EPA 100/B-07/001 | February 2007 www.epa.gov/osa Nanotechnology White Paper Office of the Science Advisor Science Policy Council EPA 100/B-07/001 February 2007 U.S. Environmental Protection Agency Nanotechnology White Paper Prepared for the U.S. Environmental Protection Agency by members of the Nanotechnology Workgroup, a group of EPA’s Science Policy Council Science Policy Council U.S. Environmental Protection Agency Washington, DC 20460 ii EPA Nanotechnology White Paper DISCLAIMER This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication and distribution. Mention of trade names or commercial products does not constitute endorsement of recommendation for use. Notwithstanding any use of mandatory language such as "must" and "require" in this document with regard to or to reflect scientific practices, this document does not and should not be construed to create any legal rights or requirements. Cover Images: Left: Computer images of various forms of carbon nanotubes. Images courtesy of Center for Nanoscale Materials, Argonne National Laboratory Right: Computer image of a dendrimer. Image courtesy of Dendritic NanoTechnologies, Inc. Title Page Image: Computer image of a C-60 Fullerene. Laurence Libelo, U.S. EPA. EPA Nanotechnology White Paper iii Nanotechnology White Paper Workgroup Co-Chairs Jeff Morris Jim Willis Office of Research and Development Office of Prevention, Pesticides and Toxic Substances Science Policy Council Staff Kathryn Gallagher Office of the Science Advisor Subgroup Co-Chairs External Coordination Ecological Effects Risk Management Steve Lingle, ORD Anne Fairbrother, ORD Flora Chow, OPPT Dennis Utterback, ORD Tala Henry, OPPTS Vince Nabholz, OPPTS EPA Research Strategy Human Exposures Converging Technologies Barbara Karn, ORD Scott Prothero, OPPT Nora Savage, ORD Nora Savage, ORD Risk Assessment Environmental Fate Pollution Prevention Phil Sayre, OPPTS Bob Boethling, OPPTS Walter Schoepf, Region 2 Laurence Libelo, OPPTS John Scalera, OEI Physical-Chemical Environmental Detection and Sustainability and Society Properties Analysis Diana Bauer, ORD Tracy Williamson, OPPTS John Scalera, OEI Michael Brody, OCFO Richard Zepp, ORD Health Effects Statutes, Regulations, and Public Communications Deborah Burgin, OEI Policies and Outreach Kevin Dreher, ORD Jim Alwood, OPPT Anita Street, ORD iv EPA Nanotechnology White Paper Workgroup Members Suzanne Ackerman, OPA Y’Vonne Jones-Brown, OPPTS Kent Anapolle, OPPTS Edna Kapust, OPPTS Fred Arnold, OPPTS Nagu Keshava, ORD Ayaad Assaad, OPPTS David Lai, OPPTS Dan Axelrad, OPEI Skip Laitner, OAR John Bartlett, OPPTS Warren Layne, Region 5 Sarah Bauer, ORD Do Young Lee, OPPTS Norman Birchfield, OSA Virginia Lee, OPPTS John Blouin, OPPT Monique Lester, OARM, on detail to OIA Jim Blough, Region 5 Michael Lewandowski, ORD Pat Bonner, OPEI Bill Linak, ORD William Boyes, ORD David Lynch, OPPTS Gordon Cash, OPPTS Tanya Maslak, OSA intern Gilbert Castellanos, OIA Paul Matthai, OPPT Tai-Ming Chang, Region 3 Carl Mazza, OAR Paul Cough, OIA Nhan Nguyen, OPPTS Lynn Delpire, OPPTS Carlos Nunez, ORD John Diamante, OIA Onyemaechi Nweke, OPEI Christine Dibble, OPA Marti Otto, OSWER Jeremiah Duncan, AAAS fellow, OPPTS Manisha Patel, OGC Thomas Forbes, OEI Steve Potts, OW Conrad Flessner, OPPTS Mary Reiley, OW Jack Fowle, ORD Mary Ross, OAR Elisabeth Freed, OECA Bill Russo, ORD Sarah Furtak, OW Mavis Sanders, OEI Hend Galal-Gorchev, OW Bernie Schorle, Region 5 David Giamporcaro, OPPTS Paul Solomon, ORD Michael Gill, ORD liaison for Region 9 Timothy Taylor, OSWER Collette Hodes, OPPTS Maggie Theroux-Fieldsteel, Region 1 Gene Jablonowski, Region 5 Stephanie Thornton, OW Lee Hofman, OSWER Alan Van Arsdale, Region 1 Joe Jarvis, ORD William Wallace, ORD Barb Walton, ORD EPA Nanotechnology White Paper v Table of Contents FOREWORD ................................................................................................................................................... VIII ACKNOWLEDGMENTS.................................................................................................................................. IX ACRONYMS.........................................................................................................................................................X EXECUTIVE SUMMARY...................................................................................................................................1 1.0 INTRODUCTION ...........................................................................................................................................4 1.1 PURPOSE ........................................................................................................................................................4 1.2 NANOTECHNOLOGY DEFINED ........................................................................................................................5 1.3WHY NANOTECHNOLOGY IS IMPORTANT TO EPA.......................................................................................13 1.4 NATIONAL AND INTERNATIONAL CONTEXT.................................................................................................14 1.5 WHAT EPA IS DOING WITH RESPECT TO NANOTECHNOLOGY .....................................................................18 1.6 OPPORTUNITIES AND CHALLENGES..............................................................................................................21 2.0 ENVIRONMENTAL BENEFITS OF NANOTECHNOLOGY................................................................22 2.1 INTRODUCTION ............................................................................................................................................22 2.2 BENEFITS THROUGH ENVIRONMENTAL TECHNOLOGY APPLICATIONS.........................................................22 2.3BENEFITS THROUGH OTHER APPLICATIONS THAT SUPPORT SUSTAINABILITY .............................................24 3.0 RISK ASSESSMENT OF NANOMATERIALS.........................................................................................29 3.1 INTRODUCTION ............................................................................................................................................29 3.2 CHEMICAL IDENTIFICATION AND CHARACTERIZATION OF NANOMATERIALS ..............................................31 3.3 ENVIRONMENTAL FATE OF NANOMATERIALS..............................................................................................32 3.4ENVIRONMENTAL DETECTION AND ANALYSIS OF NANOMATERIALS ...........................................................40 3.5 HUMAN EXPOSURES AND THEIR MEASUREMENT AND CONTROL ................................................................42 3.6 HUMAN HEALTH EFFECTS OF NANOMATERIALS..........................................................................................52 3.7 ECOLOGICAL EFFECTS OF NANOMATERIALS................................................................................................58 4.0 RESPONSIBLE DEVELOPMENT .............................................................................................................63 4.1 RESPONSIBLE DEVELOPMENT OF NANOSCALE MATERIALS .........................................................................63 4.2 PROGRAM AREAS.........................................................................................................................................65 4.3 ENVIRONMENTAL STEWARDSHIP .................................................................................................................68 5.0 EPA’S RESEARCH NEEDS FOR NANOMATERIALS..........................................................................70 5.1 RESEARCH NEEDS FOR ENVIRONMENTAL APPLICATIONS ............................................................................70 5.2 RESEARCH NEEDS FOR RISK ASSESSMENT...................................................................................................72 6.0 RECOMMENDATIONS ..............................................................................................................................82 6.1RESEARCH RECOMMENDATIONS FOR ENVIRONMENTAL APPLICATIONS ......................................................82 6.2 RESEARCH RECOMMENDATIONS FOR RISK ASSESSMENT.............................................................................83 6.3 RECOMMENDATIONS FOR POLLUTION PREVENTION AND ENVIRONMENTAL STEWARDSHIP.........................89 6.4 RECOMMENDATIONS FOR COLLABORATIONS...............................................................................................90 6.5 RECOMMENDATION TO CONVENE AN INTRA-AGENCY WORKGROUP...........................................................91 6.6 RECOMMENDATION FOR TRAINING..............................................................................................................91 6.7 SUMMARY OF RECOMMENDATIONS .............................................................................................................92 7.0 REFERENCES ..............................................................................................................................................93 APPENDIX A: GLOSSARY OF NANOTECHNOLOGY TERMS.............................................................107 APPENDIX B: PRINCIPLES OF ENVIRONMENTAL STEWARDSHIP BEHAVIOR..........................110 APPENDIX C: EPA’S NANOTECHNOLOGY RESEARCH FRAMEWORK..........................................111 APPENDIX D: EPA STAR GRANTS FOR NANOTECHNOLOGY ..........................................................113 vi EPA Nanotechnology White Paper APPENDIX E: LIST OF NANOTECHNOLOGY WHITE PAPER EXTERNAL PEER REVIEWERS AND THEIR AFFILIATIONS ..................................................................................................................................119 EPA Nanotechnology White Paper vii Table of Figures FIGURE 1. DIAGRAM INDICATING RELATIVE SCALE OF NANOSIZED OBJECTS......................................................6 FIGURE 2. GALLIUM PHOSPHIDE (GAP) NANOTREES............................................................................................7 FIGURE 3. COMPUTER IMAGE OF A C-60 FULLERENE...........................................................................................8 FIGURE 4. COMPUTER IMAGES OF VARIOUS FORMS OF CARBON NANOTUBES. ....................................................8 FIGURE 5. “FOREST” OF ALIGNED CARBON NANOTUBES.......................................................................................8 FIGURE 6. ZINC OXIDE NANOSTRUCTURE SYNTHESIZED BY A VAPOR-SOLID PROCESS........................................9 FIGURE 7. COMPUTER IMAGE OF AGALLIUM ARSENIDE QUANTUM DOT OF 465 ATOMS.....................................9 FIGURE 8. COMPUTER IMAGE OF GENERATIONS OF A DENDRIMER......................................................................9 FIGURE 9. COMPUTER IMAGE OF A NANO-BIO COMPOSITE. ...............................................................................10 FIGURE 10. PROJECTED STAGES OF NANOTECHNOLOGY DEVELOPMENT..........................................................13 FIGURE 11. FEDERAL SOURCES TO INFORM EPA’S NANOTECHNOLOGY ACTIVITIES.......................................15 FIGURE 12. NNI NSET SUBCOMMITTEE STRUCTURE..........................................................................................16 FIGURE 13. NANOSCALE ZERO-VALENT IRON ENCAPSULATED IN AN EMULSION DROPLET................................22 FIGURE 14. PIEZORESISTIVE CANTILEVER SENSOR..............................................................................................24 FIGURE 15. EPA’S RISK ASSESSMENT APPROACH...............................................................................................29 FIGURE 16. LIFE CYCLE PERSPECTIVE TO RISK ASSESSMENT ...........................................................................30 FIGURE 17. TRANSMISSION ELECTRON MICROSCOPE (TEM) IMAGE OF AEROSOL-GENERATED TIO2 NANOPARTICLES.....................................................................................................................................................32 FIGURE 18. ZINC OXIDE NANOSTRUCTURES SYNTHESIZED BY A VAPOR-SOLID PROCESS...................................35 FIGURE 19. SEM OF A SCANNING GATE PROBE.....................................................................................................42 FIGURE 20. PARTICLE TOXICOLOGY CITATIONS..................................................................................................53 FIGURE 21. FLUORESCENT NANOPARTICLES IN WATER FLEA (DAPHNIA MAGNA)..............................................60 FIGURE 22. EPA OFFICE ROLES ...........................................................................................................................64 Table of Tables TABLE 1.EXAMPLES OF PRODUCTS THAT USE NANOTECHNOLOGY AND NANOMATERIALS ............................11 TABLE 2. OUTCOMES FOR SUSTAINABLE USE OF MAJOR RESOURCES AND RESOURCE SYSTEMS ...................25 TABLE 3. POTENTIAL U.S. ENERGY SAVINGS FROM EIGHT NANOTECHNOLOGY APPLICATIONS ....................26 TABLE 4. POTENTIAL SOURCES OF OCCUPATIONAL EXPOSURE FOR VARIOUS SYNTHESIS METHODS............44 TABLE 5. EXAMPLES OF POTENTIAL SOURCES OF GENERAL POPULATION AND / OR CONSUMER EXPOSURE FOR SEVERAL PRODUCT TYPES...................................................................................................................................45 TABLE 6. SUMMARY OF WORKGROUP RECOMMENDATIONS REGARDING NANOMATERIALS...........................92 viii EPA Nanotechnology White Paper FOREWORD Nanotechnology presents opportunities to create new and better products. It also has the potential to improve assessment, management, and prevention of environmental risks. However, there are unanswered questions about the impacts of nanomaterials and nanoproducts on human health and the environment. In December 2004, EPA’s Science Policy Council (SPC) formed a cross-Agency Nanotechnology Workgroup to develop a white paper examining potential environmental applications and implications of nanotechnology. This document describes the issues that EPA should consider to ensure that society benefits from advances in environmental protection that nanotechnology may offer, and to understand and address any potential risks from environmental exposure to nanomaterials. Nanotechnology will have an impact across EPA. Agency managers and staff are working together to develop an approach to nanotechnology that is forward thinking and informs the risk assessment and risk management activities in our program and regional offices. This document is intended to support that cross-Agency effort. We would like to acknowledge and thank the Nanotechnology Workgroup subgroup co­ chairs and members and for their work in developing this document. We would especially like to acknowledge the Workgroup co-chairs Jim Willis and Jeff Morris for leading the workgroup and document development. We also thank SPC staff task lead Kathryn Gallagher, as well as Jim Alwood, Dennis Utterback, and Jeremiah Duncan for their efforts in assembling and refining the document. It is with pleasure that we provide the EPA Nanotechnology White Paper to promote the use of this new, exciting technology in a manner that protects human health and the environment. William H. Benson Charles M. Auer Acting Chief Scientist Director, Office of Pollution Office of the Science Advisor Prevention and Toxics