Field Demonstration of a Wearable Particulate Matter and Volatile Organic Compound Monitor
JESSICA TRYNER, Emilio Molina Rueda, Jane Andales, Casey Quinn, Christian L'Orange, Ellison Carter, John Volckens,
Colorado State University Abstract Number: 628
Working Group: Instrumentation and Methods
AbstractExposures to particulate matter (PM) and volatile organic compounds (VOCs) pose numerous health risks. These exposures vary in space and time both within and between microenvironments (occupational, residential, transit, etc.). The highest-fidelity estimate of personal risk is obtained by sampling air pollutants in a person’s breathing zone; however, data on personal PM and VOC exposures are limited—in part due to the cost and logistics of outfitting individuals with wearable sampling equipment. To improve the feasibility and scalability of personal PM and VOC exposure assessment, we developed a small (200 g), quiet (< 55 dB), wearable monitor that actively samples PM onto a filter and VOCs onto a thermal desorption tube. The monitor also includes a GPS and a suite of low-cost sensors to collect spatiotemporally-resolved data on environmental conditions (e.g., temperature and light) as well as PM and VOC levels. In a pilot study, we paired our new monitors with conventional personal sampling equipment to assess "at-work" and "away-from-work" exposures to PM
2.5 and VOCs for five employees at an agricultural research facility. Exposures varied among employees with different job tasks. Participants were exposed to one-week average PM
2.5 concentrations of up to 82 μg m
-3 at work. Time-resolved sensor data suggested that at-work exposures to PM
2.5 mass were dominated by windblown dust. Work shift-averaged personal exposures to BTEX (benzene, toluene, ethylbenzene, and xylenes) measured using the new monitors agreed with exposures measured using conventional personal sampling equipment (Spearman's correlation coefficient = 0.98; slope of line fit using Deming regression = 0.79). Time-resolved sensor data were used to identify specific at-work locations and activities associated with higher VOC exposures. Personal exposures to PM
2.5 and BTEX were typically lower when participants were away from work. These results illustrate the value of combining time-integrated pollutant samples with low-cost sensor data to gain knowledge on the timing and sources of personal exposures to air pollution.