Daniel and Pete both put their fingers on the wounds, and Nigel found the keyword: the big picture. In fact, none of us is able to see this big picture. If the manufacturers had their way, we wouldn't even know that darkroom chemistry (or computer manufacture, for that matter) are bad for the environment. Both technologies are bad for the environment, the wet way because of the hazardous chemicals it uses, which are not collected for recycling, and the digital way because a lot of chemicals and energy are used to produce the hardware. Later, in use, the energy consumption is the main issue.(posted 8502 days ago)As a rule, it is easier to keep the recycling chain unbroken when as many of the environmentally harmful processes as possible are centralised, i.e. at the plant of a manufacturer. This is in favour of computers. It is possible to keep most of the hazardous stuff in the plant for recycling. On the other hand, centralised production requires additional energy to transport the goods to the consumer. Whether more energy is consumed by shipping computers around the world or by shipping photo chemistry, is a question which probably no one can answer because it strongly depends on the life cycles of the computer hardware in question.
When going the wet way, you may look for less toxic chemistry. XTOL is probably a good choice in this respect as it contains much less of the conventional, mostly highly toxic agents. For prints, Agfa's Neutol Plus (Vitamin-C-based like XTOL) is similar. You should also make sure you don't dump hazardous stuff down the drain just because it's so convenient to believe it's biodegradable. It is not too difficult to collect the material to bring it to a collection point for incineration at a specialised plant, if such an infrastructure exists.
Regards, Thomas Wollstein