the use of engineered nanomaterials in environmental remediation: environmental, health, and...
TRANSCRIPT
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The Use of Engineered Nanomaterials
in Environmental Remediation:
Environmental, Health, and
Regulatory Issues
Tennessee Environmental Conference
March 26, 2014
Gregory Nichols, MPH, CPH
Health Research Associate
ORAU
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Outline
• Overview
• Types of materials
• Sites
• Environmental and health concerns
• Regulations
• Scientific and legal gaps
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What is nanotechnology?
• Nanotechnology is the manipulation of matter between 1 and
100 nm
Yokel and MacPhail, 2011
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Soil and groundwater remediation
• The removal of contaminants from environmental media for the protection of human health/environment or for redevelopment
http://en.wikipedia.org/wiki/Environmental_remediationhttp://energy.gov/em/services/site-facility-restoration/soil-groundwater-remediation
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Nanoremediation basics
• Nanoremediation = The application of reactive nanomaterials for transformation and detoxification of pollutants (Karn et al., 2009)
• Nanotechnology is being used across the country at Superfund and other hazardous waste sites
• Introduced as a theoretical approach in 2000– Taken off more than expected
– Still not mainstream, yet
– Has been used at approx. 60 sites around the world
• Shows promise but still relatively untested
• First 15 years focused on application
• Shift towards understanding implications
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Types of materials used
Nanomaterials Examples Remediation Uses
BNPs and zero-valentiron
Ni; Au; Pd/Pt; BNPs; nZVI • Waters• Sediments• Soils• Hydrocarbons
Metal oxides NPs TiO2; ZnO; CeO
Nanometals Ag
Carbonaceous NPs MWCNT; nanoporous activated carbon fibers (ACFs)
• Sorption of metals (Cd; Pb; Cu)
• Sorption of BTX
Nano-clays/zeolites Na6Al6 · Si10 · 12 H2O Sorption/ion exchange for metals
Carbon-based dendrimers
Hyper-branched polymers
PAHs; ultra-filtration of heavy metals
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Sites using nanoremediation
http://www.nanotechproject.org/inventories/remediation_map/
Approximately 30 sites currently using/testing nanoremediation techniques
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Select nanoremediation sites
City, State Contaminant Nanomaterial
Lakehurst, NJ DCE, VC, PCE, TCE, TCA BNP
Bridgeport, OH DCE, VC, TCE Palladium-Silica
Ringwood, NJ Heating oil Nano-Ca
Cape Canaveral, FL TCE EZVI
Santa Maria, CA TCE, DCE Nano-porous Fe
Dayton, OH TCE, PCE nZVI-silica hybrid
Edison, NJ TCA, TCE, DCA, DCE, chloroethane, VC
nZVI
Rochester, NY Methylene chloride; 1,2-DGP; 1,2-DCA
nZVI
Trenton, NJ DCE, VC, PCE, TCE, CCl4; 1,1-DCE, chlorofrom
Fe/Pd
http://www.clu-in.org/download/remed/nano-site-list.pdf
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Environmental Risks
• Uptake of nanoparticles by
– Plants
– Fungi
– Aquatic organisms
– Microbes
– Smaller terrestrial organisms
• Potentially ecotoxic
– Alter soil pH
– Phototoxicity
• Bioaccumulation
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Health Issues
• Occupational
– Respiratory
– Cardiovascular
– Neurological
– Genotoxic
– Hepatic/Renal
• Community/Population
– Recreational/drinking water contamination
– Bioaccumulation
– Perception of risk
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Potential Impact
• “Trojan Horse” effect
• Contaminants could “rebound”
• Free radical creation
• Shape, size, reactivity of particles – complicated
chemistry (lots of unknowns)
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Current Regulations
• No nano-specific regulations exist
• US Agencies are adapting existing regs/guidelines to
nanotechnologies
– DOL/OSHA
• Occupational Safety and Health Act (1970)
• HAZCOM (29 CFR 1910.1200)
– EPA
• Toxic Substances Control Act (1976)
• Clean Water Act (1970)
• Resource Conservation and Recovery Act (1976)
• Safe Drinking Water Act (1974)
• Clean Air Act (1970)
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Current Regulations (cont’d)
• Europe
– Registration, Evaluation, Authorization, and Restriction of
Chemicals (REACH)
• Global
– Organization for Economic Cooperation and Development
(OECD)
– International Organization for Standardization (ISO)
– World Health Organization (WHO) guidelines
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Research needs
• Continued remediation technology development
– “Smart” nanoparticles
– Detection equipment (tracking/monitoring)
– Delivery systems
• Tools for characterizing complex subsurface
conditions
• Biological assessment capabilities
– Modeling
– Cytotoxic assays
• Health/Environmental studies
– Nanomaterial life-cycle
– Risk management
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Recommended actions
• Development of standard “best – practices”
• Standard protocol for site characterization
• Registry/medical surveillance for workers
• Database(s) for tracking nanomaterial
types/quantities
• Protocol for verifying cleanup of spent nanomaterials
needs to be developed
• Sharing of human health/ecological data
• Long-term studies of ecosystem impact
• State regulations/updated federal statutes
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Summary
• While nanoremediation appears to be a very
promising technology, many questions remain
unanswered
– Chemical Fate and transport
– Toxicity/Human health
– Containment/Recovery of materials
– Ecotoxicity
– Community health
• A cautious approach is recommended
• Cooperation between industry, academia, and
government is crucial
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Thank You!
Gregory Nichols, MPH, CPH
Health Research Associate
ORAU
Occupational Exposure and Worker Health Programs
Ph: (865) 576-3144