I suspect the constant ringing in my ear is due to poppers

Seems to worsen after use. Have you heard any others reporting this issue?

The correct term for this ringing sound you hear is tinnitus.

And you are totally right : poppers do indeed increase tinnitus, as all other nitrates do (angina medication, toothpastes for sensitive teeth, skin exfoliators).

As fate loves irony, many popper users are also smokers. Nicotine also increases tinnitus greatly.

Of course, there are many other causes for tinnitus (Aspirin overuse, anemia, for instance) and tinnitus also seems to have genetic bases.
This being said, each possible causes will increase your tinnitus, so if you have a family background of tinnitus, smoke, brush you teeth with Sensodyne, and use poppers, each of these will independently increase the intensity of your tinnitus. Obviously you can’t do much for your genes, but you can control the other factors…