School of Architecture and Urban Planning, Shenzhen University, 3688 Nanhai Avenue, Shenzhen 518060, China.
Int J Environ Res Public Health. 2022 May 10;19(10):5830. doi: 10.3390/ijerph19105830.
Exposure to inhalable particulate matter pollution is a hazard to human health. Many studies have examined the in-transit particulate matter pollution across multiple travel modes. However, limited information is available on the comparison of in-transit exposure among cities that experience different climates and weather patterns. This study aimed to examine the variations in in-cabin particle concentrations during taxi, bus, and metro commutes among four megacities located in the inland and coastal areas of China. To this end, we employed a portable monitoring approach to measure in-transit particle concentrations and the corresponding transit conditions using spatiotemporal information. The results highlighted significant differences in in-cabin particle concentrations among the four cities, indicating that PM concentrations varied in an ascending order of, and the ratios of different-sized particle concentrations varied in a descending order of CS, SZ, GZ, and WH. Variations in in-cabin particle concentrations during bus and metro transits between cities were mainly positively associated with urban background particle concentrations. Unlike those in bus and metro transit, in-cabin PM concentrations in taxi transit were negatively associated with urban precipitation and wind speed. The variations in particle concentrations during the trip were significantly associated with passenger density, posture, the in-cabin location of investigators, and window condition, some of which showed interactive effects. Our findings suggest that improving the urban background environment is essential for reducing particulate pollution in public transport microenvironments. Moreover, optimizing the scheduling of buses and the distribution of bus stops might contribute to mitigating the in-cabin exposure levels in transit. With reference to our methods and insights, policymakers and other researchers may further explore in-transit exposure to particle pollution in different cities.
可吸入颗粒物污染对人体健康构成危害。许多研究已经考察了多种交通方式下的运输过程中颗粒物污染。然而，关于经历不同气候和天气模式的城市之间运输过程中暴露差异的信息有限。本研究旨在考察中国内陆和沿海四个特大城市出租车、公共汽车和地铁通勤过程中车内颗粒物浓度的变化。为此，我们采用便携式监测方法，使用时空信息来测量运输过程中的颗粒物浓度和相应的运输条件。结果突出了四个城市之间车内颗粒物浓度的显著差异，表明 PM 浓度按 CS、SZ、GZ 和 WH 的顺序递增，不同粒径颗粒物浓度的比例按降序排列。城市间公共汽车和地铁运输过程中车内颗粒物浓度的变化主要与城市背景颗粒物浓度呈正相关。与公共汽车和地铁运输不同，出租车运输过程中车内 PM 浓度与城市降水和风速呈负相关。行程中颗粒物浓度的变化与乘客密度、姿势、调查人员在车内的位置和车窗状况显著相关，其中一些因素表现出交互作用。我们的研究结果表明，改善城市背景环境对于减少公共交通微环境中的颗粒物污染至关重要。此外，优化公共汽车的调度和公共汽车站的分布可能有助于降低运输过程中的车内暴露水平。参考我们的方法和见解，政策制定者和其他研究人员可以进一步探索不同城市运输过程中颗粒物污染的暴露情况。
