Docstoc

Slide 1 - Florida International University

Document Sample
Slide 1 - Florida International University Powered By Docstoc
					                                      Ave Maria University
                                      January 25, 2010




   Mercury in the Florida Everglades




                Yong Cai

Department of Chemistry & Biochemistry and
 Southeast Environmental Research Center
      Florida International University
                 Miami, FL
              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
                                                      2
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.
                                                 3
                 Background
The Everglades




                         4
                                       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


                                                  5
                                              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

                                                          6
                                      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




                                                7
    The Everglades Ecosystem                              Background
Assessment Program (The program)


        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
   …….


                                                                             8
    The Everglades Ecosystem                          Background
Assessment Program (The program)



                 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)

                                                                   9
                  Where Hg comes from

                                            Area source: 3.4 ton/yr




                   Combustion: 137 ton/yr
Oil
Coal                                         Miscellaneous: 1.4 ton/yr
Natural Gas
Municipal waste
                                            Manufacturing: 15.6 ton/yr




                                                                 10
http://www.ec.gc.ca/MERCURY/EH/EN/eh-b.cfm#MM   11
12
    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

                                               13
        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


                                                                            14
http://www.ec.gc.ca/MERCURY/EH/EN/eh-b.cfm#MM   15
           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.

                                                16
Fish Consumption Advisory




                            17
Fish consumption
advisories apply to
over 2 million
acres of water in
South Florida.




                      18
    The Everglades Ecosystem                   Background
Assessment Program (The program)

                Biogeochemical Media Studied

                                                Surface water
                                                Floc (flocculent
                                                material found at
                                                surface-water
                                                interface
                                                Porewater
                                                Soil
                                                Periphyton
                                                Mosquitofish




                                                             19
Total Hg and MeHg in the Everglades




                                      20
Mercury Cycling in the Florida Everglades
                                            21
Fate of Mercury in the Florida Everglades

                                            22
23
            Objectives

 To estimate mercury mass budget


 To investigate major biogeochemical
 processes and controls that are
 pertinent to Hg distribution and cycling




                                        24
 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
                                               25
        Mass budget of Hg seasonally deposited into the
                         Everglades


M BD  C SW VSW  C SD M SD  C FC M FC  C PE M PE  C PK M PK  C FS M FS  C SW VOF  M EV  M BU
  THg     THg         THg          THg          THg          THg          THg          THg THg    THg    THg




    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
                                                                                                   26
Input Parameters




      Liu et al., ES&T, 2008, 42,1954
                                        27
Liu et al., ES&T, 2008, 42,1954
                                  28
C SW
   THg




M BD  C SW  (V SW  R SD M SD  R FC M FC  R PE M PE  R PK M PK  BAFFS M FS  VOF )  M EV  M BU
  THg     THg            THg         THg         THg         THg          THg                 THg    THg




         After R was calculated for the dry and wet season from the data
         obtained during the 2005 sampling events and the median R was
C SW
   THg

         introduced in above Equation, ΔC for surface water was obtained first
         and then ΔC for the other compartments were calculated.



         For MeHg, a similar mass balance was calculated.

M PD  C SW  (V SW  R SD M SD  R FC M FC  R PE M PE  R PK M PK  BAFFS M FS  VOF )  M BU
  MeHg    MeHg           MeHg        MeHg        MeHg        MeHg          MeHg               MeHg




                                                 Liu et al., ES&T, 2008, 42,1954
                                                                                                 29
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




                                                                    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, 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.




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




                                                                    35
36
                            1000




       Mosquitofish THg conc. (ng/g)
                                                                                     (b)


                                       100




                                        10

                                                                           R=0.465 (N=110)
                                                                           P<0.001

                                         1
                                             0.1              1                 10
                                                   Periphyton MeHg conc. (ng/g)

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




                                                                                             37
                               1000




        Mosquitofish THg conc. (ng/g)
                                                                               (a)

                                        100




                                         10
                                                                   R=0.183 (N=167)
                                                                   P>0.05

                                          1
                                           0.01    0.1               1               10

                                                  Water MeHg conc. (ng/L)


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




                                                                                          38
                                      1000




            Mosquitofish THg Conc. (ng/g)
                                                                                (c)

                                            100




                                             10
                                                                      R=0.579 (N=167)
                                                                      P<0.001

                                              1
                                                  0.01                          0.1
                                                    MeHg/DOC (ng/g)


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




                                                                                        39
                     6.5
                                          (d)        R = -0.639 (N=167)
                                                     P < 0.001
                     6.0

         Log (BAF)
                     5.5


                     5.0


                     4.5


                     4.0
                           0   10    20         30       40       50      60

                                    Water DOC conc. (mg/L)


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




                                                                               40
                                     10                                                                                                 10




                                                                                                 MeHg concentrations in water (ng/L)
THg concentrations in water (ng/L)

                                                  R = 0.524                                                                                       R = 0.511
                                                  P < 0.001                                                                                       P < 0.001


                                                                                                                                         1




                                                                                                                                        0.1
                                     1




                                          1                          10                    100                                         0.01
                                                                                                                                              1                     10                    100
                                                      DOC concentrations in water (mg/L)                                                             DOC concentrations in water (mg/L)


                                                                                                 Correlations between Hg (THg, MeHg,
                                     100                                                         and MeHg/THg ratio) and DOC in
                                                   R = 0.403
                                                   P < 0.001                                     Everglades water. Closed and open
MeHg/THg in water (%)




                                                                                                 circles are data obtained in the dry and
                                                                                                 wet season, respectively.
                                      10




                                          1
                                                                                                                                         Indicating DOC has stronger
                                              1                       10                   100                                           binding capability with MeHg than
                                                      DOC concentrations in water (mg/L)
                                                                                                                                         with THg
                                                                                                                                                                                                41
MeHg/THg ratios in water reported in literatures. The numbers in parentheses are
the median values.
Water type         Geographic location                       MeHg/THg ratio (%)   Reference
Wetland            Florida Everglades                        2-52 (11)            This study

Wetland            Florida Everglades                        4.4-14 (7.2)a        (Babiarz et al., 2001)

Wetland            New York                                  6-16                 (Driscoll et al., 1998)

Surface ocean                                                1-5                  (Morel et al., 1998)




River              New Jersey                                0.01-1.3 (0.2)a      (Schaefer et al., 2004)

River              Wisconsin                                 0.9-7.8 (4.4)a       (Babiarz et al., 1998)

Lakes              Remote                                    1-20                 (Morel et al., 1998)

Lakes              New Jersey                                2-34 (5)a            (Schaefer et al., 2004)

Lakes              Wisconsin                                 6-30 (5.8)a          (Watras et al., 1998)

Freshwaters        Michigan, Minnesota, Wisconsin, Georgia   0.4-36 (3.2)a        (Babiarz et al., 2001)

Estuarine waters   Florida Bay                               <0.03-52 (10)        (Kannan et al., 1998)


 a: calculated from data reported in the original literature.                                               42
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

                                                      43
      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

                                     44
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)
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)
                         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.
         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.
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.
        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
                      Affiliated Organizations




– SERC promotes, coordinates and conducts environmental research
  in the Southeastern United States and the Caribbean.
– SERC facilitates linkages between scientists, agency representatives
  and government agencies and provides an organizational structure for
  regional environmental research initiatives and interdisciplinary
  environmental investigations.
– SERC serves as the physical location for offices of two of the federal
  government’s efforts to restore the South Florida ecosystem. Both the
  United States Geological Survey - Biological Research Division
  (formerly the National Park Service Cooperative Parks Study Unit)
  and the South Florida Ecosystem Restoration Task Force are housed
  within SERC.
                       Affiliated Organizations




 The IFRI serves local and national law enforcement efforts in the
  application of scientific principles to the administration of justice.
 A large number of institute affiliated FIU faculty conduct research and
  provide forensic expertise. The Metro-Dade Police Department, the
  Dade County Medical Examiner's Office, the Broward Sherriff's Office,
  the Broward County Medical Examiner's Office and the Drug
  Enforcement Administration house local forensic laboratories in South
  Florida.
 A combined total of over 100 scientists work in these laboratories
  conducting evidence examinations and offering expert testimony in state
  and federal courts.
                   Affiliated Organizations

                     Graduate Student
                       Organization

 The Chemistry Graduate Student Organization was formed by the
  graduate students in the Department of Chemistry.
 The goal of the association is to promote awareness of our interests
  within the student government body, to increase interaction of
  students within the program, and become more active voice in
  issues that affect the growth of technical industries in this
  community.
 The association seeks to promote scholarship, community service,
  and events that increase the understanding and importance of
  chemistry and science in general.
                        Affiliated Organizations




 The Chemistry Club at FIU was recognized as a Chapter of the Student
  Affiliates of the American Chemical Society in October 1979.
 The chapter gives the opportunity for students of chemistry related
  sciences to become better acquainted with a myriad of subjects in the
  chemical profession and provides experience in preparing and
  presenting technical material.
 It also fosters the awareness of the responsibilities and challenges of the
  modern chemist.
 Moreover, academic as well as employment information concerning the
  field of chemistry are disseminated.
Available state-of-the-art instrumentations



    – The Department of Chemistry was recently awarded
      managerial and technical responsibility of the AMSF.
    – AMSF is a cutting edge university wide mass
      spectrometry facility for research and contract work.
    – The facility is envisaged to be used particularly heavily
      for funded research activities by faculty and students
      from the Department of Chemistry and Biochemistry as
      well as others within FIU.
             Available state-of-the-art instrumentations

 Foster and Freeman Glass Refractive Index Measurement System
    (GRIM)
   Varian GC/Ion Trap/MS-MS (2 available)
   Several GC/FID (Flame Ionization Detectors)
   Purge and Trap GC/NPD
   HP-6890 GC/MS with headspace, pyrolysis, and liquid sampling options.
    Negative/Positive mode
   HP-4500 Plus ICP-MS with a Cetac LSX-200 laser ablation system
   PE SCIEX ICP/MS DRC II
   LSX 200Plus LA Sample Introduction System
   LSX 500Plus LA Sample Introduction System
   GC/Atomic Emission Spectroscopy
   HPLC with Electrochemical Detector
              Available state-of-the-art instrumentations

   Capillary Electrophoresis
   Finnigan/Thermoquest HPLC-PDA-MS
   Bruker 400 and 600 MHz NMRs
   FT-IR Spectrometer
   Isco Supercritical Fluid Extractor (SFE)
   Pharmacia FPLC (2 available)
   Several HPLC/UV Detector
   Detector GE Ion Trak (IMS)
   Hitachi FMBIOII Gel Electrophoresis Analyzer
   PE Applied Biosystems 310 CE Genetic Analyzer
   Several Thermocyclers of various brands
   Intoxilyzer 5000 (CMI)
   Beckman P/ACE CE systems with various detectors
   Beckman MSQ CE system with UV and PDA detectors

				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:10
posted:3/24/2011
language:English
pages:57