In the 1990s, carmakers used their political clout to persuade European leaders that diesel helped fight climate change because it burns more efficiently than gasoline. As a result, almost all European countries now tax diesel at a lower rate than gasoline, making it cheaper at the pump. The carmakers maintained that modern technology had solved diesel’s big downside: emissions of nitrogen oxides and fine soot particles that can contribute to asthma, heart attacks and cancer. David King, a former chief scientific adviser to the British government, recalled being taken to a lab in the early 2000s where 10 diesel vehicles were running on rollers. The air was so clean that Mr. King, an asthmatic, could breathe freely. What Mr. King did not know is that most European automakers had built their diesel cars to pass laboratory emissions tests and no more. On the road, according to recent studies by the governments of Britain, France and Germany, diesel cars by almost all European manufacturers spewed toxic gases in quantities far above those allowed by law. “We were all misled by the car manufacturers,” Mr. King said in an interview. The toll on public health has become impossible to ignore. In 2012, 72,000 people in Europe died prematurely because of nitrogen dioxide pollution, which comes primarily from diesel vehicles, according to a report released last year by a committee of the European Parliament. Research sponsored by industry “all has the same fundamental aim,” said Joachim Heinrich, an environmental health expert at the University of Munich who has spent his career studying the effects of air pollution, “namely to weaken or discredit regulation — to say ‘the evidence is not that clear,’ ‘we shouldn’t take it so seriously,’ ‘we need to think more about it.’”
German auto ##maker Volkswagen manipulated emissions in a 2014 study it conducted to prove new diesel vehicles were “ cleaner ” than older models , according to a lawsuit filed against the manufacturer . The company commissioned a study involving 10 monkeys to be exposed to fumes from a modern diesel vehicle . It is reported VW provided scientists conducting the study with a modified diesel model different to cars sold to the general public . VW has already paid $ 500 in fines having admitted to tampering with emissions standards for its vehicles .