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

SRA 2013 Annual Meeting Abstracts
M2-F.4 Reinhardt, JC*; Chen, X; Liu, W; Manchev, P;
Paté-Cornell, ME; Stanford University; reinhardt@stanford.edu
Project Fox: Taming Asteroid Risks
Understanding and mitigating the risks posed by asteroids is
important to the scientific and policy-making communities, as
near earth objects threaten human lives and may threaten the
very existence of human civilization. Qualitative and
quantitative studies have been done to assess such risks, and
some reasonable point estimates have been proposed. However,
due to the low probability/high consequence nature of asteroid
risks, these measures provide limited actionable insights and
may even lead to false confidence when interpreted
inappropriately. Project Fox aims to provide a probabilistic
model that evaluates the collective threat from asteroids
events. We implement a modularized simulation architecture
that takes probabilistic inputs to construct the probability
distribution of rare events efficiently. The model suggests that
although the point estimates of annual death rates due to
asteroid events have small numerical values, the probability of
incurring a catastrophic loss of human lives and property
damages is significant. Furthermore, the probability of a
cataclysm scenario (an impact event with globally reaching
consequences) due to asteroid impacts is far from negligible,
and the current understanding of impactors that could trigger
global consequences underestimates the actual risk by leaving
a large fraction of cataclysmic risk scenarios unaccounted for.
Specifically, we find that the majority of global consequence
risk is attributable to asteroids between 300 and 1000 meters
in diameter, signaling the importance of missions to observe
and track asteroids in this range. Finally, “civil-defense”
counter-measures mitigate the risk of human casualties from
asteroid impacts to some small level, but they are certainly not
a panacea. Because of the potentially poor performance of civil
defense methods, further analysis on the effectiveness and
feasibility of space missions to interdict asteroids are
warranted.
W2-F.3 Reiss, R; Exponent; rreiss@exponent.com
What can we learn and apply from journal peer review?
Scientific peer review is a critical component of the regulatory
process. The peer review model has been used in the evaluation
of scientific papers for publications long before peer review was
used for regulatory programs. Therefore, it is reasonable to ask
if there are lessons from the journal peer review process that
can be applied to regulatory peer review. Some of the issues
that will be discussed include the selection of peer reviewers,
achievement of balance of perspectives in peer review, and the
requirements to respond and modify analyses based on peer
review. Another area for improvement is the process of revision
that occurs after a peer review. The journal model of accepting,
rejecting, or sending papers back for more work, may provide a
possible model for regulatory peer reviews. Another topic that
will be discussed is a possible model for enhanced review of
select regulations that are of high value, such as sending a
select number of assessments automatically to the National
Academy of Sciences each year. All of these ideas have to be
balanced with the need for timely assessments.
W4-G.1 Reitman, F*; Sun, T-J; Beatty, P; LeHuray, AP;
Hammon, TL; Juba, MH; Palermo, C; Lewis, RJ; White, RD; 1
Shell; 2 Chevron; 3 American Petroleum Institute; 4
Naphthalene Council; 5 ConocoPhillips; 6 Koppers, Inc.; 7, 8
ExxonMobil Biomedical Sciences, Inc. 9 American Petroleum
Institute; alehuray@comcast.net
Naphthalene Rodent Inhalation Bioassays and
Assessment of Risk to Exposed Humans: Problem
Formulation
The National Toxicology Program (NTP) conducted 2-year naphthalene
inhalation cancer bioassays in B6C3F1 mice (1992) and in F-344 rats (2000)
and observed cancers in the mouse lung and the rat nose. Naphthalene
exposure was not previously thought to pose a cancer risk, however, based
on these two NTP studies EPA’s Integrated Risk Information System (IRIS)
released a draft cancer risk assessment in 2004 which proposed
naphthalene as “likely to be carcinogenic in humans”, with a calculated
cancer potency 10 to 40-fold greater than benzene. However, the available
human and mechanistic toxicity data did not support the association
between naphthalene exposure and cancer, particularly nasal cancer. A
2006 Naphthalene State- of- Science Symposium (NS3), independently
organized and funded by EPA, Naphthalene Research Committee (NRC)
members and others, provided a rigorous review of the state -of-science for
cancer risk assessment. The NS3 raised concerns in extrapolating these
rodent bioassay results to human cancer risks including: (1) the NTP
bioassays were conducted at high vapor concentrations above the Maximum
Tolerated Dose, complicating low-dose extrapolation, (2) naphthalene likely
does not represent a classical genotoxic carcinogen, (3) cytotoxicity and
cellular proliferation appears to have played a role in the carcinogenic
responses, (4) tumor formation rates at environmental, noncytotoxic
exposure levels cannot be meaningfully predicted by simple linear
extrapolation from the tumor rates observed in the rodent bioassays, and (5)
there are important differences in naphthalene metabolism and toxicity
between rodents and humans. Based on the study recommendations from
NS3, industry associations and individual companies formed the NRC to
co-sponsor research that strives to improve naphthalene risk assessments.
The NRC’s objective has been to collect data to properly evaluate the
carcinogenic potential of naphthalene.
T1-F.1 Renn, O; University of Stuttgart;
ortwin.renn@sowi.uni-stuttgart.de
Emerging Risks: Concepts and Approaches
Emerging risks denote future threats where the potential losses
as well as the probability distribution of their occurrence are
either unknown or contested. Emerging risks may be further
broken down into three distinct, but overlapping categories,
based on their main characteristic at a certain stage. These
categories are described as follows: (i) Emerging technologies
with emerging risk profile based on high uncertainty and lack
of knowledge about potential impacts and interactions with the
affected risk absorbing systems; (ii) Emerging technological
systems with emerging interactions and systemic dependencies.
The main issue here is the not the risk of the technologies (that
may be known or well estimated) but the interactions of these
risk (and also benefits) with other types of risks or activities
that could lead to non-linear impacts and surprises; and (iii):
Established technologies in a new emerging context or
environment: The main problem here is that familiar
technologies are operated in a new context or in different
organizational settings that may change both the probability as
well as the magnitude of potential impacts. One could also
include here risks driven by complacency and overconfidence
on one’s own ability to cope with sudden crisis. Conventional
approaches to projecting loss size, relative frequencies or
probability distributions over time or severity of consequences
are usually ineffective if applied to emerging risks.
Furthermore, attempts to assess emerging risks with technical
or scientific instruments may prove futile as scientific
understanding of emerging risks can change rapidly. Therefore,
adaptability and flexibility are vital to manage emerging risks in
terms of individual, social, and economic impacts. This paper
aims at developing a conceptual orientation for risk managers
to better address emerging risks and be better prepared for the
challenges of the future.
December 8-11, 2013 - Baltimore, MD