When it comes to environmental friendliness, you always have to weigh things up. In principle, you’re asking the right questions.
First of all: XT-3 still contains a classic developing agent; it doesn’t develop using ascorbic acid alone, but it is the best formula for a commercial developer, offering very good performance with the lowest possible environmental impact. We could, for example, also bring out a developer that contains absolutely no substances that are in any way toxic and which you could drink (if further diluted or neutralised to adjust the pH) – if you really wanted to – but this developer would not keep well and would only achieve half the ISO sensitivity. That’s why the project is still on the back burner. A comparison between HC-110 and XT-3 is also interesting. ADOX HC-110 ‘Original Syrup’ keeps almost indefinitely, even once opened. Anyone who engages in sporadic film development and develops very few films would (have to) constantly dispose of developer that has gone off when using XT-3. I can’t calculate this precisely right now, but of course, at some point, this would have a greater environmental impact (however you define that: resource consumption, biodegradability, etc.). So a highly concentrated, long-lasting developer can actually be the most environmentally friendly choice for some people, even though another developer contains fewer pollutants. Although RODINAL carries all sorts of warnings, when highly diluted it is, in principle, completely harmless and shouldn’t even need to be classified as a pollutant. It’s also more environmentally friendly to simply tip it away than to carry all the water off for disposal, but here, unfortunately, the law is caught in a vicious circle due to a lack of willingness to differentiate. RODINAL contains only paracetamol as its developing agent, along with some potassium hydroxide and a few salts. As a concentrate, it naturally carries every hazardous substance symbol, but not the 1+25 or 1+50 labels. So you can’t always rely on the warning labels. The issue is complex and begins with the question: which environmental aspect is the most important?
