Method Suggestion of Predicting the Exposure to Residential Indoor Air Pollutants Using Time-Activity Patterns and Outdoor Air

摘要

Most people may be affected by indoor air quality at home since it is where they spend most of their time. Although air pollutants (APs) concentrations such as particulate matter, SO2, NO2, CO, and O3 is provided through ambient fixed monitoring system, it could be different from actual exposure concentrations because it has limitations such as distance and staying in indoor environments. The purposes of this study were to predict the concentrations of Indoor APs (lAPs) and to assess exposures at home considering indoor sources and house residential time of people by analyzing time-activity patterns including questionnaire. To estimate lAPs concentrations, we applied the concentration of outdoor air pollutants by measurements or atmospheric modelling, and indoor air quality model to PM, NO2, CO concentrations with indoor sources, and Indoor/Outdoor ratio acquired from previous studies, and to SO2 and O3 concentrations without indoor sources. The concentrations of APs were acquired from ambient fixed monitoring system. And the concentrations of lAPs were measured in houses with sensor instruments of particulate matter by adjusting gravimetric method, and exposure to lAPs were estimated. Residential time at home was more than about 90% their times. Results of measurements of sensor indicate increased concentrations of lAPs with indoor sources from cooking, cleaning and smoking than usual (no behavior) and concentrations of lAPs with indoor sources increase as number of the behavior increase. Sub-populations such as the old and housewives might be more likely to be affected by house indoor air because they spend most of their time at home. We predicted the concentrations of lAPs and assessed exposures at home to lAPs by modelling and analyzing time-activity patterns including questionnaire. These results will be expected to provide basis for preparing guidelines for prevention of diseases caused by house lAPs