Composting

good question, I'd like to know the answer too

 

Shiney - Welcome to the Forum. I am not totally sure of the answer as it is a complicated subject.

I believe that black print, especially cheap print such as newspapers is essentially soot (ie carbon) and harmless. It is combined with solvents, but these are also organic and essentially harmless.

Coloured print is the problem. There is a move to base colour on organic compounds (ie harmless), but traditionally the best and brightest colours come from salts of heavy metals, such as Cadmium, Chromium etc. Most of these are poisonous and should not be composted.

My gut feeling is that newspapers can be composted quite happily, even when they contain small amounts of colour (on cost grounds they are unlikely to contain much if any heavy metals). But I would not compost the glossiest, brightest coloured junk mail or magazines.

Try this site:- http://pubs.acs.org/cen/whatstuff/stuff/7646scit2.html