Embracing C

omplexity and Change:

Systems Approaches to Risk

Analysis for Nanomaterials

Pro

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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