Opportunities in Chemistry Today and Tomorrow (1987) / Chapter Skim
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II. Environmental Quality Through Chemistry
II. Environmental Quality Through Chemistry
Pages 5-20
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From page 5... ...
Occasional industrial accidents, like those at Bhopal, India and Seveso, Italy, remind us that large-scale production of needed consumer products may require handling of large amounts of potentially dangerous feedstock substances. The tragic Bhopa]
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From page 6... ...
If the worId's mortality rate due to malaria is not to be reduced with DDT because of its environmental persistence, what substances can be synthesized that are equally effective in saving lives but are spontaneously decomposed? If we must use lower-grade energy sources to satisfy our energy needs, what catalysts and new processes can be developed to avoid making worse the existing problems of acid rain and carcinogen release from coal-fired power plants?
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From page 7... ...
Scientists, including chemists, must carry responsibility for providing the public, the media, and the government with a factual picture expressed in language free of technical jargon. That picture must establish the scientific setting for a given decision and indicate the options that lie before us.
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From page 8... ...
Conclusions regarding the sources, movements, and fates of pollutants depend upon adequate environmental measurements, whether the issue is acid rain, global climate change, ozone layer destruction, or toxic waste disposal. Enormously costly decisions about how to protect the quality of our air, water, and land resources are sometimes based on environmental information that is dangerously inadequate and inaccurate.
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From page 9... ...
Arsenic in some forms can move rapidly through natural underground water supplies, while other forms are held tightly, adsorbed on rock or soil surfaces. Of the 22 distinct structural arrangements of tetrachiorodioxin, one of them is a thousand times more toxic to test animals than the second most toxic form.
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From page 10... ...
To understand how easily the ozone layer might be disturbed, it is useful to recognize that ozone is actually only a trace constituent of the stratosphere; at its maximum concentration ozone makes up only a few parts per million of the air molecules. If the ozone layer were concentrated into a thin shell of pure ozone gas surrounding the Earth at atmospheric pressure, it would measure only about 3 millimeters (1/8 inch)
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From page 11... ...
Of course, oxides of nitrogen directly introduced into the stratosphere are expected to destroy ozone as well, and this was the basis of the first perceived threat to the ozone layer large fleets of supersonic aircraft flying in the stratosphere and depositing oxides of nitrogen through their engine exhausts. Nuclear explosions also produce very large quantities of oxides of nitrogen, which are carried into the stratosphere by the buoyancy of the hot fireballs; a significant depletion of the ozone layer in the event of a major nuclear war was forecast in a 1975 study by the National Academy of Sciences, although this environmental effect of nuclear war may be insignificant in comparison with the recently suggested potential of a `'nuclear winter." Both effects underscore the delicacy of the atmo'sphere and its sensitivity to chemical transformations.
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From page 12... ...
As the instrument travels through the stratosphere, it measures concentrations of several important trace chemical species and relays the information to a ground station. Very recently, the first successful reel-down experiment was performed in which the instrument package was lowered 10 to 15 km from a stationary balloon platform and reeled back up
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From page 13... ...
The greatest damage is done to lakes that are poorly buffered. When natural alkaline buffers are present, the acidic compounds in acid rain, largely sulfunc acid, nitric acid, and smaller amounts of organic acids, are neutralized.
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From page 14... ...
Catalysts that reduce oxides of nitrogen emissions from both stationary and mobile sources offer yet another example of the role that chemistry can play in improving air quality. The various strategies for reducing acid rain involve possible investments of billions of dollars annually.
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From page 15... ...
Atmospheric and environmental chemistry are central to a clearer and more healthful environment. Development of reliable methods of measurement of trace species in air, kinetics of important atmospheric reactions, and the discovery of new, more effective chemical processes for reducing pollutant emissions are goals that must receive a national commitment for the coming decade.
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From page 16... ...
Unlike local pollutants, the global pollutant problems are perplexing because they require action on a global scale and the citizens of different countries view their priorities differently. Whether individual countries have emphasized fossil fuel versus nuclear fuel in the past has been based primarily on economic factors such as whether that nation had abundant coal reserves.
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From page 17... ...
. Groundwater quality can also be improved by developing improved methods for treating wastewaters, including industrial wastewaters that contain especially stable contaminants.
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From page 18... ...
. This need for long-range predictability implies that we should be looking at other means of dealing with radioactive waste besides underground storage, means that will permit easier access to and monitoring of waste deposits.
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From page 19... ...
ACS Information Pamphlets "Acid Rain," 8 pages, December 1985. "Chemical Risk: A Primer," 12 pages, December 1984.
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