Identifying & Regulating
Environmental Impacts
of Nanomaterials
NSF NER 0508347
PIs: Nathan Swami, Michael Gorman
Students: Ahson Wardak, Shilpa
Deshpande, Emma Fauss
Rationale
To realize the market potential of nanotechnology,
uncertainties need to be characterized through
upstream identification of risks & opportunities.
Some uncertainties with nanotechnology:
„ No real-time monitoring & protection technology
„ Toxic effects at cellular or tissue levels
„ Classification & Nomenclature for Regulation
„ System-level: Cascading, Interactive, Embedded
and Autonomous System effects
2
Research Goals
„
Framework to identify the risks and impacts:
… Estimating
risks from a study of potential hazards
and exposure scenarios
… Including Regulatory & Knowledge Gaps in risk
identification strategy
Methodology to weigh benefits against risks
„ Pathways to risk-based regulation rather than
list-based regulation
„
3
Methodology: Scenario Analysis & Expert Elicitation
Knowledge
Risk
Triggers
Gaps
Regulation
Exposure
Scenarios
Update
Expert
Elicitation
Hazard
Real
Risks
Nano product
Information
Exposure
Weighted
against
Perceptive Risks
General Public
(from prior surveys)
Scenario Analysis
Phase
Expert Elicitation
Phase
Multicriteria
Analysis, HHM
Risk Identification
And Mapping
4
Continuum of Nanotechnology
Regulation Proposals
Regulatory Continuum
Normatively Ideal or
Adaptive
Restrictive
Calls for a
Moratorium (ETC
Group)
Treatment of
Nanomaterials as
New Substances
(NRDC, et. al.)
Prohibition on Use
of Free
Nanoparticles
(UK Royal Society)
Voluntary
Standards of
Care (ED)
Permissive
No Special State
of Regulations (Present State of
Regulatory
Posture)
Foresight
Guidelines (The
Foresight
Nanotech
Institute)
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Regulatory Gaps
Nano-products likely to fall through regulatory gaps due to
classification and nomenclature issues
• Which regulatory gaps apply to which nano-products
• To what extent, and where in the product life cycle
• Weight the risks that arise from regulatory gaps
Life Cycle Stage
Relevant Risk Triggers
R & D, Manufacturing and Application stage
TSCA: R&D, Test marketing,
Low volume exemption
Possible products
Products that contain carbon nanotubes (Field
Emission Displays), perhaps tennis rackets
FDA: Regulatory centers
Sunscreen, Toothpaste, Food Supplement,
FDA Nomenclature: Device or a Drug? MRI contrast agent
FIFRA: Pesticidal or
antibacterial effects?
Antibacterial - harm useful bacteria in
the environment or the human body? Toothpaste, Air freshener
End-of-Life & Disposal stage
RCRA: classification under
Air freshener spray, Battery,
RCRA?
Multiple Disposal Pathways
MRI contrast agent, Field emission display
Transporting stage
New product - new nano-application or Battery, MRI contrast agent, Field emission
HMTA
performance enhancement?
display
Long Term Environmental Site Implications stage
CERCLA (Superfund): Long
Dispersibility, Photoactive behavior or Air Freshener, Battery, Racquet,
term environmental, health risk Catalytic Property, Antibacterial
Field Emission display
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7
Case Study: Carbon
Nanotubes and the Low
Volume Exemption
„
„
„
Life Cycle Stage: Manufacture
Regulatory Gap: Under TSCA, LVE limits regulation of facilities
producing <10,000 kg/year
Scenario:
…
…
„
About 44 carbon nanotube producers (Cientifica), and about 100 metric tons
produced per year (UK Royal Society)
“A 40 inch computer display uses one-sixth of a gram of carbon nanotube
powder (roughly 10,000 nanotubes) (Mann 2004). If all 25 metric tons of
carbon nanotubes going to electron emission applications (estimated above)
are used for computer displays, they would enter into 150 million displays.”
Implications:
…
…
Potential environmental impacts are widespread with no attention to risk.
Nanomaterials change the risk assessment paradigm. Mass does not
correlate risk or exposure.
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Risk Identification for Air Fresheners
Product Information: 20-50 nm silver nanoparticles in polymer
matrix with antibacterial properties (used as spray)
High-risk scenarios: Inhalation and air release during use,
water entrainment during disposal
Nano-property risk triggers: Easy bio-availability, anti-bacterial
property, ease of dispersion, affect on susceptible populations
Hazard vs Exposure scenarios
Exposure
5
3
Use Inhalation
Disposal Inhalation
Disposal Air
release
1
Use Skin
absorption
Use Air release
Disposal water entrainment
Use Ingestion,
water entrainment
Disposal ingestion
Disposal Skin absorption
1
3
Hazard
5
Intersection Scenarios:
• Wider bio-availability
during air-release or
water entrainment
• Anti-bacterial effects
outside product cycle
•Susceptible Population
(respiratory problems)
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Risks from cross-section of products
•Relative risks higher for sunscreens, toothpastes, and air
fresheners based on number and weights of both ‘high
hazard’ and ‘high exposure’ scenarios
•Food supplements and MRI contrast agents pose some
significant scenarios for high-hazard, but few scenarios for
high exposure
Hazard vs Exposure
6
Sunscreen
Hazard
5
Air freshener
4
Toothpaste
High risk
3
Medium risk
2
Low risk
1
Battery
Display
0
0
1
2
Food supplement
Racquet
MRI contrast agent
3
4
5
6
Risk higher for products
where Nanoparticles
can be disengaged
from the matrix or
composite to which
they are bound
Exposure
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Challenges & Opportunities
„
Risk:
… Including
regulatory and knowledge gaps in framework
… Criteria to weigh risks arising from various sources
„
Regulatory:
… Statutes
regulate products not technologies
… Dispersed through multiple agencies
„
Toxicology:
… Need
standardized methods to collect toxicology data for
application within risk context
„
„
Risk versus benefit analysis
Hazard communication to decrease exposure
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Publications
(In Press). Environmental Regulatory Implications
for Nanomaterials under the Toxic Substances
Control Act (TSCA), IEEE Technology & Society
„ The Product Life Cycle and Challenges to
Nanotechnology Regulation, Nanotechnology Law
and Buiness, Vol 3, Issue 4.
„ (Submitted). Identification of Risks in the Life-Cycle
of Nanotechnology-Based Products, Journal of
Industrial Ecology.
„ Conference Presentations at MRS Fall 2005, NSTI
Summer 2007
Acknowledgements: Student internships at
Wilson Center, Rice University’s CBEN
„
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