Green Nanotechnology: Straddling Promise and Uncertainty

Barbara P. Karn and Lynn L. Bergeson

anotechnology has been called the second Indus- Electrical properties also can change at the nanoscale. The trial Revolution. Its seemingly limitless potential rolled-up carbon chicken-wire structure of carbon nanotubes will continue to inspire innovations in a dizzying (CNT) is a conductor when the chicken wire falls in a straight array of beneficial applications and briskly trans- line. The nanotube is a semiconductor if the chicken wire is formN society. Despite the hope and promise nanotechnology slightly twisted. Semiconductors form the basis of the micro- brings, engineered nanoparticles, the tiny engines driving this processor chips and transistors in our computers and commu- new transformative technology, also generate a palpable appre- nication devices. The giant magnetoresistance effect occurs hension due to their largely unknown implications on human at the nanoscale and enables computer hard drive storage and health and the environment. Enter green nanotechnology, an cell phone memory. Its inventors, Peter Grünberg and Albert approach to managing the potential environmental, health, Fert, won the Nobel Prize in Physics in 2007. and safety (EHS) risks associated with the manufacture and Because of the special properties of materials at the use of nano-enabled products while fostering their responsible nanoscale, nanotechnology has permeated all sectors of our development and application. economy. Semiconductor technologies, memory and storage This article describes green nanotechnology and discusses the technologies, display technologies, optic/photonic tech- reasons why traditional chemicals-assessment and management nologies, energy technologies, bio/health technologies, and approaches may not be adequate in all cases in the near term consumer products such as textiles and cosmetics all make use when applied to nanomaterials. It outlines the reasons why green of nanoscale materials. nanotechnology may serve as an alternative approach to chemi- Government and marketing sources predict a $3 trillion cals assessment when applied to nanomaterials and suggests some market for nanotechnology-related products by 2014. Is there measures to advance the goals of green nanotechnology. a chance that this huge industry will be green and sustainable? Nanotechnology encompasses the science of nanomateri- What, after all, is “green” when applied to nanomaterials and als, forms of matter in a particular size range, roughly between their making? 1 and 100 nanometers (nm). Nanomaterials are bigger than most molecules and smaller than bacteria cells. They can con- sist of groups of single elements such as metals, groups of com- Green Nanotechnology pounds such as metal oxides, tubes or wires of elements, soccer There are two key aspects to green nanotechnology. The ball structures, branching structures, and infinite combinations first involves nano products that provide solutions to envi- of these. Nanomaterials can be regular and geometric like ronmental challenges. These green nano products are used crystals or irregular like foam. to prevent harm from known pollutants and are incorporated While nanomaterials are intentionally designed to be into environmental technologies to remediate hazardous waste unique, what is common to all is their super small size, which sites, clean up polluted streams, and desalinate water, among imparts properties that are surprising and special. For example, other applications. Nanomaterials enable clean drinking water gold is gold when we wear it or spend it. A 25 nm nano-sized through membrane technologies or nano-based procedures clump of gold atoms is red; a 50 nm clump of gold atoms is that destroy pathogens and toxic chemicals. Green nano prod- green. The optical properties, i.e., color, change merely be- ucts also enable sophisticated sensing and monitoring devices cause of the size. The gold we wear is not active. At the nano- to detect hazardous pollutants, plant pathogens, and related scale, gold becomes an active catalyst, helping turn chemicals toxins. X and Y into product Z. Nano products also further sustainability. New forms of energy generation, such as fuel cells, thermoelectric devices, Dr. Karn is a scientist with the U.S. Environmental Protection Agency’s solar cells, and improved batteries, reflect the application of Office of Research and Development in Washington, D.C. Ms. Bergeson nanoscale materials. Green nanotechnology miniaturizing is managing director of Bergeson & Campbell, P.C., in Washington, products, which uses less material, are lighter to transport, and D.C., and president of The Acta Group, L.L.C. and The Acta Group thereby save energy and fuel. EU, Ltd with offices in Washington, D.C., and Manchester, UK. They The second aspect of green nanotechnology involves may be reached at [email protected] and [email protected]. producing nanomaterials and products containing nanomate-

Key Nano Uncertainties A corollary principle that is very much a part of green nan- The world’s fascination with the science of the teeny- otechnology is waste prevention. Because many nanomaterials tiny is tempered by a disconcerting fear of the uncertainties are or will be made by self-assembly or solid-state processes, surrounding nanomaterials. The image conjured up in Eric there are fewer opportunities to generate waste resulting from Drexler’s groundbreaking book Engines of Creation: The Com- chemicals trying to find each other in the reaction “soup.” ing Era of Nanotechnology (Anchor 1986) of “unruly herds” of Green engineering principles are also applicable as nano- atoms gone awry is not the source of the concern as much as materials increasingly are incorporated into larger, more con- the fear of the unknown. In this case, the unknown is the lack ventionally scaled products. Green engineering “embraces the of knowledge in key areas regarding the human health and concept that decisions to protect human health and the envi- environmental implications of nanoparticles. Complete data ronment can have the greatest impact and cost effectiveness sets for the most commercially common nanoscale materials— when applied early to the design and development phase of a CNTs, metal oxides, carbon fullerenes, and related materials— process or product.” U.S. Environmental Protection Agency do not yet exist. The recent data that have emerged are, in (EPA), Other Sustainability Resources, Green Engineering, some instances, troubling. For example, research indicates that http://epa.gov/ncer/p3/other/index.html (last updated June 16, multiwalled CNTs can penetrate the lining of the lung. These 2009). The most relevant timeframe in the green-engineering data supplement earlier studies that show multiwalled CNTs life cycle of a nanomaterial is the early stages of the technol- injected into the lining of the abdominal cavity of mice cause ogy, the design stage. Green engineering requires that we inflammation and granulomas suggestive of the onset of meso- consider the full life cycle of a product, from the extraction of thelioma of the abdominal lining, a reaction similar to that of the materials from the ground through manufacturing, product other durable fibers, including asbestos. use, and its end of life. Green nanotechnology’s focus on the Scientific uncertainty, however, should not dampen our full life cycle can help us better prepare for recycling, reuse, collective drive to innovate. Rather, any such uncertainty or remanufacture of nanomaterials and nano-enabled prod- should be properly reflected in governance and regulatory ucts, thus minimizing the generation of new hazards through policies that protect human health and the environment and unplanned disposal. recognize the fragility of this evolving technology as it matures Nanomaterials can be engineered to be greener, thus commercially. At the core of this uncertainty is the fact that minimizing potential risks through product design and the use nanoparticles and nanomaterials are unique, and their highly of safer materials. For example, nanomaterials can be coated variable physical-chemical nature contributes significantly

Published in ,Natural Resources & Environment Volume 24, Number 2, Fall 2009. © 2009 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association. not only to the commercial value of the nanoparticles but also whole, current laws are adequate and that no news laws are to their hazard profile. As a result, grouping nanomaterials to needed. While the government’s statutory authorities may be assess efficiently their hazard characteristics, as is currently sufficiently broad to address nano, the government’s expertise, done with larger-scale chemicals, and extrapolating from data resources, or political will may not be sufficient to deploy these pertinent to a nanoscale substance’s larger, conventionally legal authorities in a way that will manage nanotechnology sized counterpart is not currently possible due to the size dif- risks effectively in the near future. ferences and the inherently different nature of materials where There is no oversight mechanism currently in place to quantum interactions take place. rationalize disparate policy and regulatory initiatives underway Additionally, conventional analytical tools and protocols throughout the federal government. This fact inspired one may not accurately capture the hazard potential of nanoscale prolific author, Dr. J. Clarence Davies, to call for the creation materials. Standard chemical analytical and monitoring tools of the Department of Environment and Consumer Protection. and detection equipment are not typically calibrated or engi- In his 2009 report Oversight of Next Generation Nanotechnol- neered to apply readily or at all to nanoscale materials. Even ogy (www.nanotechproject.org/publications/archive/pen18/), if such tools were readily available, there is little consensus on Davies notes that this new agency would foster more inte- how to test nanomaterials and which materials to test first. To grated approaches to governance and use “sustainability plans” the extent there is broad agreement among nano stakeholders, developed by product manufacturers to summarize known it is rooted in the belief that much more EHS testing needs to information about the product’s components, its adverse ef- be done to identify, characterize, and manage potential risks fects, a product life-cycle analysis, and an explanation of why effectively to ensure that the commercialization of nanotech- the product would not cause any undue risk. nology occurs responsibly and sustainably. To some, the lack of broad federal integration has ham- In this regard, there are many nano EHS data develop- pered effective regulatory oversight initiatives across agencies. ment initiatives underway globally, too numerous to summa- Within EPA, regulatory programs implementing the core rize here. While each is essential, taken as a whole they are environmental laws likely need revision to address emerging unlikely to address any time soon the large need for additional technologies like nanotechnology. Many federal environmen- EHS data. One recent estimate for U.S. costs alone for toxic- tal laws that address chemicals, and their implementing pro- ity testing of existing nanoparticles ranges from $249 million grams, offer volume-based exemptions of one form or another. for optimistic assumptions about nanoparticle hazards (that For example, the Toxic Substances Control Act (TSCA) the nanoparticles are relatively safe and require only screening low-volume exemption from notification for chemical produc- assays) to $1.8 billion for more extensive, long-term in vivo tion is limited to less than 10,000 kilograms per year. Resource testing. Conservation and Recovery Act small-quantity generator and the Clean Air Act standards are mass-based. For the small production amounts of most nanomaterials, volume/mass-based Emerging Regulatory/Governance exemptions make little sense, excluding nanomaterials from Frameworks our current regulatory system premised on a metric that simply The paucity of toxicological and ecological effects data and does not apply. information on engineered nanoparticles and nanomaterials EPA’s Office of Pollution Prevention and Toxics (OPPT) has challenged the ability of regulatory agencies to provide is farthest along in developing a body of work under TSCA effective oversight of nanotechnology’s development and com- pertinent to nanoscale materials. Because TSCA is the mercialization. Over the past several years, governmental bod- principal federal law that authorizes EPA to regulate chemi- ies and nano stakeholders alike have initiated a broad range cal substances, EPA has focused extensively on deploying its of actions intended to manage nanotechnology prudently TSCA authority to regulate nanoscale substances, materials and communicate as much to nano detractors. The activities that are characterized as TSCA “chemical substances.” On the include a diverse mix of regulatory initiatives, government- regulatory front, EPA has prepared a policy statement dated initiated voluntary/mandatory data-gathering initiatives, and January 2008, TSCA Inventory Status of Nanoscale Substanc- various private-sector product stewardship/codes of conduct es—General Approach, to assist manufacturers in determining initiatives. whether TSCA Inventory requirements apply to nanoscale A fundamental issue that has been debated for years is chemical substances. EPA has received and reviewed several whether the range of existing legal authorities and gover- new chemical notices under TSCA Section 5 for nanoscale nance tools are adequate to address the potential risks posed materials, including CNTs. On October 31, 2008, EPA pub- by nanotechnology. The American Bar Association Section lished a notice outlining the TSCA requirements potentially of Environment, Energy, and Resources Nanotechnology applicable to CNTs and advised CNT manufacturers of EPA’s Papers (www.abanet.org/environ/nanotech) early and com- position that CNTs must be listed on the TSCA Inventory. prehensively provided much-needed legal analyses of the core On November 5, 2008, EPA issued a final significant new use environmental statutes and the authority each conveys to EPA rule (SNUR) for fifty-six substances, two of which included in mitigating and preventing potential nanotechnology risks. nanoscale substances. After March 1, 2009, CNTs that are Although the debate continues, many believe that, on the manufactured for commercial purposes and that are not listed

Published in ,Natural Resources & Environment Volume 24, Number 2, Fall 2009. © 2009 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association. on the TSCA Inventory or otherwise exempt could be subject a proposal to require businesses to report nanoparticles being to compliance monitoring. used, provide available toxicological information, and outline These focused EPA OPPT efforts are laudable. They do not, measures for safe handling of the materials. A similar measure however, reflect a systematic, comprehensive, or concerted was considered in Cambridge, Massachusetts, but ultimately effort within the federal government to make domestic envi- failed. More recently, in January 2009, the California Depart- ronmental regulatory programs nano-ready. Nanotechnology ment of Toxic Substances Control (DTSC) announced that research, development, and policy activities are coordinated it is requiring the submission of data “regarding analytical test through the twenty-five federal agencies and departments of methods, fate and transport in the environment, and other rel- the National Nanotechnology Initiative (NNI). Each of these evant information from manufacturers of carbon nanotubes.” entities, however, has separate regulatory and governance DTSC states that the term “manufacturers” includes persons frameworks for addressing nanotechnology pursuant to the le- and businesses that produce CNTs in California or import gal authorities granted to each under various enabling statutes. CNTs into California for sale. The level of effort among federal entities on nano-specific initiatives regarding governance is disparate. For example, within EPA, OPPT and the Office of Pesticide Programs are much Private-Sector Governance Strategies further along than EPA’s air, water, and waste offices. Other Based on the perception that traditional governance agencies such as the Consumer Product Safety Commission mechanisms, including statutory measures and notice-and- appear to be at relatively early stages of nano-development, comment rulemakings, are ill-suited tools for nanotechnology while others such as the National Institute for Occupational governance, the private sector, in concert with governmen- Safety and Health are quite expert in areas involving nano tal entities in some instances, is pursuing an unprecedented workplace practices and controls. number of innovative governance initiatives to address nano- Governmental bodies have, not surprisingly, responded technology. These initiatives, which are global in nature, fall differently to the key challenge they each face in regulating loosely into two broad categories: (1) EHS research, nomen- nanoscale materials, the paucity of information on nanoscale clature/terminology, and standard-setting initiatives, and (2) materials. The absence of information on nanotechnology product-stewardship measures. hazard and exposure has frustrated the government’s ability to EHS research, nomenclature and terminology, and stan- provide meaningful oversight of these materials and the manu- dard-setting measures are underway globally at a frantic pace. facturing operations that generate and/or process them. No effort is made here to discuss each with precision in detail. To obtain such information, governments have solicited The work has been undertaken by a wide range of govern- information either on a voluntary or mandatory basis. The ment organizations; international organizations, including the UK Department for Environment, Food, and Rural Affairs International Organization for Standardization (ISO), ASTM (DEFRA) initiated a voluntary nanoscale materials reporting International, and the Organization for Economic Coopera- program in 2006. Under it, DEFRA sought basic information tion and Development (OECD); public-interest/research on nanoscale materials, toxicological and eco-toxicological organizations, including Environmental Defense Fund, Merid- information, and information on risk-management practices. ian Institute, Consumers Union, and ETC; and private-sector By most accounts, the program was unsuccessful. entities, including DuPont, the American Chemistry Council EPA launched a voluntary Nanoscale Materials Steward- Nanotechnology Panel, the NanoBusiness Alliance, and the ship Program (NMSP) in January 2008. Under the NMSP’s Business and Industry Advisory Committee. “Basic Program,” participants were invited to voluntarily OECD, in particular, has been extremely energetic in report available information on the engineered nanoscale the area of nanotechnology. Two OECD Committees are materials they manufacture, import, process, or use. Under the relevant: (1) the Chemicals Committee and its Working “In-Depth Program,” participants were asked to voluntarily Party on Manufactured Nanomaterials (WPMN) and (2) the develop data over a longer period of time, alone or in consor- Committee on Science and Technological Policy’s Working tia, for a particular nanomaterial. Both program components Party on Nanotechnology (WPN), which focuses on creating have garnered little participation from manufacturers and supportive frameworks for innovation on nanotechnologies. other nano stakeholders. Both committees are active, but the Chemicals Committee’s In contrast to the voluntary reporting programs launched WPMN has been particularly busy. by EPA and DEFRA, Environment Canada reportedly intends The WPMN is engaged in work on eight projects, each to launch a mandatory reporting/data-gathering program managed by a Steering Group (SG). The projects are: SG1 in 2009 under Section 71 of the Canadian Environmental “Development of an OECD Database on EHS Research”; Protection Act, 1999. Other countries, such as Australia and SG2 “EHS Research Strategies on Manufactured Nanoma- Germany, are developing data call-ins for nanomaterials. terials”; SG3 “Safety Testing of Representative Set of Manu- In addition, several domestic local authorities have used or factured Nanomaterials”; SG4 “Manufactured Nanomateri- have attempted to use existing legal authorities to compel the als and Test Guidelines”; SG5 “Cooperation on Voluntary submission of information pertinent to nanoscale materials. Schemes and Regulatory Programmes”; SG6 “Cooperation on Late in 2006, the Berkeley, California, City Council approved Risk Assessment and Exposure Assessment”; SG7 “Alterna-

Published in ,Natural Resources & Environment Volume 24, Number 2, Fall 2009. © 2009 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association. tive Test Methods”; and SG8 “Exposure Measurement and why the design of nanomaterials according to the principles Mitigation.” These projects have commanded the interna- of green nanotechnology would complement and support tional cooperation of an unprecedented number of OECD current regulatory and other governance measures intended participants and others and are advancing the goals of each to address risk while fostering the sustainable development of SG at a rapid pace. The output is expected to be historic at nanotechnology. several levels, not the least of which is the international cooperation exhibited to complete the six projects. Much more could be written about these OECD projects. The point is Steps to Facilitate Green Nanotechnology these activities reflect an internationalization of effort focused Emerging governance strategies and mechanisms such on advancing the responsible development of nanotechnol- as those described above demonstrate a concerted effort to ogy that has commanded the time, attention, and commit- ensure effective oversight mechanisms are in place to foster ment of global stakeholders unlike any other transnational the responsible development of nanotechnology. Many of challenge. the EHS concerns associated with nanotechnology could be Other global initiatives are underway in the standard- addressed through more extensive application of green nano- setting arena. The ISO Technical Committee 229 on Nano- technology practices. By ensuring nanoscale materials are technologies created three working groups: terminology engineered with human health and the environment in mind, and nomenclature, measurement and characterization, and their deployment in applications to further sustainability are health, safety, and environment. ASTM International Com- unlikely to invite the kinds of EHS concerns that have been mittee E56 on nanomaterials is also working on nanotech- the subject of much discussion over the past several years. To nology standards, and its Subcommittee E56.01 approved a foster the development of green nanotechnology, stakeholders standard on nanotechnology terminology, E2456-06, in 2007. should consider undertaking the following steps: Importantly, green nanotechnology may be promoted through a new WPMN project on the environmental benefits of nanotechnology, which will convene at a conference on “Potential The absence of information Environmental Benefits of Nanotechnology: Fostering Safe, Innovation-led Growth.” on nanotechnology hazard and Nanotechnology has inspired unprecedented collabo- ration on the development of best-practice standards. In 2007, Environmental Defense Fund and DuPont formally exposure has frustrated the announced the release of their joint effort, the Nano Risk Framework. The Framework is rapidly becoming the standard government’s ability to provide for measuring best-management practice in the nano industry. The Framework defines “a systematic and disciplined process meaningful oversight of these for identifying, managing, and reducing potential environmental, health, and safety risks of engineered nanomaterials across all stages of a product’s ‘lifecycle’—its full life from materials and their manufacture. initial sourcing through manufacture, use, disposal or recycling, and ultimate fate.” http://nanoriskframework.com/page. cfm?tagID=1095. The Framework consists of six distinct steps Develop a Life-Cycle Assessment Appropriate for Green Nano and is intended to be used iteratively as stages of development Products—Before a nano product or production process can be advance and new information becomes available. considered green, its EHS implications must be assessed using Another key initiative is the Responsible NanoCode. an appropriately tailored life-cycle assessment that is capable Britain’s Royal Society, the Nanotechnology Industries of identifying and quantifying nanotechnology EHS implica- Association, Insight Investment, and the U.K. government- tions and gauging the trade-offs that arise in the context of sponsored Nanotechnology Knowledge Transfer Network their applications. For example, life-cycle assessment could collaborated on the proposed code. The objective of this compare the energy savings brought about by a nano-enabled “principles-based” voluntary code of conduct is to encourage product with the same product’s larger-scaled counterpart. industries, retailers, universities, research institutes, and other Establish Performance and Branding Standards for Green public or privately funded bodies involved in developing, Nanotechnology—Too little is known about green nanotech- manufacturing, and selling products of nanotechnology to nology, and the term itself is not well understood. Stake- adhere to seven principles to demonstrate responsible gover- holders should consider establishing specific standards that nance. Code proponents launched a consultation period in products would need to meet to be considered green. If these the United States, and in May of 2008, the Working Group standards are met, stakeholders should use the criteria in of the Responsible Nano Code signed off on the code. branding products as “green nano.” This brief discussion does not address directly green Provide Tax and Related Business Incentives to Innovators to nanotechnology principles. It does, however, help explain Encourage Application of Green Nanotechnology—Among