[1] Univ British Columbia, Sch Environm Hlth, Vancouver, BC V6T 1Z3, Canada
[2] Univ British Columbia, Sch Human Kinet, Vancouver, BC V6T 1Z3, Canada
[3] British Columbia Ctr Dis Control, Vancouver, BC, Canada
[4] Swiss Trop & Publ Hlth Inst, Basel, Switzerland
[5] Univ Basel, Basel, Switzerland
[6] Int Agcy Res Canc, F-69372 Lyon, France
[7] Harvard Univ, Beth Israel Deaconess Med Ctr, Sch Med, Cardiovasc Epidemiol Res Unit, Boston, MA 02215 USA
[8] Univ British Columbia, Div Resp Med, Vancouver, BC V6T 1Z3, Canada
[9] St Pauls Hosp, Providence Heart & Lung Inst, Vancouver, BC V6Z 1Y6, Canada
[10] Simon Fraser Univ, Fac Hlth Sci, Burnaby, BC V5A 1S6, Canada
[11] Univ British Columbia, Dept Med, Vancouver, BC V6T 1Z3, Canada
[12] Hlth Canada, Healthy Environm & Consumer Safety Branch, Populat Studies Div, Ottawa, ON K1A 0L2, Canada
[13] Univ Ottawa, Dept Epidemiol & Community Med, Ottawa, ON, Canada
[14] Univ Montana, Ctr Environm Hlth Sci, Missoula, MT 59812 USA
[15] Univ Montreal, Dept Sante Environm & Sante Travail, Montreal, PQ, Canada
[16] Inst Natl Sante Publ Quebec, Montreal, PQ, Canada
[17] Univ Washington, Dept Environm & Occupat Hlth Sci, Seattle, WA 98195 USA
[18] Univ London, London Sch Hyg & Trop Med, London, England