Paper or plastic?

Circumstances have brought me back to the grocery store bags issue. I freely admit that I originally assumed that paper bags must be more efficient than plastic ones, and that I was wrong. A Google search on paper vs. plastic brings up many websites, but a study by Franklin and Associates (albeit in 1990) summarized by the Institute for Lifecycle Environmental Assessment, seems to be what most people cite.

Here are some of their conclusions. Note that in making their comparisons, Franklin and Associates examine the amount of energy needed to produce the bag, and the pollutants resulting from the bag throughout its lifespan. Also, a single plastic bag carries about 2x the amount of goods that go into a paper bag. However, stores typically use improper bagging techniques with plastic bags (update: I take this to mean that they double-bag and possibly don't put as many items in the bag as they could), so to be as realistic as possible, all of the evaluations below compare 2 plastic bags to 1 paper bag. You'll see that even using the 2-to-1 plastic-to-paper ratio, plastic comes out as less energy intensive.
  • According to the EPA in 2002, Americans currently recycle 0.6% of plastic bags and 19.4% of paper bags.
  • A single paper bag uses the energy equivalent of 550 kJ of wood as feedstock. It also uses 500 kJ of petroleum and 350 kJ of coal for process energy. The total amount of energy used by a single paper bag is 1,680 kJ.
  • Two plastic bags use 990 kJ of natural gas, 240 kJ of petroleum, and 160 kJ of coal. The energy used for two plastic bags is 1,470 kJ. Two plastic bags use 87% the amount of energy used by one paper.
  • All of these calculations take into account current recycling rates, and paper bags need a recycling rate of at least 50% to be more energy efficient than twice the number of plastics.

  • Plastic bags, having less mass than paper, produce less solid waste. At current recycling rates two plastic bags produces 14 g of solid waste while one paper creates 50 g.
  • Atmospheric waste and waterborne pollutants are also higher for paper bags.
Well, OK. If it were the case that paper and plastic were truly equal in every other respect, then it would seem clear that plastic is the better option. But the study (at least as summarized by ILEA) does not discuss two important points: Paper bags biodegrade, and trees are a renewable resource (though a slow one) whereas the amount of petroleum and natural gas in the world is finite. Not being an economist, I don't know how to factor these issues into the equations, but I wonder if they'd make a difference.

Still, there's only one real solution to the answer: Use cloth bags instead of either paper or plastic! (And for those of you who drive cars, you could leave about 4 of them in your car so that you have them when you find yourself at the grocery store.)

(And for kicks, check out this discussion on Gothamist about how New Yorkers view the abuse of plastic bags.)

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i saw a nice lady last week, bring two folded paper bags back to the market, just put them in the cart, shop, and they used them again at the checkout. this was at trader joe's where they actually reward such things. if you bring your own bag you go in a drawing for free groceries.

that seemed a lot simpler, and less silly, than other recycling schemes.

Can paper bags be added to compost? If not, you can always use them to start log fires.

I've thought about stuffing plastic bags behind gyp board as insect-proof insulation.

Yes, paper bags can be composted as long as there's not too much ink on them.

One of the things I read when googling around (but I don't have the link here) explained the process of how paper bags were recycled, and it seemed pretty chemical-intensive because they have to remove the ink from the fibers before the paper can be reused.

As for uses of plastic bags (other than kitty litter and dog poo, cleaning up after your children, and garbage bags for the little trashcan in your bedroom), you may find many suggestions at Frugal Living on About.

i saw that somone had molded a waste basket with "ears" so that it easily held plastic grocery bags, as trash bags ... looking ...

Second paragraph is confusing. Is it possible you mean "1/2" where you have "2x"? Or that you have the two types of bags reversed in that sentence? The "double bagging" part doesn't help.

Bob Munck--OK, I reworded. Is it clearer now?

Yes, it's clear what you mean. It doesn't correspond with my experience, but that's just anecdotal. I seem to end up with about 20 plastic bags from a single shopping trip, each with 2-3 items. Except when I go to Trader Joes, where I get a dozen items per (doubled) paper bag. Maybe that's why I was confused.

There was a fairly graphic description in a book I read recently about a forest on the down-wind side of a large city (Mexico City, I think). The trees were essentially plated with wind-blown plastic bags, and dead.

I think the math might be a little bit off. While "Americans currently recycle 0.6% of plastic bags and 19.4% of paper bags, " the choice for the individual is different. The 50% threshhold for paper should only apply to the person making the decision. Having said this the .6% for plastic should also be taken into account.

The short answer is: if you are going to recycle in either case, the plastic is better. If you would only recycle paper (more than 50% of the time), then paper is better. And, if you are going to recycle neither, then plastic is again better.

For another perspective on paper versus plastic, see Trashing the Oceans.

Although most plastic bags go to landfills, sometimes they end up in the Pacific Gyre....

Thanks, Ianqui. I will say that since my community doesn't accept plastic bags for recycling (though of course we save them for reuse), but DOES require paper and cardboard to be placed on the sidewalk in paper bags, I think the scale is still tipped in favor of paper for me. Even if I start bringing some canvas bags to the store (anyone want to factor in the production costs of cotton canvas? I'm kidding, but no choice comes without some cost...), I'll still need some paper bags if I want to continue recycling paper and cardboard.

It seems like this is yet another example of the difficulty of trying to reduce one detail of our consumption in the context of a society that's totally built around consumption and disposal.

But, on an upbeat note, Whole Foods is selling compact fluorescents now, so I brought some of those home in my paper bags...

Well I am not sure about where everyone else shops, but in my local supermarket they have paid people bag your groceries. They use plastic bags as if they were going out of style. The result is that a grocery haul that would fit in 2 paper bags requires about 8-10 plastic bags. If I were to be able to bag my own, then I could get the ratio down to about 1:2.5 but a plastic bag will not handle the same amount of stuff as a paper bag. Add stuff with a sharp corner or canned goods and the plastic bag could send your food tumbling across the parking lot. Plastic is good for meat however.

Also, I Don't have a dog so don't need a crap-mitten. Paper is good for cooling cookies on, covering books, crafts, wrapping presents, etc. I do use the plastic ones for covering my bike seat in the rain. Renewable, the paper wins out for me. The canvas bag idea seems ideal though.

The university where I work has what they call the R4 program: Recycle, Reuse, Reduce, Rebuy. It seems to me that the three Rs after Recycle are key. To reduce our energy footprint we need to get to a point where we aren't producing stuff (bags, etc.) that is used once and then energy must be expended to make it usable again. My wife and I use canvas bags for our groceries for that reason.

Why not use supermarket plastic bags instead of trash bags? True, they're not as big, but if we're aiming to throw out less garbage, that's a *good* thing. It also saves money.

Paper bags aren't as useful, because they're not water/air resistant. The only use I can really find for them is storing paper/cardboard for recycling.

Check at the supermarket where you buy your food. Wegman's (a central NY store) has a recycling bin near the front service counter, and near the enterances. You just have to remember to bring the bags back.

Another problem with the supermarkets and bodega's in NYC is that the quality of bags that they use is so poor, that the have to use the equivalent of 2-3 of their bags to hold the amt of food that one bag holds normally. (at least at the "Fine Fair" - yes, I lived in a crappy neighborhood)

Actually, anonymous, my community makes you pay for special trash bags with the town stamp on them. You make more garbage, you use more bags, you pay more money. I have no idea if our community has cut down on its waste since the program went into effect, but it certainly provides a good economic incentive to do so.

I've actually been stweing about the paper vs. plastic issue and oil supply since frequenting this site. I usually try to (politely) insist on bagging my own groceries. I use plastic (the only option where I shop, unfortunately), and then I reuse the plastic bags for trash disposal. By minimizing the number of bags coming in, I keep a rough equilibrium and have a fairly constant bag supply (once or twice I have even almost run out of bags). I use a small basket in the kitchen to encourage frequent emptying.

I'm not sure how it will change if oil supplies make plastic bags more expensive, but I figure that is still a ways down the road--or, if it becomes a Kunstlerian nightmare, that will be among the least of my worries.

Okay I googled "do plastic bags degrade?" here are some excerpts:

"They take between 20 [litter] and 1,000 [landfill] years to break down and are able to float and blow long distances within our environment. While they exist in our environment, they choke, suffocate, and cause intestinal blockage in thousands of animals including birds, fish, whales, turtlesÂ… the list goes on."

According to the World Wildlife Fund, "more than 100,000 whales, seals, turtles, and birds die every year as a result of plastic bags." The Australian government reports that "on 24 August 2000, a Bryde's whale died in Trinity Bay, 2 km from central Cairns. An autopsy found that the whale's stomach was tightly packed with plastic, including supermarket bags, food packages, bait bags, three large sheets of plastic, and fragments of garbage bags. There was no food in its stomach."

Every year more than 6 million tonnes of rubbish is dumped into the world’s oceans. In every square mile of ocean it is estimated that there are over 46,000 pieces of plastic.


"It's not one that the paper-bag people like to hear. In a dry landfill, paper bags don't degrade any faster than plastic bags. In a normal, well-run landfill, paper bags do not biodegrade any faster over at least 40 years than plastic."

The problem with paper is that it's fatter, he explains.

"Paper bags are much bulkier than plastic, so they fill up more landfill space," Rathje says. "They're three to five times bulkier than plastic, and you can see that yourself at the grocery. Landfills are closing down because they're full. From that perspective, plastic is much better than paper."

A quote from the Dancing Rabbit episode of 30 days: 30 minutes use from store to refridgerator. 1000 years to decompose. Its overengineered.

In 2001, Ireland consumed 1.2 billion plastic bags, or 316 per person. An extremely successful plastic bag consumption tax, or PlasTax, introduced in 2002 reduced consumption by 90%. Approximately 18,000,000 liters of oil have been saved due to this reduced production. Governments around the world are considering implementing similar measures.

a blog about plastic bags:
a website:
a source for biodegradable bags:

On paper degradation: People who examine landfills to study social trends, etc., routinely rely on newspapers, which don't degrade, to "date" the garbage strata.

The problem, as I understand it, is that the paper isn't exposed--it gets covered up pretty quickly in the landfill, so there's no chance for rain, temp. changes, etc. to speed up the process.

Do plastic bags MELT? Could one design a little stand-alone, stovetop, or microwave oven appliance that would incrementally add a few bags to a growing solid brick of plastic? I wouldn't think that a year's worth of plastic bags would be more than a dozen cubic inches of plastic, and maybe some industry would be willing to accept or buy that brick for ... wait for it ... reuse.


If plastic prices are going to shoot through the roof, maybe the block of melted bags will make you rich.

OK - here is my drill.

I shop for daily "stuff" about 2X a month. This is 1 fully loaded (bulging) grocery cart. I bring the same three, xtra large canvas bags, and put them in my car. At checkout, I have them just put my stuff back in a cart. This lets me pack my own stuff, and insures eggs and bread and such aren't creamed by some dont-give-a shit high school kid. At my car, I pack the stuff in the canvas bags, and then carry them into the house. I unpack the stuff, and stick the bags between the fridge and the wall, in that totally useless space.

I have had these three canvas bags for over 10 years, and I am glad to do it.

If you have a newer car with one of those "cargo nets" included, you don't even need to bring bags - just pop in the net and stick your stuff behind it to get it home. Put a few boxes in the back seat and pop them in there. The fact is that grocery bags are a CONVENIENCE. Shopping bags were originally cloth or canvas and designed for people to BUY and then use for years. In europe, the shopping bag is still around, and many people use it to buy their dinner supplies every night at the corner market, on the way home. The same is true in much of the rest of the world - the cloth or canvas bag is used to shop at the local markets. Our disposable society changed this during the early part of the industrial revolution.

As you drive the freeways around my town, you can see "dirt devils" picking up the plastic bags everywhere - it is not a very attractive sight. You can see them lining every ditch near the freeways, and each time it rains they get washed into some unknown part of the local ecosystem. Since plastic needs UV light to degrade with any kind of rapidity, burying them insures their enjoyment by future generations. I am sure they get buried somewhere in the ecosystem when they wash away, to be "discovered" later by some future generation.

Paper, in and of itself, is a hugely energy intensive process. Wood has to be broken down to its simplest form from logs, bleached, pressed, dried, and chemically treated. Even recycling paper uses inordinate amounts of chemicals and energy to break down the recycled mass into watery pulp again. After this the recycled pulp is bleached, but only because people require bags that "look new" or that "look nice". Unbleached paper is basically grayish brown and mottled, and doesn't let advertisers print on it effectively. If you examine each process, cloth requires less energy input than paper in the first place.

The bottom line for everybody is that if you want to conserve energy, bring your own bags.

If you want to conserve petroleum, bring your own bags.

If you want to help maintain the ecosystem, bring your own bags.

If you want to do something sustainable, bring your own bags.

If you want to be progressively retro, bring your own bags like your great-grandparents did.

If you hate ubiquitous advertising on every little thing, bring your own bags.

If you want to be a trendsetter, bring your own designer bags.

If you want to prepare your children and set a sustainable example, bring your own bags.

Plastic bags exist that are made from renewable resources and are also biodegradable. I have no idea what the energy costs are, however. The downside is that the bags are made from corn (maize), which is a very fossil fuel intensive crop. See

I keep a string bag and a sack suitable for a quart of beans in my backpack - string bags are small and hold much.

On the other hand, I like having some plastic carrier bags for occasions of drippy garbage. I can't compost everything.

I've seen some developing countries just festooned with broken plastic bags, and it was because they didn't have garbage pickup yet - other than pigs - the plastic bags were the only thing neither biodegrading nor being reused. Plenty of UV; slow breakdown.

I wonder how the energy economics would change if the paper bags were made from (say) hemp fibre rather than wood pulp? AFAIK, wood pulp is the least efficient way of making paper...