How to decipher the recycling numbers on plastic stuff

Written by erik


You know those little numbers inside the recycling symbol on the bottom of plastic bottles and containers? Well, the other day when I read that those numbered with a 7 might contain BPA, and therefore not be suitable for my kids to use, I realized that I hadn’t a clue how to decipher the numbers. Which made me think that perhaps I should learn, and share.

Most plastics in the US are labeled with the numbers 1 through 7, in line with the code developed in 1988 by the Society of the Plastics Industry. The numbers refer to the type of polymer used to produce the plastic in question. You would think, given the use of the recycling “chasing arrows” around the numbers, that the numbers refer directly to the plastics’ use in recycling, but they don’t.

And that is what has confused matters. I wish I could tell you that it’s OK to put only certain numbers into your local blue box recycling program, or that it’s OK to put all kinds in, but the reality is that it differs from municipality to municipality. In general, it seems that a number 1 or a number 2 symbol is the lowest common denominator when it comes to recycling — most every program can handle stuff with those codes.

There’s a full list with a lot of detail here, but in general you can be pretty sure that plastic containers for soda, water, and food are recyclable, as are laundry detergent and shampoo bottles. OK, but what about everything else?

Here in San Francisco, I get the following joyous proclamation from the good folks at SF Recycling — “The days of looking for numbers contained in the recycling symbol on plastic containers are over in San Francisco!” That’s heartening. Now we can just put in everything except plastic bags and other film plastics in the blue box.

I’m afraid that you’ll have to look up your own local recycling service to find out your local rules. Don’t have one? Start one up!

When you are on the road and away from your home rules, you can be pretty sure that 1’s and 2’s are always recyclable (except bags).

And if you are vexed by the question of how clean the plastics need to be, don’t fret too much about it. They don’t have to be dishwasher clean, but it’s best if they are thoroughly rinsed. Most of them end up in applications like plastic lumber, where the blemishes and imperfections brought on by having some foreign matter in the recycling tank don’t matter so much. That said, since most recycling centers still do a lot of separation work by hand, you are doing the workers a real favor by rinsing.

I do have one remaining question. How much of what I drop into the blue box actually gets recycled? I bring it up because the Coop America web site suggests that perhaps ONLY the 1’s and 2’s do:

> While the materials that are technically capable of being recycled don’t vary from place to place, … there are a range of tactics that municipalities use to maximize citizen participation in recycling. For example, some municipalities that do not recycle any plastics #3-7 nonetheless advise citizens to put all plastics #1-7 into their recycling bins, out of the belief that more people will participate if they don’t have too many complicated rules to follow. Then the MRF fishes out whatever they cannot recycle and sends it to a landfill or incinerator.

And reader Jane Martin helpfully provides the scoop on our local recycling program in San Francisco:

> SF sends our #2,4 and 5 plastic to Lodi, CA to a company called Epic Plastics. They produce primarily bender board or plastic lumber.

> The #1,3, 6 are being bailed and shipped to China. China is paying for the material, and they are not burning it, rather they are sorting it and melting it down into plastic pellets that are then remolded into recycled
plastic products much of which is then sold back into the United States. Many times the products are not being labeled as having recycled content.

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  1. mervis

    Question: if plastic bags are marked #2, why can’t they go in the bins with bottles?

  2. Jamie

    The recycling facilities do a lot of work by hand indeed. One thing it’s important to note is that screw-on lids are not always recyclable. Check with your solid waste bureau to see how they handle lids. When I called ours, they indicated that items with lids screwed are discarded as they are too labor intensive to remove.

  3. Jamie

    To the commenter above, I asked our municipality about plastic bags as well. The reply: “Unfortunately all film plastic tangles the sorting machines.” Grocery stores often have venues for recycling the plastic bags if you haven’t switched to reusable ones yet.

  4. dan

    I used to be in the military and we had a mandate to start recycling some paper and aluminum cans. So we had two separate cans for these recyclables. It made you feel good.
    Then, I had an injury and had “light duty” for a week and was stuck with cleaning and empying trash and such. When I got to the recycling cans, I asked where I put those and was told in the dumpster with the other trash. I was floored. I argued a but, but those with much more rank than I had told me to do it and be quiet about it. I did it, but wasn’t quiet about it. It seemed that the only people whe got upset were the low people on the totem pole like me. Those with rank told me that it was just because of the mandate that they even had to put the cans there.
    So often times I wonder what happens if I accidentally put in the wrong plastic, or leave a lit on a bottle or something if the whole batch get’s thrown out or anything.
    Nashville has got to have one of the best recycling programs I’ve ever seen. No separating of anything. I had to get extra bins even, but many people argued against it. Then we moved outside of Nashville and we’re back to separating and looking at the numbers on plastic (where I’m at now only does 1 and 2). I still recycle because green is a part of my life now and I’m passionate about it, but it’s certainly less pleasant than what it was in Nashville (and definitely better than it was in Grand Forks Air Force Base when I was in).

  5. OldDave

    For Dan, the truth says it all.
    Freaking Government. Military just does not care. There are very many cases like that.
    I am tired of my government speaking one way and doing just the other. STOP IT!

  6. Eric

    Surprisingly, San Antonio has the largest and best recycling program in Texas! We get two nice 96-gallon rolling bins from the waste management. One for recycling, one for trash. They pic up each once a week. Plastics 1-7, glass bottles and jars, aluminum and steel cans and paper all go in. Easy breezy! About 60% of what we used to throw away now goes to recycling.

  7. Deborah

    Actually, many food items are packaged in plastic that has #5, which is very unhealthy (the bottom of the ketchup bottles at my local food co-op–horrors!). Those large pale blue bottles used for storing water?? Bad news—unhealthy plastic. Supposedly, #1 and #2 are safe for humans, but personally, I’m systematically getting rid of all plastic in my home and storing food in glass jars. I now use a stainless steel water bottle–healthier for me and no toxic waste for the environment in our landfills. So be sure to check the numbers before assuming that the plastic you’re using is safe 🙂

  8. Cheryl

    Is only #1 & 2 plastic safe? Does the plastic get more harmful as the number goes up? If not, does anyone know specificly what the numbers mean?

  9. Erik (TerraPass)

    Hi Cheryl – The numbers refer to the type of polymers involved in the manufacture of the plastics. They don’t shed any light in terms of safety. Does anyone out there know of a good guide to plastic safety? I’ll look for one myself. For now I’m happy to have figured out which ones are most likely to be recyclable.

  10. P Stover

    Thanks for the info and the great link. I’ll use this with my middle school students. They don’t have a clue why we recycle or what to put in the bin.

  11. Adrian

    I’m married to a recycling professional, so here are some bits I’ve picked up
    In response to #1, bags are film plastic, which is subtly different from the bulk plastic used in containers. Same material, different properties. Like different flavors of ice cream.
    Noting #4 and #6 suggesting that putting “all recycling in one bin” is better (known as single stream in the industry), it actually means that *more* gets thrown away, and what does get recycled is at a lower quality. Paper contamination is the big driver here. This is actually a big factor in driving US paper mills out of business as they can’t handle the lower quality fiber. Without being able to get clean fiber, they cannot compete with cheaper overseas stuff. In addition, it only saves the trash hauler money. The municipality (or other generator) will generally get less from single stream recyclables, and when commodity markets go down (like they are now), it gets harder to sell any of it, and therefore more goes into the trash.
    Replying to #7, I just have to point out that there is a *lot* more energy that goes into mining, refining, and fabricating the stainless steel bottle, so the energy (and therefore carbon) footprint is larger, probably by a factor of at least 1000. Not denying that it’s healthier though.
    In general, plastics (and other recyclables) are a commodity market just like any other. You have to compete on cost and quality. When recycled materials are cheaper or command enough of a premium to justify purchasing them, they’ll be recycled. Otherwise they’ll be thrown away.

  12. Anna

    In our town, Scottsdale, Arizona, they have a contract with a paper company to handle much of our recycling. So from the beginning of curb side pickup we’ve been able to include all paper, colored, with windows, light cardboard, etc. But they are fussier about plastic. They request that we do not select by number, but by shape of the container. Cottage cheese containers, no; screw top bottles, or containers with a neck smaller than base, yes. when I asked about this I was told that a significant number of manufacturers put erroneous recycling numbers on plastic containers. And this is enough of a problem for the buyers of recycled material that they won’t buy a batch of 1’s and 2’s. Somehow the shape of the container is a more reliable predictor of its contents than the stamped number. It seems to me that better enforcement is the right answer.

  13. Sarah

    I live in central PA and the recycling program here (and in other rural areas I have lived) is absolutely terrible. There is no pick-up: one morning a week (Saturday) the recycling center is open for your recyclables to be dropped off. Only 1 and 2 plastics are taken, plus aluminum and metal cans and paper…but most plastic tubs are 5 or higher, so lots of plastic and styrofoam still go in the trash. As a result of the effort that it requires to recycle, lots of people don’t do it at all, and still throw away plastic bottles. It is so frustrating.

  14. Rob

    Here in Burien (Seattle) The rule is Bottles 1 and 2 Yes, sheet plastic no- The bags go to safeway for recycling- better yet- Why not carry a canvas bag and then you don’t have to worry about recycling plastic bags!

  15. Adrian

    One note is that there is a significant component of weight to what can be economically recycled. Styrofoam is a good example of “no matter how much you can collect, you can’t get enough money to haul it anywhere.” It doesn’t compress well and it’s very light (why it’s used as packing material), so there is no way to economically reuse Styrofoam. Bags and bottles are different, but nothing beats metal. Infinitely recyclable, and you’re saving a ton of energy and other negative externalities by not mining more of it… Plastics I think will eventually break down to a low enough grade that they’ll have to be reformed.

  16. Rachel

    Getting rid of those damn plastic bags —-
    When my less-than-environmentally-conscious friends end up with a lot of those grocery bags, I collect them, flatten and fold them (while I watch TV, so I’m multi-tasking) and take them with me to the Farmer’s Market and give them to my vendors to re-use. At least they’re getting at least one more go-round! (and, FYI, I carry a multitude of re-usable cloth bags in my car, and for Christmas last year, I bought the ones the local grocery stores were selling and put everyone’s presents in them, instead of using wrapping paper; they’re about a dollar. Maybe a few of my friends are actually using them, but I think the bag should include a hanger tag for the door knob that says “GET YOUR BAG and PUT it back IN THE CAR!!”)

  17. jane martin

    i’m in SF so asked at the department of the environment. here’s the response:
    SF sends our #2,4 and 5 plastic to Lodi, CA to a company called Epic Plastics. They produce primarily bender board or plastic lumber.
    The #1,3, 6 are being bailed and shipped to China. China is paying for the material, and they are not burning it, rather they are sorting it and melting it down into plastic pellets that are then remolded into recycled plastic products much of which is then sold back into the United States.
    Many times the products are not being labeled as having recycled content.

  18. Nathan Potter

    Hi Erik – just a short note of thanks for referencing the plastics recycling codes list on our website. We hope that it’s helpful to the readers of this article.
    Being in the plastics industry, the buzz about green plastics is reeling, which is a good thing! Many resin manufacturers are actively working to develop plastic materials that are biodegradable, include recycled content, or are derived from renewable resources.
    Recently we developed a Green Plastics search tool to help design engineers select more eco-friendly materials to use in the products they create.
    Here are two more resources that might be helpful:
    Find a Recycling Location
    Which Plastics Are Safe?

  19. Matthew

    Wow, I never really thought that these numbers meant anything meaningful for my use. I’ll have to keep this in mind on all sorts of plastics!