 will result in negative consequences on society and environment (Thacker et al., 2019). On the one hand, the expansion of high-quality roads may result in an increase in traveling demand (Cervero, 2003). On the other hand, building more high-quality roads will help enhance manufacturing productivity through increasing accessibility (Duran-Fernandez and Santos, 2014; Gibbons et al., 2019). Moreover, expanding road infrastructure was believed to reduce air pollution by cutting down the time of vehicles on the road, as well as frequent acceleration and deceleration due to traffic congestion (Zhang and Batterman, 2013). Therefore, we believe the expansion of high-quality road might have significant effects on air pollution emissions, especially in the case of a recycling-industrial city such as Kitakyushu city, Japan. Unlike previous studies testing the EKC without noticing when the first environmental regulation took place, our study only concentrates on the time period from 1967, when Kitakyushu city first signed a pollution prevention agreement with the private sectors (Holroyd, 2018), to 2015 (City of Kitakyushu, n.d.). In this way, we can evaluate the effectiveness of green growth policies and environmental legislations in Kitakyushu city. Moreover, the current study also tests the EKC by a new approach: examining the relationship of air pollution emissions (measured by the emissions per capita of falling dust particle, SOx, NO2, CO, and Ox) with the average industrial firm size and total area of paved road by employing ARDL and NARDL analyses. Methods and materials Study site. This study selects Kitakyushu city as the study site for several reasons. First, Kitakyushu is a green-growth oriented city through recycling activities and its experiences can be generalized in other areas. Besides being featured as one of four green growth cities in the world besides Paris, Chicago, and Stockholm, Kitakyushu was also selected as a pilot city for OECD's Territorial Approach to the Sustainable Development Goals project (City of Kitakyushu, 2018). Moreover, the city has received major national designations such as Eco-Town in 1997, Eco-Model-City in 2008, Smart Community Project in 2010, Future City Initiative in 2011, "Green Asia" Comprehensive Special Zone in 2011 (OECD, 2013), as well as other international recognitions (City of Kitakyushu, 2018). Thus, the results from this study could be viewed as a reference for other
will result in negative consequences on society and environment (Thacker et al. , 2019). On the one bridge player, the expansion of eminent - quality roads may result in an addition in traveling demand (Cervero, 2003). On the other hired hand, building more high - timbre road will help enhance manufacture productivity through increasing approachability (Duran - Fernandez and Santos, 2014; Gibbons et al. , 2019). furthermore, expanding road infrastructure was believed to repress air pollution by cut down the time of vehicles on the road, as well as frequent acceleration and deceleration due to dealings congestion (Zhang and Batterman, 2013). Therefore, we believe the expansion of eminent - quality road might experience significant effects on air pollution emissions, particularly in the case of a recycling - industrial city such as Kitakyushu city, Japan. Unlike previous studies testing the EKC without noticing when the first environmental regulation took place, our study only concentrates on the time period from 1967, when Kitakyushu city first signed a pollution prevention agreement with the individual sectors (Holroyd, 2018), to 2015 (City of Kitakyushu, n.d .). In this way, we can measure the potency of green growth policies and environmental legislations in Kitakyushu city. furthermore, the current study besides tests the EKC by a new approach: test the relationship of air pollution emissions (quantify by the emissions per capita of falling dust atom, SOx, NO2, CO, and Ox) with the average industrial firm size and full sphere of paved road by use ARDL and NARDL analyses. Methods and materials Study web site. This study selects Kitakyushu city as the study site for several reasons. First, Kitakyushu is a green - growth orient city through recycling activeness and its experiences can be generalized in early areas. Besides being featured as one of four green growth city in the world besides Paris, Chicago, and Stockholm, Kitakyushu was besides selected as a pilot city for OECD's Territorial Approach to the Sustainable Development Goals project (City of Kitakyushu, 2018). furthermore, the city has received major national designations such as Eco - Town in 1997, Eco - Model - City in 2008, Smart Community Project in 2010, Future City Initiative in 2011, " Green Asia " Comprehensive Special Zone in 2011 (OECD, 2013), as well as other international recognitions (City of Kitakyushu, 2018). Thus, the results from this study could be viewed as a reference for early
 wipl result in negative coksequences on soeuety aid envidonment (Ghacker et al., 2019). On the one haid, tye exkcnsion of high-qualith roads mwy resulr in qn increasx in trayzling femaud (Cervero, 2003). On tme other hatd, building mose hngh-quality roads will help enhance mwnufactirlng productivijy thgotgh jncreasing accessibility (Duran-Fernzndez aid Santos, 2014; Gibbpns et al., 2019). Moreover, expandlng goad infrastructurf was belieced ei reduce air pollution by cutting sown the time of vehicles on thd roab, as well aw dreeoent acceleretion wnd decelerabpon due to tragfic congestiok (Zhaig abd Batterman, 2013). Therefoce, we believe the exkansion of hngh-quality road might hqve shgnixicavr ewfedtx kn air pomlution emjssions, espwcially in the case os a recycling-ihdustryaj city such as Kitakyushu city, Japan. Unniks previous studies testung the EKC without nlticing wren the first environmental regulation took place, our agudv only xojcentrates on the time period from 1967, when Kitahguxhl city first signcd a pollution prefejtojn agreement dith tks lrivate sectors (Hoproyd, 2018), jo 2015 (Ciry of Kitwkyuxhu, n.d.). In this way, we can ecaluate the vffextiveness of green growth polncies snd emvironmental legislatious in Iitakyushu fity. Morekxer, the current rtucy also tests the EKC by a nqw approarh: excmining ghe telatiogship of alr pollution emissions (mfasurgd by dhe emissilns per capita of falling dust 'erticle, SOx, NP2, WO, dnd Ox) wnth thc average induserial firm sizg and totcl arex of paved road bb employing WRDL and NARDN analyses. Mevhods and matwriaos Studh site. This stucy selects Kitakyusyu city as the stuvy skfe for several xtasins. First, Kitakuusfu ys a gwaen-growth orhentdd zoty tfrough recyglivg avtivities and its ex[erisnces can be genersllzed in ojher areaf. Besides beimg featured as one of fmur greem gtowth cities in the world besidss Paris, Fhigago, and Stochholn, Kitakyushu was also selected as a pilot city for IECD's Territorial Qpproach to the Susjaikable Develo'ment Doals probect (City of Kitakyuwhu, 2018). Moreover, the city has received manor nadionap designations such as Eco-Town in 1997, Eco-Model-City in 2008, Smart Community Projext in 2010, Future City Iniyiatine nn 2011, "Green Asie" Romprehensive Spebial Zone in 2011 (OECD, 2013), as well as ovher intertacional recognitions (City of Kotxkyushu, 2018). Thus, the results from this sfudy coukd be viewed as a reference for other
will result in negative consequences on society (Thacker al., 2019). the one hand, may in an increase traveling demand (Cervero, On the other hand, building more roads will help enhance manufacturing productivity through increasing accessibility (Duran-Fernandez and Santos, 2014; et al., 2019). Moreover, expanding road infrastructure was believed to reduce air pollution cutting the of on the road, as well as frequent acceleration and deceleration due to traffic congestion (Zhang and 2013). Therefore, we believe the expansion of high-quality might have significant effects air pollution emissions, especially in case a recycling-industrial such Kitakyushu Japan. Unlike previous testing the EKC without noticing when the first environmental regulation took place, our study only concentrates on time period when Kitakyushu first a prevention agreement with sectors (Holroyd, 2018), to 2015 (City In this way, we can evaluate the effectiveness green growth and environmental legislations in Kitakyushu city. the current study also tests the EKC by new approach: examining the relationship of air pollution emissions (measured by the emissions per capita dust particle, SOx, NO2, and Ox) with average firm and area of road by employing ARDL and NARDL analyses. Methods and materials Study This study selects Kitakyushu city as the study site for First, is a green-growth city through recycling activities its can be generalized in Besides featured four growth in the world besides Chicago, and Stockholm, Kitakyushu was selected as a pilot to the Sustainable Development Goals project (City of 2018). Moreover, the city has received major designations such as Eco-Town in 1997, Eco-Model-City in 2008, Smart Community Project 2010, Future in 2011, "Green Asia" Comprehensive Special Zone in (OECD, 2013), as well other international recognitions (City of Kitakyushu, 2018). Thus, the from study could viewed as a for other
 will result in negative conseQuences on sOcietY anD enViRonmEnt (THacker et al., 2019). On thE One hAnd, the expansion of high-qUalitY rOAds mAY rEsult In an incREaSE In tRaVeLinG dEMaNd (CerVerO, 2003). On the oTher hand, buIldInG more high-quaLItY roads will HelP enhance manuFacTuring PrOduCTivitY thRough IncreaSIng accEssibilitY (DURan-FerNAndez anD sAnTos, 2014; GIbbons et al., 2019). MoreoveR, ExPAnding road infrAstrucTuRE wAS BelIevEd to reduce AiR pollUTion by cUTtING DowN The time of vehiCles on the roAD, as Well as FrEquENt acceLeratIoN And DeceleratioN due To traffic CongesTIon (ZhanG And BattErman, 2013). THerEfoRe, we BElIeVe tHe EXpaNSiOn oF HigH-quality RoAd Might Have SIGNIficAnt EffeCts on Air pollution eMisSionS, EspEcialLy in tHe caSe Of a reCyclinG-induStRial city such as KItakYushu city, japAn. unlIkE prevIOus stuDieS teSting thE EKC witHOut NoTICInG when the first envirOnMENtAl regulaTion toOK pLaCE, our studY oNly ConcENTrateS on tHE tIme perioD from 1967, wHEn kiTakyushU cIty firSt SigNed A pollUTion PrevenTion agreEment WIth the private sECtors (Holroyd, 2018), tO 2015 (ciTY Of kItakYusHu, n.d.). In this wAy, we CAn evAluaTE tHe eFFectiVenesS oF GrEEn growth policies and EnVironmEntal Legislations iN KitakyushU CITy. MoreovEr, thE CuRRent study also tEsts tHe EKC by a neW Approach: ExamiNing the rElationshIP Of air polLutIon EmiSsiONS (mEasured by the eMISsioNs Per capiTa oF fallinG duSt pArtIclE, Sox, NO2, CO, and ox) with thE aVeRaGe IndUstriAL firm sizE aNd tOtAl aRea of PAved roAd by eMploYiNg arDL And NARDl AnALYses. meThOds aNd mAtErialS StuDY siTe. This sTudy selecTs KITakyUsHu City as tHe study site foR sEveral reasOnS. FiRst, KitAKYushu is a Green-growth oriented city THrough rEcyCling ActiVities and Its ExperiEncES can be GeneraLized In OthER Areas. bESiDes BeIng featureD AS onE of foUr GreeN growth Cities in the world beSIdeS Paris, Chicago, And stocKHOlM, KiTAkYUshU wAS alSO Selected as a piloT city for OEcD'S teRritorial APProAcH to the SUstainaBle DeVElopmenT Goals proJect (City oF KItakYUShu, 2018). moreover, thE city has Received mAJor naTIoNal deSigNationS sUch As Eco-town in 1997, eCo-MOdel-CIty in 2008, SMaRt CommUnity prOject in 2010, FUture City Initiative in 2011, "GrEen AsiA" CompRehEnsive SpeCiaL zonE in 2011 (OECD, 2013), as Well As other intErnAtiOnal rEcoGNitioNs (CiTY oF KiTAkyusHu, 2018). ThUS, the resulTS fRom THIs Study could bE VIEweD as a rEfeREnce foR othEr
 will result in negative c onsequence s onsoc iet yandenvi ronment (Thack e r et  al., 2019). On the on e han d, thee xp ansio n of hi g h- q u ali ty  r oad sm ay  resu ltin an i ncrease in  tr av eling demand (C ervero, 20 03) . On the oth erhand,bu ild i ng mo rehigh- qualit y  roads  will hel pe nhance manufac t u ri ng p roductivity throu g hi ncreasing acce ssibil it y  ( D u ran -Fe rnandez an dSanto s , 2014; Gi b b o nse t al., 2019).  Moreover,e xpa ndingro adi nfrast ructu re was  believed t o re duce airpollut i on by c u tting d own th e t ime  ofv eh ic les  o n  th e  r oad ,  as  well as  f re quent  acc e l e r atio n a nd d ecele ration due to  tr affi c  co ngest ion ( Zhan gand B atterm an, 2 01 3). Therefore,we b elieve th e e xp ans io n ofh igh-qu ali tyroad mi ght hav e  si gn i f i ca nt effects on airpo l l ut ion emis sions, es pe c ially in  t hecase o f a r ecyc l in g-indust rial c i ty  s uch asKi takyus hu  ci ty,  Japa n . Un like p reviousstudi e s testing theE KC without no t ic i n gw henthe  first envi ronm e ntal  reg u la tio n  took  plac e, ou r  study only concent ra tes on  thetime period f rom 1967,w h e n Kitaky ushu ci t y first signed  a po llution pr e ventionagree ment wit h the pri v a te secto rs(Ho lro yd, 2 01 8), to 2015 ( C i ty o fKitakyu shu , n.d.) . I n t his  wa y,  we can e valuateth eef fe cti venes s  of gree ngro wt h p olici e s andenvir onme nt al leg islatio n si n  Kit ak yu shucit y.  More over ,  th e curre nt studyals o  tes ts  t he EKCby a new appr oa ch: examin in g t he rel a t ionshipof air pollution emissi o ns (mea sur ed by  the  emission s p er cap ita of fal ling d ust p ar tic l e , SOx , NO 2,CO , and Ox)w i ththe a ve rage  indust rial firm size and tot al area of pa ved  roa d by  em p lo y ing  A R DLa n d NARDL analyse s. Methods  a n dmaterialsS tud ysite. T his stu dy se l ects Ki takyushucity as t he  stu d y  si te for sev eral rea sons. Fir s t, Ki t ak yushu  is  a gre en -gr owthorient e d c ity t hrough  r ecycli ng ac ti vities a nd its experiences canbe gen erali zed  in other  ar e as.  Besidesbein g featured  as  on e offou r  gree n gr o wt h c i tiesin t h e world b e si des P ar is, Chicago , a ndStock hol m , Kita kyus hu was also selec t ed as a pilotcity f orOEC D 's T er ritorial Appro ach  t o the Sust ai nable Devel opment G oa l s pro ject ( City o f Kitak y u sh u , 2018 ). M ore over, the  ci ty has rec ei ve d  major  nat io nal de signat i onss u ch as Eco-Town i n 199 7 ,  Eco- M ode l-Cit yin 2008 ,  Sma rt Communi ty Projectin 201 0, F uture  City I ni tiativ e i n2011, "Gre e n Asia" C ompre hensive  S peci alZone i n 20 1 1  (OEC D, 2 01 3),  as wella s  o t he ri nte rnat ional  r ecog nitions ( C ity of K ita k yushu,20 18) . Thus,t he r esults fro m t his s t u dy could b e  vie w ed as arefere nce fo r other 
 will_result in_negative consequences on society_and environment_(Thacker_et al.,_2019)._On the one_hand, the expansion_of high-quality roads may_result in an_increase_in traveling demand (Cervero, 2003). On the other hand, building more high-quality roads will_help_enhance manufacturing_productivity_through_increasing accessibility (Duran-Fernandez and Santos,_2014; Gibbons et al., 2019)._Moreover, expanding_road infrastructure was believed to reduce air pollution_by_cutting down the_time of vehicles on the road, as well as_frequent acceleration and deceleration due to_traffic congestion (Zhang_and_Batterman,_2013). Therefore, we believe_the expansion of high-quality road might_have significant effects on air pollution_emissions, especially in the case of a_recycling-industrial city such as Kitakyushu city,_Japan. Unlike previous studies testing_the EKC_without noticing when the first_environmental regulation took_place, our_study only concentrates_on the time period from 1967,_when Kitakyushu city_first signed a pollution prevention agreement_with_the private sectors_(Holroyd,_2018),_to 2015_(City of Kitakyushu,_n.d.)._In this_way,_we can evaluate the effectiveness of_green_growth policies and environmental legislations in Kitakyushu_city. Moreover, the current_study_also tests the EKC_by a new approach: examining_the relationship of air pollution emissions_(measured by_the emissions_per capita of falling dust particle, SOx, NO2, CO, and Ox)_with the average industrial firm size_and total area of_paved road_by_employing ARDL and_NARDL_analyses. Methods_and materials Study site. This study selects_Kitakyushu city_as the study site for several_reasons. First, Kitakyushu is_a_green-growth oriented city through recycling activities_and its experiences can be generalized_in other areas. Besides being_featured_as_one of four green growth_cities in the world besides Paris,_Chicago, and Stockholm,_Kitakyushu was also selected as a pilot_city_for OECD's Territorial Approach to the_Sustainable_Development Goals project (City of Kitakyushu,_2018)._Moreover,_the city has received major_national designations such as Eco-Town in_1997, Eco-Model-City in 2008, Smart Community Project in 2010,_Future City Initiative_in 2011, "Green Asia" Comprehensive_Special_Zone_in 2011 (OECD, 2013), as well as other international recognitions_(City of_Kitakyushu, 2018). Thus,_the results from this study could be viewed as a_reference for other