established that exposure to tobacco causes death, disease and disability The Health Consequences of Involuntary Exposure to TobaccoSmoke: A Report of the Surgeon
'environmental' tobaccosmoke) causes lung cancer in humans. [...] Involuntary smoking (exposure to secondhand or 'environmental' tobaccosmoke) is carcinogenic
Disease Control and Prevention. Secondhand Smoke (页面存档备份,存于互联网档案馆) by BeTobaccoFree.gov Tobacco Facts - Why is Tobacco So Addictive?. Tobaccofacts.org. [2008-09-18]