14. Geographical Factors

Cancer rates vary significantly throughout the United States. In general, states with high rates are the industrial states. Analysis county by county reveals that a majority of the areas of high mortality from cancer are located in large cities. For example, the high mortality in Illinois reflects rates in the Chicago area.

It has long been known that densely-populated and industrialized areas have higher death rates from many causes than nearby rural areas. Urbanization and mortality have been associated for heart disease, cancer of the respiratory and digestive systems, and many other diseases. This excess health risk is related to lifestyle (urban dwellers use more tobacco), to occupation (working with industrial pollutants), to the environment of cities (air and water pollution), and to other factors.