Research Project 6
Characterization of Exposures of Urban and Rural Cohorts to Airborne PCBs
In this project Dr. Peter Thorne is assessing exposures to atmospheric PCBs among a cohort of children and their mothers in a contaminated area where dredging of PCB-laden sediments will occur during the study period. PCB concentrations are measured through repeated air sampling inside and outside of homes and local schools. Blood samples are collected annually and assayed for PCB congeners. These data are compared to a rural site to characterize high and low exposure residential cohorts. The urban site (East Chicago, IN) has a legacy of PCB contamination from intense past industrial activity whereas the rural site (Columbus Junction, IA) is without local sources of PCBs. The 2010-15 project funding period continues four original aims and pursues two new aims:
•Aim 1. Establish a residential cohort in East Chicago and a rural residential cohort in Columbus Junction
•Aim 2. Measure emissions and exposures of atmospheric PCBs at homes and schools in these communities
•Aim 3. Gather demographic, residential, occupational, activity and dietary information by questionnaire
•Aim 4. Analyze data from these cohorts and develop an exposure model for the atmospheric PCB congeners.
Aim 1 has been achieved but the research group is expanding the cohort to increase power and span the time before and during the dredging. Aim 2 and Aim 3 are ongoing. The researchers are continuing to measure subjects' PCB exposures, collect blood samples and administer questionnaires. They have begun Aim 4 with analysis of survey data and congener-specific PCBs.
Two new aims are being done in this funding period:
• Aim 5. Measure congener-specific hydroxy metabolites of PCBs in subjects' biobanked extracted and derivitized blood samples.
•Aim 6. Adapt a bioaccumulation model to predict the PCB body burden in subjects breathing air with measured PCBs levels and compare modelled data with measured data.
Five hypotheses are being tested:
• H1: East Chicagoans have significantly higher exposures than rural Iowans.
•H2: East Chicagoans have blood levels of atmospheric PCB congeners than rural Iowans.
•H3: Adolescent's burdens of PCB congeners are significantly correlated with those of their mothers.
•H4: East Chicagoans will experience increased exposures with the dredging of Indiana Harbor and Ship Canals and filling of the Confined Disposal Facility.
•H5: Bioaccumulation models can predict the relative body burdens of PCBs using measured air data and dietary questionnaire data.
Video of the November 18, 2008 visit to isrp laboratories by Columbus Junction 7th graders:
East Chicago Schools:
Columbus Junction Schools:
Project Leader: Peter S. Thorne, PhD
Dr. Thorne is a professor of toxicology in the Department of Occupational and Environmental Health at the University of Iowa with a secondary appointment in the Department of Civil and Environmental Engineering. He will serve as a principal investigator for this study. He will have overall responsibility for the project and will serve as the primary contact with other Project and Core Leaders in the isrp. Dr. Thorne will supervise all field and laboratory staff in Iowa and East Chicago. He has worked successfully with the community advisory boards and schools in Columbus Junction and East Chicago, and will oversee the enrollment of the cohorts for the project. Dr. Thorne will work with Kai Wang and co-investigators on data analysis and the drafting of presentations, progress reports and publications.
Co-Project Leader: Keri C. Hornbuckle, PhD
Dr. Hornbuckle, professor of environmental engineering at the University of Iowa, will provide advice on fabrication and deployment of the passive monitors and high volume samplers, and she will provide guidance in the analysis of PCB congener-specific data. Her experience in measuring and modeling PCBs in urban and rural settings will be drawn upon in the interpretation of exposure data.
Co-Project Leader: Kai Wang, MA, PhD
Dr. Wang, associate professor in the Department of Biostatistics at the University of Iowa, will will participate in discussions regarding study design, cohort recruitment, and data management. He will provide major input on all data analysis and will develop the multiple linear regression models and multilevel analysis for Specific Aims 6 and 7.
Co-Project Leader: David Osterberg, MS, MA
Clinical Associate Professor, Department of Occupational and Environmental Health, College of Public Health, The University of Iowa
Co-Project Leader: Fredric Gerr, MD
Professor, Department of Occupational and Environmental Health, College of Public Health, The University of Iowa