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The Saga of Fume: On exerting yourself in traffic
Dear Umbra, I bus, bike, or walk to work 98 percent of the time. I was wondering, when I'm biking (or walking, for that matter), am I inhaling more pollutants than those around me who are emitting them from their gas-guzzlers? Your answer won't change my habits, since I'm not going to drive to work anytime soon -- I'm just wondering if I'm the one paying the price for my enviro-friendly commuting? Thanks for your help! Sara, Tucson, Ariz.