Possibleexposureroutesfornanoparticles, nanofibers & nanotubes tohumansare:
A. dermalcontact&thenabsorbedbytheskin
B. inhalationviatheair(breathingin)
C. ingestionviathefoodintake/diet
D. accidentalinjection
Whichofthefollowingstatementsabouttherelationshipsbetweenexposureroutesofnanoparticlesandtheirhealthrisksarecorrect?
A. Exposurestonanomaterialsmayoccurthroughinhalation,dermalcontact,accidentalinjection,&ingestion,theriskincreaseswithdurationofexposure&theconcentrationsofnanoparticlesinthesampleorair.
B. Inhalationpresentsthelowestexposurehazard.
C. Nanomaterialssuspendedinasolutionorslurryposealesserhazard,however,sonication,shaking,stirring,pouring,orsprayingcanresultininhalationexposure.
D. Nanoparticlesthatarefixedwithinamatrixposetheleasthazardaslongasnomechanicaldisruption,suchasgrinding,cutting,orburning,occurs.
Theethicalimplicationsofnanotechnologyare:
A. Noreliableinformationcanproperlyreflectonthehealth-related,ecological,ethical&socialimpactsofnanotechnology.Theethicalissuesarisingfromtheapplicationsofnanotechnologyarenumerous&complex.
B. Nanotechnologyisdepictedeitherasthefuturesolutiontoworldhealthproblemsorthefuturecauseofagreatecologicaldisaster.Theethicaldebateonnanotechnologyhighlightstheoscillationbetweentheconsequentialist&deontologicalapproach,wellknowninbioethics.
C. Theadvanceswithinnanotechnologyledtodebatesontheethicalimplicationsofitsapplications,includingequity,benefitdistribution,&environmentalimpact.
D. Nanotechnologynotonlyentailsepistemicrupture,butintroducesnewlaws&structuresofknowledge,ornewcognitivecategories.Whetherproceedingfromtheperspectiveofnanoethics,thediscussionregardingtheethicalimplicationsofnanotechnologyrevealsthatthequestionsdonotariseonlyfromwithinthesocialsciences.
TheNanoscience&Nanotechnologies:Opportunities&UncertaintiesbyRoyalSociety&RoyalAcademyofEngineering(2004)oftheUKdeclaresthat:
A. Manyapplicationsofnanotechnologiesposenonewhealthorsafetyrisks.Inassessing&managinganyriskitisnecessarytounderstandboththehazard&theexposurepathways.Somemanufacturednanoparticles&nanotubesarelikelytobemoretoxicperunitmassthanparticlesofthesamechemicalsatlargersize&willthereforepresentagreaterhazard.Thetoxicityisduetotherelativelygreatersurfaceareaofnanoparticles,givenequalmass,&theprobableabilitytopenetratecellsmoreeasily&inadifferentway.Toposearisk,thesenanoparticlesmustcomeintocontactwithhumansortheenvironmentinaform&quantitythatcancauseharm.
B. Humansinhaleverymanypollutantnanoparticles(millionsperbreath)producedastheproductsofcombustion.Shape&surfacecoatingsofnanoparticles&nanotubeswillalsoinfluencetoxicity.Dermalexposureispredominatelythroughtheuseofcosmeticssuchassunscreensthatcontainnanoparticlesoftitaniumdioxide.Heretheissueiswhethertheycanpenetratetheprotectivelayersoftheskin&thencausedamagethroughtheproductionoffreeradicalsthatcandamagecells.Thereislittleevidenceinthepublicdomainaboutpenetrationoftheskinbythenanoparticlesmostcommonlyusedincosmetics.
C. Thereisvirtuallylittleevidenceavailabletoallowthepotentialenvironmentalimpactsofnanoparticles&nanotubestobeevaluated.Nanoparticles&nanotubesthatpersistintheenvironmentorbioaccumulatewillpresentanincreasedrisk&shouldbeinvestigated.Wehaverecommendedthatthereleaseofnanoparticulatestotheenvironmentbeminimizeduntiltheseuncertaintiesarereduced.Awiderangeofusesfornanotubes&nanoparticlesisenvisagedthatwillfixthemwithinproducts.
D. Theexplosionofdustcloudsofcombustiblematerialisapotentialhazardinseveralindustries.Thereareuncertaintiesabouttheriskofnanoparticulatescurrentlyinproductionthatneedtobeaddressedimmediatelytosafeguardworkers&consumers&supportregulatorydecisions.
Potentialundesired(unwanted)effectsofdrugnanocarriersinclude:
A. organaccumulationinthebody
B. activeinteractionswithbloodcomponentsinthebody
C. cytotoxicity,reproductivetoxicity,carcinogenicity,&immunogenicity
D. damagetotargetorganssuchasliver,lung,kidneys,brain,orheart