Behavioral variations and their effects on traffic-related PM_2.5 inhalation exposure: findings from three cross-sectional surveys (2015-2020)

Abstract

Traffic-related activity patterns, including transportation mode choices and time spent in transit, critically influence individuals’ exposure to air pollution. This study analyzed data from three cross-sectional surveys conducted in Lanzhou, China (2015-2020), to investigate variations in transportation behavior and their impact on daily cumulative PM_2.5 inhalation exposure. Results showed that walking was the most frequently used mode, accounting for over 70% of trips, while car use involved the longest average travel time - exceeding 60 min per day. However, trends in mode share and usage time were not synchronized, and the use of different transportation modes was interrelated. Sociodemographic factors and built environment features near homes and workplaces were dynamically associated with transportation behaviors. Time spent in transit had the strongest influence on cumulative daily exposure, explaining more than 90% of the variation across modes. Open modes of transport were linked to the highest exposure levels due to elevated pollutant concentrations and increased inhalation rates, whereas car transportation resulted in the lowest exposure despite its longer duration. These findings underscore the need to incorporate transportation behavior into air pollution exposure assessments and suggest that transportation policies and infrastructure planning should align mobility objectives with public health priorities.

Keywords

Traffic-related activity / behavioral variations / transportation mode / cumulative inhalation exposure

References

[1] Mandalakis M,Horii Y.Emerging contaminants in car interiors: evaluating the impact of airborne PBDEs and PBDD/Fs.Environ Sci Technol2008;42:6431-6

[2] Saraswat A,Brauer M.PM_2.5 population exposure in new delhi using a probabilistic simulation framework.Environ Sci Technol2016;50:3174-83

[3] Ma X,Gao J.Evaluating the effect of ambient concentrations, route choices, and environmental (in)justice on students’ dose of ambient NO₂ while walking to school at population scales.Environ Sci Technol2020;54:12908-19

[4] Künzli N,Medina S.Public-health impact of outdoor and traffic-related air pollution: a European assessment.Lancet2000;356:795-801

[5] Garcia L,Johnson A.Health impacts of changes in travel patterns in Greater Accra Metropolitan Area, Ghana.Environ Int2021;155:106680 PMCID:PMC7612136

[6] Beelen R,van den Brandt PA.Long-term effects of traffic-related air pollution on mortality in a Dutch cohort (NLCS-AIR study).Environ Health Perspect2008;116:196-202 PMCID:PMC2235230

[7] Celis-Morales CA,Welsh P.Association between active commuting and incident cardiovascular disease, cancer, and mortality: prospective cohort study.BMJ2017;357:j1456

[8] Nordling E,Melén E.Traffic-related air pollution and childhood respiratory symptoms, function and allergies.Epidemiology2008;19:401-8

[9] Aziz K,Nasir ZA.Comparative study of particulate matter in the transport microenvironment (buses) of Pakistan and UK.J Anim Plant Sci2015;25:636-43http://dspace.lib.cranfield.ac.uk/handle/1826/14164. (accessed 18 Jul 2025)

[10] Brauer M,Tamburic L,Demers P.A cohort study of traffic-related air pollution impacts on birth outcomes.Environ Health Perspect2008;116:680-6 PMCID:PMC2367679

[11] McConnell R,Shankardass K.Childhood incident asthma and traffic-related air pollution at home and school.Environ Health Perspect2010;118:1021-6 PMCID:PMC2920902

[12] Min KD,Kim HC.Association between exposure to traffic-related air pollution and pediatric allergic diseases based on modeled air pollution concentrations and traffic measures in Seoul, Korea: a comparative analysis.Environ Health2020;19:6 PMCID:PMC6961284

[13] Ma X,Gao J,Salmond J.A site-optimised multi-scale GIS based land use regression model for simulating local scale patterns in air pollution.Sci Total Environ2019;685:134-49

[14] Forehead H.Review of modelling air pollution from traffic at street-level - The state of the science.Environ Pollut2018;241:775-86

[15] Singh V,Agarwal A.Travellers’ exposure to air pollution: a systematic review and future directions.Urban Climate2021;38:100901

[16] Goel R,Guttikunda SK,Tiwari G.On-road PM_2.5 pollution exposure in multiple transport microenvironments in Delhi.Atmos Environ2015;123:129-38

[17] Harrad S,Ibarra C.Concentrations of polychlorinated biphenyls in indoor air and polybrominated diphenyl ethers in indoor air and dust in Birmingham, United Kingdom: implications for human exposure.Environ Sci Technol2006;40:4633-8

[18] Abdillah SFI,Wang YF.Characterizing sector-oriented roadside exposure to ultrafine particles (PM_0.1) via machine learning models: Implications of covariates influences on sectors variability.Environ Pollut2024;359:124595

[19] Yang F,Wong KC.Heterogeneity of passenger exposure to air pollutants in public transport microenvironments.Atmos Environ2015;109:42-51

[20] Borghi F,Fanti G.Commuters’ personal exposure assessment and evaluation of inhaled dose to different atmospheric pollutants.Int J Environ Res Public Health2020;17:3357 PMCID:PMC7277859

[21] de Kluizenaar Y,Eekhout I.Personal exposure to UFP in different micro-environments and time of day.Build Environ2017;122:237-46

[22] Dons E,Van Poppel M,Wets G.Personal exposure to Black Carbon in transport microenvironments.Atmos Environ2012;55:392-8

[23] Dons E,Van Poppel M.Impact of time-activity patterns on personal exposure to black carbon.Atmos Environ2011;45:3594-602

[24] Shafran-Nathan R,Broday DM.Impacts of personal mobility and diurnal concentration variability on exposure misclassification to ambient pollutants.Environ Sci Technol2018;52:3520-6

[25] Rind E,Mitchell R,Pearce J.Are income-related differences in active travel associated with physical environmental characteristics? A multi-level ecological approach.Int J Behav Nutr Phys Act2015;12:73 PMCID:PMC4461897

[26] Watson KB,Bricka S.Purpose-based walking trips by duration, distance, and select characteristics, 2017 National Household Travel Survey.J Phys Act Health2021;18:S86-93 PMCID:PMC8743872

[27] Gong W,Feng G.Trends in transportation modes and time among Chinese population from 2002 to 2012.Int J Environ Res Public Health2020;17:945 PMCID:PMC7036899

[28] D’Agostino EM,Alexander EP,Neshteruk CD.Predictors and patterns of physical activity from transportation among United States Youth, 2007-2016.J Adolesc Health2021;69:263-71

[29] Liu X,Ni A.Understanding better the influential factors of commuters’ multi-day travel behavior: evidence from Shanghai, China.Sustainability2020;12:376

[30] Branion-Calles M,Koehoorn M,Harris MA.Estimating walking and bicycling in Canada and their road collision fatality risks: the need for a national household travel survey.Prev Med Rep2021;22:101366 PMCID:PMC8058556

[31] Yang Y,Liu W.Understanding the determinants of travel mode choice of residents and its carbon mitigation potential.Energy Policy2018;115:486-93

[32] Nguyen-Phuoc DQ,Tran ATP.Mode choice among university students to school in Danang, Vietnam.Travel Behav Soc2018;13:1-10

[33] Li J,Guo M.Do Socio-economic characteristics affect travel behavior? A comparative study of low-carbon and non-low-carbon shopping travel in Shenyang City, China.Int J Environ Res Public Health2018;15:1346 PMCID:PMC6068570

[34] Yu CY.Exploring factors regarding transit-related walking and walking duration.J Phys Act Health2016;13:1220-9

[35] Greaves SP.Capturing the spatiotemporal variability of fine particulates in travel microenvironments using GPS technology. In Proceedings of the 12th International Conference on Urban Transport and the Environment in the 21st Century, Prague, Czech republic. Jul 12-14, 2006. pp. 849-58.

[36] Mitsakou C,Doutsi A.Assessing the exposure to air pollution during transport in urban areas - evidence review.J Transp Health2021;21:101064

[37] Kaur S,Colvile R.Fine particulate matter and carbon monoxide exposure concentrations in urban street transport microenvironments.Atmos Environ2007;41:4781-810

[38] Miao Q,Chen D,Aronson KJ.Commuting behaviors and exposure to air pollution in Montreal, Canada.Sci Total Environ2015;508:193-8

[39] Suárez L,Iglesias V,Cáceres DD.Personal exposure to particulate matter in commuters using different transport modes (bus, bicycle, car and subway) in an assigned route in downtown Santiago, Chile.Environ Sci Process Impacts2014;16:1309-17

[40] Tsai DH,Chan CC.Comparisons of commuter’s exposure to particulate matters while using different transportation modes.Sci Total Environ2008;405:71-7

[41] Adams H,Colvile R,Kendall M.Assessment of road users’ elemental carbon personal exposure levels, London, UK.Atmos Environ2002;36:5335-42

[42] Wu D,Chan C.Influences of commuting mode, air conditioning mode and meteorological parameters on fine particle (PM_2.5) exposure levels in traffic microenvironments.Aerosol Air Qual Res2013;13:709-20

[43] Jiang N,Wang B.Traffic related activity pattern of Chinese adults: a nation-wide population based survey.J Expo Sci Environ Epidemiol2023;33:482-9

[44] Wu L,Jing P.Travel mode choice and their impacts on environment - a literature review based on bibliometric and content analysis, 2000-2018.J Clean Prod2020;249:119391

[45] Feng J,Wissink B.Changing travel behaviour in urban China: evidence from Nanjing 2008-2011.Transp Policy2017;53:1-10

[46] Boniardi L,Straccini S.Commuting by car, public transport, and bike: exposure assessment and estimation of the inhaled dose of multiple airborne pollutants.Atmos Environ2021;262:118613

[47] EPA. Exposure factors handbook (2011 edition). https://www.epa.gov/expobox/exposure-factors-handbook-2011-edition. (accessed 18 Jul 2025)

[48] Li Y,Li K.Commuter exposure to PM2.5 and its influencing factors in different commuting modes.Environ Chem2015;34:1408-16https://caod.oriprobe.com/articles/46834431/Commuter_exposure_to_PM2_5_and_its_influencing_fac.htm. (accessed 18 Jul 2025)

[49] Lanzhou Ecology and Environment Bureau. Report on the State of the Environment. https://sthjj.lanzhou.gov.cn/col/col5758/index.html. (accessed 18 Jul 2025)

[50] McNabola A,Gill LW.A principal components analysis of the factors effecting personal exposure to air pollution in urban commuters in Dublin, Ireland.J Environ Sci Health A Tox Hazard Subst Environ Eng2009;44:1219-26

[51] Qiu Z,Xu X.Commuter exposure to particulate matter for different transportation modes in Xi’an, China.Atmos Pollut Res2017;8:940-8

[52] Goodman A.Walking, cycling and driving to work in the English and Welsh 2011 census: trends, socio-economic patterning and relevance to travel behaviour in general.PLoS One2013;8:e71790 PMCID:PMC3749195

[53] Gali NK,Yang F,Ning Z.Redox characteristics of size-segregated PM from different public transport microenvironments in Hong Kong.Air Qual Atmos Health2017;10:833-44

[54] Duan X,Wang B,Cao S. 5 - Time-activity factors related to air exposure. In Highlights of the Chinese Exposure Factors Handbook (Adults). Academic Press: 2015; pp. 31-9. https://www.researchgate.net/publication/294645842_Highlights_of_the_Chinese_Exposure_Factors_HandbookAdults. (accessed 18 Jul 2025)

[55] Zulauf N,Klingelhöfer D,Oremek GM.Indoor air pollution in cars: an update on novel insights.Int J Environ Res Public Health2019;16:2441 PMCID:PMC6650813

[56] Jin H,Wang J,Dong L.Competition and cooperation between shared bicycles and public transit: a case study of Beijing.Sustainability2019;11:1323

[57] Ji W,Mao J,Hou M.Public’s intention and influencing factors of dockless bike-sharing in central urban areas: a case study of Lanzhou City, China.Sustainability2021;13:9265

[58] Campbell KB.Sharing riders: how bikesharing impacts bus ridership in New York City.Transp Res Part A Policy Pract2017;100:264-82

[59] Cao M,Huang M,Chen M.Effects of free-floating shared bicycles on urban public transportation.IJGI2019;8:323

[60] Zhou X,Ji X.The influence of information services on public transport behavior of urban and rural residents.Sustainability2019;11:5454

[61] Lidbe A,Penmetsa P.Changes in the travel patterns of older Americans with medical conditions: a comparison of 2001 and 2017 NHTS data.Transp Res Interdiscip Perspect2021;11:100463

[62] Gascon M,de Nazelle A.Correlates of walking for travel in seven European cities: the PASTA Project.Environ Health Perspect2019;127:97003

[63] Qiu Z,Zhang F,Hao Y.Pedestrian exposure to PM_2.5, BC and UFP of adults and teens: a case study in Xi’an, China.Sustain Cities Soc2019;51:101774

[64] Gilliland J,Xu X,Shah T.Influence of the natural and built environment on personal exposure to fine particulate matter (PM_2.5) in cyclists using city designated bicycle routes.Urban Sci2018;2:120

[65] Okokon EO,Turunen AW.Particulates and noise exposure during bicycle, bus and car commuting: a study in three European cities.Environ Res2017;154:181-9

[66] Bigazzi AY.Review of urban bicyclists’ intake and uptake of traffic-related air pollution.Transp Rev2014;34:221-45

[67] Hatzopoulou M,Barreau G.A web-based route planning tool to reduce cyclists’ exposures to traffic pollution: a case study in Montreal, Canada.Environ Res2013;123:58-61

[68] Ham W,Schulte N.Commuter exposure to PM_2.5, BC, and UFP in six common transport microenvironments in Sacramento, California.Atmos Environ2017;167:335-45