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Introduction to this Effort

In 2003, an EPA sponsored workshop convened by the Society for Environmental Toxicology and Chemistry (SETAC) gathered scientists from across the United States and several other countries to devise a national mercury monitoring program. A roadmap for a comprehensive national mercury monitoring program emerged from this workshop, detailed in a peer-reviewed journal article published in 2005 and a 2007 book.

At a follow-up National Mercury Monitoring Workshop in May 2008, U.S. and Canadian scientists from state, federal, tribal, academic, and private institutions agreed upon the overall goal of a network:

"To establish an integrated, national network to systematically monitor, assess, and report on policy-relevant indicators of atmospheric mercury concentrations and deposition, and mercury levels in land, water, and biota in terrestrial, freshwater, and coastal ecosystems in response to changing mercury emissions over time."

Workshop scientists considered the conceptual framework for a mercury monitoring network ("MercNet"), and agreed on several monitoring design elements:

  • A national distribution of sites to understand the sources, consequences, and changes in U.S. mercury pollution;
  • A network of 10-20 intensively monitored sites to establish cause and effect relations between mercury pollution and ecosystem change and to provide data for developing and refining predictive models;
  • A group of less intensively studied "cluster" sites surrounding each intensive site to provide a general understanding of the range of ecosystem responses within a region;
  • Monitoring of mercury in air, water, sediments, fish, and wildlife at each site.
  • A network operated for 10-40 years, a timeframe needed to quantify the range of responses expected among different ecosystems; and
  • A network that builds on existing monitoring efforts, where possible, to maximize information, benefits and coordination, and efficiency.

Collaboration and partnerships among existing mercury scientists and monitoring programs are integral to MercNet. A broad cross-section of agencies and institutions are working to coordinate mercury monitoring activities, building on current efforts and encouraging new collaborative relationships.

The May 2008 National Mercury Monitoring Workshop was an important step in building broad community support for a comprehensive, integrated monitoring network. This workshop was part of an ongoing effort to enhance mercury monitoring in the United States through coordination of existing monitoring, and, should new funding sources become available, implementation of new and coordinated, policy-relevant monitoring efforts.

For more information

, Syracuse University, Syracuse, New York
, BioDiversity Research Institute, Gorham, Maine
, National Atmospheric Deposition Program, Champaign, Illinois
, University of Wisconsin-La Crosse, La Crosse, Wisconsin

Federal Agency Contacts



Mason RP, Abbott ML, Bodaly RA, Bullock Jr. OR, Driscoll CT, Evers D, Lindberg SE, Murray M, Swain EB. 2005. Monitoring the response of changing mercury deposition. Environ. Sci. Technol. 39:14A-22A.

Harris R, Krabbenhoft DP, Mason R, Murray MW, Reash R, Saltman T. 2007. Ecosystem responses to mercury contamination: indicators of change. SETAC, Boca Raton, FL.