There’s an interesting photo gallery at Popsci.com giving a brief overview of the 10 dirtiest cities on earth. While there are some no-brainers like Mexico City and Linfen, China, there are some surprise candidates too, like Milan and Pittsburgh, PA too.

I wonder if Peterborough, ON would make the top 10 list for Canada. Apparently our the air quality in my hometown is regularly worse than in Toronto, and I know for a fact that Little Lake, which sits in the heart of Peterborough, is at least one if not two orders of magnitude more PCB-contaminated than Lake Ontario.