Answer:
The poisoning of the world's land, air, and water is the fastest-spreading disease of civilization. It is potentially one of history's greatest dangers to human life on earth. If present trends continue for the next several decades, our planet will become uninhabitable.
Overpopulation, pollution and energy consumption have created such planet-wide problems as massive deforestation, ozone depletion, acid rains and the global warming that is believed to be caused by the greenhouse effect. The seas are in danger. They are filled with poison: industrial and nuclear waste, chemical fertilizers and pesticides. The Mediterranean is already nearly dead; the North Sea is following. The Aral Sea is on the brink of extinction'. If nothing is done about it, one day nothing will be able to live in the seas.
Air poluttion is a very serious problem. In Cairo just breathing the air is life threatening - equivalent to smoking two packs of cigarettes a day. The same holds true for Mexico City. Industrial enterprises emit tons of harmful substances. These emissions have disastrous consequences for our planet. They are the main reason for the greenhouse effect and acid rains.
An even greater environmental threat is nuclear power stations. People are beginning to realise that environmental problems are not somebody else's. They join and support various international organizations and green parties.