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Embracing C
omplexity and Change:
Systems Approaches to Risk
Analysis for Nanomaterials
Pro
f. J
en
nif
er
Ku
zm
a&
Ro
xa
nn
e L
. J
oh
ns
on
Mid
we
ste
rn S
tate
s R
isk
As
se
ss
me
nt
Sym
po
siu
m
Ind
ian
ap
oli
s,
IN
No
ve
mb
er
4,
20
09
Outline
•Engineeerednanomaterialsand environmental risk
•System dynamics background
•Goals of applying SD to ENM & RA
•Case study: nano-scale zerovalentiron for ground
water remediation
•Concluding thoughts
State of Nanomaterialsin the
Environment
•Nanomaterials
entering society at a rapid
pace (over 1000 consumer products, many
others)
•Manufacturing, use, and disposal occurring
•Lim
ited, but growing, body of toxicology
studies
•Increasing number of models to assess risks
Environmental Risk Pathways
Royal Society 2004
Risk Assessment Models
Problem: little data to fill boxes
Morgan 2005
Dual Nature of Nanomaterials
Promise
Pitfalls
Increased surface area
Increased reactivity?
Increased bioavailability and
targeted to certain tissues
Increased toxicity?
Lower doses effective
Lower doses toxic?
Penetration ability for remediation
Impair subsurface ecosystems?
Skin, membrane penetration may
speed onset of action
Toxicity through nontraditional
routes of administration?
Risk-relevant studies
As compiled by Shatkin
2009
Life cycle risk assessment
State of Nanomaterials
and
Environmental Risk Assessment
•Many unresolved questions about how special properties of
nanotechnology affect risk
•Heterogeneity of particular engineered nanomaterials
(ENMs)
•Exposure at various stages of product life-cycle to various human and
ecological endpoints remains largely unknown
•Layer complexity of ENMsupon complexity of environmental pathways
and endpoints
•Overw
helm
ing and nearly impossible to focus on DETAILS (events)
Events and Decisions
Events and Decisions
Patterns of Behavior
Patterns of Behavior
System
Structure
System
Structure
Reactive
Reactive
Adaptive
Adaptive
Generative
Generative
Increasing leverage
Increasing leverage
The Systems Perspective
Adapted from G
. Richardson, U of Albany
Focuses on patterns of behavior (not just specific events)
Focuses on policy structure (not just discrete decisions)
•Considers
–Stocks or Accumulations (populations, resources…)
–Causal structure: “feedback”loops
–Delays
–Perceptions (a kind of accumulation)
–Pressures
–Affects, emotions, (ir)rationalities
A systems perspective
Feedback Loops—Context for Risk Analysis
Decision
sState
of
the sys
tem
Action
Percept
ions
Adapted from G
. Richardson, U of Albany
�Action—use of a nanomaterial
�State of system—natural
interactions of nanomaterialwith
biophysical surroundings
�Perceptions—understanding of
and attitudes about the system state
�Decisions—risk m
anagement,
product approval and use decisions,
or overarching policy approaches
Two kinds of feedback loops
•R
ein
forc
ing
lo
op
s
–growth producing
–destabilizing
–accelerating
–even number of –’s
–“positive”loops
•S
ym
bo
lize
d b
y
•B
ala
nc
ing
lo
op
s
–counteracting
–goal seeking
–stabilizing
–odd number of –’s
–“negative”loops
•S
ym
bo
lize
d b
y
RC
B
Adapted from G
. Richardson, U of Albany
Reinforcing and Balancing Loops
Popu
lation
Birth
s pe
r
year
+
+
Popu
lation
Outmigration
+
–
8 6 4 2 01
50
01
60
01
70
01
80
01
90
02
00
0
10,000
7,500
5,000
2,500
00
25
50
75
100
Population and
emigration
World PopulationAdapted from G
. Richardson, U of Albany
Presentation Dynamics
-Which loop dominates?
Willin
gn
ess t
oask q
uesti
on
sS
elf
–co
nfi
den
ce
Cla
rify
ing
qu
esti
on
sA
ud
ien
ce
un
ders
tan
din
g
Cla
rity
of
pre
sen
tati
on
Adapted from G
. Richardson, U of Albany
Stocks and Flows
Stocks are accumulations.
–Stocks are increased by i
nfl
ow
sand decreased by o
utf
low
s.
–Link m
ean “add to”or “subtract from”
–Example: Nanomaterialsin business inventory
ou
tflo
w v
alv
ein
flo
w v
alu
e
sin
ks
ou
rce
Sh
ipm
en
tsP
rod
ucti
on
Inven
tory
Adapted from G
. Richardson, U of Albany
SD: Advantages for RA for Nanomaterials
•Examine C
hange over Tim
e (the world is dynamic)
•Account for Feedback (the world is not linear)
•Allo
w for lifecycle RA approach
–birth to death, but also death to birth through feedback
•Consider of complex problems with lim
ited data
–based on m
ix of mental models, literature, theory, data
•Can be used to link natural, social, behavior dim
ensions of risk
analysis
•Assess m
ajor drivers and levers in system
The m
ajority of inform
ation exists
in m
ental models
Forrester 1991
Disadvantages
•Assumes causality through m
ental models
•Untraditional approach to RA (not linear with “risk”at
end
•Models can become complex fairly quickly
•Difficult to link up natural, social, behavior parameters
•Scoping of problem and determ
ining m
odel
boundaries challenging
Our modeling efforts for ENM and
environmental risk
•Draw upon
–Previous uses of SD for health and disease risk m
anagement
(K. Thompson, J. Homer, et al.)
–Previous use of SD for flows of chemicals in the environment
(A. Ford)
•Have the ultim
ate goals of
–Use for public engagement in decision m
aking (K. Stave)
–Identifying policy levers and programmatic needs (G.
Richardson, many others in SD community)
Use for chemical
flows and
environmental
health impacts
A. Ford, WSU, Modeling the Environment
SD role in Public participation
•Visual tool to engage and promote
understanding
•Include public and stakeholders in m
odel
development and policy choices considered
•Consensus and/or dialogue tool
•User-friendly interfaces for policy or
programmatic levers
SD for public participation in environmental decisions
Causal loop diagram of traffic congestion
Stave 2002
Policy lever interface
Stave 2002
Current research
•Explore Risk Analysis for Nanotechnology in the
Environment using SD approaches
•Use nanoZeroValentIron (nZVI) given its intentional
introduction to remediate
–easier initial starting point
•Draw upon DDT m
odel approach
•But also take advantage of wider systems view of risk
perception, scientific knowledge, public attitudes,
funding, regulatory system
•A work that has just begun…
NanoZero ValentIron Background
•nZVIperhaps m
ost widely used nanoparticle
in
environmental remediation
•Treats recalcitrant and toxic contaminants such as
chlorinated hydrocarbons, chromium and arsenic in
groundwater
•Application: nanoscale
particles are injected directly into
aquifer
•Has been used at more than 30 sites
From Sellers 2009
GeoNanoEnviroTech, Inc. 2007
ASR Technologies, Inc. 2009
Steps of the O
ur Modelling
Process
Forrester 1991
Modelin
g Process
1.
Identify the Problem:
How to m
axim
ize nZVIbenefits while m
inim
izing
risks, & respecting social values
2.
Create D
ynamic Hypothesis: map causal
structure of the problem
3.
Form
ulate the Sim
ulation M
odel
4.
Testing
5.
Policy D
esign and Evaluation
NanoZero ValentIron: Background (cont.)
•Compared to granular ZVI particles, Nanoscale
ZVI particles
have a higher reaction rate due to higher surface area
•Increases in particle size lim
it m
obility
•Fate and transport dependent on reagent and aquifer
characteristics
•Lim
ited field and ecological data
•Lim
ited toxicology data-Weisneret al in vitro study showed
oxidative stress response and assim
ilated nZVIin cells (2007)
Key sources for the Physical nZVIModule
•Selle
rs, Kathleen (2009). Nanotechnology and the environment,
ch. 10 Nanoparticle
use in pollu
tion control. Taylor & Francis
Group, LLC
•Watlington, Katherine (August 2005). Emerging
nanotechnologies for site remediation and wastewater
treatm
ent.
•Environmental Protection Agency (October 2008).
Nanotechnology for site remediation fact sheet. U.S. EPA Solid
Waste and Emergency R
esponse
•Mace et al (2006). Nanotechnology and groundwater
remediation: a step forw
ard in technology understanding, W
iley
InterScience
The “high level”systems m
ap
nZVI Particles
Injected
Uptake
Ill Fish
Ill Humans
Knowledge of Cause of
Risk Outcomes for Fish
Knowledge of Cause of
Risk Outcomes for Humans
Perceived
Risk/Benefit Ratio
Social Desirability of
Using nZVI
Feasibility
Regulation Level
Political Support
Affect
Psychometric
InputsTrust in Government,
Industry
Public Funding for
Research
Products on the
Market
Public Knowledge
about nZVI
Scientific Knowledge
about nZVI
Public Familiarity
Media
Actual Risks and
Benefits
The Full DRAFT M
odel
nZVI particles in
water onsite
Ions in
groundwater
onsite
nZVI particles
off-site
ZVI particles
settled out
onsite
Other
byproducts
onsite
Pollution in
groundwater
onsite
Injection
Oxidation
Other reactions
Expected pollution
byproducts onsite
Remediation rxn
Remediation rxn 1
Polluting
Transport
Conglomeration
Off-site
degradation
ZVI degradation
Degradation
Degradation rate
Oxidation rate
Pollution rate
Other compounds
present
Reaction rate
Byproducts
off-site
Byproduct
transport 1Removal rate
nZVI particles
in humans
from offsite
nZVI particles
in fish from
offsite
Offsite uptake in
fish
Offsite uptake in
humans
Ill humans
Dead
humans
Recovered
Humans
Ill fish
Dead fish
Recovered
fish
Knowledge of cause of
risk outcomes for humans
Knowledge of cause of
risk outcomes for fish
Ingestion rate of
fish
Harmful
human
cell/organ
physiological
changes
Human
cell/organ
death
Human
repair/excretion
Harmful fish cell/organ
physiological changes
Fish cell/organ
death Fish
repair/excretion
nZVI particles
in humans from
onsite
nZVI particles
in fish from
onsite
Onsite uptake in
humans
Onsite uptake in
fish
Harmful human cell/organ
physiological changes0
Harmful fish cell/organ
physiological changes0
Human ingestion nZVI
from fish offsite
<nZVI particles in fish
from onsite>
Human dermal
absorption rate
Human inhalation
absorbtion rate
Human
gastro-intestinal
absorbtion rate
Fish absorption
rate
Public knowledge
of nZVI particles
Scientific
knowledge about
nZVI particles
Scientific information
dissemination
Other nano
information
Media publicationnZVI products on
the marketPrivate research and
development
Product data
information
dissemination
Scientific data on
nZVI particles
Publication
Scientific research
General research Social
Desirability of
nZVI technology
Regulation level of
nZVI particles
Cost effectiveness of
nZVI over other
technology
Feasibility of nZVI
technology
Level of political support
for nZVI technology
Public funding for
nZVI technology
Public decision
making
Public familiarity with
nZVI technology
Perceived risk/benefit
ratio of nZVI technology
Framing of
nanotechnology
Framing of
product data
Framing of studies
and results
Other psychometric and attitudinal
factors: gender, race, trust of "expertise",
feeling of personal control, perceptions
of justice
Malleability of judgment
of nZVI technology
Actual human risk
Actual Benefits
Level of trust in government,
science and industry to use
nZVI
Affect: feeling or
emotion about using
nZVI
Actual fish risk
The Physical Module: System
Map
nZVI Particles
Injected
Remediation of
Pollution
Byproducts
nZVI Particles
stay on-site
nZVI Particles
off-site
Uptake in Plants and
Microorganisms
Uptake in Fish
Uptake in
Humans
Ill Humans
Ill Fish
Dead Fish
Dead Humans
Knowledge of Cause of
Risk Outcomes for Fish
Knowledge of Cause of
Risk Outcomes for
Humans
Th
e P
hysic
al
DR
AF
T M
od
el
nZVI particles in
water onsite
Ions in
groundwater
onsite
nZVI particles
off-site
ZVI particles
settled out
onsite
Other
byproducts
onsite
Pollution in
groundwater
onsite
Injection
Oxidation
Other reactions
Expected pollution
byproducts onsite
Remediation rxn
Remediation rxn 1
Polluting
Transport
Conglomeration
Off-site
degradation
ZVI degradation
Degradation
Degradation rate
Oxidation rate
Pollution rate
Other compounds
present
Reaction rate
Byproducts
off-site
Byproduct
transport 1Removal rate
nZVI particles
in humans
from offsite
nZVI particles
in fish from
offsite
Offsite uptake in
fish
Offsite uptake in
humans
Ill humans
Dead
humans
Recovered
Humans
Ill fish
Dead fish
Recovered
fish
Knowledge of cause of
risk outcomes for humans
Knowledge of cause of
risk outcomes for fish
Ingestion rate of
fish
Harmful
human
cell/organ
physiological
changes
Human
cell/organ
death
Human
repair/excretion
Harmful fish cell/organ
physiological changes
Fish cell/organ
death
Fish
repair/excretion
nZVI particles
in humans from
onsite
nZVI particles
in fish from
onsite
Onsite uptake in
humans
Onsite uptake in
fish
Harmful human cell/organ
physiological changes0
Harmful fish cell/organ
physiological changes0
Human ingestion nZVI
from fish offsite
<nZVI particles in fish
from onsite>
Human dermal
absorption rate
Human inhalation
absorbtion rate
Human
gastro-intestinal
absorbtion rate
Fish absorption
rate
Perceived risk/benefit
ratio of nZVI technology
Public Perception of Risk: Systems M
ap
Knowledge of Cause of
Risk Outcomes to Fish
Knowledge of Cause of
Risk Outcomes to
Humans
Perceived Risk/Benefit
Ratio of nZVI
Technology
Scientific
Knowledge about
nZVI
Public Knowledge
about nZVI
Public Familiarity
with nZVI
Actual Human
Risk
Actual Fish
Risk
Feasibility of
Using nZVI
Social Desirability
of Using nZVI
Psychometric
Inputs
Affect
Level of Public Trust in
Government, Industry to
Use nZVI
Malleability of
Judgement
Actual Benefits
of nZVI
The Public Perception M
odule
Knowledge of cause of
risk outcomes for humans
Knowledge of cause of
risk outcomes for fish
Regulation level of
nZVI particles
Feasibility of nZVI
technology
Level of political support
for nZVI technology
Public funding for
nZVI technology
Public familiarity with
nZVI technology
Perceived risk/benefit
ratio of nZVI technology
Other psychometric and attitudinal
factors: gender, race, trust of "expertise",
feeling of personal control, perceptions
of justice
Malleability of judgment
of nZVI technology
Actual human risk
Actual Benefits
Level of trust in government,
science and industry to use
nZVI
Affect: feeling or
emotion about using
nZVI
Actual fish risk
Dead humans
Dead fish
Ill humans
Ill fish
nZVI Particles
injected on-site
Social
desirability of
nZVI
technology
Public knowledge
of nZVI particles
Scientific
knowledge of
nzVI particles
Scientific information
dissemination
Public decision
making
nZVI Products
on the market
Product data
information
dissemination
Other nano
information
Media Publication
The Social Module Systems M
ap: Social, Economic,
Political, Psychometric Inputs
Scientific Knowledge
of nZVI Particles
Public Knowledge of
nZVI Particles
Social Desirability of
nZVI Technology
Perceived Risk/Benefit
Ratio of nZVI
Technology
Level of Trust in
Government, Industry to
Use nZVI
Affect
Feasibility of nZVI
Technology
Political Support
for nZVI
Public Funding for
nZVI Research
nZVI Products on
the Market Regulation Level for
nZVI Particle Use
Public Familiarity
with nZVI Particles
nZVI Particles in
the Media
The Social Module of the M
odel
Public knowledge
of nZVI particles
Scientific
knowledge about
nZVI particles
Scientific information
dissemination
Other nano
information
Media publicationnZ
VI products on
the marketPrivate research and
development
Product data
information
dissemination
Scientific data on
nZVI particles
Publication
Scientific research
General research Social
Desirability of
nZVI technology
Regulation level of
nZVI particles
Cost effectiveness of
nZVI over other
technology
Feasibility of nZVI
technology
Level of political support
for nZVI technology
Public funding for
nZVI technology
Public decision
making
Public familiarity with
nZVI technology
Perceived risk/benefit
ratio of nZVI technology
Framing of
nanotechnology
Framing of
product data
Framing of studies
and results
Other psychometric and
attitudinal factors: gender, race,
trust of "expertise", feeling of
personal control, perceptions of
justice
Malleability of judgment
of nZVI technology
Actual human risk
Actual Benefits
Knowledge of risk
outcomes for humans
Knowledge of risk
outcomes for fish
Level of trust in government,
science and industry to use
nZVI
Affect: feeling or
emotion about using
nZVI
Actual fish risk
Ill Humans
Dead Humans
Ill Fish
Dead fish
nZVI Particles
injected on-site
Next steps
•Engage experts and stakeholders
in revision of model
•Data collection
•Iterate above
•Plot Graphs over time of key stocks
•Identify policy levers
•Iterate above
Nanomaterials
RA and SD: Concluding Thoughts
•Approach to RA should m
atch the dynamic and complex nature of
the technology and environmental pathways
•System D
ynamics should be another set in the RA toolbox
•Relia
nce on shared m
ental model provides opportunity to
engage stakeholders
•Can be done in a data-poor environment
–avoid “paralysis by analysis”
•Action based approach in its quest for policy and programmatic
levers
•Helps identify data gaps
Thank you
•This w
ork was partially supported by the Institute
on the Environment and the N
ational Science
Foundation (NIR
T G
rant SES-0608791)
•Additional questions, comments, colla
borations,
please contact me:
–kuzma007@
umn.edu
–612-625-6337