Fine Particulate Matter Emissions from Electric Vehicle Fast Charging Stations

The global shift to electric transportation necessitates expansion of Direct Current Fast Charging (DCFC) stations. However, the environmental and public health impacts of this expansion are not yet well understood. Here, we report that the power cabinet at DCFC stations emit fine particulate matter (PM _2.5 ), which are associated with increased morbidity through the life course and premature death. We collected 24-hr integrated filter samples from 50 DCFC stations across 47 cities in Los Angeles County, California, and found that daily PM _2.5 concentrations were between 7.3 to 39.0 µg m ^-3 , approximately twice the background levels. To understand the emission mechanism of these particles, we conducted extensive field measurements for real-time PM _2.5 mass concentration, particle size distribution, and other pollutants, as well as EV charging activities. We found that these particles are mainly in the sub-micrometer size range (0.5-1.0 µm) and are likely due to particle resuspension from the power cabinets. Currently, no emission standards exist for DCFC. Without regulation or interventions, these resuspended particles could expose nearby communities, EV users, and the workforce operating these facilities to high levels of PM _2.5 , potentially leading to widespread health consequences.