Research

Mercury and POPs are global environmental pollutants influenced by human activities. The dominant source of anthropogenic mercury emissions is burning of coal, but industrial processes such as metals production and intentional uses of mercury are also sources. POPs can be intentionally produced (for use as pesticides and industrial chemicals) or emitted as byproducts of combustion or other industrial processes. Both mercury and POPs accumulate in food webs, posing risks to human health and the environment.

Despite increasing attention to mercury and POPs as environmental problems, there are significant outstanding scientific questions regarding their behavior and chemistry in the atmosphere and biosphere. For mercury, one area of uncertainty is the atmospheric redox chemistry between gaseous elemental mercury (Hg(0)), which has a mean atmospheric lifetime of 0.5-2 years and is thus transported globally, and divalent mercury (Hg(II)), which is water-soluble and thus subject to dry and wet deposition to ecosystems. An issue for POPs is constraining the pathways of transport to the Arctic environment. Common to both Hg and POPs is constraining the cycling between the atmosphere and land and ocean reservoirs, and the extent to which the legacy of past anthropogenic activities affect current pollution. From a policy perspective, a key objective is to quantify the extent to which domestic and international emissions influence present-day deposition (and thus ultimately human exposure), so that emissions reduction activities can be implemented effectively. In addition, we are interested in constraining potential future changes in exposure due to climate change.

For more information:

N.E. Selin, E. M. Sunderland, C.D. Knightes, and R.P. Mason. 2009. "Source attribution of mercury exposure for U.S. seafood consumers: Implications for policy." Environmental Heatlh Perspectives, in press, doi:10.1289/ehp.0900811[pdf].

N.E. Selin and D.J. Jacob. 2008.“Seasonal and spatial patterns of mercury wet deposition in the United States: Constraints on the contribution from North American anthropogenic sources.” Atmospheric Environment, 42, 5193-5204, 2008, doi:10.1016/j.atmosenv.2008.02.069. [pdf]

N.E. Selin, D.J. Jacob, R.M. Yantosca, S. Strode, L. Jaeglé, and E.M. Sunderland. 2008. "Global 3-D land-ocean-atmosphere model for mercury: present-day vs. pre-industrial cycles and anthropogenic enrichment factors for deposition," Global Biogeochemical Cycles, 22, GB2011, doi:10.1029/2007GB003040. [pdf]

S. Strode, L. Jaeglé, D.A. Jaffe, P.C. Swartzendruber, N.E. Selin, C. Holmes, and R.M. Yantosca. 2008. “Trans-Pacific transport of mercury.” Journal of Geophysical Research-Atmospheres,113, D15305, doi:10.1029/2007JD009428. [pdf]

N.E. Selin, D.J. Jacob, R.J. Park, R.M. Yantosca, S. Strode, L. Jaeglé and D. Jaffe, 2007. “Chemical cycling and deposition of atmospheric mercury: Global constraints from observations.” Journal of Geophysical Research-Atmopsheres, 112, D02308, doi:10.1029/2006JD007450. [pdf]

Funding Sources:

"CAREER: Understanding Chemistry, Transport and Fate of Mercury and Persistent Organic Pollutants through Global Atmospheric Modeling," U.S. National Science Foundation, 3/1/11-pres. [html]; MIT Research Support Committee James H. Ferry Fund for Innovation in Research Education (9/2010-9/2011); MIT John Reed UROP Fund (Fall 2010); U.S. Environmental Protection Agency Science to Achieve Results (STAR) Graduate Research Fellowship, "Mercury Rising and Falling: Exploring Mercury Cycling through Atmosphere and Biosphere," 9/05-11/07 [html];

People: Noelle Selin, Carey Friedman, Shaojie Song, Colin Pike-Thackray

Science, Policy and Sustainability Decision-Making

Our research in this area focuses on the interactions between science and policy on environmental issues. We are interested in the general question of how models and quantitative information can best be used to support sustainability decision-making. One topic which we address specifically is the challenge of devising scientifically-sound, precautionary policies on hazardous substances, including toxic chemicals and heavy metals. Our work has addressed the ways in which scientific assessment processes have been influential in international policy and negotiating processes on persistent organic pollutants (POPs) and mercury, as well as explored whether and how the precautionary principle has been applied in European chemicals management. We have also analyzed policy options for global agreements on toxics and heavy metals. 

For more information:

H. Selin and N.E. Selin. 2008. “Indigenous Peoples in International Environmental Cooperation: Arctic Management of Toxic Substances.” Review of European Community and International Environmental Law, 17(1):72-83, doi:10.1111/j.1467-9388.2008.00589.x. [pdf]

N.E. Selin and H. Selin. 2006. “Global Politics of Mercury Pollution: The Need for a Multi-Scale Approach.” Review of European Community and International Environmental Law 15(3):258-269. [pdf]

N.E. Selin. 2005. “Mercury Rising: Is Global Action Needed To Protect Human Health and the Environment?” Environment 47(1):22-35. [pdf]

N. Eckley and H. Selin. 2004. “All Talk, Little Action: Precaution and its Effects on European Chemicals Regulation. “ Journal of European Public Policy 11:1 February 2004, 78-105. [pdf]

H. Selin and N. Eckley. 2003. “Science, Politics, and Persistent Organic Pollutants: Scientific Assessments and their Role in International Environmental Negotiations.” International Environmental Agreements: Politics, Law and Economics 3(1)17-42. [pdf]

N. Eckley. 2002. “Dependable Dynamism: Lessons for Designing Scientific Assessment Processes in Consensus Negotiations.” Global Environmental Change 12:15-23.[pdf]

N. Eckley. 2001. “Traveling Toxics: The Science, Policy, and Management of Persistent Organic Pollutants.” Environment 43(7):24-36.[pdf]

B. D. Rodan, D. W. Pennington, N. Eckley, and R. S. Boethling. 1999. “Screening for Persistent Organic Pollutants: Techniques to Provide a Scientific Basis for POPs Criteria in International Negotiations.” Environmental Science and Technology 33: 3482-3488. [pdf]

People: Noelle Selin, Leah Stokes, Ellen Czaika, Carey Friedman