In Europe, especially in Italy, Germany and France, diesel vehicles make up a huge proportion of the number of cars on the road. There's around 100 million of them zooming around the continent, almost twice as many as in the rest of the world combined. But more diesel vehicles means far more Nitrogen Oxides are released into the local atmosphere, with real-world consequences.

Of course, the issue here is that diesel cars have proliferated, in part, because they have been found to pass emissions tests. Tests which, thanks to Dieselgate, we now know were passed because the engines were tweaked to mask their true pollution levels from regulators.

The group is made up of researchers from Norway's Meteorological Institute, Austria's IIASA and the Department of Space, Earth and Environment at Chalmers University, Sweden. They report that around 425,000 deaths can be traced back to levels of air pollution across Europe more generally. Of that figure, around 10,000 can be attributed to Nitrogen Oxide levels produced by diesel vehicles.

The idea is that, if diesel vehicles hadn't cheated their tests, it's likely that many of them wouldn't have been made available for sale. Instead, petrol cars may have been sold in their place, with a consequential reduction in NOx emissions -- although still a toll to the wider environment. The IIASA's Jens Borken-Kleefeld believes that if petrol cars replaced the diesel vehicles, the deaths of up to 7,500 people could have been avoided.

This is an emotive subject and one that doesn't deserve to be sensationalized, and other studies have come to similar conclusions. But it's worth realizing that emissions cheating wasn't simply a clever way to escape some burdensome red tape. Lives have been lost in the service of a quick fix by several large automotive manufacturers.

Update: This post has been updated to clarify the researchers' findings that higher than normal emission levels due to Dieselgate are to blame up to 5,000 premature deaths, not 7,500. That's the number of preventable deaths if diesel vehicles had the same emissions levels as gas-powered cars.