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Vitamin A is a vital fat-soluble micronutrient essential for vision, immune function, and skin health, yet its therapeutic potential is frequently limited by poor aqueous solubility, chemical instability, and low oral bioavailability. Traditional delivery methods often fail to protect this sensitive retinoid from oxidative degradation and first-pass metabolism. This review explores the emergence of liposomal encapsulation as a transformative strategy to overcome these barriers. By embedding Vitamin A within phospholipid bilayers, liposomes enhance its stability, shield it from harsh gastrointestinal conditions, and facilitate superior absorption through biomimetic membrane interaction and lymphatic transport pathways. The article examines the formulation chemistry, manufacturing technologies—such as high-pressure homog- enization and critical characterization parameters including particle size, zeta potential, and encapsulation efficiency. Furthermore, it highlights the clinical implications of targeted delivery in both nutrition and der- matology, where liposomal systems provide a controlled-release mechanism that reduces systemic toxicity and local irritation. A specific focus is placed on industrial advancements such as LipoedgeTM technology, which demonstrates a significant 2.36-fold increase in bioavailability. This review concludes that liposo- mal Vitamin A represents a superior alternative to conventional formulations, offering a precision-based approach to nutrient delivery and therapeutic skin care.
Keywords: Vitamin A; immune function; oxidative degradation; first-pass metabolism; phospholipid bilayers; liposomes; VitaminA; immunefunction; oxidativedegradation; first-passmetabolism; phospholipidbilayers
VitaminA,anessentialfat-solublemicronutrient,isvitalforseveralphysiologicalprocesses,includingthe maintenanceofhealthyvision,immunesystemregulation,andcellulardifferentiation[1,2]. Asapowerful antioxidant,itplaysakeyroleinepithelialtissuerepairandisacornerstoneindermatologicaltreatments duetoitsregenerativeproperties[3]. Despiteitsimportance,VitaminAishighlysusceptibletochemical instability,frequentlydegradingwhenexposedtolight, heat,oroxygen[1].Furthermore,itslipophilicnature andsusceptibilitytofirst-passmetabolismoftenleads topoorgastrointestinalabsorptionandinconsistent bioavailabilityintraditionaloraldeliveryforms[2]. Liposomal encapsulation has emerged as a sophisticateddeliverystrategytoovercomethesephysicochemicalbarriers.Liposomesaremicroscopicvesicles composedofphospholipidbilayersthatcaneffectively encapsulateandshieldsensitivecompoundslikeVitaminAfromenvironmentalstressorsandharshgastricconditions[4].Bymimickingbiologicalcellmembranes,thesenanocarriersfacilitateimprovedsolubilityandcontrolledreleaseofthenutrient[5].ThistechnologicalapproachsignificantlyenhancesthetransportofVitaminAacrosscellularbarriers,therebyincreasingitsoverallsystemicabsorptionandtherapeuticefficacycomparedtonon-encapsulatedforms[4, 5].
ThisreviewarticlewillprovideanexhaustiveexaminationofliposomalVitaminA,focusingonitsformulationchemistryandthemechanismsdrivingitsenhancedbioavailability.Thesubsequentsectionswill discussvariousclinicalimplicationsoftargeteddeliveryinbothnutritionanddermatology.Finally,thearticlewillevaluaterecentmarketinnovations,suchasthe Lipoedge™technologybyWestBengalChemicalIndustriesLtd.,Kolkata,India(WBCIL).Lipoedge™represents aproprietaryadvancementdesignedtoproducehighly stable,nanometricvesicleswithsuperiorencapsulationefficiency—reportedlyreachingover70%ensuring optimaluniformdistributionandcellularpenetration withouttheriskofparticleaggregation[6].
The formulation chemistry of liposomal Vitamin A is centred on the strategic assembly of amphiphilic phospholipidstocreateaprotective,biomimeticenvironmentforthehydrophobicretinoidmolecule.At themolecularlevel,phospholipids—mostcommonly phosphatidylcholinederivedfromsoyorsunflower— spontaneously organize into closed bilayer vesicles whendispersedinanaqueousmedium[4,7].Because VitaminAishighlylipophilic,itdoesnotresideinthe aqueouscoreoftheliposome;instead,itispartitioned
intothehydrophobic“tail”regionofthelipidbilayer[1, 8].Thisspatialarrangementiscriticalforstability,as thesurroundingphospholipidheadsactasachemical shieldagainstexternaloxidativestressorsandUVlight [4].
Tooptimizetheseformulations,researchersoftenmanipulatethelipidcomposition,suchasbyincorporating cholesterol to modulate membrane fluidity and rigidity [7]. High-purity phospholipids with specific fattyacidchainlengthsareselectedtoensuremaximumencapsulationefficiencyandtopreventthe“leakage” of Vitamin A from the bilayer [8, 9]. Advanced formulationtechniques,includinghigh-pressurehomogenizationandthin-filmhydrationfollowedbyextrusion,areutilizedtoachieveananometricparticle size,typicallyrangingfrom50to150nm. Thissmall sizeissuitabletocrossblood-brainbarrier[5,6].This precise control over particle size and zeta potential (surfacecharge)isessentialformaintainingcolloidal stability,preventingthevesiclesfromaggregatingor sedimentingovertime[6,7].
TheenhancedbioavailabilityofliposomalVitaminAis drivenbyseveraldistinctphysiologicalandbiochemicalmechanismsthatbypassthelimitationsofconventionaldelivery.Primarily,theliposomeactsasa“TrojanHorse,”shieldingVitaminAfromtheharsh,acidic environmentofthestomachandthedegradativeenzymesinthesmallintestine[2, 10]. Thisprotection ensuresthatahigherpercentageoftheintactnutrient reachestheprimarysitesofabsorption[4].Onceinthe intestine,thebiomimeticnatureofthephospholipid bilayerallowstheliposometointeractdirectlywith theenterocytemembranesthroughpathwayssuchas endocytosisordirectmembranefusion[10,11]. Furthermore,liposomaldeliveryfacilitatesaunique absorptionrouteviathelymphaticsystem.Whileconventionalfat-solublevitaminsoftenrelyontheslow processofmicellarsolubilizationandbiliarysecretion, nanometricliposomescanbeabsorbeddirectlyinto thelacteals—thelymphaticcapillariesofthesmall
Bone-Targeted Deliv- Developed Vitamin A liposomes that selectively target Sachaniya et al. ery bonetissue;observedincreasedosteoblastactivitywith- (2018)[13] outsystemictoxicity.
ComparativeBioavail- Demonstrated that nano-delivery systems significantly Taha et al. (2007) ability increaseCmaxandAUCcomparedtotraditionaloilyVita- [15] minAsolutions.
NutricosmeticApplica- ConfirmedthatliposomalencapsulationenhancesVita- Adamantidi et al. tion minApenetrationintodermallayers,boostingcollagen (2025)[3] synthesis.
Food/NutritionStabil- Reportedthatencapsulationprovidesachemical“shield” Akrametal.(2023) ity againstUVlightandoxidation,maintainingpotencydur- [4] ingstorage.
Pharmacokinetics Highlightedtheroleofnanocarriersinbypassingfirst-pass Carazoetal.(2021) metabolismviathelymphaticabsorptionpathway. [1]
intestine[10,12].ThislymphaticuptakeallowsVitamin Atoenterthesystemiccirculationwhilebypassingfirstpassmetabolismintheliver,leadingtosignificantly higherpeakplasmaconcentrations(Cmax)andgreater overallsystemicexposureasmeasuredbytheAreaUndertheCurve(AUC)[10]. Additionally,thesimilarity betweentheliposomalbilayerandhumancellmembranespromotesmoreefficientintracellulardelivery, ensuringthattheVitaminAisnotjustcirculatinginthe bloodbutiseffectivelyinternalizedbytargettissues [4,11].
Theclinicalapplicationoftargetedliposomaldelivery representsaparadigmshiftinaddressingnutritional deficienciesandchronichealthconditions.ByensuringthatVitaminAisdelivereddirectlytospecifictissuesorsystemiccirculationwithhighprecision,liposomalsystemsmitigatetherisksassociatedwithtraditionalhigh-dosesupplementation,suchasgastric irritationandnon-specifictoxicity[1,4].Inclinicalsettings,theabilitytoachievetherapeuticplasmalevels withloweroraldosesreducesthemetabolicburden ontheliverandkidneys,acriticalfactorforpatients withcompromisedorganfunctionormalabsorption syndromeslikeCeliacdiseaseandCrohn’sdisease[1, 10].
Oneofthemostsignificantclinicalimplicationsisthe potential for bone-targeted therapy. Research has demonstratedthatVitaminA-encapsulatedliposomes canbeengineeredtodeliverthenutrientselectivelyto bonetissues,offeringanovelapproachtomanaging conditionslikeosteoporosis[13].Whileexcessivefree VitaminAisoftenlinkedtocompromisedbonemineraldensity,thecontrolled-releasenatureofliposomal formulationsensuresthatthenutrientpromotesosteoblastproliferationwithoutreachingtoxicsystemic concentrations[13,14]. Thistissue-specificdelivery effectivelybypassesthetransportlimitsimposedby Transthyretin(TTR),theprimarycarrierproteinforVitaminAintheblood,whichoftenrestrictsnutrientuptake inskeletaltissues[13].
Furthermore,theclinicalefficacyofliposomalVitamin A is characterized by superior pharmacokinetic profilescomparedtoconventionaloilysolutions. Clinicalevaluationsofsimilarliposomaltechnologieshave shownuptoa2.36-foldincreaseinrelativebioavailability,withsignificantlyhigherpeakplasmaconcentrations(Cmax)andextendedsystemicexposure(AUC)[6, 15].Forclinicians,thistranslatestomorepredictable patientoutcomesandfastercorrectionofsubclinical deficiencies.Additionally,inthefieldofnutricosmetics,thetargeteddeliveryofVitaminAtodermallayers throughliposomalsystemshasshownenhancedefficacyinstimulatingcollagensynthesisandreducing oxidativeskindamage,providingaclinical-gradesolutionforanti-agingandskinhealth[3,11].
Indermatology,theclinicalapplicationofliposomal VitaminA—primarilyintheformofretinolorretinyl palmitate—addresses the historical “gold standard” paradox:whileretinoidsarepeerlessintreatingphotoaging and acne, their use is frequently limited by retinoiddermatitis,characterizedbyredness,scaling, andburning[3,16]. Liposomaldeliverysystemssignificantlymitigatethesesideeffectsbycontrollingthe
Retinol Skin Rejuvena- Demonstrateddeepfollicularpenetrationandasig- Kim&Baeg(2024) tion nificantincreaseinTypeIcollagensynthesiswith [17]
Retinyl Palmi- IrritationMitiga- Confirmedthatliposomalencapsulationreduces Rahman et al. tate tion “retinoiddermatitis”(erythemaandscaling)bypro- (2023)[16]
Retinoids Photoprotection IdentifiedthatlipidbilayersshieldVitaminAfrom Adamantidi et al.
Retinol Barrier Func- Reported that phospholipid-based vesicles inte- Al-Hajaj et al. tion gratewiththestratumcorneum,reducingtransepi- (2025)[9]
Retinoid Com- Target Effi- Clinicalobservationsshoweda40%improvement LipsoBio Study plex ciency in fine line reduction due to the superior dermal (2024)[11]
releaserateoftheactiveingredient.Insteadofanimmediate“bolus”deliverythatoverwhelmstheepidermis,liposomesprovideasustainedrelease,maintainingtherapeuticlevelswithintheskinwhileminimizing theirritationtypicallyassociatedwithfreeretinoids [11,16].
Thetargetednatureofthesenanocarriersallowsfor enhancedpenetrationthroughthestratumcorneum, theskin’sprimarybarrier.Becausethelipidbilayerof theliposomeisstructurallysimilartotheintercellular lipidsoftheskin, itcan“fuse”withtheskinsurface ortraversethefollicularpathway[9,17].Thisensures thatVitaminAreachesthedeeperepidermalanddermallayerswherefibroblastsreside. Oncedelivered tothesetargetsites,VitaminAstimulatestheexpressionofTypeIcollagenandinhibitsmatrixmetalloproteinases(MMPs),theenzymesresponsibleforcollagen degradation[3,17].Clinically,thisresultsinameasurablereductioninfinelines,improvedskinelasticity, andmoreuniformpigmentation[3].
Furthermore,liposomalencapsulationprovidesavital clinicaladvantageregardingphotostability. ConventionalVitaminAisnotoriousfordegradingrapidlyupon exposuretoUVlight,whichnotonlyrenderstheproductineffectivebutcanalsoleadtotheformationof phototoxicbyproducts[1,17].ByshieldingtheVitamin Amoleculewithinaphospholipidmatrix,liposomal formulationsmaintaintheirpotencyevenunderlight exposure,ensuringthatthepatientreceivesthefull therapeuticdoseduringdaytimeapplication[16].This stability,combinedwiththereducedriskoftransepidermalwaterloss(TEWL),positionsliposomalVitamin Aasasuperiorclinicaloptionforpatientswithsensitive reducedepidermalthinning.
vidingaslow,controlledreleaseoftheactive.
UV-induceddegradation,preventingtheformation (2025)[3] ofphototoxicbyproductsduringdaytimewear.
dermalwaterloss(TEWL)comparedtofreeretinol.
bioavailabilityofnanometricvesicles.
skinorchronicdermatologicalconditions[9,11].
TheLipoedge™technology,developedbyWBCIL,representsastate-of-the-artadvancementinthefieldof nutritionalnanotechnology.Thisproprietaryplatform isspecificallyengineeredtoaddresstheinherentchallengesofdeliveringunstable,fat-solublemicronutrients like Vitamin A [6]. By utilizing a high-precision particleengineeringprocess, Lipoedge™transforms standardactiveingredientsintonanometricliposomal vesiclesthatexhibitsuperiorcolloidalstabilityandbiologicalperformance[6,18]. ThecoreofLipoedge™ technologyliesinitsabilitytoachieveexceptionally highencapsulationefficiency,oftenexceeding >70% forlipophiliccompounds[6].Thisensuresthatnearly the entire payload of Vitamin A is securely trapped withinthephospholipidbilayer,minimizingwasteand maximizingpotency.Keytechnicaladvantagesinclude nanometricparticlesize,enhancedstability,andpredictablepharmacokinetics.Thetechnologyproduces vesiclestypicallyrangingbetween50and150nmideal tocrosstheBBbarrier[6].Thisultra-smallsizeiscriticalforbypassingthebody’snaturalfiltrationsystems andenhancingtransportacrosstheintestinalanddermal barriers. Lipoedge™ formulations are designed toresist“leakage”andaggregation.ThestructuralintegrityofthevesiclesprotectsVitaminAfromoxidation andphotodegradation,extendingtheshelf-lifeofthe finalproduct[6,18].Clinicaldataassociatedwiththis technologyindicatesasignificantimprovementinnutrientabsorption.Incomparativestudies,Lipoedge™baseddeliverysystemshavedemonstrateda2.36-fold increaseinrelativebioavailabilitycomparedtoconventionalnon-encapsulatedforms[6].Fromaclinicalperspective,Lipoedge™allowsformoreprecisedosing,as thehighabsorptionrateensuresthatloweroralortopicaldosescanachievethedesiredtherapeuticeffect[6, 10].ThisisparticularlybeneficialforVitaminA,where excessivesystemicconcentrationscanleadtotoxicity, buttargeteddeliveryensuresthenutrientreachesthe cellswhereitismostneeded. Forthepharmaceuticalandnutricosmeticindustries,WBCIL’stechnology providesarobustsolutionfordevelopinghigh-efficacy productsthatmeetthegrowingconsumerdemandfor advanced,science-backeddeliverysystems[18].
TheindustrialproductionofliposomalVitaminArequiresspecializedtechniquestoensureuniformparticlesizeandlong-termstability.Traditionalmethods, suchasthin-filmhydration,areeffectiveforsmall-scale laboratoryresearchbutareoftenreplacedincommercialsettingsbyhigh-throughputtechnologieslikehighpressurehomogenization(HPH)andmicrofluidization [4,19]. Thesemethodsapplyintenseshearforcesto reduce large multilamellar vesicles into small, unilamellar vesicles with a narrow polydispersity index [19]. ForVitaminAspecifically,manufacturingmust beconductedunderinertgas(suchasnitrogen)and controlledlightingtopreventthedegradationofthe light-sensitiveretinoidduringtheemulsificationprocess[1,20].
Oncemanufactured,theliposomesmustundergorig-
orouscharacterizationtoverifytheirqualityandperformance.Theprimaryparametersevaluatedinclude ParticleSizeandpolydispersityindexmeasuredviaDynamicLightScattering(DLS),ensuringthevesiclesfall withintheideal50–150nmrangeforoptimalbioavailability [5, 6]. Zeta Potential measures the surface chargeoftheliposome;ahighabsolutezetapotential (typically > ±30mV)indicatesstrongelectrostaticrepulsion,whichpreventstheparticlesfromclumpingor aggregatingovertime[7,20].DLS,alsoknownasphotoncorrelationspectroscopy,istheprimarymethod usedtodeterminetheMeanHydrodynamicDiameter of liposomes [19]. When laser light hits the moving vesiclesinaliquidsuspension,thelightscatters;the speedofthesefluctuations(Brownianmotion)allows thesoftwaretocalculatethesizeoftheparticles[20]. ForaformulationlikeLipoedge™,maintainingasize between50–150nmisvital[6].Iftheparticlesaretoo large,theymaybeclearedbythereticuloendothelial system(thebody’s“filter”)beforetheycandeliverVitaminAtothetargettissues[21]. Furthermore, the polydispersityindexiscalculatedtomeasuretheuniformityofthesample. APDIvalueoflessthan0.2is generallysoughtinpharmaceutical-gradeliposomes, indicatinga“monodisperse”populationwhereallvesicles are roughly the same size, ensuring consistent dosingandabsorptionrates[20,22].TheZetaPotentialmeasurestheelectrokineticpotentialor“surface charge”oftheliposomesinasuspension[7].Thisisa keyindicatoroftheformulation’sphysicalstability.If theliposomeshaveahighpositiveornegativecharge (typicallygreaterthan ±30mV),theywillrepeleach other,preventingthevesiclesfromclumpingtogether or“aggregating”duringstorage[22].InthecaseofVitaminA,whichispronetodegradationifthebilayer breaksdown,astableZetaPotentialensuresthatthe “protectiveshield”remainsintact[4].LowZetaPotentialvaluesoftenleadto“flocculation,”wheretheliposomesmergeintolargerclusters,drasticallyreducing theirabilitytopenetratetheskinorintestinallining [20,22].EncapsulationEfficiencyisdeterminedbyseparatingthe“free”VitaminAfromtheencapsulatedportionusingultracentrifugationordialysis,ensuringthat technologieslikeLipoedge™maintaintheirhighpayloadstandards[6,18]. Morphologyvisualizedusing TransmissionElectronMicroscopy(TEM)orCryo-SEM confirmsthespherical,closed-bilayerstructureofthe vesicles[19,21]. Cryo-TEMisusedtoprovidevisual proofoftheliposome’sarchitecture.Unlikestandard TEM,whichcandehydrateanddamagedelicatelipid bilayers,Cryo-TEMfreezesthesampleinstantlyinits naturalaqueousstate[19,21].Thisallowsresearchers to confirm that the Vitamin A has been successfully incorporatedintoaunilamellar(single-layer)vesicle ratherthanalessefficientmultilamellar(multi-layer) structure[21].Thisvisualverificationisthe“goldstandard”forconfirmingthatthemanufacturingprocess hassuccessfullycreatedtheintendednanostructure [22].
TheclinicalsafetyprofileofVitaminAissignificantly altered by liposomal encapsulation. While conventionalVitaminA(retinol)isassociatedwithpotential toxicity—specifically hypervitaminosis A, which can leadtoliverstressandbonedensityissues—liposomal systemsofferacontrolled-releasemechanismthatreducestheriskofsuddenplasmaspikes[1,23].Bypartitioningthevitaminwithinalipidbilayer,thedelivery systemensuresagradualrelease,whichminimizesthe metabolicstrain onthe liver andreduces theoccurrenceofgastrointestinaldistressoftenreportedwith high-dosetraditionalsupplements[10,23]. Because liposomaltechnology,suchasLipoedge™,enhances bioavailabilitybyapproximately2.36times,thestandardoraldosecanoftenbereducedwhilemaintainingthesametherapeuticeffect[6]. Forgeneraldeficiencyprevention,dosestypicallyalignwiththeRecommendedDietaryAllowance(RDA)of700–900µgof RetinolActivityEquivalents(RAE)foradults[1,23].In clinicalcasesofseveredeficiencyortargeteddermatologicaltreatment,higherdosesmaybeprescribed; however,theincreasedabsorptionefficiencyofliposomesmeansthataliposomaldoseof1,500µgmay providesystemicexposureequivalenttomuchhigher dosesofconventionaloilysolutions[15,23].
The Tolerable Upper Intake Level (UL) for Vitamin A isestablishedat3,000µgRAE/daytopreventteratogeniceffectsandliverdamage[1].Liposomalformulationsmustbemonitoredcloselyinpregnantpopulationsduetothishighabsorptionefficiency.Furthermore,thesurfactantsandphospholipidsusedinthe formulation—suchasphosphatidylcholine—aregenerallyrecognizedassafe(GRAS)byregulatorybodies liketheFDA(Food&DrugAdministration),furthersupportingthesafetyofthedeliveryvehicleitself[20,24]. Regardingdermatologicalconditions,topicalsafetyof liposomalVitaminAisdefinedbyitsabilitytobypass the“retinoidreaction.”Clinicalstudiesshowthatliposomalretinolsignificantlyreducestheexpressionof inflammatorycytokinesintheskincomparedtofree retinol,allowingpatientswithsensitiveskintotoleratetherapeuticconcentrationsthatwouldotherwise causeseverepeelingorerythema[16,17].
LiposomalVitaminArepresentsasignificanttechnologicalleapinthefieldofnutritionalscienceandclinicaldermatology.Byleveragingadvancedlipid-based nanocarriers,thisdeliverysystemeffectivelyresolves thelong-standingchallengesassociatedwiththechemicalinstabilityandpoorbioavailabilityoftraditional retinoids.TheencapsulationofVitaminAwithinphospholipidbilayersprovidesarobustshieldagainstenvironmentaldegradationwhilefacilitatingasophisticated“TrojanHorse”mechanismforabsorption.This resultsinenhancedtransportthroughtheintestinal lymphaticsystemanddeeperpenetrationintothedermallayersoftheskin,ultimatelyensuringthatthenutrientreachesitstargetsiteswithhigherprecisionand efficacy.
The clinical implications of this technology are profound.Innutrition,liposomalsystemsallowformore predictablepharmacokineticoutcomesandthepotentialforlower,saferdosingstrategiestotreatdeficiencies.Indermatology,thecontrolled-releasenatureof thesevesiclessignificantlyreducestheriskofirritation, makingpotentanti-agingandregenerativetreatments accessibletopatientswithsensitiveskin.Furthermore, industrialadvancementslikeLipoedge™demonstrate thathigh-efficiencyencapsulationandnanometricstabilityarenowachievableatscale,settinganewstandardforthepurityandperformanceoffat-solublemicronutrientsupplements.
Looking forward, the integration of liposomal VitaminAintomainstreamtherapeuticandnutricosmetic protocolsisexpectedtogrow.Asmanufacturingprocessesbecomemorerefinedandourunderstandingof cellular-levelnutrientdeliveryexpands,thesenanocarrierswillcontinuetoplayapivotalroleinprecisionnutritionandadvancedskinhealth.Thetransitionfrom conventionaloilysolutionstonanometricdeliverysystemsmarksaturningpointwherethetruephysiologicalpotentialofVitaminAcanbefullyrealizedwithout thetraditionalcompromisesoftoxicityandinstability.
Recommended Standard 700–900µgRAE(RetinolActivityEquivalents) Carazoetal.(2021); Intake AdultRDA perday.
Upper Limit TolerableMax 3,000µgRAE/day;liposomalversionsrequire Carazoetal.(2021) (UL) caution due to high absorption rates (2.36
OralSafety Metabolic Reducedliver“bolus”effect;phospholipids Carazoetal.(2021); Stress actasabuffer;potentiallydecreasingGIdis- NIH(2025)[23]
TopicalSafety SkinIrritability Significantlylowerincidenceof“retinoidder- Rahman et al.
Bioavailability Dosing Effi- Lower oral or topical concentrations may Taha et al. (2007); ciency achievetherapeuticparitywithhigher-dose NIH(2025)
ExcipientSafety Lipid Compo- Phosphatidylcholine and surfactants used WBCIL (2026); nents (e.g.,inLipoedge™)aretypicallyGRAS(Gen- Largeetal. (2021);
SpecialPopula- Pregnancy StrictCaution:Highbioavailabilityincreases Carazoetal.(2021) tions theriskofexceedingteratogenicthresholds;