GEOCHEMICAL STUDY OF URBAN ENVIRONMENTS WITH EXCESS DISEASE PREVALENCE: FALLON, NEVADA

A geochemical study has been done in Fallon, Nevada, which has experienced a cluster of childhood leukemia. Trace metal chemistry of airborne and surface outdoor dust was measured and described within Fallon (case town) as well as in other nearby similar towns and outlying desert areas (comparison towns). Multiple lines of evidence, including airborne dust filtered directly from air, deposited dust collected from ground surfaces, and lichens collected from native bedrock, indicate high levels of airborne tungsten and cobalt within Fallon relative to comparison towns and pristine desert. Morphological and chemical analyses of airborne tungsten particles of Fallon indicate that they are anthropogenic in origin, i.e., pure tungsten or tungsten carbide with traces of cobalt and other metals. Dendrochemical analysis of tree rings within Fallon indicates that environmental tungsten has increased in availability since the mid-1990s, at or about the time of onset of the cluster of childhood union. Although these findings do not directly link exposure to airborne tungsten and cobalt to childhood leukemia, they do suggest new lines of biomedical research to evaluate if such linkages exist. More generally, geochemistry of multiple lines of evidence can identify distinctive environmental qualities of towns, and those distinctions can then be investigated further in directed public health research.