Source: Canadian Architect, January 1985
These three local towers were...
While searching for information regarding Morton Thiokol and polysulfides that didn't involve deep scientific analysis of the chemical composition of the sealant used in these Toronto landmarks, we ran into an interesting tidbit from the current manufacturer: the sealant should have a "twenty-year service life under normal conditions."
Makes you want to watch your head while passing by any of these structures, doesn't it?

Elsewhere in the Ist-a-Verse
Oh, and here I was thinking the reason that First Canadian Place has been falling apart was because I cursed it after finding out that the old Toronto Star building was demolished to make room for it.
Oh well, whatever works I guess.
The name Morton Thiokol brings back memories of this:
http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disaster