Do You Know Which Plastics Can Be Recycled?

It’s an accepted ritual in every suburb in Australia where the local authorities provide a separate bin for recycling - separate the recyclable material, put it in the bin with the yellow lid (or whatever other colour differentiates it from household rubbish), and wheel it onto the footpath on collection night. Most bins contain a mixture of cans, paper and plastics, and while most householders don’t have too much trouble deciding on the recycling suitability of the other materials, plastics can sometimes be a challenge. Most of us don’t really know a lot about the different properties of plastics so it’s not surprising that we often don’t know which ones are recyclable.

Most plastic sent for recycling is reprocessed into useful products, sometimes in a completely different form from the original material. For example, food packaging could go through the recycling process and end up as another product entirely. It all depends on what the original plastic is made of and what type of process it must go through to be reused as different types of plastic require different processing.

The easiest way to identify suitable plastics is to look for the PET code, a triangle of arrows with a single digit number from 1 to 7 in the centre. Designed in 1988 by the Society of the Plastics Industry, it gives consumers and manufacturers a uniform coding system for differentiating types of plastics.

The most commonly recycled plastics have the numbers 1, 2 and 5 on the PET code. The number 1 is given to plastics made of polyethylene terephthalate, the easiest and most common plastic to recycle. Soft drink and water bottles and many other common consumer product containers are recycled into fiberfill used in sleeping bags. Number 2 is high-density polyethylene, a heavier plastic found in containers that hold laundry detergent, also milk, shampoo and motor oil. This plastic is hard to semi-flexible, is usually white or coloured and also relatively easy to process.

Polypropylene is number 5 and is strong, tough, resistant to heat, chemicals, grease and oil, and is a barrier to moisture. Many household items fall into this category including reusable microwaveable ware, yoghurt containers and margarine tubs, disposable take-away containers and disposable cups and plates.

This doesn’t mean the end of the road for the other plastics and as technology keeps improving, some local Councils are able to recycle 3, 4, 6 and 7. Frozen food bags made of low density polyethylene are a 4 and currently are the only plastic bags in Brisbane recycling stations will accept. The sticker on the recycling bin should give more details.

When all types of plastics can be recycled it will go a long way to reducing our landfill, our energy consumption and hopefully the cost of packaging to the consumer.