title: Concentrations, properties, and health risk of PM2.5in the Tianjin City subway system.
abstract: A campaign was conducted to assess and compare the personal exposure in L3 of Tianjin subway, focusing on PM2.5levels, chemical compositions, morphology analysis, as well as the health risk of heavy metal in PM2.5. The results indicated that the average concentration of the PM2.5was 151.43 μg/m3inside the train of the subway during rush hours. PM2.5concentrations inside car under the ground are higher than those on the ground, and PM2.5concentrations on the platform are higher than those inside car. Regarding metal concentrations, the highest element in PM2.5samples was Fe; the level of which is 17.55 μg/m3. OC is a major component of PM2.5in Tianjin subway. Secondary organic carbon is the formation of gaseous organic pollutants in subway. SEM-EDX and TEM-EDX exhibit the presence of individual particle with a large metal content in the subway samples. For small Fe metal particles, iron oxide can be formed easily. With regard to their sources, Fe-containing particles are generated mainly from mechanical wear and friction processes at the rail-wheel-brake interfaces. The non-carcinogenic risk to metals Cr, Ni, Cu, Zn and Pb, and carcinogenic hazard of Cr and Ni were all below the acceptable level in L3 of Tianjin subway.
authors: College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China. wbqchina@hotmail.com.
authors: Bao-Qing
authors: BQ
authors: Wang
authors: College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors: Jian-Feng
authors: JF
authors: Liu
authors: College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors: Zi-Hui
authors: ZH
authors: Ren
authors: College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors: Rong-Hui
authors: RH
authors: Chen
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000633:toxicity; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D005290:Ferric Compounds / Q000032:analysis / Q000633:toxicity; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity; D052638:Particulate Matter / Q000032:analysis* / Q000633:toxicity; D011890:Railroads
chemical_list: D000393:Air Pollutants; D005290:Ferric Compounds; D019216:Metals, Heavy; D052638:Particulate Matter; C000499:ferric oxide
keywords: Elemental metals; Health risk; Iron; PM2.5; Subway