PARENT SESSION
WA9 - Role of Biomarkers/Bioindicators in Ecological Risk Assessment
Chair: Adams, Marshall1, 1 PO Box 2008, Bld. 1505, Oak Ridge, TN, USA
Co-chair: Zelikoff, Judith2, 2 57 Old Forge Rd., Tuxedo, NY, USA
8:00 AM to 12:00 PM - Wednesday, 20 November 2002
Room Ballroom E
(564) Role of Biomarkers and Bioindicators in Ecological Risk Assessment.
Adams, Marshall*,1, 1 Oak Ridge National Laboratory, Oak Ridge, TN, USA
ABSTRACT- Most Ecological Risk Assessment (ERA) models include a variety of endpoints such as chemical criteria and various bioassay tests. However, these models rarely incorporate a suite of biological responses that represent a wide range of spatial and temporal sensitivities and specificities to different stressors. Biomarkers of environmental stress at lower levels of biological organization such as the mixed function oxidase (MFO) enzymes and DNA integrity provide direct evidence of exposure to chemical stressors while intermediate-level responses such as histopathological, bioenergetic, immunological, and reproductive changes can help predict stress effects at the individual and population levels. Responses at the lower levels of biological organization (biomarkers) have the primary advantage of being relatively sensitive and also somewhat specific to certain types of stressors thus serving as early warning indicators of impaired health to wildlife species. Biomarkers, however, cannot be considered useful bioindicators of health on wildlife unless they are causally linked to ecologically relevant responses such as population or community-level endpoints. Conversely, responses at higher levels of organization (bioindicators) are relatively insensitive to stressors and provide little insight into the mechanistic basis of observed effects. The primary advantages of bioindicators is that they integrate the combined effects of multiple stressors over time and represent more ecological relevant endpoints. Even though bioindicators are more directly applicable for addressing environmental management and regulatory issues, a proper mix of both biomarkers and bioindicators should be used in the ERA process.. This session consists of a series of presentations that address the role of various biomarkers and bioindicators in the ERA process including the advantages and limitations of using various biocriteria in ERA.
Key words: biocriteria, ERA, biomarkers, bioindicators