Small caveat...
The article he linked to was a valid one. Note that the article doesn't blame the Antarctic ozone hole on rocket exhaust either (which is silly), but it's fair to be concerned about any possible pollutant that is injected into the high atmosphere where it isn't subject to the influences that clean out the lower layers fairly well.
I looked at this a bit myself once when I was pushing a liquid-fuel alternative to solid boosters (liquids are still a better idea. See? There's always an axe to be ground.) There are lots of papers on the subject.