Spagnolo Anna Maria, Ottria Gianluca, Perdelli Fernanda, Cristina Maria Luisa
Department of Health Sciences, University of Genoa, Italy Via Pastore, 1-16132 Genoa, Italy.
Int J Environ Res Public Health. 2015 Apr 13;12(4):4031-46. doi: 10.3390/ijerph120404031.
Exposure to the particulate matter produced in underground railway systems is arousing increasing scientific interest because of its health effects. The aim of our study was to evaluate the airborne concentrations of PM10 and three sub-fractions of PM2.5 in an underground railway system environment in proximity to platforms and in underground commercial areas within the system, and to compare these with the outdoor airborne concentrations. We also evaluated the metal components, the cytotoxic properties of the various fractions of particulate matter (PM) and their capacity to induce oxidative stress.
We collected the coarse fraction (5-10 µm) and the fine fractions (1-2.5 µm; 0.5-1 µm; 0.25-0.5 µm). Chemical characterisation was determined by means of spectrometry. Cytotoxicity and oxidative stress were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Reactive Oxygen Species (ROS) assessment.
The concentrations of both PM10 and PM2.5 proved to be similar at the three sampling sites. Iron and other transition metals displayed a greater concentration at the subway platform than at the other two sites. The 2.5-10 µm and 1-2.5 µm fractions of PM from all three sampling sites determined a greater increase in ROS; the intensity of oxidative stress progressively declined as particle diameter diminished. Moreover, ROS concentrations were correlated with the concentrations of some transition metals, namely Mn, Cr, Ti, Fe, Cu, Zn, Ni and Mo. All particulate matter fractions displayed lower or similar ROS values between platform level and the outdoor air.
The present study revealed that the underground railway environment at platform level, although containing higher concentrations of some particularly reactive metallic species, did not display higher cytotoxicity and oxidative stress levels than the outdoor air.
由于地铁系统产生的颗粒物对健康有影响，其暴露问题引起了越来越多的科学关注。我们研究的目的是评估地铁系统内靠近站台处和地下商业区环境中PM10以及PM2.5三个亚组分的空气浓度，并将其与室外空气浓度进行比较。我们还评估了金属成分、颗粒物（PM）各组分的细胞毒性特性及其诱导氧化应激的能力。
我们收集了粗颗粒组分（5 - 10微米）和细颗粒组分（1 - 2.5微米；0.5 - 1微米；0.25 - 0.5微米）。通过光谱法进行化学表征。通过3 -（4,5 - 二甲基噻唑 - 2 - 基）- 2,5 - 二苯基四氮唑溴盐（MTT）法和活性氧（ROS）评估来评价细胞毒性和氧化应激。
在三个采样点，PM10和PM2.5的浓度均相似。地铁站台处铁和其他过渡金属的浓度高于其他两个采样点。来自所有三个采样点的2.5 - 10微米和1 - 2.5微米的PM组分导致ROS的增加幅度更大；随着粒径减小，氧化应激强度逐渐降低。此外，ROS浓度与一些过渡金属的浓度相关，即锰、铬、钛、铁、铜、锌、镍和钼。站台层和室外空气中所有颗粒物组分的ROS值较低或相似。
本研究表明，站台层的地铁环境虽然含有较高浓度的一些特别具有反应性的金属物种，但与室外空气相比，并未表现出更高的细胞毒性和氧化应激水平。
