Biomonitoring And Bioindicators For Human And Ecological HealthJoanna Burger, Ph D.
The operable unit approach at the DOE manages small hazardous waste sites without taking into account the vastness of their large sites. The Ecological Health Group is developing an overall biological monitoring plan that includes all levels of ecological organization, from single species indicators to ecosystem measures, and that includes bioindicators for both human and non-human receptors. Suitable bioindicators include Mourning Doves, Raccoons and Fish; the general characteristics of other species that make them useful indicators for assessing both human and ecological health are given, as well as other measures for evaluating ecosystem complexity. There are three key characteristics for selecting bioindicators for a monitoring plan: biological relevance, methodological relevance, and societal relevance. An indicator which fails to fulfill these is not likely to be useful for stakeholders or to be cost-effective, and is likely to be abandoned
Generally risk assessors and managers examine either ecological health using bioindicators, or human health using biomarkers of exposure or effect. The Department of Energy is faced with determining cleanup standards, future land uses, and stewardship options for their lands. The Ecological Health Task group suggests that it is possible and advantageous to develop bioindicators that can be used to assess exposure and effect for both human and non-human receptors. There is a need for a holistic environmental monitoring plan that can be used both to aid in remediation decisions, to provide credible input to exposure assessment models, and to evaluate the success of remediation, restoration, and stewardship.
Biomonitoring plans and bioindicators can be developed that assess both the health of humans and of ecosystems at different levels of organization.
Overview of Bioindicators
Bioindicators can be used cross-sectionally to assess the status of an ecosystem or longitudinally in a monitoring framework (Piotrowski, 1985; Peakall, 1992, Burger 1999 a,b). Data on long term trends can be used to both assess the well-being of the species in question, as well as to ascertain whether there is cause for concern about future health outcomes of other trophic levels (including humans, Fig. 1).
Ecological health can be viewed in terms of ecosystems, whereby structural and functional characteristics are maintained (Fig. 2). Ecological health can be expanded to include many aspects of human health and well-being (Fig. 3). In either case, the outcomes are similar: healthy ecosystems must be maintained in order for humans to receive goods and services from those ecosystems.
Bioindicators that are developed specifically to assess human exposure (e.g., through the food chain) can also be indicative of the health of the organisms themselves (Burger et al. 1997), and more generally of the health of the ecosystem (Wilson, 1994).
Bioindicators and indices can then be developed to examine higher levels of organization (populations, communities, ecosystems). Such indicators must be relevant (Table 1).
Key features of a biomonitoring plan to inform decisions about remediation and restoration of DOE lands, as well as to evaluate the efficacy of remediation.
Raccoons, Doves And Fish
Some bioindicators that are high on the food chain are most comparable to humans and most sensitive to stressors, but are often rare and difficult to study. Others that are at an intermediate trophic level may be consumed by humans, hence be directly relevant to human exposure. Indicator species that are lower on the food chain can be used to indicate potential damage to higher trophic level organisms within ecosystems, as well as to humans who consume them.
Three species that can be used to examine both ecological and human health include Mourning Doves, Raccoons, and fish (Burger et al. 1997, 1998, Kennamer et al. 1998, Gaines et al. ms.) These are useful because they are common, widespread, of interest to the public, and consumed by humans (Figs. 4-6).
Biomonitoring For Ecological Complexity
It is essential to include indicators or metrics for all levels of ecological organization. The biomonitoring plan below was developed for the Savannah River Site, in collaboration with scientists at the Savannah River Ecology Laboratory, and with input from a variety of stakeholders including the DOE, U.S. Environmental Protection Agency, state regulators, Center for Disease Control Health Effects Subcommittee, the Citizen's Advisory Board for SRS, fishermen and hunters, other recreationists, and the general public (Burger 1997, Burger et al. 1997,1998,in press, ms). Stakeholder input is a key element to selecting indicators that are of interest and relevant to the public, as well as to scientists and regulators. This plan is a work-in-progress, and will be modified as more is learned about on-site stressors, including radionuclides, contaminants and physical disturbances (Table 2), and needs for exposure assessment.
Table 2: Biomonitoring plan for DOE sites, particularly those with wetlands, streams and woodland habitats.
GO BACK TO Responsive Science
Managers and other decisions-makers are looking for good data to help them make wise decisions (Johnson, 1993) about remediation, land use and stewardship. Bioindicators and indices must be developed that can be easily and credibly employed, while providing scientifically defensible data for decision-making. Ecologists and human health risk assessors can optimize public support for biomonitoring plans by employing bioindicators that can be used for assessing both human and ecological health, and augmenting these with indicators for higher levels of ecological organization. This information can be used for assessing human and ecological health, for understanding fate and transport, and ultimately, for decisions about land use, stewardship, and long term biomonitoring (Fig. 7), before, during and after remediation (fig. 8).
An Overview Of Cresp Interactions
Temporal Uses For Decision-Making
Collaborators On These Projects
The research reported herein was conducted under Rutgers protocol 97-017 and 86-016, and was funded by the Consortium for Risk Evaluation with Stakeholder Participation (CRESP) through the Department of Energy cooperative agreement (AI # DE-FC01-95EW55084), by NIEHS (ESO 5022) and the Environmental and Occupational Health Sciences Institute.