Yong Cai Department of Chemistry & Biochemistry and Southeast Environmental Research Center

1. Ave Maria University January 25, 2010 Mercury in the Florida Everglades Yong CaiDepartment of Chemistry & Biochemistry and Southeast Environmental Research Center Florida International UniversityMiami, FL

2. Research Team Florida International University Cai Group (Guangliang Liu, Damaris Hernandez, Yuxiang Mao, Sandra Zapata, Julio Cabrera) J. Richards, Len Scinto, Joel Trexler, T. Philippi, Evelyn Gaiser SERC Lab (Joseph Boyer) Many others US EPA Region 4 Pete Kalla Charles Appleby Daniel Scheidt K. Thornton Field sampling team and lab support personnel University of Georgia M. Madden

3. The Everglades Background • One of the largest freshwater marshes in the world • The masrch is a unique mosaic of sawgrass, wet prairries, sloughs, and tree islands. • Became a troubled system during last century • Central and Southern Florida Flood Control Project (created in 1948 by Fed. legislation) • Population increase (500K in 1950s, ~2 millions in 2000) • Today, 50% of historic Everglades wetland have been drained.

4. Background The Everglades

5. Background The Comprehensive Everglades Restoration Plan (CERP) The Restudy:Central & Southern Florida Project The Comprehensive Everglades Restoration Plan provides a framework and guide to restore, protect, and preserve the water resources of central and southern Florida, including the Everglades

6. Background The Comprehensive Everglades Restoration Plan (CERP) • The world's largest ecosystem restoration effort and includes more than 60 major components. • Because the region's environment and economy are integrally linked, the Plan provides important economic benefits. • Will result in a sustainable south Florida by restoring the ecosystem, ensuring clean and reliable water supplies, and providing flood protection. # Cost $11 billion in 30 years to implement

7. Background The Everglades Ecosystem Assessment Program (The program) Goal Provide timely ecological information that contributes to the environmental management decision on Everglades protection and restoration

8. The Everglades Ecosystem Assessment Program (The program) Background More specifically, the program contributes to Everglades phosphorus and mercury control effort and CERP by • Quantifying pre-restoration conditions in the marsh during 1995, as well as conditions subsequent to the initiation of restoration later in 1990s; • Assessing the effects and relative potential risk of multiple environmental stressors on the Everglades ecosystem, such as water management, soil loss, water quality degradation, and nutrient enrichment, habitat loss, and mercury contamination; • Permitting spatial analyses and identifying associations that provide insight into relationships among environmental stressors and observed ecological responses • …….

9. The Everglades Ecosystem Assessment Program (The program) Background A Unique program that combines several key aspects of scientific study, • Probably-based sampling design, which permits quantitative statements across space about ecosystem conditions; • Multi-media scope; • Extensive spatial coverage Program History USEPA and FIU began this program in 1993 Three phases have been completed (Phase I: 1993-1995; Phase II: 1999; Phase III: 2005)

10. Where Hg comes from Area source: 3.4 ton/yr Combustion: 137 ton/yr Oil Coal Natural Gas Municipal waste Miscellaneous: 1.4 ton/yr Manufacturing: 15.6 ton/yr

11. http://www.ec.gc.ca/MERCURY/EH/EN/eh-b.cfm#MM

13. Mercury and Human Health • One in six U.S. women of reproductive age might have mercury levels in their body that could put their babies at risk • More than 600,000 infants are born each year with blood mercury levels that might cause heart damage and irreversible impairment to brain function in children • Lower IQ levels resulting from mercury exposure in utero is estimated to cost the U.S. economy $8.7 billion a year in lost earning potential

14. Mercury and Human Health • Humans risk ingesting dangerous levels of mercury by eating contaminated fish. • Once in the human body, mercury acts as a neurotoxin, interfering with the brain and nervous system. • In adults, mercury poisoning can adversely affect fertility and blood pressure regulation and can cause • memory loss • Tremors • vision loss • numbness of the fingers and toes • heart disease • Exposure to mercury can be particularly hazardous for pregnant women and small children. Mercury exposure can cause • mental retardation • cerebral palsy • deafness and blindness • delaying walking and talking • learning disabilities

15. http://www.ec.gc.ca/MERCURY/EH/EN/eh-b.cfm#MM

16. Mercury in Fish • Once mercury enters a waterway, naturally occurring bacteria convert it to methyl mercury. • Methyl mercury then works its way up the food chain as large fish consume contaminated smaller fish. • Instead of dissolving or breaking down, methyl mercury accumulates at ever-increasing levels. • Predatory fish can have mercury concentrations in their bodies that are 10,000 times higher than those of their surrounding habitat.

17. Fish Consumption Advisory

18. Fish consumption advisories apply to over 2 million acres of water in South Florida.

19. The Everglades Ecosystem Assessment Program (The program) Background Biogeochemical Media Studied • Surface water • Floc (flocculent material found at surface-water interface • Porewater • Soil • Periphyton • Mosquitofish

20. Total Hg and MeHg in the Everglades

21. Mercury Cycling in the Florida Everglades

22. Fate of Mercury in the Florida Everglades

24. Objectives • To estimate mercury mass budget • To investigate major biogeochemical processes and controls that are pertinent to Hg distribution and cycling

25. Mass budget of Hg seasonally deposited into the Everglades: Assumptions • the seasonally deposited Hg will be redistributed into each compartment through a series of compartmentalization processes after deposition • the entering of seasonally deposited Hg into each compartment will result in an increase in Hg concentration of that compartment (denoted as ΔC in the equations) • the redistribution of newly deposited Hg across ecosystem compartments will follow the same patterns in which the legacy Hg is present

26. Mass budget of Hg seasonally deposited into the Everglades The left-hand side (LHS) is total Hg deposited during the whole dry (or wet) season while the right-hand side (RHS) represents THg amounts redistributed into each compartment plus outflow and evasion. The distribution ratio (R) of Hg between water and other compartments (R = [Hg in solid or biological matrix] / [Hg in water], L/g) was defined and used to relate water Hg to Hg in the other compartments. Liu et al., ES&T, 2008, 42,1954

27. Input Parameters Liu et al., ES&T, 2008, 42,1954

28. Liu et al., ES&T, 2008, 42,1954

29. After R was calculated for the dry and wet season from the data obtained during the 2005 sampling events and the median R was introduced in above Equation, ΔCfor surface water was obtained first and then ΔC for the other compartments were calculated. For MeHg, a similar mass balance was calculated. Liu et al., ES&T, 2008, 42,1954

30. Mass (in bold, kg) and fraction estimates of THg deposited to the Everglades in (A) dry and (B) wet season in 2005. Rectangle size shows seasonal variation in compartment mass

31. Mass (in bold, kg) and fraction estimates of THg deposited to the Everglades in (A) dry and (B) wet season in 2005. Rectangle size shows seasonal variation in compartment mass

32. Mass (in bold, g) and fraction estimates of MeHg produced (from seasonally deposited Hg) in the Everglades during (A) dry and (B) wet season in 2005. Rectangle size shows seasonal variation in compartment mass. MeHg produced is shown in a rectangle with dashed line, with filled callouts linked to respective matrices. MeHg retained in soil, floc, or periphyton after redistribution is shown by line callouts.

33. Mass (in bold, g) and fraction estimates of MeHg produced (from seasonally deposited Hg) in the Everglades during (A) dry and (B) wet season in 2005. Rectangle size shows seasonal variation in compartment mass. MeHg produced is shown in a rectangle with dashed line, with filled callouts linked to respective matrices. MeHg retained in soil, floc, or periphyton after redistribution is shown by line callouts.

34. Fate of Mercury Deposited into the Florida Everglades during the 2005 Wet Season Liu et al., ES&T, 2008, 42,1954

35. Summary • Compared with dry season, wet season is more favorable for Hg bioaccumulation, indicated by higher mosquitofish THg, bioaccumulation factor (BAF), and biomagnification factor (BMF) from periphyton to mosquitofish. • Substantially elevated MeHg production in floc and periphyton and changes in food web structure in the wet season could play an important role in seasonality in Hg bioaccumulation. • Mercury mass budget in the Everglades was estimated.

37. Mosquitofish THg versus periphyton MeHg. Closed and open circles are data obtained in the dry and wet season, respectively.

38. Mosquitofish THg versus water MeHg. Closed and open circles are data obtained in the dry and wet season, respectively.

39. Mosquitofish THg versus DOC-normalized water MeHg. Closed and open circles are data obtained in the dry and wet season, respectively.

40. Bioaccumulation factor (BAF) as a function of DOC. Closed and open circles are data obtained in the dry and wet season, respectively.

41. Correlations between Hg (THg, MeHg, and MeHg/THg ratio) and DOC in Everglades water. Closed and open circles are data obtained in the dry and wet season, respectively. Indicating DOC has stronger binding capability with MeHg than with THg

42. MeHg/THg ratios in water reported in literatures. The numbers in parentheses are the median values. a: calculated from data reported in the original literature.

43. Implication for Hg Bioaccumulation • Relatively high concentration of MeHg in water, floc, and periphyton • Periphyton is an important base component of the Everglades food web (a primary food source for numerous species of invertebrates, small fish, and amphibians) • Floc layer could contribute to Hg bioaccumulation by increasing MeHg production and mobility of THg and MeHg • High MeHg/THg ratios in water

44. Acknowledgements • EPA Office of Research and Development • US EPA Region 4 • Army Corps of Engineers • National Park Services • Florida Department of Environmental Protection • Mercury Laboratory (SERCMLAB) at FIU • Battelle Marine Science Laboratory

45. FLORIDA INTERNATIONAL UNIVERSITY Miami's public research university • One of America's most dynamic institutions of higher learning • Among the top 100 public national universities (U.S. News & world report) • One of the top 10 public commuter universities (money) • The country's 18th best value in public higher education (Kiplinger's personal finance magazine) • A member of the Phi Beta Kappa, the nation's oldest and most distinguished academic honor society • The advancement of teaching as a doctoral/research university-extensive, the highest ranking in its classification system (Carnegie foundation)

46. 27 faculty and 8 staff personnel • Our faculty receive outside funding that includes support for graduate and undergraduate research assistants • Our students regularly contribute to research publications in top scientific journals • State-of-the-art instrumentation • Initiated a PhD program in 1997 and currently have a variety of undergraduate and graduate degree programs • Our students also benefit from several institutes and centers: • The Southeast Environmental Research Center (SERC) • The International Forensic Science Institute (IFRI) • The Advanced Mass Spectrometry Facility (AMSF), • The Center for the Study of Matter at Extreme Conditions (CeSMEC)

47. FIU Chemistry Program • The Department of Chemistry and Biochemistry faculty offers a broad range of expertise in the areas of • Analytical • Biochemistry • Environmental chemistry, • Forensic chemistry, • Natural (organic) products chemistry, • Inorganic chemistry, and • Physical chemistry. • At the graduate level, we offer a MS and a PhD in Chemistry. Interdisciplinary MS degree in Forensic Science and PhD in Chemistry with Forensic track are also offered.

48. Graduate Study in Chemistry • Master of Science (M. Sc.) • The Master of Science in the Department of Chemistry is a research-intensive degree and the M.S. program provides flexibility for students with varied interests. • Graduates of our M.S. program are well prepared for technical jobs in the chemical industry, teaching, doctoral programs, and professional schools. We accept part-time and full-time students into the M.S. program. • The Master of Science in Forensic Science • The Master of Science in Forensic Science is an interdisciplinary program designed to prepare students for careers in forensic science laboratories. The program may also be suitable preparation for doctoral instruction in several disciplines.

49. Doctor of Philosophy (Ph.D.) • The Doctoral program is a research-intensive degree emphasizing critical thinking and original problem solving. • While the department’s strength is the interdisciplinary nature of the faculty research, particularly in the areas of environmental and biomedicinal chemistry, research projects in traditional areas of chemistry are also available to the students. • The student typical chooses a series courses, which is focused in one of chemistry sub-disciplines, analytical, biochemistry, inorganic, organic or physical.

50. Financial Assistance • Financial aid comes from various agencies (federal, state and local governments, universities, community organizations, and private corporations or individuals) to help students meet the cost of attending college. • Most of our graduate students are financially supported, with full tuition scholarships and assistantships. The current annual assistantship stipend is at least $22,660 for PhD and $15,000 for MS. Health insurance is subsidized (75%) by FIU. Dissertation Year Fellowships, Presidential Enhanced Assistantships, and Presidential Fellowships are also available on a competitive basis to excellent students. • Financial Assistance for Minorities Students • 1. Graduate Minority Opportunities Program • 2. McKnight Doctoral Fellowship Program • 3. Delores Auzenne Fellowship