Journal of Environmental Protection, 2017, 8, 1372-1392 http://www.scirp.org/journal/jep ISSN Online: 2152-2219 ISSN Print: 2152-2197 DOI: 10.4236/jep.2017.811084 Oct. 31, 2017 1372 Journal of Environmental Protection Traffic Maps and Smartphone Trajectories to Model Air Pollution, Exposure and Health Impact Erik Skjetne 1 , Hai-Ying Liu 2* 1 Non-Affiliated, Rælingen, Norway 2 NILU—Department of Environmental Impacts and Sustainability, Norwegian Institute for Air Research, Kjeller, Norway Abstract In this study, we explored to combine traffic maps and smartphone trajecto- ries to model traffic air pollution, exposure and health impact. The approach was step-by-step modeling through the causal chain: engine emission, traffic density versus traffic velocity, traffic pollution concentration, exposure along individual trajectories, and health risk. A generic street with 100 km/h speed limit was used as an example to test the model. A single fixed-time trajectory had maximum exposure at velocity of 45 km/h at maximum pollution con- centration. The street population had maximum exposure shifted to a velocity of 15 km/h due to the congestion density of vehicles. The shift is a universal ef- fect of exposure. In this approach, nearly every modeling step of traffic pollution depended on traffic velocity. A traffic map is a super-efficient pre-processor for calculating real-time traffic pollution exposure at global scale using big data analytics. Keywords Traffic Map, Smartphone, Location Service, Trajectory, Traffic Pollution, Public Health, Road Traffic Exposure, Analytics, Big Data 1. Introduction Traffic pollution is the dominant source of air pollution in most metropolitan areas and has major health effects. 50% of the world’s population lives in urban areas covering only 0.4% of the earth’s surface, and 70% are projected to live in urban areas by 2050 [1]. In many European cities, industrial air pollution is be- ing replaced by traffic pollution [2]. For example in Moscow, traffic pollution How to cite this paper: Skjetne, E. and Liu, H.-Y. (2017) Traffic Maps and Smart- phone Trajectories to Model Air Pollution, Exposure and Health Impact. Journal of Environmental Protection, 8, 1372-1392. https://doi.org/10.4236/jep.2017.811084 Received: September 22, 2017 Accepted: October 28, 2017 Published: October 31, 2017 Copyright © 2017 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access