National-scale investigation of EV charging stations in China reveals emerging microbial contaminant sources

Abstract

As the adoption of electric vehicles (EVs) proliferates, EV charging stations, pivotal to transportation infrastructure, may become potential hubs for microbial contamination, posing public health risks. Here, we investigated the distribution patterns and underlying drivers of microbial contaminants on charging station surfaces across 63 service areas within the Chinese highway network. The results demonstrate the widespread distribution of human pathogenic bacteria (HPBs, 100%), human pathogenic fungi (HPFs, 49.21%), antibiotic resistance genes (ARGs, 100%), and virulence factor genes (VFGs, 100%) on charging station surfaces, with hierarchical partitioning analysis revealing that a multifaceted interplay of factors drives their distribution. The primary determinants, particularly road network density and service area size, influence the spatial pattern of ARGs and VFGs. Biotic factors significantly regulate the distribution of HPBs, whereas climatic factors emerge as the principal driver of shifts in human pathogenic fungal communities. Moreover, we assessed the potential risks associated with the detected ARGs, identifying 45 ARGs in high-risk categories Q1 and Q2 with a high prevalence (93.33%) and a pronounced abundance, particularly in southern coastal regions. These discoveries deepen our comprehension of microbial community distributions and potential assemblages on charging stations, thereby providing a robust scientific foundation for anticipatory assessments of their impacts on human health within highway systems. However, to fully understand the implications of these findings for public health, further studies should include microbial viability testing and longitudinal exposure assessments to evaluate actual infectivity and transmission potential.