“Breathing NOX is like taking Viagra or nitroglycerin or niacin. It won’t hurt you.”
1. Learn what NOX stands for.
2. Look up NO2 toxicity.
Breathing NOX happens every day at dentists offices. It is also known as laughing gas. It is also used widely in drag racing to boost engine performance.
The toxicity you mention is only in extremely large concentrations. Exposure to anything in extremely high levels is not good, naturally.
The problem with the EPA is that is another one they have claimed is a greenhouse gas. The term greenhouse gas is an instant BS warning flag for me.
Still, emission occurred out in the middle of nowhere, where they would be quickly diluted and ultimately broken down.