Those combine to create a total risk of 336,000 in 1 million (based on the number of actual cancer cases), with the bulk of the risk widely attributed to lifestyle factors such as tobacco use, diet, lack of exercise, certain types of infections, and radiation.<a href=http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.119-a254#r3><sup>3</sup></a> For addi