생활시간조사 자료를 활용한 인구집단별 국소환경 초미세먼지(PM2.5) 노출 및 기여율 평가

Assessing PM2.5 Exposure and Contribution Rates by Cluster Microenvironments via a Time-Use Survey

Background: People spend 80~90% of their day indoors, with only 10~20% of their time spent outdoors. Evaluating exposure accurately requires assessments based on an individual’s time-activity pattern. Objectives: The purpose of this study is to evaluate the exposure and contribution rates of PM2.5 by microenvironment, identify related exposure factors, and suggest management measures and priorities. Methods: This study analyzed the time-activity patterns of 3,984 weekday respondents in Seoul using data from the 2014 Time-Use Survey by Statistics Korea. The respondents were clustered, and occupational groups were estimated by conducting a frequency analysis of sociodemographic factors. Location data was collected at 10-minute intervals, followed by exposure scenario construction and active simulations. When calculating the exposure and contribution rates of PM2.5, the Korean exposure factors handbook was used to account for inhalation rates. Results: Most of the indoor microenvironments where people spend their time are residential. Students spend the most time indoors at 22.7 hours per day, followed by senior citizens at 22.5 hours, office workers at 22.0 hours, and stay-at-home parents at 21.8 hours. Although people spend little time in spaces such as outdoors, in transportation, and other indoor microenvironments, higher PM2.5 concentrations significantly increase the contribution rates. Among all clusters, even though cluster 10 (office workers) and cluster 2 (night security workers) spend relatively little time in other indoor microenvironments, such as Korean barbecue restaurants and pubs, they were included in the scenarios, resulting in higher exposure concentrations and contribution rates. Conclusions: The analysis of PM2.5 exposure contribution rates by microenvironment revealed that the highest exposure occurred in the ‘other indoor’ category, with Korean barbecue restaurants showing the highest concentration levels among them. Based on the PM2.5 exposure contribution rates in the microenvironments, this study suggests priority locations and population groups for targeted management.