Ahhh, I love the smell of the darkroom in the morning or at night for that matter. However, I do know it is not an environmentally friendly hobby. Alas, I had to leave my beloved enlarger behind in the last move, so have not done any darkroom work for five years now. But, one of the things I tried to show my students, in the Chemistry of Photography class, was that there were a few environmentally friendly alternatives. One was to develop using fresh Mint leaves. The ones from the store do not work nearly as well as the leaves right out of the garden.
Chemical developer, Catechol, can irritate your skin, respiratory and digestive tracts and can be replaced with an alternative of mint leaves and Bicarbonate of Soda. I did not do any in-depth experiments with it and can only find one photo that I did develop with Mint leaves. It is very light.
The mint and bicarbonate developer must be used while it is still warm, or kept warm. You do need fresh from the garden mint leaves. You boil approximately one liter of water and add a large handful of fresh mint leaves. Add two rounded Tablespoons of Bicarbonate of soda to this and boil for approximately twenty minutes. Even though you must use it warm, I have read that it will keep up to 24 hours.
You still need to fix the print. I could never find an environmentally friendly alternative to fix.
Beside getting students to think about environmental alternatives, and this was about seven years ago, there was a certain satisfaction in the “Ehew” factor. For some reason, mint leaves floating in warm water seemed to gross them out. I never took the time to strain it.