Bags not! Finding the solution for Australia’s plastic bags

Plastic BagsThe recent Ministerial Roundtable on plastics could not agree whether to ban, price or leave Single Use Plastic Bags (SUPBs) for another day. We use approximately 6 billion SUPBs each year, of which 2 percent are recycled[i].

SUPBs are being, or have been, banned in South Australia, Tasmania, the ACT, the Northern Territory and in some localised townships.

The choice of ban vs. price (say a 10 cent levy) is one of economic efficiency. Bans are black or white, while pricing leaves room for progressive behaviour change and infrastructure development, while potentially raising money for worthy causes.

But it is pretty clear that there is finally a national appetite to address SUPBs. Whether agreed or not, it is important that we get the transition right. Let’s be very careful that we do not replace 6 billion SUPBs with something that doesn’t work. We still need to go shopping.

Also many councils are now offering householders Food Organics and Garden Organics (FOGO) collection bins to recover the 60% of organics an average household generates. These 3 bin services usually involve a small kitchen tidy and the supply of bio-bags. The FOGO that is collected is usually taken to a large composting facility. SUPBs are a big problem in composting facilities, but so are many of their so-called alternatives.

So if we do away with SUPBs, what do we replace them with, especially for our shopping and FOGO services?

The alternatives

The short answer is we need to replace them with compostable bags. What does that mean?

In the Australian marketplace we talk of ‘degradable’, ‘biodegradable’ and ‘compostable’ bags. There are also ‘oxo-degradable’, ‘solar-degradable’, ‘recycled’, ‘recyclable’ and ‘reusable’. Not much help.

They are not equal. They are not the same and most of these gum up composting facilities.

A ‘degradable’ bag is usually made from plastic, such as polyethylene, with a polymer added to ensure breakdown over time (after exposure to light, oxygen and heat) into small fragments. They break down to create lots of small bits of plastic (micro-plastic) which are as bad, if not worse than SUPBs.

They are also a complete pain in composting facilities. Since it breaks down into micro-plastic it contaminates the finished compost product.

Bottom line – ‘degradable’ bags are not a good solution.

Some plastics manufacturers include additives to accelerate degradation and label these bags as ‘biodegradable’. However, the term ‘biodegradable’ is very loosely used.

The School of Packaging at Michigan State University summed it up well: “The ultimate goal of biodegradation is to totally break down the molecular structure of the polymer, returning the carbon in the plastic to the normal geological carbon cycle. In many cases, biodegradable bags do not achieve this state and leave behind physical residue in the form of micro-plastic (typically any piece of plastic less than 5mm long and sometimes not visible to the naked eye), including microbeads[ii].”

Bottom line – ‘biodegradable’ is not a reliable definition for something that will compost and not pollute.

‘Compostable’ bags on the other hand, are made from plant material such as starch[iii]. They break down completely into ‘humus’, carbon dioxide, heat and water.[iv] (they also fully decompose in composting facilities).

The Australian Organics Recycling Association (AORA) supports a ban on all SUPBs. Similarly, it seeks confirmation that all replacement products are ‘compostable’ and meet the requirements of Australian Standards 4736 and AS5810 for composting.

Bottom line – ‘compostable’ replacements offer a viable alternative.


We have got to get this transition right.

Organic waste represents over 50 percent of all waste we landfill, or 10 million tonnes. It is 60% of what an average household generates.

Organic waste in landfill breaks down anaerobically, to generate methane, which if not captured, leaches into the atmosphere. Methane is a potent greenhouse gas (25 times the global warming potential of carbon dioxide) and accounts for 11 million tonnes of Australian greenhouse gas emissions per annum.

There are transition issues we need to consider. It is true that until we get national FOGO bin servicing, that many compostable bags will end up in landfill and contribute a tiny amount to methane generation. But they are such a small percentage of landfill tonnages (0.1%), that their contribution during the roll out of FOGO nationally will be negligible.

Councils and food retailers with food or organics collection services, need to ensure their tenders specify ‘compostable’ bags that meet AS4736.

So here is the takeaway message. A compostable bag is biodegradable. But a biodegradable bag is not necessarily compostable. So if it is not certified ‘compostable’ – don’t use it.

As always, I welcome your feedback on this, or any other topic on ‘The Tipping Point’.

[i] Banning plastic bags – the tip of the iceberg –

[ii] ‘Biodegradable’ plastics don’t live up to manufacturers’ claims –

[iii] Compostable vs degradable. Whats in a name? –

[iv] The difference between biodegradable and compostable packaging materials –

2 thoughts on “Bags not! Finding the solution for Australia’s plastic bags

  1. Great topic and one dear to my heart….after a trip to the landfill and see the year layers of good old plastic is just mind blowing and a sight that more of the public should see. Now with so many separeated waste and recycle centres not many people get to see what is actually ending up in our /their landfills. I still struggle with the fact that South Australia banned plastic bags many years ago and it is working really well…….so why are other states having such an ordeal with implementing legislation to banning SUPB’s??? I don’t get it. I work /live on the Gold Coast Qlds,( in Waste in Council). Target shops tried stopping plastic bags here for a short time, but copped so much flack, apparently, from customers that they bought them back in !!! True they gave it a shot but dint stick it out. surely their is a cost reduction to the business if you are not supplying the bags….they don’t come free!!! as many people seemed to think. At the end of the day, like SA people, everyone here would just get used of it……look at Aldi… yes you can buy their plastic bags and yes people complained for a awhile about how inconvenient it was for them not to have free plastic bags but look at Aldi those shops are packed with people who take their own “grocery buying transport containers” now and it shows that while people whinge about change they just get used of it and DO IT/CONFORM in the end. We should be showing people what happens at waste landfills, show the differences in what happens to recyclable items. I deal with people all day everyday and talk about recycling, people don’t understand the difference in most cases they still think that even though we have different trucks to pick up waste and recycling, it still ALL goes to landfill, I still get amazed at how many people have no idea why they are asked to separate their waste, when I talk to groups about waste it is amazing what is not known and how much people want to know……..we have a long way to go to educate people on the ‘whys’ and ‘how’s’. Thank you to the likes of Planet Ark, Keep Australia Beautiful, and Clean up Australia Day etc. events/advertising, but it needs to come back to the manufacturing, if excess packaging, and often not warranted, amounts were not allowed in the first place we wouldn’t have half the battle. for all us “waste-soldiers” we will need to just keep chipping away at the problem doing the best we can until our younger generations grow up with the knowledge and value of ……..AVOIDANCE, REUSE. REDUCE, RECYCLE.

  2. Another excellent and well researched article from The Tipping Point. I think separating waste at the point of generation can deliver the most effective results. Separation of waste streams by households has improved vastly over the past few decades. Strong support and actions by Local and State Governments over this period has contributed greatly to influencing householders to change their habits. Unfortunately this seems to change when people are in their workplace. With 50% of waste to landfill being organic, there is a great opportunity for the separation of organics by Food Businesses in the C&I sector, which currently send large volumes of organics to landfill.

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