Surprisingly, there is little public awareness of the issue of particulate matter exposure in urban centers. All the more so as the pathogenicity and epidemiological relevance are backed by robust scientific evidence (1). Similarly, the medical community seems to be lacking the necessary determination and consistency to do what clearly needs to be done. Here, similarities with the hesitant acceptance of the risks of smoking in the 1950s spring to mind.
Given the risks associated with traffic-related particulate matter emissions, some thoughts on automotive engineering and emission standards from a “medical” perspective seems to be worthwhile.
It is a paradox: Vehicles with up-to-date gasoline direct-injection engines emit more particulate matter than older gasoline-powered vehicles with controlled catalytic converters (2). The transitional provisions to the Euro 6 emission standard allow this to happen until 2017, as the proper number of emitted particles is not effectively limited.
This is a tragic development: Efforts to achieve emission goals are thwarted by higher powered engines, increasing numbers of SUVs on the road and dubious consumption measurement practices, while much-trumpeted alternative electrical or gas-powered vehicles struggle to gain any relevant market share and particulate matter emissions from the popular gasoline direct-injection engines continue to increase. As the reduction of particulate matter emissions is easily achieved with filters (3), automotive manufacturers are not made aware of their responsibilities to the extent necessary.
Presently, the limit values for particle pollution are only exceeded at urban monitoring sites, for example in Berlin and Stuttgart. Recently, however, the limit value for smallest-size particles (PM 2.5) has been lowered by the US Environmental Protection Agency to about half of the European limit value. Based on the available evidence, this step should be considered imperative here in Europe as well. The relationship between particulate matter exposure and preventable disease should prompt the medical community to play a more active role when it comes to setting and enforcing limit values—and also to critically reflect on one’s own choice of a vehicle.
Dr. med. Ramin Tavakolian
Conflict of interest statement
The author declares that no conflict of interest exists.
|1.||Lepeule J, Laden F, Dockery D, Schwartz J: Chronic exposure to fine particles and mortality: an extended follow-up of the Harvard Six Cities, study from 1974 to 2009. Environ Health Perspect 2012; 120: 965–70 MEDLINE|
|2.||Koehler F: Testing of particulate emissions from positive ignition vehicles with direct fuel injection system. Technical Report 2013; www.transportenvironment.org/sites/te/files/publications/TUV-Techni cal_report.pdf|
|3.||Mamakos A: Report by the Joint Research Centre of the European Commission: Feasibility of introducing particulate filters on gasoline direct injection vehicles—A cost benefit analysis 2011, JRC68675.|
|4.||Hoffmann B, Weinmayr G, Hennig F, et al.: Air quality, stroke and coronary events—results of the Heinz Nixdorf Recall Study from the Ruhr region. Dtsch Arztebl Int 2015; 112: 195–201.|