While researching in the Library’s periodicals yesterday, I read an article in Heirloom Gardener about getting tomatoes to ripen earlier. One of the steps was to put down a thick layer of newspapers, which would decompose and later be turned in to the soil. I am concerned about this being organic. However, the Internet sites I found were divided depending on the type of ink used. They made no mention of bleach or other chemicals used in production of the paper, but I wonder about that too. Finally, not many seemed very up to date.
Can you find better information?
There is a question like yours answered by George Weigel in PennLive.com, in which he suggests that it is probably relatively safe, given that many newspapers are now printed using soy-based inks. Here is an excerpt:
“That doesn’t mean there still aren’t people recommending against newsprint for various reasons (i.e. ‘What about the waxes, pigments and other additives that might be in soy ink?’ ‘Aren’t a majority of soybeans genetically modified, so doesn’t that taint soy ink as a natural product?’ And ‘How do we know for sure that someone didn’t slip something toxic into a batch of ink or that the newspaper temporarily switched to questionable ink because it found a bargain somewhere?’)
“I guess you could argue that newsprint ink might not be ‘safe’ for those kinds of reasons, but then you could argue that just about anything in gardening poses a threat (what’s in the water you’re using, your fertilizer, fungicide-treated seeds, genetically modified corn varieties, pathogens in the compost, even the air you’re breathing while putting down your newspaper mulch).”
Like you, I’ve wondered about newspapers as mulch, or as a shredded addition to the worm bin, too. One could not say that the papers and their inks are “organic,” but most sources (like the one above) seem to say that the amount of toxicity that might still be present is small compared to other sources of toxins in our environment.
As far as use of newspaper in organic gardens, the Organic Materials Review Institute (which lists what is and is not allowed in certified-organic growing) covers this:
Newspaper is “allowed with restrictions” when used for pest, weed, or disease control, and is classified as a synthetic (not organic) control:
Class: Crop Pest, Weed, and Disease Control Origin: Synthetic
Description: Glossy paper and colored inks are prohibited. Paper may only be used as a mulch or compost feedstock.
NOP Rule: 205.601(b)(2)(i) & 205.601(c) As herbicides, weed barriers, as applicable: Mulches. As compost feedstocks: Newspaper or other recycled paper, without glossy or colored inks.
I definitely recommend removing any colored newsprint and glossy inserts that come with the average daily paper. I personally wouldn’t use newspaper mulch in a bed where food is being grown, but perhaps I am exceedingly cautious. You might want to be aware that nanotechnology is now being used in some printing inks, and in some glossy ads (such as Macy’s) which are scent-microencapsulated (I found out about this because I complained to Seattle Times management about the odor). This link to Ink World magazine discusses the use of nanotechnology in printing. Harvard’s School of Public Health explores the environmental and human health implications of nanotechnology in printing.
Grist Magazine has also addressed the related issue of using newspaper in compost.