Pollution

Coal can be quite a 'dirty' fuel.

When burnt, coal can release ozone, sulphur dioxide and particulate smoke (or ash). Some of these emissions can contribute to creating smog over our cities or even acid rain.

Coal also contains traces of elements that are poisonous, such as mercury and arsenic. Mercury in particular can stay suspended in the atmosphere long enough to circulate around the world.

Burning coal can even release low level radiation into the air. In fact, a coal-burning power plant can release more radiation than a nuclear power plant! (How Stuff Works )

Health researchers report that these pollutants can contribute to respiratory diseases, cancers and other health issues. The pollution released in the past has also contributed to a number of the environmental problems we face today.

In past centuries, pollutants from burning coal were released into the atmosphere with little understanding of the potential risks.

Today, countries are much more careful about how they regulate the amount of pollution that is released into the atmosphere. Scientists and engineers have worked to develop methods of using coal which reduce the pollution that may be released, or capture and filter the pollution.

Coal can also cause pollution simply by being mined. Coal dust released by the explosions and large mining efforts used to extract coal can be harmful to the health of animals and plants; and can also cover everything nearby with a layer of black coal dust.

Today, scientists have invented many ways to reduce the release of this dust. Roads, stockpiles and transport conveyors are sprayed with special materials that help control dust levels. Mining drills are fitted with dust collection devices and additional land surrounding the mine may be purchased to form a buffer zone between the mine and its neighbours.