Proportions of human cancer deaths attributed to various factors Proportions of human cancer deaths attributed to various factors. (Reproduced with permission from [no authors listed] Harvard reports on cancer prevention: causes of human cancer. Center for Cancer Prevention Harvard School of Public Health. Cancer Causes and Control. 1996;7 (Suppl 1):S3–S4, 1996.) Source: Chemical Carcinogenesis, Casarett and Doull's Toxicology: The Basic Science of Poisons, 8e Citation: Klaassen CD. Casarett and Doull's Toxicology: The Basic Science of Poisons, 8e; 2012 Available at: http://accessbiomedicalscience.mhmedical.com/DownloadImage.aspx?image=/data/books/958/kla008_fig_08-01.png&sec=53486989&BookID=958&ChapterSecID=53483729&imagename= Accessed: October 31, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved