Rather than being an individual launch, I'm wondering if the exhaust from transfers (from LEO to other orbits) leave gases in their own orbit, and if a particular transfer is happening a lot, the gasses would accumulate in their own distinct orbit.

Context: I worked on a satellite that observed interesting phenomenon that appeared in low-visible-light around the Earth, and one of the things we picked up as noise was the gas from a spy satellite doing a transfer near the Earth-Sun line of sight.