AN ENVIRONMENTAL GEOCHEMISTRY APPROACH TO EXPOSURE ASSESSMENT RESULTING FROM A CHILDHOOD CANCER CLUSTER OCCURRENCE

There has been an unusually high incidence rate of childhood cancer in Hillcrest, NY; and citizens are concerned about present day and past exposure to pollutants within this suburban community. An exposure assessment from a geochemical perspective was used to document transport and deposition of pollutants in Hillcrest by 1) analysis of metal concentrations in surface water runoff, 2) determining historical variation in anthropogenic metal fluxes though use of sediment cores, and 3) measuring vapor phase Hg concentrations to model behavior of gaseous air pollutants. A large warehouse complex in Hillcrest that contributed runoff to a storm water retention pond was the primary sample collection site. Flow paced samples were collected from runoff exiting from the warehouse complex. Sediment was collected from the retention pond as well as from reservoir sediments from other locations in Broome County. Metal concentrations and decay products of 210Pb and 137Cs were measured to determine the timing of source specific differences in the distribution of pollutants in the sediment cores. Sedimentation rate normalized trace metal concentrations of Zn, Pb, Ni, Cu, Cr, Cd and As were elevated in the retention pond sediments when compared to sediment from other locations. In part, this finding resulted from impervious surface area of the warehouse roofs amplifying the signal of dry and wet deposition of pollutants from the atmosphere. Temporal changes in Pb deposition in sediment from the retention pond mimic consumption records of leaded gasoline. Superimposed over this regional signature of Pb deposition from the atmosphere are co-varying Zn, Ni, Cu, Cr and Cd concentrations; a suite of metals commonly used in metal plating processes by local industries. Fluctuations in vapor phase mercury concentrations resulted from topography enhanced variation in local meteorological conditions. In conclusion, exposure to elevated concentrations of metals in Hillcrest resulted from topography driven atmospheric transport and deposition of pollutants from local and regional anthropogenic sources.