Why Plastic Recycling Doesn't Work

19th April 2023

“The sad truth is that less than 10% of everyday plastic – the plastic packaging that the things we buy is wrapped in – actually gets recycled in the UK”

Greenpeace activist stands on an heavily polluted beach with a sign which reads, 'This is what plastic pollution looks like'
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Recycling rates for plastic have always been very low. This is in contrast to metals and glass which have always had high rates or reuse. But why? Basically it comes down to the nature of plastics.

Different Plastics Cannot Be Recycled Together

There are thousands of different kinds of plastics. If you look on any item of plastic packaging you will usually find a code number set in a little rounded triangle, with a short letter code underneath. This is the resin identification code, NOT a recycling symbol. For example, 1 (PET) means the plastic is polyethylene terephthalate, mainly used for water and soft-drink bottles. 2 (HDPE) is high density polyethylene used in milk, shampoo and detergent bottles. And so on, up to 7 (other) a catch-all category for items either with a mix of plastics, or which are made from one of the thousands of types of less common plastics.

Mixed plastics cannot be simply recycled together. They need to be separated for different recycling processes. Some cannot effectively be recycled at all. This gives rise to a massive problem of identifying and sorting prior to processing.

Resin ID code 01: PET
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However, the plastics used in many items are not easily identifiable. Worse still, many plastic items do not even carry an identifying code.

The cost of sorting and separating waste plastics by type is a major barrier to recycling.


Plastics tend to absorb chemicals with which they come into contact. Many plastic containers have printing on and the chemicals used in the inks complicate recycling processes. A greater problem still is that plastic containers used for oil or cleaning products cannot be recycled because of the toxins that they will have absorbed while in use. Plastics in ordinary waste may also have have absorbed toxins from other items they have been in contact with.

Worn plastic
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Consequently, recycled plastics are generally of poorer quality and restricted in how they can be used. Most food packaging, for example, cannot be recycled to produce new food-grade packaging.

As a Result...

...plastic is generally more expensive to recycle than to make. And recycled plastics do not have as wide a range of uses as completely new plastics.

This is reflected by the reality of current recycling where only certain types of plastic — easily identifiable and economical to process — are recycled in any quantity. Mainly 1 (PET) and 2 (HDPE) plastics.


All plastic recycling processes pollute.

For example, the mechanical processing of plastics which is a necessary first step — shredding plastic into uniform sized chips to be washed — produces microplastic particles which pass into the environment with the used water. A study of a UK plastic recycling facility estimated that up to 75 billion microplastic particles were being released into each cubic meter of wastewater. That was with a filter installed.

Plastics are highly flammable so there is always the risk of fires at plastics recycling plants or in transit, which caused devastation in Ohio, USA in 2023.


The best way to deal with plastic is to avoid using it in the first place.

Sign which reads 'Don't use plastic, be fantastic'
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Once used for packaging or in some other item, it is not currently possible to deal with plastic in an environmentally safe way. Of course, plastic use is so widespread that it is now hard to envisage a world without plastics. However, without incentives to look for other ways of distributing food (for example in reusable containers — milk used to come in glass bottles that were easily reused), to reduce plastic use in products or to ensure the reusability of some plastic items, we are likely to be stuck in a situation where the impacts of plastic on pollution and climate change continue to grow.

Refill Swindon logo
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It is a false economy to put the future of the planet at risk because of the short-term costs of moving away from dependency on plastics.

Further learning

This article is largely based on information from “Circular Claims Fall Flat Again”, Greenpeace US, 2022