There is a useful summary of the effects of secondhand smoke on non-smokers at:
http://thechart.blogs.cnn.com/2010/11/26/secondhand-smoke-kills-600000-worldwide-annually/.

For more on cigarette smoking and lung cancer, see:
“Molecular Clues to Preventing Tobacco-Related Lung Cancer,” http://www.nypcancerprevention.com/issue/7/pro/feature/molecular-clues-to-preven.shtml.