Longitudinal assessment of personal air pollution clouds in ten home and office environments

Elevated exposure to indoor air pollution is associated with negative human health and well-being outcomes. Inhalation exposure studies commonly rely on stationary monitors in combination with human time-activity patterns; however, this method is susceptible to exposure misclassification. We tracked ten participants during five consecutive workdays with stationary air pollutant monitors at their homes and offices, and wearable personal monitors. Real-time measures of size-resolved particulate matter (within range 0.3-10 mu m) and CO2, and integrated samples of PM10, VOCs, and aldehydes were collected. The PM10 cloud magnitude (excess of PM10 beyond stationary room concentration) was detected for all participants in homes and offices. The PM10 cloud magnitude ranged within 5-37 mu g/m(3) and was the most discernible in the coarse particle size fraction. Particles associated with "Urban mix," "Traffic," and "Human activities" sources contributed the most to PM10 exposures. The personal CO2 clouds were detected for participants with the SEMs in their living rooms and private or low-occupancy offices. The stationary monitors placed in bedrooms were better predictors of personal PM10 and CO2 exposures. An overall of 33 VOCs and aldehydes were detected in both microenvironments, with the majority exhibiting high correlation between personal and stationary stations.