Pittsburgh's air, and the other 10 chokiest cities

I thought Pittsburgh was pretty much fully recovered from its stint at the top of the pollution chain, but this article--which seems to be concerned less with statistics than with selecting a wide variety of cities--puts me hometown on a short list of the world's most polluted cities. Even if in actuality it's not in the top 10, it makes sense to me that Pittsburgh'd be at least woth an honorable mention. It has a rapidly expanding suburban sprawl filled with folks who love SUVs and Hummers, and, aside from its coaly steely history, it catches a lot of the industrial farts from Ohio. Still, despite the city being recently labeled America's most polluted city, I don't think the number of respritory problems compare to some of the other places on the list, like in Russia or China or Peru.