This study may be of interest to you and your networks: http://www.sciencedaily.com/releases/2013/03/130307124427.htm Eloisa Raynault | American Public Health Association | 800 I Street NW, Washington DC 20001 | Transportation, Health and Equity Program Manager | o: 202-777-2487 | http://apha.org/transportation <http://apha.org/transportation> Please consider the environment before printing this e-mail.