The more colours you use, the worse it gets. Printers have a number of methods at their disposal to deal with the VOC output of their plant, but their effectiveness in the broader environmental sense is questionable. The printing press can be cleaned afterward with a water-based cleaner. This is the most common conception of alternative inks. It's not true.
Soy inks are the same price as regular petrochemical inks.
Don't think for a second that we're disparaging the efforts of American soybean farmers whose organisation has, after all, seized the initiative and made a valuable and highly welcome product available on a global scale. But it's an illustration of the kind of dilemma that keeps frustrating any attempt to put a solid environmental platform together.