On the other hand, cellulose insulation production—because of its low-tech nature—is an ideal reuse for discarded newspapers. Though ink is used in the printing process, de-inking is not required for producing cellulose insulation. Modern printing technology has for the most part substituted soy-based inks for petroleum based black inks. Color inks cause the main concern regarding the ink content in recycled newspaper. Heavy metals such as cadmium and lead were used in the production of color print when first introduced in the early ’80s. By then, the dangers posed by heavy metals to human health were well known and their use has since been banned.
Another appealing aspect of using recycled newspaper to produce cellulose insulation is the low energy or aka, EE required to produce it. Based on a 1991 study cellulose insulation, inclusive of its fire-retardant chemicals (20 percent by weight), requires only a fraction of the EE of other common insulation materials: