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A GIS decision-support analysis of exposure to air pollution during active travel in Leicester

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Air pollution exposure has been recognised as one of the leading concerns for adverse health impacts in urban environments. While active transportation has the potential to be a sustainable solution in addressing health concerns, individuals shifting to active transportation may be at risk of intensifying their spatial exposure. The investigation deals with Leicester, East Midlands, a city that has launched several active transportation initiatives to help meet national air quality targets. This dissertation undertakes a decision-support analysis of the spatial exposures to air pollution during active transportation, with a primary focus on walkability and cyclability. Exposure estimates for active and motorised transportation were generated through the employment of network analysis alongside ModelBuilder scripts within a GIS. The results demonstrate that active transportation is a viable option for reducing spatial exposures to air pollution. Commuters who make the shift from motorised to active transportation can reduce their mean exposure to NO₂ by 4.94 % during walking trips made within 2 km and by 8.43 % during cycling trips made within 5 km. In comparison to trips made by motorised transportation, commuters reduce their spatial exposures by travelling along dedicated walking and cycling routes that separate the commuter from direct vehicular emissions. Inconsistencies in exposure change during walking trips made to central Leicester can be explained by the limited accessibility and provision of lower exposure routes within urban hotspots. The contribution of this dissertation advances understandings current understandings in traffic-related exposures in the light of future health impact assessments.
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