Sydney, Cape Breton has for several years gotten an iconic symbol for its industrial past. Whether or not it's bad for tourism, the infamous 'Human Health Hazard' signs that used to be put up all over North Sydney often came to mind when Sydney was mentioned. Around 2009 the signs were removed, likely sent off to a dump somewhere... and it is extremely difficult to find a clear photo of one:
This was an attempt to 'rescue' the sign by drawing it on Microsoft Paint. It's not the closest but it's okay.
Then there's the design I did for the back cover of my novel Smog City, which I drew on MS Paint and has the same 'Human Health Hazard' sign on the back: