The Big Picture of Great Lakes Mercury Pollution

A transdisciplinary team examined regulatory impacts on Great Lakes mercury, focusing on an Upper Peninsula tribal community with high fish consumption.

Great lakes, source: Wikimedia Commons

Mercury is a widespread environmental toxicant and pollutant that travels up the food chain onto people's dinner plates. Although a global issue, mercury regulations vary worldwide. Depending on where one lives in relation to mercury emissions, regional remediation makes minimal impacts for local fish consumption advisories.

This is particularly true in a sensitive landscape like Michigan's Upper Peninsula, where nearly 80 percent of inland lakes are impaired.

For the Keweenaw Bay Indian Community (KBIC), the problem culminates in the question, when can we eat the fish? A simple answer is elusive, but a study led by Michigan Technological University did provide insights as to what must be done to make the fish safe to eat.

The KBIC's question helped guide biogeochemical modelers, environmental engineers and social scientists to bridge global-chemical transport models and the local impacts on the KBIC and Michigan's Upper Peninsula. The study was published this week in the Royal Society of Chemistry’s peer-reviewed journal Environmental Science: Processes & Impacts (DOI: 10.1039/c7em00547d), and the work is part of a National Science Foundation program looking at the dynamics of coupled natural and human systems.

Sensitive Communities

Mercury is an atmosphere-surface exchangeable pollutant (ASEP) along with polychlorinated biphenyl (PCB) compounds, polycyclic aromatic hydrocarbon (PAH) compounds and other persistent organic pollutants (POPs). ASEP molecules are invisible, tasteless world-hoppers that can travel great distances.

Eventually, they make their way to the Great Lakes where they move through the air, landscape, water and animals. Researchers can describe ASEP movement and impacts through policy, socioeconomic pressures, ecosystem services, stressors like climate change and land use as well as biogeochemical cycling. The study's lead researcher is Judith Perlinger, professor of environmental engineering at Michigan Tech. She says the project is an example of using state-of-the-art science to answer a community-relevant question.

"We're taking phenomena that act on a global scale and predicting what they will do," Perlinger says, adding that working with the KBIC is a key piece of the project. "Clearly the issue matters to them, so how can we make the science relevant to them?"

To do so, take a big team: Six institutions, 36 researchers and 11 partnering organizations. Perlinger‘s team uses GEOS-Chem, a global three-dimensional Eulerian chemical transport model. It has been widely used to better understand tropospheric chemistry and composition. For ASEPs, GEOS-Chem sorts through the emission sources, migration, exchange rates and resting places of the pollutants and is coupled with mass balance modeling to understand the aquatic dynamics of the system.

Read full article: Michigan Tech

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Taxonomy

• Decontamination
• Contaminant Removal
• Ecosystem Management
• Pollution
• Lake Management
• Heavy metals
• Pollution
• Environmental