Using smartphones to collect time-activity data for long-term personal-level air pollution exposure assessment

• Published in: Journal of exposure science & environmental epidemiology Vol. 26; no. 4; pp. 356 - 364
• Main Authors: Glasgow, Mark L, Rudra, Carole B, Yoo, Eun-Hye, Demirbas, Murat, Merriman, Joel, Nayak, Pramod, Crabtree-Ide, Christina, Szpiro, Adam A, Rudra, Atri, Wactawski-Wende, Jean, Mu, Lina
• Format: Journal Article
• Language: English
• Published: United States Nature Publishing Group 01.06.2016
• Subjects: Adult; Air pollution; Air Pollution - analysis; Air quality; Comparative analysis; Data collection; Data Collection - methods; Data Collection - standards; Data entry; Diaries; Environmental aspects; Environmental health; Environmental monitoring; Environmental Monitoring - methods; Evaluation; Exposure; Feasibility; Female; Geographic Information Systems; Health aspects; Humans; Male; Methods; Middle Aged; Mobile Applications - standards; Mobile Applications - statistics & numerical data; New York; Pollutants; Self Report; Smart phones; Smartphone; Smartphones; Technology application; Temporal resolution; Time; Time of use; Young Adult; United States
• ISSN: 1559-0631; 1559-064X
• DOI: 10.1038/jes.2014.78

Because of the spatiotemporal variability of people and air pollutants within cities, it is important to account for a person's movements over time when estimating personal air pollution exposure. This study aimed to examine the feasibility of using smartphones to collect personal-level time-activity data. Using Skyhook Wireless's hybrid geolocation module, we developed "Apolux" (Air, Pollution, Exposure), an Android(TM) smartphone application designed to track participants' location in 5-min intervals for 3 months. From 42 participants, we compared Apolux data with contemporaneous data from two self-reported, 24-h time-activity diaries. About three-fourths of measurements were collected within 5 min of each other (mean=74.14%), and 79% of participants reporting constantly powered-on smartphones (n=38) had a daily average data collection frequency of <10 min. Apolux's degree of temporal resolution varied across manufacturers, mobile networks, and the time of day that data collection occurred. The discrepancy between diary points and corresponding Apolux data was 342.3 m (Euclidian distance) and varied across mobile networks. This study's high compliance and feasibility for data collection demonstrates the potential for integrating smartphone-based time-activity data into long-term and large-scale air pollution exposure studies.