Toxic Substances: Evaluation of Contaminants and their Potential Biological Effects in Great Lakes Tributaries

Science Center Objects

The objective of this project is to Identify emerging contaminants and assess impacts on Great Lakes fish and wildlife.

The USGS is participating in a multi-agency effort to assess the impact of pesticides, pharmaceutical compounds, polycyclic aromatic hydrocarbons, flame retardants, ingredients in plastics, and ingredients in personal care products on biological communities in the Great Lakes Tributaries. On an annual basis, one or more specific classes of contaminants have been chosen for in-depth study. Prioritization of chemicals based on the potential for adverse biological effect will be provided through collaborations with the U.S. Environmental Protection Agency (EPA), the U.S. Army Corps of Engineers (USACE), The National Oceanic and Atmospheric Administration (NOAA), and the U.S. Fish and Wildlife Service (USFWS). Chemical surveillance in Great Lakes tributaries was completed from 2010-2018.  Initially the study focused on a wide variety of watersheds covering variable land uses monitored for a general suite of chemicals including those from urban, agricultural, industrial, commercial, and residential uses. From this data, additional surveillance was designed to evaluate classes of chemicals that appeared to be of greatest concern including pesticides and their degradation products in water (16 sites, 2016), polycyclic aromatic hydrocarbons (PAHs) in sediment (71 sites, 2017), pharmaceuticals in water (44 sites, 2018), and per- and poly-fluoroalkyl substances (PFAS) in water and sediment (85 sites, 2017-2018).

Analysis of resulting data has focused on identifying the frequency and magnitude of chemical presence and evaluation of the potential for biological effects. Techniques to evaluate bioeffects have included traditional approaches as well as more modern techniques with the goal to expand the number of chemicals for which evaluation data is available. Publications to date have evaluated a suite of chemicals with 15 different chemical classes and have highlighted a subset of chemicals that have the greatest potential to pose a hazard including 4-nonylphenol (detergent metabolite) , bisphenol A (component of plastics and other products), metolachlor, atrazine, DEET (pesticides), caffeine, Tris(2-butoxyethyl) phosphate, tributyl phosphate, triphenyl phosphate (flame retardants), benzo(a)pyrene, fluoranthene (PAHs), and benzophenone (personal care product). Additional evaluation of a more comprehensive suite of pesticides, PAHs, pharmaceuticals, and per-and poly-fluoroalkyl substances.



  • Baldwin, A. K., Corsi, S. R., De Cicco, L. A., Lenaker, P. L., Lutz, M. A., Sullivan, D. J., & Richards, K. D. (2016b). Organic contaminants in Great Lakes tributaries: Prevalence and potential aquatic toxicity. Science of The Total Environment, 554–555, 42–52.
  • Baldwin, A. K., Corsi, S. R., & Mason, S. A. (2016c). Microplastics in 29 Great Lakes tributaries (2014-15): U.S. Geological Survey data release.
  • Baldwin, A. K., Corsi, S. R., & Mason, S. A. (2016d). Plastic Debris in 29 Great Lakes Tributaries: Relations to Watershed Attributes and Hydrology. Environmental Science & Technology, 50(19), 10377–10385.
  • Corsi, S. R., Dila, D. K., Lenaker, P. L., Baldwin, A. K., Bootsma, M. J., & McLellan, S. L. (2018). Regression models and associated data for describing variability of host specific bacteria fluxes in eight Great Lakes tributaries, 2011-2013 [Data set]. U.S. Geological Survey.
  • Corsi, S.R., De Cicco, L.A., Villeneuve, D.L., Blackwell, B.R., Fay, K.A., Ankley, G.T., Baldwin, A.K., 2019. Prioritizing chemicals of ecological concern in Great Lakes tributaries using high-throughput screening data and adverse outcome pathways. Science of The Total Environment 686, 995–1009.
  • Dila, D. K., Corsi, S. R., Lenaker, P. L., Baldwin, A. K., Bootsma, M. J., & McLellan, S. L. (2018). Patterns of Host-Associated Fecal Indicators Driven by Hydrology, Precipitation, and Land Use Attributes in Great Lakes Watersheds. Environmental Science & Technology.
  • Lenaker, P. L., Corsi, S. R., Borchardt, M. A., Spencer, S. K., Baldwin, A. K., & Lutz, M. A. (2017). Hydrologic, land cover, and seasonal patterns of waterborne pathogens in Great Lakes tributaries. Water Research, 113, 11–21.



This effort has produced data on more than 600 different chemicals in Great Lakes tributaries. Several publications have been produced to evaluate these chemicals for potential biological impact, prioritizing results by chemicals of greatest concern, the sites in which these chemicals occur, and the potential biological processes that are likely to be influenced. This project is providing rare information on contaminants of emerging concern to narrow down the list of chemicals present to those that that have the greatest likelihood to pose an ecological hazard.


  • Design and implementation of the study design have been a result of regular collaboration with USEPA, USACE, NOAA, and USFWS.
  • More in-depth collaboration with USEPA researchers has led to the release of a software product (see toxEval link above) that allows for efficient assessment of chemical concentrations for estimating potential biological effects using measured contaminant concentration data in various environmental media as well as two publications using these techniques.
  • A Collaboration with State University of New York Fredonia resulted in a publication defining microplastics contamination in Great Lakes tributaries.