Environmental Applications and Implications of Nanotechnology

Transcription

1 Environmental Applications and Implications of Nanotechnology Association of State and Territorial Solid Waste Management Officials Annual Meeting Baltimore, MD October 23, 2008 Marti Otto Office of Superfund Remediation and Technology Innovation U.S. Environmental Protection Agency Washington, D.C

2 Notes Reference herein to any specific commercial product, process, or service by trademark, manufacturer, or otherwise does not imply its endorsement, recommendation, or favoring by the U.S. Government or any agency thereof. The views and opinions expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof. Special acknowledgement is given to the staff of the United States Environmental Protection Agency s Offices of Air and Radiation; Prevention, Pesticides, and Toxic Substances; Research and Development; Solid Waste and Emergency Response; and Water, who supplied information for this presentation. 2

3 Outline Background Opportunities and Challenges USEPA and Nanotechnology Research Outreach/Programs 3

4 Background: Nanotechnology 4

5 The ultimate goal of nanotechnology is to build essentially anything from scratch, atom by atom Nanotechnology is The understanding and control of matter at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications. Fly ash ~ µm Red blood cells with white cell ~ 2-5 µm DNA ~2 nm wide Size of a Nanometer One billionth (10-9 ) of a meter Atoms of silicon spacing ~tenths of nm 1 nm = 10-9 m 5

6 Sources of Nanomaterials Anthropogenic Engineered Carbon-based Nanotubes, Fullerenes Metal Oxides Quantum Dots Nanotubes Nanowires Dendrimers Incidental Particles from: Combustion Industrial Processes Vehicles Construction Natural Particles from: Plants, Trees Oceans, other water bodies Erosion Dust 6

7 Properties of Nanoscale Materials Chemical reactivity of nanoscale materials may differ from macroscopic form p2library.nfesc.navy.mil Vastly increased surface area per unit mass, e.g., upwards of 100 m 2 per gram Quantum size effects result in unique mechanical, electronic, photonic, and magnetic properties of nanoscale materials New chemical forms of common chemical elements, e.g., fullerenes, nanotubes of carbon, titanium oxide 7

8 Uses of Nanomaterials TiO 2 ZnO MATERIAL Au, Fe, Ag CeO 2 / Ce 2 O 3 ZrO 2 Quantum dots CdSe/ZnS/InAs/I np/ingap USE Pigments, UV-absorber, catalyst Polymer filler, UV-absorber Remediation, clothing Catalyst (cars), fuel additive Ceramic, catalyst support Medical imaging, drug delivery 8

9 Consumer Products Self-cleaning glass, ceramics, and metals Stain-free clothing and mattresses Lighter weight, stronger materials Automobile bumpers, tennis racquets More efficient, cheaper catalytic converters on cars Longer lasting tires and tennis balls Improved dental-bonding/filling materials New types of burn and wound dressings Impermeable materials for food packaging 9

10 Nanotechnology Consumer Products Inventory 10

11 Opportunities and Challenges 11

12 Environmental Opportunities Pollution prevention Treatment Remediation Sensors/detection Energy Other 12

13 Environmental Challenges Potential toxicity Potential exposure Fate, transport, transformation Mobility and persistence Bioavailability, bioaccumulation Critical metric: particle size/number, morphology, surface area, functionalization 13

14 USEPA and Nanotechnology 14

15 EPA s Interest in Nanotechnology Potential for improved environmental protection Clean up past environmental problems Improve present processes Prevent future environmental problems Potential to adversely affect human health or the environment Potential impacts for regulatory responsibilities Proactive approach for managing emerging technologies 15

16 Nanotechnology and USEPA Programs Pesticides Toxic Substances Air and Radiation Water Waste 16

17 Pesticides Office of Pesticides Programs (OPP) requires data submissions for pesticide products and conducts risk assessments on environmental, human health and safety data OPP focuses on three major types of pesticides: agricultural, antimicrobials, and biopesticides. 17

18 Pesticides, Cont. OPP s current approach is to consider a nanoproduct in a pesticide to be a new pesticide active ingredient; therefore, new data would be required The nanoproduct would be considered a new active ingredient unless the company showed that the nanosized form is toxicologically similar to the larger form OPP will consider nanoproducts on a case-by case basis and will require product-specific data. There have been inquiries concerning the process for registering a pesticide that contains nanomaterials; but, OPP has no active cases for registration under consideration 18

19 Toxic Substances Many nanoscale materials (NMs) are chemical substances as defined by the Toxic Substances Control Act (TSCA) NMs not on the TSCA Inventory are new chemicals and a Pre-Manufacture Notice (PMN) is required before commencement of manufacture numerous PMNs have been received in the past 2 years. There is presently no similar requirement for NMs that are existing chemicals, i.e. already on the TSCA inventory TSCA definition of new chemical based on molecular identity, not on other characteristics 19

20 Toxic Substances, Cont. In January 2008, EPA announced a Nanoscale Materials Stewardship Program (NMSP) under the Toxic Substances Control Act (TSCA) to gather and develop information on engineered chemical nanoscale materials. The program calls on manufacturers, importers, processors, and users of engineered nanoscale materials to report to EPA key information about these materials within six months (Note that TSCA normally would allow entry into commerce without such notification for existing chemicals) EPA will also work with manufacturers, importers, processors and users of nanoscale materials to develop test data to provide a scientific basis for assessing the hazards, exposures, and risks of nanoscale materials. The program also encourages the use of risk management practices 20

21 Toxic Substances, Cont. "Pollution Prevention through Nanotechnology Conference" Held September 25-26, 2007 Was a forum to exchange ideas and information on using nanotechnology to develop new ways to prevent pollution Included representatives from industry, academia, non-governmental organizations, and government Included three major areas: Products: Less toxic, less polluting, and wear-resistant Processes: More efficient and waste-reducing Energy and Resource Efficiency: Processes and products that use less energy and fewer raw materials because of greater efficiency Featured discussions of nanotechnology life-cycle considerations and the responsible development of nanotechnology Details at OPPT is planning to hold a similar conference on an international scale in Fall The potential scope of the conference includes energy applications, such as solar panels and batteries, as well as lighting, insulation, catalysis, and water treatment and purification. 21

22 Air and Radiation Several authorities under the Clean Air Act could be available, depending on the properties and health effects of nanomaterials The hazardous air pollutant program is source categoryspecific. Several programs under the Act may have coincidental impacts on the emissions of nanomaterials (e.g., the fine particle ambient air quality standards and emission standards that require the capture and control of emissions of particles, metals, or other substances that may appear in nano form) No decision has been made whether EPA ought to address nanomaterials through an ultra-fine particle standard, listing and regulation as toxic air pollutants, or address nanomaterials through some other mechanism. The Office of Radiation and Indoor Air is preparing a report on the potential applications of nano-enabled technologies for environmental remediation of sites contaminated with radionuclides 22

23 Water Learning more about nanomaterials to judge whether they should be considered emerging contaminants. If that determination were made, the next step would be to develop a risk assessment Working with EPA s Office of Research and Development and other offices on analytical methods to quantify nanomaterials in environmental media 23

24 How Does Nanotechnology Affect the USEPA Waste Programs? 24

25 Application: Nanotechnology for Site Remediation Potential applications include use of nanoscale zero-valent iron (NZVI) particles to clean up source areas of groundwater contamination Contaminants - Chlorinated hydrocarbons - Metals? - Pesticides? Wei-Xian Zhang, Lehigh University Over 25 field-scale and full-scale studies 25

26 Potential Benefits of Iron Nanoparticles Small particle size ( nm) Smaller size makes it more flexible penetrates difficult to access areas High surface area to weight ratio (~30 m 2 /g) Highly reactive: readily reduces contaminants Direct injection into aquifers Faster cleanups 26

27 Potential Issues Potential rebound of contaminants after injection Iron Passivation Agglomeration reducing effective distribution Lack of understanding - abiotic v. biotic degradation Inability to project particle movement 27

28 How Does Nanotechnology Affect the USEPA Waste Programs? Applications: Protecting Human Health and the Environment Potential environmental implications: Toxicity? Exposure? Bioaccumulation? Persistence? Transformation? 28

29 Risk Assessment: A Life-Cycle Approach 29

30 Nanotechnology Research 30

31 National Nanotechnology Initiative Federal Nanotechnology R&D in the U.S. is coordinated by the NNI 2001: NNI created as a federal initiative 2003: 21st Century Nanotechnology Research and Development Act The goals of the NNI are to: Maintain a world-class R&D program to realize the full potential of nano Facilitate transfer of new technologies into products for economic growth Develop education, workforce, and infrastructure/ tools to advance nano Support responsible development of nano 31

32 Nanotechnology Environmental, Health, and Safety (EHS) Research US government Other governments International organizations Organisation for Economic Co-operation and Development (OECD) International Organization for Standardization (ISO) Universities Private sector Some states, localities 32

33 EPA Extramural Research on Nanotechnology or Nanomaterials Applications: Green manufacturing Contamination remediation Sensors for environmental pollutants Waste treatment Small Business Innovation Research Implications Detection and Monitoring Environmental and Human Health Effects Biocompatibility and Toxicity Life Cycle Approach Newly formed Centers for the Environmental Implications of Nanotechnology (CEIN) at Duke University and UCLA 33

34 EPA s Nanomaterial Research Strategy Draft research strategy released in February 2008 Expert external peer meeting was held in April 2008 Final document expected in 2008 In the near term, EPA will focus on: - Environmental fate, transport, transformation - Exposure - Monitoring and detection methods - Effects assessment methods 34

35 Outreach/Programs/Products 35

36 Outreach/Programs/Products Superfund fact sheet on nanotechnology for site remediation and information on test sites Series of Internet Seminars on Nanotechnology and Superfund Issues area on CLU-IN website EPA nanotechnology websites ORD/NCER: OPPT: OSWER: 36

37 Outreach/Programs/Products EPA ORD Nanomaterial Research Strategy: EPA Nanotechnology White Paper released Feb 15, EPA Nanomaterials Stewardship Program 37

38 Outreach/Programs/Products Workshops/Conferences on Environmental Applications and Implications of Nanotechnology Coming Soon EPA nanotechnology web portal International Conference on Implications and Applications of Nanotechnology (UMass, Amherst, June 2009) 38

39 Take-Home Messages Nanotechnology is a very powerful new mixture of disciplines that is changing our industries and our lives Applications are currently being developed and implemented, including promising environmental technologies (e.g., innovative applications for waste site remediation) More research is needed on potential implications of nanotechnology and nanomaterials 39

40 For More Information Marti Otto USEPA Office of Superfund Remediation and Technology Innovation