2025離開海岸：海洋塑料替代品和塑料替代品（英）

UNITEDNATIONSCONFERENCEONTRADEANDDEVELOPMENT

Technicalcooperationoutcome ADVANCECOPY

Leavingtheshore

Marine-basedsubstitutesandalternativestoplastics

Geneva,2025

?2025,UnitedNationsConferenceonTradeandDevelopment

Thefindings,interpretationsandconclusionsexpressedhereinarethoseoftheauthorsanddonotnecessarilyreflecttheviewsoftheUnitedNationsoritsofficialsorMemberStates.

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Thispublicationhasnotbeenformallyedited.

UNCTAD/TCS/DITC/INF/2025/4(advancecopy)

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Acknowledgements

ThisstudywaspreparedbytheDivisiononInternationalTradeandCommoditiesofUNTradeandDevelopment(UNCTAD),underthesupervisionandguidanceofChantalLineCarpentier,HeadoftheTrade,Environment,ClimateChangeandSustainableDevelopmentBranch.DavidVivas-EuguiandHenriquePaciniofUNCTADledthestudyteam.

UNCTADgratefullyacknowledgesthesubstantivecontributionsofLorenzoFormenti(UNCTADconsultant),KatnissXuejiaoLi(UNCTADvisitingresearcher)andMalickKane(UNCTAD)inthepreparationoftheoverallstudy.ThetechnicalinputsofRachidAmui(UNCTAD),ElisabettaErba(UniversitàdegliStudidiMilano),andPatriziaSilva(environmentalbiologist)inthewritingofchapter2;SaraFerro(sustainabilityexpert)andMariaDurleva(UNCTADconsultant)inthewritingofchapter3;MarcoFugazza,ChristianKnebel,LalenLleanderandSamuelMunyaneza(UNCTAD)inthewritingofchapter4arealsogratefullyacknowledged.

ThestudybenefitedfrominterviewswithBhimaAriesDiyanto(Reciki),AzzedineBadis(SeaweedCoalition),CindyParokkil(InternationalOrganizationforStandardization,ISO),CraigUpdyke(AmericanSocietyforTestingandMaterials,ASTM),JuliaReisser(Uluu),MalihaSumar(TheFlipFlopi/ThePeople&PlanetCompany),NurAhyani(WorldWildlifeFund-,WWF),XuesongLiu(Bottloop),SamanthaKiernan(YaleUniversity),MaheshSughatan(ForumonTrade,Environment,andtheSDGs),ShuntaYamaguchi(OrganisationforEconomicCo-operationandDevelopment,OECD).

ThisstudyresultsfromthecooperationbetweentheSustainableManufacturingandEnvironmentalPollution(SMEP)andOceanEconomyandFisheriesProgrammesofUNCTAD,withthesupportoftheForeign,CommonwealthandDevelopmentOffice(FCDO)oftheUnitedKingdomofGreatBritainandNorthernIrelandandtheGovernmentofPortugal.

DesktopformattingwasdonebyRafeDent(UNCTAD)andLiaTostes(UNCTADconsultant).

Abbreviations

ABS accessandbenefit-sharing

ASC AquacultureStewardshipCouncil

ASTM AmericanSocietyforTestingandMaterials

AVE ad-valoremequivalents

CAGR compoundannualgrowthrate

CITES ConventiononInternationalTradeinEndangeredSpeciesofWildFaunaandFlora

CSOs civilsocietyorganizations

FTA Freetradeagreement

GSC GlobalSeaweedCoalition

HS HarmonizedCommodityDescriptionandCodingSystem

ISA InternationalSeabedAuthority

KIIs keyinformantinterviews

LCA lifecycleassessment

MBSAs marine-basednon-plasticsubstitutesandalternatives

MEAs multilateralenvironmentalagreements

MFN mostfavourednation

MSC MarineStewardshipCouncil

NTMs non-tariffmeasures

P&C PrinciplesandCriteria(ofUNCTADBioTrade)

PE polyethylene

PHAs polyhydroxyalkanoates

PPMs processandproductionmethods

PS polystyrene

SIDS SmallIslandDevelopingStates

SMEP SustainableManufacturingandEnvironmentalPollutionProgramme

SPS sanitaryandphytosanitary(measures)

TBT technicalbarrierstotrade

TrPMs trade-relatedpolicymeasures

TüV Technischerüberwachungsverein(TechnicalInspectionAssociation)

VSS voluntarysustainabilitystandards

WCO WorldCustomsOrganization

WIPO WorldIntellectualPropertyOrganization

WTO WorldTradeOrganization

WWF WorldWildlifeFund

Tableofcontents

Executivesummary 1

ChapterI

Introduction 6

ChapterII

Marine-basednon-plasticsubstitutesandalternatives(MBSAs).9

Thepotentialofmarineresourcestoreplaceplastics 11

Afirstglobalmapping 13

ChapterIII

Challengesandopportunitiesforsustainablesocio-economic

development 15

Opportunitiesandenablingfactors 17

Seaweedandalgae 18

Marineminerals 20

Marineinvertebrates,plantsandwaste 22

Barrierstomarketdevelopment 22

Marketdynamics 23

Enablingtechnologyandinfrastructure 24

Socialandenvironmentalgovernance 27

EnvironmentalimpactthroughLCA 34

Theconventionalwisdomandlifecyclethinking 34

Keysubstitutiontradeoffs 35

ChapterIV

PursuingMBSAsthroughatradelens 39

4.1TheHarmonizedSystem(HS)asaframeworkformeasuring

tradeinMBSAs 41

TrendsandprospectsinglobalMBSAtrade 44

Globaltradetrends 44

MarketaccesspoliciesappliedtoMBSAs 48

ImporttariffsappliedtoMBSAs 48

Non-tariffmeasuresappliedtoMBSAs 50

ChapterV

Conclusionandthewayforward 56

References

62

Annex1 71

Annex2 72

Annex3 76

Annex4 78

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Executivesummary

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Executivesummary

Plasticpollutionthreatensmarineecosystems,humanhealth,andeconomicdevelopment.Theexcessiveuseofplastics,coupledwithinadequatewastemanagementsystems,hasledtotheaccumulationofplasticdebrisandplasticparticlesinoceans,posingriskstomarinelifeandcoastalcommunities.

Inresponsetothisgrowingcrisis,aUnitedNationsGlobalPlasticsTreatyisundernegotiations.UNCTADhasbeenconductingresearchandadvocatingfortherecognitionofnon-plasticsubstitutesandalternativesinthefuturetreaty.

Thisreportbuildsonpreviousresearchandexplorestheroleofmarine-basednon-plasticsubstitutesandalternatives(MBSAs).Thesealternatives,derivedfrommarineresourcessuchasseaweed,algae,andmarineminerals,offerpotentialtoreplaceconventionalplasticsinvariousapplications,therebyreducingplasticwasteandsupportingsustainabledevelopment.Unlikeconventionalplastics,MBSAsareofnaturalorigin,rangingfromalgae-basedpolymersforbioplasticstomineralcompounds

usedasfillersinglassandceramics.

Usingamixed-methodsapproachcombiningdeskresearch,originaldataanalysis,andkeyinformantinterviews(KIIs)(seeAnnex1),thisstudyinvestigatestheeconomicfeasibility,benefits,andtradeimplicationsofMBSAs,emphasizingtheirdualroleinmitigatingplasticpollutionandpromotingsocioeconomicdevelopment,particularlyincoastalregionsand

SmallIslandDevelopingStates(SIDS).ItalsoidentifiesanddiscusseskeychallengesrelatedtothedevelopmentofglobalMBSAindustriesinallthreedimensionsofsustainabledevelopment:economic,social,andenvironmental,assessingthematurityandoverallfitnessofenablingpolicyframeworks.

Inprinciple,marine-basedmaterialscanbeviablealternativestofossilfuel-basedplasticsduetotheirbiodegradability,goodfunctionality(e.g.,strength,flexibility)andrelativelylowenvironmentalfootprint.

Theirwidespreaduseinsupplychains,suchaspackaging,couldsignificantlyreduceplasticwasteanditsnegativeimpactonthemarineenvironment.Theglobalcommitmenttosustainabilityandthepotentialofmarinenaturalcapitaltosupporttransitionstoenvironmentallyfriendly,equitableandinclusiveproduction

systemsarealsoenablingMBSAs.However,well-documentedrisksassociatedwithmarineresourceexploitation–suchasthedepletionofhabitats,oceanacidification

andchemicalpollution,includingfromunregulatedorintrusiveseabedmining

–requirecarefulconsideration.

ByreviewingcasestudiesofsuccessfulMBSAimplementationworldwide,

thestudydemonstratesthatMBSAs,suchasalgae-basedbiopolymers,canreplaceconventionalplasticsinvariousofapplications,includingbutnotlimitedtopackagingandtextiles.Inthisview,thefurtherdevelopmentandmarketuptakeofMBSAscanalsoaddvaluetoupstreamoceanindustries,suchasseaweedfarming.Weassesspracticalviability

andmarketpotentialprovidingabasisforfurtherpolicyandanalyticalwork.

UNCTAD

advocatesfortherecognition

ofnon-plasticsubstitutesandalternativesinthefuture

GlobalPlasticsTreaty

GlobalMBSA

exportsreached$10.8billionin2022,growingthreetimesfasterthansynthetic

polymersoverthepast

decade

Thesocio-economicbenefitsofMBSAstypicallyincludejobcreation,economicdiversificationandimprovedlivelihoods,particularlyforyouthandwomen,aswellasfosteringindigenousinnovation,resiliencetoeconomicshocks,andfoodsecurity.Challengesinvolvetheneedfortechnologicalinnovationanddiffusion,sustainableharvestingpractices,and

marketaccess.Atpresent,highcostsandunfavourableeconomicshindermarketdevelopmentinseverallocations.Robustsupplychainsneedtobeestablished,withtargetedinvestmentsinresearchand

developmentandpublic-privatepartnershipstosupportthegrowthoftheMBSAsector.

SustainabilityisalsoakeydriverforthedevelopmentofMBSAindustries,requiringpolicyframeworksthatenablefairsupplychainrelationshipsandsoundnaturalresourcemanagement.Inthiscontext,lifecycleassessment(LCA)isimportanttoensurethattheenvironmentalbenefitsofMBSAs,suchasthelowcarbonfootprintinproduction,arenotoffsetbynegativeimpactsatotherstagesoftheirlifecycle.Thisisthecasewithmarinebioplastics,whichcanreleasegreenhousegases(GHGs)duringdecompositionintheabsenceofindustrialcompostingfacilities.

BilateraltradeflowdatashowthattheglobalmarketforMBSAsisgrowingwithsignificantpotentialforexpansion.Aftergrowingthreetimesfasterthansyntheticpolymersexportsbetween2012and2022,globalMBSAexportsreached

$10.8billionin2022.Theparticipationofcoastaldevelopingcountriesinthismarkethasalsoincreasedovertime,withsomebecomingtradingpowerhousesforcertainproducts(e.g.,Indonesiaforseaweed).

However,tariffsandnon-tariffmeasures(NTMs),includingenvironmental,healthandsafetyrequirements,hindermarketaccessforthesematerials,especiallyindevelopingcountries.Exceptformarineminerals,allMBSAsaresubjecttohighertariffsandmorestringentNTMsthanconventionalplastics.Sanitaryandphytosanitary(SPS)measureslinkedto

theirtradecanresultinhighcompliancecostsforcompanies.Thisisthecaseofseaweed,wherehealthrulesforedibleproductsalsoapplytonon-foodmaterialsusedinpackaging.ReducingtradebarriersandharmonizingrulescanenhancetheglobalcompetitivenessofMBSAs,suchasthroughmultilateraltradeandenvironmentalagreementsandstandard-settinginitiatives.

Inmovingforward,multi-stakeholderandinternationalcooperationisessentialtoaddressthesechallengesandfullyunlockthepotentialofMBSAs.Thesematerialsofferaviablestrategyfortacklingplasticpollutionwhilepromotingsustainableandinclusiveeconomic

developmentthroughtrade,especiallyfordevelopingcountries.Thepotentialrolesofstakeholdersinthisregardinclude:

Intergovernmentalorganisations(IGOs)andtheirmembers:considertheincorporationofanenablinginnovationandregulatorycontrolsmechanismforMBSAsandothernon-plasticsubstitutesundertheongoingUnitedNationsnegotiationsforaninternationallegallybindinginstrument(ILBI)onplasticpollution,includinginthemarineenvironment,creatingalevelplayingfieldwithplasticproducts.TheWorldCustomsOrganization(WCO)couldenhancetradeflowaccuracybyassigningdetailedcodesforMBSAs.AUnitedNationsTaskForceonseaweedcouldsupport

R&Dandregulatorydiscussions.

Governments:Establishsupportiveregulatoryframeworks,economicincentives,andpublic-privatepartnershipstoenableMBSAmarkets.Additionally,collaborateinR&DtoacceleratetheadoptionofMBSA.

Businesses:SupportsupplychainandmarketdevelopmentthroughR&Dinvestment,either

independentlyorinpartnershipwithgovernments;investinMBSA;adoptsustainablesourcingpractices,andadvocateforfavourablepolicies.

CivilSociety:Raiseawarenessthroughcampaignsandcommunityprojects,sensitizingstakeholdersandholdinggovernmentsandcompaniesaccountablefortheirsustainabilitycommitments.

Academia:EnhanceunderstandingoftherisksandopportunitiesassociatedwithMBSAsthroughcomprehensive,interdisciplinaryresearchandhelpdevelopmarket-readysolutionstoadvanceMBSAs.

Consumers:FostermarketgrowthanddriveadoptionofMBSAsbymitigatingcostbarriersandcultivatingenvironmentalawarenessandawillingnesstopayforsustainable

blueeconomyalternatives.

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ChapterI

Introduction

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Introduction

Plasticshavebecomeafundamentalenablerofhumaneconomicactivityasitisinextricablywovenintothefabricoftheglobaleconomyandtrade.Theirlowcostandunparalleledversatilityhavedriventheirwidespreadadoptionacrossallsectors,fromconsumergoodstoindustrialapplications,leadingtheworldtobeundeniablyplastic-dependent.Tradeinplasticsatalllevelsofthevaluechainalreadyreachedarecord$1.2trillionin2022(UNCTAD,2023a).Projectionsdonotshowadifferentoutlook.Withoutdecisivepolicyinterventions,plasticuseisonatrajectorytotripleby2060,withthelargestincreasesexpectedindevelopingregionssuchasSub-SaharanAfricaandAsia(OECD,2022).

Whileplasticshavebeeninstrumentaltoeconomicgrowth,theyhavealsoemergedasanunprecedentedthreatto

theenvironmentandhumanhealthduetotheirpersistentnature.Intheabsenceofcertainconditions,plasticswastecantakebetween20toover500yearstobreakdownanddegradeintheenvironment,dependingonthechemicalcompositionandtheproduct(UnitedNations,2021).

Ineffectivewastemanagementacrosstheglobehasexacerbatedthiscrisis,leadingtoapervasivepollutionproblem.Frommunicipalsolidwastetomicroplasticspollutingtheocean,theenvironmentalandhealthconsequencesareprofound.Despiteglobalefforts,plasticwasteisexpectedtopermeateecosystemsfor

decadestocome(Winnie,Lauetal.,2020).

Thealarmingglobalissueofplasticspollutionhascreateda“pressingcase”fornaturalandenvironmentallyfriendlysubstitutesandalternativestoplastics(UNCTAD,2023a).Whilephasingoutplasticsentirelymaynotbefeasibleintheshortterm,developingandadoptingalternativematerialscouldplayacrucialroleincurbingplasticwaste.Inthisviewthatcountriesarebeingencouragedto

transitiontowardsanewplasticseconomythatreducepollutingplasticuseandprioritizes,wherepossible,sustainableandsafesubstituteswithcomparablefunctionalproperties.Traditionalmaterials,suchas

paperandglass,offerestablishedandreadilyavailableoptionsforreducingourrelianceonplastics.Innovativeapproacheshavescaledwheresubstitutessuchaspaperandglassworkalongsideplastics

tocreatesustainableproducts.Forinstance,flexiblepackaging,combinespaperandplasticfilmofferingtoprovidefunctionality(e.g.,moistureinsulation)thatiscomparabletothatofplastic-basedsolutions.Atthesametime,lesscommonfibre-basedmaterials,suchasbagasseandbamboo,aregainingtractionasarenewableandbiodegradablealternativesforsingle-useplasticproducts(e.g.,cups,straws),promotingacirculareconomy

byaddingvaluetoexcessbiomass.

Whiletheirscalabilityisstilluncertain,theirpotentialisbeingexploredbymaterialsscientistsandsustainabilityexperts,pavingthewayfornewbusinessmodelsthatcombinevalueadditionandresourceefficiency.UNCTADresearchshowsthatnon-plasticsubstitutesandalternativesareattractingmoreregulatoryinterest

asbusinessesincreasinglyrecognizethebenefitsofsustainability.Indeed,sustainabletradecannotonlysupportthediffusionoflowcarbonmaterialsand

technologiesbutalsocontributetosocio-economicdevelopmentinproducingcountries.However,tofullyrealizethispotential,investmentmustberedirectedfromfossilfuel-basedplasticproduction

towardsnewbusinessmodelscentredonsubstitutematerials(ThePewCharitableTrustsandSYSTEMIQ,2020).

Marineandcoastalecosystemsareincreasinglyrecognizedaspivotalforthesustainabledevelopmentofcoastalregions,particularlySIDS.Theiruniquenaturalcapitalprovidesaprimeopportunitytofosternewentrepreneurialecosystemsthatcanbalanceeconomicgrowthwithenvironmentalprotection,throughtrade.Ecosystems,

suchasfarming,processingandmarketingofalgalproducts,offerpotentialaccess

tonaturalresources(e.g.,water,minerals)withreducedcompetitionandlandusepressures.However,challengessuch

astheconservationofbiodiversityandmarinehabitatsmustbecarefullymanagedthrougheffectivepolicyframeworksto

fullyrealizethepotentialbenefits.

Thisstudypresentsoriginalresearchdemonstratingthepotentialfortradeinmarine-basednon-plasticsubstitutesandalternatives(MBSAs)toaddressplasticpollution,whilepromotingsustainableeconomicdevelopmentincoastalcommunities,includinginSIDS.Bylookingatselectedocean-basedsupplychainsandunconventionalusesoftheirproductsandbyproducts,suchastheproduction

ofbioplasticpolymersfromalgae,itrespondstothreespecificobjectives:

IdentifypromisingMBSAs,definedasnaturalresources,bio-basedmaterialsandcomponentsthathavearoleorpotentialinreplacingfossilfuel-basedplastics,eitherdirectly,asbuildingblocksoradditivesforalternativebioplastics,orindirectly,asinputstoproducenon-plasticsubstitutes(e.g.,ceramics,glass).

Analysethepotentialfortrade-ledsocio-economicdevelopmentofMBSAsinproducingcountriesvis-à-visenvironmentalandsocialrisks.

Accordingly,discussthemaintrade-offsbetweenenvironmentalsustainabilityandeconomicfeasibilityassessedthroughLCAconsiderations.

Discusspolicyframeworksthatcanincentivizetradeinmarine-basednon-plasticsubstitutesand

alternatives,includinge.g.,tariffandnon-tariffmeasures,andstandards.ThisisintendedtoinformtheupcomingroundsofnegotiationsofaUnitedNationsGlobalPlasticsTreaty,withaviewtosupporttrade-relatedpolicycoherenceandharmonization.

Chapter1providescontextandintroducestheoverallpurposeandobjectivesofthestudy,includinganoverviewofmarinebiomaterialsandtheirdownstreamuses.Chapter2highlightstheirpotentialforsustainabletradeandpresentsanovelmappingofMBSAscoveringmarineresourcesandtheirimmediatederivatives.

Chapters3and4examinethemicro-economicsandlocalimpactsofglobalMBSAtrade.Chapter3discussesthemainchallengesandopportunitiesforsocio-economicdevelopmentaffectingMBSAindustries.OpportunitiesareanalysedforkeyMBSAsupplychains,suchasseaweedandalgae,whilethreemaintypesofbarrierstothedevelopmentoftheseindustries

areconsidered:marketdynamics(e.g.,economiesofscale),enablingtechnologiesandinfrastructure,andsustainability.

Thechapteralsomapsoutthemainenvironmentalimpactsoriginatingfromtheproduction,marketing,consumptionanddisposalofMBSAsanduseslifecycle

thinkingtodiscussthemaintrade-offsinthesubstitutionformoresustainablematerials.

Fromatradeperspective,Chapter4estimatesthesizeoftheglobalMBSAmarketusingbilateraltradeflowdataasaproxyfordemand.Theaverageappliedtariffsandnon-tariffmeasures(NTMs)

affectingthesematerialsarealsoanalysedtoprofilethetradedistortionsandmarketaccessconditionsprevailinginMBSAmarkets.Chapter5concludesandprovidesanarrativeonthewayforward.

Plasticwastecantakebetween

20toover

500yearstodegradeintheenvironment

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ChapterII

Marine-basednon-plastic

substitutesandalternatives

(MBSAs)

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Marine-basednon-plasticsubstitutesandalternatives(MBSAs)

Theocean

offersunderexploredopportunitiestocurbplasticwastethroughmarine-basedsubstitutes

Thepotentialofmarineresourcestoreplaceplastics

Throughitsuniquemixofnaturalcapital,theoceanhasshapedthecourseofhumanhistoryanddeterminedthekeytrajectoriesofcivilization.Fromensuringsustainablelivelihoodsthroughfisheriestofacilitatingtraderoutes,humanityhaslongreliedonoceanstomeetitsmostpressingeconomicandsocialneeds(Allisonet

al.2023).Astheworldisconfrontedwiththeneedtotransitiontomoreequitableandsustainableproductionsystems,

theoceancontinuestoprovideaccesstoinvaluableresourcesandecosystem

services,suchascarbonsequestrationandbiodiversityconservation,withincreasinginterestfromgovernmentsinpromoting

itforthedevelopmentoftheirnationaleconomies(Martínez-Vázquez,Milán-GarcíaanddePabloValenciano,2021).

However,theoceanisnotimmunetothenegativeenvironmentalexternalitiesofhumanactivityandthechallenges

ofachangingclimate(IPCC,2019andIOC-UNESCO,2022).Duetothenon-biodegradablenatureofconventionalplastics,plasticpollutionhasbecomeasignificantthreattomarineecosystemsandcoastalcommunities.1

Theveryenvironmentthreatenedbyplasticsmightofferpreviouslyunderexploredopportunitiestocurbplasticwaste

andholdthekeytoamoresustainablefuture.Infact,manyofthebio-basedcomponentsthatcanreplacefossilfuel-basedplastics,suchasinfoodpackaging,haveastrongmarineconnectionandcanbesourcedfromthemarineandcoastalenvironment(Ayyakkalaietal.,2024;Pipunietal.,2023;Boseet.Al,2023).

MBSAsencompasstheentiremateriallifecycle,fromrawmaterialextractiontoend-of-life.Theyrangefromlivingorganismsfoundinmarineandcoastalecosystemsthatcanbeusedasfeedstock(e.g.,seaweed)toby-productsofaquacultureorseafoodprocessingassourcesof

biologicalcompounds(e.g.,molluscshells).

Thepotentialapplicationsforreplacingplasticsarediverseandvaryaccordingtotheirdegreeofconversion(Table

Forinstance,microalgaeandothermicroorganismsshowstrongpotentialasasourceofbiopolymers,suchaspolyhydroxyalkanoates(PHAs),whicharedirectlyusedasbuildingblocksforbioplastics.2Conversely,inorganic

compoundssuchasmineralscanindirectlysupportthesubstitutionofplasticsasinputstoproducenon-plasticsubstitutes.Forexample,highpuritysilicasandshavewideapplicationsintheproductionofglass.

Contrarytopopularbelief,biodegradableplasticsarenotapanaceaforplasticpollution.Theyonlydegradeunderspecificconditionsandtheirrateofdegradationinthenaturalenvironmentcanvarysignificantlydependingonhowwelltheseconditionsaremet.Influencingfactorsincludethetypeofbioplastics,environmentalconditions(e.g.,temperature,humidity,availabilityofoxygen)andthepresenceofmicroorganismsthataffectdegradation.Whilebiodegradableplasticscandegradeintheocean,theymaytakealongtimetodegradeormaynotbreakdowncompletelyintoharmlesssubstancesduetofactorssuchassalinityandpollutants.Theseconsiderationsalsoapplytomarine-basedbioplastics.

Technically,polymersarelargemoleculesformedbylinkingnumeroussmallermolecules,calledmonomers,throughcovalentchemicalbonds.Thesemonomersactasrepeatingunits,creatingalongchain-likestructure.Thespecificpropertiesofapolymer(strength,flexibility,etc.)aredeterminedbythetypeofmonomerused,thelengthofthechain,andthearrangementofthemonomerswithinthechain.Theseuniquepropertiesallowpolymerstobethefundamentalbuildingblocksofplastics.Byvaryingthemonomerandchainstructure,avastarrayofplasticscanbeproducedwithawiderangeofcharacteristicsforcountlessapplications.

Table1

Potentialapplicationsofbio-basedcomponentsofmarineoriginforthereplacementofplastics

Lifecycle

stage Category Examples Potentialapplications

Rawmaterials

Macroalgae(seaweed)

Kelp,Wakame,Carrageenanmoss

Bioplastics,gelsforcosmeticsandpharmaceuticals,foodthickeningagents,wastewaterreuse

Microalgaeandothermicroorganisms

Microalgae,bacteria,diatoms

Bioplastics,biofuels,biodegradabledetergents

Minerals,fromtheseabedorcontinentalshelf

Marineclays,silicasandsandquartz,calcite

Fillersinbiocomposites,ceramics,glass

Marineinvertebrates

Sponge

Filtrationandabsorptionmaterials(e.g.,forwaterpurification)

Processing

Biopolymers

Polyhydroxyalkanoates(PHAs),carrageenan

Biodegradablefilms,coatings,fibres

Bioplasticfilms,foilandsheets

Seaweed-basedorPHA-basedfilms

Foodpackaging,carrierbags,agriculturalfilms

Gels,foamsandcreams

Agar-agar

Thickeningorgellingagents,emulsifiers

Naturalfibre

Seaweed-basedyarn,mangrove-basedplaitingmaterial

Textiles,basketwork

Biofuels

Algae-basedbiodiesel,ethanol

Transportationfuels

Manufacturing

Paper

Algae-basedpulpandpaper

Packagingmaterials,printingpaper

Glassandglassware

Glass,madefromsilicasandandquartz

Foodpackaging,construction

Othermanufactures

Chitin-basedfishingnets,seagrassbasketry

Miscellaneous

End-of-life

Fishwaste,forpurposesotherthanfood,feedorfertilizer

Molluscshells,fishscales(e.g.,forextractingChitin)

Fillersinbiocomposites,bioplastics

Source:UNCTADanalysisbasedonAyyakkalaietal.(2024),UNDP(2024),UnitedStatesGeologicalSurvey(2024),Boseetal.(2023),Jianxin,F.etal.(2023),Pip