Source apportionment of magnetite particles in roadside airborne particulate matter
| Autor: | Tomasz Gonet, Barbara A. Maher, Jana Kukutschová |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Environmental Engineering
010504 meteorology & atmospheric sciences Potential risk Air pollution 010501 environmental sciences Particulates medicine.disease_cause complex mixtures 01 natural sciences Pollution chemistry.chemical_compound chemistry Urban background Environmental chemistry Magnetic components medicine Environmental Chemistry Environmental science Vulnerable population human activities Waste Management and Disposal 0105 earth and related environmental sciences Vehicle brake Magnetite |
| Zdroj: | The Science of the total environment. 752 |
| ISSN: | 1879-1026 |
| Popis: | Exposure to airborne particulate matter (PM) is associated with pulmonary, cardiovascular and neurological problems. Magnetite, a mixed Fe2+/Fe3+ oxide, is ubiquitous and abundant in PM in urban environments, and might play a specific role in both neurodegeneration and cardiovascular disease. We collected samples of vehicle exhaust emissions, and of heavily-trafficked roadside and urban background dusts from Lancaster and Birmingham, U.K. Then, we measured their saturation magnetic remanence and used magnetic component analysis to separate the magnetite signal from other contributing magnetic components. Lastly, we estimated the contributions made by specific traffic-related sources of magnetite to the total airborne magnetite in the roadside environment. The concentration of magnetite in exhaust emissions is much lower (3–14 x lower) than that in heavily- trafficked roadside PM. The magnetite concentration in petrol-engine exhaust emissions is between ~0.06 and 0.12 wt%; in diesel-engine exhaust emissions ~0.08–0.18 wt%; in background dust ~0.05–0.20 wt% and in roadside dust ~0.18–0.95 wt%. Here, we show that vehicle brake wear is responsible for between ~68 and 85% of the total airborne magnetite at the two U.K. roadside sites. In comparison, diesel-engine exhaust emissions account for ~7% - 12%, petrol-engine exhaust emissions for ~2% - 4%, and background dust for 6% - 10%. Thus, vehicle brake wear is by far the most dominant source of airborne magnetite in the roadside environment at the two sites examined. Given the potential risk posed, post-inhalation, by ultrafine magnetite and co-associated transition metal-rich particles to human cardiovascular and neurological health, the high magnetite content of vehicle brake wear might need to be reduced in order to mitigate such risk, especially for vulnerable population groups. © 2020 Elsevier B.V. |
| Databáze: | OpenAIRE |
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