Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school Christina Mitsakou1, Sani Dimitroulopoulou1, Karen Exley1, Clare Heaviside1, Helen Macintyre1, Dimitris Evangelopoulos2, Alison Gowers1, Heather Walton2, Sotiris Vardoulakis1 1Air Pollution and Climate Change Group; Environmental Change Department; Centre for Radiation, Chemical & Environmental Hazards 2Environmental Research Group, Kings College London

http://www.hpru-ech.nihr.ac.uk/theme-2-healthy-sustainable-cities/ http://hieh.hpru.nihr.ac.uk/our-research/research-themes/theme-4-project-7-methods-assessing-public-health-benefits-local

Local transport interventions – the challenge There are particular challenges in assessing the air pollution health impacts of local transport interventions as: (i) the epidemiological studies on which concentration-response functions are based are not necessarily at the fine spatial scale required for assessing the impact of concentration changes at roadsides;

(ii) the population affected may be very small for any individual policy; (iii) health impact assessment of other risk factors may be less well developed than for air pollution; (iv) changes in transport behaviour change personal exposure to air pollution and the links between the broader exposure metrics used in epidemiological studies and personal exposure is poorly understood.

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Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Background – Potential aims The proportion of young children (primary school) walking to school in England has been decreasing.

Source: National travel Survey England 2014

Research questions: - How much do the school trip car journeys affect young children’s health? - What would be the benefits from a school trip modal shift in local air quality and children’s health? Potential funding sources: Defra, DH, DoE, GLA 3

Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Methodological steps – 1 Selection of case studies - Investigate/review the current and past status of local interventions affecting school trips and explore their effectiveness. - Select 2-3 case studies/schools/local areas to test the impact of introducing a modal shift intervention. - Review and select health outcomes that are sufficiently frequent in school children to be examined. 4

Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Methodological steps – 2 Exposure calculations - Emissions: Estimate the emissions released from the school trips (DEFRA emission toolkit);

- Pollutants’ concentrations: Calculate the pollutant concentrations (NO2, PM, O3) in the local environment around schools (OSPM model); - Exposure: Estimate population exposure of “school going children”, considering also the indoor environment (INDAIR/EXPAIR modelling framework).

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Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Methodological steps – 3 Health impact assessment - Assess potential risks/benefits related to:

a) changes in exposure to the pollutant concentrations, b) personal exercise from active travel – walk, cycle

c) occurrence of road accidents (use of WebTag or similar toolkit); 6

Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Final step Integration and recommendations - Scale up to a larger number of schools with different configurations - Provide a set of suggestions for reducing adverse health impacts to young school-going children.

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Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school

Key publications COMEAP (2015), “Quantification of mortality and hospital admissions associated with ground-based ozone”.

Dimitroulopoulou, Ashmore, and Terry, “Use of Population Exposure Frequency Distributions to simulate effects on policy interventions on NO2 exposure”, Atmospheric Environment, accepted. WHO (2016), "Health risk assessment of air pollution - general principles.“ Mueller et al. (2015), "Health impact assessment of active transportation: A systematic review." Preventive Medicine 76: 103-114. Department for Transport, National Travel Survey: England 2014.

Weinmayr et al. (2010), “Short-term effects of PM10 and NO2 on respiratory health among children with asthma or asthma-like symptoms: a systematic review and meta-analysis”, EHP 118: 449-457. WHO Experts (2014), "WHO Expert Meeting: Methods and tools for assessing the health risks of air pollution at local, national and international level." de Nazelle et al (2011), "Improving health through policies that promote active travel: A review of evidence to support integrated health impact assessment." Environment International 37(4): 766777. de Hartog J et al. (2010), "Do the health benefits of cycling outweigh the risks?" Environ Health Perspect 118(8): 1109-1116. Woodcock J et al. (2009), "Public health benefits of strategies to reduce greenhouse-gas emissions: urban land transport." Lancet 374: 1930–1943. 8

Joint HPRU ECH (Theme 2) and HIEH (Theme 4) pilot project – Walking to school