EPA 601/K-15/002 I September 2015 I www.epa.gov/research
United States
Environmental Protection
Agency
                           Human Health
                        Risk Assessment
           STRATEGIC RESEARCH ACTION PLAN
                                      2016-2019
  Office of Research and Development
  Human Health Risk Assessment

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                                EPA 601/K-15/002
Human Health  Risk Assessment
   Strategic Research Action Plan 2016 - 2019
          U.S. Environmental Protection Agency
                September 2015

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Table of  Contents
 List of Acronyms	ii
 Executive Summary	1
 Introduction	2
 Environmental Problems and Program Purpose	3
     Problem Statement	5
     Program Vision	5
 Program Design	5
 Research Program Objectives	12
 Research Topics	17
     Topic 1: Integrated Risk Information System (IRIS)	18
     Topic 2: Integrated Science Assessments (ISAs)	20
     Topic 3: Community and Site-Specific Analyses	22
     Topic 4: Advancing Analyses and Applications	26
 Anticipated Research Accomplishments and Projected Impact	32
 Conclusions	34
 References	35
 Appendix A: Proposed Outputs, Human Health Risk Assessment Research Program, FY2016-19	37
 Appendix B: Executive Orders and EPA Policies HHRA Supports	42
 Appendix C: Research Program Partners and Stakeholders	43
 Appendix D: Enhancements to IRIS Program	44

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List of Acronyms
ACE          Air, Climate, and Energy Research Program
AOP          Adverse Outcome Pathway
BMDS        Benchmark Dose Software
CAAC        Chemical Assessment Advisory Committee
CASAC       Clean Air Scientific Advisory Committee
CRA          Cumulative Risk Assessment
CSS          Chemical Safety for Sustainability Research Program
EDSP        Endocrine Disrupter Screening Program
HS           Homeland Security Research Program
HTS          High-throughput screening
IRIS          Integrated Risk Information System
ISA          Integrated Science Assessment
MCDA        Multi-criteria decision analysis
MCL          Maximum Contaminant  Level
MIE          Molecular Initiating Event
MOA         Mode of action
MSD         Multipollutant science documents
NAAQS       National Ambient Air Quality Standard
NRC          National  Research Council
OAR          Office of Air and Radiation
OSWER       Office of Solid Waste and Emergency Response
OW          Office of Water
PAL          Provisional Advisory Level
PM           Particulate matter
PPRTV       Provisional Peer-reviewed Toxicity Values
RATE        Risk assessment training and experience
RfC          Reference Concentration (inhalation)
RfD          Reference Dose (oral)
SAB          Science Advisory Board
SHC          Sustainable and Healthy Communities  Research Program
SSWR        Safe and Sustainable Water Resources  Research Program

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Executive Summary
To protect human health and the environment, state, local and federal governments, and others,
must make daily decisions about the risks of exposures to environmental contaminants. EPA has
designed the Human Health Risk Assessment program  to develop and apply state-of-the-science
risk assessment methods to estimate human health and environmental risks from exposures to
individual chemicals, chemical mixtures,  and mixtures of chemicals and  non-chemical stressors
to support and  improve environmental decisions. This program identifies, evaluates, integrates,
and translates existing and emerging scientific information from diverse scientific disciplines to
accurately assess hazard and characterize risks.

This plan highlights  how the HHRA program was developed with input from EPA program  and
regional offices and from external sources, including nonprofit and research organizations, private
industry, and scientists from a range of disciplines across the academic community. The program
emphasizes stakeholder engagement to both inform the development of its assessment products,
as well as to gain feedback on the utility of products to users.

The HHRA program is designed to  provide a  comprehensive set of risk assessment products
and analytical  approaches  that  will support a wide  range  of  environmental management
decisions. The research objectives of the program are:

        Objective 1: Characterize risks
        Efficiently support a range of decision making with an agile, fit-for-purpose portfolio
        of robust and responsive assessment products that characterize risks and potential
        impacts to human health and the environment.

        Objective 2: Advance and refine assessment approaches
        Refine risk assessments by identifying critical issues and advancing analytical approaches
        and applications to incorporate new science, methods and technologies.

        Objective 3: Enhance and engage
        Enhance data access and management systems to support transparency and efficiency;
        provide  outreach and engage stakeholders to ensure support, training, and tailoring of
        assessment priorities and products.

To achieve these overarching objectives and address their respective scientific challenges, research
projects are organized into  four topic areas: (1) Integrated Risk Information System  (IRIS); (2)
Integrated Science Assessments; (3) Community and Site-specific Risk; and (4) Advancing Analyses
and Applications. In concert the topics provide priority assessment products, identify critical issues
as they arise, and develop or stimulate advances in approaches and solutions to address emerging
challenges, incorporate innovations, and continuously refine applications. Ultimately, this research
helps to ensure that risk-based decisions by federal, State, local, and tribal agencies and the public
to protect public health and the environment are based on  reliable, transparent  and  high-quality
risk assessment  methods, models, and data.

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Introduction
Every day, the U.S.  Environmental  Protection
Agency  (EPA)  and  its  diverse  stakeholders
must  make  decisions  to  protect   human
health and the environment from the known
or potential adverse effects  of  exposure to
environmental  pollutants.   Such  decisions
span a large regulatory landscape and require
different degrees  of environmental pollutant
risk information:  developing health-protective
reference  values  to support air, water  and
waste management  programs; evaluating data
on chemicals provided  in pre-manufacturing
notices; characterizing   potential  public  and
environmental health impact during emergent
situations;  screening  and   prioritization  of
chemicals  for monitoring at  Superfund  sites
and in the air and  water; evaluating health and
ecological  effects  data  to derive benchmark
estimates; and the interpreting and  integrating
of different  lines  of  evidence  to  support
decisions to establish, retain or revise  national
pollutant standards. EPA's Human Health  Risk
Assessment  (HHRA)  program is  designed to
provide  robust and responsive risk assessment
support  to  risk   management  decisions
aimed at  protecting human  health  and  the
environment. The HHRA program is the world
leader in providing both an  essential  portfolio
of risk assessment products and in undertaking
targeted and innovative methods development
to advance risk analysis.

This  Human Health Risk Assessment (HHRA)
StRAP presents the strategic plan  for  this
national program to develop support to Agency
decision making  and regulatory  actions.  The
HHRA plan is one of six  research plans, one for
each  of EPA's national  research  programs in
ORD. The six research programs are:

• Air,  Climate, and Energy (ACE)
• Chemical Safety  for Sustainability (CSS)
• Human Health Risk Assessment (HHRA)
• Homeland Security Research Program (HSRP)
• Safe and Sustainable Water Resources
  (SSWR)
• Sustainable and Healthy Communities (SHC)

The HHRA plan articulates how this program is
integrated into the  overall  research portfolio
of the  Agency's  Office  of  Research  and
Development (ORD), so as to most efficiently
and  best  apply  that research   to  identify
hazards, characterize potential human health
and environmental risks, and to inform, engage,
and develop capacities of its assessment clients.
The 2016 - 2019 StRAP for the HHRA national
program  was developed using considerable
input and  support from partnerships  with
EPA  program and   regional  offices  requiring
risk assessment products, as well as outside
stakeholders, nonprofit  human   health  and
research  organizations, private industry, and
colleagues  across  the scientific  community
involved in human  health and ecological risk
assessment.

EPA's strategic research action plans lay the
foundation for EPA's research staff and  their
partners to  provide focused  research efforts
that  meet the Agency's legislative mandates,
as well as the goals outlined in the Agency's
Fiscal Year 2014 -  2018 EPA Strategic  Plan.
They  are  designed to  guide an ambitious
research  portfolio that at once  delivers the
science and engineering solutions  the Agency
needs to meet such  priorities, while cultivating
a new paradigm  for efficient, innovative, and
responsive   government   and  government-
sponsored  environmental and human health
research and scientific assessment.

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No  other research organization in the world
matches the diversity and breadth  represented
by the collective scientific and engineering staff
of EPA's Office of Research and Development,
their grantees, and  other partners. They are
called upon to conduct research to meet the
most  pressing environmental and  related
human health challenges facing the nation and
the  world.

Environmental

Problems  and  Program

Purpose

Decision  making in the Agency  and  by its
stakeholders to protect public  health and the
environment covers a  large landscape of risk
assessment activities and  requires agility to
bring the best available science and technologies
to inform those decisions in a fit-for-purpose
fashion. The purpose of the Human Health Risk
Assessment program is to develop and apply
state-of-the-science risk assessment methods
to estimate human health and environmental
risks from exposures to  individual chemicals,
chemical mixtures,  and mixtures of chemicals
and  non-chemical  stressors to support  and
improve environmental decisions. The HHRA
program  identifies, evaluates,  integrates  and
translates  existing  and emerging scientific
information from diverse scientific disciplines
to accurately assess hazard and  characterize
risks.

The HHRA portfolio of assessment applications
ranges from  rapidly estimating  hazards for
screening and  prioritization for further testing
and  assessment,  through  development  of
provisional assessments for site-specific cleanup
decisions, to  extensively vetted assessments
in support of decisions on national standards.
Identifying critical  issues and research needs,
as well as providing advances in analyses and
application of new  data and tools, are critical
components  necessary to keep assessment
products credible and contemporary with the
state of  the science. The HHRA program  is
uniquely positioned to advance new approaches
in support of the  risk  management decisions
and regulatory needs of various stakeholders,
including Agency program  and regional offices
as well as state/tribal environmental protection
programs and interested communities.

The significant impact of  the HHRA program
is  demonstrated in the use of its assessment
products to support risk management efforts
and  through  recognition  of   its  research
contributions.  The  recent  Integrated   Risk
Information System (IRIS) evaluation  of the
health   risks  of  inhaled  Libby  amphibole
asbestos is an  example of the  importance of
HHRA program efforts. Libby,  Montana  was
designated a Superfund site in 2002, and in 2009,
EPA determined that conditions in the town
constituted a public  health emergency  with
cleanup required at thousands  of properties.
The  IRIS  assessment  of Libby  amphibole
asbestos involved novel approaches to estimate
cancer risks and it included the first evaluation
of non-cancer effects for asbestos material. The
completion of this  IRIS assessment in 2015 has
provided scientific support to the EPA Office of
Solid Waste and Emergency Response (OSWER)
and Region 8 for the cleanup and related risk
management activities at the Libby Superfund
site.

Other HHRA program  products, such  as the
Integrated Science Assessments (ISA), provide
the scientific basis for setting  the National
Ambient Air Quality Standards (NAAQS), which
arethe most impactful environmental standards
established by EPA. The  ISA for  Particulate
Matter (PM) evaluated thousands of  studies
and was the basis in 2012 for the EPA decision

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to revise the PM NAAQS. The importance of
this scientific assessment is demonstrated by
the estimated net public health and economic
benefits of attaining the revised NAAQS, which
are estimated from $3.7 billion to $9 billion in
2020 (http://www.epa.gov/ttn/ecas/regdata/
RIAs/finalria.pdf).

Rapid  assessment  responses by  the  HHRA
program  for  several recent  emergent
contamination  situations also  supported
swift  and  significant risk management
decisions  that  drew  national  attention. In
January 2014, scientists in the HHRA program
provided input  on the  drinking water health
advisory  issued to address the spill of crude
4-methylcyclohexanemethanol  into  the  Elk
River  in Charleston, WV. HHRA scientists  also
derived an  inhalation screening level, and both
assessments  supported emergency  response
actions  and guided  remediation.  HHRA
scientists also assisted  EPA Region  2  at the
Reich  Farms Superfund  site in Toms  River, NJ.
HHRA scientists developed a  Provisional Peer-
Reviewed Toxicity Value (PPRTV) assessment for
Styrene-Acrylonitrile Trimer and subsequently
participated  in  a  community  meeting on
the  final  risk-based  cleanup  decision  (to
protect both children and adults) based on
the provisional  reference dose. The scientific
foundation for cleanup decisions at more than
1000 National Priority Sites across the country,
and for dozens of drinking water standards and
health advisory levels, has been based  on IRIS
and PPRTV assessments.

Assessment  activities such  as these often
raise critical scientific  issues and stimulate the
advancement of new methods and applications.
HHRA scientists are actively contributing to the
scientific community, as evidenced by the 2015
Best Paper in Toxicological Sciences Award that
they,  together with CSS colleagues, received
for a  joint  publication  on  risk  assessment
from the Society of Toxicology (SOT) Board of
Publications (Thomas et al., 2013).

As illustrated in Figure 1, the HHRA program
plays a pivotal role in the overall ORD research
portfolio  by translating  research  of  other
programs and characterizing its application and
utility  in  assessment  activities.  Additionally,
challenges  encountered   in  the  assessment
activities  of  the  HHRA  program  identify
critical research needs and  help to advance
the development of new applications both by
innovative analyses and methods development
by the HHRA program, as well as by stimulating
the broader scientific community to  conduct
research that supports risk assessment. Often
assessments advance new areas  of scientific
endeavor because challenges of interpretation
and   insights  on  potential   risks   arise  as
research results or new tools are applied and
characterized in context with data on  human
exposure  conditions,  evaluation  of  other
endpoints, and consideration of lifestages and
other susceptibilities.
  Figure 1.  Position of HHRA Program (center red
 oval) with Respect to Overall ORD Research Portfolio
and Agency Risk Management Activities. Information,
  data, and  tools developed in ORD partner research
   programs are incorporated into HHRA assessment
    products and approaches to support risk-based
   decisions (information flow illustrated by left side
 arrows), and insights on their utility or new challenges
 identified in those applications inform new assessment
    approaches and research areas (research needs
          illustrated by right side arrows).

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Problem Statement
Every day, EPA and diverse stakeholders must
make decisions to  protect human health and
the environment from the known or potential
adverse effects of a variety of exposures  to
environmental pollutants. The wide range of risk
management decisions calls for risk assessment
products  and  analytical  approaches  that
tailor assessments  to fit the  purpose of these
various  decisions. Assessment products must
be  scientifically  credible and contemporary
with evolving technologies, whether based  on
very limited data or when integrating evidence
across thousands of sources.
Program Vision
Risk-based decisions by EPA, state/local/tribal
agencies, and the public to protect public health
and  the  environment are based on  reliable,
transparent  and high-quality risk  assessment
methods, models, and data. The HHRA program
supports  this vision by identifying, evaluating,
integrating,  and applying relevant data from
a variety of scientific disciplines to characterize
the risk from exposures of individual chemicals,
chemical mixtures, and mixtures of chemicals
and  non-chemical stressors.  The  assessments
generated by the HHRA program inform  a
variety of risk management decisions, and serve
to identify critical scientific issues and  advance
analytical approaches for their resolution.


Program  Design

The  HHRA  program  is  comprised  of  four
highly  interdependent and  leveraged topics
that  have been  enhanced based  on  partner
and  stakeholder involvement.  In  concert  the
topics  provide  priority assessment products,
identify  critical  issues  as  they  arise,   and
develop or stimulate advances in  approaches
and solutions to address emerging challenges,
incorporate innovations, and continuously refine
applications. The four topic areas, discussed in
more detail below, are as follows and the overall
program structure is represented in Figure 2:

• Integrated Risk Information System (IRIS)
  to  develop  hazard  and   dose-response
  assessments for priority chemicals;

• Integrated Science Assessments (ISAs)
  to characterize the health and environmental
  effects of criteria air pollutants and support
  decisions to retain  or  revise the National
  Ambient Air Quality Standards (NAAQS);

• Community and Site-specific Risk
  to  provide  rapid   response assessments
  and  cumulative  risk methods to  address
  Superfund  site   assessment,   emergency
  response,  sustainability,  and  community
  concerns; and

• Advancing Analyses and Applications
  to  address  science  challenges  affecting
  hazard, exposure or dose-response analyses
  and to  incorporate scientific, technical  and
  communication  innovations  that   improve
  characterization of human and environmental
  impacts  and application of that science to
  address  critical  environmental  protection
  needs.


Building on 2012-2016  Program

ThisStRAP builds  upon and continues to  ad-
vance the HHRA program as outlined in  the
Human Health Risk Assessment Strategic  Re-
search Action  Plan, FY2012-2016. The  2016-
2019  StRAP  responds  to ongoing  review  and
oversight by the  Chemical  Assessment Advi-
sory Committee (CAAC) and the Clean Air  Act
Science Advisory  Committee (CASAC) of  the
Agency Science Advisory Board  (SAB), and  has
been  developed with consideration of recom-
mendations in a January 2015 report of a joint
review provided by the SAB and the Executive

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                    Stakeholder Engagement & Cross-Program Integration
                        Planning / Scoping and Problem Formulation
                          Advancing Analyses and Applications
                      Integrated
                         Risk
                     Information
                       System
                        (IRIS)
 Integrated
   Science
Assessments
    (ISAs)
Community
 and Site-
  Specific
    Risk
                 I
                                            I
                 _[  Stakeholder Engagement & Cross-Program Integration
                             Evaluation / Outreach and Training
  Figure 2. Structure of the Human Health Risk Assessment (HHRA) program. The program design starts
  with problem formulation and scoping with stakeholders and other research programs (denoted in
grey module at top). Development of new methods of analysis and application of these advancements
 into the portfolio of assessment products (IRIS, ISAs, PPRTVs, emergency estimates, etc., indicated
 in the light blue block) results in identification of critical issues that inform and stimulate research
  and new methods development. Evaluation of the  utility of these activities feeds back to problem
    formulation and scoping. Additionally, training  and outreach activities enhance stakeholder
 engagement and builds capacity in risk assessment communities for understanding and  application
                            of new technologies and approaches.
Council of the  Board  of Scientific Counselors
(BOSC) held in July 2014 (U.S. EPA, 2015). The
HHRA program  constantly evolves as its prod-
ucts are assessed for their utility in meeting
Agency needs as new scientific opportunities
arise and as new challenges and  needs are
identified in the risk assessment and manage-
ment arenas. For example, the HHRA program
is developing new assessment approaches and
products based on computational tools devel-
oped via coordination with the CSS research
program. Likewise, emerging technologies such
as sensors will  require guidance on  analytical
considerations,  interpretation, and application
in risk assessment approaches.
        EPA Partner and Stakeholder
        Involvement

        The HHRA program was restructured in 2014 to
        emphasize stakeholder engagement and cross-
        program integration in order to both inform
        the  problem  formulation of  its assessment
        products  and  methods  development work,
        as well as to  provide feedback on the utility
        of the  results  of these efforts to end  users
        as depicted in Figure 2. This initial "up front"
        involvement of stakeholders in the design of
        assessment activities was  recommended by
        the  NRC report Science and Decisions (NRC,
        2009). By implementing the recommendations,

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EPA greatly enhanced stakeholder engagement
throughout  the   IRIS  program   and  was
subsequently recognized by the  NRC  (NRC,
2014).  Such  input  on  problem formulation
and  on  the scope of  activities,  including
prioritization and  pacing, occurs in the  HHRA
program via development and integration of its
projects and tasks with the other ORD research
programs,  and  in collaboration with  HHRA
program partners and stakeholders. In addition,
the program is conducting scientific workshops
to convene experts and stakeholders to discuss
critical  science  issues  and opportunities  in
human health risk assessment. Further, the IRIS
program organizes public science meetings to
support problem formulation and to discuss the
available scientific evidence and issues early in
the assessment development process. Recently,
EPA  arranged with  the  NRC to  identify and
arrange for subject matter experts to contribute
to these meetings, to assure a well-informed
discussion that sets the stage for well-targeted
and efficient assessment  development.

Activities conducted under the HHRA program
are responsive to  the priorities and the  needs
of EPA's  program and  regional  offices (see
Appendix  C for a list of HHRA partners and
stakeholders). The  HHRA  program  conducts
regular meetings  with  its program  partners.
One of   HHRA's   regular planning partner
meetings for two sequential years was devoted
to  development  of  the  HHRA  2016-2019
StRAP with particular focus on two of its topic
areas, Community and  Site-specific  Risk and
Advancing  Analyses  and Applications.  Initial
proposals to address critical science challenges
were discussed at a large planning meeting
with program partners in May 2014,  and then
a revised portfolio of projects and a draft StRAP
were reviewed at  another one in  March 2015.
This  document  represents further refinement
based  on  additional  comments.  The  large-
scale planning meetings are complemented by
regular partner meetings and communications
that occur throughout the year.

Also included in  HHRA outreach  is its  risk
assessment  training  and  experience  (RATE)
program comprised of over 30 specific modules
covering   hazard   identification,   exposure
assessment,    dose-response    assessment,
benchmark  dose  modeling, PBPK  modeling,
mixtures   guidance   and  cumulative   risk
assessment.  These training modules have been
provided internally to EPA program and regional
offices, to various  states, and  internationally.
Further, the  HHRA program has worked with
the  Environmental Council of  the  State's
(ECOS) Interstate Technology and  Regulatory
Council to develop a risk assessment training
program  that targets state   risk  assessors,
increasing capabilities  and consistency in  risk
assessments conducted by federal, state  and
tribal organizations.

The HHRA program components  receive tens
of thousands of webpage views annually by
users, and substantial outreach occurs using
email  listservs. Many  thousands  subscribe to
the HHRA Bulletin and over 500  to the ExpoBox
Bulletin. Thousands more  also subscribe to
receive important updates for the IRIS program
and Benchmark Dose Software (BMDS).

Integration across the Research
Programs

HHRA  integrates   with  the other National
Research Programs through collaboration on its
assessment activities, including incorporation of
research results and by characterization of new
applications  of data and tools. As illustrated in
Figure 3, examples of HHRA program integration
with the other research programs include the
following:

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Impacts of nitrogen
and sulfur oxide
deposition
               Safe and
              Sustainable
                Water
               Resources
                (SSWR)
            Air, Climate
            and Energy
              (ACE)
                                                Support on ISAs
                                                Advancing sensor technologies
Well-being indices
considered in CRA
Community-based CRA
Exposure assessment
and apportionment
              EPA's
        Human Health
       Risk Assessment
       Research Program
            (HHRA)
        Chemical
        Safety for
      Sustainability
         (CSS)
       Computational toxicology
       Applying adverse outcome
       pathways (AOP)
       Dosimetry21: Development and
       update of models for translation
 Sustainable
 and Healthy
 Communities
    (SHC)
V   W
Homeland
 Security
  (HS)
Rapid assessments for
emergency response
Resilience indices considered in
CRA
Figure 3.  Integration of Human Health Risk Assessment (HHRA) research program with other ORD research
 programs. The HHRA program utilizes research and applies tools in its assessment products as well
      as develops assessment approaches and methods to inform needs in the other programs.
  Air, Climate, and Energy (ACE)
  Incorporation of NAAQS research (including
  climate as a welfare effect) and understanding
  multipollutant mode of action into ISAs; IRIS
  assessments of air toxics;

  Chemical Safety for Sustainability (CSS)
  Computational toxicology, applying adverse
  outcome pathways, and dosimetry;

  Homeland Security Research Program
  (HSRP)
  Incorporation of resiliency into cumulative
  risk assessment methods and coordination
  on rapid response assessment;

  Safe and Sustainable Water Resources
  (SSWR)
  Assessment of deposited oxides of nitrogen
  and sulfur on surface water quality; and
                           • Sustainable and Healthy Communities (SHC)
                             Development of Cumulative Risk Assessment
                             (CRA)  methods and  decision analytic soft-
                             ware to provide "place-based" community
                             assessment, link health and ecology impacts
                             to well-being, and support multi-criteria deci-
                             sion assessment (MCDA).

                           The HHRA program  has a specific integration
                           area with the CSS program to characterize the
                           application  and utility  of the tools  and data
                           streams being developed by CSS scientists. This
                           collaboration  is intended to  enhance under-
                           standing of the foundational data and computa-
                           tional  techniques involved in the development
                           of new tools so that they can  be  appropri-
                           ately applied in various risk assessment prod-
                           ucts. Characterizing the utility of these higher
                           throughput data and computational tools  in

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the context of various assessment activities will
facilitate understanding and build  confidence
in their application to  various qualitative and
quantitative  fit-for-purpose risk  assessment
needs, thereby accelerating acceptance of new
approaches by the EPA  program offices and re-
gions as well as external stakeholders. Applying
high-throughput screening (HTS) data  may en-
hance efficiency of rapid assessment for emer-
gency response.  Incorporating mechanistic in-
sights and understanding of adverse  outcome
pathways (AOP) and virtual tissue descriptions
in the CSS program can inform  dose-response
analysis for key events along the spectrum  of
pathogenesis represented  in a  hypothesized
mode of action  (MOA) for a  given  chemical
assessment.  Updating  dosimetry models will
facilitate response analysis and translation  of
diverse data types at various levels of observa-
tion.

The HHRA program also informs critical research
areas  identified  in the   ORD  cross-cutting
Research Roadmaps, as depicted in Table 1.
HHRA  program   products  are  incorporated
across  all of the roadmaps: the ISA projects
are evaluating the  role of criteria  pollutants
on  climate  forcing; evaluation of lifestage
susceptibility and approaches to assessment
are integral to children's health; and cumulative
risk assessment methods form the conceptual
basis for understanding key biological, social,
spatial,  and environmental factors  and  how
they contribute  to  disproportionate risk  of
concern to environmental justice.

HHRA assessment activities are also  integrated
and  coordinated   with   other  interagency
working groups and collaborative relationships
through the  National Center for Environmental
Assessment (NCEA), in which the HHRA program
represents  the  large majority of   resources.
NCEA  currently  has  two   Memoranda  of
Understanding (MOU), one with the Agency for
Toxic Substances and Disease Registry (ATSDR),
and a second with  the National Institute for
Table 1. Human Health Risk Assessment (HHRA) research program contributions to critical needs
identified by ORD roadmaps. The number of checkmarks indicate the relative size of the contribution
of HHRA activities and interest in the identified science gaps of the roadmaps; a blank indicates no
substantive role. As indicated, HHRA is not the lead research program for any of the ORD roadmaps,
but its topic areas provide significant contributions to each of them.
ORD Roadmap
Climate Change
Environmental Justice
Children's Health
Nitrogen & Co-Pollutants
CSS Topic Area
IRIS
Assessments

S
S
V
ISA
Assessments
v'V
S
SS
ss
Community
and Site-
specific Risk
S
V
s

Advancing
Analyses and
Applications

S
S


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Occupational Safety  and Health (NIOSH).
An  additional  MOD with the Food and Drug
Administration  (FDA)  is  nearing  completion.
Close relationships and integration also occur
with international  organizations dealing with
environmental health risks including the World
Health Organization (WHO), the International
Agency for Research on Cancer (IARC) and the
United Nations Environment Programme. NCEA
has  targeted  efforts  through a  cooperative
agreement with WHO to specifically collaborate
on  evaluation  of  priority chemicals   in the
ISA and IRIS programs. Further, NCEA has the
lead role for EPA in  the WHO  Chemical Risk
Assessment Network,  a  cross-organizational
coordinating group including the International
Programme  on Chemical Safety  (http://www.
who.int/ipcs/en/).

Access to data for use in risk assessments is
facilitated by  scientific staff  networks with
other federal  agencies  conducting primary
environmental  health  research,   particularly
at the National Institutes of Health - National
Institute  of  Environmental  Health  Sciences
(NIEHS) and National Toxicology Program (NTP)
and  at the  Centers for Disease Control and
Prevention's National Center for Environmental
Health. The HHRA program also continues to
improve  its  use of information science tools
to improve the efficiency and transparency of
its assessment  activities and  the accessibility
of its scientific resources, including both the
Integrated   Risk  Information  System   (IRIS,
http://www.epa.gov/iris/)   and  the   Health
and  Environmental Research  Online  (HERO)
database (http://hero.epa.gov/).

Research to Support  EPA  Strategic
Plan
In support of EPA's mission to protect human
health  and  the environment,  the Agency's
Strategic Plan identifies five strategic goals and
four cross-agency strategies (Figure 4).
As described in the later section, the accom-
plishments and projected impacts of the HHRA
program address all of the Strategic Goals in the
FY2014-2018 EPA Strategic Plan. These include
Goal 1, "Addressing  Climate Change and Im-
proving Air Quality"; Goal 2, "Protecting Ameri-
ca's Waters"; Goal 3, "Cleaning Up Communities
and Advancing Sustainable Development"; and
Goal 4, "Ensuring the Safety of Chemicals and
Preventing Pollution." The HHRA  program also
supports the cross-agency strategies within this
plan, specifically  "Working  Toward a Sustain-
able Future" and  "Making a Visible Difference
in Communities."
    EPA Strategic Plan (FY2014-2018)
     Goals and Cross-Agency Strategies
 EPA Strategic Goals
 Goal 1: Addressing Climate Change and
        Improving Air Quality
 Goal 2: Protecting America's Waters
 Goal 3: Cleaning Up Communities and
        Advancing Sustainable Development
 Goal 4: Ensuring the Safety of Chemicals and
        Preventing Pollution
 Goal 5: Protecting Human Health and the
        Environment by Enforcing Laws and
        Assuring Compliance
   Working Toward a Sustainable Future
   Working to Make a Visible Difference in
   Communities
   Launching a New Era of State, Tribal, Local,
   and International Partnerships
   Embracing EPA as a High-Performing
   Organize
  Figure 4. FY 2014-2018 EPA Strategic Plan:
      Goals and Cross-Agency Strategies.

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Statutory and Policy Context

As a  regulatory agency,  Congress  authorizes
EPA to write regulations that explain the critical
details necessary to implement environmental
laws.  In  addition,  a number of Presidential
Executive Orders (EOs) play a central role in EPA
activities. A comprehensive list of these laws
and EOs can be found at http://www2.epa.gov/
laws-regulations/laws-and-executive-orders.

A selection of the laws for which  the  HHRA
program  helps to support the EPA's statutory
authority  and  mandates to conduct  work
is shown below. The HHRA program  also  is
responsive to and supports several EOs and EPA
policies. See Appendix B for details.

• The Clean Air Act section 103 mandates that
  EPA conduct a national research and develop-
  ment program for the prevention and con-
  trol of air pollution. The 1990 Amendments
  further require EPA to set National Ambient
  Air Quality Standards (NAAQS) (40 CFR Part
  50)  for criteria pollutants considered harm-
  ful to public health and the environment on
  a  5-year cycle and  mandate the determina-
  tion of risks from mobile, area, and major
  sources of air toxics. The Integrated Science
  Assessments (ISAs) that are developed under
  the HHRA program serve as the basis for deci-
  sions on NAAQS by the Agency's Administra-
  tor.

• The  Safe Drinking Water  Act  authorizes
  research  and assessments focusing on mi-
  crobes   (e.g.,  Cryptosporidium),  disinfec-
  tion byproducts, and other  regulated  and
  unregulated  chemical and radiological con-
  taminants such as arsenic, sulfate, and ra-
  don. The law also mandates that risks are
  quantified for general  and  sensitive  popu-
  lations   (e.g.,  infants,  children,  pregnant
  women)  as   part  of benefit-cost analysis
  when Maximum Contaminant Levels  (MCL)
are established.  Other research provisions
address risks  associated with  waterborne
disease, complex mixtures and  unregulated
contaminants  (e.g.,  development  of  the
Contaminant Candidate List).

The  Comprehensive Environmental Re-
sponse, Compensation, and  Liability Act of
1980, commonly known  as  Superfund, re-
quires  research,  development, and training
to improve EPA's scientific capability to assess
effects and characterize risk to human health
and the environment from hazardous sub-
stances.

The Federal Insecticide, Fungicide, and Ro-
denticide Act provides for federal regulation
of pesticide distribution,  sale, and use. All
pesticides  distributed or sold in the United
States must be registered (licensed)  by EPA.
Before EPA may register a pesticide,  the ap-
plicant must show,  among other things, that
using the  pesticide according to  specifica-
tions "will  not generally cause unreasonable
adverse effects on the environment" typically
characterized by health  and environmental
risk assessments.

The  Resource Conservation and  Recovery
Act gives EPA the authority to control hazard-
ous waste from "cradle to grave," including
the generation,  transportation, treatment,
storage, and  disposal of hazardous waste.
Evaluating  control  technologies   requires
health  and environmental assessments. The
law also sets forth a framework for the man-
agement of non-hazardous solid wastes. The
1986 amendments enabled EPA to address
environmental problems  that could result
from underground  tanks  storing petroleum
and other  hazardous substances.

The Food Quality Protection Act of 1996 re-
quires assessment of risk from exposures to
pesticides,  including  aggregate exposures

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  and  cumulative  risk  and  risk  to sensitive
  subpopulations (e.g., infants and children).

• The Toxic  Substances Control  Act of 1976
  provides  EPA  with  authority  to  require
  reporting,    record-keeping  and  testing
  requirements,  and restrictions  relating  to
  chemical substances and/or mixtures.

Research  Program

Objectives
The three main HHRA program objectives sup-
port the vision of protecting  public health and
the environment  by providing  state-of-the-
science risk assessments; refining risk assess-
ment  approaches  and advancing  innovative
applications;  and  providing  stakeholder  en-
gagement and support by promoting transpar-
ency, efficient access to tools and products, and
training to enhance  understanding and build
capabilities. The three objectives  of the  HHRA
program listed below are mutually informative
and integrated in order to most efficiently iden-
tify, evaluate,  characterize and communicate
science-based solutions to address current and
emerging challenges in human health and envi-
ronmental risk assessment.

Objective 1:  Characterize risks
Efficiently support a range of decision making
with an agile, fit-for-purpose portfolio of robust
and  responsive  assessment products  that
characterize  risks  and potential  impacts  to
human health and the environment.

Objective 2:  Advance and refine assessment
approaches
Refine  risk assessments by identifying critical
issues  and advancing  analytical  approaches
and applications to incorporate new  science,
methods and technologies; and
Objective 3: Enhance and engage
Enhance data access and management systems
to support transparency and efficiency; provide
outreach and engage stakeholders to ensure
support, training,  and tailoring of assessment
priorities and products.

The  following  narratives for  each program
objective  provide  a brief  overview  of  the
objectives and the critical assessment issues
and  key  drivers.  Each  objective  addresses
broad scientific challenges that are intended to
enable EPA scientists to apply  their expertise
and innovation in shaping specific solutions.

Objective 1: Characterize risks
Efficiently support a range of decision making
with an agile, fit-for-purpose portfolio of robust
and  responsive   assessment  products  that
characterizes risks and potential  impacts to
human health and the environment.
The first objective is to continue to provide state-
of-the  science,  peer-reviewed  assessments
and associated technical support activities for
the Integrated  Risk  Information System (IRIS)
used by various program offices, development
of Integrated Science Assessments (ISAs) and
Multipollutant  Science  Documents (MSD)  to
support review of the National Ambient Air
Quality Standards (NAAQS), and  Provisional
Peer-Reviewed    Toxicity    Value    (PPRTV)
assessments for decision making at hazardous
waste sites. The priorities for these products are
described below (see Research Topics section).
Oversight is provided by established standing
scientific committees  such   as  the Agency's
Chemical  Assessment  Advisory  Committee
(CAAC) of the Science Advisory Board (SAB) for
IRIS assessments and the Clean Air Scientific
Advisory Committee (CASAC) of the SAB for the
ISAs.

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The following challenges must be addressed in
orderto meet Objective 1 and sustain the HHRA
program's assessment portfolio representing
the state-of-the science:
Science Challenge 1:  Systematically identify,
evaluate,  integrate,   and  translate   relevant
scientific evidence to assess human health effects
of chemicals for priority Agency decisions;
Science Challenge 2:  Systematically identify,
evaluate,  integrate,  and translate  relevant
scientific evidence to assess human health and
environmental impacts of criteria air pollutants;
and
Science Challenge 3: Provide tools and advance
analyses to help EPA programs and communities
rapidly identify and address risks of  emerging
exposures and prioritize testing.

Objective 2:  Advance and refine assessment
approaches
Refine risk assessments by identifying critical
issues  and advancing analytical approaches
and  applications  to incorporate new science,
methods and technologies.
The  HHRA program is uniquely positioned to
characterize the appropriate  use of new tools
and approaches to risk assessment. The HHRA
product portfolio spanstherangefrom screening
or  prioritization,  across  rapid assessments
for  emergency response  or relatively data-
poor  derivations  in  the PPRTV program,  to
the  evaluation of  highly  sophisticated and
data-rich  studies  and  evidence  integration
for the Integrated Science Assessments (ISA)
supporting the National  Ambient  Air Quality
Standards (NAAQS) as depicted in  Figure 5.
The varying  regulatory requirements relate to
the type and extent of foundational  scientific
evidence, the prognostic capacity of a given tool,
and  the degree of verification  or  confidence
in the application  of  new data or  in a  newly
measured  key event  to serve as a surrogate
versus established  endpoints  and  outcome
measures  in assessments. The  application of
emerging  data  and new biotechnology tools
will be characterized in that context, and their
relative contributions  and  utility may differ
depending on the  specific  assessment arena
- i.e., fitting the application of the new data
to the purpose or problem formulation of the
assessment activity. Objective 2 of the HHRA
program is thus aimed at continuously refining
risk  assessment  approaches  and  advancing
new  analyses  that  incorporate   emerging
technologies to ensure that HHRA assessment
products keep contemporary with the state-of-
the-science.

Critical    issues   identified  through   the
assessment development efforts  that are the
focus of Objective 1 support identification and
prioritization of the  research foci of Objective 2
in the HHRA program. HHRA also avails itself of
advances and strives to address issues that arise
as challenges in the  larger scientific community
in applying emerging biotechnology. The list of
challenges for Objective 2 of the HHRA program
includes the following:

Science Challenge 1: Evaluate and implement
approaches for  systematic review,  evaluation
and  integration  of  evidence, including  factors
affecting  bias,  to   enhance  efficiency  and
accuracy of assessment development including
automated data mining;
Science   Challenge 2:   Broaden   exposure
assessment technology with exposure  factors
for translation of exposure, bioavailability, and
dose estimates (both human and ecological) to
flexibly address different exposure scenarios;
Science Challenge 3: Improve prioritization and
rapid response by evaluating and incorporating
new  data  streams  and  developing  rapid
assessment approaches;
Science Challenge  4: Develop approaches to
incorporate current understanding of key events,
AOP, and  biomarkers to  increase accuracy of
predictions of disease pathogenesis; inform Mode
of Action (MOA); and better characterize critical
endpoints  of relevance to HHRA  (respiratory,
cardiovascular,   neurotoxicity,  developmental,
reproductive toxicity, liver);

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       Science Challenge 5: Update dosimetry model-
       ing approaches to predict a profile of internal
       dose  metrics, including portal-of-entry effects,
       across all  exposure routes  to support use of
       MOA, AOP and aggregate or cumulative risk ap-
       plications;

       Science  Challenge 6: Advance  decision  ana-
       lytic and probabilistic approaches to more fully
       characterize  dose-response functions and un-
       certainty, and thereby better inform benefit-cost
       analyses;

       Science  Challenge 7: Refine  dose-response
       analysis  by characterizing determinants of the
                                          entire spectrum of the response surface includ-
                                          ing concentration, duration, and timing to sup-
                                          port exposure-scenario specific assessment and
                                          consideration of life-stage; and

                                          Science Challenge 8: Expand cumulative risk
                                          assessment methods  to advance "place-based"
                                          community risk  characterizations,   apportion
                                          multimedia exposures and risk to various recep-
                                          tors, incorporate multiple stressors, consider epi-
                                          genetics and susceptibility,  and support multi-
                                          criteria decision analysis and sustainability.
                                         Risk Assessment Application Range
                                         Prioritization and
                                             Screening

                                             EDSP, PMN
                                                   Provisional and
                                                  Reference Values
                                                 PPRTV, PALS, HA, RTR
                                                 RfV, unit risks/CSF, ROD
                                               National
                                              Standards
                                                NAAQS,
                                                  MCL
       .2  o
Regulatory requirements
Evidence consensus
        3
       —  u
          .
       < Q
Degree of Verification
Data specificity
              Predictive Capacity

              Computational Strategy

                  Tools & Data

                   ToxCast

                   AOP & Biomarkers

                   PBPK/BBDR

                   Virtual tissues
Mining / Abstraction '
                                                           Directed Model Structures
                                  Hazard ID
                                                       Dose-response analysis
                                                           Extrapolations

                                                         Multipollutant integration
                                                                 MCDA
  Assessment Acronyms: EDSP = Endocrine disrupter screening program; PMN = premanufacturing notice; PPRTV = Provisional
  peer-reviewed toxicity value; RfV = Reference value (e.g., reference dose); CSF = Cancer slope factor; PALS = Provisional advisory
  levels; RTR = Residual technology review; HA = Health advisory; ROD = Record of decision; NAAQS = National Ambient Air Quality
  Standard; MCL = Maxiumum contaminant level
 Figure 5. Range of application dimensions required across risk assessment landscape varies based on "fit for purpose."
 Figure 5 illustrates the range in critical dimensions for regulatory requirements, scientific evidence, predictive capacity,
     and degree of verification required of applications across the assessment landscape. This ranges from screening
   and prioritization to support of national standards (see insert for assessment acronyms). The type of computational
  strategy employed, such as data mining/abstraction or read-across approaches versus directed model structures (e.g.,
  physiologically-based pharmacokinetic,  PBPK; or biologically-based dose-response,  BBDR; models), also shifts along
 this axis. The domain and role of specific tools and data (illustrated for products of the CSS program) may be different
depending on the assessment context. As an example, adverse outcome pathways (AOP) or biomarkers might both identify
 a hazard or inform mode of action (MOA) considerations for dose-response analyses.  Ultimately, all components can be
incorporated into multi-criteria decision analysis (MCDA) for transparent integration and evaluation of risk and uncertainty.

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Objective 3: Enhance and engage
Enhance data access and management systems
to support transparency and efficiency; provide
outreach and  engage stakeholders to ensure
support, training, and tailoring of assessment
priorities and products.

The  third  objective  of  the  HHRA  program
is  aimed  at  continual  improvements  in
technologies  supporting  efficient assessment
development  and at  outreach  to  improve
understanding of risk assessment issues  and
methods in order to foster development of
institutional capabilities and consistency in risk
assessments developed by various stakeholders.
Further  development   and   improvement
of the  Health and  Environmental  Research
Online (HERO) system  (www.epa.gov/HERO)
supports enhanced assessment  development
and transparency through access to scientific
literature   underlying assessment  products.
                    Software and technical support such as BMDS
                    enables stakeholders  to  apply advances  that
                    the HHRA program develops in dose-response
                    and evidence integration approaches. Outreach
                    efforts can take the form of public workshops,
                    seminars, training sessions as well  as varied
                    communication approaches (e.g., Web posting,
                    emails, and blogs). Challenges in this objective
                    area include the following:

                    Science Challenge 1:  Enhance data access and
                    management systems  to support transparency
                    and efficiency; and

                    Science Challenge 2: Develop and apply effective
                    methods for stakeholder engagement and risk
                    assessment training to varied audiences.

                    An overview summary of the aims in the HHRA
                    research  program,  both  near-  and  longer-
                    term, to  achieve these objectives and address
                    critical science challenges is provided in Table 2.
Table 2. Summary of Near and Long-term HHRA Program Aims to Achieve Objectives and
Address Science Challenges
 Objective
What We Do
Near-term Program
Aim
Long-term Program
Aim
 Characterize risks —
 Efficiently support a
 range of decision making
 with an agile, fit-for-
 purpose portfolio of
 robust and responsive
 assessment products
 that characterize risks
 and potential impacts to
 human health and the
 environment
Tailor risk
assessment products
to meet the range of
assessment needs
in an agile, fit-for-
purposefashion
while maintaining
established
credibility and
scientific quality
and increasing
productivity
Accelerate
completion
of the current
successful array
of risk assessment
products for
priority pollutants
and program
partners while
updating operating
procedures for
evidence integration
and derivation
efficiency;
implement  updating
process for  older IRIS
assessments
Expand assessment
products to ensure
an efficient and
agile portfolio that
addresses critical
areas of assessment
needs, including
characterization
of acute, short-
term and episodic
exposures; integration
of endpoints across
species to support
community concerns
regarding cumulative
risk and sustainability;
and to develop
information to support
benefit-cost analyses
for a larger array of
endpoints

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Objective

Advance and
refine assessment
approaches — Refine
risk assessments by
identifying critical
issues and advancing
analytical approaches
and applications
to incorporate new
science, methods and
technologies









Enhance and engage —
Enhance data access and
management systems
to support transparency
and efficiency; provide
outreach and engage
stakeholders to ensure
support, training, and
tailoring of assessment
priorities and products





What We Do

Characterize and
advance assessment
approaches with
contemporary
and emerging
biotechnology data
and computational
methods












Provide system
infrastructure and
manage access
to assessment
products and data/
knowledge bases to
ensure transparency
and efficiency
while developing
stakeholder
engagement and
building capacity to
support appropriate
implementation of
new approaches
Near-term Program
Aim
Facilitate the
characterization
and application of
new data streams
and emerging
computational tools
by developing and
advancing case study
applications of new
science across the
exposure-dose-
response continuum
for various disease
endpoints; improve
assessment
methods including
systematic review
and approaches to
exposure and dose-
response
Maintain and
expand current risk
assessment tools
and databases to
incorporate new
approaches as they
are developed;
develop and provide
risk assessment
training to EPA
programs and
national and
international
partners

Long-term Program
Aim
Transition risk
assessment
approaches to
incorporate systems
biology understanding
of disease, implement
mature computational
toxicological modeling
approaches, express
risk and uncertainty
probabilistically, and
integrate emerging
sensor technologies







Evolve and upgrade
infrastructure to
create connectivity
and provide
interoperable, modular
computational
capacity to implement
new approaches,
access data sources,
engage stakeholders,
and support training
and communication




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Research  Topics

Three of the four topic areas in  the HHRA
research  program are  devoted to  developing
specialized  assessment products. The fourth
topic is an overarching topic area which informs
all assessments by advancing risk analyses and
applications. The program is highly integrated
and  leveraged.  As shown  in  Figure 6,  nine
project areas are targeted so that those projects
involved  with  assessment activities identify
issues and methods development needs, while
the project  areas  to  advance analyses  and
applications  bring the  state-of-the-science to
                                       maturity  by providing  characterizations  and
                                       building  confidence,  thereby  ensuring  agile
                                       analyses and applications.

                                       The  HHRA  National  Program  Director,  in
                                       consultation  with   ORD   senior  managers,
                                       prioritizes efforts by balancing direct program
                                       support  with   advancement  of  new  risk
                                       methods. The bulk of HHRA resources support
                                       Projects 1 through 5, which provide assessment
                                       products  directly to EPA programs and regions,
                                       thus addressing the program partners' highest
                                       priorities. To maintain the credibility of these
                                       assessments and  increase the  efficiency of
                                       their production, both near- and longer-term
1.

2.
IRIS
Assessments
IRIS Update
3.   Integrated Science
     Assessments and
     Scientific/Regulatory
     Support
5.
                                                    6.
Provisional Peer-reviewed
Toxicity Values
Site-specific and Superfund
regulatory support
Cumulative risk assessment
methods and applications
                    7.   Advancing hazard characterization and dose-response methods
                    8.   Applying emerging science to inform risk screening and assessment
                    9.   Risk assessment support and training

                      Figure 6. The four topic areas and nine projects of the Human  Health Risk
                      Assessment (HHRA) research program.

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commitments  to  Projects 6  through 9  are
required to advance risk assessment methods,
incorporate emerging scientific developments
and   maintain  critical   infrastructure  such
as  databases.  Limited   resources currently
available  to the HHRA program require  the
targeting  of tasks within Projects 6  through
8, which  is accomplished by  considering  the
value and impact of new analyses and methods
on HHRA assessment products, as well as  the
status of complementary research efforts  by
the  other  national programs,  notably  CSS,
which provides input to some tasks in Project
8, and SHC, which collaborates on community-
based approaches. Project 9 advances program
efficiency and transparency (e.g., via the Health
and  Environmental  Research  Online  [HERO]
system),  provides software for use  of  new
approaches in the public domain, and supports
the  Agency  and  external risk  assessment
training   efforts.  HHRA   in-house   staffing,
availability  of  extramural  resources,  Agency
and Congressional direction, and independent
advisory  recommendations (e.g.,  EPA's  SAB
and  BOSC) also  are considered  in decisions
on resource allocation to  HHRA activities. The
following section summarizes key activities and
illustrates anticipated products arising from the
resources committed to the HHRA program.

Topic 1:  Integrated Risk Information
System (IRIS)
Integrated  Risk  Information   System  (IRIS)
assessments developed by HHRA scientists are
peer-reviewed,  qualitative,  and  quantitative
health hazard and dose-response assessments
on environmental pollutants  of relevance to
EPA's mission to protect human health and the
environment   (http://www.epa.gov/iris).   IRIS
assessments are widely used by EPA's programs
and regions, as well as outside of  the Agency
by states,  international organizations  and  the
public, to  support a wide range of decisions.
EPA and the risk assessment/risk management
community consider IRIS the premier source of
health  hazard and  dose-response information
for environmental pollutants.

Project 1: IRIS Assessments
This  HHRA project is devoted to maintaining
the credibility and  responsiveness of the IRIS
program. A strong,  scientifically rigorous IRIS
program is of critical importance, and the HHRA
research  program continues to make changes
that: (1) improve the scientific integrity of IRIS
assessments; (2) improve the productivity  of
the IRIS program; and (3) increase transparency
so that issues are identified and debated early
in the  IRIS process.  In  2009, the IRIS program
announced  a    revised  7-step  assessment
development process shown in Figure 7. Since
that time, the National Research Council made
recommendations  related to improving the
development of IRIS assessments and advancing
risk  assessment  in general,  including the
importance of up-front planning and scoping in
the risk assessment process (NRC, 2011). EPA
is implementing additional changes to the IRIS
program  based on the NRC recommendations
(Appendix  D)  and  an evaluation  of  these
changes has been well received (NRC, 2014).
These changes will help EPA produce more high
quality IRIS assessments each year in a timely
and transparent manner to meet the needs of
the Agency and the public.
                 PROJECT 1 HIGHLIGHTS
                    IRIS Assessments
      IRIS assessments produced with state-of-the
      science to address Agency priorities
      Enhanced production efficiency and stakeholder
      engagement
      Public science meetings
      Problem formulation  opportunities
      IRIS Handbook of Operating Procedures
      to support transparent and tractable methods

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 Identify Pertinent
      Studies
 t
   Evaluate Study
     Methods
    and Quality
Evidence Evaluation
  and Integration
  for Each Effect
 t
 [Select Studies for
  Deriving Toxicity
      Values
   Derive Toxicity
      Values
  Comprehensive Literature
    Search and Data Call-In
Completed lit se
Web and announced in FRN
FRN requesting information about
studies not in lit search and new
research
[ Internal Agency Review
and EPA Clearance of
Final Assessment
EPA-led Interagency
Science Discussion
                                   Science feedback on final
                                   assessment from other Federal
                                   Agencies and White House offices
    Complete Draft IRIS
    Assessment
                                                                Revise Assessment
  Address peer review and public
  comments: prepare response to
  comments document
                                                                         Post Final
                                                                         Assessment on IRIS
                                                                        Includes IRIS surnmaiy.
                                                                        Toxicological Review and
                                                                        response to comments
   Internal Agency Review
 Science Consultation on the
 Draft Assessment with other
 Federal Agencies and White
 House Offices
                         EPA coordinates Interagency review
 'independent Expert Peer
  Review, Public Review and
  Comment, and Public
  Listening Session
 Draft assessment and peer revievj
 charge posted on Web site
 Public comment period and Listening
 Session announced in FRN
 Peer review meeting announced in
 FRN
                Figure 7. Seven steps in assessment development process of IRIS program and work flow of
                                   disciplinary work groups (denoted as green boxes).
      Disciplinary Work Groups
            Work Flow:
      Identify Pertinent Studies
              (Next)
      Evaluate Study Methods
            and Quality
              (Next)
        Evidence Evaluation
          and Integration
           for Each Effect
              (Next)
         Select Studies for
          Deriving Toxicity
              Values
              (Next)
        Derive Toxicity Values
          Assessment Development Process of IRIS program:
          Comprehensive Literature Search and Data Call-in.
          Completed lit searches posted on Web and announced in FRN.
          FRN requesting information about studies not in lit search and new research.
          Step 1: Complete draft IRIS assessment
          Step 2: Internal Agency review
          Step 3: Science consultation on the draft assessment with other federal agencies and White
          House offices. EPA coordinates interagency review.
          Step 4: Independent expert peer review, public review and comment, and public listening
          session. Draft assessment and peer review charge posted on website. Public comment
          period and listening session announced in FRN. Peer review meeting announced in FRN.
          Step 5: Revise Assessment. Address peer review and public comments.  Prepare response
          to comments document.
          Step 6a: Internal Agency review and EPA clearance of final assessment.
          Step 6b: EPA-led interagency science discussion.  Science feedback on final assessment
          from other federal agencies and White House offices.
          Step 7: Post final assessment on IRIS. Includes IRIS summary, toxicological review and
          response to comments.
                              Supplemental Figure 7 formatted to meet Section 508 standards.

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 The formation of disciplinary work groups is
 another enhancement  to the IRIS  program
 that ensures scientific expertise is strategically
 targeted  to  characterize  potential   adverse
 health  effects and endpoints. HHRA  scientific
 experts in these work  groups identify issues
 and advance approaches to address challenges
 specific to their areas. For example, techniques
 are under development for  meta-analysis  of
 epidemiological  studies and  the  use of  AOP
 to help elucidate windows  of  susceptibility
 for developmental  effects. The  IRIS  program
 is  also  developing a  Handbook  of Operating
 Procedures  to   provide   transparency  and
 enhance understanding  of IRIS assessments  by
 Agency partners and external stakeholders.

 Project 2: IRIS Update
 This  project  will update the  existing  IRIS
 database and  implement  plans  to  maintain
 its currency. During the  past two decades, the
 IRIS program has focused  on a relatively small
 number of  scientifically  complex, resource-
 intensive assessments.  This has left the rest
 of the  IRIS database untouched, to the point
 that today, more than 80% of the hundreds of
 IRIS assessments are more than  20 years old.
 Even recent  assessments can become  out-
 of-date as new  studies  become available and
 scientists understand more about the many
 ways  chemicals  can  affect   human health.
 This  situation is not unique  to  IRIS,  rather,
 it  is  common to human  health assessment
 programs worldwide.
   PROJECT 2 HIGHLIGHTS
         IRIS Update
Process to prioritize and update
IRIS assessments
Streamlined approach to update
older assessments
EPA  remains  committed  to  continue  to
strengthen  the  IRIS program and increase
transparency   and   productivity.   The  IRIS
program  has developed a multi-year agenda,
which provides information about the status of
active assessments and  highlights assessments
scheduled to begin in  the future (www.epa.
gov/IRIS). The program  is working to improve
the IRIS database including an effort to evaluate
chemical  assessment needs  both  within and
outside of EPA and the resources  required  to
meet  those needs. Further, the  program  is
developing  a process to update and maintain
finalized IRIS assessments that do not warrant a
full reassessment through the IRIS process.


Topic 2:  Integrated Science
Assessments  (ISAs)

The HHRA  program  regularly  develops ISAs
(formerly Air Quality Criteria Documents)  as
a major component  of its research portfolio
(http://www.epa.gov/ncea/isa/).   The   ISAs
are developed on a 5-year cycle in response
to regulatory requirements  and  provide the
scientific  basis  for the  EPA Administrator's
decisions on  setting NAAQS for the criteria
pollutants  (particulate  matter,  ozone,   lead,
carbon monoxide, and sulfur and nitrogen
oxides) that are ubiquitous  in ambient air
due to numerous and diverse  mobile and
stationary sources. Attainment of the NAAQS
for these pollutants has been estimated by the
Office of  Management and Budget (OMB) and
EPA to provide significant public  health and
environmental benefits to the American  public
that far exceed the cost of control programs.
The direct benefits of EPA's air programs include
the reduced incidence of a number of adverse
human health impacts, including  premature
death and disease, improvements in visibility
and avoided damage to trees, agricultural crops
and other vegetation.

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     In  planning  and  developing ISAs,  the HHRA
     program works in very close collaboration with
     the primary client office, the Office of Air and
     Radiation's (OAR) Office of Air Quality Planning
     and Standards (OAQPS), as well as the Clean
     Air  Scientific  Advisory  Committee  (CASAC)
     and other stakeholders as  shown  in Figure 8.
     ORD's Air, Climate, and Energy (ACE)  research
     program conducts intramural laboratory-based
     research  and  extramural   research  through
     the Science to Achieve Results (STAR) grants
     program  in support of  ISA development. The
     ISAs   incorporate  and  synthesize   research
     findings from the ACE research program and
     others into the assessment documents. Early
     in the development process, HHRA convenes a
                             workshop with the client office and the scientific
                             community to identify the most policy-relevant
                             science issues. A draft  integrated review plan
                             for each ISA is then developed that includes the
                             ISA which is the responsibility of HHRA, and the
                             complementary Risk and Exposure Assessment,
                             if  warranted, and a  Policy Assessment, both
                             of which  are the  responsibility of OAQPS.  All
                             external review drafts of these complementary
                             assessment products undergo public comment
                             and  rigorous peer review  by the  CASAC.  In
                             addition, draft ISAs are reviewed internally and
                             through workshops covering specific scientific
                             areas of the assessment.
   Workshop on
science-policy issues
Integrated Review Plan (IRP): timeline and key
 policy-relevant issues and scientific questions
                                Integrated Science Assessment (ISA): evaluation and
                                      synthesis of most policy-relevant studies
                                        Risk/Exposure Assessment (REA):
                                    quantitative assessment, as warranted, focused
                                    on key results, observations, and uncertainties
                                          Policy Assessment (PA): staff analysis of
                                            policy options based on integration and
                                         interpretation of information in the ISA and REA
                       Public hearings
                       and comments
                         on proposal
                                                       Agency decision
                                                       making and draft
                                                        proposal notice
                   Agency decision
                   making and draft
                      final notice
                                                             Clean Air Scientific
                                                            Advisory Committee
                                                              (CASAC) review
                                                              Public comment
                  Figure 8. Development process and role of Integrated Science Assessments
                  in support of decisions to retain or revise the National Ambient Air Quality
                                  Standards for the criteria air pollutants.

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Project 3: Integrated Science Assessments
and Science/Regulatory Support

Tasks in this project support these efforts
of planning,  developing  the ISAs, providing
regulatory support regarding their implementa-
tion, and advance specific scientific approaches
and solutions to issues that arise.  In this next
FY2016-2019  period, the HHRA program ex-
pects to be supporting ISA and regulatory sup-
port to the Office of Air and Radiation  (OAR)
regarding the final promulgation on the SO2 pri-
mary (health) and NO2 primary (health) NAAQS
in FY18 and the secondary (welfare) NAAQS in
2019 for SO2and NO2, while also initiating de-
velopment of the ISA for PM. Support to OAR
regarding  implementation of ISA to policy as-
sessment and rulemaking for decisions regard-
ing review, retention, or revision of the NAAQS
will also be provided for these same pollutants.
A more detailed schedule of ISA activities can
be found in Appendix A.

The  evaluation  of  data and development of
these ISAs often identify issues that the  HHRA
program  endeavors to resolve. For example,
recognizing that individuals  are not exposed
to a single pollutant in isolation but rather to
a complex mixture  of air pollution, HHRA and
ACE scientists have planned to work in consul-
tation with EPA offices to  develop  multipollut-
ant science documents (MSD) to support the
reviews of the primary (health-based) and sec-
ondary (welfare-based) NAAQS. These MSD are
intended to aid in evaluation of the combined
health effects of the exposures to  mixtures of
air pollutants, as well as providing a more ef-
fective evaluation of health effects of exposures
to single pollutants in a multipollutant context
than what is currently provided  using  single
pollutant  ISAs.  Such understanding  supports
strategic roadmaps regarding climate, address-
es environmental justice  (EJ) issues,  informs
understanding of MOA for respiratory effects,
and advances cumulative risk-characterization
methods. At present, budget constraints have
delayed development of MSDs but, as resourc-
es permit, the development of these assess-
ments will proceed.

Science advancements also derive from the ISA
assessment activities such as  an approach to
the determination of causality for the toxicity
of lead (Pb) used coherence of the MOA across
human and ecological species (Lassiter et al.,
2015).  Additional advancements on applying
insights from data evaluations in support of the
other ISAs are anticipated.
         PROJECT 3 HIGHLIGHTS
     ISA Assessments and Scientific/
           Regulatory Support
    ISA assessments for S02, N02, PM and
    NOX/SOX ecological effects
    Regulatory support  to OAR regarding
    rule development and risk/exposure/
    policy assessment
    Advances in application of new science
    to characterize critical effects and
    interactions of criteria pollutants
Topic 3: Community and Site-Specific
Analyses
Significant progress in environmental protection
has occurred in the United States  over  the
past decades, but many challenges remain,
and some communities are disproportionately
impacted. While many environmental  problems
are global, national and  regional in nature,
their impacts are experienced most acutely at
the community level. For  example, every day,
communities face challenges with management
of municipal and hazardous waste. The  HHRA

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program  directly supports risk management
decisions  related  to  waste  sites  through
development of  Provisional  Peer  Reviewed
Toxicity Value (PPRTV) assessments.

Project 4: PPRTV Assessments

PPRTV assessments  provide toxicity  values
derived for use in EPA'sSuperfund program when
a value is not available in the IRIS database. The
PPRTV assessments are used by the Superfund
program  and regional  decision  makers when
making site-specific cleanup decisions, such as
when to  pursue monitoring for a contaminant
of concern. The implications of these decisions
include improvements in  human health in the
vicinity of Superfund sites, reduction or reversal
of damages to  natural resources,  reduction
of harm  in emergency situations,  improved
economic conditions and  quality of  life in
communities affected by hazardous waste sites,
improved environmental practices by industry,
and advances in science and technology.
          PROJECT 4 HIGHLIGHTS
           PPRTV Assessments
    > 12 assessments annually to support
    OSWER regulatory decisions
    Implementation of improvements in
    systematic review and application of
    other analysis advances as they
    become available
    Application of new data streams and
    computational methods as utility is
    characterized by case studies
Priorities for PPRTV development are based
on the needs of the Office of Solid Waste and
Emergency Response (OSWER) and evaluated
annually.  PPRTV   assessments  are  derived
following  a  review of the relevant scientific
literature using the same methods, sources of
data, and  guidance on dose-response analysis
used by the IRIS program.  All PPRTVs receive
internal review by a panel of EPA scientists and
external peer review  by independent scientific
experts and  are  publicly available  (http://
hhpprtv.ornl.gov). Applying new data streams,
read-across  approaches,   and computational
tools   to   enhance   the   supporting   data/
knowledge bases and efficiency of derivation
for PPRTV values is an active area of research in
the HHRA program.

Project 5: Site-specific and Superfund
Technical Support

Communities are  also faced  with an urgent
need  for coordinated assistance to assess
and  address  issues  of chemical and  other
environmental contamination, and additionally
are  now  presented  with new  sensing  or
monitoring  information  that is  difficult  to
interpret.  EPA's  HHRA program is frequently
called upon to quickly assist in these situations,
often in the face of large scientific uncertainties
due to data gaps.  Project 5 is structured with
tasks to address these needs.

EPA  provides  rapid   risk assessment   and
technical consultation  regarding both health
and ecological impacts through five technical
support centers, two  of which are supported
by  the   HHRA   program:   the   Superfund
Technical  Support  Center and the  Ecological
Risk Assessment Support  Center1. The  HHRA
program provides such support directly to the
Homeland Security research program as the lead
for the Agency on emergency contamination
situations.   The   HHRA   program  develops
approaches  to respond  to these emerging,
often  crisis-level,  chemical/substance  issues
'The other three technical support centers, the Ground Water Technical Support Center, the Engineering Technical
Support Center, and the Site Characterization and Monitoring Technical Support Center, are supported by ORD's
Sustainable and Health Communities (SHC) research program.

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with sound science that allows for quick action
and, ultimately, quick decisions and effective
solutions.   The  HHRA  program  anticipates
developing new assessment approaches  by
means of an expanded product line to enhance
rapid response and screening capabilities and
to augment toxicity value derivation procedures
for health assessments.
          PROJECT 5 HIGHLIGHTS
        Site-specific and Superfund
             Technical Support
      Quarterly reports on support
      provided via the technical support
      centers
      Rapid assessment support to
      emergent situations
      Special assessment assignments as
      novel Agency priorities arise
      New assessment products to rapidly
      predict risk
Project 6: Cumulative Risk Assessment
Methods and Applications

To  address  the  desire by  communities  to
understand  and  conduct  local  or  "place-
based"  assessments,  another major  project
area of research under this topic is expanding
cumulative risk  assessment  (CRA)  methods,
developed to integrate and evaluate impacts
of chemical and non-chemical  stressors on the
environment and health, as shown in  Figure
9.  Current  CRA  activities includes strategic
coordination and science support to the EPA's
Risk Assessment  Forum  Technical  Panel  on
CRA (http://www.epa.gov/raf/) and providing
training on CRA methods.

Understanding the various key biological, so-
cial, spatial, and environmental factors and
how they contribute to disproportionate risk
will facilitate support on environmental justice
and faster application to communities. Specific
analyses  and case studies are anticipated to
continue  and will advance approaches useful to
both qualitative and quantitative consideration
of cumulative risks (Gallagher et  al., 2015).
Analyses  will  look at specific interactions, in-
cluding PM and decreased heart  rate variabil-
ity, access to green space with asthma and al-
lergy occurrences, and psychosocial stress with
chemicals that alter the hypothalamic pituitary
adrenal (HPA) axis. Other case studies may in-
clude scenario-specific studies in collaboration
with regional partners. A new task is devoted
to consideration of approaches to incorporate
susceptibility and the role of epigenetics. Evalu-
ation  of  exposure modeling  and  guidance on
how to apportion exposure and risk of mixtures
to phthalates and to both human and ecological
receptors in various media is another task an-
ticipated  to help advance application of cumu-
lative risk assessment. A forthcoming vision pa-
per will provide recommendations to advance
CRA to  include  ecological  assessment using
multi-criteria decision analysis (MCDA) to sup-
port transparency in valuation. Another case-
study will explore implementation of a model
that explores factors influencing sustainability.
           PROJECT 6 HIGHLIGHTS
 Cumulative Risk Assessment (CRA) Methods
 • Advance cumulative risk methods to
  characterize interactions of chemical and
  non-chemical stressors
 - Scenario-specific case studies to explore
  CRA implementation
 ~> Development of approaches for the integration
  of ecological and human endpoints using
  multi-criteria decision analysis (MCDA)
  Consideration of susceptibility and
  epigenetics
  Evaluation  of exposure and risk apportionment
  across media

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     Future work with the HSRP and SHC programs
     is  expected  to   consider  how  to  integrate
     resiliency   and   well-being   indices   under
     development in those programs into the CRA
     framework. Research and work supporting CRA
     is central to advancing the EPA Risk Assessment
              Forum's CRA Guidelines, and will  position the
              HHRA program to better address place-based
              assessments activities and  thereby  support
              sustainability, climate, and goals articulated in
              the Environmental Justice roadmap.
   Byproducts (Showering)

£
Jr
Emissions,
jr Disinfection

Sources of Toxicants

i


Soil/Sediments
Source Water,
Combustor Deposition


]
Ingested S
Local
Drinkim
              Overall Level of
                Vulnerability
Vulnerability Factors / Buffers

• Access to health care

• Crime rates

• Proximity of homes to
 pollutant sources

• Socio-economic status

• Diet/nutrition

• Access to recreational facilities

• Social support networks
         Environmental
           Stressors
                    Physiological
                     Background
Biological & Genetic
 Traits/Sensitivities

• Population illnesses
 (e.g., asthmatics,
 diabetics)

• Genetic predisposition
 to contracting a
 disease (e.g. breast
 cancer)

• Intrinsic traits (e.g.,
 race, gender)
Cultural. Dietary and Behavioral Factors

• Local fish as staple of diet

• Smoking, drug/alcohol abuse

• Outdoor activities highly valued

• Drinking water from privately owned wells
                  Figure 9. CRA framework illustrating various potential roles of chemical and
                 non-chemical Stressors and buffers. Current areas of emphasis in  HHRA are
               interaction of ecological and human Stressors, and active collaboration with the
                  HSRP and SHC programs to consider resiliency and well-being indices.

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Topic 4:  Advancing Analyses and
Applications

The  HHRA program  is  multidisciplinary and
aimed at incorporating scientific innovations to
advance analytic approaches and applications.
Projects  under  this topic  are  targeted  at
enhancing hazard characterization, expanding
the  repertoire  of  dose-response  methods
and  models,  and characterizing the  utility
of emerging  data  and  new  computational
tools as applied to  risk assessment. Another
project  enhances  and  maintains  databases
and software support to ensure transparency,
and facilitates understanding and translation
to Agency partners and external stakeholders.
These projects are critical to keeping assessment
activities contemporary with emerging concepts
in exposure sciences, advances in biotechnology,
and the evolution of computational approaches
and systems biology for understanding disease
processes and ecosystem impacts. Refinements
to current approaches are expected to improve
the accuracy, efficiency, flexibility, and  utility
of applications across the large landscape of
assessment  activities  served  by the  HHRA
program and position it to be more agile and to
better support characterization of wellness and
sustainability.

Project 7: Advancing Hazard Characterization
and Dose-Response Methods

Tasks in this project advance new approaches
and refine procedures to address specific chal-
lenges that arise across HHRA assessment ac-
tivities. Systematic review methods were rec-
ommended by the NRC (NRC,  2011) and aid
transparency  of  assessment  activities and  in-
form evidence integration for determination
of hazard.  Steps include identifying relevant
studies and  evaluating  their quality, identify-
ing relevant endpoints for human health risk
evaluation, evaluating mechanistic information,
synthesizing study results within an evidence
stream for a health effect (e.g., human, ani-
mal, mechanistic),  and integrating  qualitative
and quantitative information across evidence
streams. A task on advancing systematic review
will continue to evaluate case studies,  incor-
porate feedback from  workshops  conducted
with stakeholders,  and compare available ap-
proaches in  order to develop tailored tools to
HHRA assessment products. This work will re-
sult in consistent and transparent approaches
for systematic review across HHRA assessment
products.
             PROJECT 7 HIGHLIGHTS
     Advancing Hazard Characterization and
             Dose-Response Methods
   Advancing systematic review methods
   Case studies to apply AOP and MO A to inform
   hazard characterization and dose-response
   Expansion of dose-response models
   Approaches to benefit-cost and uncertainty
   analyses
   Characterizing determinants of risk to support
   assessment of acute, short-term and episodic
   exposures
   Workshops on critical challenges
Assessment  activities  have  also  identified
more powerful statistical methods for dose-
response and trend analysis that may improve
quantification.  More  robust methods such as
Bayesian approaches and  model  averaging
for  uncertainty  analyses may also  improve
quantitative  approaches  and  ensure better
coverage of  response. These methods will be
evaluated with  case studies and code developed
to support subsequent implementation.

The HHRA program anticipates that  in order to
advance  and achieve the vision proposed by
the NRC for exposure science  and  toxicology
testing,  these  concepts must  be  applied in
risk assessment approaches. As understanding

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of  systems  biology  advances,   mechanistic
insights  should  help  to  incorporate  other
measures  such as  biomarkers  and  effects at
different levels of biological organization into
risk assessment for a fuller characterization of
the spectrum  of  a disease outcome and the
key events of pathogenesis. For example, how
do new data mining tools for in vitro measures
at the  genomic level inform  dose-response?
As our understanding  of the  key events for
different   endpoints   or   diseases  evolves,
building bridges to systems  biology requires
                                    construction of methods that can incorporate
                                    data  on   biomarkers  from  various  disease
                                    dimensions (e.g., early or late-stage) in various
                                    tissues (e.g., blood or liver) of different species,
                                    and the ability to incorporate high-throughput
                                    data  and  adverse  outcome  pathways (AOP)
                                    with  different  degrees of verification.  The
                                    prognostic  significance of  various key  events
                                    relative  to  more  traditional  endpoints  and
                                    disease  outcomes  needs   to  be  established
                                    to employ AOP and MOA in risk assessment.
                                    Figure 10  provides a conceptual construct of
  Exposure
                             Biologically
                              Effective
                               Dose
                                Early
                              Biological
                                Effect
 Altered
Structure /
 Function
         Exposure
      Exposure Factors

                                                                        Effect
    Prognostic
   Significance
  Exposure
 Receptor
Concentration
Dosimetry _' DF1 • '
** n^— *" -|- x


^
>
j



Molecular J'
Initiating Event i^^
(MIE)
^ ^^^^^.
DF2 DF3
Gene Activation 1
Protein Production ^
Altered Signaling •



Altered
physiology
(Disrupted
homeostasis
Altered tissue
development/function
^r ^
H Ad verse
Outcome

^
\ J
¥

/
                             Human
                            Health Risk


                                               'i   ^ -- .
                                        Susceptibility
  Figure 10. Conceptual construct showing the relationships of computational models and schematics
  developed for biomarkers, AOP and MOA applied to risk assessment. The scheme of key events along
  the exposure-dose-response continuum is based on that of Schulte (1989) as proposed for biomarkers and
  modified by Jarabek et al. (2009) for mode of action (MOA). The blue box and blue-bordered key events
  outline elements of an adverse outcome pathway (AOP) described by Villeneuve et al. (2014). Key events
  of pathogenesis are depicted as solid border nodes, key event relationships are depicted as solid directed
  arrows between key events,  and determining factors (DF) that control or may modify those  relationships (e.g.,
  ventilation rate; absorption, distribution, metabolism or elimination; repair, etc.) are depicted as dashed ovals
  and arrows. The areas covered by components of a biologically based dose-response (BBDR) model structure to
  support quantitative dose-response analysis are shown as the following:  exposure models (green); dosimetry or
  physiologically based pharmacokinetic (PBPK) models of toxicokinetics (TK) to describe tissue delivery (orange);
  and tissue response or toxicodynamics (TD) models (pink). Markers or considerations of susceptibility inform all
  components of the continuum. For example, lifestage or  disease state factors may influence parameter values
  for exposure, dose, and response.

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the  relationships  among  biomarkers,  AOP,
and MOA, the types of computational models
that  can  inform  and improve the  accuracy
of descriptions for those  relationships,  and
where considerations of  susceptibility  (e.g.,
due to lifestage or disease) may modify those
relationships.  Several   applications  of  this
knowledge are applied in tasks under Project 7.

Afuller characterization of disease pathogenesis
also   necessitates   consideration   of   the
nature of toxicity and how this relates to the
various  exposure scenarios that may require
assessment.  Real-world  exposures  include
single acute  duration increases in exposure
and fluctuations in  exposure levels (including
repeated episodic increases). To best address
these variables, accumulation  of  effects  or
the  chemical  must  be  characterized,  and
consideration given to susceptible life stages
or windows of vulnerability. Determinants such
as the concentration,  duration, and timing  of
exposures for different  classes of  chemicals
based on physicochemical characteristics (e.g.,
aldehydes versus volatile  organic  chemicals)
and specific endpoints of interest across HHRA
risk assessment products will be evaluated  by
targeted case studies aimed at developing new
assessment products to characterize risks from
various exposures.

Benefit-cost analysis  is  widely employed  in
evaluating environmental policies, enjoys wide-
spread acceptance, and is required by Executive
Order and certain statutes. Case studies will  be
used to  explore extension of methods to quali-
tatively and quantitatively address benefit-cost
and uncertainty analyses through review of lit-
erature, evaluation  of available methods, and
use and possible  development  of software.
These will be targeted at critical disease out-
come and effect measures of interest to partner
program offices.

Other specific issues  arise in  various assess-
ment activities or  as emerging science  and
understanding evolve.  For  example, the IRIS
assessment for inhaled methanol required de-
velopment of methods to address endogenous
background levels. The HHRA program devotes
special workshops to discuss and evaluate spe-
cific  issues as they  arise in assessments with
the broader  scientific community  and stake-
holders. These workshops not only inform the
specific assessments, but also enhance under-
standing and  appreciation of current scientific
challenges and thereby stimulate new research
and methods to accelerate their application in
assessments.  As examples, past  and near-term
planned workshops to  be  convened by the
HHRA program are devoted to the following is-
sues:

• Mode of action for development of mouse
  lung tumors (2014)

• Workshop on systematic review methods
  (2014)

• Epigenetics workshop (September 2015)

• Advancing systematic review
  (December  2015)

• Temporal issues for environmental
  pollutants: Health effects and methodologies
  for estimating risk (January 2016)

• Characterizing and communicating
  uncertainty in human health risk assessment
  (2016)

Project 8: Applying Emerging Science to
Inform Risk Screening and Assessment

This  project  is devoted to characterizing the
utility of new data streams and  computational
tools, such as those  developed by the CSS
program and  increasingly available  from other
sources such as the NIH, university consortiums,
and  the  clinical  arena.  The  HHRA program
plans to approach this characterization of high-
throughput screening  and other data mining

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outputs as applied to informing and improving
HHRA risk assessment products in a step-wise
fashion. Emergingdatastreamswill beevaluated
in the exposure-dose-response context of risk
assessment in order to  understand what key
biological, spatial, or temporal features the new
measures or computational tool may represent
(Figure 10). This  understanding is the basis for
building confidence in and building capacity for
employing emerging technologies across the
assessment landscape spanning from research
prioritization to risk screening, and ultimately
quantitative dose-response analysis (Figure 5).

The HHRA program will approach the imple-
mentation of these new data and tools both
from the perspective represented by under-
standing the significance of molecular initiating
events (MIE) for chemicals with different physi-
cochemical properties and associated with po-
tential  AOP for predicting specific endpoints;
as well as from the perspective of developing
approaches for integrating these data and end-
points to describe different diseases. These are
viewed  as  complementary approaches that
evaluate evidence along the same continuum
of potential disease pathogenesis.

The utility to  characterize risk of various data
from  alternative, high-throughput screening
(HTS) platforms or approaches such as structural
read-across/quantitative structure-activity
relationship (QSAR), in vitro biological activity
assays   (e.g.,  ToxCast),  and  toxicogenomics
will  be  evaluated  for  different classes  of
chemicals and  various  endpoints commonly
encountered  in  risk assessment.  These case
study characterizations  should  support  the
development  of new assessment products and
refined approaches to derivation of PPRTV and
IRIS assessments.

Development of a disease-based  data integra-
tion approach will begin with case studies of
specific  disease outcomes of interest to HHRA
assessment priorities, such as that underway
for inorganic  arsenic. The  approach will  build
on lessons learned in the report Next Genera-
tion Risk Assessment:  Incorporation of Recent
Advances  in  Molecular,  Computational,  and
Systems Biology (U.S.  EPA, 2014). This report
was a collaborative effort by the CSS and HHRA
programs and points to future directions for
stronger collaboration and innovative applica-
tions of new  data streams and computational
approaches in risk assessment. Collaboration
with the CSS program for developing  screen-
ing and read-across applications is ensured by
having HHRA scientists participate on the Dem-
onstration and  Evaluation  project within CSS;
these same scientists are involved in tasks that
then apply the tools developed directly into in-
forming PPRTV  assessments or for developing
new assessment products.
             PROJECT 8 HIGHLIGHTS
      Applying Emerging Science to Inform
         Risk Screening and Assessment

   Characterizing utility of new data streams and
   computational tools applied to risk assessment
   products
   Case study exploration of disease-based data
   integration approaches
   Updated dosimetry models and guidance to
   support the application of AOP key events and
   MOA in dose-response analyses
   Expanded exposure assessment tools and
   guidance
   Analytical considerations and interpretation
   guidance for selected emerging sensor data
Another task is devoted to revising dosimetry
adjustments to address  multiscale integration
of data in  order to  advance the application
of  AOP/MOA  or  biomarker  data.  Current
models and guidance on choice of dosimetry
models will be updated to describe potential
dose metrics for key  events at different levels

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of organization for portal-of-entry  effects  in
the respiratory tract and other critical target
tissues. These updates are necessary to inform
both evidence integration approaches and  to
facilitate  quantitative  dose-response analyses
in keeping with the NRC vision represented  by
Exposure21 and Tox21 recommendations (NRC
2007; 2011). This task and others on exposure
will also  evaluate how best to integrate with
exposure modeling platforms.

Exposure assessment is also a key component
integral to characterizing hazard and risk and
an area of rapidly emerging scientific advances.
There is broad recognition thatthe risk estimates
used to protect human health and ecosystems
would be improved with better exposure data
(NRC, 2012). With the recent development  of
large  environmental and chemical databases
and personal and environmental sensors, there
is  great opportunity to improve methods  to
more accurately  characterize exposure  (e.g.,
intensity,  frequency,  duration,  and  route).
However, to utilize the diverse array of newly
available   data  for exposure  assessments,
methods  are required to translate and adapt
data into well-established exposure  protocols.
A  task in Project 8 on the evaluation  and
application of new exposure data and methods
is targeted to do so.

EPA's  EXPOsure toolBOX (EPA-Expo-Box)  is a
toolbox  created by HHRA scientists to assist
individuals from within government, industry,
academia, and the general public with assessing
exposure. It is a  compendium  of exposure
assessment  tools  that  links  to  guidance
documents,  databases,  models,   reference
materials, and other related resources. Exposure
assessment resources are organized into six Tool
Sets, each containing a series of modules that
can be accessed from the link below. In addition,
links to resources on other over-arching topics
can be accessed from the Quick Finder menu at
the top of the homepage. EPA -Expo-Box also
contains an Exposure Factors module which has
been designed to improve the accessibility and
usability  of data from EPA's Exposure Factors
Handbook: 2011 Edition (U.S.  EPA, 2011). EPA-
Expo-Box  is available at  http://epa.gov/risk/
expobox/. Work in this  task will update EPA-
Expo-Box  and  exposure factors  data  as new
and improved tools and data become available.
HHRA  scientists will also develop new tools
for accessing and updating data on ingestion
factors and collaborate with the  SHC research
program  to consider potential approaches for
collecting soil and dust ingestion data.

Other  new products under this task include
development of the Exposure Factors Interactive
Resource for Scenarios  Tool  (ExpoFIRST) and
EPA-Eco-Box.  ExpoFIRST is a  standalone tool
that  draws from data  in  the EPA's Exposure
Factors Handbook for quick, easy, and flexible
development of human exposure  scenarios.
EPA-Eco-Box is being developed as a Web-based
toolbox providing links to guidance documents,
databases, and other relevant information for
ecological risk assessors.

Another  product in this task  represents a
joint venture with the  National Institute for
Occupational Safety and  Health (NIOSH) Center
for Direct Reading  and Sensor  Technologies.
The   analytical  considerations   underlying
specific sensors and their interpretation will be
a continued collaboration with other research
programs  employing    such   technologies
including ACE, HSRP, and SSWR. Considerations
for analytical characterization  and guidance on
interpretation of sensor data in risk assessment
will be developed.

Project 9: Risk Assessment Support and
Training
By  providing   high-quality  targeted   tools,
data, and training,  EPA enables consistency in
assessmentapproaches by various stakeholders,
enhancing the quality of assessment products

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and confidence in risk-based decision  making.
Stakeholder engagement regarding the output
of the HHRA program is enhanced by training
on  risk  assessment  methods  and outreach
regarding  risk  assessment  activities  and
applications. Feedback on the utility of various
assessments, including their scope and content,
cycles back to  the problem  formulation input
for the program in the future.

Tasks under this project involve  updating and
maintenance of critical software  infrastructure
with enhanced features including data access,
interoperability with  other  ORD models and
databases, and transparency of assessments,
such as the Health and Environmental Research
Online (HERO)  database (http://hero.epa.gov/)
of studies used in assessments and benchmark
dose  software  (BMDS)  for dose-response
modeling  (http://www.epa.gov/ncea/bmds/).
New software modules to support advances in
evidence integration and extend dose-response
methods will be developed. Training modules
on  new tools  are also included to  inform
the risk assessment  community of  methods
and advances in risk  analysis, and to  support
consistency in risk assessment development.

One example of training that HHRA scientists
have developed is a program  entitled  Risk
Assessment Training and Experience (RATE), a
comprehensive set of risk assessment training
modules in the four  primary areas of hazard
identification,   dose-response   assessments,
exposure assessment, and risk characterization
for both human health  and ecological risk
assessment.  Additional  areas  of  focus  for
guidance and  training are risk  management,
risk communication, and new approaches  in
human health  risk assessment  methodology.
Risk assessment training sessions  using the
RATE  materials have been  used in multiple
national and international training efforts and
support  many  of the ORD research programs
by broadening the knowledge base of involved
staff. The HHRA program will continue to support
this training as  an important resource for its
program partners and external stakeholders.
          PROJECT 9 HIGHLIGHTS
       Risk Assessment Support and
                 Training
      Updating and maintenance
      of HERO database and BMDS to
      support assessment activities and
      stakeholder engagement
      Enhanced features for
      interoperability and data access
      New modules to support advances
      in evidence integration and dose-
      response analyses
      Training to support understanding
      and consistency of risk assessment
      development

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Anticipated Research

Accomplishments

The  HHRA  program  has  developed  nine
integrated project areas to provide  a program
structure that emphasizes efficient assessment
development  while advancing  needed  risk
assessment-related  analyses  and applications.
During   the   development   of   chemical
assessments, cross-cutting issues may arise, and
their resolution leads to advances in the state-
of-the-science, as well as advancing  knowledge
and consistent use of methods and  models by
the risk  assessment  community. Anticipated
accomplishments under these  project areas
are briefly listed below and selected proposed
outputs  are  presented  in  table  format in
Appendix A.  These HHRA program activities
also inform the four ORD roadmaps (Climate
Change,  Children's  Environmental   Health,
Environmental  Justice,   and   Nitrogen/Co-
pollutants).

Topic 1:  Integrated Risk Information
System (IRIS)
The IRIS program will continueto produce robust
and responsive assessments to characterize
risks addressing Agency priorities. The program
is implementing enhancements to the efficiency
of its process and stakeholder  engagement,
providing more opportunity for participation in
problem formulation and tailoring the scope of
its assessments. A multi-year plan resulting from
significant program partner  input will  ensure
that the highest priorities for the Agency will be
addressed and timely, and a process to  update
IRIS assessments will ensure  that assessments
remain based  on the most relevant and  current
information for key chemicals.  Incorporating
advances in assessment methods will  include
application of  systematic  review  methods
for hazard  characterization  and   evidence
integration,  and  new  methods for  dose-
response analysis and insights from mechanistic
understanding will be applied when mature.
Public science meetings and ongoing website
upgrades  will   enhance  communication  of
the program's  progress and  status,  while  a
handbook of operating procedures will provide
both education,  transparency, and consistency
regarding assessment development. The HHRA
program is  committed to  maintaining IRIS as
the premier source of health hazard and dose-
response information for priority environmental
pollutants.

Topic 2:   Integrated Science
Assessments (ISAs)
The HHRA program will continueto work in close
collaboration with the primary client office, the
Office of Air and Radiation's (OAR) Office of Air
Quality Planning and Standards (OAQPS), as well
as the Clean Air Scientific Advisory Committee
(CASAC) and other stakeholders, to  develop
ISAs as a  major component of its research
portfolio to identify, interpret, and characterize
data on the  health and  environmental effects
of exposure to criteria air pollutants. The HHRA
program also provides sustained scientific and
technical support during  the development
of exposure, risk, and  policy assessments by
OAQPS, and during national rule development.
Advances in scientific  understanding  of the
MOA and key events of the disease pathways
for these  pollutants will  help integrate  the
evidence for determining these risks as well as
inform approaches for other HHRA assessment
products such as the IRIS assessments. During
the FY2016-2019  period,  other innovations
in analysis approaches  are anticipated as the
HHRA  program  grapples  with  characterizing
the health and welfare effects of SO2 and NO2.
New insights on determinants of PM toxicity
will inform  ISA  development and use as the
scientific basis for decisions to  retain or revise
the National Ambient Air Quality Standards.

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Topic 3:  Community and Site-
specific Risk
The  HHRA  program will continue to support
the risk management decisions required by the
Office of Solid Waste and Emergency Response
(OSWER), and to address  community needs.
Annual  production of  PPRTV  assessments
targeted  to  the  priorities  of  OSWER  will
continue  to provide the scientific support for
decisions on  the management of municipal
and hazardous waste sites. Application of new
data streams  and approaches will  occur as
their utility is characterized  and may extend
to additional  assessment  products  for rapid
response to urgent contamination situations.
Significant technical support will continue to aid
regions in implementation  and understanding
of these assessments. Efforts on extending
and  targeting  cumulative  risk   assessment
methods  to integrate multiple  stressors  will
help communities understand and characterize
their  "place-based" concerns.  Specific  case
studies and approaches will be explored to
develop exposure and risk apportionment to
different exposure media (air, water,  land)  and
to provide for the integration of ecological  and
human effect measures. We also anticipate that
work on the role of susceptibility and epigenetic
markers will be developed into a framework for
incorporating  these considerations  into CRA
approaches, thereby ensuring relevancy  and
that the latest innovations in biomonitoring are
addressed.
biology  for understanding disease processes
and   ecosystem  impacts.   Refinements  to
current  approaches are  expected  to improve
the accuracy, efficiency,  flexibility, and  utility
of applications  across the large landscape of
assessment  activities  served  by  the  HHRA
program and  position it  to be  both  more
agile  and  better  support   characterization
of  wellness  and  sustainability.   Sustaining
support of databases and software will ensure
transparency  of  assessments and  facilitate
communication and consistency of assessment
development.  Training  will   increase   both
understanding of  methods  and  stakeholder
capability for applying assessment advances.
Some specific  areas  to  be  advanced are:
refinements to  systematic review, extensions
of dose-response analyses for model averaging
and data integration, and approaches to benefit-
cost analyses and  uncertainty characterization.
Updates to  dosimetry models will facilitate the
use of MOA and AOP insights and  inform new
approaches to the characterization of  acute,
short-term, and episodic exposures. Application
of emerging  sensor data will include  both
analytical  considerations and  interpretation,
while updates to exposure assessment tools
will continue to  be developed  to  translate
and describe factors that  influence exposure
characterization.
Topic 4:  Advancing Analyses and
Applications
Projects  in this  area cut across the  entire
HHRA  program portfolio to ensure that  its
assessment products will keep contemporary
with emerging concepts in  hazard  and dose-
response  assessment,  exposure   sciences,
advances in biotechnology, and the evolution
of  computational  approaches  and systems

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Conclusions
Human health risk assessment is the process
of  analyzing   information  to  estimate  the
potential   for  an  environmental  pollutant
to harm  exposed persons  and ecosystems,
and the assessment documents that are the
product of this process are fundamental to
environmental management decision making.
Scientific  evidence from diverse  disciplines
must be systematically identified, consistently
evaluated  for scientific merit and  relevance,
and  integrated   to   support  development
of  human  health and environmental  risk
assessments.  By fully  engaging the scientific
and policy communities in the HHRA program,
EPA  is producing reliable,  transparent,  and
high-quality assessments while identifying the
scientific  research needed to advance future
assessments and ensure effective  translation
and communication of the Agency's assessment
methods, models, and data. The outcome of
this HHRA Strategic Research Action Plan will
be  highly  influential  scientific  assessments
used to support important and complex Agency
decisions to protect human health and the
environment,  coupled  with  advances  in risk
assessment methods that increase  confidence
in the application  of science to support such
decisions.

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References
Gallagher, S. S., Rice, G. E., Scarano, L J., Teuschler, L K., Bollweg, G., Martin, L (2015). Cumulative
risk assessment lessons learned: a review of case studies and issue papers. Chemosphere. Feb;120,
697-705.

Jarabek, A. M., Pottenger, L. Hv Andrews, L. S., Casciano, D., Embry, M. R., Kim, J. H., Preston, R.
J., Reddy, M. V., Schoeny, R., Shuker, D., Skare, J., Swenberg, J., Williams, G. M., Zeiger, E. (2009).
Creating context for the use of DNA adduct data in cancer risk assessment: I. Data organization.
Crit. Rev. Toxicol. 39(8), 659-78.

Lassiter, M. G., Owens, E. O., Patel, M.  M., Kirrane, E., Madden, M., Richmond-Bryant, J., Mines, E.
P., Davis, J. A., Vinikoor-lmler,  L, Dubois, J. J. (2015). Cross-species coherence in effects and mode
of action in support of causality determinations in the U.S. Environmental Protection Agency's
Integrated Science Assessment for lead. Toxicology. April;330, 19 - 40.

National Research Council.  (2007). Toxicity Testing in the 21st Century: A Vision and a Strategy.
Committee on Toxicity Testing and Assessment of Environmental Agents, National Research
Council, http://www.nap.edu/openbook.php7record id=11970

National Research Council.  (2009). Science and Decisions: Advancing Risk Assessment. Committee
on Improving Risk Analysis Approaches Used by the U.S. EPA; Board on Environmental Studies and
Toxicology; Division on Earth and Life Studies. National Academies of Science, http://www.nap.
edu/openbook.php?record id=12209

National Research Council.  (2011). Review of the Environmental Protection Agency's Draft IRIS
Assessment of Formaldehyde. Committee to review EPA's Draft IRIS Assessment of Formaldehyde;
Board on Environmental Studies and Toxicology; Division on Earth and Life Studies. National
Academies of Science, http://www.nap.edu/openbook.php7record  id=13142

National Research Council.  (2012). Exposure Science in the 21st Century: A Vision and a Strategy.
Committee on Human and Environmental Exposure Science in the 21st Century; Board on
Environmental Studies and  Toxicology; Division on Earth and Life Studies.  National Academies of
Science, http://www.nap.edu/openbook.php7record id=13507

National Research Council.  (2013). Critical Aspects of EPA's IRIS Assessment of Inorganic Arsenic:
Interim Report (2013). Committee on Inorganic Arsenic. Board on Environmental Science and
Toxicology. National Academies of Science, http://www.nap.edu/catalog.php7record id=18594

National Research Council.  (2014). Review of EPA's Integrated Risk Information System (IRIS)
Process. Committee to Review the IRIS Process; Board on Environmental Studies and Toxicology.
National Academies of Science, http://www.nap.edu/catalog.php7record  id=18764 Schulte, P. A.
(1989). A conceptual framework for the validation and use of biomarkers. Environ. Res. 48, 129-
144.

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Thomas, R. S., Wesselkamper, S. C, Wang, N. C. Y, Zhao, Q. J., Petersen, D. D., Lambert, J. C, Cote,
I., Yang, L, Healy, E., Blank, M. B., Clewell III, H. J., Allen, B. C, Andersen, ME. (2013). Temporal
concordance between apical and transcriptional points of departure for chemical risk assessment.
Toxicol. Sci. 134(1), 180-194.

U.S. Environmental Protection Agency. (2003). Framework for Cumulative Risk Assessment.
EPA.600.P-02/001F. http://www.epa.gov/raf/publications/pdfs/frmwrk cum risk assmnt.pdf

U.S. Environmental Protection Agency. (2011). Exposure Factors Handbook: 2011 Edition.
EPA/600/R-09/052F. http://www.epa.gov/ncea/efh

U.S. Environmental Protection Agency. (2014). Next Generation Risk Assessment: Incorporation
of Recent Advances in Molecular, Computational, and Systems Biology. Final report. September.
EPA/600/R-14/004.

U.S. Environmental Protection Agency. (2015) Science Advisory Board. Strategic Research Planning
for 2016-2019: A Joint Report of the Science Advisory Board and Board of Scientific Counselors.
http://vosemite.epa.gov/sab/sabproduct.nsf/c91996cd39a82f648525742400690127/98BF816150
lB5A3C85257DDA005EB913/SFile/EPA-SAB-15-004+BOSC+report-l+26+15-final+unsigned.pdf

Villeneuve, D. L, Crump, D., Garcia-Reyero, N., Hecker, M., Hutchinson, T. H., LaLone, C. A.,
Landesmann, B., Lettieri, T, Munn, S., Nepelska, M., Ottinger, M. A., Vergauwen, L, Whelan, M.
(2014a). Adverse Outcome Pathway (AOP) Development I: Strategies and Principles.  Toxicol. Sci.
142(2), 312-20.

Villeneuve, D. L, Crump, D., Garcia-Reyero, N., Hecker, M., Hutchinson, T. H., LaLone, C. A.,
Landesmann, B., Lettieri, T, Munn, S., Nepelska, M., Ottinger, M. A., Vergauwen, L., Whelan, M.
(2014b). Adverse Outcome Pathway Development II: Best Practices. Toxicol. Sci. 142(2), 321-30.

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Appendix A
Proposed Outputs, Human Health Risk Assessment Research Program FY16-19

The following table lists the expected outputs from the Human Health Risk Assessment research
program,  organized by topic. Note that outputs may change as new scientific findings emerge.
Outputs are also contingent on budget appropriations.
Topic 1
Project 1
IRIS document components
IRIS scientific and technical
consultations
Stakeholder engagement and
outreach for IRIS program
IRIS Handbook of Operational
Procedures
Project 2
Decision Strategy
Reviews and updates
Integrated Risk Information System (IRIS)
IRIS Assessments
Annually released to the public for priority chemicals following
the multi-year agenda posted on the IRIS website:
• Scoping and problem formulation packages
• Literature searches and study tables
• Interagency review drafts
• External peer review drafts
• Final assessments
HHRA scientists provide scientific support to assessments by
identifying issues and advancing solutions;
Technical support to program offices regarding
implementation of IRIS assessments in regulatory applications
(e.g., OAQPS residual technology review, OW contaminant
candidate list, OSWER records of decision)
Bi-monthly scientific meetings on assessment activities;
Regular meetings with program partners regarding priorities
Ongoing guidance on assessment approaches and process
IRIS Updates
FY16 Develop approach for identifying assessments that
should be updated with high priority
FY16 Develop efficient processes for developing and reviewing
updated assessments in a short time
FY16-19 Implement IRIS update decision strategy and regularly
review IRIS values.

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           Topic 2
           Integrated Science Assesssments (ISA)
Project 3
Integrated Science Assessments
ISA science issue workshops
Convene scientific experts to review and identify scientific or
policy issues prior to initiation of ISA development
ISA document drafts
Release external peer review drafts for Clean Air Scientific
Advisory Committee and public reviews
• FY16 1st draft NO2 & SO2 secondary (welfare) ISA
• FY16 2nd draft NO2 & SO2 secondary (welfare) ISA
• FY16 1st draft of ISA for PM
• FY17 2nd draft of ISA for PM

Release final ISA documents in support of National Ambient
Air Quality Standards (NAAQS)
• FY16 Final rulemaking on lead
• FY16 SO2  primary (health)
• FY17 NO2 & SO2 secondary (welfare)
• FY18 Final rulemaking on SO2 primary (health) and
  NO2  primary (health)
• FY19 Final rulemaking on NO & SO secondary (welfare)
ISA-related scientific and
regulatory support
Support to Office of Air and Radiation regarding
implementation of ISA to policy assessment and rule making
for decisions regarding review, retention or revision of the
NAAQS
• FY16 Integrated review plan for PM ISA
• FY16-18 NO2 primary (health) ISA
• FY16-18 SO2 primary (health) ISA
ISA-related scientific
advancements
Multipollutant science document health issues;
Multipollutant science document on the effects of the criteria
pollutants on climate forcing;
Publications and scientific analyses to support the ISAs

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Topic 3
Project 4
PPRTV assessments
Project 5
Superfund Technical Support
Center and Ecological Risk
Assessment Support Center
Report on technical support
Emergent issues and other
Agency priorities
Project 6
Approaches to cross-species
data integration to support
cumulative risk assessment
(CRA)
Incorporating multiple stressors
Incorporating susceptibility
information into CRA
Apportioning multimedia
exposure and risk across human
and ecological receptors
Community and Site-specific Risk
Provision peer-reviewed toxicity values (PPRTV) assessments
>12 developed annually in support of OSWER site
management decisions
Site-specific and Superfund Regulatory Support
FY16-19 Provide on-going support to EPA regional offices for
Superfund risk assessment activities and scientific support for
ecological risk assessment
FY16-19 Provide quarterly reports on technical support
FY16-19 Annually provide rapid assessment response (e.g.,
West Virginia MCHM spill) or other scientific support on
Agency priorities as requested by programs, regions, EPA
Science Advisory or Administrator
Cumulative Risk Assessment Methods and Applications
FY17 Publication of case study(s) to advance incorporation of
ecological risk assessment into CRA framework
FY18 Develop multi-criteria decision analysis approaches
to integrate ecological and human health indices and aid
transparency of valuations
FY16 Publication of journal manuscript describing use of
directed acyclic graphs for drawing causal inference in CRA
FY17-19 Case studies and methods development to
characterize risks posed by multiple chemical and non-
chemical stressors to human health.
FY16 Report from science workshop on epigenetics and CRA
FY19 Publication of a framework for interpreting epigenetic
information in risk assessment
FY17 Modeling of dermal and inhalation exposures to diethyl-
and di(l-n-butyl) phthalate to inform evaluation of mixtures
FY18 Apportioning multimedia exposure and risk across
human and ecological receptors
FY16-19 Support Risk Assessment Forum activities on
cumulative phthalate exposures

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Topic 4
Project 7
Advancing methods for
systematic review and evidence
integration
Advancing quantitative
methods
Advancing methods for benefits
and uncertainty analyses
Characterizing determinants of
risk: Concentration, duration
and timing of exposure
Scientific workshops on major
risk assessment methodology
issues
Project 8
Disease-based integration of
new data types
Characterization and
quantitative application of high-
throughput screening (HTS) and
other data-mining derivations
Advancing Analyses and Applications
Advancing Hazard Characterization and Dose-Response
Methods
FY16 Scientific workshop report on advancing systematic
review
FY17 New methods to improve evidence identification,
evaluation and evidence integration
FY17 Refine study quality evaluation approaches
FY18 Develop multivariate dose-response analysis methods
FY19 Report on best practices for non-parametric, semi-
parametric, and parametric dose-response modeling methods
FY19 Report on methods to advance meta-analyses and
Bayesian approaches
FY18-19 Case studies to evaluate approaches to probabilistic
derivation of reference values to support benefits analysis
FY17 Publish workshop report on Temporal Issues for
Environmental Pollutants: Health Effects and Methodologies
for Estimating Risk
FY19 Report on evaluation and quantification of early-life
exposures for non-cancer and cancer outcomes
FY19 Concentration-duration-response surface evaluation and
interpretation to support derivation of assessments of acute,
short-term, episodic and lifetime exposures
FY16-19 Convene scientific workshops held with subject
matter experts to address current challenges and advance
approaches to risk assessment
Applying Emerging Science to Inform Risk Screening and
Assessment
FY19 Case study(s) of disease-specific assessment of multiple
environmental risk factors to illustrate integrated use of
multiple, new advanced biological data types
FY18 Case studies to characterize the utility of HTS and other
data for various classes of chemicals and various endpoints
commonly encountered in risk assessment
FY18 Adverse outcome pathway (AOP) footprinting: hazard
grouping and quantitative analysis for mixtures assessment of
toxicologically uncharacterized stressors

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Dosimetry21: Advancing
multiscale dosimetry models
to incorporate AOP/Mode of
Action (MOA) and biomarker
data
FY16-17 Convene Federal community of practice to develop
an issue paper for NRC review and report regarding need for
multiscale measurement and models to address application of
AOP/MOA or biomarker data and realize vision of Tox21 and
Exposure21 reports
FY19 Development of a suite of model structures including
portal-of-entry for each route and implementation via
development of methods and case studies to implement
anticipated NRC recommendations
Evaluation and application
of new exposure data and
methods
FY17 Advancements and updating of Exposure Factors
Handbook (Draft food intake)
FY17 Release of ExpoFIRST - quick, easy, and flexible
development of human exposure scenarios (I? and final)
FY18 Release of EPA-Eco-Box - quick, easy, and flexible
development of ecologic risk assessment scenarios (draft and
final)
FY16-18 Collaboration with NIOSH Center for Direct
Reading and Sensor Technologies and the cross-agency
Air Sensors Health Group to develop criteria for analytical
characterization, integration of sensor data  with dosimetry
modeling, interpretation of sensor data on application to risk
assessment, and recommendations regarding best practices
for management and curation of sensor data.
Project 9
Risk Assessment Support and Training
Development and maintenance
of essential software and
support tools
FY16-19 Update and maintain software supporting critical
infrastructure activities including data access (IRIS website)
and assessments (Health and Environmental Research Online);
benchmark dose software, PBPK/dosimetry software, etc.
FY16-19 Development of new software modules to implement
advances in evidence integration and dose-response methods
and applications of new data streams and mechanistic data
mining
Development and application
of risk assessment training
FY16-19 Provide ongoing outreach to states, regions, program
offices and international entities interested in training on risk
assessment approaches and techniques

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Appendix B.   Executive  Orders and  EPA  Policies

HHRA Supports

Executive Order 13045: Protection of Children from Environmental Health Risks and Safety
Risks, which states that each federal agency "(a) shall make it a high priority to identify and assess
environmental health risks and safety risks that may disproportionately affect children; and (b)
shall ensure that its policies, programs, activities, and standards address disproportionate risks to
children that result from environmental health risks or safety risks."

EPA's 1995 Policy on Evaluating Risk to Children, which states that "It is the policy of the U.S.
Environmental Protection  Agency (EPA) to consider the risks to infants and children consistently
and explicitly as a part of risk assessments generated during its decision making process, including
the setting of standards to protect public health  and the environment."

Executive Order 12898: Federal Actions To Address Environmental Justice in Minority
Populations and Low-Income Populations, which states that "(a) Environmental human health
research, whenever practicable and appropriate, shall include diverse segments of the population
in epidemiological and clinical studies, including segments at high risk from environmental
hazards, such as minority  populations, low-income populations and workers who may be exposed
to, substantial environmental hazards" and "(b) Environmental human health analyses, whenever
practicable and appropriate, shall identify multiple and cumulative exposures."

EPA's 2011 Environmental Justice Action Plan ("Plan EJ 2014"), which established measurable
commitments that address the Agency's national environmental justice priorities. These priorities
created an Agency-wide focus on matters that environmental justice advocates and others have
identified as critical environmental justice issues. In 2015, EPA is developing the EJ 2020 Action
Agenda, the Agency's next overarching strategic plan for environmental justice.

Executive Orders 12866,13563 and OMB Circular A-4, which guide the analysis of the costs
and benefits of Federal regulatory decisions, including the assessment of the public health and
environmental benefits associated with regulatory options. HHRA health assessments play a
crucial role in the assessment of the  benefits of actions taken by EPA; potential improvements in
how noncancer dose-response is quantified, as discussed  elsewhere in this document, have been
identified as important to  advancing EPA benefits analysis for regulatory support.

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Appendix C.   Research  Program  Partners  and
Stakeholders
Note: HHRA works with many partner and
stakeholder organizations, and new partnerships
are continually forming; therefore, this list is not
comprehensive.

EPA Board of Scientific Counselors (BOSC)
EPA Clean Air Scientific Advisory Committee
(CASAC)
EPA Science Advisory Board (SAB)
    Chemical Assessment Advisory Committee
    (CAAC)
EPA Regions 1 - 10
Office of Air and  Radiation (OAR)
    Office of Air Quality Planning and
    Standards (OAQPS)
    Office of Transportation and Air Quality
    (OTAQ)
Office of Chemical Safety and Pollution Prevention
(OCSPP)
    Office of Pesticide Programs (OPP)
    Office Pollution Prevention and Toxics
    (OPPT)
    Office of Science Coordination and Policy
    (OSCP)
Office of Children's Health Protection (OCHP)
Office of Environmental Justice (OEJ)
Office of Policy (OP)
    National Center for Environmental
    Economics (NCEE)
Office of the Science Advisor (OSA)
Office of Solid  Waste and Emergency Response
(OSWER)
    Office of Emergency Management (OEM)
    Office of Underground Storage Tanks
    (OUST)
    Office of Superfund Remediation and
    Technology Innovation (OSRTI)
    Office of Resource Conservation and
    Recovery (ORCR)
    Office of Program Management (0PM)
Office of Water (OW)
    Office of Ground Water and Drinking Water
    (OGWDW)
    Office of Science and Technology (OST)
Other Governmental Stakeholders
Agency for Toxic Substances and Disease Registry
(ATSDR)
California's Environmental Protection Agency
(Ca I/EPA)
  Office of Environmental Health Hazard
  Assessment (OEHHA)
Centers for Disease Control and Prevention (CDCP)
Department of Defense (DoD)
  Air Force Research Laboratory (AFRL)
  Army Corps of Engineers (ACE)
  Army Public Health Command
  Defense Advanced Research Projects Agency
  (DARPA)
  Naval Medical Research Unit (NAMRU)
Department of Labor
  Occupational Safety and Health
  Administration (OSHA)
Food and Drug Administration (FDA)
  National Center for Toxicological Research
  (NCTR)
National Academy of Sciences (NAS)
Government Accountability Office (GAO)
National Institutes of Health (NIH)
  National Cancer Institute (NCI)
  National Institute of Environmental Health
  Sciences (NIEHS)
        Chemical Genomics Center (CGC)
        National Toxicology Program (NTP)
Texas Commission on Environmental Quality
(TCEQ)
Nongovernmental Organizations
Alliance for Risk Assessment (ARA)
American Public Health Association (APHA)
American Chemistry Council (ACC)
  Long-Range Research Initiative (LRRI)
Environmental Working Group (EWG)
Environmental Defense Fund (EOF)
Environmental Council of the States (ECOS)
Interstate Technology and Regulatory Council
(ITRC)
Integrated Life Sciences Institute (ILSI)
  Health and Environmental Science Institute
  (HESI)
National Resource Defense Council (NRDC)

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Appendix D.

Enhancements to  IRIS

Program

The  IRIS program  develops human  health
assessments  that  provide  health   effects
information on  environmental  chemicals to
which the public may  be exposed, providing
a critical  part of the scientific foundation for
EPA's decisions to protect public health. In their
report Review of the Environmental Protection
Agency's Draft IRIS Assessmentof Formaldehyde,
the National  Research Council  (NRC) made
several recommendations to EPA for improving
IRIS assessments and the IRIS program (NRC,
2011).  The  NRC's  recommendations  were
focused on the first step of the IRIS process, the
development of draft assessments. Consistent
with the  advice of the  NRC, the IRIS program
is implementing these recommendations using
a phased approach and  is making the most
extensive changes to assessments that are in
the earlier stages of the IRIS process.

EPA agreed with the NRC's  2011  recom-
mendations for the development of IRIS assess-
ments and is fully implementing them  consis-
tent with the report's "Roadmap for Revision,"
which viewed the full implementation of their
recommendations  by the IRIS  program as a
multi-year process.  In response  to the NRC's
2011 recommendations, the  IRIS program has
made  changes to streamline the assessment
development  process,  improve  transparency,
and create efficiencies in the program. The NRC
has acknowledged EPA's successes in this area.
Their May 2014 report Review of the Integrated
Risk Information System  (IRIS) Process, finds
that EPA  has made substantial  improvements
to the IRIS program in a short amount of time
(NRC, 2014). They also  provide several recom-
mendations which they say should be seen as
building on the progress that EPA has already
made.

This appendix provides a brief summary of the
status of enhancements to the IRIS program.
Strengthening and streamlining the IRIS  pro-
gram is an ongoing priority for the HHRA pro-
gram. As the IRIS program continues to evolve,
the HHRA program is committed to evaluating
how well its approaches promote constructive
public discussion with its stakeholders, as well
as reviewing how these  approaches can more
effectively facilitate subsequent assessment de-
velopment. Enhanced stakeholder engagement
will help to ensure transparency and the use of
the best available science in IRIS assessments.
More information on the IRIS program's recent
enhancements can  be  found at http://www.
epa.gov/IRIS/process.htm and http://www.epa.
gov/IRIS/pdfs/irisprocessfactsheet2013.pdf.

Enhancements to  the  Development
Process

The IRIS program is implementing thefollowing,
which will help meet the goal  of producing
high-quality assessments that are tailored to
program  needs in a  timely  and transparent
manner:

• Internal  planning and scoping meeting to
  identify  EPA needs, followed by a public
  meeting to identify the available scientific
  information  for  the   chemical   under
  assessment.

• Publicly  release the literature  search  and
  search strategy, evidence tables, exposure-
  response  figures  and information  on key
  scientific issues for the chemical. Convene a
  public meeting to discuss these materials.

• Publicly  release a  draft assessment  and
  peer review charge for comment at  a public

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meeting (these may  be revised as needed
after the public meeting).

Improving the Science of IRIS
Assessments

Thefollowing changes were either implemented
or are in progress to improve the quality and
clarity of IRIS assessments:

• Implemented a new document structure that
  is clear, concise and systematic.

• Incorporated a preamble that describes the
  application of existing EPA guidance and the
  methods and criteria used in developing the
  assessments.

• Strengthened its practices for peer  review
  and protection against conflict of interest.

• Dedicated  a specific  Chemical  Assessment
  Advisory  Committee  (CAAC) of  the
  Scientific  Advisory  Board (SAB) to  review
  IRIS  assessments.   More information
  on the SAB  CAAC  can  be  found  at:
  http://yosemite.epa.gov/sab/sabpeople.
  nsf/WebCommitteesSubcommittees/
  Chemical%20Assessment%20Advisorv%20
  Committee.

• Created Discipline-Specific Workgroups and
  Interdisciplinary Science Teams to evaluate
  endpoint-specific  and  disciplinary  issues
  relevant to an  assessment.  These  groups
  coordinate  across  assessments  to  ensure
  consistency,   solve   cross-cutting   issues,
  and   advance  scientific   understandings
  that contribute  to  decision making  in IRIS
  assessments.

• Adopted  systematic  review  methods  and
  information management tools to improve
  study   selection  and  analyses   including
  improvements to the following:
   ° Evidence Identification: Literature
    Collection and Collation Phase
    A separate section provides a detailed
    description of the literature search
    and associated search and screening
    strategy  to  identify  and   select
    pertinent studies.
  ° Evidence   Evaluation  for   Hazard
    Identification -  The  IRIS program
    is in the process of improving and
    standardizing   the   approach   to
    evaluating evidence and standardizing
    the documentation of this evaluation.
  ° Developed standardized presentation
    of  evidence  tables  and  exposure-
    response   arrays   to   succinctly
    summarize study design and findings.
  ° Improved   process  for   selecting
    studies for dose-response evaluation.
  ° Currently  evaluating considerations
    for combining data for dose-response
    modeling and analysis.

Enhancements to Improve
Productivity and Transparency in
the IRIS Program

• Improved workforce planning to help increase
  assessment output  and improve  scientific
  evaluation.

• Conducting  a survey  of EPA program and
  regional offices to identify and evaluate client
  demands and the resources required to meet
  user needs.

• Focused staff attention on a smaller number
  of assessments  to ultimately increase the
  efficiency and output of the program.

• Established a set of "stopping rules" for new
  data  and scientific  issues  to help ensure
  that  IRIS assessments are not delayed by
  new research findings  or ongoing debate of
  scientific issues after certain process points
  have passed.  Additional information about
  the stopping rules is available at http://www.
  epa.gov/iris/pdfs/IRIS stoppingrules.pdf.

• Improved stakeholder engagement in the IRIS
  process throughout assessment development

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through the conduct of IRIS Public Science
meetings.  These  meetings  benefit  from
the  participation  of  independent  experts
identified by the NRC who provide input on
the scientific and  technical aspects of IRIS
chemical assessments.

Holding peer consultation science workshops
which may focus on the state of the science
for a particular chemical or provide a forum
for discussion  with  experts  about certain
cross-cutting scientific issues that may impact
the development of  a scientifically complex
assessment.

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