The Resin Identification Code (or “chasing arrows triangle”)

One of the confusing things about plastic is that there are so many different types: PET, PS, LDPE, BYOB (OK, maybe not that last one). And the types of plastic you can recycle vary enormously depending on where you live. Plenty of products now have the on-pack recycling labels, but not everything does. Wouldn’t it be handy if you could look at a product and instantly know what kind of plastic it’s made from?

Well, you’re in luck. If you’ve ever peered at the bottom of a plastic bottle, you’ve probably noticed the “chasing arrows triangle” – three arrows in the shape of a triangle with a number in the centre. Many people wrongly think this symbol means the product has been recycled. In actual fact, it’s the Resin Identification Code, used by manufacturers and recyclers to more easily identify the kind of plastic they’re dealing with.

To help you make a more informed choice about what you buy, we’ve created a quick cheat sheet (see table below). And if you’d like to learn a little more, read on to discover some of the key features of each kind of plastic.

 

Symbol

Plastic

Stands for…

Products made from it

Kerbside recycling?*

1

PET

Polyethylene terephthalate

Clear drinks bottles, fruit punnets, textiles

Yes

2

HDPE

High-density polyethylene

Milk cartons, shampoo bottles, cleaning product bottles

Yes

3

PVC

Polyvinyl chloride

Window frames, drainage pipes, clothing, toys, cling film

No

4

LDPE

Low-density polyethylene

Carrier bags, beer six-pack rings, paper coffee cup liners

No

5

PP

Polypropylene

Soup pots, margarine tubs, bottle tops

No

6

PS

Polystyrene

Takeaway cups, “peanut” postal packaging

No

7

OTHER

Other plastics

Acrylic, nylon, fibreglass, polycarbonate, and products made from a mix of materials

No

*We’ve tried to indicate the most common policies, but they vary enormously depending on where you live. Please visit your local council’s website to double check what you can actually recycle in your area.

 

PET symbol

A PET symbol, barely visible on the right-hand side on the base of this shower gel bottle

1: PET

It’s one of the most common plastics you’ll come across, as well as being one of the most widely recycled plastics. But if recycling companies want to produce good quality recycled PET, they need to ensure there’s no contamination, which can mean using some nasty detergents to clean the old bottles we put in the recycling. PET plastic gets turned into things like polyester for carpets and clothing, as well as new PET products if the quality is good enough.

Although it’s fairly easy to recycle PET, it’s also quite easy to avoid it through simple actions like getting yourself a reusable drinks bottle.

2: HDPE

Again, this is a commonly recycled kind of plastic. Unlike PET, it doesn’t break down easily under sunlight so it's much safer and ideal for use in outdoor products. It can now also be turned back into food-grade plastic.

Like PET though, it’s a reasonably easy one to avoid: have milk delivered by a milkman, and opt for shampoo bars and soap bars.

HDPE symbol

Look carefully on the underside of this kitchen cleaner and you'll spot the HDPE symbol

3: PVC

Are window frames the first thing that spring to mind when someone mentions PVC? Handy as it is, PVC, also known as vinyl, is a big problem. It contains some pretty unpleasant chemicals and is difficult to recycle, besides the fact it releases pollutants during manufacture.

So what can you do about it? One of our favourite solutions is to simply swap single-use PVC cling film for reusable beeswax wraps.

4: LDPE

LDPE is super flexible, which makes it perfect for things carrier bags. Unfortunately though, Plastic film isn’t accepted by a lot of councils in kerbside collections (although you may well find that your local supermarket has a collection point for carrier bags and similar films).

The easiest ways of avoiding LDPE are to carry your own travel mug with you, swap from sandwich bags to beeswax wraps or paper sandwich bags, and bring a reusable bag to the shops. And we’re not just talking about your main shopping bag – grab yourself some reusable fruit & veg bags as well to avoid those plastic bags the supermarket doles out in the veg aisle!

5: PP

Polypropylene is tough and light, making it very versatile and the best plastic for creating “living hinges” aka the flip-top cap on a water bottle. This means that one of the easiest ways of cutting down on PP is to simply carry your own reusable water bottle with you. It’s also common in disposable nappies (if you feel up to the challenge, try cloth nappies instead) and plastic straws (remember to refuse plastic straws at bars and restaurants).

PP symbol plastic pot

The PP symbol on the base of a yogurt pot

6: PS

You’re probably pretty familiar with polystyrene, right? It’s light, cheap to produce and easy to mould. But these properties come at a cost: polystyrene breaks apart incredibly easily, making it a massive problem for marine species, which often mistake it for food.

Carrying your own reusable coffee mug is a good way to avoid those ubiquitous Styrofoam cups, while choosing retailers who ship in eco-friendly packaging will reduce the number of polystyrene packing peanuts you end up with (if you end up with a box of packaging peanuts, run one under a tap. If it dissolves, it’s made from corn starch or wheat, rather than polystyrene, and can be composted).

7: Other

This category covers a whole load of kinds of plastic. One of the naughtiest kinds in this category is BPA, which is known to leach into food and drink, and so is definitely to be avoided.

Confusingly, this category also includes bioplastics – plastics made from things like corn starch, rather than from oil. They’re generally marked with the letters “PLA” next to the resin identification code. Bioplastics can be composted in industrial composting facilities, but these aren’t available in every area. And if they get into the recycling stream, they can reduce the quality of the recycled output.

PET symbol plastic bottle

This bottle of cooking oil is made from type 1 plastic: PET

Over to you…

All that remains now is to use your newfound knowledge to prioritise the products you buy and avoid those that are least recyclable! Oh yeah, and don’t forget to read our blog article on on-pack recycling labels, which should make it even easier to identify whether or not you can recycle the stuff you’re buying.