Water
pollution is a major global problem which requires ongoing evaluation and
revision of water resource policy at all levels. It has been suggested that
water pollution is the leading worldwide cause of deaths and diseases, and that
it accounts for the deaths of more than 14,000 people daily. An estimated 580
people in India die of water pollution related illness every day. About 90
percent of the water in the cities of China is polluted. As of 2007, half a
billion Chinese had no access to safe drinking water. In addition to the acute
problems of water pollution in developing countries, developed countries also
continue to struggle with pollution problems. For example, in the most recent
national report on water quality in the United States, 44 percent of assessed
stream miles, 64 percent of assessed lake acres, and 30 percent of assessed
bays and estuarine square miles were classified as polluted. The head of
China’s national development agency said in 2007 that one quarter the length of
China’s seven main rivers were so poisoned the water harmed the skin.
Water is typically referred to as
polluted when it is impaired by anthropogenic contaminants and either does not
support a human use, such as drinking water, or undergoes a marked shift in its
ability to support its constituent biotic communities, such as fish. Natural
phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause
major changes in water quality and the ecological status of water.
1. What is the leading worldwide cause
of deaths and diseases?
2. How many people die every day by
water pollution?
3. How many percent of the water in
the cities of China is polluted?
5. What phenomena cause major changes
in water quality and the ecological status of water?
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