Category Archives: NOx

The Internal Combustion Engine Is Bad For Your Health — What Should We Do About It?

I’ve written a lot about how the developing science around particulate exposure supports making the PM2.5 NAAQS more stringent.  So it won’t come as a surprise that a new study published in the Proceedings of the National Academy of Sciences indicates that the benefits of on-road emissions reductions from 2008 to 2017 could be measured in the hundreds of billions of dollars and almost 10,000 fewer deaths. … More

EPA Will Reconsider the Ozone NAAQS — What Is An Adequate Margin of Safety, Anyway?

On Friday, EPA announced that it was reconsidering its 2020 decision to leave the National Ambient Air Quality Standards for ozone unchanged.  The reconsideration will be based on the existing record.  The notice does not identify any specific perceived flaws in the 2020 decision.  However, EPA stated that it:

will reconsider the decision to retain the ozone NAAQS in a manner that adheres to rigorous standards of scientific integrity.… More