Owing to the toxic and ubiquitous nature of vehicle derived particles, our early work at the University of Umea (see the photo) focused on controlled diesel exhaust exposure studies to understand the mechanisms through which diesel exhaust exacerbates respiratory disease, as identified in epidemiological research. To investigate effects on the airways, human volunteers (healthy and/or mild asthmatic) were exposed for one to two hours to whole diesel exhaust (particulates and the associated gas phase emissions) from an idling engine at concentrations ranging from environmentally relevant to those commonly experienced in busy diesel-dominated traffic environments.
By performing blood, bronchoalveloar lavage, and bronchial mucosal biopsy sampling after exposure, these studies have been instrumental in uncovering a systemic and pulmonary inflammatory response, attributed in part to the oxidative properties of exhaust PM (1‒7). |
Initial measures mainly focused on shutting down small industrial and domestic coal burning stoves and controlling dust from road and construction sites, as well as phasing out old vehicles that did not meet emission standards. During the Beijing Olympics in 2008 (12) and the Asia-Pacific Economic Cooperation meeting in Beijing in 2014, aggressive measures were taken to reduce the number of vehicles on the road by allowing cars to be used on only certain days of the week, determined by the last digit of the car license number. This measure resulted in substantial temporary reductions in congestion and pollution concentrations in Beijing and was considered so successful that it was made a routine rule immediately after the Olympics. Today, every car is allowed to drive four days per five weekdays. These efforts to control air pollution in Beijing have shown some success.
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