O
pen
A
rchive
T
OULOUSE
A
rchive
O
uverte (
OATAO
)
OATAO is an open access repository that collects the work of Toulouse researchers and
makes it freely available over the web where possible.
This is an author-deposited version published in :
http://oatao.univ-toulouse.fr/
Eprints ID : 19897
To link to this article : DOI :
10.1016/j.copbio.2016.11.024
URL :
https://doi.org/10.1016/j.copbio.2016.11.024
To cite this version : Mottier, Antoine and Mouchet, Florence
and Pinelli, Eric and Gauthier, Laury and Flahaut, Emmanuel
Environmental impact of engineered carbon nanoparticles: from
releases to effects on the aquatic biota. (2017) Current Opinion in
Biotechnology, vol. 46. pp. 1-6. ISSN 0958-1669
Any correspondence concerning this service should be sent to the repository
administrator:
staff-oatao@listes-diff.inp-toulouse.fr
Environmental
impact
of
engineered
carbon
nanoparticles:
from
releases
to
effects
on
the
aquatic
biota
Antoine
Mottier
1,2,
Florence
Mouchet
1,2,
E´ric
Pinelli
1,2,
Laury
Gauthier
1,2and
Emmanuel
Flahaut
3,4Nano-ecotoxicologyisanemergingsciencewhichaimsto assesstheenvironmentaleffectofnanotechnologies.The developmentofthisparticularaspectofecotoxicologywas madenecessaryinordertoevaluatethepotentialimpactof recentlyproducedandusedmaterials:nanoparticles(NPs). AmongallthetypesofNPs,carbonnanoparticles(CNPs) especiallydrawattentiongivingtheincreasingnumberof applicationsandintegrationintoconsumerproducts.However thepotentialimpactsofCNPsintheenvironmentremainpoorly known.Thisreviewaimstopointoutthecriticalissuesand aspectsthatwillgovernthetoxicityofCNPsintheenvironment.
Addresses
1ECOLAB,Universite´ deToulouse,CNRS,INPT,UPS,France 2
ENSAT,Avenuedel’Agrobiopoˆle,F-31326Castanet-Tolosan,France
3CIRIMAT,Universite´ deToulouse,CNRS,INPT,UPS,UMR
CNRS-UPS-INPN!5085,Universite´ Toulouse3PaulSabatier,Baˆt.
CIRIMAT,118,routedeNarbonne,31062Toulousecedex9,France
4CNRS,InstitutCarnotChimieBalardCIRIMAT,F-31062Toulouse,
France
Correspondingauthors:Gauthier,Laury(laury.gauthier@univ-tlse3.fr), Flahaut,Emmanuel(flahaut@chimie.ups-tlse.fr)
Introduction
Nanoparticles(NPs)areusuallydefinedasobjectswithat leastonedimensionbetween1and100nm.Theycanbe released into the environment from natural (volcanoes, forestfires, etc.) or anthropogenic (brakepads residues, welding,combustion,etc.)sources.Amonganthropogenic nanoparticles, engineered nanoparticles (ENPs) have recentlyemergedandquicklyshownaveryfast develop-ment [1]. Thefields ofapplications ofENPs aremany (automobile,medicine,optics,electronics,etc.)andENPs arenowintegratedindailylifeconsumerproducts.The
number of products integrating nanoparticles was esti-matedbetween1814[2"]and2332[3]andwasin2015 30-foldmoreimportantthanin2005[2"].Amongthewide variety of ENPs, Carbon-based nanoparticles (CNPs) representaspecificclass,especiallyinterestinginterms of rapid development and applications. Although all composed of carbon atoms, the different hybridization of the C–C bonds gives them very specific physical properties.CNPscanbedistinguishedbetween0D: full-erenes, onion-like carbon, carbon dots, nanodiamonds; 1D:nanofibers,nanotubesandnanohorns;2D:multilayer graphitic nanosheets, graphene nanoribbons, and grapheneandrelatedmaterials(GRMs).CNPswerefirst describedin1985withC60fullerene[4]butmost
applica-tions came later with carbon nanotubes (CNTs) in 1991 [5] and graphene more recently [6]. Given their unique properties, GRMs are currently subject to important research efforts to improve their large scale production [7,8]. CNPs are already used in daily life products(nanocomposites,paints,energystorage,waste water treatment [9], etc.). Depending on data sources, between89and217consumerproductsintegrate carbo-naceous nanomaterials[2",3] anditis likelythat CNPs willbereleasedintheenvironmentduringthelifecycle of manufactured products [9–11]. This review aims to reportthestateoftheartdealingwithCNPs effectson the environment with a special focus on the aquatic environmentbecauseof itsabilitytoconcentrate pollu-tion.Anemphasiswillbemadeonthefateanddetection ofCNPs inthe environmentandin complexbiological matrices.
Carbonnanoparticlesinthe environment
The risk posed by a xenobiotic in the environment is definedastheresultof environmentalexposureandits intrinsicdanger.Thereleases andfatewillgovern con-centrationsofCNPsintheenvironmentandarethuskey aspectsthatwilldeterminetheirecotoxicity.
AnalyticalmeasurementsofCNPsincomplexmatrix Severalexperimentaltechniquesarecurrentlyusedand developed in order to directly measure environmental concentrationsofCNPs.Mosttypesofnanoparticlessuch asmetalnanoparticlescan bemore easilydetectedand quantified in complex organic matrix (especially using single particles inductively-coupled plasma quadrupole mass spectrometer: sp-ICP-MS or synchrotron) [12].
reportedenvironmentalpredictedconcentrations(EPCs) in surface water between 0.23ng/L (Q0.15=0.17ng/L;
Q0.85=0.35ng/L) in 2012 [19] and 0.28ng/L
(Q0.15=0.04ng/L;Q0.85=0.65ng/L)in2014[20""].
Simi-larlysedimentconcentrationswereestimatedandranged from 0.79ng/L (Q0.15=0.61ng/L; Q0.85=1.2ng/L) in
2012[19]to6.34ng/L(Q0.15=4.32ng/L;Q0.85=9.24ng/
L) in2014[20""].Withanexpectedcontinuousincreasein needs, the concentration of CNPs will increase in all environmentalcompartments.Althoughveryuseful,these predictionsarenotvalidatedbyanalyticalmeasurements [22]andimprovementsareneededinbothfields[23].
Modelingmethodsarealsousedtodeterminethefateof engineeredCNPs[24],whichisgovernedbybothbiotic andabioticprocesses[25].Thesetransformationscould drasticallychangethebehaviorandthebioavailabilityof CNPs [9,15,26]. The review by Mitrano et al. gives a completeoverviewoftheagingandtransformationsthat CNTs mayexperience in theenvironmentand during the lifecycleofmanufacturedproducts[9].Becauseof transformations,thebehaviorandphysicalpropertiesof pristineCNPsmightbecompletelydifferentfollowing their release. A complete characterization of nanoma-terials has become a requirement to publish nano-ecotoxicological data.There is however some ambiva-lencebetweentheneedoffull characterizationof pris-tine CNPs(just manufactured) and transformations of these particles after interaction with exposure media and organisms during ecotoxicological trials. Physico-chemical characteristics are necessary to understand toxicological phenomena but, as reliable analytical
measurements and detection of CNPs in complex
However, the intrinsic nature of CNPs but also many technologicalbarrierspreventtheirreliabledetection in carbon-richcomplexenvironmentalmatrices: quantifica-tionof CNPs is often moredifficult than lookingfor a needleinahaystack.AmongCNPs,arealeffortwasput onthedetectionofCNTs.Recentreviews[13"",14,15,16] identifiedavailabletechnologiesforextraction(adozen) andmeasurement(aroundtwenty) ofCNPsinboth the environmentandinorganismsbutalsohighlightedallthe limitations of these techniques. The lack of hindsight concerningtherobustnessofthesemethodsbutalsothe lackofreproducibility ispointedout.Howeverthermal methodssuchasmicrowave-inducedheating(MIH)[17] orPTA(programmedthermalanalysis)seempromising and have also been successfully used to measure gra-pheneandgraphene oxideincomplex organic matrices [18].
Releaseandfate
Release of CNPs into the environment could occur at each stage of the life cycle of manufactured nano-products:production, use, waste, anddisposal [9,10,19] (Figure1).Withoutreliableandrobustanalyticalmethods fordetectingtraceconcentrationsofCNPs(apartfromthe specialcaseofisotopiclabelingwith13Cand14C), mathe-maticalmodelingisa usefultool topredictreleasesand environmentalconcentrations.Studiesmodelingthe CNPs releasemainlyfocusedonCNTsaswellasgraphenemore recently,andfewinformationisavailableforothertypesof CNPs[11,19,20"",21].Availabledatashowedthat world-wideproduction ofCNTs is closeto 3kt/year [10]and Europeanproductioncontributesabout0.38kt/year[19]. Based on European production data, latest estimations
Figure1
Effects on biota?
Chemical & biological transformations? Concentrations in the environment?
Transfers? CNPs releases ? Production Wastes Recycling Use of commercial products Primary producers Primary consumers Secondary consumers
Current Opinion in Biotechnology
matrices are still improving and mostly do not allow characterizationafterwards,theneedofcharacterization data of pristine materials sometimes sounds pointless. Transformations and aging of CNPs are challenging researchtopicsbuttheyareoffundamentalimportance in order to realistically assess the effects of CNPs in complex environments(Figure1).
Assessment ofCNPstoxicityinthe biota
Historically,assessmentofCNPsecotoxicologicaleffects relied upon methodologies used for ‘classical contam-inants’ (i.e. chemicals). For‘new’ contaminants such as CNPs,thesetestmethodshaveinitiallyplayedarolein ordertodefinetoxicitythresholds.Duetorecent devel-opmentsanduses,recentstudiesonCNPs’ ecotoxicolog-ical potential mainly focused on the effects of CNTs, grapheneandGRMs.
Photosyntheticmicroorganisms areatthe base ofmany trophic chains. Toxic effects on these micro-organisms couldleadto drasticeffects onthe wholetrophicchain (Figure1). These organismsarethus a criticalgroup to lookatforassessingtheeffectsofCNPsonthe environ-ment. Effects of twodifferent types of CNTs (double
walled: DWCNTs and multiwalled: MWCNTs) were
assessed on the benthic diatom Nitzschia palea [27,28]. Resultsshowedthatenvironmentallyrealistic concentra-tionsofnaturalorganicmatter (NOM)usedasa disper-sant could increase the short term growth inhibition induced by CNTs. Dispersion of CNPs is essential to characterizeasitwillgreatlydeterminethebioavailability oftheseparticles.Asecondessentialissueconcernsthe secretion of extracellular polymeric substances (EPS) whichhasa protectiverole againstCNTsandhelpsfor growthrecovery(Figure2).FurthermoretheEPS-coated
CNTs could potentially move to higher trophic levels (Figures1and2)ofthefoodchain,afterbeinggrazedby organisms.Oxidizednanomaterials(carboxylic function-containing single walled CNTs: C-SWCNTs and gra-pheneoxide:GO)exhibitadifferenttoxicologicalprofile with generation of reactiveoxygen species (ROS) from 0.01mg/L in the green algae Chlorella vulgaris [29]. Oxidative damages were also detected in the protozoa Euglena gracilis exposed to GO [30]. CNPs effects on photosynthetic organisms also depend on the intrinsic natureoftheCNPsandonthephysiologyandanatomyof theseorganisms.Forinstance,oxidized particlesappear moretoxicandareassociatedwithoxidativestress.Some characteristics,suchasthepresenceofthecellularwallor thesecretionofEPSseemtomakealgaemoreresistant [27–29]comparedtootherorganisms[30].Thequestion oftheroleofoxygen-containingfunctionsisstilldebated becausenotonlythismodifiesthe surfacechemistryon theCNPsandthustheirsurfacechargedependingonthe pH,butitalsocontributestomakethemmucheasierto disperseinwater.
Amphibian modelssuchas Xenopuslaevisarewell char-acterized(genetics,developmentandphysiology)andare very relevant candidates for ecotoxicology assessment. X.laevis wasusedto assessgenotoxicityandtoxicity of CNPsusingstandardizedprocedures[31–33].Ifoxidative stress and DNA damages (repairable) were evidenced aftershorttermexposure,CNTsexhibitednogenetoxic potential since no micronuclei (thus non-repairable damages) were observed after a 12-day exposure. Howevergrowthinhibitionwasobservedathigh concen-trations (from 10mg/L). Growth is a crucial parameter whose measurement integrates all modifications and disturbances undergone by an organism. Based on
Figure2
(a) (b)
10 µm 100 nm
Current Opinion in Biotechnology
(a)ScanningelectronmicroscopyimagesofNitzschiapalea(darkarrow)withextracellularpolymericsubstances(whitearrow)afterexposureto DWCNTs.(b)Scanningelectronmicroscopyimagesofexopolymericsubstances(EPS)(whitearrow)andCNTsembeddedbyEPS(darkarrow).
Classical monospecific tests reveal toxic effects at con-centrationsfarhigherthanthepredictedones.However severallimitationsshouldbetakenintoaccount suggest-ingthatthepotentialimpactmaybehigherthan expect-able. The use of the classical approach of mass-based concentration as the favorite metrics to express and comparetoxicityresultsshouldevolve,andsurface-based concentration should be seriously considered instead, especially in the case of CNPs. Ecotoxicology should move from the classical ‘toxicology’ approach toward a morerelevant‘eco’evaluationofCNPs’impacts. Identi-fication of specific toxic effects remains unavoidableto understand the mechanisms of intoxication of living systemsbutthesestudiesmustbecompletedwithmore complex butalsomorerealisticexposuresreflectingthe real environment. It may allow to uncover toxicity at levelswherenoeffectscouldbeobserveduntilnowwith simplerexposuremethodsliketheclassicalsinglespecies testsystems[41].Finallyweshouldgotowardtheuseof integrated biomarkers and approaches (i.e. biodegrada-tion, growth) reflecting allthe disturbances inducedby CNPs at lower levels of organization. This will give clearer responses for the environmental risks posed by CNPs,andnanoparticlesingeneral.
Fundingsources
Theresearchleadingtotheseresultshasreceived
fund-ing from the European Union Seventh Framework
Program under grant agreement n!604391 Graphene
Flagship.
Conflict ofinterest
Theauthorsdeclareno competingfinancialinterest.
Acknowledgements
WegratefullythankDr.LaurentVerneuilfortheSEMimagesusedin
Figure2.WethanktheEuropeanUnionSeventhFrameworkProgram undergrantagreementn!604391GrapheneFlagshipforfundingthis
research.
References andrecommendedreading
Papersofparticularinterest,publishedwithintheperiodofreview, havebeenhighlightedas:
" ofspecialinterest "" ofoutstandinginterest
1. PiccinnoF,GottschalkF,SeegerS,NowackB:Industrial productionquantitiesandusesoftenengineered
nanomaterialsinEuropeandtheworld.JNanopartRes2012, 14.
2. "
VanceME,KuikenT,VejeranoEP,McGinnisSP,HochellaMF, HullDR:Nanotechnologyintherealworld:redevelopingthe nanomaterialconsumerproductsinventory.BeilsteinJ Nanotechnol2015,6:1769-1780.
Inthisresearcharticletheauthorsprovidethemostrecentdataforthe marketing anddistributionofnano-enabledproductsincludingCNPs. Key informations concerning the integration of CNPs in consumer’s productsareprovided:categoriesandnumbersofnano-enabled pro-ducts, locationsof nanomaterials in consumer products,as well as potentialexposurepathways.
3. TheNanodatabase;URL:http://nanodb.dk/.
publications in the field of respiratory nano-toxicology [34] we recently evidenced that surface area of CNPs
(DWCNTs, MWCNTs, nanodiamonds and few layer
graphene)islikelytobethemainparameterdetermining thegrowthinhibitioninX. laevislarvae [35"]. Aspecial focusshould be madein thefuture on theuse of non-classicaldosemetricswhichcouldallowuncoveringsome toxicologicalprocessesbecausemass-basedconcentration isgenerallynotappropriate.
Toxicitydata of CNPsin single species tests couldbe gatheredinordertomathematicallymodelpredictedno effectconcentrations(PNECs)forthewholebiota.Using probabilisticspeciessensitivitydistribution(pSSD),Coll etal.derivedPNECsforCNTsandfullerenes[36].The PNECs values for these two CNPs were respectively 55.6mg/L (39.9–78.0) and 3.84mg/L (2.7–5.3). Using thesametype ofapproach(SSD),HC5 (predicted
con-centrationatwhich5%ofspeciesareharmed)valueswere calculatedforfullerenesandCNTsandrangedbetween 0.2and5mg/L, whichis also far abovePECs [37]. To date,PNECs values arefarmore importantthan PECs andbasedontheseapproaches,environmentaleffectsof CNPsseem limited.
Transformationsandagingarekeypointstofullyassess theenvironmentalimpactofCNPs.Classical ecotoxico-logicalstudiesusingsingle-species(i.e.normalizedtest) couldhelptounderstandtoxicitymechanismsoreffecton aparticulartaxa.Howeverthereisalackofenvironmental relevanceusingsuchtestsandcriticalparameterssuchas biotransformation,bioaccumulation, biomagnification or effectsofabiotic factorsareignored. Complexexposure systemsarethusincreasinglyusedtoassesstheeffectsof NPs [38]. The range from indoor trophic chains and multispeciesexposurestooutdoormicroandmesocosms exposures[39"]. Thesestudiesallow experimental con-ditions closer to the real ecosystem however with less control of both biotic and abiotic parameters. These complexsystemswereusedtoassesstheeffectsofvarious typesofnanomaterials[40–43]butonlyonepublicationis availableforCNPs[44],revealingthelowmobilityand bioavailabilityofCNTsinaquaticecosystems, whereas highpersistenceinsedimentwasobserved.
Conclusions
Mathematical modeling studies have shown that pre-dictedenvironmentalconcentrationsareexpectedtobe quitelowandtypicallycloseto1ng/L.Sinceapplications andproductionofCNPsareincreasing,itisexpectedthat environmental concentrations will also increase. The biggest challenges concern the direct measurement of CNPs in complex environmental matrices in order to validate calculated concentrations. Progresses in both modelingandanalytical measurement areneeded fora trustworthyassessment of the environmental impact of CNPs.
4. KrotoHW,HeathJR,O’BrienSC,CurlRF,SmalleyRE:C60: buckminsterfullerene.Nature1985,318:162.
5. IijimaS:Helicalmicrotubulesofgraphiticcarbon.Nature1991, 354:56-58.
6. NovoselovKS,GeimAK,MorozovSV,JiangD,ZhangY, DubonosSV,GrigorievaIV,FirsovAA:Electricfieldeffectin atomicallythincarbonfilms.Science2004,306:666-669.
7. GrapheneFlagship;URL:http://graphene-flagship.eu/. 8. ISBN:978-0-323-37521-4Copyrightã
2015ElsevierInc. 92pages.
9. MitranoDM,MotellierS,ClavagueraS,NowackB:Reviewof nanomaterialagingandtransformationsthroughthelifecycle ofnano-enhancedproducts.EnvironInt2015,77:132-147.
10. KellerAA,McFerranS,LazarevaA,SuhS:Globallifecycle releasesofengineerednanomaterials.JNanopartRes2013,15.
11. PetersenEJ,ZhangL,MattisonNT,O’CarrollDM,WheltonAJ, UddinN,NguyenT,HuangQ,HenryTB,HolbrookRDetal.: Potentialreleasepathways,environmentalfate,and ecologicalrisksofcarbonnanotubes.EnvironSciTechnol2011, 45:9837-9856.
12. LarueC,Castillo-MichelH,SteinR,FayardB:Innovative combinationofspectroscopictechniquestoreveal nanoparticlefateinacropplant.ActaPartBAt2016,119:17-24.
13. ""
PetersenEJ,Flores-CervantesDX,BucheliTD,ElliottLCC, FaganJA,GogosA,HannaS,Ka¨giR,MansfieldE,BustosARM etal.:Quantificationofcarbonnanotubesinenvironmental matrices:currentcapabilities,casestudies,andfuture prospects.EnvironSciTechnol2016http://dx.doi.org/10.1021/ acs.est.5b05647.
Thisrecentreviewlistsalltheavailableanalyticalmethodsforextraction andquantificationof CNTs incomplexorganic matrices.Thisallows havingaclearandcompleteoverviewoftheavailableanalyticaltools, withstrengthsand weaknessesinherenttoeachmethod (i.e.limitof detection,ease of use, etc.).Furthermore, the authorsprovide case studieswithdifferentscenariosinordertodescribethemethodsthat mayofferthemostsuitabletechniquesforangivenpurpose. 14. Herrero-LatorreC,Alvarez-MendezJ,Barciela-GarciaJ,
Garcia-MartinS,Pena-CrecenteRM:Characterizationofcarbon nanotubesandanalyticalmethodsfortheirdeterminationin environmentalandbiologicalsamples:areview.AnalChim Acta2015,853:77-94.
15. HuX,SunA,MuL,ZhouQ:Separationandanalysisofcarbon nanomaterialsincomplexmatrix.TrACTrendsAnalChem2016, 80:416-428.
16. JastrzebskaAM,OlszynaAR:Theecotoxicityofgraphene familymaterials:currentstatus,knowledgegapsandfuture needs.JNanopartRes2015,17.
17. BourdiolF,DubucD,GrenierK,MouchetF,GauthierL,FlahautE: Quantitativedetectionofcarbonnanotubesinbiological samplesbyanoriginalmethodbasedonmicrowave permittivitymeasurements.CarbonNY2015,81:535-545.
18. DoudrickK,NosakaT,HerckesP,WesterhoffP:Quantificationof grapheneandgrapheneoxideincomplexorganicmatrices. EnvironSciNano2015,2:60-67.
19. SunTY,GottschalkF,Hungerbu¨hlerK,NowackB: Comprehensiveprobabilisticmodellingofenvironmental emissionsofengineerednanomaterials.EnvironPollut2014, 185:69-76.
20. ""
SunTY,Bornho¨ftNA,Hungerbu¨hlerK,NowackB:Dynamic probabilisticmodelingofenvironmentalemissionsof engineerednanomaterials.EnvironSciTechnol2016, 50:4701-4711.
Thismathematicalmodelingstudyprovidesthemostrecentassessment todateconcerningtheconcentrationsofCNTsindifferentenvironmental compartment.AsdirectdetectionofCNPsbyanalyticaltoolsstillneed improvement,thisstudyallowsapredicted overviewofthe potential concentrationsinwater.Combinedwithsensitivityassessmentof organ-ismstoCNPs,thedataprovidedinthisstudyarethusveryvaluablefor environmentalriskassessmentofCNPs.
21. SunTY,ConroyG,DonnerE,Hungerbu¨hlerK,LombiE,NowackB: Probabilisticmodellingofengineerednanomaterialemissions totheenvironment:aspatio-temporalapproach.EnvironSci Nano2015,2:340-351.
22. HarperS,WohllebenW,DoaM,NowackB,ClancyS,CanadyR, MaynardA:Measuringnanomaterialreleasefromcarbon nanotubecomposites:reviewofthestateofthescience. JPhysConfSer2015,617:12026.
23. NowackB,BaaloushaM,Bornho¨ftN,ChaudhryQ,LeadJ, MitranoDM,DerKammerV,Wontner-smithT:Progresstowards thevalidationofmodeledenvironmentalconcentrationsof engineerednanomaterialsbyanalyticalmeasurements. EnvironSciNano2015,2:421-428.
24. DaleAL,CasmanEA,LowryGV,LeadJR,ViparelliE,BaaloushaM: Modelingnanomaterialenvironmentalfateinaquaticsystems. EnvironSciTechnol2015,49:2587-2593.
25. DwivediAD,DubeySP,SillanpaaM,KwonYN,LeeC,VarmaRS: Fateofengineerednanoparticles:implicationsinthe environment.CoordChemRev2015,287:64-78.
26. BundschuhM,SeitzF,RosenfeldtRR,SchulzR:Effectsof nanoparticlesinfreshwaters:risks,mechanismsand interactions.FreshwBiol2016,61:2185-2196http://dx.doi.org/ 10.1111/fwb.12701.
27. VerneuilL,SilvestreJ,RandrianjatovoI,Marcato-RomainC-E, Girbal-NeuhauserE,MouchetF,FlahautE,GauthierL,PinelliE: Doublewalledcarbonnanotubespromotetheoverproduction ofextracellularprotein-likepolymersinNitzschiapalea:an adhesiveresponseforanadaptiveissue.CarbonNY2015, 88:113-125.
28. VerneuilL,SilvestreJ,MouchetF,FlahautE,BoutonnetJ-C, BourdiolF,BortolamiolT,Baque´ D,GauthierL,PinelliE: Multi-walledcarbonnanotubes,naturalorganicmatter,and thebenthicdiatomNitzschiapalea:“astickystory”. Nanotoxicology2014,5390:1-11.
29. HuX,OuyangS,MuL,AnJ,ZhouQ:Effectsofgrapheneoxide andoxidizedcarbonnanotubesonthecellulardivision, microstructure,uptake,oxidativestress,andmetabolic profiles.EnvironSciTechnol2015,49:10825-10833.
30. HuC,WangQ,ZhaoH,WangL,GuoS,LiX:Ecotoxicological effectsofgrapheneoxideontheprotozoanEuglenagracilis. Chemosphere2015,128:184-190.
31. SariaR,MouchetF,PerraultA,FlahautE,LaplancheC, BoutonnetJ-C,PinelliE,GauthierL:Shorttermexposureto multi-walledcarbonnanotubesinduceoxidativestressand DNAdamageinXenopuslaevistadpoles.EcotoxicolEnvironSaf 2014,107:22-29.
32. BourdiolF,MouchetF,PerraultA,FourquauxI,DatasL,GancetC, BoutonnetJ,PinelliE,GauthierL,FlahautE:Biocompatible polymer-assisteddispersionofmultiwalledcarbon nanotubesinwater,applicationtotheinvestigationoftheir ecotoxicityusingXenopuslaevisamphibianlarvae.CarbonNY 2012,54:175-191.
33. MouchetF,LandoisP,PuechP,PinelliE,FlahautE,GauthierL: Carbonnanotubeecotoxicityinamphibians:assessmentof multiwalledcarbonnanotubesandcomparisonwith double-walledcarbonnanotubes.Nanomedicine2010,5:963-974.
34. StoegerT,ReinhardC,TakenakaS,SchroeppelA,KargE,RitterB, HeyderJ,SchulzH:Instillationofsixdifferentultrafinecarbon particlesindicatesasurfaceareathresholddoseforacute lunginflammationinmice.EnvironHealthPerspect2006, 114:328-333.
35. "
MottierA,MouchetF,LaplancheC,CadarsiS,LagierL,Arnault J-C,GirardHA,Leo´nV,Va´zquezE,SarrieuCetal.:Surfaceareaof carbonnanoparticles:adosemetricforamorerealistic ecotoxicologicalassessment.NanoLett2016,16:3514-3518.
Byusingamethodologypreviouslydescribedinaerialnanotoxicology studies,thisresearcharticlehighlightedtheimportanceofusing “non-classical”dosemetricsforstudyingtheecotoxicologicaleffectsofCNPs. Theauthorsevidencedusinganamphibianmodelthatthetoxicityof differentkindsCNPsismainlygovernedbysurfacearea.Moreoverthe differenttypesofCNPscouldbeconsideredasonewhentheirtoxic
effects are compared based on surface area concentrations, even makingpossibletopredictthepotentialtoxicity(growthinhibition). 36. CollC,NotterD,GottschalkF,SunT,SomC,NowackB:
Probabilisticenvironmentalriskassessmentoffive nanomaterials(nano-TiO2,nano-Ag,nano-ZnO,CNT,and fullerenes).Nanotoxicology2015,5390:1-9.
37. GarnerKL,SuhS,LenihanHS,KellerAA:Speciessensitivity distributionsforengineerednanomaterials.EnvironSci Technol2015,49:5753-5759.
38. AuffanM,TellaM,SantaellaC,BroussetL,Paille`sC,BarakatM, EspinasseB,ArtellsE,IssartelJ,MasionAetal.:Anadaptable mesocosmplatformforperformingintegratedassessments ofnanomaterialriskincomplexenvironmentalsystems.Sci Rep2014,4:5608.
39. "
BourA,MouchetF,SilvestreJ,GauthierL,PinelliE:
Environmentallyrelevantapproachestoassessnanoparticles ecotoxicity:areview.JHazardMater2015,283:764-777.
Inthisreviewtheauthorslistthemostrecentapproachesforan envir-onmentallyrelevantevaluationofNPsecotoxicity.Thisreviewhighlights theimportanceof“dustedoff”ecotoxicologywiththeuseofcomplex exposuresystemsandintegratedbiomarkersfortheevaluationofthe impactofNPs.
40. BourA,MouchetF,VerneuilL,EvaristeL,SilvestreJ,PinelliE, GauthierL:ToxicityofCeO2nanoparticlesatdifferenttrophic
levels—effectsondiatoms,chironomidsandamphibians. Chemosphere2015,120:230-236.
41. BourA,MouchetF,CadarsiS,SilvestreJ,VerneuilL, Baque´ D,ChauvetE,BonzomJ-M,PagnoutC,ClivotHetal.: ToxicityofCeO2nanoparticlesonafreshwaterexperimental trophicchain:astudyinenvironmentallyrelevantconditions throughtheuseofmesocosms.Nanotoxicology2015, 5390:1-11.
42. BuffetPE,Zalouk-VergnouxA,ChaˆtelA,BerthetB,Me´taisI, Perrein-EttajaniH,PoirierL,Luna-AcostaA,Thomas-GuyonH, Risso-deFaverneyCetal.:Amarinemesocosmstudyonthe environmentalfateofsilvernanoparticlesandtoxicityeffects ontwoendobenthicspecies:theragwormHediste
diversicolorandthebivalvemolluscScrobiculariaplana.Sci TotalEnviron2014,470–471:1151-1159.
43. BuffetP,RichardM,CauposF,VergnouxA,Perrein-ettajaniH, Luna-acostaA,AkchaF,AmiardJ,Amiard-triquetC,GuibboliniM etal.:AmesocosmstudyoffateandeffectsofCuO nanoparticlesonendobenthicspecies(Scrobiculariaplana, Hedistediversicolor).EnvironSciTechnol2013,47(3): 1620-1628.
44. SchierzA,EspinasseB,WiesnerMR,BisesiJH,Sabo-AttwoodT, FergusonPL:Fateofsinglewalledcarbonnanotubesin wetlandecosystems.EnvironSciNano2014,1:574-583.
