What Do All Those Recycling Symbols Mean Anyway?

Most of us are familiar with the little green recycling symbols that appear on so many products these days, but how many of us actually understand what the codes that go with them mean? HDPE, PETE, LDPE? I sure didn’t when I started collecting trash last year and so I decided to do a little investigating. I’m going to hit the highlights here, but there are a ton of good sources of info out there like the one at The Daily Green. Also, if you are trying to figure out where to recycle ANYTHING at all near you, check out Earth 911. 


Number 1 Plastics: PET or PETE (polyethelene terephthalate)

PETE is most commonly found in soda and water bottles but is used to make peanut butter jars and veggie oil containers as well. It is usually downcycled to make items like polar fleece, tote bags, fibers and carpet. Most beverage bottles are made of this stuff as it is inexpensive and lightweight, but shockingly the recycle rates are only at around 20percent.

Number 2 Plastics: HDPE (high density polyethylene)

This stuff is a bit heavier and is most commonly found in milk jugs, household cleaner bottles, shampoo bottles, some garbage bags, and cereal box liners. HDPE is generally recycled into laundry detergent bottles, plastic lumber, pens, and floor tiles to name a few.

Number 3 Plastics: PVC (polyvinyl chloride)
PVC is found in clear food packaging, some window cleaner and detergent bottles, and the outer jacketing of electrical cables (think ethernet). It’s not as readily recycled and is pretty nasty stuff as its manufacture and burning releases toxins into the atmosphere. When it is taken for recycling, it can be turned into mudflaps, cables, speed bumps and floor mats. PVC can contain a softener (di-2-ethylhexyl phthalate (DEHP)) which has been shown to be an endocrine disruptor and human carcinogen – so you may want to avoid it altogether. Good times!

Number 4 Plastics: LDPE (low density polyethylene)

This is the stuff we probably see the most of, after PETE in water bottles, as it’s what goes into those plastic shopping bags. Other uses are squeezy dispenser bottles, bread and frozen food bags, and some clothing and furniture. LDPE is becoming easier to turn in for recycling and can be used to make trash can liners, shipping containers, composters and envelopes.

Number 5 Plastics: PP (polypropylene)
You’ll see PP 5 in bottle caps, plastic drinking straws, some plastic food containers and medicine bottles. Polypropylene is one of the more commonly accepted plastics for recycling and can become signal lights, brooms and brushes, ice scrapers, and landscaping borders. Because it has a high melting point, it is commonly used in things that will come into contact with heat.

Number 6 Plastics: PS (polystyrene)

Another commonly found one, PS is used in carry out containers, compact disc cases, egg cartons, and “disposable” cups and plates. It is fairly hard to recycle this stuff (many areas do not accept it) and has been proven to leach carcinogenic toxins in many instances. Polystyrene is most commonly found in Styrofoam (they inject it with air to make it light and give it that texture) and can be turned into insulation, light plate switches, foam packing, egg cartons and carry out containers.

Number 7 Plastics: Everything else
Ok, this is a weird one. In an attempt to label everything, they came up with number 7 for things that don’t fit in 1-6. Some of the products that carry a 7 are 5 gallon water jugs, bulletproof material (hopefully you won’t need to recycle this stuff), computer cases, dvds, and a whole host of other things. A lot of local recycling programs won’t take number 7 for the obvious reason that they don’t immediately know what’s what. This is a bummer because as of right now, many compostable products carry a number 7 on them and are therefore getting tossed. Crazy but it’s true. It should also be noted that Polycarbonate which carries a number 7 and is used in many baby bottles and reusable sports bottles (think Nalgene), as well as those office water jugs, can contain the hormone disruptor bisphenol-A which has been shown to leach out due to age or heating over the long term. Ain’t science fun?

So there you have it. This is only meant as an overview but I think it’s worth noting that many of the plastics listed above are not truly recycled (turned back into what they were originally intended for) but instead downcycled (turned into other stuff). As a result, while the plastic is getting a longer life, eventually it’s still going to end up in that landfill and they’re just going to have to keep on starting the chain over from the top every time. All of this requires a tremendous amount of energy, creates a tremendous amount of waste, and adds a ton of pollutants to the planet. So while we all need to Reduce, Reuse, and Recycle, it seems like we should add Refuse to the head of that list and not use these products to begin with.

Food for thought.

Dave Chameides is a filmmaker and environmental educator.  His website and newsletter are designed to inspire thought and dialogue on environmental solutions and revolve around the idea that no one can do everything, but everyone can do something.  “Give people the facts, and they’ll choose to do the right thing.”


William C
William Cabout a month ago


W. C
W. Cabout a month ago

Thank you for the information.

Wills J.
Wills J.6 years ago

I am really appreciate with your great articles. Your thought was really appreciable. Hats off for your awesome article.

Daniel M.
Past Member 7 years ago

The basic building block of plastics is cellulose taken from petroleum, but toxic petrochemical compositions are not the only way to derive plastics. Plastics can be derived from plant cellulose, and since hemp is the greatest cellulose producer on Earth (hemp hurds can be 85% cellA recent technological advance with biodegradable plastics made from cornstarch has led to a new material based on hemp. Hemp Plastics (Australia) have sourced partners who have been able to produce a new 100% biodegradable material made entirely from hemp and corn. This new material has unique strength and technical qualities which have yet to be seen before, and this new material can be injection or blow-molded into virtually any shape using existing moulds, including cosmetic containers, Frisbee golf discs, etc.ulose), it only makes sense to make other organics, instead of letting our dumps fill up with refuse.
The possibilities are endless with hemp plastics and resins, and bio-composites. Virtually any shape and purpose can be fulfilled by bio-composite plastics. Hemp plastics are already on the rise, it is only a matter of time before we will see the need to grow hemp in the United States to meet our demands.

Linda M.
Linda M7 years ago

thanks for posting this

Linda M.
Linda M7 years ago

so glad i found this link today through another post (How to Recycle Everything.)

Heather B.
Past Member 8 years ago

Thanks for a terrific article, Dave!

Amber M.
Past Member 8 years ago

I think it is worth noting here that the number only indicates what polymer the plastic is. Keep in mind, nylon is a polymer as well. The reason why plastics are made of different polymers depends on the use. Like above, using a polymer that isn't heat resistent in something that will go in the microwave wouldn't be a good idea. The number doesn't have anything to do with how easily recycliable a plastic is nor how it is recyled. The basic process is the same, although there are a few differences.

Adam R.
Past Member 8 years ago

Good list! Something that should be printed, no doubt! But you can also use metal waterbottles. They don't solve everything but they've taken out a shit load of guess work from my life, that's for damn sure!

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Holly F.
Holly F.8 years ago

Thanks for that useful post and you're right about adding "refuse" to the mix. - Holly Fisher www.greenofficeprojects.org/blog