Hi Digger,
Yes, I travelled by car 50 miles each way to work, for 5 years, 1980 to 1985.
So I was doing 100 miles every day for 5 years, just to work!!
Add to this all the social and holiday miles, and lived in my car.
I was diagnosed with PD just 6 years after leaving the 100 miles per day job. I then did 50 miles per day to work for 10 years,
I often thought about the fumes on the 100 miles per day job, and wondered what harm I was doing to myself. Now I know. This trip was mainly along a notoriously busy motorway,(interstate) road. There was a deep valley, known locally as "Death Valley," due to the fact that it was always shrouded in a dense fog of traffic fumes. All 6 lanes were affected, and there was an accident there daily as I went through it.

Ron