`Using chlorine'

Regarding the Associated Press story ``Chlorine: Safe Chemical or Toxic Threat?'' Dec. 15: It reports a 1992 proposal for a phaseout of the industrial use of chlorine in the Great Lakes region. Bonnie Rice of Greenpeace's Chlorine Free Campaign states, ``Using chlorine is going to end life as we know it....''

How do we define the term ``using chlorine''? To clarify the Greenpeace position it would be useful to inquire whether Ms. Rice is referring to free, bound, molecular, free-radical, ionic, or covalent chlorine, the properties of which are vastly different.

Does Rice's unqualified statement relate to the use of chlorine in the purification of drinking water for more than a century? Volcanoes have been puffing out poisonous chlorine gas since before the Pleistocene Epoch.

We need a workable definition of ``using chlorine,'' including an indication of what kind and how much, and less of the currently fashionable knee-jerk reaction to the ``toxic-chemical'' syndrome. Robert B. Henn, Ambler, Pa.

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