Scientists From Canada, the US and Mexico Provide Guidance To Tackle Smog In North America

OTTAWA, April 1, 2003 ? Forty-two air quality scientists from Canada, the U.S. and Mexico have completed a three-year review of the current state of knowledge on airborne particles, a major component of smog in North America.
http://www.ec.gc.ca/press/2003/030401_n_e.htm