News tagged with coal

Related topics: carbon dioxide , fossil fuels

Herbal shisha a potential health hazard, study says

(Medical Xpress)—Just because something is marketed as herbal doesn't make it healthy—especially when it comes to smoking shisha, which can contain toxic metals, tar and other carcinogenic compounds sometimes ...

Nov 11, 2013
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'Black lung is back' researcher says

The dangers of coal mining enter the spotlight periodically when disasters strike, but one West Virginia University researcher argues that coal mine dust exposure, which has caused an increase in the prevalence and severity ...

May 17, 2013
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More Americans seeking dental treatment at the ER

(AP) -- More Americans are turning to the emergency room for routine dental problems - a choice that often costs 10 times more than preventive care and offers far fewer treatment options than a dentist's office, according ...

Feb 28, 2012
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Talk of treaty ban on mercury concerns scientists

(AP) -- Scientists are warning officials negotiating a global treaty on mercury that banning the deadly chemical completely would be dangerous for public health because of the chemical's use in vaccines.

Oct 21, 2011
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Alzheimer's protein kills nerve cells in nose

A protein linked to Alzheimer's disease kills nerve cells that detect odors, according to an animal study in the September 28 issue of The Journal of Neuroscience. The findings shed light on why people with Alzheimer's diseas ...

Sep 27, 2011
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Coal

Coal is a readily combustible black or brownish-black sedimentary rock normally occurring in rock strata in layers or veins called coal beds. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. It is composed primarily of carbon along with variable quantities of other elements, chiefly sulfur, hydrogen, oxygen and nitrogen.

Coal was formed from layer upon layer of annual plant remains accumulating slowly that were protected from biodegradation by usually acidic covering waters that gave a natural antiseptic effect combating microorganisms and then later mud deposits protecting against oxidization in the widespread shallow seas — mainly during the Carboniferous period — thus trapping atmospheric carbon in the ground in immense peat bogs that eventually were covered over and deeply buried by sediments under which they metamorphosed into coal. In this manner, over time, the chemical and physical properties of the plant remains (believed to mainly have been fern-like species antedating more modern plant and tree species) were changed by geological action to create a solid material.

Coal, a fossil fuel, is the largest source of energy for the generation of electricity worldwide, as well as one of the largest worldwide anthropogenic sources of carbon dioxide emissions. Gross carbon dioxide emissions from coal usage are slightly more than those from petroleum and about double the amount from natural gas. Coal is extracted from the ground by mining, either underground or in open pits.

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