This is really bad. NASA has published an image of the pollution haze taking all over the North China Plain. Yes, it's so bad that you can see it taking over thousands of square miles from space.
Cyclists travelling the car-filled streets of a city have one more hazard to worry about - black carbon from air pollution.
A British study has concluded that people who ride their bikes to work may be inhaling 2.3 times more black carbon than those who walk. And you thought riding your bike was healthier.
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