Guinea pigs

Did German carmakers really test emissions on humans?

Kicking up quite a stink. Source: DPA

While VW, Daimler and BMW spent most of the week falling over themselves to condemn their exhaust emission tests on monkeys, they must also have been breathing a sigh of relief.

A couple of days after the news broke of the monkey experiments in the US, a report in the Stuttgarter Zeitung, a regional newspaper in southern Germany, accused the big three carmakers of also conducting emissions tests on humans. The potential for outcry was far larger, yet the news seemed to raise few heckles, especially in Germany.

So did VW, Daimler and BMW really take a step beyond animal testing and expose human guinea pigs to toxic exhaust gases in the name of research? It depends who you ask.

First, the facts. In 2007 the trio, along with car-parts supplier Bosch, set up a research-based lobby group called the European Research Group on Environment and Health in the Transport, known by its German acronym EUGT. It was tasked with using science to demonstrate that diesel fumes were not a significant risk to human health. Bosch left the group in 2013.

At least 38,000 people die early each year because of the failure of diesel vehicles to meet official nitrogen oxide emissions limits.

The group funded many studies, including the monkey emissions tests in May 2014. But because of an obvious bias, the lobby group’s work was largely discredited and, as a result, it was wound up last year.

But before this, in 2013, the EUGT jointly funded an “inhalation study with nitrogen dioxide in healthy people.” Nitrogen dioxide (NO2) is one of the key toxins in diesel exhaust and a common pollutant. It is one of the nitrogen oxides, or gases, VW sought to artificially reduce with its emissions rigging software.

The tests into workplace pollution were carried out on 25 volunteers at Aachen University Hospital by Thomas Kraus, a professor of occupational and environmental medicine. He exposed the group for three hours in a 40 sq m (430 sq ft) room to different levels of NO2, from the natural background amount to three times the average workplace level, which is far above World Health Organization recommended limits. The volunteers were first asked to ride exercise bikes and then sit at a table. No other toxins or exhaust gases were involved, and the experiment was signed off by the ethics committee of the faculty. It classified the experiment as “justifiable” because of the short exposure to NO2.

The results, published in 2016, provided good news for the carmakers. They showed “no reactions to the inhaled NO2,” not even any inflammation in the airways. But Prof. Kraus noted that the results were not transferable to the general population as, for example, the volunteers were all non-smokers and none had asthma, plus the toxin was used in isolation. This meant the test could not be used to draw conclusions on the overall effect of air pollution on human health. However, Prof. Kraus feared they could be “instrumentalized,” although he did not say by whom. He added that the EUGT had not “impinged” on the research.

In a press conference on Friday, Prof. Kraus went further, saying he had been “abused” by the car industry. His team had believed the EUGT was a reputable organization and they had been unaware of the source of its funding, he added.

Daimler declared itself appalled by the experiments: “We are shocked by the extent of the studies and their implementation… and condemn the trials in the strongest terms.” The company said it had no influence on the experimental structure and had “launched a comprehensive investigation into how it could come about.”

But the effect of nitrogen oxides on human health is not in doubt. A study published last year in the leading journal Nature found that at least 38,000 people die early each year because of the failure of diesel vehicles to meet official nitrogen oxide emissions limits. Most deaths are from heart and lung disease and strokes.

And this week, Sir David King, Britain’s chief scientific officer between 2000 and 2007, said that German carmakers “have blood on their hands” for rigging experiments that convinced him to advise the then-government to favor diesel cars. “The number of early fatalities in Britain is really very, very large due to nitrogen oxide air, with governments across Europe encouraging diesel on the basis that the catalyst traps worked,” he told The Daily Telegraph.

But it seems that Daimler and VW want to pass the buck. Daimler said that “all the research carried out by the EUGT was accompanied and examined by a research advisory board made up of scientists from well-known universities and research institutes,” while VW said in its own statement that “the scientific methods used by EUGT were wrong.” It seems the professors are to blame, not the industry.


David Reay is an editor at Handelsblatt Global. To contact the author:

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