Imperial College London

DrAudreyde Nazelle

Faculty of Natural SciencesCentre for Environmental Policy

Senior Lecturer



+44 (0)20 7594 7319anazelle Website




20416 Prince's GardensSouth Kensington Campus





Publication Type

165 results found

Woodward H, Schroeder A, de Nazelle A, Pain CC, Stettler MEJ, ApSimon H, Robins A, Linden PFet al., 2023, Do we need high temporal resolution modelling of exposure in urban areas? A test case, Science of the Total Environment, Vol: 885, Pages: 163711-163711, ISSN: 0048-9697

Roadside concentrations of harmful pollutants such as NOx are highly variable in both space and time. This is rarely considered when assessing pedestrian and cyclist exposures. We aim to fully describe the spatio-temporal variability of exposures of pedestrians and cyclists travelling along a road at high resolution. We evaluate the value added of high spatio-temporal resolution compared to high spatial resolution only. We also compare high resolution vehicle emissions modelling to using a constant volume source. We highlight conditions of peak exposures, and discuss implications for health impact assessments. Using the large eddy simulation code Fluidity we simulate NOx concentrations at a resolution of 2 m and 1 s along a 350 m road segment in a complex real-world street geometry including an intersection and bus stops. We then simulate pedestrian and cyclist journeys for different routes and departure times. For the high spatio-temporal method, the standard deviation in 1 s concentration experienced by pedestrians (50.9 μg.m-3) is nearly three times greater than that predicted by the high-spatial only (17.5 μg.m-3) or constant volume source (17.6 μg.m-3) methods. This exposure is characterised by low concentrations punctuated by short duration, peak exposures which elevate the mean exposure and are not captured by the other two methods. We also find that the mean exposure of cyclists on the road (31.8 μg.m-3) is significantly greater than that of cyclists on a roadside path (25.6 μg.m-3) and that of pedestrians on a sidewalk (17.6 μg.m-3). We conclude that ignoring high resolution temporal air pollution variability experienced at the breathing time scale can lead to a mischaracterization of pedestrian and cyclist exposures, and therefore also potentially the harm caused. High resolution methods reveal that peaks, and hence mean exposures, can be meaningfully reduced by avoiding hyper-local hotspots such as bus stops and junctions.

Journal article

Kirkpatrick L, Adjiman C, ApSimon H, Berry A, de Nazelle A, Mijic A, Myers R, Woodward G, Workman Met al., 2023, Systems thinking for the transition to zero pollution, Systems thinking for the transition to zero pollution,, Publisher: Grantham Institute, 40

Systems approaches are vital for coordinating decision-making in the face of complex issues because they provide the whole picture view needed to avoid negative unintended consequences and to generate genuine benefits. This paper explains how systems thinking can be used to address environmental pollution and support decision-makers in finding solutions.


Fan H, Cheng S, de Nazelle AJ, Arcucci Ret al., 2023, An Efficient ViT-Based Spatial Interpolation Learner for Field Reconstruction, Computational Science – ICCS 2023, Publisher: Springer Nature Switzerland, Pages: 430-437, ISBN: 9783031360268

Book chapter

Yang X, McCoy E, Hough K, de Nazelle Aet al., 2022, Evaluation of low traffic neighbourhood (LTN) impacts on NO2 and traffic, Transportation Research Part D: Transport and Environment, Vol: 113, Pages: 1-11, ISSN: 1361-9209

Traffic restriction measures may create safer and healthier places for community members but may also displace traffic and air pollution to surrounding streets. Effective urban planning depends on understanding the magnitude of changes resulting from policy measures, both within and surrounding intervention areas; these are largely unstudied in the case of Low traffic Neighbourhoods (LTN). We evaluated impacts of three LTNs in the London Borough of Islington, UK, on air pollution and traffic flows in and around intervention areas, based on monthly Nitrogen Dioxide (NO2) and traffic volume data provided by the local authority. We identified pre- and post-intervention monitoring periods and intervention, boundary and control sites. We then adapted the generalised difference in differences approach to evaluate the effects within LTNs and at their boundary. We found that LTNs have the potential to substantially reduce air pollution and traffic in target areas, without increasing air pollution or traffic volumes in surrounding streets. These results provide sound arguments in favour of LTNs to promote health and wellbeing in urban communities.

Journal article

Yang X, Orjuela JP, McCoy E, Vich G, Anaya-Boig E, Avila-Palencia I, Brand C, Carrasco-Turigas G, Dons E, Gerike R, Gotschi T, Nieuwenhuijsen M, Panis LI, Standaert A, de Nazelle Aet al., 2022, The impact of black carbon (BC) on mode-specific galvanic skin response (GSR) as a measure of stress in urban environments, Environmental Research, Vol: 214, ISSN: 0013-9351

Previous research has shown that walking and cycling could help alleviate stress in cities, however there is poor knowledge on how specific microenvironmental conditions encountered during daily journeys may lead to varying degrees of stress experienced at that moment. We use objectively measured data and a robust causal inference framework to address this gap. Using a Bayesian Doubly Robust (BDR) approach, we find that black carbon exposure statistically significantly increases stress, as measured by Galvanic Skin Response (GSR), while cycling and while walking. Augmented Outcome Regression (AOR) models indicate that greenspace exposure and the presence of walking or cycling infrastructure could reduce stress. None of these effects are statistically significant for people in motorized transport. These findings add to a growing evidence-base on health benefits of policies aimed at decreasing air pollution, improving active travel infrastructure and increasing greenspace in cities.

Journal article

Cruz-Piedrahita C, Roscoe C, Howe C, Fecht D, de Nazelle Aet al., 2022, Holistic approach to assess the association between the synergistic effect of physical activity, exposure to greenspace, and fruits and vegetable intake on health and wellbeing: Cross-sectional analysis of UK Biobank, Frontiers in Public Health, Vol: 10, Pages: 1-16, ISSN: 2296-2565

Background: Urban agriculture has been shown to contribute to healthy lifestyle behaviors, such as increased fruit and vegetable intake and greater exposure to greenspaces and there is plenty of evidence linking these lifestyle behaviors to better health and wellbeing. However, most evidence relates to assessing one behavior at a time despite available epidemiological research showing how the combined effects of multiple behaviors are associated with health and wellbeing. This research aims to examine the association of the interactions between various lifestyle behaviors and exposures related to urban agriculture and health and wellbeing.Methods: We used data from the UK Biobank baseline questionnaire (N~500, 000) to assess the association of two lifestyle behaviors (fruit and vegetable intake and physical activity) and greenspace exposure, with four health and wellbeing markers (blood pressure, BMI, self-health assessment, and self-reported loneliness) independently, and in combination. Associations between lifestyle behaviors, greenspace exposure, and the possible interactions with health and wellbeing were explored using general linear models (GLMs), adjusted for socio-demographic confounders including age, sex, educational qualifications, index of multiple deprivation, and ethnicity, and a lifestyle confounder: smoking status.Results: After removing missing data, as well as participants who did not meet the inclusion criteria, the final study sample was n = 204,478. The results indicate that meeting recommended levels of the World Health Organization (WHO) for fruits and vegetable intake, and the advice from the UK Chief Medical Officer for physical activity, is linked to better health and wellbeing markers. We found that UK Biobank participants who lived in greener areas and were physically active were more likely to feel alone and think their health was poor. Participants who were physically active and met the recommended intake of fruits and vegetables were

Journal article

Olsen JR, Nicholls N, Caryl F, Mendoza JO, Panis LI, Dons E, Laeremans M, Standaert A, Lee D, Avila-Palencia I, de Nazelle A, Nieuwenhuijsen M, Mitchell Ret al., 2022, Day-to-day intrapersonal variability in mobility patterns and association with perceived stress: A cross-sectional study using GPS from 122 individuals in three European cities, SSM - Population Health, Vol: 19, Pages: 1-10, ISSN: 2352-8273

Many aspects of our life are related to our mobility patterns and individuals can exhibit strong tendencies towards routine in their daily lives. Intrapersonal day-to-day variability in mobility patterns has been associated with mental health outcomes. The study aims were: (a) calculate intrapersonal day-to-day variability in mobility metrics for three cities; (b) explore interpersonal variability in mobility metrics by sex, season and city, and (c) describe intrapersonal variability in mobility and their association with perceived stress.Data came from the Physical Activity through Sustainable Transport Approaches (PASTA) project, 122 eligible adults wore location measurement devices over 7-consecutive days, on three occasions during 2015 (Antwerp: 41, Barcelona: 41, London: 40). Participants completed the Short Form Perceived Stress Scale (PSS-4). Day-to-day variability in mobility was explored via six mobility metrics using distance of GPS point from home (meters:m), distance travelled between consecutive GPS points (m) and energy expenditure (metabolic equivalents:METs) of each GPS point collected (n = 3,372,919). A Kruskal-Wallis H test determined whether the median daily mobility metrics differed by city, sex and season. Variance in correlation quantified day-to-day intrapersonal variability in mobility. Levene's tests or Kruskal-Wallis tests were applied to assess intrapersonal variability in mobility and perceived stress.There were differences in daily distance travelled, maximum distance from home and METS between individuals by sex, season and, for proportion of time at home also, by city. Intrapersonal variability across all mobility metrics were highly correlated; individuals had daily routines and largely stuck to them. We did not observe any association between stress and mobility.Individuals are habitual in their daily mobility patterns. This is useful for estimating environmental exposures and in fuelling simulation studies.

Journal article

Tiernan H, Friedman S, Clube RKM, Burgman MA, Castillo AC, Stettler MEJ, Kazarian SG, Wright S, De Nazelle Aet al., 2022, Implementation of a structured decision-making framework to evaluate and advance understanding of airborne microplastics, Environmental Science and Policy, Vol: 135, Pages: 169-181, ISSN: 1462-9011

Microplastic pollution is increasingly recognised as a global environmental challenge which stems from the rapid growth of the use of petrochemical-derived plastic. As researchers and practitioners face a myriad of environmental challenges, oceanic microplastic pollution has so far dominated interest. However, airborne microplastics present an increasing environmental and public health concern. There is currently a need for research addressing this emerging challenge, and at the same time, the lack of knowledge and consensus regarding airborne microplastics presents an obstacle to action. The purpose of this study is to utilise a participatory Structured Decision-Making (SDM) approach to understand the perspectives of a range of stakeholders involved in the microplastics landscape, and subsequently refine common research priorities and knowledge gaps to advance the field. Through two participatory workshops, we first defined shared objectives of stakeholders and then negotiated best courses of action to achieve these objectives based on discussion between stakeholders and facilitators. The qualitative approach taken has enabled the full, complex and multidisciplinary aspects of the research into airborne microplastic pollution to be considered. Our findings highlight some important potential consequences of airborne microplastic pollution, including impacts on human health, and the need for more interdisciplinary research, and collaborative, integrated approaches in this area. As a result of the first workshop, five fundamental objectives on the theme of airborne microplastics were identified. As a direct consequence of this, participants identified 84 actions split across eight themes, which are outlined later in this paper.

Journal article

Barban P, De Nazelle A, Chatelin S, Quirion P, Jean Ket al., 2022, Assessing the health benefits of physical activity due to active commuting in a French energy transition scenario, International Journal of Public Health, Vol: 67, Pages: 1-11, ISSN: 0303-8408

Objectives: Energy transition scenarios are prospective outlooks describing combinations of changes in socio-economic systems that are compatible with climate targets. These changes could have important health co-benefits. We aimed to quantify the health benefits of physical activity caused by active transportation on all-cause mortality in the French negaWatt scenario over the 2021–2050 period.Methods; Relying on a health impact assessment framework, we quantified the health benefits of increased walking, cycling and E-biking projected in the negaWatt scenario. The negaWatt scenario assumes increases of walking and cycling volumes of +11% and +612%, respectively, over the study period.Results: As compared to a scenario with no increase in volume of active travel, we quantified that the negaWatt scenario would prevent 9,797 annual premature deaths in 2045 and translate into a 3-month increase in life expectancy in the general population. These health gains would generate €34 billion of economic benefits from 2045 onwards.Conclusion: Increased physical activity implied in the negaWatt transition scenario would generate substantial public health benefits, which are comparable to the gain expected by large scale health prevention interventions.

Journal article

Negev M, Zea-Reyes L, Caputo L, Weinmayr G, Potter C, de Nazelle Aet al., 2022, Barriers and enablers for integrating public health cobenefits in urban climate policy, Annual Review of Public Health, Vol: 43, Pages: 255-270, ISSN: 0163-7525

Urban climate policy offers a significant opportunity to promote improved public health. The evidence around climate and health cobenefits is growing but has yet to translate into widespread integrated policies. This article presents two systematic reviews: first, looking at quantified cobenefits of urban climate policies, where transportation, land use, and buildings emerge as the most studied sectors; and second, looking at review papers exploring the barriers and enablers for integrating these health cobenefits into urban policies. The latter reveals wide agreement concerning the need to improve the evidence base for cobenefits and consensus about the need for greater political will and leadership on this issue. Systems thinking may offer a way forward to help embrace complexity and integrate health cobenefits into decision making. Knowledge coproduction to bring stakeholders together and advance policy-relevant research for urban health will also be required. Action is needed to bring these two important policy agendas together.

Journal article

Goel R, Goodman A, Aldred R, Nakamura R, Tatah L, Garcia LMT, Diomedi-Zapata B, de Sa TH, Tiwari G, de Nazelle A, Tainio M, Buehler R, Gotschi T, Woodcock Jet al., 2022, Cycling behaviour in 17 countries across 6 continents: levels of cycling, who cycles, for what purpose, and how far?, Transport Reviews, Vol: 42, Pages: 58-81, ISSN: 0144-1647

International comparisons of cycling behaviour have typically been limited to high-income countries and often limited to the prevalence of cycling, with lack of discussions on demographic and trip characteristics. We used a combination of city, regional, and national travel surveys from 17 countries across the six continents, ranging from years 2009 through 2019. We present a descriptive analysis of cycling behaviour including level of cycling, trip purpose and distance, and user demographics, at the city-level for 35 major cities (>1 million population) and in urbanised areas nationwide for 11 countries. The Netherlands, Japan and Germany are among the highest cycling countries and their cities among the highest cycling cities. In cities and countries with high cycling levels, cycling rates tend to be more equal between work and non-work trips, whereas in geographies with low cycling levels, cycling to work is higher than cycling for other trips. In terms of cycling distance, patterns in high- and low-cycling geographies are more similar. We found a strong positive association between the level of cycling and women’s representation among cyclists. In almost all geographies with cycling mode share greater than 7% women made as many cycle trips as men, and sometimes even greater. The share of cycling trips by women is much lower in geographies with cycling mode shares less than 7%. Among the geographies with higher levels of cycling, children (<16 years) are often overrepresented. Older adults (>60 years) remain underrepresented in all geographies but have relatively better representation where levels of cycling are high. In low-cycling settings, females are underrepresented across all the age groups, and more so when older than 16 years. With increasing level of cycling, representation of females improves across all the age groups, and most significantly among children and older adults. Clustering the cities and countries into homogeneous cycling typo

Journal article

Nieuwenhuijsen MJ, Barrera-Gomez J, Basagana X, Cirach M, Daher C, Pulido MF, Iungman T, Gasparrini A, Hoek G, de Hoogh K, Khomenko S, Khreis H, de Nazelle A, Ramos A, Rojas-Rueda D, Barboza EP, Tainio M, Thondoo M, Tonne C, Woodcock J, Mueller Net al., 2022, Study protocol of the European Urban Burden of Disease Project: a health impact assessment study, BMJ Open, Vol: 12, Pages: 1-8, ISSN: 2044-6055

Introduction Cities have long been known to be society’s predominant engine of innovation and wealth creation, yet they are also hotspots of pollution and disease partly due to current urban and transport practices. The aim of the European Urban Burden of Disease project is to evaluate the health burden and its determinants related to current and future potential urban and transport planning practices and related exposures in European cities and make this evidence available for policy and decision making for healthy and sustainable futures.Methods and analysis Drawing on an established comparative risk assessment methodology (ie, Urban and Transport Planning Health Impact Assessment) tool), in nearly 1000 European cities we will (1) quantify the health impacts of current urban and transport planning related exposures (eg, air pollution, noise, excess heat, lack of green space) (2) and evaluate the relationship between current levels of exposure, health impacts and city characteristics (eg, size, density, design, mobility) (3) rank and compare the cities based on exposure levels and the health impacts, (4) in a number of selected cities assess in-depth the linkages between urban and transport planning, environment, physical activity and health, and model the health impacts of alternative and realistic urban and transport planning scenarios, and, finally, (5) construct a healthy city index and set up an effective knowledge translation hub to generate impact in society and policy.Ethics and dissemination All data to be used in the project are publicly available data and do not need ethics approval. We will request consent for personal data on opinions and views and create data agreements for those providing information on current and future urban and transport planning scenarios.For dissemination and to generate impact, we will create a knowledge translation hub with information tailored to various stakeholders.

Journal article

de Nazelle A, Roscoe CJ, Roca-Barcelo A, Sebag G, Weinmayr G, Dora C, Ebi KL, Nieuwenhuijsen MJ, Negev Met al., 2021, Urban climate policy and action through a health lens-an untapped opportunity, International Journal of Environmental Research and Public Health, Vol: 18, Pages: 1-9, ISSN: 1660-4601

Motivated by a growing recognition of the climate emergency, reflected in the 26th Conference of the Parties (COP26), we outline untapped opportunities to improve health through ambitious climate actions in cities. Health is a primary reason for climate action yet is rarely integrated in urban climate plans as a policy goal. This is a missed opportunity to create sustainable alliances across sectors and groups, to engage a broad set of stakeholders, and to develop structural health promotion. In this statement, we first briefly review the literature on health co-benefits of urban climate change strategies and make the case for health-promoting climate action; we then describe barriers to integrating health in climate action. We found that the evidence-base is often insufficiently policy-relevant to be impactful. Research rarely integrates the complexity of real-world systems, including multiple and dynamic impacts of strategies, and consideration of how decision-making processes contend with competing interests and short-term electoral cycles. Due to siloed-thinking and restrictive funding opportunities, research often falls short of the type of evidence that would be most useful for decision-making, and research outputs can be cryptic to decision makers. As a way forward, we urge researchers and stakeholders to engage in co-production and systems thinking approaches. Partnering across sectors and disciplines is urgently needed so pathways to climate change mitigation and adaptation fully embrace their health-promoting potential and engage society towards the huge transformations needed. This commentary is endorsed by the International Society for Environmental Epidemiology (ISEE) and the International Society for Urban Health (ISUH) and accompanies a sister statement oriented towards stakeholders (published on the societies’ websites).

Journal article

Jackson C, Johnson R, de Nazelle A, Goel R, de Sá TH, Tainio M, Woodcock Jet al., 2021, A guide to value of information methods for prioritising research in health impact modelling, Epidemiologic Methods, Vol: 10, Pages: 1-22, ISSN: 2194-9263

Health impact simulation models are used to predict how a proposed policy or scenario will affect population health outcomes. These models represent the typically-complex systems that describe how the scenarios affect exposures to risk factors for disease or injury (e.g. air pollution or physical inactivity), and how these risk factors are related to measures of population health (e.g. expected survival). These models are informed by multiple sources of data, and are subject to multiple sources of uncertainty. We want to describe which sources of uncertainty contribute most to uncertainty about the estimate or decision arising from the model. Furthermore, we want to decide where further research should be focused to obtain further data to reduce this uncertainty, and what form that research might take. This article presents a tutorial in the use of Value of Information methods for uncertainty analysis and research prioritisation in health impact simulation models. These methods are based on Bayesian decision-theoretic principles, and quantify the expected benefits from further information of different kinds. The expected value of partial perfect information about a parameter measures sensitivity of a decision or estimate to uncertainty about that parameter. The expected value of sample information represents the expected benefit from a specific proposed study to get better information about the parameter. The methods are applicable both to situations where the model is used to make a decision between alternative policies, and situations where the model is simply used to estimate a quantity (such as expected gains in survival under a scenario). This paper explains how to calculate and interpret the expected value of information in the context of a simple model describing the health impacts of air pollution from motorised transport. We provide a general-purpose R package and full code to reproduce the example analyses.

Journal article

Yang X, McCoy E, Anaya-Boig E, Avila-Palencia I, Brand C, Carrasco-Turigas G, Dons E, Gerike R, Goetschi T, Nieuwenhuijsen M, Orjuela JP, Int Panis L, Standaert A, de Nazelle Aet al., 2021, The effects of traveling in different transport modes on Galvanic Skin Response (GSR) as a measure of stress: an observational study, Environment International, Vol: 156, Pages: 1-10, ISSN: 0160-4120

BackgroundStress is one of many ailments associated with urban living, with daily travel a potential major source. Active travel, nevertheless, has been associated with lower levels of stress compared to other modes. Earlier work has relied on self-reported measures of stress, and on study designs that limit our ability to establish causation.ObjectivesTo evaluate effects of daily travel in different modes on an objective proxy measure of stress, the galvanic skin response (GSR).MethodsWe collected data from 122 participants across 3 European cities as part of the Physical Activity through Sustainable Transport Approaches (PASTA) study, including: GSR measured every minute alongside confounders (physical activity, near-body temperature) during three separate weeks covering 3 seasons; sociodemographic and travel information through questionnaires. Causal relationships between travel in different modes (the “treatment”) and stress were established by using a propensity score matching (PSM) approach to adjust for potential confounding and estimating linear mixed models (LMM) with individuals as random effects to account for repeated measurements. In three separate analyses, we compared GSR while cycling to not cycling, then walking to not walking then motorized (public or private) travel to any activity other than motorized travel.ResultsDepending on LMM formulations used, cycling reduces 1-minute GSR by 5.7% [95% CI: 2.0–16.9%] to 11.1% [95% CI: 5.0–24.4%] compared to any other activity. Repeating the analysis for other modes we find that: walking is also beneficial, reducing GSR by 3.9% [95% CI: 1.4–10.7%] to 5.7% [95% CI: 2.6–12.3%] compared to any other activity; motorized mode (private or public) in reverse increases GSR by up to 1.1% [95% CI: 0.5–2.9%].DiscussionActive travel offers a welcome way to reduce stress in urban dwellers’ daily lives. Stress can be added to the growing number of evidence-based reasons for

Journal article

Siriaporn N, de Nazelle A, Maignant G, Staccini P, Vuillemin Aet al., 2021, Usage of Mobile Apps to support Active Transportation: Scoping Review (Preprint)

<sec> <title>BACKGROUND</title> <p>The World Health Organization recommends 150-300 minutes of physical activity per week to lower health risks caused by sedentary behavior. Incorporating active transport (AT), non-motorized methods of transportation like walking and cycling, into daily life is an efficient way for individuals to reach recommended levels of physical activity. Active transportation can also improve the environment by reducing pollution emission when people make a switch from personal motorized vehicles. Smartphones have been explored as a tool to deliver health interventions through mobile apps, especially in the field of behavior change in weight loss and physical activity.</p> </sec> <sec> <title>OBJECTIVE</title> <p>This study sought to explore the extent of the usage of mobile apps in the field of active transport, both academically and commercially. We want to know if and how much mobile apps are being used in active transport research, as well as its availability commercially. This will allow us to realize the current trends and gaps of the field.</p> </sec> <sec> <title>METHODS</title> <p>A search on academic literature and commercial apps for any apps that support active transportation was done in five academic databases and the two app stores. For a wide check, commercial apps were searched in six countries, one in each continent. Two of the authors reviewed the articles and apps for inclusion and another made the final decision if conflict arose.</p> </sec> <sec> <title>RESULTS</title> <p>In academic literature

Journal article

, 2021, A conversation on the impacts and mitigation of air pollution., Nat Commun, Vol: 12

Air pollution is an environmental and health concern affecting millions globally every day. Dr Audrey de Nazelle, an expert in air pollution risk assessment and exposure science at Imperial College London, shares with Nature Communications their thoughts on the impacts of air pollution and the policies needed to tackle emissions.

Journal article

Yang Z, He Z, Zhang K, Zeng L, de Nazelle Aet al., 2021, Investigation into Beijing commuters' exposure to ultrafine particles in four transportation modes: bus, car, bicycle and subway, ATMOSPHERIC ENVIRONMENT, Vol: 266, ISSN: 1352-2310

Journal article

Riley R, de Preux L, Capella P, Mejia C, Kajikawa Y, de Nazelle Aet al., 2021, How do we effectively communicate air pollution to change public attitudes and behaviours? A review, Sustainability Science, Vol: 16, Pages: 2027-2047, ISSN: 1862-4065

Solutions that engage the public are needed to tackle air pollution. Technological approaches are insufficient to bring urban air quality to recommended target levels, and miss out on opportunities to promote health more holistically through behavioural solutions, such as active travel. Behaviour change is not straightforward, however, and is more likely to be achieved when communication campaigns are based on established theory and evidence-based practices. We systematically reviewed the academic literature on air pollution communication campaigns aimed at influencing air pollution-related behaviour. Based on these findings, we developed an evidence-based framework for stimulating behaviour change through engagement. Across the 37 studies selected for analyses, we identified 28 different behaviours assessed using a variety of designs including natural and research-manipulated experiments, cross-sectional and longitudinal surveys and focus groups. While avoidance behaviour (e.g. reducing outdoor activity) followed by contributing behaviours (e.g. reducing idling) were by far the most commonly studied, supporting behaviour (e.g. civil engagement) shows promising results, with the added benefit that supporting local and national policies may eventually lead to the removal of social and physical barriers that prevent wider behavioural changes. Providing a range of actionable information will reduce disengagement due to feelings of powerlessness. Targeted localized information will appear more immediate and engaging, and positive framing will prevent cognitive dissonance whereby people rationalize their behaviour to avoid living with feelings of unease. Communicating the co-benefits of action may persuade individuals with different drivers but as an effective solution, it remains to be explored. Generally, finding ways to connect with people’s emotions, including activating social norms and identities and creating a sense of collective responsibility, provide prom

Journal article

Hoffmann B, Boogaard H, de Nazelle A, Andersen ZJ, Abramson M, Brauer M, Brunekreef B, Forastiere F, Huang W, Kan H, Kaufman JD, Katsouyanni K, Krzyzanowski M, Kuenzli N, Laden F, Nieuwenhuijsen M, Mustapha A, Powell P, Rice M, Roca-Barcelo A, Roscoe CJ, Soares A, Straif K, Thurston Get al., 2021, WHO Air Quality Guidelines 2021-aiming for healthier air for all: a joint statement by medical, public health, scientific societies and patient representative organisations, International Journal of Public Health, Vol: 66, ISSN: 1661-8564

Journal article

Laumbach RJ, Cromar KR, Adamkiewicz G, Carlsten C, Charpin D, Chan WR, de Nazelle A, Forastiere F, Goldstein J, Gumy S, Hallman WK, Jerrett M, Kipen HM, Pirozzi CS, Polivka BJ, Radbel J, Shaffer RE, Sin DD, Viegi Get al., 2021, Personal interventions for reducing exposure and risk for outdoor air pollution, Annals of the American Thoracic Society, Vol: 18, Pages: 1435-1443, ISSN: 1546-3222

Poor air quality affects the health and wellbeing of large populations around the globe. Although source controls are the most effective approaches for improving air quality and reducing health risks, individuals can also take actions to reduce their personal exposure by staying indoors, reducing physical activity, altering modes of transportation, filtering indoor air, and using respirators and other types of face masks. A synthesis of available evidence on the efficacy, effectiveness, and potential adverse effects or unintended consequences of personal interventions for air pollution is needed by clinicians to assist patients and the public in making informed decisions about use of these interventions. To address this need, the American Thoracic Society convened a workshop in May of 2018 to bring together a multidisciplinary group of international experts to review the current state of knowledge about personal interventions for air pollution and important considerations when helping patients and the general public to make decisions about how best to protect themselves. From these discussions, recommendations were made regarding when, where, how, and for whom to consider personal interventions. In addition to the efficacy and safety of the various interventions, the committee considered evidence regarding the identification of patients at greatest risk, the reliability of air quality indices, the communication challenges, and the ethical and equity considerations that arise when discussing personal interventions to reduce exposure and risk from outdoor air pollution.

Journal article

Nieuwenhuijsen M, Fletcher T, de Nazelle A, Etzel RAet al., 2021, Re: Sponsorship by Big Oil, Like the Tobacco Industry, Should be Banned by the Research Community, EPIDEMIOLOGY, Vol: 32, Pages: E11-E11, ISSN: 1044-3983

Journal article

Brand C, Dons E, Anaya-Boig E, Avila-Palencia I, Clark A, de Nazelle A, Gascon M, Gaupp-Berghausen M, Gerike R, Gotschi T, Iacorossi F, Kahlmeier S, Laeremans M, Nieuwenhuijsen MJ, Orjuela JP, Racioppi F, Raser E, Rojas-Rueda D, Standaert A, Stigell E, Sulikova S, Wegener S, Panis LIet al., 2021, The climate change mitigation effects of daily active travel in cities, Transportation Research Part D: Transport and Environment, Vol: 93, Pages: 1-18, ISSN: 1361-9209

Active travel (walking or cycling for transport) is considered the most sustainable form of personal transport. Yet its net effects on mobility-related CO2 emissions are complex and under-researched. Here we collected travel activity data in seven European cities and derived life cycle CO2 emissions across modes and purposes. Daily mobility-related life cycle CO2 emissions were 3.2 kgCO2 per person, with car travel contributing 70% and cycling 1%. Cyclists had 84% lower life cycle CO2 emissions than non-cyclists. Life cycle CO2 emissions decreased by −14% per additional cycling trip and decreased by −62% for each avoided car trip. An average person who ‘shifted travel modes’ from car to bike decreased life cycle CO2 emissions by 3.2 kgCO2/day. Promoting active travel should be a cornerstone of strategies to meet net zero carbon targets, particularly in urban areas, while also improving public health and quality of urban life.

Journal article

Brand C, Gotschi T, Dons E, Gerike R, Anaya-Boig E, Avila-Palencia I, de Nazelle A, Gascon M, Gaupp-Berghausen M, Iacorossi F, Kahlmeier S, Panis LI, Racioppi F, Rojas-Rueda D, Standaert A, Stigell E, Sulikova S, Wegener S, Nieuwenhuijsen MJet al., 2021, The climate change mitigation impacts of active travel: Evidence from a longitudinal panel study in seven European cities, GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS, Vol: 67, Pages: 1-15, ISSN: 0959-3780

Active travel (walking or cycling for transport) is considered the most sustainable and low carbon form of getting from A to B. Yet the net effects of changes in active travel on changes in mobility-related CO2 emissions are complex and under-researched. Here we collected longitudinal data on daily travel behavior, journey purpose, as well as personal and geospatial characteristics in seven European cities and derived mobility-related lifecycle CO2 emissions over time and space. Statistical modelling of longitudinal panel (n = 1849) data was performed to assess how changes in active travel, the ‘main mode’ of daily travel, and cycling frequency influenced changes in mobility-related lifecycle CO2 emissions.We found that changes in active travel have significant lifecycle carbon emissions benefits, even in European urban contexts with already high walking and cycling shares. An increase in cycling or walking consistently and independently decreased mobility-related lifecycle CO2 emissions, suggesting that active travel substituted for motorized travel – i.e. the increase was not just additional (induced) travel over and above motorized travel. To illustrate this, an average person cycling 1 trip/day more and driving 1 trip/day less for 200 days a year would decrease mobility-related lifecycle CO2 emissions by about 0.5 tonnes over a year, representing a substantial share of average per capita CO2 emissions from transport. The largest benefits from shifts from car to active travel were for business purposes, followed by social and recreational trips, and commuting to work or place of education. Changes to commuting emissions were more pronounced for those who were younger, lived closer to work and further to a public transport station.Even if not all car trips could be substituted by active travel the potential for decreasing emissions is considerable and significant. The study gives policy and practice the empirical evidence needed to assess climate

Journal article

Kahlmeier S, Boig EA, Castro A, Smeds E, Benvenuti F, Eriksson U, Iacorossi F, Nieuwenhuijsen MJ, Panis LI, Rojas-Rueda D, Wegener S, de Nazelle Aet al., 2021, Assessing the policy environment for active mobility in cities-development and feasibility of the PASTA cycling and walking policy environment score, International Journal of Environmental Research and Public Health, Vol: 18, Pages: 1-13, ISSN: 1660-4601

The importance of setting a policy focus on promoting cycling and walking as sustainable and healthy modes of transport is increasingly recognized. However, to date a science-driven scoring system to assess the policy environment for cycling and walking is lacking. In this study, spreadsheet-based scoring systems for cycling and walking were developed, including six dimensions (cycling/walking culture, social acceptance, perception of traffic safety, advocacy, politics and urban planning). Feasibility was tested using qualitative data from pre-specified sections of semi-standardized interview and workshop reports from a European research project in seven cities, assessed independently by two experts. Disagreements were resolved by discussions of no more than 75 minutes per city. On the dimension “perception of traffic safety”, quantitative panel data were used. While the interrater agreement was fair, feasibility was confirmed in general. Validity testing against social norms towards active travel, modal split and network length was encouraging for the policy area of cycling. Rating the policy friendliness for cycling and walking separately was found to be appropriate, as different cities received the highest scores for each. Replicating this approach in a more standardized way would pave the way towards a transparent, evidence-based system for benchmarking policy approaches of cities towards cycling and walking.

Journal article

Tainio M, Andersen ZJ, Nieuwenhuijsen MJ, Hu L, de Nazelle A, An R, Garcia LMT, Goenka S, Zapata-Diomedi B, Bull F, de Sa THet al., 2021, Air pollution, physical activity and health: A mapping review of the evidence, ENVIRONMENT INTERNATIONAL, Vol: 147, ISSN: 0160-4120

Journal article

Corada K, Woodward H, Alaraj H, Collins CM, de Nazelle Aet al., 2021, A systematic review of the leaf traits considered to contribute to removal of airborne particulate matter pollution in urban areas, Environmental Pollution, Vol: 269, Pages: 1-13, ISSN: 0269-7491

Global urban planning has promoted green infrastructure (GI) such as street trees, shrubs or other greenspace in order to mitigate air pollution. Although considerable attention has been paid to understanding particulate matter (PM) deposition on GI, there has been little focus on identifying which leaf traits might maximise airborne PM removal. This paper examines existing literature to synthesize the state of knowledge on leaf traits most relevant to PM removal. We systematically reviewed measurement studies that evaluated particulate matter accumulated on leaves on street trees, shrubs green roofs, and green walls, for a variety of leaf traits. Our final selection included 62 papers, most from field studies and a handful from wind tunnel studies. The following were variously promoted as useful traits: coniferous needle leaves; small, rough and textured broadleaves; lanceolate and ovate shapes; waxy coatings, and high-density trichomes. Consideration of these leaf traits, many of which are also associated with drought tolerance, may help to maximise PM capture. Although effective leaf traits were identified, there is no strong or consistent evidence to identify which is the most influential leaf trait in capturing PM. The diversity in sampling methods, wide comparison groups and lack of background PM concentration measures in many studies limited our ability to synthesize results. We found that several ancillary factors contribute to variations in the accumulation of PM on leaves, thus cannot recommend that selection of urban planting species be based primarily on leaf traits. Further research into the vegetation structural features and standardization of the method to measure PM on leaves is needed.

Journal article

Gascon M, Marquet O, Gràcia-Lavedan E, Ambròs A, Götschi T, Nazelle AD, Panis LI, Gerike R, Brand C, Dons E, Eriksson U, Iacorossi F, Ávila-Palència I, Cole-Hunter T, Nieuwenhuisjen MJet al., 2020, What explains public transport use? Evidence from seven European cities, Transport Policy, Vol: 99, Pages: 362-374, ISSN: 0967-070X

Backgroundthe relationships between the built environment characteristics and personal factors influencing public transport use and the ways they interact are not well understood.Objectivewe aim to advance the understanding of the relationship between built environment and frequency of public transport use in seven European cities, while accounting for other factors, such as individual values and attitudes.Methodsin this population-based cross-sectional study, we collected information on mobility behaviour including frequency of public transport use, individual characteristics, and attitudes towards transport, environment and health issues (N = 9952). Home and work/study built environment characteristics were determined with GIS-based techniques. We also applied factor and principal component analyses to define profiles of potential correlates. Logistic regression analyses for each frequency category of public transport use (1–3 days/month, 1–3 days/week, and daily or almost daily), using as reference “never or less than once a month”, were applied. City was included as random effect.ResultsOver all, a large percentage of participants reported daily or almost daily public transport use for travel (40.5%), with a wide range across cities (from 7.1% in Örebro to 59.8% in Zurich). Being female, highly educated, a student, or not working increased the odds of higher frequency of using public transport, while having access to a car and/or a bike reduced the odds. Living or working in high-density areas was associated with higher frequency of public transport use, while living or working in low-density areas was associated with lower frequency (1–3 days/month or 1–3 days/week). We observed interactions between built environment characteristics and having access to a car and/or a bike. For instance, greater distance between the residential and the work or study address increased the odds of higher frequency of public transport use

Journal article

Cruz-Piedrahita C, Howe C, de Nazelle A, 2020, Public health benefits from urban horticulture in the global north: A scoping review and framework, Global Transitions, Vol: 2, Pages: 246-256, ISSN: 2589-7918

Urban agriculture has increased rapidly in the Global North in recent decades. However, because most research has focused on developing countries, we still lack systematic information on the benefits, barriers, costs and risks of the practice of food production in cities of the Global North. Urban horticulture (UH) is the agriculture of plants for food consumption, materials production, or decoration, developed inside city boundaries. UH has recently been proposed as a tool to improve population health and urban biodiversity. This study takes a systems approach to reviewing the literature on the impacts of UH on public health, the environment and health behaviours, using the ecosystem services (ES) concept as lens. Using a scoping review methodology, 138 papers met the search criteria and these studies were used to develop a conceptual framework summarizing and synthesing the direct and indirect pathways in which urban horticulture and public health are interconnected. The resulting “eco”systems-based framework analyses and visualises the relationship between UH and public health and provides evidence for relationships (both positive and negative) between, and pathways linking, urban horticulture and benefits for mental health, physical activity, diet, and socialisation. This study demonstrates that UH can help to improve public health in cities of the Global North and makes the case for UH as a solution to tackling multiple health and societal challenges that arise in urban populations. We provide a framework to enable local authorities and urban stakeholders to maximise the benefits from, and reduce the risks related to, the practice of UH at a systems level.

Journal article

Heydari S, Tainio M, Woodcock J, de Nazelle Aet al., 2020, Estimating traffic contribution to particulate matter concentration in urban areas using a multilevel Bayesian meta-regression approach, Environment International, Vol: 141, Pages: 1-8, ISSN: 0160-4120

Quantifying traffic contribution to air pollution in urban settings is required to inform traffic management strategies and environmental policies that aim at improving air quality. Assessments and comparative analyses across multiple urban areas are challenged by the lack of datasets and methods available for global applications. In this study, we quantify the traffic contribution to particulate matter concentration in multiple cities worldwide by synthesising 155 previous studies reported in the World Health Organization (WHO)’s air pollution source apportionment data for PM10 and PM2.5. We employed a Bayesian multilevel meta-regression that accounts for uncertainties and captures both within- and between-study variations (in estimation methods, study protocols, etc.) through study-specific and location-specific explanatory variables. The final sample analysed in this paper covers 169 cities worldwide. Based on our analysis, traffic contribution to air pollution (particulate matter) varies from 5% to 61% in cities worldwide, with an average of 27%. We found that variability in the traffic contribution estimates reported worldwide can be explained by the region of study, publication year, PM size fraction, and population. Specifically, traffic contribution to air pollution in cities located in Europe, North America, or Oceania is on average 36% lower relative to the rest of the world. Traffic contribution is 28% lower among studies published after 2005 than those published on or before 2005. Traffic contribution is on average 24% lower among cities with less than 500,000 inhabitants and 19% higher when estimated based on PM10 relative to PM2.5. This quantitative summary overcomes challenges in the data and provides useful information for health impact modellers and decision-makers to assess impacts of traffic reduction policies.

Journal article

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00749077&limit=30&person=true