A new study out in Nature Monday claims excess nitrogen oxide emissions from diesel vehicles were associated with approximately 38,000 premature deaths around the world in 2015.

• The worst cases: Most of the health impacts were in China, India, and the EU.
• The outlier: Heavy-duty vehicles were the dominant contributor to health impacts in all markets but the EU.

What to watch for: The study suggests if countries like Australia, Brazil, China and Mexico adopt the strictest current emissions standards, 104,000 premature deaths could be avoided in 2040.

The culprits in those estimates: One-third of emissions from heavy-duty diesel vehicles (buses and heavy-duty trucks) and over half of emissions from diesel cars exceed the certification limits for nitrogen oxide in 11 markets globally (Australia, Brazil, Canada, China, the EU, India, Japan, Mexico, Russia, South Korea, U.S.) that together make up about 80% of new diesel vehicle sales in the world.