Office of Research and Development
Assessing the Risks of Nanomaterials
J. Michael Davis, Ph.D.Senior Science Advisor
National Center for Environmental AssessmentOffice of Research and Development
U.S. Environmental Protection AgencyResearch Triangle Park, NC 27711
Auditing RoundtablePhoenix, Arizona – January 7, 2008
Office of Research and Development
Outline
Overview of organizations and activities relevant to nanotechnology Environmental, Health, and Safety issues
EPA Case Studies for development of a Comprehensive Environmental Assessment Research Strategy for Nanomaterials
Office of Research and Development
Federal Context for Nanotechnology
President’s Office of Science and Technology Policy (OSTP)
National Science and Technology Council (NSTC)
Nanoscale Science, Engineering, and Technology Subcommittee (NSET)
National Nanotechnology Initiative (NNI)
Nanotechnology Environmental and Health Implications Working Group (NEHI)
Office of Research and Development
National Nanotechnology Initiative
• National Nanotechnology Initiative (NNI ) (www.nano.gov):
–coordinates R&D of 20+ federal agencies– funds university research–supports commercial development–Note: Applications funding >>> Implications funding
• Nanotechnology Environmental and Health Implications Working Group (NEHI )–coordinating role for federal EHS research– “Environmental, Health, and Safety Research Needs for Engineered
Nanoscale Materials” (2006) (http://www.nano.gov/NNI_EHS_research_needs.pdf)
Office of Research and Development
Federal Nanotechnology R&D
NIOSH
NIST
NSF
USDA
et al.
DOD
DOE
EPA
FDA
NASA
NIEHS
Office of Research and Development
Other Activities Related to
Nanotechnology
Environmental Defense - DuPont Nano Risk Framework (http://nanoriskframework.com)
Woodrow Wilson Center (www.wilsoncenter.org/nano)
International Council on Nanotechnology / Center for Biological and Environmental Nanotechnology (Rice University) (http://icon.rice.edu)
Organisation for Economic Co-operation and Development (OECD) (http://www.oecd.org/env/nanosafety/)
European Union (EU) (http://cordis.europa.eu/nanotechnology/)
United Kingdom Royal Society (http://www.nanotec.org.uk/)
ISO / ANSI / ASTM
Office of Research and Development
OECD Program on Safety of Manufactured Nanomaterials
• Objective: promote international cooperation in EHS-related aspects of manufactured nanomaterials
• Workgroups:–Development of EHS research database–Research strategies–Safety testing of representative materials–Testing guidelines–Cooperation on voluntary and regulatory efforts–Cooperation on risk assessments and exposure
measurements
Office of Research and Development
EPA Organizational and Regulatory Context
for Nanotechnology Issues
• Office of Air and Radiation (OAR)–Clean Air Act (CAA)
• Office of Prevention, Pesticides, and Toxic Substances (OPPTS)–Toxic Substances Control Act (TSCA)–Federal Insecticide, Fungicide and Rodenticide Act (FIFRA)
• Office of Solid Waste and Emergency Response (OSWER)–Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA)–Resource Conservation and Recovery Act (RCRA)
• Office of Water (OW)–Clean Water Act (CWA)
• Office of Research and Development (ORD)• Science Policy Council / Nanotechnology Workgroup
Office of Research and Development
EPA Regulatory Authorities
• Toxic Substances Control Act (TSCA)–Pre-Manufacture Notice (PMN)–Significant New Use Rule (SNUR)–Nanoscale Materials Stewardship Program
(http://www.epa.gov/oppt/nano/nmspfr.htm)Stewardship Program Concept PaperInformation Collection RequestTSCA Inventory Approach Paper
• Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)–Pesticide Registration: Clarification for Ion Generating
Equipment(http://www.epa.gov/oppad001/ion_gen_equip.htm)
Office of Research and Development
Selected EPA Efforts Related to
Nanotechnology R&D
• STAR grants (www.epa.gov/ncer/nano)
• NSF/EPA rfp for a Center for the Environmental Implications of Nanotechnology http://www.nsf.gov/pubs/2007/nsf07590/nsf07590.htm
• ORD Nanomaterials Research Strategy (Draft)
• EPA Nanotechnology White Paper (2007) www.epa.gov/osa
• EPA Nanomaterial Case Studies for Comprehensive Environmental Assessment
Office of Research and Development
EPA Nanotechnology White Paper (Feb. 2007):
Key Recommendations
• Environmental applications research
• Risk assessment research–Physicochemical characterization–Environmental fate–Environmental detection and analysis–Potential releases and human exposure–Human health effects assessment–Ecological effects assessment–Case studies
• Pollution prevention, stewardship, sustainability
• Collaboration and leadership
• Intra-agency workgroup
• Training
Office of Research and Development
Comprehensive Environmental Assessment (CEA)
CEA ≈ LC + RA
LC: Product Life Cycle framework
RA: Risk Assessment paradigm
See: Davis, J. M. “How to assess the risks of nanotechnology: learning from past experience”J. Nanosci. Nanotechnol.7(2): 402-409, 2007
Office of Research and Development
Feedstocks Manufacturing Distribution
Storage Use Disposal
Product Life Cycle
Office of Research and Development
Risk Assessment
Dose-ResponseAssessment
Hazard Identification
RiskCharacterization
ExposureAssessment
Office of Research and Development
Secondary contaminants
Primary contaminants
Fate & Transport
Air
Water
Soil
Food web
Feedstocks
EffectsExposureEnvironmental Pathways
Life Cycle Stages
Human Health
Use
Disposal
Storage
Biota
Human populations
Distribution
Eco-systemsManufacture
Comprehensive Environmental Assessment
(CEA)
Office of Research and Development
CEA Features
• Qualitative > quantitative
• Comparative:–Alternative choices –Risks vs. benefits
• Guidance to risk managers:–Highlights trade-offs–Focus for monitoring, mitigation–Adaptive management
• Identifies:– Information gaps–Research priorities
Office of Research and Development
Process
• Focus on draft case studies
• Obtain variety of technical & stakeholder perspectives
• Use expert judgment methods
• Repeat periodically
Office of Research and Development
Case Studies
• EPA Nanotechnology White Paper (2007) recommendation
• Goal: identify & prioritize research needed for comprehensive environmental assessment of nanomaterials
• Selected classes of nanomaterials:–Nanoscale titanium dioxide (nano-TiO2) –Single-wall carbon nanotubes (SWCNT)
Office of Research and Development
Case Studies (cont’d.)
• Specific Applications within Classes of Nanomaterials:–CS#1 nano-TiO2 for water treatment–CS#2 nano-TiO2 in sunscreen–SWCNT application(s) not yet determined
• Note: Case Studies are notcompleted assessments
Office of Research and Development
Summary of Acute nano-TiO2 Aquatic Toxicity Tests
LNAEC50EU standard algal assay (Hunde-Rinke and Simon 2006)
100 nm anatase(Hombikat)
Acute Algal toxicity
M
(harmful according to EC)
32-44 mg/LEC50EU standard algal assay (Hunde-Rinke and Simon 2006)
25 nm P25 (~80% anatase: 20% rutile)
Acute Algal toxicity
L>100 mg/LLC50 (96h)OECD 203 (Warheit et al. 2007b)140 nm 79% rutile: 21% anatase
Acute fish toxicity test
M16 ± 6 to 61 ± 9 mg/L
EC50 (72h-growth)
OECD 201 (Warheit et al. 2007b)380 nm rutileAcute algal toxicity
M21 ± 5 to 87 ± 4 mg/L
EC50 (72h-growth)
OECD 201 (Warheit et al. 2007b)140 nm 79% rutile: 21% anatase
Acute algal toxicity
L>100 mg/LEC50 (48h)OECD 202 (Warheit et al. 2007b)140 nm 79% rutile: 21% anatase
Acute aquatic invertebrate (daphnids)
LNAEC50OECD 202 (Wiench et al. 2007)unspecified nano-TiO2Acute aquatic invertebrate
(daphnids)
LNA LC50 (48 hr)EPA 48h tox test (Lovern and Klaper 2006)sonicated >100 nm anatase
Acute aquatic invertebrate (daphnids)
M2.0 mg/L NOECEPA 48h tox test (Lovern and Klaper 2006)THF-30 nm anataseAcute aquatic invertebrate (daphnids)
M5.5 mg/L LC50 (48 hr)EPA 48h tox test (Lovern and Klaper 2006)THF 20-30 nm anatase
Acute aquatic invertebrate (daphnids)
EPA / OPPT Hazard RankingValueEndpointStudyMaterial TEST
Office of Research and Development
CEA Case Study – Water Treatment
Scenario A
Secondary contaminants
Primary contaminants
Fate & Transport
Feedstocks
EffectsExposureEnvironment Pathways
Life Cycle Stages
Human Health
Food webUse
Disposal
SoilStorage
Aggregate
Cumulative
WaterDistribution
Eco-systemsAirManufacture
Office of Research and Development
Secondary contaminants
Primary contaminants
Fate & Transport
Feedstocks
EffectsExposureEnvironment Pathways
Life Cycle Stages
Human Health
Food webUse
Disposal
SoilStorage
Respiratory
Oral
Dermal
Injection
WaterDistribution
Eco-systemsAirManufacture
CEA Case Study – Water Treatment
Scenario B
Office of Research and Development
Current Status / Next Steps
• Currently:
–Draft CS#1 (water treatment) in limited external review and development
–Draft CS#2 (sunscreen) in review by internal workgroup
• Planned:
–Public comment / input
–Workshop
–Report (Comprehensive Research Strategy)
