Integrated evaluation of VOCs pollution from a refuse transfer station: From source emissions to ambient exposure

Volatile organic compounds (VOCs) emitted from refuse transfer stations pose significant risks to air quality, the urban environment and human health. In this study, three field sampling campaigns were conducted across transfer station interiors, boundaries, roadsides, and residential areas to evaluate the impacts of VOC emissions. The highest total VOC concentrations were recorded inside the transfer station (1611-3822 μg/m³), with markedly elevated ozone formation potential (OFP), secondary organic aerosol formation potential (SOAFP), odor impact, and health risks compared to surrounding areas. Oxygenated VOCs (OVOCs) accounted for 58 % of total VOCs and were also the largest contributors to OFP (51.2 %) inside the station. In contrast, nitrogen compounds dominated VOC compositions at off-site locations (37-59 %) and contributed up to 55.9-79.4 % of the OFP at boundary and nearby ambient, likely due to traffic-related emissions. Aromatics, notably toluene and naphthalene, were the primary SOAFP contributors across all sites. In addition, the highest odor activity value (OAV = 1773) was observed inside the station, with isovaleraldehyde (20.8 %) and octanal (19.9 %) as dominant odorants. Health risk assessments indicated that both the station and its boundary areas exceeded tolerable thresholds, with naphthalene, 1,1,2-trichloroethane, and 1,2-dichloroethane as the key hazardous substances. Integrated assessment identified naphthalene, toluene, and isovaleraldehyde as multi-effect priority pollutants, underscoring the urgent need for targeted regulatory measures addressing emissions from refuse transfer stations.