Crowdsourced, Community-Engaged Volatile Organic Compound Monitoring and Source Apportionment near the Bristol...

Municipal solid waste landfills can emit complex mixtures of volatile organic compounds (VOCs), but community exposures are difficult to characterize because concentrations vary across space and time and may be influenced by episodic odor events, meteorology, and nonlandfill sources. Community-engaged research approaches can help address these challenges while incorporating residents' local knowledge and concerns into monitoring study design. We conducted a community-engaged citizen-science study using a modified Ultrasonic Personal Air Sampler operated in accordance with U.S. EPA Method TO-17 to assess outdoor VOCs near the Bristol Virginia Solid Waste landfill. Concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX) remained below U.S. EPA Reference Concentrations during sampling, but were significantly higher on "Stinky" nights, suggesting elevated levels of selected VOCs during odor-relevant periods. However, measured VOCs did not fully explain odor perception, likely because odor-active sulfur-containing compounds were not captured and odor events were spatially and temporally variable. Source apportionment indicated that, in addition to landfill-related emissions, traffic-related sources contributed substantially to outdoor BTEX. Estimated noncarcinogenic and carcinogenic risks were within levels of low health concern. These results demonstrate the feasibility of conducting more scalable, cost-effective near-reference monitoring through a community-engaged framework enabled by innovative sampling technology.