Paper Bags or Plastic Bags? Everything You Need to Know
by Collin Dunn, Corvallis, OR, USA on 07. 9.08
Paper or plastic bags: which is better?
It's an age old question, when it comes time to check out when grocery shopping: paper bag or plastic bag? It seems like it should be an easy choice, but there's an incredible number of details and inputs hidden in each bag. From durability and reusability to life cycle costs, there's a lot more to each bag than meet the eye. Let's take a look behind the bags.
Where do brown paper bags come from?
Paper comes from trees -- lots and lots of trees. The logging industry, influenced by companies like Weyerhaeuser and Kimberly-Clark, is huge, and the process to get that paper bag to the grocery store is long, sordid and exacts a heavy toll on the planet. First, the trees are found, marked and felled in a process that all too often involves clear-cutting, resulting in massive habitat destruction and long-term ecological damage.
Mega-machinery comes in to remove the logs from what used to be forest, either by logging trucks or even helicopters in more remote areas. This machinery requires fossil fuel to operate and roads to drive on, and, when done unsustainably, logging even a small area has a large impact on the entire ecological chain in surrounding areas.
Part way between trees and paper bags. Photo credit: Sally A. Morgan—Ecoscene/Corbis
Once the trees are collected, they must dry at least three years before they can be used. More machinery is used to strip the bark, which is then chipped into one-inch squares and cooked under tremendous heat and pressure. This wood stew is then "digested," with a chemical mixture of limestone and acid, and after several hours of cooking, what was once wood becomes pulp. It takes approximately three tons of wood chips to make one ton of pulp.
The pulp is then washed and bleached; both stages require thousands of gallons of clean water. Coloring is added to more water, and is then combined in a ratio of 1 part pulp to 400 parts water, to make paper. The pulp/water mixture is dumped into a web of bronze wires, and the water showers through, leaving the pulp, which, in turn, is rolled into paper.
Whew! And that's just to make the paper; don't forget about the energy inputs -- chemical, electrical, and fossil fuel-based -- used to transport the raw material, turn the paper into a bag and then transport the finished paper bag all over the world.
Paper recycling plants, like the one shown above, is the best place for bags to go when you're done with them.
Where do paper shopping bags go when you're done with them?
When you're done using paper shopping bags, for shopping or other household reuses, a couple of things can happen. If minimally-inked (or printed with soy or other veggie-based inks) they can be composted; otherwise, they can be recycled in most mixed-paper recycling schemes, or they can be thrown away (which is not something we recommend).
If you compost them, the bags break down and go from paper to a rich soil nutrient over a period of a couple of months; if you throw them away, they'll eventually break down of the period of many, many years (and without the handy benefits that compost can provide). If you choose the recycle paper bags, then things get a little tricky.
The paper must first be re-pulped, which usually requires a chemical process involving compounds like hydrogen peroxide, sodium silicate and sodium hydroxide, which bleach and separate the pulp fibers. The fibers are then cleaned and screened to be sure they're free of anything that would contaminate the paper-making process, and are then washed to remove any leftover ink before being pressed and rolled into paper, as before.
How are plastic bags made?
Unlike paper bags, plastic bags are typically made from oil, a non-renewable resource. Plastics are a by-product of the oil-refining process, accounting for about four percent of oil production around the globe. The biggest energy input is from the plastic bag creation process is electricity, which, in this country, comes from coal-burning power plants at least half of the time; the process requires enough juice to heat the oil up to 750 degrees Fahrenheit, where it can be separated into its various components and molded into polymers. Plastic bags most often come from one of the five types of polymers -- polyethylene -- in its low-density form (LDPE), which is also known as #4 plastic.
How does plastic bag recycling work?
Like paper, plastic can be recycled, but it isn't simple or easy. Recycling involves essentially re-melting the bags and re-casting the plastic, though, according to the U.S. EPA, manufacturing new plastic from recycled plastic requires two-thirds of the energy used in virgin plastic manufacturing. But, as any chef who has ever tried to re-heat a Hollondaise sauce will tell you, the quality isn't quite as good the second time around; the polymer chains often separate break (thanks to reader MaryBeth for noting the difference between "separate" and "break" -- the former implies that the chains can come back together, which they can't), leading to a lower-quality product.
What does that mean to you? Basically, plastic is often downcycled -- that is, the material loses viability and/or value in the process of recycling -- into less functional forms, making it hard to make new plastic bags out of old plastic bags.
What about biodegradable plastic bags?
Biodegradable plastic is a mixed bag (pun intended) as well; while biopolymers like polyhydroxyalkanoate (PHA) and Polylactide (PLA) are completely biodegradable in compost (and very, very, very slowly -- if at all -- in a landfill) and are not made from petroleum products, they are often derived from our food sources.
The primary feedstock for bioplastics today is corn, which is rife with agro-political conflict and often grown and harvested unsustainably; because of these reasons, and because it competes with food supply, it is not likely to be a long-term solution in the plastics world.
Plus, some bags marked "biodegradable" are not actually so -- they're recycled plastic mixed with cornstarch. The cornstarch biodegrades and the plastic breaks down into tiny little pieces but does not actually "biodegrade," leaving a yucky polymer mess (if in small pieces). The only way to avoid this? Look for 100% plant-based polymers, like the two mentioned above.
So, while it's good to have the alternative (and to recognize the innovation it represents), bioplastics aren't quite ready to save us from the paper or plastic debate.
Paper bags hold more stuff, but plastic bags use less energy during production and recycling. Photo: Getty Images
Paper or plastic: A look at the facts and numbers
Further insight into the implications of using and recycling each kind of bag can be gained from looking at overall energy, emissions, and other life cycle-related costs of production and recycling. According to a life cycle analysis by Franklin Associates, Ltd, [pdf] plastic bags create fewer airborne emissions and require less energy during the life cycle of both types of bags per 10,000 equivalent uses -- plastic creates 9.1 cubic pounds of solid waste vs. 45.8 cubic pounds for paper; plastic creates 17.9 pounds of atmospheric emissions vs. 64.2 pounds for paper; plastic creates 1.8 pounds of waterborne waste vs. 31.2 pounds for paper.
Paper bags can hold more stuff per bag -- anywhere from 50 percent to 400 percent more, depending on how they're packed, since they hold more volume and are sturdier. The numbers here assume that each paper bag holds 50 percent more than each plastic bag, meaning that it takes one and half plastic bags to equal a paper bag -- it's not a one-to-one comparison, even though plastic still comes out ahead.
It's important to note that all of the above numbers assume that none of the bags are recycled, which adds a lot of negative impacts for both the paper and plastic bags; the numbers decrease in size (and the relative impacts decrease) as more bags are recycled. Interestingly, the numbers for paper bag recycling get better faster -- the more that are recycled, the lower their overall environmental impact -- but, because plastic bags use much less to begin with, they still ends up creating less solid and waterborne waste and airborne emissions.
Paper and plastic bags' required energy inputs
From the same analysis, we learn that plastic also has lower energy requirements -- these numbers are expressed in millions of British thermal units (Btus) per 10,000 bags, again at 1.5 plastic bags for every one paper bag. Plastic bags require 9.7 million Btus, vs. 16.3 for paper bags at zero percent recycling; even at 100% recycling rates, plastic bags still require less -- 7.0 to paper's 9.1. What does that mean to me and you? Plastic bags just take less energy to create, which is significant because so much of our energy comes from dirty sources like coal and petroleum.
The best way to go? A reusable bag, not a plastic bag. Anya Hindmarch's wildly popular "I am Not a Plastic Bag" tote is helping give the reusable bag some sex appeal.
Paper bags or plastic bags: the conclusion
Both paper and plastic bags require lots and lots of resources and energy, and proper recycling requires due diligence from both consumer and municipal waste collector or private recycling company, so there are a lot of variables that can lead to low recycling rates.
Ultimately, neither paper nor plastic bags are the best choice; we think choosing reusable canvas bags instead is the way to go. From an energy standpoint, according to this Australian study, canvas bags are 14 times better than plastic bags and 39 times better than paper bags, assuming that canvas bags get a good workout and are used 500 times during their life cycle. Happy shopping!
Plastic bags are getting banned more and more. Read on in TreeHugger...
TreeHugger Picks: Ban the Bag
IKEA Bans Plastic Bags for Good
China Launches Crackdown on Plastic Bags
China’s Plastic Bag Ban is Working, So Far
San Francisco To Ban Plastic Shopping Bags
Whole Foods Bans the Bag
Bag Ban Phase 2: All Retail Stores
Wait for Us! Australia Wants to Ban Plastic Bags Too
Ban or No Ban: The Debate over Plastic Bags in LA (UPDATED)
More about reusable bags and shopping bags
Q&A: Retail Carry Bags - Paper or Plastic?
I'm Not an Ethical Plastic Bag
Anya Hindmarch's Carrier Bag
The Mini Maxi Shopper: the Reusable Bag you won't Forget
Reusable Shopping Bag Madness in Australia
Bring Your Own: Reusable Bags , Cups & More
Minimalist/Modernist Reusable Tote Bags
Bags of Change: Carrot Better Than Stick
I wish Whole Foods (and other stores) had gone one step further and simply banned both paper and plastic. So now I see a bunch of people leaving WF with tons of paper bags.
I gave up non-reusable bags two years ago. I usually walk to the grocery store or other stores and take public transit anywhere farther, and it is so much better not having to worry about my bags breaking. Environment aside, on sturdiness alone the transition to reusable bags is worth it.
The only exception is take-out. I am not yet ready to give it up (mostly because although I thoroughly enjoy cooking, I don't currently have a kitchen, so cooking- and washing dishes in particular- is unusually difficult). But by the time I see my food it is already in a bag, sometimes a paper bag inside a plastic one. It makes me wince to see it, but I do recycle them and I try my best to reuse them too. And when eating out I try to eat at the restaurant whenever possible, but sometimes I can't.
After living in Europe for three years, I bought my own bags for the US too. I love them, and they hold more/are of higher quality than the alternatives! I even take them to clothing stores.
The main WholeFoods in Austin is "experimenting" with no bags at the checkout. You have to bring your own or buy their reusable bags.
I've been using long-handled canvas totes for groceries for 5 years, since moving into an apartment with on-street parking. I can sling many canvas bags full of groceries onto my arms/shoulders and carry them all in one trip. (I'm pretty strong.) Much better than locking up the car, bringing in a load, heading back out, loading up again, etc.
But it's the strength of canvas bags that is tops. I would flinch whenever I'd see the grocery store bagger put only 2 or 3 items in each plastic bag because they would rip otherwise.
Great post, I've always wondered about this! I think David is right about Whole Foods but just banning the plastic was at least a good step and might prepare shoppers to make the move to canvas. Plus, even I still forget my bags sometimes so it's nice to have something available. If only they charged money to use the paper bags, I think people would start remembering their own.
Great post, I've always wondered about this! I think David is right about Whole Foods but just banning the plastic was at least a good step and might prepare shoppers to make the move to canvas. Plus, even I still forget my bags sometimes so it's nice to have something available. If only they charged money to use the paper bags, I think people would start remembering their own.
what do you do if you have dogs and no yard. I have lots of great canvas bags but if I used them all of the time I would have nothing to clean up after my dogs. I have seen supposedly ecological pooper scoopers but they all have fancy packaging and such which seems counter effective.
I read in a SMH article that plastic bags are not so evil- bags are made from a byproduct of processing natural gas which would otherwise go to waste; they prevent all the other bits of rubbish from going everywhere and act as a stabiliser for the ground when put in landfil.
Treehugger thoughts?
( http://www.smh.com.au/news/environment/bag-ban-carries-no-weight/2008/03/05/1204402553654.html?page=fullpage#contentSwap2 )
I've started taking a couple of those lightweight Glad plastic containers(for fast food or doggie bags or donuts from the grocery store), a big cup (again for fast food or 7-11), a few strong bags (for groceries) and a few small bags (for fruit and veggies) and a small facecloth to dry my hands in the washroom.
It's not difficult to do.
I think banning plastic / paper bag use at stores is not the answer.
Now if municipalities, states, or countries imposed a hefty (no pun intended) tax for each paper or plastic bag used, that might be incentive enough for consumers to switch to reusable bags.
Call it a garbage impact fee. Retailers and grocers are taxed for each plastic or paper bag they hand out, and they in turn charge their customers for each bag they use.
While I totally agree that the best option is to take a proper reusable bag shopping (or not use a bag if you only have a couple of items and don't really need one).
I just took a look at the paper bags I have here in the kitchen (which I keep for holding composting materials), and both the Safeway and Lucky ones claim to be 35%-40% made of post consumer recycled material. How does that change those numbers above which seem to assume paper bags made entirely from new paper?
Also, there are implications beyond the energy cost that need to be included in the equation too. I suspect that paper bags are more likely to be recycled than plastic ones (especially since few cities allow plastic bags to be dropped in the blue cart). The post consumer impact of a plastic bag thrown in the landfill, or left to find its way into the ocean, is much higher than a paper bag.
I've always wondered about this and could never decide what was better... Six months ago I came to Holland, and you have to buy your plastic bags here... So you're more likely to re-use your bags over and over... Which I think is the best way to go! Plus if you're on a bike, a canvas bag is much easier to hold onto!
Odessa, Texas is the place where all the old plastic bags blow to die. Everywhere you look while driving through; bags stuck to fences and tumbleweeds. It's very disturbing. I think they also collect around the oil rigs that are everywhere, too. Its very sad I think.
City of Seattle is trying to jump on the band wagon with their own twist - adding a 20 cent fee for use of each paper or plastic bags at checkout (grocery, drug store and such to start). I attended the City Council meeting last night (timely article). It was packed - mostly by supporters. The biggest concern is the impact on lower income shoppers. The City said they'll provide a reusable bag to every household and several to those with lower income levels. The few grocery/retail representatives there that I heard seemed more concerned about the administration of a "per bag" fee and asked that it be a "per transaction" fee. Interesting. I would think that okay, if the transaction fee covered the average bag use of probably 3-4 bags (including one of them being double bagged of course).
One of folks I attended the meeting with estimated that her family was using over 1000 bags a year from grocery and drug stores before purchasing her 5 reusable bags.
I'm really excited about this ban. I'd think the conversion rate from non-reusable bag shoppers to using reusable bags will be huge - maybe 80% within a year of implementation. And for those who are morally or otherwise against the fee ... they can drive to the next city over and spend more on gas than they would the transaction fee.
Hi,
It's not as far-reaching as decided in China as mentioned in this blog, but you can't get any plastic bags in the major supermarkets in Belgium. You can buy reusable bags or pliable boxes instead.
Eddu
Bags.. Who would of thought that this would still be an issue? My husband I an realized the simplicity yet complexity of the problem last year and started educating schools and towns in NJ on reusable bags, recycling of plastic bags, and recovery programs. More and more we are seeing people use reusable bags in our area and we hope this habit becomes more main stream. Props for treehugger for not letting this issue fall of the table.
www.goriseup.com
We are more than a bag company!
Unless they are made from organic cotton, canvas bags are less sustainable than synthetic fabric bags.
I love this lame excuse people have about forgetting reusable bags in the car. Uh, how about walking back out to your car and getting them, lardasses.
My entire family uses canvas bags,we love them.Canvas is stronger and more comfortable to carry,plus you never have a bag break like plastic and paper.
I prefer to carry my own re useable bags each time!
www.FireMe.To/udi
About paper:
There are forests of trees grown just for paper. There is no clear cutting as the author implies in these forests. In some cases, there are 2 trees or more planted for every one harvested.
Also, you know those forest fires in California? Unmanaged forests naturally thin themselves. So either nature does it [and we try to stop it for some reason every year] or we do it.
Renewables are part of a life cycle.
Clear cutting and deforestation is bad, but cutting down trees for paper is no where near as bad as the author makes it out to be.
I use the Granite Gear Air Grocery Bag
http://www.granitegear.com/products/accessories/airgrocerybag
It packs down into a racquetball-sized attached stuffsack and has a key hook. It is brilliant.
Here's what I do: I get my groceries in plastic bags, but re-use them as trash bags. Saves money and on balance, I suspect it's the lesser evil from an environmental perspective too: it takes away the impact of manufacture and disposal of a) special-purpose trash bags I'd have to use otherwise, b) their packaging and c) the alternative canvas bags, which let's not forget, also have to be made and disposed of with some regularity as well.
very interesting and using cloth bags are the best way to go. i also agree banning of both in food products. however does any one knowhow much of plastic and paper goes into packaging technology gadgets stuff or making of currencies?
Is it common to recycle plastic bags?
Does every recycling center?
I do not believe mine does in Cincinnati.
I find it easier to carry paper bags onto the bus, or walk home with from the grocery store. And I have resused them before, but if my recycling center takes bags then i may switch.
I like to take my canvas bag but when i am on the run i don't have one on me unless i plan ahead of time so I usually choose paper because I know that i can recycle that in my home.
OK... silly article. I like the facts behind it and most items are interesting things to know. However, the article doesn't answer the question. If you ask which is better, plastic or paper, there are 2 options. Granted, it is best to take a bag that doesn't get thrown away. However, that wasn't the question. Are plastic or paper bags more environmentally clean when the entire equation is looked at? The above still isn't conclusive. A situation should be presented to clarify the question such as, "... you forget your re-usable bag at your girlfriend's house on the way to the grocery. You don't notice until you are checking out. Should you use a plastic to carry your condoms home or use paper?".
The bag issue is only small change.
If you want to make are real difference, you should concentrate on the packaging of the products - this is where the real impact on resources and landfills can be made.
Plastic bags have a much smaller contribution to these problems then packaging does, but it's a lot easier to deal with.
Emily, if you are reusing your plastic bags to clean up after your dogs, aren't you basically recycling them? Win-win if you ask me. I know it's not the same, but at least the bag IS getting used twice before ending up in a landfill.
If they added a sizable tax, all of which could go towards carbon offsets, the habits of people would change quickly.
We could get past this question because if everyone was charged a $1 per bag, paper or plastic, then they would start to keep bags on them the same way they keep their phone, or keys, or make up.
I've been carrying items home from stores for years now, people still give me a bad look. I also have some roll up micro-thin bags that can be easily tucked away in my car or girlfriend's purse.
It's not always easy using a canvas bag, either.
Check out the problems I've had:
http://www.gravyjefferson.com/2008/06/my-kick-ass-grocery-bag-always-gets-me.html
I'm surprised how so many people don't know about new technologies that can really help with the plastic problem of the world. There's this new additive from EPI (http://www.epi-global.com/) where you can simply add into the plastic mixture during production of conventional plastic products (bags, bottles, trays, packaging) that will make it biodegradable.
With the additive, the plastic will biodegrade 60% in 1.5-2 years in the landfill. The biodegrading process is triggered by heat, mechanical stress, moisture, light, bacteria. The additive only adds a few percent to the total production cost. This technology can really be applied to so many things and will change the world on how plastic is used and perceived.
This technology is already being used all around the world.
Looks like this post was inspired by reusablebags.com -- they have been waking people up to these basic facts and concepts in a big way for past 5 yrs. -- always great to see this issue getting attention so people learn to avoid ALL use-and-toss bags - whether paper or plastic
I really doubt that the virgin pulp referenced is from a non-renewable lumber operation and somehow contributing to deforestation. My feeling is that most wood pulp used in kraft paper comes from renewable forestry operations using trees that grow to effective maturity in just 5 to 10 years combined with recovering waste byproducts of less-renewable forestry operations such as bark and scrap from lumber milling operations.
Paper bags can be easily recycled and most paper bags I've gotten at the grocery store quote some percentage of recycled content.
I would wager that if you can point to a case for deforestation it's due to wood used in structural applications such as construction materials and shipping containers. Telephone poles, wooden posts, beams and boards for houses and decks, shipping pallets and so forth.
I just got back from living in Europe for a year, and am now accustomed to bringing my own bags to the grocery store. Almost all stores in northern Europe charge a small fee for each grocery bag used at the store (banning them outright is a bit absurd and unlikely to fly in our economy), roughly 50 euro cents. The bags are more durable and people hold onto them for reuse.
While Trader Joe's offers a rebate for bringing in your own bags, that strategy is less effective in the same way that organ donors are less frequent in the US versus Sweden. What do I mean? It's the opt-in versus opt-out concept. Swedes are automatically enrolled in the organ donor program unless they tick the box saying they do not wish to participate. In the US, however, Americans must opt-in (see The Paradox of Choice for more on the psychology of that).
It's the same thing here. You gotta be on the more persuasive end where money talks: in this case, forcing people to pay a very slight fee instead of rewarding them with something negligible. It'll force better habits instead of encouraging the status quo. Trader Joe's and WF can start doing this, as their customers already have the right mindset, in addition to the stores having very specialized products that are often harder (or in TJ's case, impossible) to find elsewhere. The proceeds can then go to environmental causes, etc. and they can also save on plastic bag costs themselves.
Furthermore, canvas bags aren't the only answer. While those are great for heavy lifting, there are also compact nylon styles (example here) that fold up into a small packet (slightly smaller than a fist) that you can throw into your workbag/purse or store in your car. I always have one of these on hand in my bag just in case I decide to go to a store on the fly. For heavy duty grocery trips, I bring along the big canvas bags as well.
Additionally, recycling seems to have the same effect on consumption that sunblock has on sun overexposure: it lulls the user into thinking he/she is okay in doing what is known to be bad. Just like sunblock is not so effective at stopping skin cancer (as recently disclosed in the news), recycling doesn't wipe the slate clean for garbage production. I have a friend whose household used plastic cups and plates for every meal and threw out 2 big bags of trash a day, just because they didn't want to wash dishes and thought recycling took care of it all.
But thankfully, unlike them, most people just need a slight nudge towards conservation.
Actually, plastic bags will degrade, but really slowly. Thats becouse polimer chains are very long, and microrganisms can "eat" them only from both ends. When polymers contains starch, degradation of starch cause breaking of chains, and in this way bacteries can start degradation process from multiples end, what will lead to faster decomposition.
Completly biodegradable polymers, like mentioned PHA or PLA are as good as the standart ones, but, they are approx. 10x more expensive..
( sorry for my english) :>
What about using paper for garbage bags. In landfills, don't they biodegrate? Does pastic? I use cloth bags most of the time but I will get paper and reuse them for trash!
Great post.
We have been using canvas bags for years now. Once you condition yourself to pack the bags when you shop, forgetting them just doesn't seem to happen anymore.
We do all our shopping at a local farmers market and pretty much everyone uses canvas bags. One thing I've noticed though is that people are still using those clear small plastic bags to put their vegetables in so some alternatives might be needed to combat this.
If you don't believe forrests are being clearcut for paper, go to Washington (state). I stood in the middle of a forrest that was completely cleared on one side of the mountain (10 years ago...). There was tree stumps, and nothing else. When we went down the mountain and went to cross the bay (sorry I was young, I don't remember names) on a ferry, I saw the paper mill... or smelled the paper mill. Don't tell me they don't clearcut for paper or anything else, that's just ignorance and no