I was hoping to be able to use greenboard, because it's cheap and I like the finished look, plus I wouldn't have to worry about trimming the seams. As far as the corrosive gases, I use combustion blowers from hvac equipment. They can take the corrosive aspects, but the moisture kills them after about 5 years. Fortunately, I have an endless supply. The cool thing is that they're 230 volt, but when I run them at 120 volt, they run slow and quiet, and draw just enough to remove the "stinky", but not fast enough to be noisy or draw too much cold air into the loo in Wintertime.
As a side note....my cabin is on the grounds of an old dynamite factory. The ruins are evident everywhere,...on the flats, and even on the sides of the mountains. The area was chosen because the high humidity lessened the likelyhood of accidents. Looks like there were lots of small structures.
The last of the buildings were torn down in '57.
That aside, it's a picturesque area. You can drink from the streams worry free.
It's near Sinnemahoning, PA, off of Wykoff run rd.