HEALTH: Power plants major influence in regional mercury emissions (ACTION ALERT!)

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Power plants major influence in regional mercury emissions

By Yale University

Jul 22, 2006, 22:40

 

New Haven, Conn. -- The amount of mercury emitted into the atmosphere in

the Northeast fluctuates annually depending on activity in the electric

power industry, according to researchers at the Yale School of Forestry

& Environmental Studies.

 

Xuhui Lee, professor of meteorology, and Jeffrey Sigler, a recent Yale

Ph.D. and now a postdoctoral researcher at the University of New

Hampshire, co-authored the Yale study " Recent Trends in Anthropogenic

Mercury Emission in the Northeast United States. " They found that

between 2000 and 2002 the emission rate of mercury decreased by 50

percent, but between 2002 and 2004 the rate increased between 50 and 75

percent. During that five-year period, overall emissions declined by 20

percent.

 

The dramatic annual changes in mercury emissions, the study's authors

say, cannot be explained climatologically by air flow patterns that

would bring either clean or polluted air into the region.

 

Mild winters and a correspondent decrease in the need for regional power

plants to burn coal could partially explain the decline in mercury

emissions, according to the authors. The study, published this summer in

the Journal of Geophysical Research-Atmospheres, estimates that power

plants account for up to 40 percent of total emissions in New Jersey,

New York and Pennsylvania and in New England.

 

" The study highlights just how important power plants are in influencing

regional mercury emission, " said Sigler. " We should not forget other

source categories when formulating abatement policies, since they also

contribute significant amounts to the total emissions, " Lee added.

 

Mercury, which converts to highly toxic methyl mercury in ground water,

is found in fish and can cause neurological problems in developing

fetuses and dementia and organ failure in adults who eat fish in large

amounts and over long periods.

 

The Yale study was conducted at Great Mountain Forest in northwestern

Connecticut. The measurements were restricted to wintertime so data on

carbon dioxide that comes from the same combustion sources as mercury

would not be distorted by photosynthesis. The researchers used carbon

dioxide to trace mercury back to its sources with a unique method called

" tracer analysis. "

 

" To our knowledge, using the carbon dioxide to trace mercury over a long

time period hasn't been done before, " said the authors. " We started with

actual mercury that's in the atmosphere, worked back to sources that

emit it, then calculated the emission rate. "

 

The U.S. Environmental Protection Agency, which does not regulate

mercury emissions, determines the mercury emission rate by taking an

inventory of existing sources. " Although the EPA's approach is highly

useful, it requires accurate measurements of mercury emitted from the

smokestack per ton of fuel burned, " said Sigler. " These data are hard to

come by. Our top-down technique circumvents those rather cumbersome

problems and allows for much more timely estimates of mercury emission.

It's difficult to get annual changes in the emission rate with the

inventory approach. "

 

 

Contact: Janet Rettig Emanuel

janet.emanuel

203-432-2157

 

David DeFusco

david.defusco

203-436-4842

 

http://www.foodconsumer.org/777/8/Power_plants_major_influence_in_regional_mercu\

ry_emissions.shtml

 

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