Biomarkers for Organochlorine-Associated Immunosuppression in Birds: Field Investigations in the Great Lakes and Laboratory StudiesEPA Grant Number: R825216
Title: Biomarkers for Organochlorine-Associated Immunosuppression in Birds: Field Investigations in the Great Lakes and Laboratory Studies
Investigators: Grasman, Keith A.
Institution: Wright State University - Main Campus
EPA Project Officer: Hahn, Intaek
Project Period: December 1, 1997 through November 30, 2001
Project Amount: $488,000
RFA: Exploratory Research - Early Career Awards (1996) RFA Text | Recipients Lists
Research Category: Early Career Awards , Environmental Justice
Description:The objectives of this project are 1) to elucidate recently documented associations between environmental contaminants and immunosuppression in fish-eating birds of the Great Lakes by conducting field and laboratory studies that evaluate new immunological biomarkers and the interactive effects of PCB congeners; 2) to investigate the occurrence of infectious diseases in fish-eating birds of the Great Lakes; 3) to elucidate the relevance of immunological biomarkers by simultaneously measuring suppression of these biomarkers and susceptibility to infections; and 4) to investigate population level effects associated with contaminants in Great Lakes birds by continuing long-term reproduction and banding studies.
Fish-eating birds such as gulls and terns are effective "sentinel species" for assessing toxic effects of contaminants on the health of the Great Lakes ecosystem. Numerous studies have shown associations between organochlorines and reproductive, developmental, and population-level problems in these species. PCBs and TCDD cause immunosuppression and increase susceptibility to infections in laboratory animals at concentrations comparable to those in wildlife at some Great Lakes sites. Immunosuppression recently has been documented in herring gull and Caspian tern chicks at highly contaminated sites in the Great Lakes.
This research project will integrate laboratory and field studies to achieve the objectives stated above. In the first phase of the project, a battery of immunological tests will be used to measure immune function in chicken embryos and chicks from eggs injected with combinations of PCB congeners. The same immunological biomarkers will be measured in wild herring gull embryos and herring gull and Caspian tern chicks in the Great Lakes. Study sites will be distributed across a gradient of organochlorine contamination. Disease surveys will be conducted in wild colonial waterbirds to determine the morbidity and mortality associated with important diseases at the study colonies. The last phase of the project will calibrate specific levels of suppression of immunological tests to decreased resistance to infections. Using an important pathogen identified by the disease surveys in wild birds, disease challenge experiments will be conducted in PCB-exposed chickens in which immune function variables also are measured.
The results of this study will provide new immunological methods for use in wild species and will help elucidate the mechanisms of PCB-induced immunosuppression in birds. This study will help establish the relevance of changes in immune function tests by simultaneously challenging the birds with infectious microorganisms. It will provide methods and data for wildlife biomonitoring, helping environmental agencies identify problem sites and follow recovery after pollution reduction.