Abstracts (PDF file, 1.8MB) - Society for Risk Analysis

SRA 2013 Annual Meeting Abstracts
T1-B.1 Olden, K*; Vandenberg, J; Kadry, A; Deener, K; US
Government; kadry.abdel@epa.gov
Advancing Human Health Risk Assessment at the United
States Environmental Protection Agency
There are currently more than 80,000 chemicals in commerce,
and an additional 1,000 new chemicals are introduced each
year. Only a small fraction of these chemicals have been
adequately assessed for potential risk. Human health risk
assessment (HHRA) is a critical tool for characterizing the
potential risk to human health of exposure to environmental
contaminants. To produce defensible, scientific assessments of
risk and therefore make defensible decisions to manage or
mitigate risk, risk assessors and managers need scientifically
rigorous information about hazard, dose-response and
exposure. EPA’s HHRA research program develops health
assessments that include hazard identification and
dose-response information; exposure and risk assessment tools;
and methods to advance the science of human health risk
assessment. This information is used by EPA and others to
make decisions, develop regulatory standards for
environmental contaminants, and manage cleanups. The HHRA
program is committed to generating timely, credible human
health assessments of individual chemicals and chemical
mixtures to support priority EPA risk management decisions,
thereby enabling EPA to better predict and prevent risk. The
program is compromised of four research themes: 1) Integrated
Risk Information System (IRIS) health hazard and
dose-response assessments; (2) Integrated Science
Assessments (ISAs) of criteria air pollutants; (3) Community
Risk and Technical Support for exposure and health
assessments; and (4) Methods, models, and approaches to
modernize risk assessment for the 21st century. The HHRA
research program collaborates with Agency, federal, state,
regional, national, and international partners in the scientific
and risk assessment communities to ensure that assessment
products are scientifically rigorous, developed in a transparent
manner, and relevant to stakeholder needs. The views
expressed in this abstract do not necessarily represent the
views or policies of the U.S. Environmental Protection Agency.
P.146 Ollison, W*; Capel, J; Johnson, T; 1 - American Petroleum
Institute, 1220 L Street, NW, Washington, DC 20005; 2 -
Consultant, 1005 Demerius Street, Durham, NC 27701; 3 - TRJ
Environmental, Inc., 713 Shadylawn Road, Chapel Hill, NC
27914; ollisonw@api.org
Sensitivity of regulatory ozone risk assessment to
improved exposure and response models
We evaluate the sensitivity of EPA’s current ozone (O3)
exposure model (APEX) to (1) alternative pulmonary function
response models, (2) attainment AQ rollback approaches, (3)
altitude effects, and (4) newly measured O3
penetration/deposition rates and microenvironmental (ME)
factors, corrected for O3 measurement error. Results are
provided for Denver air quality (AQ) scenarios representing
2006 “as is” conditions and the attainment of the current ozone
NAAQS. We test recently published pulmonary function models
that incorporate realistic O3 response thresholds and subject
response variability proportional to the level of response. A
CAMx model is used to adjust 2006 Denver AQ to simulate
NAAQS attainment conditions. The modeled rollback
projections account for NOx control-related increases in urban
and background O3 levels from reduced NO-O3 titration that
are not addressed by EPA’s quadratic rollback approach.
Inhaled O3 mass is adjusted to account for altitude acclimation
among Denver residents. Impacts of newly measured indoor O3
penetration-deposition rates on estimated responses are
compared to projections using current APEX indoor
mass-balance model assumptions. APEX ME factors are also
adjusted according to recent field measurements made using
new interference-free O3 photometers. Cumulative impacts of
these updated components in the APEX exposure analysis are
tabulated and compared to those of the current APEX model.
W2-H.4 Olson, KC*; Karvetski, CW; George Mason University;
kolson8@gmu.edu
Probabilistic Coherence Weighting for Increasing
Accuracy of Expert Judgment
In this presentation, we provide a new way to generate
accurate probability estimates from a group of diverse judges.
The experiments we report involve elicitation of probability
estimates that belong to sets in which only one probability is of
primary interest; the other estimates serve to measure the
individual judges' coherence within sets. These experiments
extend previous efforts to increase accuracy of aggregate
estimates by weighting probabilistic forecasts according to
their coherence. Our method shows that asking for only two
additional judgments can achieve significant increases in
accuracy over a simple average. In the aggregation, we adjust
the judgments of each participant to be coherent and calculate
weights for the judgments based on the earlier incoherence
across all participants. More generally, our findings provide
insight into the trade-off between methods that aim to increase
accuracy of judgments by improving their coherence with
experimental manipulations and methods that leverage the
incoherence of judgments to increase accuracy during
aggregation. Our two studies show that concurrent judgments
of related probabilities produce more accurate equal-weight
averages but have less incoherence on which our coherence
weighting operates. However, independent judgments of
related probabilities produce less accurate linear averages but
have more incoherence on which our coherence weighting can
capitalize.
M3-I.3 Orosz, M*; Salazar, D; chatterjee, S; Wei, D; Zhao, Y;
University of Southern California; mdorosz@isi.edu
Using PortSec for policy-making and risk-benefit
balancing
Seaports, airports, and other transportation nodal points face
many challenges – including maximizing operational efficiency,
minimizing risk from terrorism or other man-made and natural
disaster events and minimizing impacts to the environment.
Often these challenges are at odds with one another –
increasing one often comes at the expense of achieving others.
This is particularly true in our Nation’s seaport infrastructures
where there is a need to secure the ports but not at the expense
of maintaining port operations. The University of Southern
California’s National Center for Risk and Economic Analysis of
Terrorism Events (CREATE) is developing PortSec – Port
Security Risk Analysis and Resource Allocation System. Under
funding from DHS S&T and in collaboration with the Ports of
Los Angeles and Long Beach (POLA/LB) and the USCG, USC is
currently extending a previously developed proof-of-concept
PortSec prototype used for tactical security decision-making
into a tool that allows decision-makers to examine the trade-offs
in implementing security measures to protect the port and
support continued movement of shipped goods.
December 8-11, 2013 - Baltimore, MD