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Updated: Jan 24, 2026
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Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether
Published on: August 17, 2019
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Legacy Polybrominated Diphenyl Ethers (PBDEs) Trends in Top Predator Fish of the Laurentian Great Lakes (GL) from
Chuanlong Zhou1, James Pagano2, Daryl J McGoldrick3
1Department of Civil and Environmental Engineering , Clarkson University , Potsdam , New York 13676 , United States.
Environmental Science & Technology
|May 30, 2019
Summary
Polybrominated diphenyl ethers (PBDEs) in Great Lakes fish initially rose, then fell, but higher brominated compounds are now increasing. This suggests ongoing environmental transformation and bioaccumulation concerns for PBDEs.
Area of Science:
- Environmental Science
- Ecotoxicology
- Chemical Contamination
Background:
- Polybrominated diphenyl ethers (PBDEs) were widely used as flame retardants and are persistent environmental contaminants.
- PBDEs have been detected across the Great Lakes (GL) ecosystem, raising concerns about bioaccumulation in top predators.
Purpose of the Study:
- To determine the concentration trends of major PBDE congeners in top predator fish (lake trout and walleye) from 1979 to 2016.
- To investigate the factors influencing PBDE trends, including production phase-outs and potential environmental transformations.
Main Methods:
- Analysis of age-normalized PBDE concentrations in fish samples collected through long-term U.S. and Canadian monitoring programs.
- Statistical trend analysis of five major PBDE congeners (BDE-47, 99, 100, 153, 154) across all five Great Lakes.
Main Results:
- PBDE concentrations in GL fish increased significantly from 1990-2000, decreased rapidly from 2000-2007, and then stabilized with smaller decreases post-2007.
- While BDE-47 decreased in most lakes, higher brominated congeners (BDE-100, 154) showed increasing trends since 2007.
- PBDE production phase-outs occurred in the U.S. (2004) and Canada (2008).
Conclusions:
- The observed PBDE trends indicate a complex dynamic influenced by historical usage, regulatory actions, and environmental processes.
- Increasing bioaccumulation of higher brominated PBDE congeners may be linked to the transformation of BDE-209 in the Great Lakes environment or food web.
- The continued presence of BDE-209 suggests that stable total PBDE concentrations in fish may persist for an extended period.
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