Human Exposure to Metals, Pesticides, VOCs, and PAHs Along the U.S.-Mexico Border in ArizonaEPA Grant Number: U915924
Title: Human Exposure to Metals, Pesticides, VOCs, and PAHs Along the U.S.-Mexico Border in Arizona
Investigators: Rogan, Seamus P.
Institution: University of Arizona
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: January 1, 2001 through January 1, 2004
Project Amount: $93,093
RFA: STAR Graduate Fellowships (2001) RFA Text | Recipients Lists
Research Category: Fellowship - Public Health Sciences , Academic Fellowships , Health Effects
The National Human Exposure Assessment Survey in Arizona (NHEXAS AZ) was sponsored by the U.S. Environmental Protection Agency (EPA) and investigated total human exposure (multimedia, multipathway) to metals, pesticides, and volatile organic compounds (VOCs) in a population-based probability survey of the noninstitutionalized population of Arizona. The Arizona Border Survey (Border AZ) implemented a similar study design on a subset of Arizona's population residing within 40 km of the U.S.-Mexico border. The Children's Exposure to Pesticides Survey (CPS) also was sponsored by the U.S. EPA and investigated pesticide exposure in children under age 6 residing in an intensively farmed, largely Hispanic portion of Arizona. The objective of this research project is to generate population subgroup-specific exposure models based on the data collected in the NHEXAS AZ and Border AZ.
Population subgroups will include children, the elderly, racial and ethnic minorities, and the poor. These exposure models will be based on the extensive time activity and baseline questionnaire data that were collected with environmental and biological samples. Analyses of the variability in exposures for select subpopulations will be facilitated by the use of a geographic information system (GIS). Exposures for populations within the vicinity of toxic release inventory sites, urban landfills, or within a certain buffer distance from select major arterial roadways will be compared to "control" populations. These control populations consist of households sampled in the NHEXAS AZ and Border AZ outside of these buffer zones. I will apply these models to the CPS population to model individual child and other household member exposures. In the short term, my research project will consider how the statistical treatment of data below the analytical method detection limit affects aggregate and cumulative exposure assessment. I also will explore the relative strengths and weaknesses of incorporating GIS in exposure assessment; survey-population selection, recruitment, and tracking; data analysis; and risk communication. These analyses will inform statistical modeling of population subgroup variability in exposure to metals (Pb and As), pesticides (chlorpyrifos and malathion), and VOCs (benzene, toluene, and trichloroethylene) in the NHEXAS AZ and Border AZ. Subpopulation-specific pesticide exposure models generated using the NHEXAS AZ and Border AZ data may then be validated using CPS data.