Was it all marketing hype? If the USA and EU’s standards are so strict, where do other countries stand?
Diesel cars, trucks, and other vehicles in more than 10 countries around the world produce 50 percent more nitrogen oxide emissions than lab tests show, according to a new study. The extra pollution is thought to have contributed to about 38,000 premature deaths in 2015 globally.
In the study, published today in Nature (http://nature.com/articles/doi:10.1038/nature22086), researchers compared emissions from diesel tailpipes on the road with the results of lab tests for nitrogen oxides (NOx). A report in January (https://www.theverge.com/2017/1/6/14188676/diesel-cars-toxic-emissions-nitrogen-oxides-trucks-buses-europe) found that modern diesel cars in Europe produce more toxic emissions than trucks and buses, because cars have less strict regulations, and even if they meet lab tests, they emit more NOx when driven on actual roads.
See https://www.theverge.com/2017/5/15/15642456/diesel-vehicles-nitrogen-oxide-pollution-premature-deaths 
Diesel engines pollute much more than we thought — and that’s bad for our health
Diesel cars, trucks, and other vehicles in more than 10 countries around the world produce 50 percent more nitrogen oxide emissions than lab tests show, according to a new study. The extra…