How does does oil pollute the earth?

Answer 1

Oil comes from underground. When it is extracted, it needs to be stored/contained in a crude state or refined state. Two sources of pollution come to mind -- (a) oil spill and (b) incomplete combustion/green house effects when burned.

Unintended oil spills result in the slick/gooey liquid covering the ground during handling or the water when the oil is transported over water. Oil seeping into soil will harm plants by choking off nutrients, and human when it contaminates the water underground. Oil spills in water will harm sea lives by choking off oxygen and digestive systems Birds who are in contact with the spilled oil can be harmed the same way.

Incomplete combustion of oil causes toxic fumes which contaminate the air that we breathe. Even when oil is burned efficiently, CO2 emission can still cause green house effects -- raising the earth's surface temperature (global warming).

Oil spills can be contained/localized (minimizing harmful effects) or neutralized (use of absorbent material or bacteria.) However, still, it takes resources (time and energy) to clean up. The environment is still not quite the same afterward, like drying spilled coffee on a piece of white paper -- the piece is still wrinkled and brownish after cleaning.

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