Computational Toxicology in EPAs Office of Research and Development

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STAR Mercury Program
William G. Stelz, Presenter, Acting Hg MYP Lead
Author Board of Scientific Counselors February
23, 2005
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HG MYP RecapFrom Jan 19, 2005 Conf Call
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Overview (The Big Picture)

• Mercury MYP supports Agency Strategic Plan
  Multimedia/Healthy Communities and Ecosystems
  (Goal 4 )
• MYP Research efforts guided by the Mercury
  Research Strategy published in September 2000
• Strategy focused on reducing uncertainties
  associated with assessing and managing mercury
  risks
• http//cfpub.epa.gov/ncea/cfm/recordisplay.cfm?dei
  d20853

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Overview of Mercury Problem

• The Problem
• Mercury is present in environmental media at
  concentrations of concern
• to human and ecological health
• Mercury in environment has increased 2-5 times
  that of pre- industrial levels
• Exposure pathway of greatest concern to human
  health is that of fish consumption
• Mercury ranks first among pollutants causing
  U.S. fish advisories with 1900 fish advisories
  issued in 1999 alone number of advisories is
  increasing
• National consumption advisories have been
  issued by EPA/FDA providing nutritional
  information.

• ORD Response to Problem
• ORD research focusing on providing information to
  assess and manage mercury and methylmercury
  risks. Major research themes include
• Identify and quantify mercury sources
• Evaluate effective mercury control strategies
• Understand and model how mercury moves from
  sources to ecological and human receptors
• Assess risks to ecological resources and human
  health
• Mercury Sources
• Mercury in U.S. originates from global,
  regional and local sources
• EPA estimates about half of U.S. Hg deposition
  is from domestic man-made sources and about
  half is from global sources however, this
  estimate is very uncertain.
• Point sources dominate U.S. mercury emissions
• Combustion sources responsible for most mercury
  from point sources Another one of the
  significant contributors to mercury in the
  environment is mining.

• Mercury Behavior and Transport (cont)
• Everglades modeling
• Mercury Effects
• Human Health Effects
• Human health concern focuses on exposure to
  methylmercury, which is a developmental
  neurotoxin
• EPA established reference dose supported by NRC
  report (NRC 2000)
• EPA has done some exploratory analysis to
  quantify adult cardiovascular effects associated
  with methylmercury exposures.
• Ongoing research focuses on understanding
  neurotoxicity mechanisms and delayed responses
  from mercury exposure during development

• Mercury Sources (cont)
• Utility boilers are the largest
  combustion source of mercury
• Risk management efforts currently focus on
  evaluating effective control strategies for
  combustion sources
• Mercury Behavior and Transport
• Atmospheric deposition is the source of
  most environmentally available mercury
• Mercury deposition measured to
  assess relative importance of
  local vs. global sources
• Mount Bachelor (Oregon), Cheeka Peak
  (Washington) monitoring used to a ssess
  Asian mercury sources

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FOCUS OF MERCURY MYP RESEARCH

• Principal Components
• Sources
• Control technologies
• Environmental fate and behavior
• Ecological/Biological effects
• Cross-Component Activities
• Measuring
• Modeling
• Monitoring

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MYP Development

• Agency Strategic Direction
• GPRA goals/objectives/outcomes
• Program/Regional science needs

Develop key science questions to be addressed by
research

• Develop long-term goals (LTGs)
• Identify time-frame to deliver work
• Determine ORD role and role of others

• Determine annual performance goals to reach LTGs
• Identify sequence to provide results
• Integrate research from all sources

• Develop annual performance measures
• Determine who will accomplish work (in-house lab
  or center or STAR research)
• Ensure work can be done with available resources

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Logic Model Communicating How Environmental
Research Contributes to Outcomes

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Environmental Indicators
Outreach and Effective Transfer
Success will be measured by attainment of the
Clean Air Act requirements, as well as an
assessment of the magnitude of U.S. mercury
emissions by source, the health and environmental
effects of the emissions, and the cost and
availability of control technologies.
We communicate our work through peer-review
journal articles and summary reports that
formally document results transfer models,
methods, and data through workshops and
collaborative activities transfer knowledge,
data, and tools to clients and receive feedback
of client needs through workgroups and teams and
provide data to the public, the scientific and
regulated community, and to our clients through
state of the art use of the World Wide Web.
Short-Term Outcomes
Intermediate Outcomes
Resources
Research Activities
Outputs
Clients
Long-Term Outcomes
We apply our peoples expertise in health,
exposure, atmospheric/ engineering sciences with
use of our in house research facilities to expand
the state of these sciences, in combination with
extramural grants and partnerships..
.. to identify all important sources of mercury
to the atmosphere, and the physical/chemical
forms of Hg emitted, including the development
of improved models of the fate/transport of
mercury in the atmosphere and aquatic/
terrestrial systems..
to understand the processes leading to mercury
deposition from the atmosphere, develop models
capable of resolving source-receptor
relationships , promote the development of risk
management strategies based on sound science.. .
to obtain the knowledge needed by environmental
decision makers to regulate, along with the
development of technical information and data on
the performance of options to reduce emissions
from utility boilers.
.. to explore the effects, exposure, formation,
transport, measurement and control of
Hg/speciation of Hg ,in order to link results
from academic, industrial, and governmental
research..
.. transferring to OAR, OPPT, OW, OSW, OIA,
Regions, States, local organizations, electric
utilities, ORD, and the scientific and technical
communities..
resulting in improved human and ecosystem health.
LOGIC DIAGRAM FOR MERCURY RESEARCH
PROGRAM DESIGN
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Particulate Matter
Air Toxics
Global Change
Mercury
Pollution Prevention
Human Health
Contaminated Sites
Water Quality
Ecosystem Protection
Mercury MYP influences other MYPs
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KEY SCIENCE QUESTIONS

• How much methylmercury in fish consumed by the
  U.S. population is contributed by U.S. emissions
  relative to other sources of mercury (such as
  natural sources, emissions from sources in other
  countries, and re-emissions from the global
  pool) how much and over what time period, will
  levels of methylmercury in fish in the U.S.
  decrease due to reductions in environmental
  releases from U.S. sources?
• How much can mercury emissions from coal-fired
  utility boilers and other combustion systems be
  reduced with innovative mercury control
  technologies what is the relative performance
  and cost of these new approaches compared to
  currently available technologies?
• What is the magnitude of contributions of mercury
  releases from non-combustion sources how can the
  most significant releases be minimized?
• What are the risks associated with methylmercury
  exposure to wildlife species and other
  significant ecological receptors?

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KEY SCIENCE QUESTIONS CONTINUED

• What critical changes in human health are
  associated with exposure to environmental sources
  of methyl mercury in the most susceptible human
  sub-population? How much methylmercury are
  humans exposed to, particularly women of
  child-bearing age and children among
  highly-exposed population groups what is the
  magnitude of uncertainty and variability of
  mercury and methylmercury toxicokinetics in
  children?
• What are the most effective means for informing
  susceptible populations of the health risks posed
  by mercury and methylmercury contamination of
  fish and seafood?

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COLLABORATION AND PARTNERSHIP

• ORDs Mercury research efforts are coordinated
  with Program, Regional offices, and States
• OAR, OW, OSWER, OIA (International Affairs),
  OPPTS
• EPA Mercury Roadmap
• EPA Hg research is coordinated with other federal
  agencies
• NIEHS, DOE, USGS, (EPA/USGS Roundtable) , DOD,
  NOAA..

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STAR Mercury Program
CH3Hg
CH3Hg
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MERCURY MYP SNAPSHOT

• There are two LTGs defined in the MYP original
  had one.
• To reduce and prevent the release of mercury
  into the environment. (LTG 1)
• To understand the transport and fate of mercury
  from release to the receptor and its effects on
  the receptor. (LTG 2)
• There are 12 APGs defined in the MYP 5 in LTG 1
  and 7 in LTG 2
• Integrates ORD intramural and extramural research
  efforts through FY2010.
• Resources approximately 5.5M and 8.0 FTE per
  year.
• NCER RFAs address both LTGs and 6 different APGs.
• NCER Hg Research supports
• OAR,OW, OPPTS,OSWER
• Agency Strategic Plan Goal 4 Healthy Communities
  and Ecosystems

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Relationships Between APGs for Long Term Goal 1
Support development of regulations on mercury
emissions from coal-fired utility boilers by
producing data on measurement methods and control
technology performance, cost and residues that
can be readily used by OAR, OSW, States, Regions,
and industry to make informed choices on reducing
mercury risks in a cost-effective manner
FY03
FY04
Provide information on managing mercury and other
co-pollutants from utility boilers to support air
quality officials and utilities in determining
the most cost-effective approaches to reduce
emissions
FY05
FY06
Provide information and data to support
regulations from non-combustion sources of mercury
FY07
Support development of regulations on
multi-pollutant controls for coal-fired utility
boilers by producing data on measurement methods
and control technology performance, cost, and
residues that can be readily used by OAR, OSW,
States, Regions and industry to make informed
choices on reducing risks in a cost-effective
manner.
FY08
FY09
Provide information and data to support guidance,
regulations and policies for the management of
non-utility sources of mercury contamination,
including Hg stockpiles, hazardous wastes and
selected air and water sources.
FY10
Mercury Long-Term Goal 1 To reduce and prevent
the release of mercury into the environment
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Relationships Between APGs for Long Term Goal 2
FY03
Provide an assessment of key fate and transport
issues for tracing the fate of mercury from
sources to concentrations in fish tissue.
FY04
FY05
Develop a model for tracing mercury from
deposition to concentrations in fish tissues.
FY06
FY07
Develop information on sources of mercury
emissions and the local, regional, and global
atmospheric fate and transport of such emissions
Provide risk communication methods and tools for
mercury
FY08
Assess the risks of mercury exposures to
ecological receptors
FY09
Assess the health risks of mercury exposure to
humans
FY10
Produce an integrated multimedia modeling
framework for understanding mercury fate from
source to fish concentrations
Mercury Long-Term Goal 2 To understand the
transport and fate of mercury from release to the
receptor and its effects on the receptor
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Mercury RFAs
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STAR 1999 Hg Solicitation

• Research focused on Hg transport in a watershed
  context
• Objectives and Priorities
• To increase our ability to trace mercury from
  its entrance into the ecosystem through its
  biogeochemical cycling to the concentration of
  methylmercury in fish tissue.
• To promote the development of risk management
  strategies based on sound science.
• Key Science Questions
• For a given amount of mercury transported into a
  watershed, what is the predicted concentration of
  methylmercury in fish? How do mercury and
  methylmercury spatially distribute across the
  terrestrial and aquatic components of a
  watershed?
• What environmental and biochemical variables
  control transformation of mercury to
  methylmercury?
• Nine grants awarded (Total dollars approx. 7M
  )

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STAR 1999 Hg GRANTS

• PROJECTS ADDRESS
• What is the role of sulfur, especially in the
  form of sulfide, in mercury methylation and
  methylmercury fate and transport in watersheds?
  How much does methylmercury in ecosystems change
  in response to a change in mercury loading?
• What are the relative importances of atmospheric,
  in-lake and wetland sources of methylmercury, and
  the role of watersheds in controlling sources,
  transport, fate and bioavailability of Hg in a
  northern temperate lake system?
• What are the patterns of transport and
  transformations of mercury species in an upland
  northern hardwood forest through adjacent
  wetlands to the aquatic environment? And what are
  the processes and mechanisms controlling
  methylmercury concentrations and transport in
  porewater and surface water in wetlands?
• How can we best understand the physical and
  chemical processes that control the speciation
  and distribution of Hg in mine wastes and its
  release from mine sites?
• What are the reactions and processes controlling
  Hg emissions, cycling and bioavailability in Long
  Island Sound and its watershed/coastal water
  interface?
• What are the parameters that control the flux of
  elemental mercury from natural waters to the
  atmosphere?
• http//cfpub.epa.gov/ncer_abstracts/index.cfm/fuse
  action/recipients.display/rfa_id/109

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STAR 2001 Hg Solicitation

• Research focused on Hg emission sources,
  atmospheric processes, and deposition
• Objectives and Priorities
• To better understand natural and anthropogenic
  emissions of mercury to air, and the atmospheric
  processes that affect the transport,
  transformation and deposition of those emissions.
  
• To develop improved models of the emission,
  transport, transformation, and fate of mercury in
  the atmosphere to estimate response to emission
  reductions.
• Key Science Questions
• What fraction of the atmospheric mercury
  depositing to sensitive ecosystems in the
  U.S. is emitted from anthropogenic sources within
  the United States?
• What sources and/or source categories are most
  responsible for the atmospheric mercury
  depositing to sensitive ecosystems? What decrease
  in atmospheric mercury deposition can be expected
  from emission controls on various segments of
  domestic industry?
• Seven grants awarded (Total dollars approx.
  5.7M)

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STAR 2001 Hg GRANTS

• PROJECTS ADDRESS
• Scale and historical records of atmospheric
  mercury deposition related to human activities
  during the past 150 years.
• Understanding whether chemical reactions in the
  Arctic and upper levels of the atmospheric cause
  changes in the composition of mercury. Also try
  to determine whether mercury from other
  countries, particularly those in Asia, is being
  deposited in the U.S.
• Using mercury isotopes as a new way to
  investigate the natural and manmade emissions of
  mercury into the atmosphere. Isotopes will also
  be used to study the atmospheric processes that
  affect the transportation and deposition of
  mercury.
• Developing a model to determine the impact of
  local emissions, transport, soil emissions and
  sunlight on the deposition of mercury also
  Scientists will develop a database of Hg
  emissions from natural sources, including
  vegetation and wildfires.
• Developing a better understanding of the physical
  and chemical changes that occur to mercury in the
  atmosphere and the impacts of natural and manmade
  mercury sources on the areas where it is
  deposited and how mercury moves in ecosystems.
• http//cfpub.epa.gov/ncer_abstracts/index.cfm/fuse
  action/recipients.display/rfa_id/297

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Major NCER Research Activities

• FY 04/05
• APG - Provide an assessment of key fate and
  transport issues for tracking the fate of mercury
  from sources to concentrations in fish tissue.
• FY 06-10
• APG- Assess the risks of mercury exposures to
  ecological receptors
• APG - Provide information and data to support
  regulations from non-combustion sources of
  mercury
• APG- Develop information on sources of mercury
  emissions including the regional/global
  atmospheric fate and transport of such emissions.
• APG- Produce an integrated multimedia modeling
  framework for understanding mercury fate from
  source to fish concentrations.
• Major Clients OAR, OW,OPPTS,OIA, OSWER,
  Regions,States,
• ORD- NCEA, NERL,NRMRL Other Fed Agencies,
  Utilitiesetc.

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STAR RESEARCH ACCOMPLISHMENTS

• Investigators at The University of Maryland and
  the Academy of Natural Sciences developed new
  analytical tools in order to examine differences
  in Hg bioavailability for methylation through
  time and space in ecosystems. This helps to
  differentiate between Hg newly deposited to
  ecosystems separately from older pools of Hg in
  sediments and soils.
• STAR scientists at the Universities of
  Wisconsin/Madison and the University of Minnesota
  - are studying the factors that influence mercury
  levels in water and aquatic life, especially fish
  and have have shown that mixing zones, the areas
  where different types of waterbodies come
  together, provide significant pathways for
  methylmercury to enter the Lake Superior food
  web.
• STAR researchers at the University of Connecticut
  - conducted some of the only research on the
  behavior and fate of mercury in the marine
  environment. Their work in coastal waters, such
  as Long Island Sound, confirmed the prominent
  role of mercury production and emissions in
  marine systems. They also demonstrated how
  careful documentation of Hg in coastal waters
  such as Long Island Sound can be an indicator as
  to the status and trends of Hg pollution in these
  complex environments.
• Investigators at the University of North Dakota
  (Center for Air Toxic Metals) have developed
  real-time monitoring for elemental mercury
  emissions and a better understanding of in situ
  mercury flux and substrate speciation and have
  investigated the fate of captured trace metals to
  evaluate the usefulness of wet scrubber
  technology as a long-term viable solution for
  mercury control.

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NERL RESEARCH ACCOMPLISHMENTS

• Community Multi-scale Air Quality Model (CMAQ)
  simulates atmospheric processes using a
  3-dimensional grid approach to model complex
  interactions between the pollutants within each
  grid. NERL has modified the standard CMAQ model
  to simulate atmospheric mercury interactions in
  air and cloud water.
• Everglades Mercury Cycling Model (E-MCM) was
  developed by NERL to describe the
  interrelationships between atmospheric mercury
  deposition and observed mercury distribution in
  water, marsh soil and biota. The E-MCM was linked
  to the Everglades Phosphorus and Hydrology (EPH)
  model, to relate the effects of changing
  phosphorus dynamics on mercury cycling in the
  Everglades. This linked modeling system is
  expected to describe mercury fate more
  realistically than earlier model approaches.
• Watershed Mercury Simulation Software for TMDL
  Assessments a mercury watershed simulation
  technology developed and demonstrated to
  investigate proposed remediation and load
  reduction options. The approach links scientific
  knowledge of hydrology, sediment transport, and
  mercury cycling with recently developed GIS
  watershed software and databases. The resulting
  Grid-Based Mercury Model simulates flow, sediment
  transport, and mercury dynamics on a daily
  time-step across a diverse landscape.
• Impacts of Atmospheric Deposition and Lake and
  Watershed Processes on Mercury Exposures of Fish
  and Piscivorous Wildlife in New England Lakes
  Concentrations of total mercury and
  methylmercury in waters and sediments were
  characterized for a representative set of lakes
  in Vermont and New Hampshire, and compared with
  mercury accumulation in fish tissue and common
  loons from those water bodies. This screening
  tool can evaluate water loading standards against
  fish tissue levels, and to identify lakes in need
  of additional fish tissue sampling.

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STAR Mercury Accomplishments cont

• EPAs Small Business Innovation Research (SBIR)
  Program
• EPA SBIR Phase I and Phase II
• Brominated B-PAC Carbon Sorbent
• Manufacture of New Low-Cost High-Temperature
  Mercury Sorbent for Duct Injection at Electric
  Utilities
• Sorbent Technologies Corporation, Twinsburg, OH,
  Sid Nelson Jr, President Snelsonjr_at_SorbentTechnolo
  gies.com [phone]
• http//www.epa.gov/ncer/sbir

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Mercury Communications

• First RFA 1999 (Focus on Fate and Transport
  thru Watersheds)
• Latest RFA 2001 (Focus on atmospheric chemistry
  fate and transport)
• STAR Report on Mercury 10/2000
• STAR Mercury Progress Reviews FY 99 Grants
• Joint with NRMRL Workshop
• Joint with at ACS/Div of Envir Chem Mtg
• Final STAR Progress Review - (Nov 21, 2003 in DC)
  
• Synthesis Document for First RFA 1999 -Focus on
  Fate and Transport thru Watersheds. (Near
  Completion).
• First STAR Progress review for FY 2001
  (September, 2005)
• Other Activities
• Mercury Roadmap
• BOSC currently reviewing Hg MYP
• Next RFA Topic To Be Determined?

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Summary

• FUTURE RESEARCH DIRECTIONS (NCER)
• How do we strike a balance between ecological and
  health effects research?
• Linking the different pieces and disciplines to
  form better models.
• Further research on the source of methylmercury
  in top predators in the pelagic marine food
  chain.
• Isolating the microbial populations (specific
  strains of bacteria) in different ecosystems that
  are responsible for Hg(II) methylation. More on
  the actual mechanism of methylation.
• Uncertainties on the atmospheric fate and
  transport side related to reactions in the
  atmosphere that result in the oxidation of
  elemental mercury to form RGM. FY2001 grants
  will shed some light on this as well.