From: Debra Jacobson (firstname.lastname@example.org)
Date: Thu, 08 Aug 2002 08:46:44
In reply to your question, newspapers are typically printed with offset lithographic printing processes or some flexographic printing processes. Approximately 1% of the entire flexographic printing market is used to print newspapers.
In terms of metals contents, most heavy metals were phased out of printing inks in the 1970's when the Environmental Protection Act and RCRA began to impact the use of these materials. In the 1980's the technology to develop pigments while achieving color standards continued to improve and the remaining heavy metals were phased out of inks. There are a few exceptions to trace amounts of metals blended in ink due to the metal compounds are in the pigments that give the ink the desired color. These metals blended into the ink do not necessarily mean the material would be considered hazardous nor are the metals in a volume that would render the waste hazardous.
Substitutes for hazardous metal compounds have been developed for materials using copper, barium and nickel. These are the most common metals blended in compound form into ink pigments. Copper is commonly found in blue, green, violet and some red inks. Barium is commonly found in orange and red inks. Nickel is found in yellow inks. Chromium and lead, at one time, were blended into yellow ink. However substitutes have been developed. There are a few cases where very minute amounts (less than 1%) chromium compounds and lead compounds are blended into SPECIALTY inks. These are used in very minute quantities and not commonly found.
If you are referring to the ink's ability to release metals from the actual newsprint, the response to this question is that there is no evidence of measurable leaching of metals (or other hazardous materials for that matter) from the ink. The pigments, once the ink is cured into the newsprint, are encapsulated in the ink resins and binders, as well as into the fibers of the paper. In other words there should be no concern over using newsprint (both colored and black and white) are perfectly safe to use in compost, etc.