Paper and plastic

Starting on Monday, according to Editor and Publisher Magazine, the bags that your Star Tribune arrive in will be biodegradable, becoming the first newspaper in the country to do so, it says.

The bags, which feature water-soluble inks and non-lead-based color concentrates, are expected to degrade in 2-3 years in a landfill. Bags “floating” as litter in the environment are expected to degrade within a few months. Because the bags are conventional plastics, they can also be recycled.

The typical bags can last 100 or so years, according to a news release from the company that makes the bags:

First, triggered by oxygen, heat, sunlight, or mechanical stress, a proprietary additive causes the plastic to oxidize. The oxidative degradation breaks the polyethylene molecules into smaller sizes. Second, when the molecules are small enough, microorganisms (fungi, bacteria, etc.) digest the molecules, leaving only water, carbon-dioxide, and biomass, which are natural elements of nature. Results of tests at Willow Ridge Plastics, in Erlanger, Kentucky, confirm that bags manufactured by GP Plastics, containing a proprietary additive, will meet the specification of an oxo-biodegradable plastic.

A few years ago, some of the plastic bag makers — Glad, Mobil etc. — marketed plastic bags that they said would degrade in landfills. But there was a problem. They were hydro-biodegradable, which meant when they degraded, they emitted methane, a greenhouse gas. Oxo-biodegradable plastics do not emit methane.

(h/t: City Pages)