Radon and Lung Cancer of Ohio A Geospatial Analysis Douglas Schoewe
Purpose of Project Analyze and Statistically calculate the spatial relationship between indoor radon levels and rates of lung cancer. Medical research attributes approximately 12 percent of lung cancer cases to radon 4. Geology research indicates indoor radon levels are related to the types of geological formation under which a home was built. No spatial correlation has yet been done to examine whether there is a definitive spatial relationship between the location of naturally occurring radon levels and the incidence of lung cancer of Ohio. [1] American Association of Lung Association, Fact Sheet 2006 lung cancer USA
Hypothesis The author believes that because 12 percent of all lung cancer cases are radon related there will be an observable spatial correlation between lung cancer and indoor radon levels that can be statistically calculated, and illustrated using Arc GIS and SPSS software.
Scope of Project Indoor Radon levels and Lung Cancer Data is standardized by the zip codes of Ohio Owing to previous research published on the geology of uranium across Ohio, this study examines areas lying within what is known as the “The Ohio Shale” formation and the Ohio glacier till region known to have above average amounts of uranium in the soil and bedrock.
Scope of Project
Background and Significance Lung cancer is the leading cancer killer of both men in women in the United States. It is estimated that in the United States for the year 2007, 213,380 new lung cancer cases will be reported along with 160,390 lung cancer deaths. Radon is the second leading cause of lung cancer killing between 15,000 and 22,000 people each year. 12 percent of all lung cancer deaths are linked to radon in the United States. In Ohio alone, there are about 7,700 new lung cancer cases each year. Radon is suspected of causing at least 900 of them. American Association of Lung Association, Fact Sheet 2006 lung cancer USA
About Radon Radon is a radioactive gas. It is colorless, odorless, tasteless, and chemically inert. Unless one tests for it, there is no way of telling how much is present. Radon is formed by the natural radioactive decay of uranium in rock, soil, and water. Radon has a half-life of about 3.5 days—half of a given quantity of it breaks down every 3.5 days. When radon undergoes radioactive decay, it emits ionizing radiation in the form of alpha particles. Radon gas also produces short-lived decay products, often called progeny or daughters, some of which are also radioactive. The progeny are not gases and can attach to dust and other particles. These radioactive particles get trapped in your lungs when you breathe. As they break down further, these particles release small bursts of energy which can damage lung tissue and lead to lung cancer over the course of a lifetime.
Radon Sources Geologic bedrock formation known as "Ohio Shale" enriched with uranium in amounts commonly between 10 and 40 ppm (ancient sea) Sediment (called "till") deposited by glaciers during the last Ice Age which ended in Ohio about 14,000 years ago 7
Radon Risks
Radon Data The indoor radon data was collected by participating Ohio residents whom tested their homes for radon. University of Toledo website. By zip code standardized by the GM (geometrical mean)
Lung Cancer Data The lung cancer data was provided for by The Ohio Cancer Incidence Surveillance System (OCISS). The data contains the percentages of lung cancer cases for years between 1996 and March 2007 by zip code
Other Data Digital Elevation Model of Ohio-USGS Zip code polygons- ESRI Bed Rock Data-USGS Radiometric Map Urban Polygons- ESRI
Data Acquisition All tables compiled, edited to Arc View compatibility, and projected NAD83StateplaneSouthwestern Ohio
Data Acquisition
Methods of Analysis Interpolation (Kriging) Clustering (Moran’s I autocorrelation, Getis-Ord, local clustering) Pearson’s Bivariate Linear Regression Query Analysis Terrain Observation Programs Used: Arc Info Statistical Tools and Spatial Analysis, Arc Scene, SPSS Statistical Software
Moran’s I Clustering
Interpolation (Kriging) Lung Cancer Indoor Radon
Getis- Ord Local Clustering Lung Cancer Indoor Radon
Pearson’s Bivariate
Linear Regression
Geological Analysis
Query Analysis
Terrain Observation Indoor Radon Lung Cancer
Indoor Radon Interpolation
Lung Cancer Interpolation
Results Found that there is a –1.5 bivariate correlation meaning a weak negative relationship (where there are high lung cancer percentages there are low indoor radon levels and visa versa) Found that areas along the Ohio Glacier Boundary have high levels of indoor radon Found that urban areas have high lung cancer and low indoor radon levels. (except Columbus, along the glacier boundary) Found that areas with undulated terrain have high indoor radon levels while level terrain have high lung cancer percentages. Disproved hypothesis- high indoor radon level areas do not equate to high lung cancer percentages! 12% of Radon Related Lung Cancer cases is not Spatially Observable.