Study Shows Diesel Not Leading Particulate Matter Contributor
A new paper issued by the UNECE concluded that diesel road vehicles were the cause of only a small percentage of particulate matter versus other economic sectors.

A new paper issued by the United Nations Economic Commission for Europe (UNECE) concluded that diesel road vehicles were the cause of only a small percentage of particulate matter – PM 2.5 and PM10 - in Europe and the United States compared to economic sectors like the commercial, institutional, and household sectors.
“From the data and facts mentioned above, we conclude with a high degree of reliability that it is misleading to claim that people’s exposure to diesel engines of road motor vehicles is the cause of increased risk of lung cancer,” UNECO concluded in the new paper entitled “Diesel Engine Exhausts: Myths and Realities”.
Click here to read the entire UNECE paper.
“Eighty three percent of particulate matters emissions in European Union countries (EEA, 2012a) and 97 percent in the United States of America (EPA 2013) and Canada is generated by other economic sectors, mainly the commercial, institutional and household sector. Therefore, the claim that emissions from diesel engine exhausts from road transport are the main cause of lung cancer in humans needs to be seriously challenged. It does not mean however, that measures to improve the environmental performance of the transport sector can stop. On the contrary, they must continue and in an aggressively well targeted way,” the UNECE paper stated.
The new UNECE report has similar findings to a separate study published in the journal Nature Communications on May 13, 2014 entitled “Two-stroke scooters are a dominant source of air pollution in many cities”. This second report was supported by the Swiss Federal Office for the Environment (FOEN), the Federal Roads Office (FEDRO), the Swiss National Science Foundation, the EU commission, the UK Natural Environment Research Council (NERC), the French Environment and Energy Management Agency.
The study found that in many Asian and European communities: “Cars and trucks, particularly diesel vehicles, are thought to be the main vehicular pollution sources. This needs re-thinking, as we show that elevated particulate matter levels can be a consequence of ‘asymmetric pollution’ from two-stroke scooters, vehicles that constitute a small fraction of the fleet, but can dominate urban vehicular pollution through organic aerosol and aromatic emission factors up to thousands of times higher than from other vehicle classes.”
Click here to see a summary of the Nature Communications study.
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