through the Mercury-Containing Lamp Sector of the Economy of the United States on Monday, August 7, at 1:00 p.m. in Meeting Rooms K-Q. Presenter: Thomas Goonan (goonan@xxxxxxxx).
Mercury Rising or Falling? Mercury has not been mined as a principle product in the U.S. since 1992. Instead, mercury is obtained through reclamation or recycling from used mercury-containing products, such as automobile switches, dental amalgam, fluorescent lamps, medical uses, thermometers, and thermostats, or it is obtained as a byproduct from gold-silver processing in Nevada. In the 1990s, U.S. manufacturers used 500-600 metric tons of mercury annually, but now it is estimated at 200 metric tons or less. Mercury prices also are changing, for example, the price of mercury rose from $150 per flask in fall 2003 to $800 per flask in fall 2005. This rise in prices is due to a dwindling supply of mercury-containing devices and the rise in gold prices. In the United States, the leading end-user of mercury is the chlorine-caustic soda industry. Impending closure of these plants and the shift to non-mercury technology could ultimately result in a significant volume of mercury for recycling, sale or storage. To find out more, attend the platform session, S-1204: Mercury Recycling in the United States on Monday, August 7, at 5:00 p.m. in Meeting Rooms K-Q. Presenter: William E. Brooks (wbrooks@xxxxxxxx).
Tuesday, Aug. 8
Mercury Goes With the Flow: There may only be a small amount of mercury that enters stream water, but it's still a significant amount. So how does mercury get into stream water and how does it move once it's there? In Vermont streams, USGS studied the sources and forms of mercury; how mercury moves from watershed to streams; and how and where mercury methylation occurs in the upland landscape. In both headwater and larger Vermont streams, USGS found that there is a common source of mercury and methylmercury--most likely from forest litter and soil organic matter that is washed into streams by surface runoff and subsurface storm flow. To find out more, attend the platform session, S-1262: Mercury on the Move - Sources and Processes Driving Mercury and Methylmercury Export by Streamwater on Tuesday, August 8, at 2:40 p.m. in Ballroom A. Presenter: James B. Shanley (jshanley@xxxxxxxx).
Cracking the Case of Mercury in Bird Eggs: Protecting bird eggs may help protect other wildlife, but how? Since many birds are among the most vulnerable wildlife to mercury pollution, and embryos seem to be the life stage most sensitive to mercury, it is thought if mercury control regulations are set to protect the most sensitive bird embryos, then other wildlife are likely to be protected as well. Currently, captive breeding studies with mallards show that harmful thresholds of mercury in eggs are as little as .8 parts per million of mercury. But how much mercury is harmful in the eggs of wild species? USGS scientists collected wild bird eggs from the field and injected them with known concentrations of methylmercury. Results showed that the embryos of some species of wild birds are more sensitive to injected methylmercury than are the embryos of the mallard. Therefore, harmful thresholds of mercury established for mallard eggs may not mean that those thresholds will protect all wild bird eggs. To find out more, attend the platform session, S-261: Toxicological Significance of Mercury Levels in Bird Eggs: Knowns and Unknowns on Tuesday, August 8, at 3:00 p.m. in Ballroom B. Presenter: Gary Heinz (gheinz@xxxxxxxx).
Mapping Mercury in the United States: Where is the United States vulnerable to future mercury contamination? The USGS has identified water quality indicators of mercury vulnerability to predict the areas where methylmercury production is most likely to take place if inorganic mercury is present. The main water quality indicators include total organic carbon, pH, and sulfate. Using information sources including USGS water chemistry data from over 55,000 sites and 2500 watersheds, the USGS created a mercury vulnerability map. The map shows strong geographic trends in the eastern United States, with the highest vulnerability along the Gulf of Mexico and Atlantic coasts, in the Adirondacks, and in the Great Lakes region. The western United States has some watersheds with high predicted vulnerability, but no geographic pattern is evident. To find out more, attend the platform session, S-463: Mapping Modeled National-Scale Vulnerability to Mercury Loading across the United States: New Use for Nationally Available and Consistent Aquatic and Terrestrial Datasets on Tuesday, August 8, at 4:40 p.m. in Meeting Rooms K-Q. Presenter: Nathaniel Booth (nlbooth@xxxxxxxx).
Wednesday, Aug. 9
Mercury Rising Out of Volcanoes and Geothermal Systems: To find out how much mercury is emitted from volcanoes and geothermal systems, the USGS measured and scaled gas emission estimates from several volcanic, hotspot, and extensional geothermal systems and used historic data to estimate emissions from volcanoes. USGS found that volcanic geothermal systems, out of the different geothermal systems, emit the highest annual amount of mercury. Direct volcanic gas emissions in the conterminous United States are primarily emitted from the Cascade Range volcanoes, with Mount St. Helens being the most significant source of mercury emissions. The USGS estimated mercury emissions during different eruptive phases of Mount St. Helens, from 1980-2005. These data suggest that volcanic mercury emissions from Mount St. Helens are negligible during non-eruptive years, but estimates during eruptive years are highly variable. This suggests that volcanic mercury emissions for the conterminous United States are only significant to the national mercury budget during volcanic eruptions. To find out more, attend the poster session, W-87: Estimating Mercury Emissions from and Volcanoes for the Conterminous United States (S-EB-4: Biogeochemical Controls on Mercury in Geothermal Systems) on Wednesday, August 9, during 10:00 a.m. - 1:00 p.m. Presenter: Mark Engle (engle@xxxxxxxx).
Mercury Lurking in Yellowstone: How much mercury is lurking in Yellowstone National Park? The USGS collected 183 samples from hot springs, geysers, overflow drainages, and the Gibbon River in Yellowstone National Park during 2001-2005 to determine the total dissolved mercury. Methylmercury concentrations also were measured in samples collected from 45 selected sites. Total dissolved mercury concentrations were greatest in features from Washburn Hot Springs and West Nymph Creek Thermal Area. Methylmercury concentrations were greatest in samples from Frying Pan Spring and Sulphur Caldron and these are some of the highest concentrations known to occur naturally. Scientists found that mercury evasion appears to increase with increasing temperatures. To find out more, attend the poster session, W-90: Mercury Geochemistry in Yellowstone National Park (S-EB-4: Biogeochemical Controls on Mercury in Geothermal Systems) on Wednesday, August 9, during 10:00 a.m. - 1:00 p.m. Presenter: Kirk Nordstrom (dkn@xxxxxxxx).
Thursday, Aug. 10
Something Fishy in our Nation's Streams: The USGS examined mercury occurrence in water, streambed sediment, and fish from approximately 300 stream sites across the United States during 1998-2005. Stream water and streambed sediment were analyzed for total mercury, methylmercury, and characteristics thought to affect conversion of inorganic mercury to methylmercury, the most toxic form. Skin-off fish fillets of largemouth bass or other predator fish were analyzed for total mercury. The highest concentrations of total mercury in fish among all sampled sites occurred in western U.S. mining-affected sites and in eastern U.S. blackwater coastal-plain streams. Several blackwater coastal-plain streams had methylmercury concentrations that were similar to those of mining-affected sites despite total mercury concentrations that were much lower. This difference in the ratios of methylmercury to total mercury shows the importance of methylation as a controlling factor in the bioaccumulation of mercury in fish. To find out more, attend the platform session, S-1259: Mercury in Stream Water, Sediment, and Fish: Results from a National Survey (Topic: Environmental Monitoring and Assessment) on Thursday, August 10, at 4:00 p.m. in Ballroom C. Presenter: Barb Scudder (bscudder@xxxxxxxx).
Friday, Aug. 11
Reducing Mercury in Mines: Remediation of historic mercury mines has been completed at six of the 51 major California mine sites. Remediation at these sites is designed to reduce the levels of mercury in fish and in downstream aquatic environments that affect wildlife and human health. By studying these mine sites, USGS determined remediation methods that best mitigate release of mercury from mine sites and indicators that are useful in assessing conditions in which mercury can become an issue to fish or humans. To find out more, attend the platform session, S-814: Remediation of Historic Mercury Mine Sites in the California Coast Range on Friday, August 11, at 8:00 a.m. in Ballroom D. Presenter: James Rytuba (jrytuba@xxxxxxxx).
