HR: 0800h
AN: B51D-0251    [Abstracts]
TI: Spatial Patterns of Airborne Exposures of Tungsten and Cobalt in Fallon, Nevada, From Lichens and Surface Sediments
AU: * Sheppard, P R
EM: sheppard@ltrr.arizona.edu
AF: Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ 85721 United States
AU: Speakman, R J
B51D-0251 AF: Research Reactor Center, University of Missouri, Columbia, MO 65211 United States
AU: Ridenour, G
B51D-0251 AF: General Practice, 1055 S. Taylor Street, Fallon, NV 89406 United States
AU: Glascock, M D
B51D-0251 AF: Research Reactor Center, University of Missouri, Columbia, MO 65211 United States
AU: Farris, C
B51D-0251 AF: Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ 85721 United States
AU: Witten, M L
B51D-0251 AF: Department of Pediatrics, University of Arizona, Tucson, AZ 85721 United States
AB: This paper describes spatial patterns of airborne exposures of heavy metals in Fallon, Nevada, where a cluster of childhood leukemia has been on-going since 1997. Lichen chemistry, the measurement and interpretation of element concentrations in lichens, and surface sediment chemistry were used. Lichens were collected from within as well as from well outside of Fallon. Surface sediments were collected in a gridded spatial pattern, also within and outside of Fallon. Both the lichen and the surface sediment samples were measured chemically for a large suite of metals and other elements. Lichens indicate that Fallon itself has a high dual airborne exposure of tungsten and cobalt relative to sites well away from the town. Surface sediments samples also show high peaks of tungsten and cobalt within Fallon with nothing more than background contents away from the town. The tungsten and cobalt peaks coincide spatially with one another, with the highest values located right at a "hard-metal" facility that processes these metals. This present research confirms earlier research on total suspended particulates showing that Fallon is distinct in Nevada for its high dual exposure of airborne tungsten and cobalt and that the source of these two metals can be pinpointed to the hard-metal industry that exists just north of Highway 50 and west of Highway 95. While it is still not possible to conclude that high airborne exposure of tungsten and/or cobalt causes childhood leukemia, it can now be concluded beyond reasonable doubt that Fallon is unique environmentally due to its high airborne concentrations of tungsten and cobalt. Given that Fallon's cluster of childhood leukemia is the "most convincing cluster ever reported," it stands to reason that additional biomedical research should directly test the leukogenecity of combined airborne exposures of tungsten and cobalt.
DE: 0461 Metals
SC: Biogeosciences [B]
MN: Fall Meeting 2005