Coal
Coal naturally contains high amounts of mercury. When coal is burned in coal power plants to produce electricity, it creates two sources of mercury exposure:
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mercury emissions into the atmosphere
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mercury in coal-combustible by-products (CCBs) such as fly ash
Recent research has implicated air-borne mercury as a contributing factor to autism. A 2008 Texas study found a significant increase in risk of autism diagnosis related to proximity to coal plants or other industrial mercury emitters (see Proximity to Point Sources of Environmental Mercury Release as a Predictor of Autism Prevalence). A 2006 San Francisco study found an association between autism and the amount of mercury in the air. See the SafeMinds Environmental Autism and Mercury flyer for more details.
“Clean Coal” will never be clean. Existing technologies can reduce airborne mercury emissions up to 90%. However, these technologies will not eliminate mercury air pollution or the concentrated mercury present in Coal-Combustion By-Products (CCBs) produced by coal-fired power plants. Long-term solutions are needed to shift energy production away from coal-fired power plants to cleaner non-mercury polluting technologies, like solar and wind technology. SafeMinds has written a policy statement for a mercury-free energy policy (download here). The policy statement includes SafeMinds views on coal, natural gas, and mercury-containing lightbulbs.
There is currently more regulatory focus on reducing mercury emissions. Whereas it is crucial to reduce mercury emissions with the best-available technology, technology does not provide a means to remove 100% of the mercury from emissions. Further, there is a concern that the technology used to reduce mercury emissions may result in an increased amount of mercury in Coal Combusion By-products (CCB’s, a.k.a. CCW “Coal Combustion Waste). And as the recent coal-ash spill in Tennessee demonstrated, CCB’s are a large and lightly-regulated source of exposure to mercury and other toxic chemicals.
CCB’s consist of fly-ash and other components that remain after coal is burned. CCB’s contain high levels of mercury, arsenic, lead, and other toxins. Some fly-ash is used as a component in products such as cement, gypsum board (drywall), and asphault, and eventually finds its way into trash dumps after the life cycle of those products are finished. Large quantities of fly-ash must be stored in coal-ash dumps. These coal-ash dumps generate mercury exposure via off-gassing (vapor), waterway contamination (leakage into the water table), and conversion of elemental mercury into methylmercury by bacteria in waste ponds and CCB soils. Additionally, there is the on-going risk of massive waterway contamination due to dam breaks such as in Tennessee in December 2008.
Details on Coal Combustion By-products:
Coal Ash Spills Too Dangerous To Reveal To Public, Says DHS (VIDEO) – 6/12/09
Coal’s other mess: As the air around power plants clears, another problem worsens – 11/26/07
Coal Ash: The Hidden Story
How Industry and the EPA Failed To Stop a Growing Environmental Disaster – 2/19/09
Source Watch online encyclopedia, “Coal Waste” article
One of coal’s big messes is transformed into building blocks – 7/16/08
Coal Ash: A National Problem Needs a National Solution – 2009
Sierra Club and Earth Justice
Release of Mercury Vapor from Coal Combustion Ash – 2001
David J. Hassett, Loreal V. Heebink,
University of North Dakota Energy and Environmental Research Center
Microbial Release of Mercury from Coal Combustion By-products (CCBs)
David J. Hassett, Loreal V. Heebink,
John R. Gallagher, and Debra F. Pflughoeft-Hassett
University of North Dakota Energy and Environmental Research Center
Is Your Baby Crawling On Carpet Made Of Coal Ash?
Deirdre Imus (SafeMinds Board Member), Huffington Post, 11/23/09
Details on Mercury in Coal:
Fractions and Leaching Characteristics of Mercury in Coal
Chun-Gang Yuan, Qing-Peng Li, Ya-Na Feng, Ai-Ling Chang
School of Environmental Science and Engineering
North China Electric Power University