Delville Laurence, Léon Jean-François, Macouin Mélina, Tastevin Yann-Philippe, Demory François, Proietti Arnaud, da Silva Chibane Pedro Henrique, Dias Alves Maria, Gueye Mayoro, Laffont Laure, Gardrat Eric, Rousse Sonia, Drigo Loic, Ustra Andréa Teixeira
Laboratoire d'Aérologie, Université de Toulouse, CNRS, IRD, UPS, Toulouse, France.
Géosciences Environnement Toulouse, Université de Toulouse, CNES, CNRS, IRD, UPS, Toulouse, France.
Environ Sci Pollut Res Int. 2025 Jan;32(2):677-692. doi: 10.1007/s11356-024-35729-x. Epub 2024 Dec 19.
Road traffic is one of the main sources of particulate matter in the urban environment, emitting particulate organic and elemental carbon compounds and metal-rich particles through combustion and brakes and tires wear. In Western Africa, the carbon and metal composition of airborne particles is also influenced by additional sources linked to biomass combustion and recent industrialization. Here, we investigated the impact of combustion-related and non-combustion-related emissions on the distribution of carbonaceous fractions and iron-rich particles in two urban environments in France and Senegal. The supermicron fraction ( µm) showed a significantly higher isothermal remanent magnetization (SIRM) than finer fractions, accounting for 79% in France and 81% in Senegal of the total SIRM. In the submicron fraction ( µm), we noted significantly higher concentrations of total carbon (TC) and elemental carbon (EC) than for other fractions, both accounting for 71% in France and 68% and 75% in Senegal of the total and elemental particulate carbon concentration, respectively. Electron microscope observations revealed the presence of iron-rich particles for µm, however, associated with a weak SIRM. Such iron particles may be produced by combustion or abrasion while we suspect that emissions by the abrasion process produce larger particles.
道路交通是城市环境中颗粒物的主要来源之一，通过燃烧以及刹车和轮胎磨损排放颗粒有机化合物、元素碳化合物和富含金属的颗粒。在西非，空气中颗粒物的碳和金属成分还受到与生物质燃烧和近期工业化相关的其他来源的影响。在此，我们研究了与燃烧相关和与非燃烧相关的排放对法国和塞内加尔两个城市环境中碳质组分和富铁颗粒分布的影响。超微米级组分（ µm）的等温剩磁（SIRM）明显高于较细的组分，在法国占总SIRM的79%，在塞内加尔占81%。在亚微米级组分（ µm）中，我们注意到总碳（TC）和元素碳（EC）的浓度明显高于其他组分，在法国分别占总颗粒碳浓度和元素颗粒碳浓度的71%，在塞内加尔分别占68%和75%。电子显微镜观察发现存在 µm的富铁颗粒，然而，其SIRM较弱。这种铁颗粒可能是由燃烧或磨损产生的，而我们怀疑磨损过程产生的排放会产生更大的颗粒。
