Do Individuals’ Activity Structures Influence Their PM₂.₅ Exposure Levels? Evidence from Human Trajectory Data in Wuhan City

• Main Authors: Siyu Ma, Lin Yang, Mei-Po Kwan, Zejun Zuo, Haoyue Qian, Minghao Li
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: PM₂.₅ exposure; human mobility; cell phone GPS dataset; activity patterns; PM₂.₅
• Online Access: https://www.mdpi.com/1660-4601/18/9/4583

Severe air pollution has become a major risk to human health from a global environmental perspective. It has been recognized that human mobility is an essential component in individual exposure assessment. Activity structure reflects the characteristics of human mobility. Thus, a better understanding of the relationship between human activity structure and individual exposure level is of crucial relevance. This study examines this relationship using a large cell-phone GPS dataset in Wuhan, China. The results indicate that there is a strong linear relationship between people’s activity structures and exposures to PM₂.₅. Inter-group comparisons based on the four activity structure groups obtained with K-means clustering found that groups with different activity structures do experience different levels of PM₂.₅ exposure. Furthermore, differences in detailed characteristics of activity structure were also found at different exposure levels at the intra-group level. These results show that people’s activity structures do influence their exposure levels. The paper provides a new perspective for understanding individual exposure through human activity structure, which helps move the perspective of research on individual exposure from the semantic of physical location to the semantic of human activity pattern.