Cigarettes with Reduced Tar Yield
for Standardization, founded in 1946 to promote worldwide trade and collaboration. AgenciesintheUSAincludingtheFederalTradeCommission,theFDAandtheNational
CancerInstitutearenowworkingtowardsausefulsolutiontotheproblem.TheEuropean Commissionisalsopreparingproposalsforthecorrectmeasurementoftarandnicotine
yieldsincigarettes. Afewsmokersmayactuallybeneitminimallyfromlow-tarcigarettes,butthehealth
consequencesinapositivesensehavenotyetbeendemonstrated.However,ithasbeen shownthatdeeperinhalationisassociatedwithanincreaseinadenocarcinomas,atypeof
cancerrarelyseeninthepastandaffectingthedeepsectionsoflungtissue.Onestudy publishedin1997presentedsummarydataonsmokerswhohadsmokedlightandultra-
lightcigarettesovertheperiodfrom1959to1991andwhowerefoundtohaveanincreased incidenceofadenocarcinomas;thesetumourswerefoundtooccur17timesmorecom-
monlyinwomenand10timesmorecommonlyinmen [90,91]
. In2003,Kabatpublishedareviewon50years’experienceofreduced-tarcigarettesand
posedthequestionabouttheknownhealtheffects [92]
.Itwasstatedthatsince1950s,ciga- rettessoldintheUnitedStateshaveundergoneaprogressivemodiication,includingthe
additionofiltersandareductionintheaveragemachine-measuredtarandnicotineyield percigarettebyover60.Theseandothertemporalchangesinmanufacturedcigarettes,
coupledwiththecomplexityofsmokingbehaviour,makeitdificulttoassesstheimpact ofthenewercigarettesonhealth.Someresearchershavesuggestedthatthenewerprod-
ucts,marketedasbeinglessharmful,mayinfactprovidenobeneitcomparedtotheolder, highertarcigarettes.Kabatcriticallyevaluatedtheavailableepidemiologicevidenceon
thehealtheffectsoflow-tarcigarettes.Afteridentifyingimportantmethodologicalprob- lems confronting research in this area, studies of lung cancer, coronary heart disease,
chronicobstructivepulmonarydiseaseandtotalmortalitywereexaminedintermsoftheir strengthsandweaknessesandtheirresults.Thirty-ivestudiesoflungcancerwerefound
tobesuggestivethatsmokersoflowtarcigaretteshavealowerriskby20–30com- paredtosmokersofhighertarcigarettes.Onlyaminorityofstudiesofheartdiseasepro-
videdevidenceofareductioninrisk,ontheorderof10.Studiesconcerningchronic obstructive pulmonary disease COPD were inconsistent, but the majority suggest
decreasedriskinsmokersoflowertarcigarettes.Finally,studiesthatincludedtotalmor- talityindicatedwithahighdegreeofconsistencythatthetotaldeathrateisreducedin
smokersoflowertarcigarettes,ontheorderof10–20 [92]
. However,therearealsostudiesthatindicatethattherearenomajorchangesandaddi-
tionalanalysesofexistingdatasetscouldfurtherclarifytheimpactoflow-tarcigarettes. Inthisrespect,afurtheranalysisbyThunandBurnsalsoexaminedtheepidemiological
evidencerelevanttothehealthconsequencesof“reducedyield”cigarettes [93]
.Theycon- cludethatsomeepidemiologicalstudieshavefoundattenuatedriskoflungcancer,butnot
otherdiseases,amongpeoplewhosmoke“reducedyield”cigarettescomparedtosmokers ofuniltered,highyieldproducts.Thesestudiesprobablyoverestimatedthemagnitudeof
anyassociationwithlungcancerbyoveradjustingforthenumberofcigarettessmokedper dayoneaspectofcompensatorysmokingandbynotfullyconsideringotherdifferences
betweensmokersof“highyield”and“lowyield”cigarettes.Selectedcohortstudiesinthe USAandUKwerefoundthatshowedthatlungcancerriskcontinuedtoincreaseamong
oldersmokersfromthe1950stothe1980s,despitethewidespreadadoptionofloweryield
cigarettes.Thechangetoiltertipproductswasfoundnottopreventaprogressiveincrease inlungcancerriskamongmalesmokerswhobegansmokingduringandafterthesecond
worldwarcomparedtotheirstworldwarerasmokers [93]
. Nationaltrendsinvitalstatisticsdatashoweddeclininglungcancerdeathratesinyoung
adults,especiallymales,inmanycountries,buttheextenttowhichthisisattributableto “reducedyield”cigarettesremainedunclear.Nostudieshaveadequatelyassessedwhether
healthclaimsusedtomarket“reducedyield”cigarettesdelaycessationamongsmokers who might otherwise quit, or increase initiation among non-smokers. Thun and Burns
stated that there is no convincing evidence that past changes in cigarette design have resultedinanimportanthealthbeneittoeithersmokersorthewholepopulation
[93] .