Hey Mr. Green,
Are the colors in newsprint, junk mail, and advertisements--especially the glossy ones--made from heavy metals like lead and mercury, or are they vegetable dyes and safe to mulch into soil? --Francis in Mt. Shasta, California

Mr Green answers:
Both black-and-white and colored newsprint are safe to use for mulch or compost. One study of newsprint's use as animal bedding found that it contained fewer heavy metals than plain old straw. But glossy magazines and colored supplements and inserts, which are often produced with heavy-metal-based dyes, should not be used in your garden. (Although Sierra's printer uses soy-based inks, magazine pages do not break down effectively in compost.) Now you've heard it here from Mr. Green: Do not compost this magazine, nor mulch your veggies with its pages, even if they sound outrageous; recycle it with loving care, or archive it for curious heirs.