vxEPA
United States
Environmental Protection
Agency
EPA/600/R-09/003 January 2009 www.epa.govJord
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A Conceptual Framework for
U.S. EPA's National Exposure
Research Laboratory
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Office of
Research and Development
National Exposure
Research Laboratory
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vvEPA
United States
Environmental Protection
Agency
EPA/60Q/R-QW003 January 2009 www.epa.gov/ord
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Notice
The information in this document has been funded by the United States
Environmental Protection Agency. It has been subjected to the Agency's
peer and administrative review and has been approved for publication as
an EPA document.
Abstract
The Conceptual Framework for the U.S. EPA's National Exposure Research
Laboratory (NERL) provides a foundation for addressing NERL's research
mission and its scientific leadership goals. The document defines the domain
of exposure science; describes the uses for exposure science within the EPA;
and provides the principles for developing and implementing NERL research.
NERL's mission is to conduct human health and ecological exposure research
that provides the pertinent databases, predictive models, and analytical tools
necessary for the EPA to carry out its mission. Fulfilling the EPA's mission to
protect human health and the environment carries with it the challenge of
understanding exposures for tens of thousands of chemical contaminants,
a wide range of biological stressors, and many physical stressors. Exposure
science provides the Agency with the fundamental knowledge and tools
necessary to assess potential exposures for emerging environmental threats
and to mitigate exposures to known contaminants and stressors.
The Conceptual Framework articulates the importance of exposure science
in both assessing and managing risks. Internally, the document creates
our identity as the National Exposure Research Laboratory and provides
a common understanding and a common language for exposure research
and its applications. The document also communicates NERL's mission;
organizational goals; and processes for strategic planning, communication
and organizational development. Externally, the document is intended to
define and advance the field of exposure science for both the EPA and the
broader scientific community.
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Letter from the Director
I am pleased to present this framework document. The goals for the
document are to provide a clear and concise conceptual framework for
exposure science and an outline for the role of exposure science at the
EPA. It also describes the principles for how we move forward as a national
laboratory committed to providing scientific understanding, knowledge,
and assessment tools that inform Agency policy decisions and aid in
implementing Agency regulatory programs.
As such, the concepts presented in this framework are the foundation for
NERL's future. This document is a product of considerable discussion and
input from across the laboratory. I would like to particularly acknowledge
Linda Sheldon and Rochelle Araujo the primary authors of the document
as well as NERL's division directors, who took a leadership role in
developing the framework. Additionally, I would like to thank the NERL
BOSC Subcommittee for their constructive comments, which have been
incorporated into the document.
NERL is uniquely positioned to address the Nation's most challenging
environmental exposure questions. I am confident that this framework will
serve us well as we move exposure science into the 21st century.
^M^
Lawrence W. Reiter, Ph.D.
Director, National Exposure Research Laboratory
Office of Research and Development
Research Triangle Park, North Carolina
iii
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Foreword
The exposure framework document was written with the goal of defining
the domain of exposure science, the uses for exposure science within the
EPA, and the principles for developing and implementing NERL research.
In creating this framework, the laboratory's Associate Directors and Division
Directors gathered to reflect, discuss, and define exposure science and their
vision for developing and maintaining a strategy-focused organization that
provides exposure science leadership at national and international levels.
We wish to thank the following individuals for their time spent crafting this
framework: Rochelle Araujo, Robert Dyer, Roy Fortmann, Florence Fulk, Fred
Hauchman, Daniel Heggem, S.T. Rao, Mark Rodgers, Linda Sheldon, and
Eric Weber.
IV
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Table of Contents
1.0 Introduction 1
2.0 Exposure Science 5
3.0 Exposure Science at U.S. EPA 15
3.1 Role of Exposure Science in the Risk Assessment/Risk Management Context 15
3.2 Role of Exposure in EPA Regulations 19
4.0 Exposure Research at NERL 25
4.1 Research Products: To have an impact, what must we deliver? 26
4.1.1 Develop!ng a Research Portfolio 27
4.1.2 Designinga Research Program 28
4.1.3 Communicating NERL's Research 29
4.2 Internal Business Processes: To succeed, how do we carry out our work? 30
4.2.1 Management Principies 30
4.2.2 M anagement Processes 31
4.3 Employee/Organization Capacity: To achieve our vision, what competencies
are needed? 32
4.3.1 Strategic Workforce Planning 32
4.3.2 Leadership Development within the Workforce 34
4.4 Financial Resources Management: To achieve our goals, how do we
efficiently allocate resources? 36
4.4.1 Financial Resilience 36
4.4.2 Optimization and Integration 36
References 39
Appendix A 41
Acronyms 42
List of Figures
Figure 2-1 Conceptual diagram of exposure 5
Figure 2-2 The highest concentrations and the most susceptible populations
create the greatest potential risk 6
Figure 2-3 Source-to-outcome framework for human health exposure research 8
Figure 2-4 Source-to-outcome framework for ecological exposure research 9
Figure 3-1 Framework for protecting human health and the environment 16
Figure 4-1 Aligning NERL's business as a Strategy-Focused Organization 25
Figure 4-2 Evaluation filters and criteria for assessing potential research areas 27
Figure 4-3 Scientific expertise for exposure research 33
Figure A-l Research planning in EPA 41
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!ihe challenges of environmental
. protection range from
understanding the potential
risk associated with exposure
of humans and ecosystems to a
newly manufactured chemical, to
minimizing human exposure to
pathogens at public beaches, to
linking human activities on the
landscape with physical alterations
of ecosystems.
In the United States, there are
more than 75,000 industrial
chemicals currently tracked
by the U.S. Environmental
Protection Agency (EPA), with an
estimated 2,200 new chemicals
manufactured or imported each
year. Since 2001, the list of
environmental chemicals reported
in the Centers for Disease Control
and Prevention's First, Second,
and Third National Report on
Human Exposure to Environmental
Chemicals has grown from 27 to
148 (NRC, 2006) evidence
of both the need and ability to
monitor the public for exposure
to contaminants of concern. The
popular media routinely reports
concerns about contaminants in
drinking water supplies, at public
beaches, and in the Nation's
surface waters. A June 2007
Newsweek article (Underwood,
2007) highlighted a growing
public awareness of potential
risks associated with "emerging
contaminants," including
Pharmaceuticals, cosmetics,
and antibacterial soaps. Cited
in the article was a 2002 survey
by the U.S. Geological Survey
which detected a number of
these compounds in 80 percent
of the 139 streams it examined
(Koplin, 2002). While each of the
compounds was generally present
in small quantities, findings like
these raise an overarching question:
"What happens when a person is
exposed to a whole cocktail of them
(Underwood, 2007)?"
Other contaminants are not
chemicals manufactured for
product use; rather they are
byproducts of modern society.
As an example, particulates in
air come from power plants,
automobile emissions, and
emissions from natural sources. In
addition, many other contaminants
can be formed when emissions
from biogenic and anthropogenic
sources interact in the
environment.
For ecosystems, environmental
protection goes beyond
minimizing exposures to chemical
contaminants and includes the
restoration and maintenance of the
physical and biological integrity
of ecosystems. Understanding the
relationships between land use,
such as urban development and
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agricultural activities, and how
these activities can physically alter
ecosystems is a critical component
of environmental protection. In the
EPA's 2006 report on the condition
of wadeable streams in the United
States, stream bed sediments
and river bank disturbance were
identified as two of the most
widespread stressors degrading
stream condition for fish and other
aquatic life. Both of these stressors
represent physical alteration of
stream systems and are typically
associated with human activity
alongside streams.
Fulfilling the EPA mission
to protect human health
and the environment carries
with it the challenge of
understanding exposures for
tens of thousands of chemical
contaminants, a wide range of
biological stressors, and many
physical stressors. The EPA's
National Exposure Research
Laboratory (NERD is uniquely
positioned to address the
Nation's most challenging
environmental exposure
questions. Exposure science
provides the Agency with
the fundamental knowledge
and tools necessary to assess
potential exposures and risks to
emerging environmental threats
and to mitigate exposures
to known contaminants and
stressors. NERL's combined
expertise in modeling, chemistry,
physics, meteorology, statistics,
computational science,
microbiology, ecology, molecular
biology, geographic information
systems, and remote sensing
enables the Laboratory to bring
cutting-edge research and
technology to the field of exposure
science.
NERL's mission is to conduct
human health and ecological
exposure research that provides the
pertinent databases and predictive
modeling and analytical tools
necessary for the EPA to carry
out its mission. NERL produces
research to reduce critical exposure
NERL's mission is
to conduct human
health and ecological
exposure research for
the EPA to carry out
its mission. NERL
produces research to
reduce critical exposure
uncertainties associated
with the Agencys policy
decisions and provides
international leadership
in exposure science.
uncertainties associated with the
Agency's policy decisions and
provides international leadership in
exposure science. This document
is a conceptual framework for
addressing NERL's research
mission and achieving its goal
of scientific leadership. In the
following sections, the document
* define the domain of exposure
science (Section 2.0);
* describe the uses for exposure
science within the EPA (Section
3.0); and
provide the principles for
developing and implementing
NERL research within the context
of the conceptual framework
(Section 4.0).
The primary audience for this
document is the NERL research
community. Internally, the
document creates our identity
as the National Exposure
Research Laboratory. It provides
a common understanding and a
common language for exposure
research and its applications.
As an internal resource, it also
communicates our mission,
our organizational goals, and
the processes for strategic
planning, communication, and
organizational development.
Externally, the document is
intended to define and advance
the field of exposure science
for both EPA and the broader
scientific community. Very
importantly, it articulates the
importance of exposure science
in both assessing and managing
risks. Finally, the document
communicates our mission and
our goals to our partners and
collaborators both within and
outside of EPA. <&
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understanding exposures for
tens of thousands of chemical
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2.0
Exposure is the contact of a
stressor with a receptor for a
specific duration of time (Zartarian,
et.al, 2005). A stressor is any
biological, physical, or chemical
agent that can potentially lead to
an adverse impact. This is a very
general concept and includes those
stressors that lead to exposure
through direct contact as well as
those stressors that act indirectly
through a series of environmental
processes. A receptor is a living
organism or group of organisms.
In human health research,
the individual or population of
individuals is the receptor. In
ecological research, the receptor
can be individual plants or animals,
communities of plants or animals,
or groups of communities organized
into an ecosystem.
For exposure to occur the stressor
and the receptor must intersect in
both space and time, as illustrated
in Figure 2-1 (below). Exposure
science characterizes and predicts
Distribution of
Stressors in Space
and Time
Exposure
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Distribution of
Receptors in Space
and Time ,
Figure 2-1. Conceptual diagram of
exposure
this intersection. This fundamental
definition is consistent with EPA's
Guidelines for Risk Assessment
(USEPA, 1992) and its Guidelines
for Ecological Risk Assessment
(USEPA, 1998).
Exposure is described in terms
of the magnitude, frequency,
and duration of contact. For
most stressors, the magnitude of
exposure to a receptor is a critical
characteristic in determining
adverse effects. Likewise, both
the frequency and the timing of
exposures can have an important
impact. Exposure can be either
continuous or intermittent
depending upon the source of
the stressor, its persistence in
the environment, and receptor
activities that lead to contact with
the stressor. Exposure durations
can range from short-term or acute
(i.e., minutes to hours) to long-
term or persistent (i.e., years). For
example, exposure to an accidental
chemical release would be short-
term and intermittent. While at
the other end of the spectrum,
chemicals such as lead, dioxins,
polychlorinated biphenyls (PCBs),
and organochlorine pesticides are
persistent in the environment and
can be found in environmental
media where humans and wildlife
have frequent contact. Because of
this, exposures to these chemicals
*,
-------
are generally continuous and
persistent. Additionally, for some
stressors, there are very specific
receptor life stages (such as fetal
development) where specific and
characteristic exposure routes may
predominate and where exposure
will lead to an enhanced adverse
outcome.
Exposure assessment is the process
for identifying potentially exposed
populations and pathways of
exposure, as well as quantifying the
magnitude, frequency, duration,
and time-pattern of exposure.
The adverse impact of exposure
depends upon the characteristics
of the exposure, the potency of the
stressor, and the susceptibility of
the receptor. The greatest adverse
impact of any given stressor will be
to those individuals, populations,
communities, or ecosystems that
are most exposed and/or most
susceptible to the exposure. This
concept is illustrated in Figure 2-2
(right), which expands upon the
simplified illustration in Figure 2-1.
Within the exposure research
framework, vulnerability refers
to characteristics of a receptor
(e.g., an individual, population or
ecosystem) that places them at
increased risk of an adverse effect
(USEPA, 2005). The text box above
shows some of the ways that a
receptor may be more vulnerable.
Included are factors that can
lead to increased susceptibility
or higher exposure. Susceptibility
refers to characteristics that lead
to a greater response for the
same exposure. The concepts
of differential exposure and
susceptibility are crucial given the
EPA's mandate to protect not only
the general population, but also
those populations at greatest risk.
Exposure assessments, therefore,
should identify and understand
those conditions that lead to
the highest stressor intensities
Vulnerability
(Exposure/Activity)
«> Age or life stage
»:» Culture and lifestyle
«> Activities and occupation
»:» Geographic locations/
distributions
«> Socioeconomic status
(Biological)
Age or life stage
Gender
Genetic differences
Health status
Previous exposures
and resulting exposures, as well
as those situations that lead to
exposure for the most susceptible
receptors.
Figure 2-2 suggests that both
stressors and receptors vary in
time and space; however, there is
an important distinction between
human and ecological exposure
research in this regard. The human
receptor is essentially the same
in all locations; only stressor
intensity, population characteristics
(e.g., density), and susceptibility
will vary in space. For ecological
exposures, location determines
not only the stressors present and
their intensities, but also which
receptors might be present, and the
circumstances under which they
encounter the stressor. That is, the
organisms that are present vary as
a function of location, as well.
Distribution of
Stressors in Environmental Media
Highest
Intensities
Greatest
Potential
Risk
Individual Activities and
Locations
Figure 2-2. The highest concentrations and the most susceptible
populations create the greatest potential risk.
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There are many commonalities
between human and ecological
exposure science and these
commonalities serve as the basis
for this framework document.
There are also differences that
must be recognized in order to
have a complete understanding
of the science. For example, our
understanding of the concepts of
human and ecological exposure
science is influenced by the EPA's
responsibilities in the two areas.
The EPA is responsible for human
health outcomes solely related to
environmental stressors (primarily
chemical or biological agents). In
contrast, the Agency is responsible
for protecting the condition or state
of entire ecosystems from multiple
stressors, including physical,
chemical, and biological agents.
Important differences between
the human health and ecological
disciplines are shown in the table
below.
The goal of exposure science is to
characterize, forecast, hindcast,
and manage exposures. In addition
to identifying and characterizing
stressors and receptors, exposure
research also characterizes and
links the processes that impact
the movement and interactions
of stressors from their sources
through the environment, and
their intersection with receptors.
This includes understanding and
describing the interactions of
multiple stressors, with diverse
environments, and multiple
receptors. In very simple terms, the
elements of exposure science can
be illustrated within a "source-to-
outcome" framework (Figures 2-3
and 2-4 on following pages), in
both forward and reverse directions,
providing the critical link between
sources of environmental stressors
and associated impacts.
Differences Between Human Health and Ecological Research Disciplines
Human Health Research
Agency is responsible for human health outcomes
solely related to environmental stressors
Chemical and biological agents are primary stressors
of concern
Single Receptor - human at individual or population
level
Receptors (humans) are the same at all locations -
population density, vulnerability, and susceptibility may
change across locations
Traditionally, risks have been evaluated for a single
stressor at a time
Exposures and outcomes stop with consideration of
the human receptor
Ecological Research
Agency is responsible for health of the entire
ecosystem
Physical condition along with chemical and
biological agents are primary stressors of concern
Multiple Receptors - individual plant or animal
species, communities of plants and animals, or
entire ecosystems
Receptors will vary across locations - location
will determine what receptors are present and the
circumstances for contact with the stressor
Risks are evaluated for multiple stressors, using
a systems approach
Exposures and outcomes can cascade when the
outcome in one receptor serves as the stressor for
another
Exposure and outcomes are of interest at
additional levels of biological organization
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Figure 2-3 (below) is an adaptation
of the source-to-outcome framework
developed by the National Research
Council (NRC, 1983, 1998).
The processes that are important
for exposure science start with a
stressor entering the environment
and end with dose characterization.
Starting in the upper left-hand
corner, stressors (primarily
chemical or biological) are released
into the environment from a source.
Many stressors can be transformed
through a number of processes,
including chemical reactions and
biological degradation. Stressors
or their transformation products
move through the environment and
can be found in environmental
media including air, water, soil,
dust, and food. The intensity of
exposure depends upon the stressor
concentration in the media, as well
as the duration of contact with the
receptor. Exposure becomes "dose"
when the stressor moves across the
receptor's body barrier. The text
under each box in Figure 2-3 shows
the information that is used to
characterize the various processes
represented in the boxes. The
arrows between the boxes represent
models that are used to link the
processes.
Source/Stressor
Characterization
Chemical
Biological
Environmental
Characterization
Atmosphere
Vegetation
Habitat Conditions
Hydrosphere
Lithosphere
Effects
Acute
Chronic
Transport and
Transformation
Flow Dynamics
Dispersion
Kinetics
Thermodynamics
Spatial Variability
Distribution
Temporal Variability
Meteorology
Dose
]
Environmental
Concentration
Absorbed Target
Air
Water
Soil/Dust
Food
Exposure
Pathway
Duration
Intensity
Frequency
Exposure
C
Receptors:
Individual
Population
Sensitive
Sub-population
Effects
Figure 2-3. Source-to-outcome framework for human health exposure research
8
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Figure 2-4 (below) shows that with
several modifications, the same
framework can be used to describe
the interaction of environmental
factors that contribute to ecological
exposures. For example, "source"
may also refer to activities that
give rise to non-chemical stressors,
such as changes to habitat from
expanding human populations.
"Environmental characterization"
includes the full suite of ecological
conditions, as well as those
that affect pollutant/stressor
concentrations. For ecological
research, "dose" is replaced by
an equivalent measure of the
stressor's impact on the receptor,
that is, stressor intensity within
the domain of the receptor. An
example of a quantity equivalent
to dose, where the receptor is a
stream's fish community, might be
the turbidity in a stream, caused by
excessive sediments, that prevents
a fish from finding its food. The
figure below illustrates the concept
that the receptor is determined
by the location and environmental
characteristics. Finally, the multiple
arrows from the effects box
illustrate a sequence of feedbacks
that can lead to cascading impacts.
For example, the response of an
ecosystem to a stressor might
include shifts in vegetation, which
would feed back to the exposure
pathway via environmental
characterization. Similarly, an
ecosystem response that includes
a change in microbial communities
could alter the biogeochemical
processes that affect transport and
transformation. In the ultimate case
of cascading exposures, an affected
organism may become the prey/
food for another organism, thus
entering the exposure continuum
directly as the immediate source
of exposure (environmental
concentration). Although there are
some circumstances (secondary
infection spread) in human
exposure research where exposures
and outcomes can loop back to
serve as stressors, this is not as
common and, thus, has not been
illustrated in Figure 2-3.
Source/Stressor
Characterization
Chemical
Biological
Physical
Environmental
Characterization
Acute
Chronic
ascadiiwlmpact
Transport and
Transformation
Internal Mass
Count
Length
Area
Environmental
Concentration
Atmosphere
Vegetation
Habitat Conditions
Hydrosphere
Lithosphere
Flow Dynamics
Dispersion
Kinetics
Thermodynamics
Spatial Variability
Distribution
Temporal Variability
Meteorology
Air
Water
Soil
Food
Pathway
Duration
Intensity
Frequency
Exposure
(
Receptors:
Individual
Community
Population
Ecosystem
Effects
Figure 2-4. Source-to-outcome framework for ecological exposure research
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Although
the source-
to-outcome
framework
for human
health and
the framework
for ecological
research have
been diagramed
separately in
this document,
it is important
to recognize
that the two
are closely
intertwined
and should be considered together.
Healthy ecosystems are required
for human well-being; they provide
clean air, water, and protection
from disease. In turn, humans are
part of these ecosystems and can
positively or negatively impact the
state of ecosystems through their
actions and management practices.
Exposure to environmental stressors
is considerably more complex
than illustrated in Figure
2-4. Multiple
stressors enter
the environment
at the same
time from
many different
sources.
Stressors
can remain
unchanged or
they can be
transformed
by physical,
chemical,
or biological
processes
to become
different
agents. These stressors or their
transformation products can
partition and move through many
different environmental media
(i.e., air, water, soil, sediment,
and the plant and animal life of
a particular region). Stressors or
their transformation products can
take many different
pathways to
reach the receptor. In the
simplest case, exposure to a given
stressor would be in a single
media through a single pathway,
although multimedia, multipathway
exposures are the more common
case. Definitions for concepts
associated with multimedia,
multipathway exposure are given
in the text box below. Aggregate
exposure is the sum of exposures
to a single stressor from all sources
and pathway(s) over a given time
period. Cumulative risks are
those that result from aggregate
exposures to a single stressor over
multiple time periods, or from
concurrent and/or synergistic
exposures to multiple stressors.
Exposure science must describe
the complexity of stressors, the
environment, and the receptors
as they interact. As examples,
when stressors from multiple
sources reach the receptor
by the same pathway,
it may be necessary
to determine
relative source
Exposure media:
environment or media in
which stressor exists as it
interacts with the receptor.
Exposure pathways
the course that the
chemical takes from its
source to the receptor.
Aggregate exposures
sum of exposure to a single
stressor from all sources
and pathways.
« ' >'<'-" *.. i', --"it > , i, - ,, '! 'n<'^i"j^f»i3WPr ..' jw»Ar?P<%J«« » . w*T , ...i ,« «»»!f"»'T «
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contributions.
Likewise, when
a stressor comes
in contact with
a receptor by
multiple pathways,
dosimetry must be
used to integrate
the exposures
as they would
lead to a health
outcome. Although
the concepts
of aggregate
exposures and
cumulative risk are relatively new
for human health exposure science,
understanding impacts of multiple
stressors from many different
sources has been a fundamental
aspect of ecological exposure
science that should be extended to
both disciplines.
Models are the underpinnings of
understanding and controlling
environmental health risks within
this basic framework for exposure
science. Exposure science
characterizes the movement,
chemical transformations, removal,
distribution, and interaction of
stressors and receptors in time and
space, at different locations and
on multiple scales. With such a
broad scope,
it is necessary to go beyond the
simple measurement of conditions
for each component of the
source-to-outcome framework
and focus on the processes that
control movement along the
framework. Models provide the
ability to summarize and link our
knowledge of exposure processes
and to mathematically quantify
and predict concentrations of
chemicals, biological and physical
conditions, exposures, and dose.
Process models enable us to be
both prospective and retrospective
in describing exposures and
outcomes. Moreover,
the assessment
of cumulative and
aggregate exposures
requires the use of
integrated multimedia
models. The use of
models is central to
Agency decision-making
processes (NRC,
2007). The EPA uses
models to inform the
exposure assessment
process (distributions,
uncertainty, and
variability), assess
compliance, and
evaluate alternate regulations.
As shown in the text box below,
there are many uses for exposure
models. Both conceptual and
computational models also allow us
to systematically evaluate our state
of knowledge as well as identify
data gaps and research needs. The
importance of models in exposure
science will continue to
increase as computational
methods advance.
Uses of Exposure Models
Research Uses:
* Provide exposure hypotheses
»> Synthesize data collected on
the state of a system
»> Provide explanations of factors
impacting exposure
Management Uses;
*** Assess exposure/dose to stressors
»> Project future conditions or
trends
<» Extrapolate to situations where
observations are not available
»> Assess the contribution of
individual sources
»> Evaluate the impacts of different
policies or future scenarios
<» Evaluate post-implementation
impact of regulations
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Throughout this framework, it is
important to distinguish between
exposure science and exposure
research.
Exposure science is applied
in the practice of assessing
and managing environmental
health risk; whereas exposure
research is conducted to address
critical gaps that will limit the
application of exposure science
and in this manner serves to
improve the quality of exposure
science. Specifically, exposure
research provides the scientific
understanding of the processes
involved in exposure science,
develops the tools (methods
and models) for conducting
the science, provides the data
that are used to understand
environmental and exposure
conditions, and provides inputs to
the models.
A complete exposure research
program in NERL must include
model development, observational
measurement research and
methods development. As already
discussed, modeling research
provides the underpinning for
exposure science. Observational
measurement studies provide
a fundamental understanding
of model processes, along with
inputs for models, and data
for model evaluation. Methods
research provides the tools that
allow observational measurements
to be made and interpreted.
These measurement tools also
have direct application for
compliance monitoring.
This document describes NERL's
exposure research program. NERL
recognizes that full understanding of
an environmental issue from source
to outcome can only be achieved
by conducting integrated, cross-
disciplinary, and focused research
and by applying the outputs of this
research to inform policy.
This can be achieved by NERL
exposure researchers working in
full coordination with toxicologists,
epidemiologists, engineers, risk
assessors, and decision makers both
within and outside of EPA. Research
responsibilities within ORD (EPA's
Office of Research and Development)
are organized around the source-to-
outcome framework. The engineering
laboratory (NRMRL) is responsible
for research that characterizes
sources; NERL is responsible
for research associated with fate
and transport, environmental
concentrations, exposure and dose;
and the health laboratory (NHEERL)
is responsible for characterizing
health outcomes associated with
exposures. The engineering laboratory
is also responsible for developing
and evaluating methods for source
reduction. Conducting integrated
multidisciplinary research with
scientists in these sister laboratories
is crucial to addressing the nation's
most important environmental
health issues, however developing
relationships with scientists in
academia, other governmental
organizations and nongovernmental
organizations is also needed to fully
develop integrated multidisciplinary
research programs. H<
-------
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Exposure science is applied in the practice
of assessing and managing environmental
health risk; whereas exposure research is
conducted to address critical gaps that will
limit the application of exposure science
and in this manner serves to improve the
quality of exposure science.
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3.0
Science
at U.S. EPA
3.1 Role of Exposure
Science in the Risk
Assessment/Risk
Management Context
The mission of the EPA is
to safeguard public health
and the environment from
environmental stressors. The
mechanism for environmental
protection is to minimize human
and ecosystem exposures to
stressors of concern as part of risk-
based assessments. The EPA sets
its priorities, targets its actions,
and measures its outcomes based
on assessing and managing risk.
Regardless of the Agency program
or regional office that raises
the issue, there are three broad
questions related to environmental
decisions (see text box below).
f
The mission of the EPA is
to safeguard public health
and the environment from
environmental stressors.
rf*-
^
to
< Is mitigation necessary?
(impact on the receptor)
<» How best to mitigate?
(impact on the stressor)
*> Was mitigation successful?
(accountability)
-------
Figure 3.1 (below) overlays
the concepts of stressor and
receptor on the source-to-
outcome framework. The figure
then incorporates the processes
associated with environmental
management practices, including
risk assessment, development
of environmental policies
and regulations, compliance
monitoring, and risk management.
Finally, the three questions that
face the EPA are overlaid in the
figure. As highlighted in the figure
and discussed below, exposure
is uniquely positioned at the
intersection of the stressor and the
receptor, and plays a pivotal role
in addressing each of the broad
Agency questions.
Is
Risk assessments are used to
determine whether mitigation
is necessary and they focus on
impacts to the receptor. All risk
assessments are based on the
concept that:
Risk = Exposure x Hazard
Exposure must be used implicitly
or explicitly to determine risk.
Very simply, risk assessment
is a four-step process (see text
box, right; NRC,1983). Hazard
identification determines
qualitatively, whether a stressor will
cause an adverse outcome. Dose-
response assessments establish the
quantitative relationship between
dose and the incidence of effects.
This information is used, in turn,
to develop a "safe" exposure level,
often referred to as a reference
dose (RfD). Exposure assessment
determines the route, magnitude,
" EPA Policy/
Regulation
I
Risk Assessment
(Receptor Impact)
Compliance
Monitoring
Risk Management
(Stressor/Exposure
Reduction)
I
to
111
Figure 3-1. Framework for protecting human health and the environment
16
-------
in
Process
Hazard Identification
Dose-Response Assessment
Exposure Assessment
Risk Characterization
frequency, and distribution of
exposure. Risk characterization
is conducted by comparing the
"safe" exposure level to the
distributions of exposure thereby
determining the risk of an adverse
outcome. Mitigation is required for
exposures at or above the "safe"
level. Although other information
along the continuum (i.e., sources,
environmental concentrations, etc.)
may provide inputs to the exposure
assessment, exposure is the metric
that is used to evaluate risk.
Risk assessments can be
conducted either by determining
dose-response using toxicity
studies coupled with an
independent exposure assessment
or by conducting environmental
epidemiology studies where
exposure estimates and health
outcomes are determined for a
specific cohort. Environmental
epidemiology is crucially dependent
on high-quality exposure estimates.
Although epidemiology may
not provide evidence of causal
associations, it does provide critical
information on measurable adverse
health effects in real populations
associated with exposure to real
environmental stressors.
How to
Risk to a receptor is most often
lowered by reducing exposure.
The "safe" exposure level is
determined by the dose response
assessment described in the
previous section. Activities
designed to bring exposures
down to that level are developed
using information on the
sources, pathways, and routes
that lead to the exposures.
These activities can be directed
toward various processes
along the source-to-outcome
continuum. Standards most
often target source controls or
environmental concentrations,
while some actions, such as
fish advisories or ozone alerts,
target individual actions in order
to reduce exposure. For those
standards that target environmental
concentrations, environmental
monitoring is used to assess
compliance. When monitoring
results exceed the standard, risk
mitigation activities are then
directed at the sources of the
environmental stressors.
Mitigation activities can be
developed without the use of
exposure tools and information,
however, ensuring the development
of activities that are the most
protective, with the least burden,
requires an understanding of
exposure. Exposure science
provides information on the levels
and processes that control fate and
transport, environmental conditions
and concentrations, and exposure
pathways. Techniques, such as
source apportionment and exposure
reconstruction, are used to relate
exposures or environmental
concentrations back to sources.
Monitoring methods are developed
to evaluate exposures and to assess
compliance to standards. Models
across the continuum are used to
summarize available knowledge
needed for regulatory decisions
and provide the ability to evaluate
alternative regulations, while also
offering a framework in which to
assess compliance (NRC, 2007).
-------
Over the last several years, there
has been an increased interest
in assessing the effectiveness of
EPA's regulatory and non-regulatory
decisions. Research and data
across the entirety of Figure 3-1
can be used to address this area.
This is a new area of research
for the Agency, with the initial
emphasis placed on developing
and validating indicators along
the source-to-outcome continuum
(USEPA, 2007). Exposure science
is expected to play a very important
role in this research area, because
it is crucial to linking stressor-
based metrics to receptor-based
metrics.
'&
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-------
3.2 RoleofExposurein
EPA Regulations
The EPA's regulations and policies
have been formulated to use
exposure information according to
the general principles outlined on
pages 16-18. However, depending
on the nature of the contaminant,
the environmental medium, and
the appropriate treatment of risk,
regulations may outline different
activities and address exposure
in either an explicit or implicit
manner. There are four primary
areas where the EPA can increase
the effectiveness of environmental
protection programs by enhancing
its emphasis on exposure
assessment, and investing in
exposure research:
1. Developing current
standards/policies
(e.g., developing and evaluating
exposure metrics and models
that can be used in the risk
assessment process, understanding
the mitigation or enhancement
of exposure by human activity
or natural processes, developing
and applying reliable exposure
indicators for environmental
epidemiology);
2. Achieving current standards/
policies
(e.g., developing analytical
methods to determine compliance,
developing and applying models
to predict the impact of mitigation
strategies, providing information to
implement mitigation and simulate
alternative scenarios and policies);
3. Evaluating the impact of
standards/policies
(e.g., reconstructing exposures
to determine environmental
concentrations of contaminants
relative to exposed populations,
developing and applying public
health indicators along the source-
to-outcome framework, evaluating
environmental concentrations
against model predictions); and
4. Developing the science
for the next generation of
standards/policies
(e.g., developing science for
assessing cumulative risks,
identifying sources of pollution
with the greatest risk, determining
the potential extent of exposure to
emerging contaminants).
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The text box on page 21 identifies
the major exposure elements of
the EPA's enabling legislation.
Identifying and understanding
those elements are critical to
strengthening and expanding the
Agency's use of exposure science.
Exposure has not often played a
large role in the risk assessment
and risk mitigation processes.
Environmental regulations were
often developed to address
contamination that was so severe
and immediate to its source that
ambient monitoring data or source
emissions were adequate surrogates
for exposure. The National Ambient
Air Quality Standards, developed
under the Clean Air Act, and the
EPA's drinking water standards,
developed under the Safe Drinking
Water Act, are but a few examples
of this approach.
This process worked well for the
EPA in the past and will continue
to work well for situations, as long
as certain conditions are met:
»J* The standard is not a risk-
based standard (e.g., best available
technology); therefore, the risk
assessment process is not used.
<» The surrogate exposure estimate
is either much greater or lower than
the risk level, thus better, more
realistic exposure information will
not change the action.
* There is only one source and
pathway of exposure, and the
relationship between source,
environmental concentration, and
exposure is well defined.
> There is only one pathway
for exposure, and the pollutant
concentration is relatively
homogenous, so that a single
measure of environmental
concentration can be used to
estimate exposure.
Understanding
exposures and
V.: mposmes
§& in
formed
decisions that protect
pubUc health and the
environment while
preserving human
well-being and
sustainability.
-------
Environmental Regulations and Statutes with Exposure Components
Clean Water Act- Establishes the structure for regulating the discharge of pollutants into U.S. waters.
Exposure information is used to set standards to achieve uses, determine achievability of uses via technology
and total maximum daily load (TMDL) controls (point, nonpoint sources), and establish watershed planning
and best management practices.
Safe Drinking Water Act- Establishes safe standards of purity and requires all public water systems to meet
primary standards. Exposure research is used to develop methods to improve exposure assessments, improve
microbial detection techniques, detect and classify unregulated contaminants.
Clean Air Act- Established National Ambient Air Quality Standards for the protection of public health and
the environment; sets limits on how much of a pollutant can be released in the air. Exposure research is
used to develop exposure metrics for epidemiological research that evaluates health impacts of criteria
pollutants, develop exposure assessments for air toxics, determine impact of atmospheric processes on air
quality, and provide models for air quality and exposure analysis and prediction.
Toxic Substances Control Act- Requires reporting and/or testing of industrial chemicals produced or
imported into the U.S. that may pose an environmental or human-health hazard. Exposure information is
used to develop methods to measure exposures to industrial chemicals, analyze and report exposure levels
based on real-world data, and to conduct exposure assessments on a wide array of chemicals.
Federal Insecticide, Fungicide & Rodenticide Act- Establishes federal control of pesticide distribution, sale
and use. Exposure research is used to develop methods and models to characterize exposures to pesticides,
model the fate and transport of pesticides through ground water.
Endangered Species Act - Prohibits any action that results in a "taking" of a listed species, or adversely
affects habitat of a listed species. Exposure information is used to determine (cumulative) risks to
individuals of endangered species (including habitat), and register pesticides based on exposure risk to
endangered species.
Food Quality Protection Act- Requires EPA to set limits on the amount of pesticides that may remain in or
on foods based on risks to infants and children from exposure from all sources. Exposure research is used to
develop important exposure scenarios, identify and quantify factors for children's exposure, develop high-
quantity, high-quality exposure data, develop models for estimating exposure and dose to pesticides.
Federal Food, Drug & Cosmetic Act- Requires EPA to address risks to infants and children from exposure
to pesticides in diets; requires the development and implementation of a screening program for endocrine
effects, including estrogenicity. Exposure information is used to study exposures to susceptible populations,
analyze exposures to endocrine disrupting compounds, develop generic techniques to model consumer
exposure.
Comprehensive Environmental Response, Compensation, and Liability Act - Provides EPA authority to
clean up and/or prevent releases of hazardous substances. Exposure science is used to specify testing and
monitoring requirements, determine appropriate groundwater remediation, determine the exposit to which
contaminated soils and debris must be excavated.
Resource Conservation and Recovery Act- Requires EPA to control the generation, transportation,
treatment, storage, and disposal of hazardous waste to protect human health and the environment. Exposure
science is used to measure chemicals at hazardous waste sites, assess risks for leaking underground storage
tanks, establish operation standards and promulgate monitoring and control regulations, and specify criteria
for acceptable location of treatment, storage and disposal of facilities.
-------
The need for good exposure
information is highlighted when
we consider the potential risks and
adverse outcomes associated with
underestimating exposures, along
with the potential costs to
society of overestimating
exposures. This is especially
true for situations where a
simple approach to exposure
assessment is not adequate
(see text box, right). In these
situations, the overall quality
of the risk assessment will be
limited, to a great extent, by
the quality of the exposure
assessment. As an example,
in risk assessments of
waterborne pathogens which
have a very large temporal
and spatial variability, the
uncertainty surrounding
the various components of
the exposure assessment
can easily be up to several
orders of magnitude. This
level of uncertainty can
have a profound impact on
the regulatory action that
is taken, as well as the
confidence in that action.
The EPA is facing a number of
new challenges for which a one-
pollutant, one-medium, one-
exposure approach for assessing
Assessments Requiring Refined
Exposure Estimates
> Aggregate exposures from multiple
pathways and routes
* Cumulative risks from exposures to
multiple stressors
* Exposures to stressors with significant
spatial and temporal variability (e.g., fine
particulate sulfate vs. coarse particulate
matter in air, chemical contaminants vs.
microbes in drinking water, etc.)
* Exposures and risks from sources rather
than to single pollutants from a source
< Total risk associated with regulatory
options
and managing risk is no longer
adequate. There is growing
awareness of potential exposures
to new types of contaminants
(e.g., nanomaterials), pressures
of population growth on
natural ecosystems, complex
systems that involve multiple
stressors, and pollutants
with significant spatial and
temporal variability (leading to
different exposure scenarios
^H for different populations).
Additionally, there is a
need to consider how the
consequences of a particular
risk management action
may lead to unintended
consequences. For example,
a regulation established
to reduce exposure to one
contaminant may increase
exposure to another
contaminant (e.g., decreases
in nitrogen loading in
streams may increase the
bioavailability of mercury).
Understanding exposures and
approaches for reducing exposures
will be critical in meeting these
challenges and in making informed
decisions that protect public
health and the environment while
preserving human well-being and
sustainability. &
'in,,
-------
T, A
The need for good exposure information
is highlighted when we consider the
potential risks and adverse outcomes
associated with underestimating exposures,
along with the potential costs to society of
overestimating exposures.
-------
-------
4.0 Exposure Research
arNERL
A s a research organization,
XAJMERL has two interrelated
goals: to provide leadership in
exposure science and to conduct
high-quality research to support
the EPA's mission. Achieving
these goals requires a strategic
approach that will inform not only
the research we do, but also the
processes we use to implement
this research. This conceptual
framework document is the
first crucial step in developing
and communicating such an
approach by providing a common
understanding of exposure science,
its role in supporting the EPA's
environmental protection agenda,
and subsequent implications for
the way NERL conducts business.
The consistent delivery of high-
quality, high-impact products
depends upon developing an
Financial
To achieve our goals,
how do we efficiently
allocate resources?
organization whose components
function to achieve its mission.
The first three chapters of this
framework describe a vision of
exposure science and the role of
NERL in achieving the Agency's
mission to protect the environment
and human health. Figure 4-1
illustrates how the business
of NERL the employees,
resources, and practices must
be aligned and in balance with
the development, production
and communication of research
products in order to fulfill that
vision. Thus, this final section
will discuss how the concepts of
exposure science, presented in
Sections 2.0 and 3.0 and Figure
3-1, provide the foundation for
NERL's research and management
practices.
Research Products
To have an impact,
what must we deliver?
Exposure
Framework
Vision/Strategy
1^^
Internal Business
Processes
To succeed, how do we
carry out our work?
Figure 4-1. Aligning NERL's business as a Strategy-Focused ,
Organization (Adapted from Kaplan and Norton, 2001)
Employee/
Organizational Capacity
To achieve our vision,
what competencies are
needed?
25
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The four elements of a strategy-
focused organization, outlined
below, address the direction NERL
is taking to achieve its mission.
1. Research Products:
We construct and deliver a portfolio
of relevant exposure research
programs that are responsive to the
Agency needs. (To have an impact,
what must we deliver?)
2, Internal Business Processes:
We use collaborative, creative, and
efficient processes to implement
our research. (To succeed, how do
we carry out our work?)
3. Employee/Organizational
Capacity: We recruit, retain,
and develop a work force with
the competencies needed to lead
our organization and conduct our
research. (To achieve our vision,
what competencies are needed?)
4. Financial Resources
Management: We allocate our
resources efficiently and effectively.
(To achieve our goals, how do we
efficiently allocate our resources?)
Developing and maintaining a
strategy-focused organization at the
laboratory level will enable NERL
to achieve its science mission,
create better solutions though
linkages, integration, and synergy,
ensure efficiency of research and
resources, leverage resources and
expertise, and provide a stable
environment for conducting and
completing research.
4.1 Research Products: To
have an impact, what must
we deliver?
For NERL to advance exposure
research in service to the Agency's
mission, the research products
must be well conceived, well
executed, and well communicated.
In this section, we address the
processes by which we identify
those strategic research directions
that will:
»> enhance environmental
protection through a better
understanding of exposure;
»> construct and execute a critical
path for research implementation,
and;
«> translate research into tools and
communication forms that best
serve our clients and partners.
-------
4.1.1 Developing a Research
Portfolio
For NERL's science leadership and
high-quality responsive research to
have an impact on environmental
protection, NERL's portfolio must
contain a set of programs that
address critical exposure science
needs directly related to the Agency
goals for air, water, and land
protection, as well as the health of
humans and ecosystems. To that
end, NERL's research portfolio
should be developed in alignment
with ORD's planning process,
including the Multi-year Plans
(MYPs). Developing NERL's range
of research programs is a dynamic
process that entails periodically
assessing the current programs and
identifying future areas of research.
Figure 4-2 (below) outlines the
factors that are used to evaluate
potential programs for inclusion in
our research portfolio.
Evaluation factors range from
questions about Agency priorities
to NERL's ability to advance the
state of the science. First and
foremost, the area of research must
be essential to EPA's and ORD's
environmental protection mission.
Also, and of great importance
to NERL, it must be exposure
research as articulated within this
document. Areas that pass though
these two initial filters are then
considered in light of several other
criteria.
For the many issues that meet
those broad considerations, any
decision by NERL to undertake
a research effort must take into
consideration the nature and
scope of the problem, the extent
to which it is being addressed
by others, and the likelihood of
having a significant impact. Does
NERL bring a unique capability
The proposed research should meet one or more of the following criteria:
Does it require
NERL's expertise or
unique facilities?
Does it require
an integrated
approach that only
NERL can provide?
Is exposure and
exposure data an
integral part of the
overall research
question?
Does the scope
and scale of
the research
require NERL's
involvement?
Is it a priority research
area for the Agency?
Is it the right time for
NERL's involvement?
Figure 4-2. Evaluation filters and criteria for assessing potential research areas
27
-------
,' IN
y -,»»v»
to the issue, either through
the Laboratory's expertise or
through unique facilities that
are unavailable elsewhere?
Does it require an integrated
multidisciplinary program? Some
research areas are well engaged
by other organizations and NERL's
incremental contribution would
add marginal value. Alternatively,
the problems within the area may
be so broad in scope or generally
intractable that NERL's efforts
would make insufficient headway to
justify the effort.
Ultimately, a research commitment
by NERL must be implemented by
its workforce, requiring that NERL
have the appropriate workforce
size, skill mix, and other resources
to address the issue.
4.1.2 Designing a Research
Program
Integrated, multidisciplinary,
exposure research programs are
developed for each program area
in NERL's portfolio based on the
principles of exposure science and
designed to be results-oriented
and customer-focused. Programs
should have clear priorities,
critical paths for meeting each
priority, and a set of products
and outcomes that demonstrate
the research effectiveness.
Appendix A on page 41 provides
an overview of how ORD identifies
the research outcomes required
by a given Multi-year Plan (MYP).
This section presents information
specifically related to developing
and implementing NERL's exposure
research programs to address the
goals developed in the MYP.
Because EPA is a mission-driven
Agency, all of ORD research is
applied. The types of research
required for environmental
protection and conducted by
NERL can be thought of as falling
into one of two complementary
categories: core and problem-
driven. Core research seeks to
understand the key biological,
chemical, and physical processes
that underlie environmental
systems, and leads to products
that may address issues common
to many EPA programs. Examples
of core research in NERL include
efforts to understand exposure and
factors responsible for exposure,
as well as research to develop
predictive models and tools for
describing exposure pathways of
stressors in human and ecological
systems. Problem-driven research
is directed at specific Agency
needs that arise due to regulatory
requirements or court-ordered
deadlines. In problem-driven
research, NERL brings existing
knowledge, tools, models, and
data to bear on high-priority
Agency problems, augmented by
limited, focused research efforts to
address gaps and deficiencies in
existing knowledge. An important
characteristic of problem-driven
research is that it be packaged
in forms that are most readily
communicated to and used by
the clients, especially program
offices. As an example of problem-
driven research, NERL develops
analytical methods for identifying
and defining unregulated drinking
water contaminants, which informs
EPA's Office of Water in setting
regulatory requirements of the Safe
Drinking Water Act. By maintaining
a portfolio that balances core and
problem-driven research, NERL is
best able to address the exposure
science research needs of the
Agency.
In all circumstances, research
programs are initiated by
first considering the Agency's
environmental protection goals
28
-------
and developing an understanding
of exposure issues related to
achieving these goals. As described
in Chapter 2, the Agency may
employ exposure science in
deciding whether mitigation is
necessary; in determining how best
to mitigate; and in establishing the
effectiveness of mitigation actions
or policies. Below are examples of
environmental protection questions
faced by the Agency that illustrate
each of these perspectives.
* Does exposure to particulate
matter 2.5 micrometers or smaller
in ambient air cause death and
hospitalizations?
* How should the introduction
of invasive species through ballast
water discharge be regulated?
* Have the efforts to control
mercury in combustion sources
resulted in a measurable decrease
in the levels of mercury in the
environment, leading to reduced
exposures to humans and
ecosystems?
Articulating such questions
and translating them into
scientific objectives are the first
steps in outlining a research
implementation plan. Overlaying
these questions onto the source-to-
outcome conceptual model helps
develop the context for the role of
exposure, assists in constructing
the critical path for the research,
and aids in identifying key partners
and points in integration. Once a
critical path for achieving those
scientific objectives is outlined,
the current limitations of exposure
science and the critical needs
for exposure data, methods, and
models are determined. Should
the science needs exceed NERL's
ability to address them, NERL
directs its research efforts towards
those questions that either have the
greatest uncertainty or provide the
greatest opportunity for advancing
science to support exposure and
risk assessment.
4.1.3 Communicating NERL's
Research
Conducting cutting-edge research
is not enough. To have an impact,
the results of our research
programs must be communicated
to our customers, stakeholders,
partners, and to the scientific
community. NERL's communication
strategy for research will focus on
having a high impact in advancing
environmental protection and the
state of exposure science.
To be recognized as leaders
in the research community,
NERL scientists must publish
in high-impact, peer-reviewed
journals. Other activities such
as membership in professional
societies, participation on editorial
review boards and science advisory
committees, and development
of workshops, workgroups and
committees are also required.
Communication within the
scientific community maximizes the
exchange of ideas and approaches
to support the Agency's mission.
Measures of success in this area
include peer-reviewed publications,
reports rated as highly-cited and
publications rated as
having high-impact.
NERL
must also
ensure
that our
research
is used by the Agency by delivering
high-quality, high-impact
products to our clients. Working
cooperatively, NERL scientists,
Division Directors, Associate
Directors, and Assistant
Laboratory Directors must
make certain that NERL
research products, which
include peer-reviewed
software, methods, reports, and
journal articles, are strategically
29
provided to its customers for use
in their decision-making. NERL
should promote implementation
of its tools within the Agency by
providing workshops, Internet
downloads, and user manuals that
advance these tools and models.
NERL will also demonstrate the
intended use of its high-quality
methodology through case studies
and pilot programs with its
partners. Finally, NERL should
track its results against metrics for
success, including bibliographic
analysis, citation indices, and
customer use or satisfaction
surveys.
-------
4.2 Internal Business
Processes: To succeed, how
do we carry out our work?
NERL believes that sound science
can only come out of a sound
organization that ultimately
what we do depends on how
we do it. Forging an effective,
responsive research
organization out of many
talented individuals and
geographically-separated
divisions requires
a shared, cohesive
vision of ourselves,
commitment to a set
of working principles,
and the development of
business practices that
integrate and leverage our
capabilities.
4.2.1 Management
Principles
NERL, as a laboratory, is
committed to conducting
high-quality, relevant
exposure research
in an integrated,
multidisciplinary,
collaborative, and
effective manner. Our
management processes
are crucial to achieving
this goal and should
promote our core
organizational principles.
The core principles
that underpin NERL's
structures and management
processes are articulated in the
following paragraphs.
<» We are the National Exposure
Research Laboratory.
The title NERL embraces several
important principles. We think
and act as a single laboratory. We
provide leadership at national and
international levels in exposure
science. Finally, the EPA is the
client base, thus NERL must
plan and conduct its research
based on direct consultation and
communication with our clients
within the Agency.
*J» Science comes first.
We need to understand where
we are going with our science,
and then manage ourselves and
our resources to get there. As a
corollary, NERL will develop and
use only those processes that are
required to manage its science.
NERL will not use processes that
are more complex than needed to
achieve its science goals.
*J» Apply multidisciplinary
approaches where applicable.
The EPA is faced with many
large, complex problems that
are often best addressed with
multidisciplinary research programs
that use cutting-edge research
tools. Developing an environment
that fosters such collaborative,
multidisciplinary research will
set us above other organizations.
This concept applies to research
we conduct within NERL as well
as research that is
conducted across ORD.
Collaborative research
allows scientific
processes to be used
in understanding
and managing the
impact of stressors
as they move from
sources to humans and
ecosystems. This brings
multiple perspectives
to a problem for better
solutions, and provides
opportunities to leverage
NERL's state-of-the-
science knowledge and
skills in multiple areas.
«t» Seek functional
solutions first.
Organizations often
use structural fixes to
deal with functional
problems and this
usually does not work.
NERL should be able to
work within the current
structure and optimize
its implementation
processes to achieve the
established goals.
»J» Optimize use of existing
resources.
NERL has an impressive array
of resources to accomplish its
mission. Additionally, the Agency
has many different high-priority
problems to address. NERL will
strive to optimally align its existing
resources, including staffing,
with the highest-priority Agency
problems that require exposure
science.
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4.2.2 Management Processes
Several processes must be in
place for NERL to implement
an optimized cross-laboratory
research program. These processes
should allow NERL to fully
integrate planning across the
laboratory; optimize use of staff,
research dollars, and facilities;
and efficiently manage resources.
If successfully executed, they
should serve as a starting point
for changing the laboratory
culture and moving forward.
Importantly, they will allow NERL
to work together as a laboratory
to produce relevant, high-quality
research results.
Implementation Plans and
Divisional Business Plans are the
documents that fully articulate
what we do and translate into
how we do it. For those plans to
be effective, they must be shaped
and informed by the strategic
directions as developed above
and fully integrated across
the laboratory. Currently,
Implementation Plans serve
as the basis for planning and
should provide the mechanism ty
for integration. Each plan is ^
intended to develop a focused, B|:<
integrated research program
that is conducted to solve
a complex environmental
problem of national
significance. The process
is designed to consider the
Agency's highest priority
needs and NERL's resources in
addressing key Agency needs.
Developing and conducting
a set of well-integrated
research programs at
the laboratory level is an
optimization challenge.
Each Implementation Plan
must direct NERL resources
to address the high-priority
exposure associated with an
environmental problem. The full
set of plans must optimally deploy
those resources to move exposure
science forward. Thus, prior to
developing individual plans,
NERL must look across plans to
prioritize the research and identify
leveraging opportunities (see text
box below). It is understood that
the highest-priority research should
be resourced first. However, as
a part of this process, resources
(staff and FTEs) must also be
Basis for Prioritizing Research
»> Agency needs
< Ability to demonstrate an impact
»> Ability to make a unique
contribution
<* Appropriate balance between
core and problem-driven
research
balanced across both divisions
and plans. The overall goal is to
ensure that sufficient resources
are available for successfully
conducting the most relevant
and responsive research in those
areas where NERL plans to make
a commitment. Understanding
the priorities and the distribution
of resources will also allow NERL
to make informed decisions
about redirecting resources,
when needing to respond to new
initiatives or when faced with
reduced resources. Finally, NERL
should use the information on
science priorities and proposed
research to direct workforce
planning (as described in section
4.3).
A number of non-traditional
approaches will be needed
to staff and implement
multidisciplinary research across
NERL. The primary goal is to
ensure that critical expertise is
,;,,,, provided to all programs across
the laboratory. Other goals
include greater efficiency,
increased collaboration,
development of new skills and
capabilities, advancement
:«f of new technologies, and
₯'' increased scientific leadership.
Centers of Excellence
x-i (COE) are envisioned as one
approach for efficiently using
critical technical expertise
in integrated laboratory
research programs. The
general concept for a COE is
based on identifying research
areas or capabilities of
_,.< common need that present
:":: opportunities for leveraging
facilities and experienced
staff to optimize technical
performance. Potential areas
for establishing COEs include
the development of analytical
methods and technologies, and
the application of statistical
methods and informatics.
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In addition to the challenges
presented by planning and carrying
out research in a number of high-
priority areas, NERL faces the
challenge of creating integrated,
multidisciplinary research programs
across six divisions in four
locations. NERL has traditionally
managed much of its research
at the level of the individual
researcher or branch; however,
creating an integrated exposure
program will require nontraditional
approaches to management.
Creating and embracing this
exposure framework is a
prerequisite for NERL to function
as a single national exposure
laboratory. With a common vision,
NERL can be unified in purpose
and in action. The development
of implementation plans by
researchers from across NERL, who
have been challenged to plan from
a NERL-wide perspective, is also
essential for creating an integrated
exposure program.
Finally, the research, once
planned, needs to be executed
in an integrated fashion; across
disciplines, across the source-
to-exposure pathway, and across
locations. To that end, NERL is
exploring organizational practices
and new technologies that promote
collaboration and integration,
such as virtual teams and Web-
based communications. As NERL
moves forward, it is important to
identify and implement proven
and time-tested best management
and organizational practices; to
seek the counsel of organizational
leaders and consultants to guide
the process; and to commit to
adopting management systems that
simplify rather than complicate
laboratory operations.
4,3 Employee/
Organization Capacity: To
achieve our vision, what
competencies are needed?
Achieving NERL's goals to provide
leadership in exposure science
and conduct high-quality science
to support EPA's mission requires,
first and foremost, that we have
scientists with the necessary
skills to conduct cutting-edge
exposure research. We must also
have a workforce that embraces
the concept of integrated,
multidisciplinary research programs
and that has the flexibility to adapt
to changing technical demands
and changing organizational needs.
Finally, we must develop leadership
throughout the organization
to successfully meet today's
challenges and the challenges
of the future. This section will
discuss the concepts for strategic
workforce planning and approaches
for developing our leaders within
NERL.
4,5.1 S era regie Workforce
Planning
NERL has a number of challenges
when developing a strategic
workforce plan. As with all Federal
organizations, we have a very stable
workforce with little staff turnover;
-------
yet we are a scientific organization
that must keep pace with the
newest science and changing
science needs. Thus our planning
must identify those critical areas
where we need expertise and the
number of staff/researchers needed
in each area. We must also develop
strategies for providing more
flexibility within the workforce.
Finally, we want to identify,
develop, and reward staff who work
across organizational boundaries,
who participate in integrated,
multidisciplinary research and who
can adapt to new technologies and
new problems.
NERL is a large research
organization with six divisions in
Stressor Characterization,
Fate and Transport
Air
Atmospheric Characterization
Atmospheric Processes
Air Quality Modeling
Meteorology
Source Apportionment
Climate
Water
Water Methods
Water Processes
Microbial Processes
Surface Water Modeling
Land
Site Characterization
Soil Chemistry
Soil/Sediment Processes
Ground Water Modeling
Vapor Intrusion
four geographical locations. Each
division has a unique history that
has led to strengths within various
scientific disciplines. Nonetheless,
the workforce within these divisions
and across NERL as a whole should
possess a diverse set of skills
and expertise that can be used to
address complex exposure research
questions.
Figure 4-3 (below) depicts the
varied expertise that will be
required to address the full
range of exposure issues for both
human health and environmental
protection. The box on the left-
hand side of the figure shows
the scientific expertise needed
to assess stressors and their
movement throughout the
Exposure
environment. The box on the
right-hand side shows the
needed expertise to describe
the distribution, behaviors, and
characteristics of the receptor that
will lead to exposure and dose.
The box at the bottom of the figure
shows the technical expertise that
cuts across disciplines and is used
to address important exposure
issues.
A work force consisting of only
principal investigators, even if
all of the required disciplines are
represented, is not sufficient to
carry out a program of exposure
research. In order to provide a
stable environment for conducting
and completing our research, NERL
must develop a self-sustaining
workforce that can operate
independently of ORD's changing
Receptor Characterization
Ecological
Landscape Science/Characterization
Aquatic/Watershed Ecology
Wildlife Distribution Modeling
Multimedia Modeling
Ecosystem Diagnostics and Forecasting
Ecological Indicators
Human
Human Exposure Characterization
Microenvironmental Characterization
Fate and Transport
Human Exposure Modeling
Dose Modeling
Exposure Indicators
Human Physiology and Activity
Cross-Cutting Scientific Expertise
Analytical Methods
Statistical Analysis
Geographic Information System
Bioinformatics
Omics
Remote Sensing
Figure 4-3. Scientific expertise for exposure research
33
-------
budget. Our staff must include
both principal investigators and
staff who can provide technical
support for these investigators.
With this approach, all of our
scientists can still maintain critical
science programs regardless
of funding levels. As funding
increases, additional work can be
accomplished using extramural
mechanisms.
A strategic workforce plan should
evaluate the core science that we
conduct and the critical expertise
and numbers of staff (both Pis and
technical support staff) needed to
conduct this science. To effectively
leverage our resources and to
provide the greatest flexibility, this
analysis should be done not only
at the divisional level but also at
the laboratory level. Structures
such as the NERL-wide Centers of
Excellence can be used to maintain
the intellectual base for the
expertise that provides technical
input to all exposure research
across the laboratory (see lower box
in figure 4-3). Since the workforce
in NERL is very stable, we must
be able to anticipate scientific
workforce needs five to ten years in
advance. It is very important that
our planning also include education
and training for our current staff
to insure that everyone has state-
of-the-art skills and understands
how these skills can be applied
to important exposure issues.
We must also devise strategies
for obtaining scientific expertise
rapidly in new areas as they
emerge.
Finally, as we hire new staff,
we must ensure that our hiring
strategies identify not only the
scientific expertise that is required
but also the core set of traits
and competencies that our staff
must possess to be effective
contributors in NERL. As examples,
traits and competencies that
would be consistent with the
goals set forth in the framework
would include: commitment
to NERL's mission, innovative,
communicative, professional,
flexible, forward-thinking, and
It is important that NERL's planning
include education and training for
staff to insure that everyone has state-
of-the-art skills and understands
how these skills can be applied to
important exposure issues.
collaborative. Individuals with
these attributes will enable NERL
to advance exposure science and
address the Agency's most pressing
environmental protection issues
through cutting-edge, integrated
multidisciplinary research.
4.3.2 Leadership Development
within the Workforce
NERL is its people and every
individual in the laboratory must
feel responsible and
work towards
its success.
34
-------
Thus, it is important that we
develop individual leadership at all
levels throughout the organization.
For continued success, we must
also promote organizational
leadership by developing our next
generation of leaders.
Consistent with the principles of
a strategy-focused organization,
leadership development will be
derived based on the concepts set
out in the exposure framework,
which defines who we are,
what we want to excel
in, and what we
want to be
known for.
From this starting point, both
the individual and organizational
traits and competencies required
for leadership throughout the
organization can be identified.
Individual competencies would
address scientific, programmatic,
and organizational leadership.
Organizational competencies
would address the direction of the
organization what we excel in
and what we are known for.
Understanding our direction and
developing a list of traits and
competencies for leadership in the
organization is a critical first step
toward leadership development
in NERL. Our leadership vision
and competencies must then be
communicated throughout the
organization, so every individual
knows what they should be striving
for in their development efforts.
Leadership programs specifically
targeted toward essential traits and
competencies need to be developed
and implemented throughout the
organization.
Finally, we must mentor, encourage,
and reward our staff as they develop
and use the requisite leadership
skills. To be successful, leadership
development must be a continual
process and truly reflect NERL
based on who we want to be.
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4.4 Financial Resources
Management: To achieve
our goals, how do we
efficiently allocate
resources?
For NERL's researchers and staff
to achieve the objectives outlined
in this framework, they must be
supported by capital and financial
resources buildings and
equipment, administrative and
technical support, and an adequate
budget. This requires the effective
and efficient allocation of financial
resources. The need to leverage
those resources and to promote
science integration lead us to
perform that allocation with both
NERL-wide and division-specific
perspectives in mind. The business
plans prepared by each division
must be developed in concert and
with complementary
elements, in
order
to achieve the NERL objectives
of resilience, optimization, and
integration.
4.4.1 Financial Resilience
Historically, NERL has used its
financial resources to enhance its
scientific capabilities, employing a
number of mechanisms to provide
research support to its principal
investigators. As uncertainty
in budgets has increased and
effective funding levels decreased,
NERL has been moving to a model
of supporting research with in-
house staff. During the transition,
extramural funds will continue to
support in-house research as well
as address high-priority acquisition
needs. Funds that support in-house
research are provided to divisions
in a manner that reflects the
size, productivity, and discipline-
specific demands of its investigator
workforce, whereas the priorities
for extramural acquisitions
are determined as part
of the ORD planning
process.
4.4.2 Optimization and
Integration
The optimal distribution of
financial resources across NERL
should both sustain the critical
scientific capabilities to advance
exposure research and promote
the integration of organizations
and scientific disciplines to
that end. Research planning
at both the strategic and
implementation levels lays the
critical path for NERL research.
Planning collectively promotes
the transparent and effective
deployment of budgetary resources
at each stage of that critical
path. Similarly, the acquisition
and maintenance of cutting-edge
facilities and instrumentation are
essential to a high-performing
workforce. Planning for large
capital investments, then, must
align with the highest priority
research as well as the potential for
collaborative use of the facilities
and instruments. H
,.. .Uljfcliftafe
i^>C
»- =-|«l=.-r--r^,
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Any decision by NERL to undertake a research
effort must take into consideration the nature
j+j
and scope of the problem, the extent to which it
is being addressed by others, and the likelihood of
having a significant impact.
-------
Integrated* multidisciplinary, exposure
research programs are developed for each
program area in NERLts portfolio based on
the principles of exposure science and designed
to be resuks-oriented and customer^focused.
'*«»' 4
«.,/»,! "fm»-
*fkA 4r :-*ti.
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References
Kaplan, R.S., Norton, D.P., 2001. The Strategy-Focused Organization: How Balanced
Scorecard Companies Thrive in the New Business Environment. Harvard Business
School Press, Boston, MA.
Kolpin, D.W., Furlong, E.T., Meyer, M.T., Thurman, E.M., Zaugg, S.D., Barber, L.B.,
Buxton, H.T., 2002. Pharmaceuticals, Hormones, and Other Organic Wastewater
Contaminants in U.S. Streams, 1999-2000: A National Reconnaissance.
Environmental Science and Technology, vol. 36, no. 6, p. 1202-1211.
NRC, 1983. Risk Assessment in the Federal Government: Managing the Process. The
National Academies Press, Washington, DC.
NRC, 1998. Research Priorities for Airborne Particulate Matter: I. Immediate Priorities
and a Long-Range Research Portfolio. The National Academies Press, Washington,
DC.
NRC, 2004. Air Quality Management in the United States. The National Academies Press,
Washington, DC.
NRC, 2006. Human Biomonitoring for Environmental Chemicals. The National Academies
Press, Washington, DC.
NRC, 2007. Models in Environmental Regulatory Decision Making. The National
Academies Press, Washington, DC.
Underwood, A., 2007. Rivers of Doubt. Newsweek, 149(23):58, 60.
USEPA, 1992. Guidelines for Exposure Assessment. U.S. Environmental Protection
Agency, Washington, DC, EPA/600/Z-92/001.
USEPA, 1998. Guidelines for Ecological Risk Assessment. U.S. Environmental Protection
Agency, Washington, DC, EPA/630/R-95/002F.
USEPA, 2003. Framework for Cumulative Risk Assessment. U.S. Environmental Protection
Agency, Washington, DC, EPA/600/P-02/001F.
USEPA, 2004. Air Quality Criteria for Particulate Matter. U.S. Environmental Protection
Agency, Washington, DC, EPA 600/P-99/002aF-bF.
Zartarian, V., Bahadori, T, McKone, T, 2005. Adoption of an Official ISEA Glossary.
Journal of Exposure Analysis and Environmental Epidemiology, vol. 15, p. 1-5.
39
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Appendix A
NERLs Research Within the Context of ORD
The EPA's research agenda is
determined by means of a research
planning process involving every
organizational level within the
Agency. Figure A-l is a simplified
diagram for this process. ORD's
research is driven by the five
Agency goals described in the U.S.
EPA's Strategic Plan (www.epa.gov/
ocfo/plan/plan.htm). Within each
goal, ORD works in partnership with
numerous stakeholders to identify
the highest priority research
topics. The objective is to focus
on environmental problems that
pose the greatest risk to people
and the environment; to reduce
uncertainties which will improve
our ability to identify risks; and to
clearly help the Agency fulfill its
regulatory mandate. For each goal,
ORD commits to reaching certain
milestones and delivering specific
products within a given time
period.
ORD's Multi-Year Plans (MYP)
provide the long-term (5 to 10 year)
focus for a given area of research,
integrating efforts across all of
ORD's Labs and Centers. For each
MYP, an ORD team conceptualizes
a framework for the research
with long-term goals that will be
addressed across ORD. NERL plays
a vital role in the development of
the MYPs. All of NERL's research
is included in these plans, and the
Laboratory is held accountable for
meeting commitments contained in
MYPs.
NERL develops research
Implementation Plans, using
ORD's MYPs as roadmaps. The
Implementation Plans bring the
planning process to the operational
level within the Laboratory.
Separate plans are developed
for each of ORD's MYPs and are
Congress
Promulgates Environmental Statutes
intended to develop focused and
integrated programs. For each
Implementation Plan, steering
committees made up of scientists,
Associate Laboratory Directors,
and Managers within NERL and
across the Agency are charged
with identifying the important
programmatic research questions.
Scientists across the Laboratory
are then tasked with developing
specific research programs to
address these questions.
In summary, while the problems
NERL is tasked to solve are defined
by the Agency's planning process,
the research agenda for solving
those problems is determined by
NERL and its staff. Although the
relative emphasis in topic areas
may change as ORD priorities
and budgets shift, substantial
efforts are made by NERL to build
and maintain research programs
that are relevant to the scientific
problems and responsive to the
Agency needs.
EPA / Sets ,
national
Strategic Plan
ORD
Multi-Year
Plan
Scientist
environmental
goals
Establishes research
priorities; formulates
critical scientific questions,
long-term goals, and
major milestones
Maps out research agenda in context
of ORD priorities; identifies critical paths
Devises approaches for
addressing scientific uncertainties
Conducts research; postulates hypotheses and
develops/uses methodologies to test hypotheses
NERL
Division
Research
Implementation Plan
Research Plan
Projects
Figure A-l. Research planning in EPA
41
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I
Acronyms
BOSC Board of Scientific Counselors
COE Centers of Excellence
EPA Environmental Protection Agency
FTE Full Time Employee
MYP Multi-year Plan
NERL National Exposure Research Laboratory
NHEERL. National Health and Environmental Effects Research Laboratory
NRC National Research Council
NRMRL National Risk Management Research Laboratory
ORD Office of Research and Development
PI Pri nci pa I I n vestigator
RfD Reference Dose
TMDL Total Maximum Daily Load
USEPA United States Environmental Protection Agency
42
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cvEPA
United States
Environmental Protection
Agency
PRESORTED STANDARD
POSTAGE & FEES PAID
EPA
PERMIT NO, G-35
Office of Research and Development (8101R)
Washington, DC 20460
Official Business
Penalty for Private Use
S300
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