Well it's not really unknown, but Boston's beloved Southeast Expressway has been ranked the seventh most polluting Interstate highway in the U.S.
A survey done by the folk at GPS provider TomTom shows seven of the ten dirtiest Interstates are in California. The others, besides the Expressway, are I-95 South in Virginia (understandable as an extension of the Beltway (hey, who puts a drawbridge on an Interstate (yep, it's there!))) and I-95 in Connecticut (tell me about it!).
And why didn't the mess in the Atlanta area and the Long Island Expressway make the list?
Learn more about our dirtiest roads and see which secondary arteries are the worst.
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