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Name: Brian
Status: other
Grade: other
Location: MD
Date: August 2008

What specifically causes an aluminum pot to turn black when boiling water? Is the water safe to drink?

Without a chemical analysis, I am not sure one can reliably predict what the black substance is. The reason is that while we refer to "aluminum" pots and pans the metal is alloyed with other metals for a particular application. There are dozens of aluminum alloys used in various commercial applications. One seldom sees "pure" aluminum except in chemical reagents. If toxicity were a major problem, I suspect its toxicity would have been identified by now, but I do not have any data on that point.

Vince Calder

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