By Lori Brown on Mar 2, 2009

The Pizza Box Mystery

Many people assume that pizza boxes are recyclable. In fact, most boxes have recycling symbols on them and are traditionally made from corrugated cardboard. They are, in and of themselves, recyclable.

However, what makes parts of them non-recyclable is the hot, tasty treat that comes inside them, specifically, the grease and cheese from pizza that soil the cardboard.

So there you have it, pizza boxes that are tarnished with food, or any paper product that is stained with grease or food, are not recyclable – unless you remove the tainted portions.

But why is this? And what are the implications for the general, pizza-loving public? Mmm, pizza.

Find a Cardboard Recycling Solution Near You

Andiamo a mangiare...and recycle too! Photo: Recyclingweek.planetark.org

Andiamo a mangiare...and recycle too! Photo: Recyclingweek.planetark.org

How it Gets Recycled

Food is one of the worst contaminants in the paper recycling process. Grease and oil are not as big of a problem for plastic, metal and glass, as those materials are recycled using a heat process. But when paper products, like cardboard, are recycled, they are mixed with water and turned into a slurry. Since we all know water and oil don’t mix, the issue is clear.

Grease from pizza boxes causes oil to form at the top of the slurry, and paper fibers cannot separate from oils during the pulping process. Essentially, this contaminant causes the entire batch to be ruined. This is the reason that other food related items are non-recyclable (used paper plates, used napkins, used paper towels, etc).

“The oil gets in when you’re doing your process of making paper,” said Terry Gellenbeck, a solid waste administrative analyst for the City of Phoenix. “The oil causes great problems for the quality of the paper, especially the binding of the fibers. It puts in contaminants, so when they do squeeze the water out, it has spots and holes.”

But what about other things regularly found on paper products, like ink? “Most inks are not petroleum-based so they break down fast. Food is a big problem,” he said.

Also, be mindful of adhesives that may be on the pizza box (coupons, stickers, etc.) as those are contaminants. Known as “pressure sensitive adhesives (PSAs)” these can ruin the recycling process just as much as oil or food remains.

An Interesting Development: This City Found a Way to Recycle Pizza Boxes

Sneaks

Many people admit trying to “sneak” their pizza boxes in with cardboard boxes and such. In reality, this does more harm than good as the contaminated cardboard could ruin the whole recycling batch.

In fact, contamination in the recycling business is a big problem. Some estimates put the costs of irresponsible contamination in the neighborhood of $700 million per year industry-wide. Gellenbeck estimates that for the City of Phoenix, contamination costs them around $1 million annually, because of damage to machinery, disposal costs for the non-recyclable material and wasted time, materials and efficiency. With the City processing 129,000 tons of materials in 2008 (around 7 percent of this is cardboard), money is an important factor as to why residents should know what their municipalities do and do not accept.

A New Hope: Will This Reusable Pizza Box Catch On?

So, What Do I Do?

The easiest remedy for this problem is to cut or tear out the soiled portions of your pizza boxes and trash them. For example, you can tear the top of the box off, recycle that and throw away the bottom part containing the grease. If the entire box is grease-free, the whole box can be recycled with a guilt-free conscience.

Another option to recycling cardboard is to compost it, although the grease rule still applies here as well. “Even with oils, you shouldn’t compost [greased cardboard]. It causes rotting, you get more bugs and smell and it’s just not good for the plants,” said Gellenbeck.

Most importantly, being well-versed on what your local recyclers accept, can make the biggest difference. “It all depends on where your processor sends your paper, too,” said Gellenbeck, whose authority applies only to the City of Phoenix. “If you can keep a particular thing like the food out, the plastics out, all those things that really shouldn’t be there, it would help.”

Answer More Tough Questions: 10 Recycling Mysteries, Solved!

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Comments

  1. colleen r dawson says

    I have a audiovox cell phone, when i purchased it ,no one told me it was used, i cant see the numbers the lights dont work and there is no color, i tried to exchange it or have it refurbished, now i am told the phone is absolete, and need to get a new one, is there anyone ,company out there that could fix my cell, i really like, it, or is it just a waste of time and money, should i just get a new one, colleen please answer
    dawsoncolleen@yahoo.com

  2. Bob says

    I thought this artice was great because I have been throwing my pizza boxes away in the recyling trash can for many years, but now I will be able to stop.. Thank you EARTH911

  3. says

    Wow, this is an interesting fact. I knew that the pizza boxes were recyclable but didn’t know about the exception that if any food gets stuck in the box it does not get recycled at all.

  4. Dust from PAGE says

    The post is so true in my area I am trying to get the small pizza places to put a piece of wax paper or other insulator in so that the cardboard can be recycled. I know one they started using another piece of thin cardboard like a tray so that customers can take the pizza out and put it on the table. These things can prevent tainted cardboard.

  5. Cathy says

    I’ve been laying the boxes face down on my garden paths. Originally I thought grass paths between my raised beds were pretty. But turns out to be very difficult upkeep. The boxes work well. I figure over time I’ll be able to dig out some great soil to add to the beds. (It is a little shocking how quickly I’m getting all the paths covered!)

  6. Tony says

    Here in Morgan Hill, we encourage our residents to place pizza boxes and other food-soiled paper products in with their yard trimmings for curbside collection. It’s a process that works great and really cuts down on the volume of trash….especially for families with lots of teenagers. People living in other communities should let their recycling company know that they’d like this service added.

  7. Bobby says

    We visit our local pizzeria at least once per week and the first dozen or so times the owner and workers looked at me kind of strange as I kept bringing back my “gently used” pizza box. We have been reusing our box for a number of years, and our goal is to use no more than 3 boxes during a 12 month period. In 2008, we cut that down to 2 boxes – of course the folks at the pizzeria are now enjoying the fun as well – we kept track and last year we had 41 pizzas! We had a little ceremony in early January when it was time to get a new box and start keeping track again. The key of course is that the pizza maker is “gentle” on the box and we clean it as soon as we get home and take the pizza out. If after all it’s use we can keep it clean, we do then recycle it with our cardboard.

  8. Jessica says

    In response to a comment above, pizza boxes are usually not allowed to be picked up with yard trimmings and green waste. If you live in San Francisco and your waste hauler collects compost, then yes you can mix your pizza box with your green waste. If your city does not collect compost, I doubt they will collect your pizza boxes with the yard trimmings. But as the comment stated, check with your waste hauler.

    And thank you for posting this, I work in waste diversion and contamination is always an issue. Education is the one of the answers.

  9. Joe says

    Te truth is the disposable nature of the whole “call the pizza guy” process is what is flawed. I know most people don’t like to hear things like this, but the best solution is don’t buy the pizza in the first place. Think of the gas it takes to deliver just one meal. It’s more than what to do with the box. Walk to the restaurant and eat it there, or better yet, make you own.

  10. Laura lee says

    I like the idea of reusing your pizza boxes, like Bobby & family are doing. We live in a totaly dispossable world, I have adult kids and there out look is oh well i can go out and buy another, instead of being conciences of there surroundings

  11. Brad says

    I also like what “Dust from PAGE” says. I think some kind of insulator between the box and the pizza would be a good thing, but it would have to be either biodegradable or recyclable. The cardboard insert would be one option, but perhaps another option would be a (recyclable/durable) plastic insert that can be cleaned and returned to the pizza joint (for a pizza discount perhaps) or at the very least recycled. Trouble is, some people who are not up on their recycling might just throw it away with the box and this would add to the problem…

  12. Tania Levy says

    City of Berkeley recycling program: good comment about effect of food contamination on recycling paper. But “stickies” are not a problem. The paper mills added technology many years ago to remove self-adhesive labels, tape, cellophane windows etc. as they assume these materials will be present. Otherwise, they could not accept post-consumer paper.

  13. Rick says

    This is not a consumer problem. It is a complaint by the recycling industry to avoid having to pay for an additional process to clean up what they bought or took for free. Consumers pay a hefty price for containers, advertising and seller’s profits in the total product cost and deserve safe, healthy food without accepting additional costs and burdens for container disposal. Why disposal costs are not part of a manufacturer’s responsibility, who design these containers, etc., is based on faulty property ownership laws and is nothing more than a sham. We buy the useable consumable product not the manufacturer’s distribution tool. This seems to me to be the recycling industry’s version of their “faith-based initiatives for profit.”

  14. says

    wow… -I had no idea the seriousness of this. I just assumed that a process that dissolved the food-grease (like benzene, as~used in the dry-cleaning business) might be used. I guess that this would contaminate the paper pulp too.

    Great!

    -Joel

  15. Jenn says

    Another option is a “Take and Bake” pizza place like Papa Murphy’s. They usually put the pizza on a thin piece of cardboard or thick wax paper that goes in the oven. And they just wrap it in cellophane instead of putting in a box. Or like someone else said make your pizza. It’s healthier too!

  16. Patti says

    Very useful information! I certainly understand why pizza boxes should not be recycled due to the grease contaminant. The article also mentions paper plates, towels, and napkins. I often toss those items in for recycling if they don’t have grease stains or if they were used only for drying my hands after washing them with soap and water. So is this acceptable, or should they not be recycled at all??

  17. Michelle says

    This is a great article! I’m trying to plan a project for our grade school for earth day (all of april). Each week will be something different to raise awareness or a service project. I think this will work great!
    Thanks! Michelle

  18. Solver says

    If everyone who reads this board would simply barf up the pizza you eat, and recycle that, we could probably get rid of at least one landfill within a week. Within a month, the loss of that many needless airbreathers would allow us to close many more. Good grief, you people are so concerned about waste! What about time wasted? The amount you spend trying to feel better about yourselves while getting constipated staring at your big blue bin could be put to better use saving the economy! If so much of your stuff is getting recycled anyway, why does the damn recycled stuff still cost too much? I wonder how much problem all of our dirty diapers are causing in the recycled paper? Cut the damn trees down – they’ll grow back faster than you all will get back to useful work.

  19. bill says

    If the food and grease from the pizza are not recyclable. Then imagine consuming that in to your body. I love pizza as much as the next, but never knew the bi-product from it could damage or ruin an whole batch of recyclable cardboard.

  20. says

    Great article! I wanted to inform everyone of an emerging alternative to the pizza box that is not mentioned. I am a partner in Flat Pak Packaging, Inc and we offer the patented Flat Pak Pizza System that consists of a plastic bag and tray. It is a truly green solution to the pizza box as the bag is 100% recyclable with biodegradable componets and the tray is 100% compostable, made entirely from plant fibers so that NO TREES are used in its construction whatsoever! Pizza Hut reconfigured pizza boxes to save 275,000 trees a year in 1992. Imagine if we could eliminate corrugated from pizza COMPETELY how many trees we could save! Pricewise, the Flat Pak Pizza System is typically CHEAPER than the corrugated pizza box. Our website is currently being updated, but please visit when you have the chance. Feel free to e-mail me with any questions you may have. Thanks!!

  21. Holly says

    Thanks Lori! I love it any day that I learn something new and I, also, have stood at the recycler wondering yea or neigh…and then figured the food tainted it. I HAVE cut the bad part out and put the rest of the box into the bin, so now I feel good about that! I will begin to remove the pizza when it comes home and before it gets soiled with grease.

  22. says

    i generally inspect used pizza boxes prior to throwing them into my recycling and make a call. if they are not that bad, i put them outside face up to get rained on an cleaned. usually, that takes care of the problem, as far as i can tell.

    but regarding the cost of recycling, i have been under the presumption, based on various studies in the past, that most recycling doesn’t work very well anyway. from what i understand, ONLY aluminum is worth recycling via the current process and most all other forms (glass, paper, plastic) operate in the negative cost, and the processes used are actually bad for the environment (sort of like “green cars” having expensive batteries which need to be replaced every few years and are bad for the environment). ALSO, that much of the recycled material actually just winds up in the land fills.

    i’ve just been going along with it for years living in a house with 9 people, but feeling like i’m not really helping in doing so, and merely just “following the law”. is this still true, or is there some new and improved recycling method that actually works well? i would not be surprised in the least, for nearly everything the government becomes involved in doesn’t work! 8-)

  23. B Raymond says

    In our part of Washington State, our yard waste collection company–Waste Management, Inc.–happily accepts food waste in with the yard waste. All of that is taken (a short distance) to a private composting facility. This includes soiled pizza boxes and and food soiled paper.

  24. Pam K. says

    A SMALL amount of grease or cooked food residue shouldn’t be a problem if you are making your own compost (assuming there is enough “clean” compost to mix with). Extrapolating on the garden path idea–another use for the “dirty” part of the pizza box (or other cardboard) is as a weed barrier when creating raised beds or underneath decorative mulch. It will decompose eventually and add to the soil. If at the bottom of a raised bed it will discourage weed seeds from sprouting but allow roots from plantings to penetrate to the soil below.
    By the way–I love the idea of reuseing “gently used” pizza boxes for those who eat takeout pizza regularly–not the solution for everyone but still….cool!

  25. Gabe says

    I am actually quite upset. I’m glad that I finally learned this, as I can’t count the number of times that I’ve recycled greased pizza boxes. I think instead of calling it “irresponsible recycling” perhaps it should be “not raising awareness.” I’m astounded that I haven’t learned this before, and I think it’s because of poor education on the matter, which should be corrected. If it really wastes $700 million per year, I think the best remedy to the problem is actually let the public know, not sit back and eat the deficits.

  26. says

    Wonderful article and a lot of great followup comments! I think many hit the nail on the head by saying this is an “awareness issue” or “lack of education”. Being a doctor that tries to be ecoconscious at my office, using “green” energy, etc., I was surprised to learn that the occasional pizza box (guilty pleasure) that we had been “recycling” was actually harming the process. Not that I’m the smartest tack in the box, but if a doctor doesn’t know @ this, how is the average American consumer going to know or even care? I think if we use this positive knowledge and spend the energy to spread awareness within our families, friends, offices, neighborhoods, we might be able to make a difference in a larger way.
    However, I also agree with some of the above people (perhaps Lori could revisit the original article and sum up the best of the above comments?):
    1. REDUCE: eat at the restaurant; don’t take out/have delivered; make yourself; avoid unhealthy food in the first place!
    2. REUSE: recyclable plastic pizza boxes; use paper/plastic grease barriers; wash your boxes (sorry, but, blech!); increase composting programs in cities
    3. RECYCLE: perhaps this _should_ be something the paper recycling manufacturers should worry about, not the consumers? since the average consumer is bearing the cost of the box & is apparently not knowledgeable in the first place about recycling in general?

  27. Lori Brown says

    Hi DrT_WholeChiro,
    Your suggestion to revisit the original article and sum up some of the above comments is a great one! We’ll look into an update of this article in the future. Thank you.
    Lori Brown
    Earth911

  28. Mickie says

    In Seattle and the Burbs, pizza boxes are composted, along with paper towels and paper napkins. They go into the yard waste bin, which is picked up once a week and then taken to a composting facility.

  29. Chris says

    Reusing the box is a great idea. I do this whenever I get a beverage carrier from a fast food place. The thought of throwing it out or even recycling it when it is perfectly fine bugs me. A note about the pizza boxes: check your local Board of Health regulations. In my state, you cannot bring back a used pizza box as it is supposedly a health hazard. You’re not supposed to be able to reuse a paper bag, etc. It’s crazy but that’s our state.

  30. BReeve says

    I contacted Papa John’s about clarifying the recycling symbols & “Corrugated Recycles” stamps on their pizza boxes and forwarded them this article. Has anyone else contacted any pizza places??
    “Fight the good fight & interrupt the main stream, even a dead fish can just ‘go with the flow’.”

  31. Tony says

    Hi Lori,
    my name is Tony and i am the owner of a pizzeria located in the heart of a college town. Needless to say about 90% of my costumers are college students, over the years i got used to a lot of their irresponsible behavior but some of them i just can’t get used to, here’s what happens, when they order slices or a whole pizza we ask them “for here or to go?” they say to go and after we put it in the to go pizza box they walk a few feet sit down and eat it at the table. Needless to say the box gets grease all over it and it becomes non reusable and non recyclable. That is so not necessary and wasteful considering that it happens 8 out of 10 times. A lot of times i still give it to them to stay even if they tell me to go, but they won’t take it until i put it in a box. It is so frustrating, especially when you think that they are college students and they should know better. Do you have any suggestions on how to solve the problem?

  32. says

    Great article. I didn’t know that, thanks! (I’m going to have to share w/my roommates; we always eat pizza!)

    Hi Tony,

    I was just reading your post, and I think I know why they’re doing doing that. Sometimes when I eat out, if I don’t know how much time I have to eat my food, or if I will have left-overs when I’m finished, I just ask for it “to-go” so that I have the option to take it with me. (If I do end up eating it all, I throw the container away when I’m done.) What you might try doing is offering (or having available on the side) a “to-go” box, for the left-overs. That way if they do eat nearby, and if they have to leave, or they have left-overs, the can just conveniently grab the box/container and be on their way. Having this convenience might make them more willing to have it served “for here” since it’s easy to switch over. If they do finish eating all the pizza in-house, and don’t grab a box, no harm done. If they do grab a box, and don’t use it, at least it’s still clean and recyclable.

    Just a thought, even though I don’t know anything owning about a pizzeria, lol.

    Hope that helps :)

  33. elaine says

    Wouldn’t it be a simple ‘fix’ to require all pizza companies to put a removable lining in each pizza box that wouldn’t transfer the grease to the cardboard in the first place? That would allow the whole entire box to be recycled! Also, require removable labels, etc. to be made of recycleable paper, and easy to remove from the box, so whether they are used or not, they would not hinder the recycling process! I’m sure that the pizza-box manufacturers could figure something out! This seems like a huge problem that could be remedied by some sort of a fairly simple fix! People who can deal with such things: Get your brains in gear, and DO SOMETHING ABOUT THIS !!!

  34. says

    Lori, thanks for a great article, though my wife won the bet on not being able to recycle the pizza box in which we just consumed the contents. I like the thought on some sort of a top/bottom liner for the pizza box…something biodegradable in a few years. Again, well written and informative.

  35. Joanna says

    Our local pizzeria doesn’t use a cardboard box to put pizza in. They use a paper bag with a small round plastic table in the center of the pizza so they can stack the pizza’s. While the bag would still be greesy and not recyclable, it would be less waste than an entire cardboard box.

  36. Brian says

    Seems to be an easy fix. Require all companies that use pizza boxes to put a plastic liner in the box that prevents oil from leaking into the cardboard. Design the liner so that can withstand the delivery process, but is easy to remove for recycling. I would imagine, once washed, both the plastic liner and the pizza box could then be recycled.

    Voila.

  37. Keith says

    The easiest fix I have come up with is to just shred mine in my shredder and add it to the compost pile. That avoids the whole problem and the food left on it (once it dries) shreds just fine and actually helps the compost. This would even work if you have one of the smaller kitchen composters I would think.

  38. Raz says

    Simple solution: Levy taxes on the pizza cardboard suppliers, they in turn increase rates on pizza companies, who will pass on the increase to the customer as a surcharge -> voila….less pizza is consumed, less ‘non-recyclable’ pizza boxes to worry about.

    Find a ‘greener’ route to a heart attack.

    Raz

  39. James says

    When my wife first told me that you can’t recycle Pizza boxes, I didn’t believe her. Guess she was right, and now I know why.
    Great article, thanks!

  40. Nicolas says

    Isn’t it not worth the energy to recycle anything anything but metals? To recycle things like cardboard requires a large amount of energy usually derived from burning fossil fuels. It’s better to let these things just biodegrade.

  41. Bob says

    The stupidity of the recycling game is that it is generally assumed that the only path is to recycle that which has already been made. That the products that are already in production *have* to be left in production and recycling added to the system later down the line. This is soooooooo fcking stupid.

    Common sense tells us that the fix is not to keep making tons of crap and then trying to recycle it, but instead to (1) stop making tons of crap and (2) stop assuming that recycling is an additive measure to reduce the already manufactured tons of crap (which then get “recycled” into more crap).

    So, the only long term answers to the eternal question of dealing with recycling are:

    1. Stop making tons of crap.
    2. Manufacture the crap that does warrant manufacturing using materials that are renewable and capable of being separated and recycled.

  42. says

    Great informative post. I’ll have to pass it along to my cube mate who thinks it’s a good idea to keep all of his used personal sized pizza boxes at his desk because he’s “going to recycle them”. I’ll let him know the dream is over, thanks!

  43. Speaker-to-Animals says

    Pizza boxes may not be recyclable, but they *are* compostable. The waste management program has “green” collection of compostables which include any soiled paper. It’s a far better alternative than landfill.

  44. Endame says

    Maybe someone should write this on the recyclables containers because I’ve never heard such a thing and have certainly thrown away the occasional pizza box in the recyclables can from time to time.

  45. Necromas says

    Recycling just doesn’t seem efficient yet for paper products, partly because of shit like this, and partly just because of all the other costs involved. IIRC without the government funding it is still more expensive and lower quality to make recycled paper products than fresh ones. And paper is a renewable resource that bio-degrades practically instantly. It just seems silly that we’re losing money (the most important resource) just because of some notion that recycling is inherently the better option.

    Ultimately it’s not about saving trees, it’s about saving resources, and until recycled products can be cheaper than the originals (which would be the case if there was a problem getting more wood to use), there’s no economic reason to do it.

  46. says

    Hello Lori:

    I work for ABS Materials Inc (www.absmaterials.com). We make a material called Osorb, which could very easily clean the oils out of pizza boxes and other food contaminated items. Using Osorb to clean the contaminated batches could save all people involved a lot of time and money. If you are interested in learning more about what we do, feel free to contact me.

    Best,
    Jane

  47. Mike says

    WAIT!
    Check with your local recycler before you start throwing pizza boxes in the trash!
    In Monroe County, NY, pizza boxes ARE accepted for recycling (and have been for a few years):
    http://www.monroecounty.gov/des-residentialrecycling.php
    I’m not saying the information about soiled cardboard is untrue. Monroe County may have a separate process to recycle them; they may compost them; or, they may have found a company that has another use for them. Either way, there’s a reason they’re not being sent straight to a landfill.

  48. Julie says

    Organics for compost is becoming much more widespread, and the pizza boxes and wax paper are both accepted in commercial compost programs–not backyard systems. Contact your community and start to inquire about organics collection–eventually with enough calls they will get a system going . . . our community has!

  49. Howard says

    I also would like to add that grease from hamburger wrappers (some fast food places like Five Guys use a paper wrapper rather than a box) makes the paper non-recyclable. The government should immediately institute an oversight process whereby separate receptacle containers are located at every fast-food restaurant in the nation. In this manner, customers can throw their grease-contaminant waste in one, and regular non-grease waste in the other. This will enable us to recycle correctly and to help to save the whales, and the polar bear, and the planet. Fast food establishments found in violation of the grease-separation law should not be allowed to apply for Obama-care waivers.

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