A new study in London found that bicycle commuters had 2.3 times as much black carbon in their lungs as those who get to work on foot. What does that mean? Well, cyclists breathe harder so they get all that nasty smog up in their lungs twice as much so they're all going to die like a bunch of West Virginia coal miners hawking up soot loogies. And here you thought you were being healthy and "green" pedaling around town. Does this mean I'm going to have to give up riding my bike to work, because I finally found a really cute helmet and I want to show it off?