p-Aminophenol is far more widely used in hair dyes and in far larger quantities than the volumes of Rodinal used.

The actual amount of p-Aminophenol, sulphite and hydroxide used per film is likely to be far less polluting than most more concentrated developers (at working strength), somewhere I have the Toxicology figures for Colour processing because I had to deal with the regulatory authorities, in the UK there it is the water boards, because they have to treat the water and make it fit for human consumption.

In an average household there are far worse pollutants disposed of in a normal week.

Even a developer like Xtol used 1+1 is far worse than dilute Rodinal, so coming up with something more environmentally friendly is going to be difficult.

Ian