EPA Science Inventory

Web-enabling Ecological Risk Assessment for Accessibility and Transparency


Purucker, Tom. Web-enabling Ecological Risk Assessment for Accessibility and Transparency. Presented at SETAC North America: Workshop, MECHANISTIC EFFECT MODELS FOR ECOLOGICAL RISK ASSESSMENT: RECENT PROGRESS AND FUTURE DIRECTIONS, Nashville, TN, November 18 - 22, 2013.


Ecological risk methods and tools are necessarily diverse to account for different combinations of receptors, exposure processes, effects estimation, and degree of conservatism/realism necessary to support chemical-based assessments. These tools have been continuously developed since the early 1980s and are currently accessible through a number of software platforms (e.g., DOS-based FORTAN executables, spreadsheet-based calculations, form-based Windows programs) that can lead to inefficiencies and inconsistencies when used together to inform an assessment. Recent advances in cloud-based computing provides an opportunity to integrate commonly used ecological risk models as a web application dashboard that allows for the modular execution of individual models as well as the simultaneous execution of multiple models in a serial or parallel manner. We have created an integrated web-based tool, the übertool (http://www.ubertool.org), designed to run EPA models that estimate exposure doses and ecological risks under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Endangered Species Act (ESA). These models include a number of aquatic, terrestrial, and atmospheric deposition fate and transport models used to estimate pesticide exposures and effects for a range of ecological receptors. We have also extended the übertool's web-based framework to create the untertool (http://untertool.appspot.com), which gives examples of population dynamic models that are often used for educational and research purposes. By aggregating such models into a virtual dashboard and providing them as web services, we hope to help narrow the gap between ecological hazard assessment/risk quotient approaches that address individual effects endpoints and the difficult task of reliably assessing ecological endpoints at the population level. Closing this gap is necessary to create a common, scientifically credible approach to resolve such endpoint assessment discrepancies and is a current focus of interagency discussion in the US with respect to ecological risk activities in support of the Endangered Species Act.


There are various pressures to develop new approaches to the ecological risk assessment of chemicals. On the one hand there is pressure to test more chemicals, leading to economic pressures to reduce the costs of tests and to speed them up, and also ethical pressures to reduce the use of animals in testing. One response to these pressures is to make better use of observations on suborganismal responses arising from chemical perturbations to make an assessment of the likelihood of impact on targets of concern. Frameworks such as Adverse Outcome Pathway (AOP) take this approach. This framework offers the promise of identifying mechanisms that are responsive to chemical perturbation and of building in vitro testing methods around them. On the other hand, there are also calls for developing more holistic risk assessments that are more in tune with the needs of risk management, that relate more obviously to the objects of protection, and that thus express impacts in terms of health and/or ecosystem services. Finally, there are calls for approaches that make more explicit links between exposure and effects and that move away from expressing risks in terms of simple thresholds and toward outputs that can better inform management decisions. Mechanistic effect models encompass a broad range of quantitative tools to address these issues and support the quantification of risks for tested and untested chemical stressors. Speakers representing the academia, regulatory agencies, and industry tripartite are participating in a workshop intended to discuss how lessons learned from recent and ongoing initiatives in Europe and North America could facilitate the development and implementation of predictive modeling tools in the regulatory risk assessment of chemicals. The workshop is a mix of invited talks and panel discussions where audience participation will be encouraged.


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Record Details:

Start Date: 04/28/2014
Completion Date: 04/28/2014
Record Last Revised: 04/28/2014
Record Created: 04/28/2014
Record Released: 04/28/2014
OMB Category: Other
Record ID: 274438