Science Center Objects

The USGS, federal agencies, and their partners will continue to further evaluate emerging contaminants that have the greatest potential to adversely impact Great Lakes fish and wildlife – impacts which may also result in ecological, economic and recreational consequences. Federal agencies will assess the extent to which identified risks may impede environmental quality and resource management goals. Agencies and their partners will conduct laboratory and/or field studies to evaluate biological effects from chemical mixtures, evaluate long term exposure of fish to contaminants, conduct additional field sampling where effects are being observed and sample other high priority wildlife such as migratory birds, mussels and amphibians. These projects will be evaluated on an annual basis and the results will be used to prioritize the design and implementation of future laboratory and field studies.

Mercury Sampling Crews on boat in pacific ocean

Mercury Sampling Crew. (Public domain.)

Mercury Monitoring Program

Mercury is a toxic chemical of significant concern in the Great Lakes region that was initially believed to enter the lakes only through watershed runoff.  Thanks to GLRI funding, USGS scientists identified atmospheric and industrial mercury as previously unrecognized sources of methyl-mercury (the mercury that can be found in the fish we eat). The USGS and the University of Wisconsin-Madison followed up on this finding with development of a tool that “fingerprints” each of the mercury sources. Determining where the mercury comes from is important, because it informs decisions designed to minimize it.

Science Support at Mercury-Contaminated AOC Sites

This work seeks to provide science that informs restoration managers at AOC sites to better understand the effectiveness of various remediation procedures (e.g., dredging, sand capping, or air emission reductions) for reducing mercury bioaccumulation and ultimately the issuance of BUIs.

Mercury Source Fingerprinting in the Great Lakes

Mercury exposure to fish, wildlife and humans across the Great Lakes is a significant concern, resulting in the issuance of fish consumption advisories on all five lakes. This project seeks to use mercury source fingerprinting methods to establish the originating source of mercury to fish and humans inhabiting the Great Lakes region.


Contaminants in Great Lakes Tributaries

Glass column filled with XAD resin used in large volume PCB monitoring

Glass column filled with XAD resin used in large volume PCB monitoring.(Public domain.)

The USGS is participating in a multi-agency effort to achieve this objective. On an annual basis, one or more specific classes of contaminants are chosen for in-depth study. Support from GLRI provided in the 2017 fiscal year will be used for evaluation of pharmaceutical compounds and per- and polyfluoroalkyl substances in multiple locations within watersheds that drain to each of the Great Lakes. Prioritization of chemicals based on the potential for adverse biological effect will be provided through collaborations with USEPA, the U.S. Army Corps of Engineers, NOAA, and the Fish and Wildlife Service. 

Lake Michigan Tributary Polychlorinated Biphenyl (PCB) Monitoring

Polychlorinated Biphenyl (PCB) contamination of Lake Michigan fish was first detected in the 1960s. Since that time, much effort has been put into reducing PCB inputs to Lake Michigan. This project was aimed at documenting the reductions in PCB loads from tributaries to Lake Michigan. Decreases in tributary loads will lead to lower concentrations of PCB in Lake Michigan sediment, water, and fish.
This project collected high-volume water samples at 5 Lake Michigan Tributaries; the samples were analyzed by researchers at Indiana University for PCBs as well as a variety of flame retardants.
Decreases in median PCB concentration and annual mass loading were observed for all 5 tributaries relative to previous sampling programs.
For example, the Lower Fox River at Green Bay, Wisconsin was estimated to be contributing about 200 kg/yr of PCB to Lake Michigan in 1994-1995; estimates from 2005-2006 put the Fox River contribution at about 130 kg/yr. Our estimates of PCB load for the Fox River put the contribution in 2015 at about 90 kg/yr.
Similarly, the Indiana Harbor and Ship Canal was estimated to contribute about 32 kg/yr of PCB to Lake Michigan in 1994-1995. The 2015 estimate is about 11 kg/yr.

Chemicals of Emerging Concern (CEC) Surveillance Program

USGS is participating in a multi-agency federal partnership to evaluate contaminants in Great Lakes tributaries and their potential biological impacts. Results from this effort will serve as base information and will provide an opportunity for long-term evaluation of impacts of land use changes and restoration efforts on CECs. In addition, results from genetic and physiological responses of birds to contaminants in concert with environmental contaminant information can directly inform natural resource and public health agencies on underlying factors for environmental health and human health outcomes.