Eero Suonio

Members Ahti Anttila, Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Liisankatu 21 B, 00170 Helsinki, Finland Ramesh V. Bhat, National Institute of Nutrition, Indian Council of Medical Research, Jamai-Osmania PO, Hyderabad-500 007 AP, India James A. Bond, Chemico-Biological Interactions, Toxcon, 5505 Frenchmans Creek, Durham, NC 27713, USA Susan J. Borghoff, CIIT Centers for Health Research, 6 Davis Drive, Box 12137, Research Triangle Park, NC 27709-2127, USA F. Xavier Bosch, Epidemiology Unit and Cancer Registry, Catalan Institute of Oncology, Av. Gran via s/n, Km. 2.7, 08907 L’Hospitalet del Llobregat, Spain Gary P. Carlson, School of Health Sciences, 1338 Civil Engineering Building, Purdue University, West Lafayette, IN 47907-1338, USA Marcel Castegnaro, Les Collanges, 07240 Saint-Jean-Chambre, France George Cruzan, ToxWorks, 1153 Roadstown Road, Bridgeton, NJ 08302-6640, USA Wentzel C.A. Gelderblom, Programme on Mycotoxins and Experimental Carcinogenesis, Medical Research Council (MRC), PO Box 19070, Tygerberg, South Africa 7505 Ulla Hass, Institute of Food Safety and Toxicology, Morkhoj Bygade 19, 2860 Soborg, Denmark Sara H. Henry, 5100 Paint Branch Parkway, College Park, MD 20740-3835, USA Ronald A. Herbert, Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences, PO Box 12233, Mail Drop B3-08, Research Triangle Park, NC 27709-2233, USA Marc Jackson, Integrated Laboratory Systems, Inc., PO Box 13501, Research Triangle Park, NC 27709, USA IARC WORKING GROUP ON THE EVALUATION OF CARCINOGENIC RISKS TO HUMANS: SOME TRADITIONAL HERBAL MEDICINES, SOME MYCOTOXINS, NAPHTHALENE AND STYRENE

BACKGROUND: After the Chernobyl nuclear power plant accident in April 1986, a large increase in the incidence of childhood thyroid cancer was reported in contaminated areas. Most of the radiation exposure to the thyroid was from iodine isotopes, especially 131I. We carried out a population-based case-control study of thyroid cancer in Belarus and the Russian Federation to evaluate the risk of thyroid cancer after exposure to radioactive iodine in childhood and to investigate environmental and host factors that may modify this risk. METHODS: We studied 276 case patients with thyroid cancer through 1998 and 1300 matched control subjects, all aged younger than 15 years at the time of the accident. Individual doses were estimated for each subject based on their whereabouts and dietary habits at the time of the accident and in following days, weeks, and years; their likely stable iodine status at the time of the accident was also evaluated. Data were analyzed by conditional logistic regression using several different models. All statistical tests were two-sided. RESULTS: A strong dose-response relationship was observed between radiation dose to the thyroid received in childhood and thyroid cancer risk (P<.001). For a dose of 1 Gy, the estimated odds ratio of thyroid cancer varied from 5.5 (95% confidence interval [CI] = 3.1 to 9.5) to 8.4 (95% CI = 4.1 to 17.3), depending on the risk model. A linear dose-response relationship was observed up to 1.5-2 Gy. The risk of radiation-related thyroid cancer was three times higher in iodine-deficient areas (relative risk [RR]= 3.2, 95% CI = 1.9 to 5.5) than elsewhere. Administration of potassium iodide as a dietary supplement reduced this risk of radiation-related thyroid cancer by a factor of 3 (RR = 0.34, 95% CI = 0.1 to 0.9, for consumption of potassium iodide versus no consumption). CONCLUSION: Exposure to (131)I in childhood is associated with an increased risk of thyroid cancer. Both iodine deficiency and iodine supplementation appear to modify this risk. These results have important public health implications: stable iodine supplementation in iodine-deficient populations may substantially reduce the risk of thyroid cancer related to radioactive iodines in case of exposure to radioactive iodines in childhood that may occur after radiation accidents or during medical diagnostic and therapeutic procedures.

This overview describes the principles of the 4th edition of the European Code against Cancer and provides an introduction to the 12 recommendations to reduce cancer risk. Among the 504.6 million inhabitants of the member states of the European Union (EU28), there are annually 2.64 million new cancer cases and 1.28 million deaths from cancer. It is estimated that this cancer burden could be reduced by up to one half if scientific knowledge on causes of cancer could be translated into successful prevention. The Code is a preventive tool aimed to reduce the cancer burden by informing people how to avoid or reduce carcinogenic exposures, adopt behaviours to reduce the cancer risk, or to participate in organised intervention programmes. The Code should also form a base to guide national health policies in cancer prevention. The 12 recommendations are: not smoking or using other tobacco products; avoiding second-hand smoke; being a healthy body weight; encouraging physical activity; having a healthy diet; limiting alcohol consumption, with not drinking alcohol being better for cancer prevention; avoiding too much exposure to ultraviolet radiation; avoiding cancer-causing agents at the workplace; reducing exposure to high levels of radon; encouraging breastfeeding; limiting the use of hormone replacement therapy; participating in organised vaccination programmes against hepatitis B for newborns and human papillomavirus for girls; and participating in organised screening programmes for bowel cancer, breast cancer, and cervical cancer.