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'Paper or Plastic?' The Eco-Friendly Answer is 'Neither - Reusable'
Paper or plastic grocery bags - which are better for the environment?
You probably think you know the answer. And you're probably wrong.
Paper bags are not necessarily better for the environment than plastic - despite many consumers' long-standing assumption that paper beats out plastic hands down when it comes to eco-friendliness.
"There definitely was a period of time when the message was, 'Choose paper over plastic,' " said Jenny Powers, a spokeswoman for the Natural Resources Defense Council. "That's not the way to view it."
Powers and other environmental experts now say the best choice is neither paper nor plastic - it's reusable shopping bags made of substances like cotton, hemp, nylon or durable mesh-like plastic.
"The ideal option is bring your own bag," Powers said. "Second choice is to ask for the type of bag that you know will be reused - plastic if you'll use it for holding trash, or paper if you will recycle it."
The question of the relative merits of various kinds of grocery bags sounds simple.
But in fact, scientists spend large amounts of time trying to nail down the environmental impacts of creating, transporting and disposing of products such as grocery bags - a process known as life cycle analysis.
The final answer depends on numerous details, including:
-- Whether the bags are made from recycled or virgin materials.
-- How far the raw ingredients and finished bags must travel before reaching consumers.
-- How much energy and water are used in the manufacturing process.
-- Whether bags that are labeled "recyclable" or "compostable" actually end up being recycled and composted, or just get dumped in the trash.
The stakes are high. Ninety percent of today's grocery bags are plastic. Californians alone use 19 billion plastic bags each year - 600 bags every second - according to the California Integrated Waste Management Board.
And fewer than 5 percent of plastic bags historically have been recycled, compared with 21 percent of paper bags.
Plastic bags are a particular problem in coastal regions like the Bay Area, where they often end up in rivers and oceans - poisoning or strangling marine life. Sixty to 80 percent of ocean debris is plastic, according to the Algalita Marine Research Foundation. And while plastic may gradually shred into smaller pieces, those fragments will persist and threaten sea life for up to 1,000 years.
But paper bags have other negative effects on the environment.
"If you're comparing a paper bag made from virgin timber with a plastic bag made with natural gas, the paper bag causes more global warming pollution, more biodiversity impacts and more water impacts," said Allen Hershkowitz, a senior scientist with NRDC who has worked on life cycle analyses for two decades. "If the paper bag is not recycled, it will generate greater carbon emissions during incineration than plastic would, or greater methane emissions if it is landfilled."
One thing is clear in every study that has been done: Reusable bags beat both paper and plastic on virtually all environmental criteria.
For instance, a 2002 Australian study concluded that someone using plastic grocery bags for a year would go through 520 bags and generate 6.08 kilograms of greenhouse gases, which contribute to global warming. Someone using paper bags would also go through 520 bags to generate 11.8 kilograms of greenhouse gases.
But a year's worth of reusable polypropylene bags - estimated at four bags, used twice a week - would generate less than 2 kilograms of greenhouse gases.
"The best thing is for people to be encouraged to take reusable bags," said Hershkowitz. "That's a truism everyone can agree upon."
Learn more about the environmental impacts
-- A Web site called Use Less Stuff, use-less-stuff.com, offers an easy-to-read summary of several European analyses of grocery bags.
A 2007 report by Los Angeles County summarizes some of the research on paper-versus-plastic at links.sfgate.com/ZBWC.
-- San Francisco's Department of the Environment offers another summary of bag analyses from Sweden and the United States at links.sfgate.com/ZBWB.
-- The 2002 Australian report can be found at links.sfgate.com/ZBWD.
E-mail Ilana DeBare at idebare@sfchronicle.com.
© 2007 The San Francisco Chronicle
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9 Comments so far
Show AllWe use paper bags to dispose of shredded documents. We shred documents to thwart ID thieves. We use paper bags so the shredded confetti doesn't fly all over the "environment" on recycle day. We use plastic bags for cleaning the cat box. If we switched to reusable grocery bags, how would we dispose of confetti and kitty poop?
It won't make a difference cloth or plastic until they discover an easy way to get airfreshioner off of cloth.
nostra, you could switch to flushable/compostable cat litter made with wheat or corn. Yeah, I know it uses an agricultural product, but the mining of clay litter has a lot of environmental problems, and it ends up in landfills forever, along with the plastic bags it's wrapped in.
Look at the quintessential illustration of the eco-friendly example in the picture above.
Take note consumer, I'd hate for you to be caught using some crappy old tote bag you dug out of your closet.
Pacific Trash Vortex, hot topic over the last several y ears.
http://en.wikipedia.org/wiki/North_Pacific_Gyre
Powers and other environmental experts now say the best choice is neither paper nor plastic - it's reusable shopping bags made of substances like cotton, hemp, nylon or durable mesh-like plastic.
They now say? Now?!? What a stupid thing to even print. That's always been a better choice. Anyone who's surprised by that startling revelation needs a good thwack to the head.
I've got this nifty cloth bag distributed by the EPA (that's the Taiwan EPA, by the way, though it's hardly more effective than the US's) with an EPA logo on one side and that curved-arrows recycle logo on the other. I'm rather fond of it. It's gotten to the point now where I actually had to purchase some plastic bags for use at home for trash, because I've run out of everything else.
Here, the Taiwan government made a small attempt at discouraging the rampant use of plastic (paper products don't like the subtropical humidity, and this is after all an island choked to the gills with plastic everything) bags a while ago: now you are asked if you even want a bag when you shop, and charged NT$2 (about 6 cents) if you say yes. Of course, expensive stores still want you to give them free advertising by carrying around their obscenely thick logo-printed paper bags, and people can't resist the status they think toting a paper bag with "Chanel" written on it confers to them.
For shopping, a fee for a bag isn't a bad idea, and whether people just don't want to pay or not, I see an awful lot of shoppers bringing their own totes or using empty cardboard boxes stashed in corners outside grocery stores. But as a way of dealing with the plastic bag problem in general, it hasn't really worked very well, and in a bizarre move, the Taipei mass transit folks (they run the subways and franchise bus service) recently installed stupid boxes full of long plastic bags for people to sheathe their wet umbrellas as they board a train. More plastic bags? And nobody re-uses them once their wet: it's stupid.
People in Europe use BASKETS woven from plant fibers to haul their groceries home, and also mesh bags (which can be crumpled up very small when not in use).
That said, it seems to be a trend in Ukraine to people to use identical plastic bags with a pseudo fashion-designer's logo. These get re-used for as long as possible. Not as eco-friendly, but it says a lot about people's desire for status!
two rivers: (btw, thanks for joining: five comments seemed awfully lonely for so many days!)
Woah...a mesh bag. Even better!!! Now I'm thinking about taking a hole punch to my EPA bag. Sad to hear about how widespread this crazy status hallucination is, but it's really no surprise. When the majority are comprised of people pissed off about how the CURRENT majority have screwed up our planet, then maybe that trend will reverse itself.
Golly...I wonder if I stood on streetcorners and handed out free mesh bags made of recovered monofilament from the North Pacific Gyre by Taiwanese aboriginals paid a living wage from a Greenpeace grant...yeah, I'm dreaming, but I'd love to make a dent here on this island: a dent in peoples' consciousness.
I am giving reusable bags to my whole family for Christmas (including produce bags) and re-usable water bottles and CF light bulbs. We can't all do everything, but we can all do something (as the saying goes...)
I never use a bag if I don't have to when shopping. If I buy a small item or a few, and can carry them myself, I say "no thanks," when they ask me for a bag.
How many of us buy one thing in a store, and walk out of there with a paper or plastic bag? Don't take one. You don't need it.