Plastic number 6 - polystyrene

Plastic number 6 - polystyrene

Polystyrene is a plastic with a mixed message.  On the one hand, foamed PS is an excellent insulator and is used more and more in buildings to provide savings by reducing heat loss in winter and promoting cooler buildings in summer.  That's terrific, but other uses of foamed PS aren't so green. 

I'm old enough to remember McDonald's bringing in 'clam shell' hamburger containers to replace cardboard boxes because of concerns over how much rainforest was being cut down to make paper and cardboard, only to replace the clam shells some years later over concerns about the amount of non-biodegradable litter they generated.  When so many of the ways we use a plastic are single use then we have a problem. 

Foamed PS is used to make boxes to transport fish and vegetables (because they are light, insulating and melting ice doesn't make them soggy), takeaway food containers and cups, and packaging 'peanuts' and frames (lightweight and protective).  As you unpack your new computer or flat screen you ponder what to do with the waste packaging.  There's no way to recycle it presently, so it ends up in landfill.  And because it is lightweight, polystyrene packaging often ends up blowing into the ocean, where it floats.  PS is particularly resistant to photo-degradation, so it doesn't break down and is toxic to any animal that ingests sufficient quantities.  Large amounts of packaging from fish markets and factories where beads of PS are produced end up polluting the oceans.

A little PS is able to be recycled in the Council waste collection, mainly the foamed trays used to package meat and vegetables, yoghurt tubs and the containers used to package tomatoes and strawberries, but the vast majority of PS ends up in landfill.

Crystal CD cases, disposable cutlery, plastic wine glasses and  are made of PS. In this form, it's quite brittle and so even uses that are a little more long term, such as CD cases, tend to generate a lot of waste.

There are alternatives to many of these uses, from Keep Cups for a take away coffee, to bamboo or wooden cutlery for picnics.  We still see some polystyrene packing peanuts at ZURI, but we usually let our suppliers know that they can get the same benefit from packing peanuts made of corn.  These break down really quickly in the garden and make a good additive to compost. We are pleased to have seen some suppliers make changes in this regard. Because so much of the PS we come into contact with is non-negotiable - try buying a computer without all that foam shock absorber - it's important to think carefully about our use of PS in the areas where we can make a difference.