References:
1.Wogan GN, Hecht SS, Felton JS, Conney AH, Loeb LA. Environmental and chemical carcinogenesis. Semin Cancer Biol. 2004 Dec;14(6):473-86. http://www.ncbi.nlm.nih.gov/pubmed/15489140
2.Alfano CM, Klesges RC, Murray DM, Bowen DJ, McTiernan A, Vander Weg MW, Robinson LA, Cartmel B, Thornquist MD, Barnett M, Goodman GE, Omenn GS. Physical activity in relation to all-site and lung cancer incidence and mortality in current and former smokers. Cancer Epidemiol Biomarkers Prev. 2004;13(12):2233-2241. http://www.ncbi.nlm.nih.gov/pubmed/15598785
3.Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids : a report of the Panel on Dietary Antioxidants and Related Compounds, Subcommittees on Upper Reference Levels of Nutrients and Interpretation and Uses of Dietary Reference Intakes, and the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, Institute of Medicine. Institute of Medicine (US) Panel on Dietary Antioxidants and Related Compounds. Washington, D.C. : National Academy Press, c2000. http://www.ncbi.nlm.nih.gov/nlmcatalog/100938980