United States Government Accountability Office
GAO Report to the Chairman, Committee on
Trang 2BGA Oe GAO Highlights ean f 400.0 wpa,
Why GAO Did This Study Nanotechnology involves the sito control muti a te acl ‘ta nanometer—onebilionth ofa meter The work market for
anomeric expected to rach etalon by 2016 In thls context, GAO (1) ented examples of urn’ and potential ss of hahoelelals C) deevaied Tumor health and environmental Fis rom nanomaterials (3)
Totter understarl andrea the Hiss posed by nanomaterials as
G) identified approaches that other
Select nahn authorities and
‘ures the potential sks
‘Suctated wh nanomaterials, CAO smagzelelected aws ml eulations, reviewed information (on EPA's Nenoocae Materials Stewardship Progeam, and sameludl with PPN sa ni legal experts perspectives on EPA authorities to obtain he
{o regulate nanomaterials, Cen (GAO recommen that EPA complete planet mo itx Feulatory flamework for ‘anomafedal te ead EPA soncamel wgh mạc
recommendations and provided, ‘eetndea coon, whieh Wwe
LS NANOTECHNOLOGY
Nanomaterials Are Widely Used in Commerce, but EPA Faces Challenges in Regulating Risk
What GAO Found
‘Companies around the world are currently harnessing the properties of aBoinaterlsTör use in products across a number of setors and are ‘expected to continue to fn new uses for these material GAO identified a ‘aroty of products that currently incorporate nanomaterials already avaiable In commerce across the following eight sectors automotive; defense and acrospace: electrons and computers; energy and environment: food and grieultre; housing and construction: meieal and pharmaceutical at personal care, cosmetics and other consumer prodcts, Within ench of these Sectors, GAO also identified a wide varety of ether uses that are currently Under development and are expected tobe asllable in Ihe flare
‘Tho extont to which nanomatorials presenta isk to human health and the environment depends on a combination of the toxley of specie ‘hanomaterals ad the route ad level of exposure to these materials
[thou the body of research rele to nanomaterials growing, the current ‘understanding ofthe iss posed by these materials is uted This is because the manner In which some studles have been conducted does not allow for ‘all comparisons with newer studies or Beatie there hes been a greater focas.on certain nanomaterials and not thers, Moreover he abit to conduct necessary research on the toxlclty and risks of naomaterials may be farther hampered bythe lack of tols to conduct such stiles and the lack of rmorlls to predict the characteristics of manomalriai
EPA has undertaken a mulipronged approach o understanding and regulating the iss of nanomaterials, ineluing conducting research and Jmplementng a voluntary data collet program Furthermore, under its existing statntory framework, EDA has regulated some nanomaterials bit not thers Although EDA is planning to tsue adil regulations tater his {Year these changes have nol yet gone into effect and products maybe "tering the market without EPA review of all valabe information on their potential risk Moreover, EPA faces challenges in eloctively regulating "hananiaagils that ay be telessed nal, water and waste becatse tacks {he technology lo monitor and characters these materia the salutes include volume based regulatory thresholds that may'be too high for
effectively regulating the production and dsposal of manomatenias,
Lie the United States, Australia, Cana, the United Kinglom, mndthe European Union have begun collecting dats to understand the potential sks ssaoclated with nanomaterials and are reviewing ther legslaive authontes {o determine the need for munications Austral andthe United Kinglom Ihave undertaken a voluntary data collection approach whereas Canada plans terequre companies to submit certain types of information Some US states, like California, have also begun to ales the potential sk fom
‘nanomaterials, for example, collecting information from manufacturers on ‘limited namer of manomateriss in se in those sates and making some of this information publily avilable
Trang 3Contents Letter 1
Background Nanomaterials Currently Enhance Products across a Number of 5 Industry Sectors and New Uses Continue to Be Developed 8 Potential Risks to Human Health andthe Environment fom ‘Nanomaterials Depend on Tosieity and Bxposure, and Gurcent
Understanding of the Risks Is Limited mã [BPA Has Taken a Mutipronged Approach to Managing the Potential Risks of Nanomaterials but Faces Varlous Challenges
in Regulating These Materials a (Other National Authorities Are Collecting information on ‘Nanomaterials and Are Evaluating Their Legislation to Ascertin
i Changes Are Needed “ Some State and Local Governanents Have Begun to Address the Risks of Nanomaterials it Conclusions Recommendations for Executive Action mm 0 Agency Comments a ‘Appendix T Objectives, Scope, and Methodology @ ‘Appendix I ‘Comments from the Environmental Protection Agency 35 ‘Appendix IT GAO Contact and Staff Acknowledgments mm Related GAO Reports mm Figures
Figure 1: Examples of Nanomaterials as Raw Matera, Inermediates, and Finished Products 8
igure 9: Bxamples of Current and Potential Nanotechnology Imovations that May Be Used in an Automobile
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Figure & Examples of Current and Potential Nanotechnology
Inmovations That May Be Used in a Mobile Phone “ Figure + Examples of Current and Potential Nanotechnology Innovations That May Be Used in a Drink Bottle 18 Figure 5: Examples of Current and Potential Nanotechnology Inmovations That May Be Used na House 20 Figure 6: Potential Exposure Routes throughout the Life Cycle of ‘Nanomaterials 28 igame 7: The Increase in Environment and Hluman Sefety Research Relating 1 Nanomaterials since 2005 mm
‘Abbreviations
cERCLA Comprehensive Environmental Response, Compensation, and Liability Act EPA, Environmental Protection Agency
FIFRA, 180 Federal Insecticide, Fungieide, and Rodenticide Act Incernational Organization for Standardization NICNAS Assessment Scheme National Industrial Chemicals Notification and
NẠI National Nanotechnology Initiative
8D Organisation for Economie Co-operation and Development RCRA, 'Resonree Conscralion and Reeotery Aet
REACH Regulation, Bvaluation and Authorization of Chemicals SNUR Signiticant New Use Rule
TSCA w ‘Toxie Substances Control Act of 076 ¬
Wilson Center Woodrow Wilson International Center for Scholars Project on Emerging Nanotechnologies “Thais a wok of he US, gover ard inal uj o capri prlacson ne United Sates The publchad preauct may be eproauced ard aeutes ne sre ‘not ume pemeson fe GAG However oauee ne wort ay cota ‘Spygned msger or aher malar peices om the Soph alr may be receosry you wh opoduce hie mato separte
Trang 5i & GAO Taited States Government Accountability Offce Washington, DC 20548 May’ 25, 2010 "The Honorable Barbara Boxer Chairman
Committee on Environment and Public Works Unived States Senate Dear Madam Chairs
"The rem “nanotechnology” encompasses a wide range of innovations ‘nage on the understanding snd control of matter atthe scale of
nanometers—the equivalent of one-illionth of a meter For ilustration, a sect of paper is about 100,000 nanometers thick, s human bat is about 50,000 nanometers wide, and three gold stom lying side by side aze about Tanometer long, Unnsual properties ean emerge in materials ranfaetured athe nanoseale- including calle, electrical, magnet sechanical, optical, and thermal properties—that differ in important wayss Irom the properties of conventionally sealed materials Some ofthese new properties ean enhance products and thet appleatons across a number DoF sectors, ineluding electronics, medicine, an defense The world maeket for nanoieehnology-rlated products is growing an is expected to total 'etoeer ST ilion and $36 teilion hy 2015
Nanomaterials can oceur naturals be created inckentally, abe
manufactured incetionals, For example, naturally oceurting nanomaterials ‘can be fount in soleanie ash, forest fre stoke, an ecean spray Incidental ‘nanomaterials are by-products of iustrial processes sul a ining ad metal working and combustion engines, sh as those used in ears trucks, And some tains In contrast, nanafactared nanomaterals(sometines ‘aled exgincered nanomaterials) particular fanetion or property, such as improved strength, decreased have been specifically desigred fora
‘Weight of increased electrical conducts Our review wil oes on manufactured nanomaterials, rater tha nano-sized materials tht occur naturally the ensironnient or are Incidentally peodiced, and far the renter ofthis report, we sil ell such materials “manufactred ‘nanomaterials or simply "nanomaterials" While the use of nanomaterials, Told promise forthe future, heir small size and unin properties raise ‘Geccia avout garcia aie’ oeuple Urine eerioiiene hat Pa result fom expose to them during their ranufacture, ve, tvlđi<poSg1
Risk is usually defined as the potential forharmul effets co uman healt ‘or the enviroament resuling from exposure toa substanee—in this ease, ‘anomaterias In general tems, sk depends on a combinstion ofthe
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‘exposures person or the environment has Inerent roxtity ofthe ehemiea i other words, the same exposure (0 N80 a he substance as well asthe ‘hiferen: substances each with their on toxieny would rel in diferent Jevels of potential risk
‘The Environmental Protection Ageney (EPA) administers several laws that regulate chemicals pesticites, pollutants in air or wate, and wastes that, nay be composed of ar contain nanomaterials, ‘hese laws include the following
‘the Toxle Substances Control Act of 1978 (TSCA), which authorizes EPA, {o require chemical companies to report certain information abont
‘chemicals used in commerce and authorizes EPA to requte testing oF and ‘control chemicals that pose an unreasonable risk to human health oF the fensroainent, sinong other things,
‘the Federal insecticide, Fungicde, and Rodenticde Act (FIFI), whieh authorizes EPA to regulate te sale and use of pesticides and prohibits tuarketing of pesticides that have not been registered ith EPA the Clean Air Act, which requires BPA tose standards for common ar pollurants and to regulate dust sontees of hazardous it polltsats the Clean Water Act, which authorizes BPA (o regulate discharges oF pollutants into federally regulated waters
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‘he Comprehensive Fuviconmental Response, Compensation, and Liability set (CERCLA), commonly keown as Superfund, which authorizes BPA to ‘compe parties resporsible for contaninatingsiesto clean them up oF to ‘conduct cleanups self and thea seek reimbursement from responsible parties
(On the international level, other national muthoriies are also concemed hot the potential risks of nanomaterials and whether their curtent "regulatory framework authorities are sufficient to address these sks, For ‘example, Australia, Cenada, the United Kingdom, an the Buropean Union Ihave begun to review their regulstary approaches for nanomaterials, Furthermore, the Ozganisation for Economie Co-operation and Developivent—a form in which the governments ofa developed
‘couintces, including the United States, work together to address economic Social, and envicontventalissves has established a "working party” on ‘nanomaterials In addition tothe international focus on this opie, some US states have begun to explore ways to addzess the potential risks of nanomaterials
In this cantex, you asked us to (1) identify examples of eusrent and potential uses of navomaterals, (2) detennine what is known zbout the potential hana healt and environments sks from nanomaterials, (3) Specifically assess actions EPA has taken Co beter understand and regulate the risks posed hy nanomaterials as wells ite authorities to do 0, and (1) vlentify approaches that selected other national authorities have taken to address the risks assoclated with nanomaterials in addition, you asked us to identify any US slaces and localities that have began 10 ‘aves the sks fron nanomaterials
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‘We also interiewed knowledgeable stakeholders, including officals fom he National Navoteehwology inate, the Wikon Center, the Natal Academy of Sciences, Las Teseareh, and the NanoBusiness Alletee-—a, nanotechinology-related business association We nsed an iterative process, ten referred to as "snowball sampling.” to identify knowledgeable stakeholders and we selected for interviews those who would provide us with a broad range of pespeetives.on the current and potential uses of nanomaterials,
‘To determine wha is lnown about the potential! human health and cetvitonmental risks of mancfactured nanomaterials, we reviewed {documents that had been published by peer-reviewed journals, {government agencies, and international nonprofit organizations In ‘conducting this review, we searched databases, asked knowledgeable stakeholders to idensify relevant studies, and reviewed studies frm article bibliographies to ident sdtional sourees of ưørmailoh on the
potential risks Our review focused on 20 seh Sti, selected in part Dbecause they provided a synthesis of available research related to nanomaterials risks and eovered a variety of nanomaterials For the purposes ofthis report all the documents shidies, and synthesis shdles ‘we reviewed wil be referred fo as “shies” We also spoke with «variety ‘of knowledgeable stakeholders representing industry, academia,
nongovernmental organizations, and the regulatory community, These inowledgenble stakeholders were also selected using a snowball sampling method,
To assess actions EPA has taken to better understand and regulate manufactured anomaterits and its suhorites to do s0, we analyzed selected laws and regulations, ineluding TSCA, FIFRA, the Clean Air Act, ‘the Clean Water Act, RCRA, aad CERCLA, We also reviewed data and reorts on EPA's Nanoscale Materials Stewardship Program, whieh EPA “developed to encourage companies ta voluntarily develop and submit tnformation tothe agency on the eharactersties of nanomaterials Furthermore, we consoited with BPA olfciais and legal experts to obtain ‘heir perspectives on EPA's asallable suthorities co resulate manutaetared nanomaterials
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Background
‘stakeholders who identified them as having aken actions related co better uunderstauding assessing, or regulating the potential risks of nanomaterials To Mlentify any states that way be taking action with regent tovsanomaterials, we spoke with federal egalatory indasty and
‘vironmental groups and other knowledgeable stakeholders, inching ‘the Envizonmental Couneil of States
A more detailed description of our seope and methodology is presented in Aanpendis L We performed our work between May 2000 and May 2000, 30 accordance with generally accepted government auditing standards Those standards require that we plan and perform the aut to obiain suite Anptopriate evidence to provide a reasonable basis fo our findings ad ‘conelsions based on our aut objectives, We believe that the evidence ‘oblained provides a reasonahle basis for our findings and conclasions ‘based on our ait objectives
Te fiscal year 2009, federal support for nanotechnology research totaled about 1-7 billion Carmlatively from fiscal year 2001 through fiscal year 2009, federal agencies have devoted over $10.5 billion to nanotechnology research To gulde federal development of nanctechnology, che National Nanotechnology Initiative (SND was established in 2001 ta suppor long erm research and development iøqed at accelerating the discovery, development, and deployment of nanoscale science, engineering, and {technology The NNLs.a mechanism to coordinate related acusiies ofthe 25 currently pantipating federal agencies that the nanotechnologs fun! nanosealereseareh or have a stake inthe outcome of this research, such as those agencies that may regulate products containing
xnanomaterials While the NNT is designed to facilitate intergovernmental ‘cooperation and ken overarching goals and priorities for ranotechnology research, iis not a research program and hats no Funding ‘or authority to dictate the nanotechnology research agenda for
partiipating agencies orto ensre that adequate resources are avaiable to achieve specific goals Instead, participating agencies develop sind fan their own nanotechnology research agendas In fiscal year 2009, six NNT agencies uecounted for over 95 percent of federal nanotechrology research reported, These are ihe Department of Defense, the Department ff Buergy BPA, the Department of Health and Human Services’ National Institutes of Health, the Department of Commerce's National Institue of Standards an Teehwology, and the Nacional Selence Foundation
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Carbon-based materials These nanomaterials are composed mostly of carbon, and are most commonly spherical, eliptiea, or tabularin shape Speriea and ellipceal carbon shapes are referred to as fllerenes, while “mbular ones ae called aanotubes
Metal-tased materats These nanomaterials include nanoscale gol, nanoscale silver, and metal oxides, such as Gianiun dioxide They nisa ‘nce quantumn dots, which are closely packed semiconductor erytale ‘comprised af nndzeds oe thousands of atoms, on the see ofa few nastometers (oa few hundred nanometers
Domainers These nanomaterials ave nanoscale polymers built fom branched units The surface of a dendrimer has nimerous braach ends, ‘whiel can be tired to pervorm specific ehenteal functions Also, some ‘enalimers contain interior esvities inca which other molecules ean be placed, such as for drug delivery
Composites These materials combine nanoparticles with other
‘nanoparticles or with lirges,conventional-seale materials, Far example, ranopartiles, such as nanoscale clay ean be eombined with other matetals to form a composite maveral
IEPA uses 2 risk assessment proces to estimate the extent of harm, if any, that canbe expected from exposure toa given substance thronghout its life eyele and lo help regulators determine whether the risk meets the ‘requirements for taking setion under is statutory authorities, such as Danning the substanee's production or Hinting its use Te base isk assessment paradigm includes the following:
an evaluation of scientific information on a substanee’s hazardous
properties—or toxiety—w hich may potentially affect human healt or the #lironmeni
‘the dose-response relationship—the eelationship between the extent of| ‘exposure (dase) and the esuting ebanges is health or had fuacHoa (esponse)— deseribos the roxie eet of substance, and ‘exposure —the extent to whieh humane ofthe environment are expected tobe exposed to the chemical
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‘assessment approaches, a materials properties may’ be moaliied or ‘exposure controls incorporated to minlanize and mnanage potential hề [Nanotechnology is an example ofa fast paced technology that poses challenges to agencies’ policy development and foresight efforts We have conducted past work looking at the challenges of exercising foresight when addressing potentially significant but somewhat uncertain tends" including technology-based trends that proceed atx high “lockspeed,” that is, (1) faster pace than trends an agency has dealt with previously oF (©) quantitative rate of change that is either exponential or exhibits a pattem of doubling or tipling within ord years, possibly ona repeated basis" As our prior work has noted, when an agency responsible for ensuring safety faces a set of potentially significant high-clockspeed technology-based trend, it may successfully exercise foresight by carrying fou activites such as
considering what is known shout the safety impact ofthe trend and deciding how to respond 10
reducing uncertainty as needed by developing additional evidence about the safety of the trend and
‘communicating with Congress and others about the trends, agency responses, and poliey implications,
Similarly, our 2tst Century Challenges report raised concern about ‘whether federal agencies are poised to address fast paced technology based challenges.’ Other foresight literature iustrates the potential future ‘consequences of falling hehind a damaging trend that could be countered ‘iron chemist stn own snaanalechemity, ihe sgn of chen pros su procreesthedi etchant ed stmt lo coal pec mig relia ae geeTtion of azar tao
` e e e
“Gno, phew Sty: Foenght Innes Catone DOT rts Asses nd Resa oN Perko tea Tends, G09 (Meshing DOr 9, 8),
Trang 12Nanomaterials Currently Enhance Products across a Number of Industry Sectors, and New Uses Continue to Be Developed
by ealy action These analyses suggest that mnless agencies and Congress ‘ean slay abreast of tehiological changes, sich 2s nanotechnology, thes nay find dhemselves “in a constant eatelvup position and lose ce eapaciey toshape outeomes:
Industries around the world ave harnessing the properies of nanomaterials for a yurety of prolucts across e nutnber of sectors and are ‘expected ro continue Co fn new uses for these materials Nanomaterials ‘can enter the marketplace as materials themselves as intermediates that either hace nanosealefeatizes or Meorporate nanomaterials, da final ‘nano-enabled products (se Ns 1) Far exaaple, a manifaccrer ofc !nznopartcies can provide them to aplastic manufaetarer, who ean use thems to enhance a composite material (an intermediate) The plastic manufacturer can then sel the composite material oan antomabile ‘nnufacter, who cay use the matertal to nol parts for ears (nan: enabled products)
As the uses of nanomaterials continue to eval¥e, the overall are for them is growing along with the degree to whieh they are permeating our
ge aw
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Automotive
‘ecexyday lives [8 2009, the Woodrow Wilson Intemational Center for Scholars’ Project on Emerging Nanotechnologies (Wilson Center)
dented alist of more than 1000 nanovenabled products currently on the market reflecting 1.379 percent inerease since this st was firs compiled in 2008." The list contains information on products from aver 20 countries ‘hat ean be purchased and use hy consumers and provides a baseline for understating the extent to which nanotechnology isbeing Used AS Lhe Wilson Center hus reported, the trend of an inereased number of products and applications featuring nanomaterials i also refleced inthe number of ‘nanotechnology patents issued by the 5 Patent and Trademark Oflce rowing from 125 n 198510495 in 2005, whieh represents a compound annual growth rate of 0 percent The following isa ist of selected Industry sectors and some examples of current and potential uses of nanomaterials within each sector that ilastrate the ubiquitous nature of these materials in commerce Recatse assembling complete catalog of uses wo he dificult in an evaling, dynamic iistry the bats not ‘comprehensive, the examples ehosen are simply lastratve, and we have not verified the eines made by the manufacturers ofthe products used in these examples
rom ear bodies to exterior coatings to engines on the market cola, cars contain numerous enlaneements made possible by nanomaterials Inthe ceurrent marketplace, some bumpers and other auto parts incorporate ‘composite matevais containing nanomaterials, such 2 nanoscale clays, ‘neta, and carbon nanotubes resistant" Many nano-nabled products in the automotive sector involve to make these parts stronger, and mare fre
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promote self-cleaning without altering For example, coatings containing nanoparticles the tanspareney of the costings are currently dispersed in pains and pigments fo make surfaces stronger, smoother, more sera And stain resistant, waterproof, of some combisation ofthese and other properties n adiion, earbon nanotubes offer an especially high tense Strength —the ability to withstand Aout 100 Limes greater than tat of sce! aL one-sinth the weight, and their a stretehing force without breaking —of
‘lectrieal conductivity can be precisely controlled, whieh helps prevent the build-up of static electricity Asa result, when # wanfacturer of fac! Iines adds carbon nanotubes to traditional engineering material, reslts In stronger, safer fuel hes
Inthe future, nanomaterials eould be used to improve the performance of ‘ars, elu reducing wear on engine partsand inereasing battery power and fue efficienes For exaampe,Iobeieants that contzin certain nanomaterials could provide smaler, stronger, and mare stable
alternatives to oflbased lubrleanfs In addition, electrodes clettical ‘condhctors that contain movable electric charges manifactured tthe nanoscale could enable higherperformance rechargeable batteries For ‘example, aecording o documents we reviewed one company that is đet lop[ng a new Ihiin-in battery for eletete vehicles Uses nanoseale metal oxide materials o create crystallized naroparticles that may enable
this nano enabled battery to deliver 20 percent more power, Moreove fel adinives with nanoparticles of cerium oxide could imerease diesel engine hie efficieney.” One Btish company has developed such a plication fora fve-besed ative that, du to the sie-based properties ‘of cerium nanoparticles, ereaes a greater surfuce ares for etalyzing he ‘combustion eactions between diesel and air” According to this company, the result sa cleaner bura that converts more fuel to carbon dioxide,
produces less noxious exhaust, and depasis less carbon on the engine evlner walls an other fel addives: Figure 2 shows examples of some current and potential nanotechnology innovations that may be used in automobiles
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Figure = Examples of Curent eT ears nena ath ptt cry an
Defense and Aerospace ‘manufacturers seeking to take advantage ofthe electrical and mechanical ‘Nanomaterials are beginning to be used in aerospace applications by strength advantages they offer and by the Department of Defense, which is Seeking ways to enhance the (oos available to lis soldiers andthe
effectiveness ofits weapons systems, Nanomaterial polymers are currently being used as sensors that detect very small traces of explosives, which indicate the presence of buried landmines, according to Department “officials Ih addition, according to documents we reviewed, stronger and lighter planes that are better protected against lighting and fre have been made possible by using carbon nanotubes and other nanostructured ‘materials For example, one company has created a nanolaminated
‘material used for planes that is comprised of layers of metal alloys that are stronger, lighter, and more energy absorbent than steel In addition,
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polymers wilh embedded silver nanoparticles Inhuding the interiors ofarerat, tree of microbes.” The palyners contain ae helping co Keep suriaces, nanoscale silver particles that, wien alded 10a products surface, release fons that kill buetora existing on the surface Companies are also Intradcing nanostructured alternatives to standard copper wiring For ‘example, one company has developed a process to ereate highly c0ndlucite sheets of fabri and lengths of yarn containing carbon ‘nanotubes that ean be used to exeate siting td cables for airlines and satellites that weigh much less than truitional eopper wire
Inthe funte, nanomaterlas may help enable the development of new nplestions and prods across wide spetzu ithe defense aren, Including suveilance devices, explosives and propellants, and uniforms For exatuple, areording to Deparment of Defense officials and documents ‘we reviewed nearly “invisible” surveillance may be possible through the ‘ncorparation sd integation of tferent nanotechnologies, ined, aio Teequeney identification chips; integrated eines, ate Diesensors ane “intelligent fabrics, fl, and surfaces Miniaturized survellance techniques under reseaech include using live insects sps" bees) tagged with nanomaterials or tiny winged robots that emalate Insects fo ly ito 2 enemy station to record data Ih addition, more
powerful conventional explosives and faster moving missles may be possible de to the greater amounts af energy provided by nanostrictred ‘laminin fn combination with metal oxides, suchas iron oxide,
‘ngnosemieharedalnzinn allows many more chemical reactions t0 occur Ina given surface area, increasing the explosive force Also, nanomaterials suchas carbon nanotubes embedded in fabric could slow fr liter ‘uniforms and mulifunctional combat suits fr solders The ni could potentially, for example, change color to match the encizonment, become iid eass o protec injuries, or help blaek bullets and
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Electronics and
Computers “Computers and consunvereleetronies have also begun to benefit fon the advantages nanomaterials offer, including proved display sereens and Innpraved eletscal condaetisty, Carbon nantes, quantum dots, and nanoscale layers of polymers ean improve the properties of displays For ‘example, one company has developed an ultrathin, layered system oF polymers tat, nlike conventions! anid crystal dlsplays, requires no backlight or filters, The unagesare Drghter and clearer, and he
technology could make possible full bendable plat displays, according tothe company In addition, since nanomaterials often enhance electrical conductitty, metallic nmopacticies and carbon aanatubes are being used Ina growing mimber of eonduedve coatings, steh as those used for {ouchsereens and solar eel, Aecording co documents We reviewed, one ‘company sells «transparent conductive cating and a costed fn, both Incorporating wanowires, which eonvducseletrety beter than traditional :nsteias The coating and film could eventually replace rare and
‘expensive int tn oxide, currently the most widely used transparent Conductor inthe display industry, Moreover, nanomaterials such 2 lea free, conductive slhesives could eliminate several sees in mannfacring leetronies and could led eventually 10 elimination of some or ll ofthe ‘3000 rans of toxic, leaded solder used every year by the US electronics Industry, seearding fo an EPA document
In he future, computers and electron devices could employ
‘nanomaterials to create more efficient data storage and longer-lasting, rechargeable bateres Memory storage deve enuld become more ‘powerful through a variety of panotechology applications New methods
‘of storing information eleetroseally are emerging fom m variety of applications aimed! at iseeasing the amount of iormation that can be Stored on 2 given plisical spare For example, one company has
‘demonstrated the potential ereate high-density memory desiees with an ‘estiated storage capacity of I terabyte per square ineh—more than 200, tines higher than the storage density of DVD—by storing information ‘mechanically using nanoscale this plastic film * In addition, companies, research institutions, and probes to punch nanoscale indentations into government labs are working to develop nanorhased technology tt cond perfect "microbatteries” which are smaller, eheaper, and more povwerfl than batteries currently in use The greater surface area ofthe nanowires
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Energy and Environment ‘Companies substicte nonrenewable resources with renewable ones, rede polition, ave begining to use nanomaterials fo clean up waste, and inerease the eficency of solar power, Because nanoscale patiles ‘can be more chemically resetive than conventionally sealed particles of the same substance due to their large surface area to volume ratio, these materials ean be useful for environmental remediation Specifically the increased surface area of various types of ceramic or metal nanomaterials “ân result inthe rapid reduetion of contaminant concentrations soi ‘water, ane ras pollutants or toxins in these media react with the nanomaterials Shularly, nanoseale ion i being deployed ina growing ‘number of environmental remediation projeess with results tha are proving suecesstl so fr, according f0 BPA officials Por example, at one remediation projet, researchers injected earbon infused with
;nanopartieles of ron into contaminated soll and found that the ‘nanoparticles made the resulting material more effective at absorbing ‘contaminants nanomaterials than sinilar materials without the nanoparticles In sadn, are being se to create packaging materials made front ‘waste, For example, one company produces nanoparticle paper coatings anade from renewable natural starches that ean replace conventional snaterial in paper coatings, which istypieally made from nonvenewable petroleum Nanonssterials ae also being nsed fo iqprove aomote tatastie converters, which feature nano enabled eaalyss that reduce ae pollution more efficients, One company is manufacturing etal ‘consisting of nanostructures with surface areas much higher than ‘raditional materais ae that allows cataltie converters 0 rem effective under protonged exposure to high temperatures, resulig in tore stable, durable, and cost-effective products, Inthe enengy ares, ‘nano-thabled thin-ty and photovoltaic technologies are making solar power more efficient For example, one company has reported gains in the biy of is thin fi solr cell materials to absorb igh, because the Structure ofthe wanomateral i much stale than the zvelength of Hight, ‘whieh allows to act hke an antenna that concentrates, absorbs, and transfers energy with hgh efficiency,
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“equivalent.” In adaltion, nnotechnotogy-enabled water desalination and ration systems may offer affordable, sealable, aad portable water Heaton in the Future, Filters, comprised of nanoscale pores which incorporate a wide variety of nanomaterials including nanoparticles ‘made of aluminum oxide, ron, and gold an earbon nanotnbes—have the potential to allow water moleeulesto passthrough, but screen out larger molecules, suet as sat fons and other impurities sich 2s bacteria, viruses heavy metal, and onganie material aditon, nanoparticles could be ‘used to improve the efleency of energy transmission by increasing the ‘capacity and durability of insulation for undergeonud electzealeables, allowing cables of smaller diameter to camry the same power as larger ‘ables and to last longer, For example, one company's research shows that ‘able insulation treated with nanacomposites containing nanosiica have about 100 times ionger voltage endurance compared to watreated material In addition, researchers have demonstrated tha carbon nanotube fiber ‘bunds could arty 100 times mare electrical current than the leading {ransmission wives, without as neh energy lass Moreover, one study predicts that f energy transmission losses could be reduced from the ‘current 7 percent asing copper wires fo 6 percent hy using carbon nanotube fibers, che annual enersy savings in the United Seales would be ‘equal 1021 mln bartels of l!
Food and Agriculture "Nanomaterials are currently appearing in Food packaging aud food supplements Specifieals, nanomaterials are being used in food packaging, where applications sul as antimicrobial oanatias thio layers of substanees meant to hamper the grow of bacteria and furgi— are intended to bolster food safety Also, composite materials made of ‘nanoclays embedded in nplon ean offer strong oxygen and carbon dioxide
‘arviers and have been gsed in plastic hotles and fils for packaging, food and beverages Bor example, one company produces a nylon ar cay ‘nanocomposite used as a flexible, puneture-esistant oxygen barrier for ‘beer and carbonated beverage botles in packaging for processed meats and cheeses; and in coatings for paper packaging forulee or dairy products Moreover, products such as ents hoards an food containers Ihave been infused with nanosiver—swhich is known for ts aninerabial
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properties in addilon, encapsulation—the process of using one material {o.deliver nother material side the huma bodys bee in use for deeales bs being improved with nanomaterials, Nanoenearsiited
food products and supplensents can target mitrients, release drugs on & controlled schedule, and mask tastes, For example, some vitamins ean be lificult 10 deliver in beverages beeatse they degrade and may not be easily absorbed by the body, One company has developed nanoscale structures to deliver the vitamin to the digestive spsteny making it exsier for absorption to aceur, Another manfactarer has used nanocepsiles $0 incorporate certain fay acids that have purported health benefits ito dread The company claims he aes in the nanacapaules bypass the taste Dau, emerging only after the nanoeapsules teach the stomach, chs avoiding ary unpleasant taste,
Tn the fature, manufactured nanomaterials could be used to entiance aariculeure; monitor food quality aid feshness: improve the ability to {ack food produets from point of origin to retail sie; and most the ste, exe, and fat content of fod Nenotnaterals are being developed co more efficiently and safely administer pesticies, herbicides, and ferniiers by controlling more precisely when and where they ae released, TR aởdlon, researchers are developing a nanseale powder tat ean Feta Water better dhan other materials an allows Fertilizers to gradually release nnatrients for erops or grass, according tothe Wilson Center n addition, researchers have developed nanobiosensos using nanoseale particles for ‘deeting bacteria, such a salmonella, in water and ad food The ‘work could lead to nanosensors that could be used in Fels co monitor for bacterial contamination of erops, such as spinaeh, lettuce, and tomatoes,
Trang 22‘Figure 4 Examples of Curent ana Potonil Nanotechnology rmovefons Thar lay els Tp eave nn np ati at cry
Housing and Construction ‘Materials and coatings are currently making buildings and homes cleaner and stronger, and in the future wll allow them to operate with higher ‘energy efficiency, according to documents we reviewed, Protective ‘coatings and materials that incorporate nanoparticles of titanium dioxide are being used to manage heat and light by blocking UV ight from the
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‘sun's ways ane ave taking on self-cleaning properties through |
phovoeatalyic effect." For example, ditsniun dioxide is being added to admls, cements, windows, les, and other prodiets fr is sterzing and ‘Seodorizing properties Additionally as Staniam dioxide is exposed to UV lig, i becomes increasingly hydrophilieattracive to water—and is therefore being used for aulifogsing coatings or self-cleaning windows Nanomaterials are also proving beneficial to the constewetion industry by for example, making seel tougher and concrete stronger, more durable and more easily placed, For example, one company has erated a
Structural material with grain size reduced 0 the 200 nanometer scale, ‘whieh icelans haa stength-coesity ratio four Hines that ofthe {oughesttanian alloys and aso resists corrosion Inside the walls of ‘nailing, insltson mace from nanomaterials is proving high thermal performance at mininal weight and thickness, in addition, nanomaterials Are being incorporated into some ait monitoring technologies ai
tien pröducts, ad eneray-ficlent air condoning systems for Fesidentil,eannnercial, and industial settings Fo example, some ait fiters that sre onthe market use nanomaterials ( clean ai eter than ‘conventional materials
In the future, nanoparticle coatings on windows ad bldings could retain ‘energy from the sun fo lve release For example, researchers working ‘on phase change materials—aterials which absorb and release thermal ‘energj—have found that when graphite nanofibers are blended into these materlals the nanofibers prove reaill could be cheaper and more efficient uses of these materials for solar the matera's thermal performance The ‘energy storage In addition, naromaterials may offer approaches that ‘enable materials to “sefsneal” by incorporating, for example,
‘nanocontainers of a repair substance (ean epoxy) throughout the Inatevial When a erack or coreosion reaches a nanocontainer st could be {esigued to open aad release its repair material to il he gap and Sea he crack Figure 5 shows some examples of exrront and potential
nanotechnology innovations thst may be wsed in a hose
Trang 24Favre Bxempes of Curent Not The pte taka el ae imp al ha paren een es BC Medical and
Pharmaceutical Dpecause the extremely stall size of ranomaterials makes possible medical ‘Nanotechnology interventions that ean be directed co individual cell types, allowing for i important to the medical and pharmaceutical industry Detter diagnosis, treatment, and prevention of eancer and other deadly slseases.” Current disease detection efforts include the use of nanoscale
5h Pod and brag Adan geatally pons or veacing he cfety and
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‘sensors to identify biomarkers, such as altered genes, that may provide an arly indicator of cancer Doctors are also ising nanomaterials as markers {wenkiance images from deep inside human tissue, allowing them to tack particles tothe ste of tumor, reslting in earlier detection of tumors CCerizn nanomaterials such as polymer nanopanicls are being use to ‘neat eancer by delivering medieation directly to tumors while sparing "he antimierobial wound! dressings, thereby requiring fewer dressing chante dssne- In addition, silver nanoeestals ae being used in
“and causing patents less pain,
In the future, nanomaterials could be used to help doctors better diagnose “and trea disease In diagnosis, nanomaterials hold promise for showin the presence, location, and contours of cardiovascular and newrolgial sisease, and stall tumors For example, researchers conld use meialle and magnet nanoparticles to enhance imaging the rests of which can be used to gue surgieal procedures and to monitor the effectiveness of nonsurgical therapies in reversing the disease or slowing Its progtession In the fature, sensors implanted or delivered with a drug could allow for continuous and detailed health monitoring so disease might be managed better, turning a drug into a mlitanetional tool for diagnosis and ‘reatment For exanple, bio sensors could be attached (0 targeted drugs and linked co a mechanism that reports the bots’s eonltion Purthermor Aaccorlng to the National Insite of Health, gold nanoshells are beïng {eveloped to simultaneously image and destroy cancer cells using infrared light Nanoshells ean be designed to absorb light of differen fequencies, senerating heat Once the cancer ces take up the nanoshel’, scientists apply near infrared light thats absorbed by the nanoskels, eating an Intense feat inside the tumor that selectively lls ainor cells without clsturbing neighboring heathy cells Such a targeted delivery approseh ‘could reduce the anount of chemotherapy dey needed to hill ance ‘ells, potently reducing the side effees of eremotherapy, Medieal researchers are also exploring the use of nanomateriais to deliver ‘molecules und growth factors to promote beter healing for burns and ‘wounds that heal without scars For example, Department of Defense researchers have eonicted tess in aninvals sing naoniber wes scaffolds to teat bone, nerve, cartilage, and rouse injuries and have reported that preclinical data from the suis indicate improved healing (ther nanofibers are being developed for medical use 2 mesh barsiees to stop the flow of blood and other luis more quickly and effectively
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Personal Care, Cosmetics, and Other Consumer Products
‘Nanomaterials are curecniy belng used ina varlegy of personal care lems, ‘cosineties, and other eonstimer products.” These products chide
sunscreens that contain nanoscale ianiume dioxides and zine exiles, ‘shiek aet es physical filters that absorb UV light Because these ‘nanomaterials are smaller tha the wavelength of ight, they male
Ssunsereens iransparent instead of opaque, and they may aso alere better ‘when applied and absorb harm ultraviolet rays more effectively than conventional sunsereens, according to stakeholders and documents we xeviewed Ìn addidon, nanomaterials ace beng inconporated inta ccosmetis, suet as an antiaging cream, which allows the active Ingredients to penetrate deep into the skin where they ean be most, effectively administered, according to dhe manutacturet, Nanomaterials are also being used ina wide range of other consumer products For ‘example, companies are using carbon nanolubes a reinforce a variety of sporting goods, such a hiyele ames, tennis rackets, baseball bas, and hockey sticks, because they offer greater strength and reduced weiht, while retaining, or even inezeesing, sifiness Companies are sing other nanomaterials improve the performance of products such as ska wax nd teanis balls For example, a tanomaterial coating decreases the gS Deraneabilty in tenis balls and therefore allows the balls co maletain pressure for longer periods of me, aevording tothe compan prodielng, ‘he coating Nanomaterials fan clothing stain and water resistant, For example, one company embeds are also being use in coatings to make fabries
‘nanomaterials on the srfaee of fabrie bers, eating a cushion ofa Around ther The fabric allows sweat ta paseo, we also easing ‘surface water 10 head up aol ol off Another company has developed socks reated sith nanosiver for is sntimievobial properties
In he future, consumers may benefit from advanced applications that ‘could emerge from nanomatesal research aceurring ina variety of sectors For example, developments in Ute Wealth arena could lead to new, Dbeneticial pharmaccutic} therapies designed o treat aging and age related disease i addtion, according to documents we reviewed, researchers are working tome textiles funtional by combining "wônhferred nanomaterials with materials that react to light to create power-generating clothing and nanosilver could he used in textiles to teat
Trang 27Potential Risks to Human Health and the Environment from Nanomaterials Depend on Toxicity and Exposure, and Current Understanding of the Risks Is Limited
‘skin conditions: Researchers are also developing nano-enabled etic Surfaces thc can emave seraiches aid self marks, as Well 2s decolorize red sine spills ‘The properties of nanomaterials affect their toxiiky and, in cur, thelr risks to human health and the environment Purheemore, the isk of nanomaterials also depends onthe extent and roate of exposure to ‘nanomaterials, but eurrent understanding of nanomatena toxicity and ‘exposute is limited, according othe studies we reviewed
The Toxicity of Individut Nanomaterials May Vary According to Their Properties and Affects ‘Their Risks
‘The tonleliy ofeach wanonvaterial way vary according 10 @ Combination of ‘he individual properties ofthese materials—ineluding size, shape, surface area, al ability to reet with other ehemeals and these properties alec, ‘the potential risks posed by nanomaterials, according to some of the shudies we reviewed! The properties ofa nanomaterial may’ fer from che properties of conventionally sealed material of te same composition For ‘example, the properties of conventionally scaled gold have been ell ‘characterized: gold is metallic yellow in color and does not realy react ‘with other chemicals Asa nanoparticle, however, gold can vary i eolor Fron) red t black ad become highly reactive Te following ae examples ‘ofhow coxieity may be atecte! by de properties of nanomaterials as ‘compare with their conventionally scale! counterparts:
Size, Research assessing the role of particle size on toxicity has generally Found that some nanoscale (100 nanometers) particles and ea eause more inflammation than canventionally sealed parleles of| are more coxie
‘the same composition Specialy, some research hdicates at the toxiexy of certain sanomaterias, sue as some forms of earbon nanotubes and nanoscale tantum dioxide, may pose aris to hum health because these materials asa result of their smal siz, may be able to penetrate cell ‘wall, causing ell inflammation and poteabaly Teadg to certain
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‘damage, according to some ofthe studies we reviewed In addition, some nanomaterials mey disperse differenti into the exsironment than ‘conventionally sealed materials of the sue composition because of thelr Size Howrever, according to EPA, the stall patile size may also cause tive nanomaterials to agglomerate, which may make femore difcul for than to penetrate dey hing tissue
Shape Nanomaterials may be produced ina wide variety of shapes, including spheres, tubes, threads, and sheets, as well as more omate forms, sich as danb-bells The shape of nanomaterials may’be ronnected {othe type of heal risks they may pose For example, some carbon rnotubes resemble asbestos bers: When ishaled by people, asbestos Tihcrs ace knots o ease mesotheliom—whieh Is ecsse associated ‘wth asbestos expostre The similarity of these carbon nznontbes to asbestos fibers has cased researchers fo question exposure to sich nanomaterials may lead to asmular disease Parthermnore, asd has ‘Shore that exposing the abdominal cavity of mice to certain long eaebon nanotubes may be inked with lanamarion of the abdominal wall The hdotninal cay in mive is often used asa surrogate for understanding hove te mesothelial ining ofthe human chest easity reäet t0 sibstances
Swasinoe area ancl reactivity Nanomaterials may also be more reactive with other chemicals tha similar conventionally scaled materials because nanomaterials have a higher surface area-foanas ratio, providing more area hy weight for chemieal reactions co occur Some studies have found {har hecase ofthis increased reactivity, some manoscle parIcles may bề potentially explosive and/or photoactive ` that ls sunlight tiggees 3 ‘chemical reaction in them For example, some nanomaterials~sueh as nanoscale tani dioxide and silicon dioxide—may explode finely dispersed inthe ar and they come Into eantaet with a sufficiently strong Jgnition source However, in genera, the extent to which seh nanoscale sis may be more explosive than larger sive dusts of the same
composition is not fly known, according to the National Institute for ‘Occupational Safety aad Health, ther research has shown that particle surface area isa better predictor of toxic response to inhaled particles than s particle mass, For example, researct into nanoscale titanium dioxide in mice and rats has shown that particle surface area seemsto bea more appropriate measure for coniparng the effects of different-sized particles, provided they ate of the same ceva! structure
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Risk of Nanomaterials Is Also Affected by the Route and Extent of Exposure
Tn addition co toxiely, the risk that nanomaterials pose to hurians and the ‘environment also affected hy the rote and extent of exposure to such rraterals, Nanomaterials ean enter the human bode throug three primary routes: ination, ingestion, and dermal penetration
Inhalation isthe most common route of exposure to airborne
nanoparticles, according Co the National Institute of Ocespational Health and Safety, For example, workers may inale nanomaterials while producing them if the appropnate saety devices are nat used, while ‘constiers may inhale nanomaterials when using products containing nanomaterials, such as spray versions of sunsereens containing nanoseale ‘ianium dioxide, Aecording to officials atthe National Institutes of Health, although the vast nlorty of inaled particles enter the pulmonary trae, fecidenee from studies on laboratory animals suggest shat some inhaled ‘nenomaterials may travel via the nasa nerves tothe bran and sein access {ihe Bload, nervous system, and other onzans, according to stodies we reviewed
Ingestion of nanomaterials may occur from unintentional hand t@-month ltansfer of nanomaterials of fot the intentional ingestion of
nanomaterials” Ingestion may also accompany italation exposure because particles that are cleared from the respiratory traet can be swallowed A large fretion of nanopartietes, ater ingestion, rapidly pass ‘ut oF te body; however, according to some ofthe studies we reviewed, 2 ‘all emount may be aken up by te body ane then sagrate into organs ‘The effect ofthese sina amnainls of lngested nanomaterials is curently ‘unknown, but concerns have arisen from a growing body of evidence ‘which indicates that eerzia types of nanopardeles may cross eellulae ——
Nanomaterials may also be ubsorbed through the ki, Por example, one laboratory sd fas shown tha certath nanomaterials have penetrated layers of pigskin within 2¢ hours of exposure In adhtion, some casmesies and sursscreens—among the first commercial produets to incorporate ranomaterials—contain nanoseae dtu dioxide to snerease the ultraviolet ight-blocking power ofthe product, The nano titanium dioxide
Se oer of eponar ined re general for cin or commie exponen
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‘is believed to he less toxte than other chemicals that have been used to provide ultraviolet protection in sunscreens However, according to some fofthe shies we reviewed, coneeres have Deen raised thal nanomaterials In snsereens could penetrate damaged skin contrast, aecording (0 ‘ffciis a the National Instcates of Heal, there are several stuies that Jhave foun tle dermal penetration rom nanomaterials when applied to undamaged skin, According wo some stakeholders we spoke to, even the kuown hazards of sn exposite, sunscreens eonIahlne hangmsterals may de reasonable choices for the protection that they provide to cousters From sun exposure
In addition to the route of exposure, the extent of exposure—that isthe Frequency and magaitude—to consumers nel workers also afects the risks posed by nanomatevials Workers may be aeculentally exposed 10 rnomaterials dating the production af nanomaterials oF products ‘containing them, as wells during use, dispose! or reeling of these products At present, there is insafficlent information an te number of ‘Workers exposed to nantomaterias in the work place or the effects on human heath af sued exposure, according o the European Agency for Safely at Health at Work ly addition, ease nanomaterials have applicationsin many consumer products and the use of such materials in products is increasing, consumers have an increasing chance of exposure {oshese materials For example, consmers may now purchase appliances Sich as washitg machines coated wit silver nanomaterials purported te hall bacteria, When consters murchase seek a machine, tei coding ‘will he exposed tothe silver nanomaterials, hs increasing ther exposure Lonanomaterials Similary, consumers may now purchase socks
‘containing nanosihe, whieh expases them to this nanowatera
Aceaning (BPA officials, occupational exposure is a particular eoneerm and warrants atention beeause te exposure and risk to workers is potentially greater than the rise to consumers.”
In addition to humans, the environment may also be exposed to rranomaterials through releases into the wate, 2p, and soil, during the manufacture, use, or disposal ofthese materials For example,
nanomaterials could enter water through discharges from production ‘ellis n aldton, when nanomaterals are used in pharmaceuticals, ‘cosmetis, and sunsereens, the nanomaterials cond enter water via Ihe
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‘sewage aystem during washing, showering, or swimming afer having beew Applied ¢o the skin and may evendally end up ina waste water trealnent plant, These nanonwaterias, fanibacterial in nature an if released in ‘sufficient amounts, could potentially interfere with Veneffe! bacteria in seveage and waste Water tealment plants an could also contaminate ‘water intended for reuse, accor reviewed Moreover, some researchers have raised serious concerns that a some ofthe tudes that we antibacterial nanomaterials will pose tosieiy risks to huni healt ant “environmental systems int whieh waste prodicts are released In
addition, according to research, unused cosmetics are most kel to be tisposed of in household waste, whieh maybe incinerated, poteatially palling naromaterials into the ar, or putin alan, potentially lean ‘oat of tie lanai into the water In ddition, nanomaterials tha are ‘currently being used to teat polhited water wil result in leases of the materials into water and sol For example, iron nanoparticles are being ‘sed to Heat polluted water According to EPA officials, although tite is
known about how these partiles mave through the envizonment they are ‘expected to react with contaminants o with naturally occuring
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‘Currently, itis dieu to assess the risk of nanomaterials that are
released nto the environment because these materials are so varied and it {s dffiealt to make generalizations are released, according to EPA officials Specifically itis unclear whether about how they will behave once they
the nanomaterials will (1) stay suspended, 2) aggregate or cluster
together to form larger particles (3) dissolve or further break down, or (8) reat with natural materials found inthe environment For example, the release of earbon nanotubes, nanoparticles of ron and titanium dioxide, ‘or fullerenes—which are nanoscale spheres of earbon—into water may result in thelr agsregation, according to some ofthe studies we reviewed ‘These lager aggregates may have different toxicological properties when ‘computed to those exhibited by the original nanomaterials The rsk posed bby some nanomaterials is presumed to decrease i they aggregate because the nanomaterials may grow tothe size of conventionally sealed
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‘he environment, according 1 some ofthe smdles we reviewed Specially, some naromaterais may become atached to and continue 10 Dull up in che soi, depending on the nanonsaterial characteristics and the ‘haracteisties ofthe soil Some nanomaterials may siso bionceunvulate in ‘organists, according to EPA,
Understanding of the Risks Posed by Nanomaterials Is Limited by Several Factors,
Current understanding of the eisks that nanomaterials may pose is limited by several factors, including the limited amount of researc that has been ‘conducted to date anda lak of tools and methods needed to conduct Aieitional research Asa resll, predieting and assessing the potential Inozars, exposures, and resulting risks from nanomaterials diffealt, Although the number of stuies that have Focused on assessing the risks of _nanomaterals as inereased over the past 5 years (see fig 7), the studies completed 10 date have yielded limited risk infornstion, according 0 BPA officials and onher stakeholders that we spoke with, andl our vesiew of {hese sides, Some ofthese limitations inelude the following
"he findings rom completed toxicity studies of a nanomaterial
constructed in one manner may not be applicable to understanding che risks posed by the sane nanomaterial constructed ina different manner ‘nd, therefore, studies of simular nanomaterials may nat be comparable For example, carbon nanorutves may be prouced in several ways, each with its own potential level of toxicity so tht the reslts ofa study for one {pe af carbon nanube may Hot he comparable ro the resus ofa studs ‘ofa different type of carbon nanotube Similars, some eatly studies of ‘carbon nanotubes did not specify the Yength of the nanotubes being studied, making it iffcut to compare the results ut hose studies wit Subsenient eazbon nanotube shidles, according to stakeholders Tiss important because researchers now know that diferent nanotube lengths may pose different sks,
Trang 34Figure 7 Tre neesse Triển vợ ranh ng Raman sretyReronren Peetng
Additional effors to stud the risks from nanomaterials will also be ‘hampered because certain tools necessary to conduct these studies are lacking Specifically, according to studies we revised, reseateh on nanomaterials depends onthe availability of too, such as models or measurement technologies, to characterize or deseribe the nanomaterials nan qualities However, although some tools are avallable, the selene ‘oramnity does not cureently possess all the needed tools to da so, and it will require extensive researeh to develop hese cools Additionally, lack of ara andl appropriate models also lis our ability to study the risks posed by nanomaterials, according to some of the studies we reviewed and stakeholders that we spoke with While researchers have developed eodeh Tọt conventionally scaled chemicals ts predit thelr ‘characteristics based onthe characteristics of similar, or analogous, ‘chetscas, wo such movdels exist yet for nanomaterials Bor eximple, a mentioned earlier, fe nanoparticles may aueregate in the natural environment, foruing larger structures that may have afferent
Trang 35EPA Has Taken a Multipronged Approach to Managing the Potential Risks of Nanomaterials but Faces Various Challenges in Regulating These Materials
“oxioity of the ngnomacedals The eect of sieha small change
Ccompourids the difenity i ereating predictive models of hanomaterii EPA has taken a variety of setions(o beter understand and regulate the risks of nanomaterials, including conducting research and asking
‘companies o voluntarily provide information about the nanomaterials that thy produce or use Althougs EPA listen some regulatory action ‘under its existing satitony framework wih regard to nanomaterials, is anthony to do so varies depending on the statute tt ts usa 0 reguhie specific nanonnaterials ” Moreaver, the agency faces adelitional technical and informational challenges that may impact its aby to regulate nanomaterals efectvely
EPA Has Ongoing
Research Biforts Related to Nanomaterials
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“approaches for Wentifying and addressing any hazardous properties, while rnaintaining beneficial properties, before « nanomateral enters the ‘csirnment and (2) denify whedher, onee aranomsateril enters the “environment, i presents environmental sks, PA stated Uk plans to pursue these ohjeetives from a life eyele perspective—from the production ‘ofa nanamateria through is use in products, ad as itis disposed of or recycled, Utinatels, EPA plans to develop models and other tools to ‘enable ito predict the risks posed by various types of nanomaterials [According to the strategy EPA\s research efforts will be coordinated with those of other federal agencies, For example, EPA's laboratories collaborating with the Natioat Institue of Health to conduet research are
‘on, among other things, the health effec of carbon nanotubes, According {o BPA is researc hulls on and is consistent wit the scientific needs ‘eattied by the NNI's Nanotechnology Bevironmenial and Healt Inpiestions working group and in EPA's 2007 Nanotechnology White Pape
EPA is also coortinating with interntions! organizations, sel as the (Organisation or Economie Co-operation and Development (OECD) and ‘he Infemational Organization for Standardization (150),” on
nanomaterials research Speeificaly, the OECD established the Working Party on Manfactured Nanomaterials September 2006, with EPA as 3 ember and the initial chr ofthe working party This working party is engaged ina variety of projects to futher the understanding ofthe
properties and risks of nanoscale materials av hos to mitigate exposures and potential risks For example, one project involves a program for testing the safety of se off nanomaterials Specifically, member countries have agreed to develop certain data fora group of TẾ
anoinaterials selected by the OECD working party, i pat because they Aare in commerce ar clase co commercial use.” AS part af his efor, BPA Ins the lea for the testing of Fallerenes, single-walled earbon nanotubes, nlivalled carbon nanotubes, siker nanoparticles, and nano een
Trang 37“commitiee to develop intervtonal sandards for, among other things, ranolechnology tertninology, speeieations for reference materials, and est methodologies Under TSCA, EPA Has Regulated Some Nanomaterials as New Chemicals or New Uses, but Some Nanomaterials May Be Entering the ‘Market without EPA Review
(Over the lat years, EPA's approach for regulating nanomaterials under "TSCA has been evoking ss more information has become available on the potential isk In January 2008, EPA launched a vakentary program called the Nanoscale Material Stewardship Program, Under this program, EPA posted a notice inthe Fedora! Register asking manutaehucees and Drocessors of nanomaterials to submit existing informacion on the rranomaterials they produce or use to help EPA better understand the Ihaman health and environmental risks fom these sbstances, Thiny-one ‘companies voluntarily provided infomation on 132 nanomaterials, according to EPA officials [nts interim report on this prograi, issued in
‘anuary 2900, RFA noted that although the program provided sel information regarding certain naxionsateias in earmneree, a significant ‘amber of environmental health ud safety data gaps remain, For
‘example, ss par ofthe voluntary program, EPA estimated that companies provided information on only about 10 peteent ofthe nanomaterials that are likely to be commeteialy availabe mn addition, EPA reported th its review of data submitted through te programm nevealed instances in whieh the details of the manafaeturing, processing, and use of the nanomaterials, as well as exposure and toxiety data, were not provided This futher reshiced the nseflness ofthe information recelved because expose and toxicity data are evo of the major eategories of information that EPA had
identified as being needed to better inform its isk assessments of ‘nanomaterials, EPA cone from te low response rate that most ‘companies were not inclined ta volustarly sippy information on the nanomaterials
In anuary 3098, EPA released a document ented PSCA Innontory Siatws ‘of Nanoscale Substances—General Approneh, which addressed whether nanomaterials constituted new chemicals forthe purpase of regulation
nner TSCA TSCA provides EPA with different authorities for regulating ‘new chemicals unl existing chemicals: New chemicals are those that are not already listed on the TSCA inventory, which isa lis of ctemical Substances manufactured or processed inthe United States Bxisting ‘hemicals are those altezdy in commerce ielding aout 62,000 whieh ‘were already In commerce when FPA begs reviewing chemicals it
Ingeneral, existing chemicals ear be mannfactared or processed without ny notification to EPA By contrast, companies intending to manufeeture anew chemical must generally submit notice to EPA before
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‘manufacturing oF producing the chemical In is 2008 document, EPA Slated that 9 nanotnateral i anew chemical for purposes of regulation lider TSCA only iit does wot have the same "molecular identi” ast
‘henscal alteady on the inventory Under TSCA, a chenaial is defined in {osms of is partienlar molecular identity, Although molecular identity ss ‘ot defined inthe state, EPA considers chemicals molecular ideatities wen, for example, they represent different (o have diferent allotrapesn variant oft substance consisting of only one type of atom — ‘or isotopes” According to EPA officials, EPA generally docs not consider
the properties—such as size, shape, and reaeisty—of a chemical in ‘establishing ils melecular identity Thus, because ttaninm dioxide is alrealy listed onthe TSCA inventory, nanoscale versions of titanium ‘oxide, which have the same moleculse formals, woul not be considered ‘new chemical under TSCA, despite having a different size or shape, liferent physical and chemical propesties, and potentially eiferent risks However illerenes—a class of nanansaterals ade of spheres of ‘arhon—would be considered a new chemical hecause they eepresent diferent allotrope, or molecular arrangement of earbon atoms, Unan those chemicals already listed on the nnventory
IFEPA makes certain Rudings, on the basis af formation presented ina premanufaeture notes, tay control te manufacture, processing, tisitbution in commerce, use, and disposal ofthe chensiea The gdeney sometimes issues a consent order to the company that places conditions ‘on she se of the chemeal or reqlzes the company to generate more information on the chemicals health and envitonmental effects Since
2008, the agency has received over premanfactare natices for
nanomaterials under TSCA, according to EPA officials BPA officials also {old us tar about 20 of these aniices were toqness fullnew chemical review process based an regulatory exenyptions foe o be exempt from the ‘substances that met specific low release and exposure eriteria or whit ‘were produced at low volumes,
30A also authorizes EPA to ise rules addressing nev uses of certain anserlals—Inown ss Significant Neve Use Rules (SNUR), These ries dentfy new uses of existing eemseals that could affeet the nature oF = atoopes ae dite fone of he wane clement oi
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‘human and environmental exposure tothe substance Ifa company wants ousea eliemical iva way tha has been desianated asa significant new ‘se iL must submit a Signieaet New Use Notice to EPA For exannple, EPA determines that manufacturing a chemical in a powder form instead ‘fa lini form would be a significant new use of that eterical, the ‘company planning on manufacturing the chemical ina powder form would have to nots EPA Upon receipt of a notice, EPA hes 90 days co evaluate the intended use and i warranted to prohibit or limit it before it ocears I 2008, EPA issued two sich rules for nanomaterials, Specially, having received premanufactre notices for nanoscale versions of siloxane ‘need siiea andl alma particles, EPA determined that certain uses of these chemicals, neliding use without employing personal protective ‘equipment, asa powder, andl uses different from those described in the Dremanifacture notices, were significant new uses
In 2005, EPA entered Inco consent orders with & manufacturer ofa specific ‘pe of eathon nanotubes that placed conditions on the use of tha
_manufactrer's carbon nanotubes EPA was unable to determine the potential for human health effects of these nanomaterials hase on the Snformation available ia the peemeanutaeture notices and determined that {he uneontrlled manufactuce, impor, processing, dscrhution, use, oF disposal of these nanomterials way present an unreasonable risk to Jnaman health, Accordingly, BPA imposed exposure and release controls ‘on the manafaeture of these nanomaterials in addition to certain testing requirements, Subsequently, In November 2009, EPA proposed SNUBS for
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Jus eeated all earbon nanotubes as unique chemical substances forthe ‘purpose of isting thew on the TSCA chemical inventors In the fall of 2008, EPA announced it wonld reconsider the policy
described ints Jannary 2008 document, TSCA hnoentony Status of Nanaseule SuistancvaGeucral Ayproch, and subsequently announced ic planned to develop @ SNUR to regulate nanoscale versions af
‘conventionally sealed chemicals tht are already on the TSCA inventory as significant new use ofthat chemical The ageney intends Co propose this rein December 200 EPA stated the ageney wonld determine the existing uses of nanomaterials by using information submited through the ‘voluntary Nanoscale Materials Slewardsip Prograr and other sores EPA officials told us that issuing a SNUR would allow the agency to regilate nano versions of chemicals already on the TSCA inventory the same way it would regulate face in suing such @ SNUR a new chemical One problem that EPA may is hat mans ses of nanomaterials are no Tonge new because nanomaterialsare rapidly entering the mazket, accorlng to stakeholders we spoke with
TSCA also gives EPA authority to sue rules requiring companies to Smit cera information about chemicals EPA plans rule for nanomaterials that sould require manufacturers to prove co isse one sch information on production volume, methods of manufacture and
processing and exposure and release, as well as available health and Safely studies Evaluation of is information will provide BPA with an ‘opportunity to consider appropriate aetion under TSCA tusteasonable risks to hums health or the environment, according to BPA, to reduce
This rule may also help them collect information on nanomaterials not covered by the SNUR discussed above EPA intents to propose this re in December 210 Ths, however, raises the concera that, the meantime nanomaterials may be encering dhe market without the satin these materials may ment Furthermore, stakeholders and EPA oficiats point ‘ut that the completeness of information collected under a reporting rule nay be limited hecause the current definition of small manutaerurers and processors nay exempt numerous manufacirers and processors of ‘nanomaterials from such res Some sakeholders told us this exemption say be particulary limiting in the case of nanomaterials beeause much ‘nanomatevial development is being done by small startup companies