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About EPA

About the Great Lakes Toxicology and Ecology Division

On This Page:

What We Do
Our Research


What We Do

The Great Lakes Toxicology & Ecology Division (GLTED) focuses on developing new methods to predict the effect of chemicals on our nation’s freshwater ecosystems. The Division incorporates traditional and predictive toxicity using advanced tools to produce science to inform ecological risk assessments of chemicals by EPA’s Program Offices and Regions.

GLTED primarily focuses on freshwater coastal ecology, linking the ecological integrity of receiving waters to watershed effects, and developing indicators and sampling protocols for freshwater ecosystem assessments. GLTED uses an array of factors to assess and predict outcomes of clean up and revitalization efforts. Intrinsic to this division’s mission is building the functional resiliency of watersheds and coastal systems to human-driven flows of chemicals, sediment, and invasive species. 

Our Research



Dale Hoff, Director

  • Phone: 218-529-5011
  • Email:  Dale Hoff (

Mary Hautajarvi, Program Operations Staff Chief



  • Ecosystem Services Branch
    The Ecosystem Services Branch (ESB) quantifies the outputs of freshwater ecosystems and how they contribute to human well-being and social welfare. ESB develops ecological, biophysical and socioeconomic indicators of ecosystem services, create models for translating ecosystem structure and function into human benefits which are used to quantify tradeoffs among services resulting from management actions including environmental remediation and restoration. 
  • Systems Toxicology Branch
    The Systems Toxicology Branch (STB) conducts research in pathway-based approaches to predicting toxic effects of chemicals in ecological receptors.  Areas of emphasis include adverse outcome pathway development and quantification, extrapolation across chemicals, species and biological levels of organization and development of quantitative structure activity models.
  • Molecular Indicators Branch
    The Molecular Indicators Branch (MIB) uses bioinformatic and molecular biology approaches to reduce uncertainty in assessing the ecological risk posed by single chemicals, chemical mixtures, and sources of chemical exposure.  MIB research characterizes responses in test species and in vitro systems across different levels of biological organization, from the intracellular level to the whole organism focused on the complexity of real-world exposures.
  • Translational Toxicology Branch
    The Translational Toxicology Branch (TTB) conducts research providing expertise, methods and models for determining chemical effects in ecological receptors and interpreting those effects within the context of ecological risk assessment and other regulatory applications.  Areas of emphasis include dosimetry prediction and modeling, bioavailability, bioaccumulation, development of toxicity test methods, synthesis of toxicity test results, and population level effects of chemicals.
  • Watersheds and Water Resource Branch
    The Watersheds & Water Resource Branch (WWRB) conducts research that links the ecological sustainability of receiving waters to watershed integrity. WWRB integrates new technology with evolving ecological methods in a systems approach to understanding the impacts of anthropogenic stressors on diverse water body types and multiple spatial scales.


Main Office Location

US EPA ORD Center for Computational Toxicology and Exposure
Great Lakes Toxicology and Ecology Division
6201 Congdon Boulevard
Duluth, MN 55804