Even the Newest 'Clean' Diesel Cars Release 'Toxic Smog,' Study Finds
A new analysis reveals that the latest models of diesel cars approved for sale since the 2015 Volkswagen "dieselgate" scandal are exceeding nitrogen oxides (NOx) limits set by the Europe Union.
For the study, the International Council on Clean Transportation (ICCT) used a "difficult-to-impossible to cheat" emissions test involving remote-sensing technology and statistical analysis to measure real-world exhaust emissions on more than 700,000 cars and 4,850 vehicle models across Europe.
The results were "a striking confirmation of [the] worst fears about diesel cars," said the U.S.-based ICCT, as quoted by the Financial Times.
According to their findings, all Euro 6 rated cars—the latest emissions standard for diesels—exceeded the Euro 6 diesel NOx emissions limits measured in real-world driving.
For Euro 6 cars in particular, the researchers also found:
- Four manufacturer groups had average emissions more than 12 times above the Euro 6 diesel type-approval limit, and the highest-emitting vehicle family has emissions 18 times the limit.
- All Euro 6 diesel models rated exceeded the Euro 6 diesel NOx emissions limits measured in real-world driving.
- The highest-emitting petrol Euro 6 vehicle family has approximately the same level of NOx emissions as the lowest-emitting diesel vehicle family.
The results were compiled in a new rating database called The Real Urban Emissions Initiative (TRUE). The study also found that all of the Euro 3, 4 and 5 diesels were in the red. Gasoline-fueled vehicles, in contrast, fared much better. Most Euro 3-5 petroleum vehicles had good or moderate ratings. And all Euro 6 petrol cars received a “good" or "moderate" rating.
NOx pollution, which is emitted by automobiles, trucks and various non-road vehicles, is harmful to human health and the environment. Emissions of NOx exhaust gases can be linked to 38,000 premature deaths worldwide, including 1,100 deaths in the U.S., according to University of Colorado Boulder researchers.
The EU has a baseline limit of 0.08mph of nitrogen oxides per kilometer. But as the Guardian noted, the TRUE analysis reveals that diesel models released in 2016 were still on average five times above that limit.
"We can really conclude that pretty much all Euro 6 diesels on the market are not clean," Peter Mock, managing director of the ICCT in Europe, told the Financial Times.
Greg Archer, of the campaign group Transport & Environment, which is part of the TRUE initiative, added to the Guardian: "The True rating exposes the legacy of dieselgate—tens of millions of dirty diesels that are still on the roads producing the toxic smog we daily breathe. It identifies the worst performing models and regulators must act to require carmakers to clean these up."
The European Automobile Manufacturers' Association, which represents 15 major Europe-based car, van, truck and bus makers, called the study "misleading."
They contend the study is based on remote sensing results collected between 2011 and 2017, and therefore do not evaluate the on-road performance of the latest diesel vehicles approved to the Euro 6 diesel standard since September 2017.
"The claims from the new 'TRUE' study are misleading for consumers," stated Erik Jonnaert, secretary general of the European Automobile Manufacturers' Association. "EU policy makers will be equally disappointed that there is no acknowledgement that the latest Euro 6 diesel cars complying with the new RDE legislation are very clean."