I believe so. See the hygroscopicity chart I posted earlier. In 50% relative humidity the equilibrium weight gain is 20%. A liter of dry TEA weighs 1126 grams. In equilibrium with 50% humid air it will weigh 225 grams more. I don't really know how much water it takes to allow developers dissolved in TEA to become active. I once placed a piece of film in a saucer of PC-TEA in light and saw no response over some period of time, but do not remember how long. It was reported in my original article in Photo Techniques. You can do the same sort of experiment with HC-110 concentrate with the same results. But add a bit of water and see what happens.
Originally Posted by Olli J