In the early 1970s, I was an editor at Rolling Stone magazine.
This was a time when bicycle riding had become quite popular for healthful exercize, so it was natural for me to invent something terrible that could be caused by bicycle riding.
I invented a mythical scientist at Johns Hopkins School of Medicine who found a problem with the high pressure tires commonly used on 10-speed "racing" bikes. He discovered that with each revolution of the tire, thousands of minute rubber particles were abraided by the road surface.
The rubber particles became airborne, and many were inhaled by the bike rider, particularly if he or she was riding bent over and face-down to minimize wind resistance and increase speed.
The scientist, whose phony name I've long forgotten, found that people who rode often developed lung cancer and black lung disease, like coal miners.