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Show Other epidemiological and scientific studies have shown an overall increase in the cancer burden in populations exposed to dioxin (Bertazzi, et al., 2001, Kogevinas, M., 2001, Smith, A. and Lopipero, P., 2001, Steenland, et al., 2001). To look at this all re-portable cancers were combined and the RRs were calculated. None of the areas examined in this study, Davis County, North Davis County, nor South Davis County showed an elevation in the RR for all cancers combined (table 1). Obtaining meteorological data from HAFB lends strength to the study because it is located one mile west of the plant. In that WES' stack emissions of dioxin were the alleged exposure, the prevailing winds would determine areas of high and low exposure to dioxin. When the cases were plotted by address and the wind plumes were overlaid there was no apparent correlation between where the wind blew most often and cancer cases. Another benefit of this study is the demonstration of techniques which can be used for future "cancer cluster" investigations. One of the key elements is discussing the utility of observed to O/E ratios in contrast to RRs. O/E ratios can be used to obtain a simple evaluation of amount of disease in a population compared to what is expected. Rate Ratios on the other hand are well suited for both comparisons across populations and time as well as adjusting. Conclusion Looking at the cancer burden around the WES plant, in Layton, and by subdivisions of Davis County shows no excess cancer burden. Davis County experiences cancer close to the cancer rates of the state of Utah. The belief that Davis County has a higher cancer burden than would be expected is not supported. While cursory O/E ratios can help direct attention to potentially elevated events, they are not useful in drawing conclusions, because they are not comparable across different populations or overtime. An increase in brain cancer following exposure to dioxin was not found in the present scientific data or by the examination of the cancers possibly associated with dioxin exposure. While the health effects of dioxin should be continuously examined, it has not been shown to be associated with brain cancer in Davis County in this study. References 1. Agency for Toxic Substances and Disease Registry (1992). Congressional Testimony Public Health Implications ofDioxins. [Online] http:// www.atsdr.cdc.gov/test-06-10-92.html/. Retrieved 5/14/01. 2. Becher, H., Flesch-Janys, D., Kauppinen, T., et al. (1996). Cancer mortality in German male workers exposed to phenoxy herbicides and dioxins. Cancer Causes Control, 7:312-321. 3. Balesracci Jr.. D., & Barlow, J. (1996). Quality Improvement. Practical Applications for Medical Group Practice, Englewood, CO: Center for Research in Ambulatory Health Care Administration. 4. Bertazzi, P.A., Consonni, D., Bachetti. S., Rubagotti, M., Baccarelli. A,, Zocchetti, C, Pesatori, A.C. (2001a). Health Effects of Dioxin Exposure: A 20-Year Mortality Study. AmJofEpi, 153(11): 1031-1044. 5. National Toxicology Program. NIEHS PR #01-04 (January 19. 2001). TCDD - Dioxin is Listed as "Known Human Carcinogen" in Federal Government's Ninth Report On Carcinogens. [Online] http://www.mehs. nih.gov/oc/news/dioxadd.htm/. Retrieved 3/25/02 6. National Weather Service. Western Region Headquarters. [Online] http://www.wrh.noaa.gov/Saltlake/climate/ismcs.hif.html/. Retrieved 5/25/01 7. Kogevinas, M., Kauppinen. T., Winkelmann, R., Becher, H., Bertazzi, P.A., Bueno-de-Mesquita. H.B., Coggon, D., Green. L., Johnson, E.. Littorin. M., et al. (1995). Soft tissue sarcoma and non-Hodgkin's lym-phoma in workers exposed to chlorophenoxy herbicides, chlorophenols and dioxins: two nested case-control studies. Epidemiology, 6: 396-402. 8. Kogevinas, M. (2001 May-June). Human health effects of dioxins: cancer, reproductive and endocrine system effects. Hum. Repord. Update. 3:331-339. 9. Pagano, M., & Gauvreau. K. (2000). Principles of Biostatistics, second edition. Pacific Grove CA: Duxbury. 10. Smith. A., Lopipero, P. (2001). Invited Commentary: How Do the Seveso Findings Affect Conclusions Concerning TCDD as a Human Carcinogen? Epidemiology, 153(11): 1045-1047. 11. Steenland, K.. Deddens, J., Piacitelli, L. (2001). Risk Assessment for 2,3,7,8-Tetrachlorodibenzo-/?-Dioxin (TCDD) base on an Epidemiological Study. Amer. J. ofEpi, 154(5): 451-458. 12. United States Census Bureau. American Fact Finder (2000). [Online] http://factfinder.census.gov/. Retrieved 6/20/01. 13. United States Environmental Protection Agency, Office of Research and Development, (2001a). [Online] http://www.epa.gov/ncea/dioxin/. htm. Retrieved 5/15/01. 14. United States Census Bureau. SEER (1998). [Online] http://seer. cancer.gov/Publications/CSR 1973_1998/allsites.pdf/. Retrieved 2/1/02 15. Viel. J.F., Arveux. P., Baverei, J., Cahn, J.Y. (2000). Soft-Tissue Sarcoma and Non-Hodgkin"s Lymphoma Clusters around a Municipal Solid Waste Incinerator with High Dioxin Emission Levels. Am J ofEpi, 152(1): 13-19. About the Authors Jeremy J. Biggs is a MSPH graduate from the University of Utah, Department of Family and Preventive Medicine, Public Health Programs. Aaron M. Wendelboe is a MSPH graduate from the University of Utah, Department of Family and Preventive Medicine, Public Health Programs. Dr. George L. White Jr. is the director of the Public Health Programs at the University of Utah, Department of Family and Preventive Medicine. He is also a professor in the Public Health Programs. Lewis Garrett is the County Health Officer for the Davis County Health Department. Dr. Joseph L. Lyon is a professor of Epidemiology at the University of Utah, Department of Family and Preventive Medicine, Public Health Programs. For questions or comments please contact Dr. Lyon, jlyon@dfpm.utah.edu, 801-587-3350. 46 Utah's Health: An Annual Review Volume VIII |