Half-burned diesel particulate is absolutely cancerous, it can enter the bloodstream and cross the blood-brain barrier and they're generating clouds of it, probably thousands of times more than what a modern 18 wheeler puts out in half an hour of driving. And they're doing it to someone breathing hard.

If I sprayed some cancerous chemical in someone's face, I'd be arrested within the hour. I'd be on the regional news, even.

The double standards around motor vehicles never cease to amaze.