Urban and Transport Planning Related Exposures and Mortality: A Health Impact Assessment for Cities

Abstract

Background: By 2050, nearly 70% of the global population is projected to live in urban areas. Because the environments we inhabit affect our health, urban and transport designs that promote healthy living are needed.

Objective: We estimated the number of premature deaths preventable under compliance with international exposure recommendations for physical activity (PA), air pollution, noise, heat, and access to green spaces.

Methods: We developed and applied the Urban and TranspOrt Planning Health Impact Assessment (UTOPHIA) tool to Barcelona, Spain. Exposure estimates and mortality data were available for 1,357,361 residents. We compared recommended with current exposure levels. We quantified the associations between exposures and mortality and calculated population attributable fractions to estimate the number of premature deaths preventable. We also modeled life-expectancy and economic impacts.

Results: We estimated that annually, nearly 20% of mortality could be prevented if international recommendations for performance of PA; exposure to air pollution, noise, and heat; and access to green space were followed. Estimations showed that the greatest portion of preventable deaths was attributable to increases in PA, followed by reductions of exposure to air pollution, traffic noise, and heat. Access to green spaces had smaller effects on mortality. Compliance was estimated to increase the average life expectancy by 360 (95% CI: 219, 493) days and result in economic savings of 9.3 (95% CI: 4.9, 13.2) billion EUR/year.

Conclusions: PA factors and environmental exposures can be modified by changes in urban and transport planning. We emphasize the need for a) the reduction of motorized traffic through the promotion of active and public transport and b) the provision of green infrastructure, both of which are suggested to provide opportunities for PA and for mitigation of air pollution, noise, and heat. Citation: Mueller N, Rojas-Rueda D, Basagaña X, Cirach M, Cole-Hunter T, Dadvand P, Donaire-Gonzalez D, Foraster M, Gascon M, Martinez D, Tonne C, Triguero-Mas M, Valentín A, Nieuwenhuijsen M. 2017. Urban and transport planning related exposures and mortality: a health impact assessment for cities. Environ Health Perspect 125:89-96; http://dx.doi.org/10.1289/EHP220.

Figure 1

Conceptual framework of the Urban and TranspOrt Planning Health Impact Assessment (UTOPHIA) tool. (1) Recommended exposure level; (2) current exposure level; (3) exposure difference between recommended and current exposure level; (4) exposure response function (ERF) quantifying association between exposure and mortality; (5) relative risk (RR) corresponding to exposure difference; (6) population attributable fraction (PAF) corresponding to exposure difference.

Figure 2

Environmental exposure maps for Barcelona at the census-tract level (n = 1,061). (A) Air pollution, PM_2.5 annual mean; (B) daytime road traffic noise, L_Aeq,16hr (0700–2300 hours); (C) heat, daily mean temperature for 1 July 2011; (D) green spaces, green space surface in percent (GS%) of green spaces ≥ 0.5 ha. Source: Instituto Nacional de Estadística 2013. Own compilation with data taken from the INE website: www.ine.es. L_Aeq, A-weighted equivalent sound pressure levels in decibels; PM_2.5, particulate matter with a diameter ≤ 2.5 μm.

Figure 3

Estimated preventable deaths under compliance with exposure recommendations by exposure domain. The exposure response functions (ERF) for physical activity, air pollution and green spaces were obtained from meta-analyses. The ERF for noise was taken from an ecological study. The ERF for heat was taken from a population-level time-series study. CI, confidence interval.

Figure 4

Mortality pathways of urban and transport policies. Health effects of urban and transport planning are most likely considered in terms of traffic safety. However, health pathways of physical activity, air pollution, traffic noise, heat, and green spaces show considerable impacts on natural all-cause mortality.