Diesel cars produced by manufacturers like Nissan, Hyundai, Citroen and Volvo have become embroiled in the emissions scandal, after they were found to emit higher levels of pollution in tests closer to real-life driving conditions than during EU emissions tests.
As reported by The Guardian, research from motoring association Adac claims that some diesel cars produced by these manufacturers emitted more than 10 times as much pollution as they did during EU emissions tests.
The higher emissions were revealed when the cars were put through the WLTC test, a different test to the EU standard NEDC test, and one that is designed to mimic ordinary driving more accurately.
According to Adac, the biggest disparity between test results was found in the Nissan X-Trail 1.6 cDi, which produced more than 14 times more harmful nitrogen oxide and nitrogen dioxide (NOx) in the WLTC test when compared to its EU test results.
Many other models, from companies like Jeep, Audi, Opel and Mercedes showed much higher emissions when tested by Adac.
The emissions scandal began when it was revealed that Volkswagen was using illegal software in their cars that could manipulate emissions and cheat US governmental tests.
The software could detect when the car was being tested and cause it to emit much lower NOx levels than it would usually emit during normal driving.
The CEO of Volkswagen, Martin Winterkorn, resigned after the scandal came to light, and the company is currently preparing a recall of an estimated 11 million vehicles that contain the illegal software - at a cost that it expected to reach £4.3 billion.
According to a Department for Environment and Rural Affairs document published this month, the limitations of the EU tests and Volkswagen's evasions of the law are listed as one reason for the high levels of NOx pollution across the UK.
Speaking to The Guardian, York University air pollution expert Professor Alistair Lewis said the costs of the scandals will be "thousands of deaths and billions of pounds, all passed on to the taxpayer."
Nitrogen dioxide is emitted by diesel cars and is proven to be harmful to humans. It can cause respiratory problems like shortness of breath and coughing, and can lead to inflammation of the lung's lining.
It has been estimated that Volkswagen's cheating resulted in an extra million tons of pollution being released into the atmosphere - more than the UK's total combined emissions from power stations, industry and agriculture.
