What Are The Plastic Symbols?

Plastics these days are required to have a symbol stamped on them. These triangular marks are a subset of a larger set of recycling marks that include paper etc. For the purposes of home recycling, only four are really suitable, and only three are simple to work with. These are their symbols, this is how you can tell.

Oh and don’t expect bottle caps to all have markings, sometimes you just have to apply your knowledge of how flexible or inflexible a plastic is, the sheen of it, and make a decision. For our purposes only 1, 2, 4, and 5 are useable.

Some Recyclable Plastics

HDPE (High Density PolyEthylene) is what most bottle caps (drink and sauce bottle, Vegemite, honey, and peanut paste jar lids) are made from. Also vitamin bottles and their lids, big tomato sauce jugs are generally made of HDPE as are vinegar and milk jugs, and the lids and bodies of cream tubs are generally HDPE or LDPE, both of which can be recycled.

That gets us to PolyPropylene. Some lids are made from this plastic, it’s a harder shinier plastic than HDPE or LDPE. Other stuff made from PP includes all those plastic pots you get plants from the nursery or Bunnings in, not the really thin soft crinkly kind though because for some reason they just don’t work. One day I hope to be able to accept PP as well.

Low Density PolyEthylene gets used for some drinks lids and is generally fine to recycle. Some department store shopping bags are made from LDPE but I can’t easily process those. Yet…

PET PolyEthylene Tetrafluoride (yeah, really) is the clear plastic drink bottles are made from and that you can hand back in for the 10c rebate. — minus their caps, of course, which I’ll happily take.

The Others

Type 7 (the dreaded “Assorted” plastics that you never know what’s in them) and ABS are either impossible to recycle on a small scale or else give off toxic fumes.

Type 3 (PVC, PolyVinyl Chloride) and Type 6 (PS PolyStyrene) are really nasty, very toxic, fume agents that you just don’t want to mess with, and are the #1 poison fumes sources in house fires. They don’t just give off toxic fumes when they’re on fire, but also just when they get hot enough to melt, unless you have very well-controlled heating.

Those Type 7 plastics. Sometimes they’re just PE of either kind but with additives. Sometimes the additives are plain to see (such as glitter or carbon fibre embedded in the plastic) but often they’re plasticisers to make a softer more flexible product, sometimes it’s the dye they used and which will contaminate future recycling. That’s a reason we tend to leave unmarked or Type 7 plastics alone.

The problem is that manufacturers aren’t required to list the additives, which would help with recycling but some plastic items might end up with 30 or more stamps on them. It’s a BS situation but we’re stuck with it. Better to leave unmarked or Type 7 plastics alone. And PVC. And PS – PolyStyrene – the stuff that foam insulated cups are made of, aka Type 6. PS also releases toxic fumes and is hard to recycle because you need so much of the expanded PS to get just a cupful of the liquid (solid) plastic.

Links:

Recycling Symbols on Wikipedia. A fairly comprehensive list.