Sustainable Consumption

Plastic Bags: What About Recycling Them?

Today most shoppers at grocery stores and farmers’ markets carry home their fresh produce and other purchases in plastic bags. Plastic bags are also commonly used in most retail stores today, and few shoppers realize that the lightweight bags they take for granted cause serious environmental problems.

According to the Marine Conservation Society of the UK it takes 450 -1000 years for plastic bags to break down. Plastic in the marine environment never fully degrades. The end product of the break down, “plastic dust,” is ingested by filter feeding marine animals. The dust and the bio-toxins, such as polychlorinated biphenyls (PCBs) that the plastic dust accumulates, are passed up the food chain to fish and humans.

Biodegradable bags made of cornstarch and other degradable components do exist. However, they need air and light to break down, conditions which most landfills don’t provide. At best, biodegradable bags take months to years to break down, are more costly than plastic, and as a category comprise only a tiny fraction of the market. Some recycling coordinators predict that improvements in biodegradable bags may make them a more attractive and more affordable choice in the future.

Several chain markets and a few independent groceries offer a 1¢ to 5¢ cent per bag discount if customers bring their own bags. Safeway and Albertsons maintain collection bins for used plastic bags. In 2003 Safeway collected 7,000 tons of plastic grocery bags, pallet-wrap plastic, and dry cleaners’ bags. The plastic is sold to a company that makes Trex, lumber-like boards generated from plastic bags and “reclaimed pallet wood and waste wood.” Unfortunately, composite lumber made partly with plastic is not considered to be recyclable even though it may last a long time.

One grocery chain is selling very inexpensive reusable grocery bags made of plastic (non-woven polyethylene.) While these bags may encourage people to reuse grocery bags, they have significant drawbacks. They are estimated to last only two to three years; they are made of virgin (not recycled) plastic; they are not recyclable into more bags, and their plastic will likely be in the environment forever in one form or another. If you sniff these plastic shopping bags you may discover that they off-gas noticeably. In contrast, cloth bags of cotton or hemp will last for hundreds of shopping trips.

Some cities on the Peninsula collect plastic bags for recycling. The City of Palo Alto has collected plastic bags for recycling since mid-2002. In 2004 nearly 18 tons of plastic bags were collected.

Annette Puskarich, Recycling Coordinator for the City of Palo Alto points out that it is a misperception that recycling makes money. The broker who purchases recycled plastic bags from the City of Palo Alto pays the City $20 per ton for them only if they are baled. Considering the process of trucking the plastic bags to and from the recycling center and the expenditure of labor to handle and bale the bags, the preferred alternative to recycling plastic bags is not to use them at all, says Puskarich. She strongly recommends reusable cloth bags instead.

In 2004 San Jose collected 477 tons of plastic bags from a quarter of its single-family dwellings and all multi-family dwellings, according to W. McConkey, Public Relations Director of Green Team, San Jose’s recycling contractor. In contrast to Palo Alto and San Jose, Sunnyvale’s recycling program receives “very few” plastic bags for recycling, according to Solid Waste Contract Administrator Debbi Sargent, although information on plastic bag recycling is included on Sunnyvale’s web site. Several markets in Sunnyvale provide collection bins for used plastic bags.

Gloria Chan of San Francisco’s Department of Environment points out that San Francisco does not accept plastic bags in its single stream recycling mix and that at the present time they end up in landfill. She reports that plastic bags cause problems when they are incorrectly tossed into the single stream recycling mix and become tangled in the sorting machinery. When this happens the machines must be shut down to remove the bags. As in other cities, used plastic bags in San Francisco can be deposited in collection bins at certain grocery stores.

At the time of this writing San Francisco is considering a 17 cent surcharge on both plastic bags and paper bags at major supermarkets to encourage shoppers to use their own cloth bags. A study by the City of San Francisco determined that 17 cents is what it costs to handle each discarded plastic bag. If the surcharge is implemented, San Francisco may be the first city in the U.S. to introduce it.

The Berkeley Plastics Task Force says that plastic recycling programs may give people a false assurance concerning the benefits of recycling because processing used plastic can cost more than virgin plastic. Finding a market for used plastic is challenging, says the Task Force, because the manufacturers of virgin plastic strongly resist legislation requiring recycled content in their packaging products. Less expensive “…virgin resin [is] flooding the market,” thwarting the efforts of recyclers, says the Task Force.