Walking and cycling good for health even in cities with higher levels of air pollution | University of Cambridge
Reference Tainio et al. Can air pollution negate the health benefits of cycling and walking? Preventive Medicine; 5 May 2016; DOI: 10.1016/j.ypmed.2016.02.002 - See more at: http://www.cam.ac.uk/research/news/walking-and-cycling-good-for-health-even-in-cities-with-higher-levels-of-air-pollution#sthash.QIZhQfOL.dpuf