Abstract：
Ambient air ultrafine particles (UFP, particles with a diameter <100 nm) have gained significant attention in World Health Organization (WHO) air quality guidelines and European legislation. This review explores UFP concentrations and particle number size distributions (PNC-PNSD) in various transportation hotspots, including road traffic, airports, harbors, trains, and urban commuting modes (walking, cycling, bus, tram, and subway). The results highlight the lack of information on personal exposure at harbors and railway stations, inside airplanes and trains, and during various other commuting modes. The different lower particle size limits of the reviewed measurements complicate direct comparisons between them. Emphasizing the use of instruments with detection limits ≤10 nm, this review underscores the necessity of following standardized UFP measurement protocols. Road traffic sites are shown to exhibit the highest PNC within cities, with PNC and PNSD in commuting modes driven by the proximity to road traffic and weather conditions. In closed environments, such as cars, buses, and trams, increased external air infiltration for ventilation correlates with elevated PNC and a shift in PNSD toward smaller diameters. Airports exhibit particularly elevated PNCs near runways, raising potential concerns about occupational exposure. Recommendations from this study include maintaining a substantial distance between road traffic and other commuting modes, integrating air filtration into ventilation systems, implementing low-emission zones, and advocating for a general reduction in road traffic to minimize daily UFP exposure. Our findings provide important insights for policy assessments and underscore the need for additional research to address current knowledge gaps.
摘要：
环境空气超细颗粒(UFP，直径<100nm的颗粒）在世界卫生组织（WHO）空气质量指南和欧洲法规中获得了广泛关注。这篇综述探讨了不同运输热点地区的UFP浓度和颗粒数量分布（PNC-PNSD），包括道路交通，机场,港口,火车,和城市通勤模式(步行，骑自行车,公共汽车,电车,和地铁）。结果突出表明，缺乏有关港口和火车站个人接触的信息，在飞机和火车里，以及其他各种通勤模式。所审查的测量的不同的较低粒度限制使它们之间的直接比较复杂化。强调使用检测限≤10nm的仪器，这篇综述强调了遵循标准化UFP测量协议的必要性.道路交通站点显示出城市内最高的PNC，PNC和PNSD处于通勤模式，由接近道路交通和天气状况驱动。在封闭环境中,比如汽车,公共汽车,还有电车,通风的外部空气渗透增加与PNC升高和PNSD向较小直径的转变相关。机场在跑道附近表现出特别高的PNC，引发对职业暴露的潜在担忧。这项研究的建议包括在道路交通和其他通勤模式之间保持相当大的距离，将空气过滤集成到通风系统中，实施低排放区，并倡导普遍减少道路交通，以最大程度地减少UFP的日常暴露。我们的发现为政策评估提供了重要的见解，并强调需要进行更多的研究来解决当前的知识差距。
