WASHINGTON — The Degradable Polymers Council has developed guidelines for biodegradable bags used in composting, a move that aims to bolster plastic bags against paper and help stave off legislative attempts to ban plastic from composting.
Michigan legislators last fall considered banning plastic bags from compost piles, and industry officials hope labeling products that meet DPC guidelines will allay consumer skepticism about the range of plastic bags that claim to be degradable.
DPC members adopted guidelines being considered by the Committee for European Normalization, a standard-setting body, said Frederick Scheer, chief executive officer of Biocorp Inc., a Los Angeles-based biodegradable bag extruder and a DPC member.
The standards were adopted to ``avoid any kind of trouble similar to the ones 10 years ago when chemical companies were playing with the words and announcing their products as biodegradable'' when they contained polyethylene that was not biodegradable, Scheer said.
The new guidelines say how quickly a bag must degrade to be labeled biodegradable or compostable. For example, no more than 10 percent of a bag's original weight can remain on a three-eighths-inch screen after 12 weeks of exposure.
Most companies that make genuinely degradable polymers will be able to meet the guideline, which ``is not established as a high barrier,'' said John Malloy, DPC staff director.
``It is established to say a bag should act a certain way in a compost pile. Nobody should have trouble meeting the standard,'' Malloy added.
However, bags that are not designed to be biodegradable will not meet the guideline, he said.
DPC is a unit of the Washington-based Society of the Plastics Industry Inc. All DPC member companies should be able to meet the guideline, said Graham Chapman, DPC vice chairman and vice president of technology for Novon International Inc., a Tonawanda, N.Y., maker of additives to biodegradable bags.
Degradable bags are usually 11/2 to five times more expensive than nondegradable PE bags, but they compete more with paper bags than with other plastic bags, he said.
``This will give people the satisfaction that plastic will work,'' Chapman said. ``That is something we've had to fight for a long time.''
Some industry officials also have said that local governments are skeptical of composting claims because some regular PE bags have been touted as biodegradable.
The Composting Council, based in Bethesda, Md., has given a generally good reaction to the guidelines and participated in recent DPC meetings about them, Chapman said. Composting Council officials could not be reached for comment.
Michigan's effort to ban plastic from compost piles was the most significant legislative activity recently, Malloy said. That push is dormant now, but could reappear, he said.