The future of plastics: reusing the bad and encouraging the good


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Plastic pollution: discarded plastic bags are a hazard to marine life.
Richard Whitcombe/Shutterstock, CC BY-ND

Kim Pickering, University of Waikato

Plastics have got themselves a bad name, mainly for two reasons: most are made from petroleum and they end up as litter in the environment.

However, both of these are quite avoidable. An increased focus on bio-derived and degradable composites as well as recycling could lessen pollution and, in fact, plastics could make a positive contribution to the environment.

Plastics for bad

The durability of plastics makes them so useful, but at the same time, it turns them into a persistent (and increasingly big) blot on the landscape, or more importantly the seascape, once discarded.


Read more: This South Pacific island of rubbish shows why we need to quit our plastic habit


We’ve known for a while that bulk plastics are polluting the oceans. Converging sea currents are accumulating plastic waste in a floating island known as the Great Pacific Garbage Patch, which now covers an area larger than Greenland. The bigger bits of plastic are life-threatening to marine life and sea birds. They can strangle marine mammals or birds and build up in their stomachs and guts.

A dolphin entangled in fishing line and plastic bags (Indian Ocean).
from Shutterstock, CC BY-ND

More recently, awareness of microplastics has raised concern about their ubiquitous presence in the food chain. Commentators suggest that by 2050 there will be as much plastic in the sea as there is fish. Who wants to go catch some plastic then?


Read more: How microplastics make their way up the ocean food chain into fish


Beyond that, plastic production currently relies on petroleum and that has raised issues about health hazards, generally associated with petroleum-based products during production, use and disposal.

Plastics for good

Plastics can contribute positively to the environment in the following ways:

  • Reduced food wastage

Between one-quarter and one-third of all food produced is wasted through spoilage. But without plastic packaging, it would be considerably worse and have a larger carbon footprint.

Many of the recycling enthusiasts I know do not think about throwing out spoiled food that required energy in terms of planting, cultivating, harvesting and transporting and therefore will have added to greenhouse gas emissions.

  • Lightweight transport

The use of plastics in transportation (cars, trains and planes) will reduce fuel consumption. Their application (along with reinforcing fibres) in aerospace as alternatives to traditional metallic alloys has brought huge gains of fuel efficiency over the last few decades.

Incorporation of fibre-reinforced plastics in the Boeing 787 Dreamliner, for example, has resulted in fuel efficiencies that are similar to a family car (when measured by kilometres travelled per person). By the way, carbon fibre, the aerospace fibre of choice, is produced from plastic.

There are good things about plastics including benefits for the environment, but is it possible to make use of the good aspects and avoid the bad?

Future proofing plastics

Plastics are, chemically speaking, long chains or large cross-linked structures most commonly made up of a framework of carbon atoms.

For a long time, we have been using bio-derived plastics – naturally occurring materials such as animal skins including leather, gut and wood. These forms of plastic are complicated chemical structures that can only be made in nature at this stage.

Some of the early synthesised plastics were made from naturally occurring materials such as casein (from dairy) that was used for simple items such as buttons. The development of petroleum-based plastics has been a major distraction from such materials.

However, in the last couple of decades, bio-derived plastics have become available that provide good replacements. These include starch-based plastics such as polylactide (PLA), which is produced from corn starch, cassava roots or sugarcane and processed in the same way as petroleum-based plastics. Such plastics can be foamed or used to make drink bottles.

Plastic bottles ready to be recycled.
From Shutterstock, CC BY-ND

Recycling plastics is another essential step towards reducing the environmental load. Let’s face it: it is people who are doing the littering, not the plastics themselves. More effort could go into waste collection and a carrot/stick approach should include disincentives for littering and a plastic tax which would exclude recycled plastics.

Incentives are also needed to encourage product development that takes account of the full life cycle. In Europe, for instance, legislation has made it compulsory in the automotive industry for at least 85% of a car to be recycled. This has had a dramatic influence on the materials and design used in the industry.

Even with best efforts, it is unrealistic that we would capture all plastics for recycling. Biodegradable plastics could be a useful tool for preventing environmental damage. PLA (polylactide) is biodegradable, though slow to break down, and there are other forms available.

This highlights the need for more research into controlling biodegradability, taking into account different applications and the need for infrastructure to deal with biodegradable plastics at the end of their life. Obviously, we don’t want our planes biodegrading during their 20 years of service, but one-use water bottles should break down within a short time after use.

The planet doesn’t have to become a toxic rubbish dump. In the short term, this will need some government action to encourage bio-derived, recyclable and biodegradable plastics to allow them to compete with petroleum-based products.

The ConversationThere are signs of improvement: increasing awareness of the harm plastics cause and a willingness of consumers to pay for plastic bags or to ban them. We need to stop dumping in our own backyard and remember that the environment is where we live. We ignore it at our peril.

Kim Pickering, Professor of materials science and engineering, University of Waikato

This article was originally published on The Conversation. Read the original article.

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Victoria’s plastic bag ban: a good start, but we can do more



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The Victorian government has a new proposal to ban plastic bags. What is it missing?
suvajit/pixabay, CC BY

Trevor Thornton, Deakin University

The Victorian government is proposing to ban single-use lightweight plastic shopping bags.

First of all, for plastic bag devotees, don’t panic – there are alternatives such as paper, cloth and a range of other reusable bags (you can even use the cardboard cartons from the shop). For those who have been advocating for a ban, don’t relax – there is still more to be done.

While the details of the plan are still being discussed, it is good to see that the government has committed to consultation with businesses and the community. We can be assured that the government will not swap one issue for another – such as reducing the amount of plastic bags used for waste, only to increase the use of bin liners. We need to ensure that the alternatives proposed actually reduce environmental impact.

In fact, this is prime time for the government to take a step further. We can do much more than ban single-use plastic bags. We should expand the ban to cover more categories of plastic and actively move to manage waste and reduce plastic pollution.


Read more: Getting rid of plastic bags: a windfall for supermarkets but it won’t do much for the environment


Should the ban proceed, it will have one significant outcome. The three most common contaminants of the household recycling bin (representing 10-15% of the recycling stream, according to my own audits of kerbside recycling bins) will be banned:

  • plastic bags with recyclables
  • plastic bags with general waste
  • empty plastic bags.

But simply looking at the perceived issues associated with plastic bag disposal is not enough. We must also understand why people actually use plastic bags. What are their shopping habits? When do they shop? Have we considered tourists who buy groceries?

Plastics ban is not enough

Instead of just banning bags, we need to look at the issue of plastic in its broadest sense. On a recent trip to the supermarket, I estimated that almost 40% of the vegetables are wrapped in plastic packaging. Even if you wanted an alternative, sometimes there isn’t one. The packaging comes with the produce.

Excessive plastic packaging around groceries. Is it necessary?
Anna Gregory/flickr, CC BY

The Victorian government has claimed that it would be impractical to ban the packaging of fruit and vegetables. But why is it acceptable to focus only on the plastic in bags and not in other vessels? Packaging is another source of excess plastic that consumes resources and contributes significantly to landfill waste. Given that many foods (such as strawberries or tomatoes) are pre-packaged, shoppers will often buy more than they need and end up wasting food.

We have the perfect opportunity to address two significant issues at the same time. The question is: will we?

The Victoria government has acknowledged that thicker, more durable plastic bags have a greater environmental impact. Yet according to the proposed policy, the banning of these bags may be optional. This is why any consultation process must encompass all types of plastic.

Is all this plastic really necessary?
Anna Gregroy/flickr, CC BY

We have the opportunity to get it right and lead the way, and it is important that all views are heard. If you would like to have your say, the Victorian government has a survey where comments can be provided.

What we can learn from other programs

When looking at programs that successfully changed our behaviour, such as “slip slop slap”, using seatbelts and reducing the road toll, promoting HIV awareness, and even litter prevention, we can identify several features that seem to be crucial to their success. They are:

  • the program advised us exactly what to do and why
  • there were multiple different advertisements – but each focused on the same issue
  • different demographics were targeted, but with the same focus
  • the advertisements were provided in multiple formats at many locations.

It will be important that any action undertaken includes an education program. It should inform consumers why this ban is happening and advise them what actions they can take.

Other policies that we can undertake include container deposit legislation. My audits of SA’s landfill rates, compared with those of other states without container deposit schemes, shows that these schemes significantly reduce the disposal of plastic waste to landfill.

These changes should be incorporated into the proposed ban of the plastic bags. We must learn from past policies to ensure we make a smooth transition away from disposable plastics. The government should be aware of the different shopping habits of our society to find a cost-effective yet sustainable solution to plastic packaging.

The ConversationThere are a lot of changes that we can make. It is not just limited to banning single-use plastic bags. We need to consider the bigger picture of plastic packaging so we can truly put a dent in retail waste.

Trevor Thornton, Lecturer, School of Life and Environmental Sciences, Deakin University

This article was originally published on The Conversation. Read the original article.

In banning plastic bags we need to make sure we’re not creating new problems


Trevor Thornton, Deakin University

The recent decision by Australia’s big two supermarkets to phase out free single-use plastic bags within a year is just the latest development in a debate that has been rumbling for decades.

State governments in Queensland and New South Wales have canvassed the idea, which has been implemented right across the retail sector in South Australia and the Australian Capital Territory.

So far, so good. But are there any downsides? Many of you, for instance, face the prospect of paying for bin liners for the first time ever. And while that might sound tongue-in-cheek, it shows the importance of considering the full life-cycle of the plastics we use.

Pros and cons

On a direct level, banning single-use plastic bags will avoid the resource use and negative environmental impacts associated with their manufacture. It will reduce or even eliminate a major contaminant of kerbside recycling. When the ACT banned these bags in 2011 there was a reported 36% decrease in the number of bags reaching landfill.

However, the ACT government also noted an increase in sales of plastic bags designed specifically for waste. These are typically similar in size to single-use shopping bags but heavier and therefore contain more plastic.

Ireland’s tax on plastic shopping bags, implemented in 2002, also resulted in a significant increase in sales of heavier plastic waste bags. These bags are often dyed various colours, which represents another resource and potential environmental contaminant.

Keep Australia Beautiful, in its 2015-16 National Litter Index, reported a 6.2% reduction in the littering of plastic bags relative to the previous year, while also noting that these represent only 1% of litter.

Meanwhile, alternatives such as paper or canvas bags have environmental impacts of their own. According to a UK Environmental Agency report, a paper bag would need to be re-used at least four times, and cotton bags at least 173 times, to have a lower environmental impact than single-use plastic bags in terms of resource use, energy and greenhouse outcomes.

This illustrates the importance of considering the full life cycle of shopping bags to arrive at an evidence-based decision rather than one based on emotion or incomplete data. I am not suggesting this is the case with plastic shopping bags; I’m just pointing out the value of proper analysis.

Simply banning a certain type of bag, while this may be a good idea in itself, could result in other knock-on impacts that are harder to manage. Replacing shopping bags with heavier, more resource-intensive ones may solve some environmental impacts but exacerbate others.

Plastics, not plastic bags

In a 2016 discussion paper, Western Australia’s Local Government Association suggested that the focus of action should be plastics in general, not just shopping bags.

As the Keep Australia Beautiful data show, plastic bags are just a small part of a much bigger problem. Many other plastic items are entering the litter stream too.

With this in mind, it pays to ask exactly why we are banning plastic shopping bags. Is it the litter issue, the potential impact on wildlife, the resource consumption, all of the above, or something else? Is it because they are plastic, because they are disposable, or because it saves supermarkets money?

The answers to these questions can guide the development of an effective strategy to reduce the environmental (and perhaps economic) burden of taking our shopping home. With that in place, we can then develop an education strategy to help shoppers adapt and make the scheme a success. But this costs money.

The triple bottom line

There should be plenty of money available. The Victorian state government’s Sustainability Fund, for instance, has A$419 million to spend over the next five years on researching alternatives to shopping and household waste management. Developing a shopping bag strategy would consume only a small part of this and would be money well spent.

The concept of the “triple bottom line” – ensuring that decisions are based equally on environmental, social and economic considerations – needs to be applied to decisions about whether to ban single-use plastic bags, and what alternatives will result. The problem with simply announcing a ban is that this leaves it up to shoppers themselves to work out what to do to replace them.

Evidence-based policy is crucial. We first need to find out how many people already use re-usable bags, whether they always take them to the shops, and what items they put in them. Do people generally know how many times each type of bag should be re-used in order to be an environmentally better choice than the current plastic bags? What’s the best material for re-usable bags, taking into account not only their environmental credentials but also their ability to get your shopping home without breaking?

The ConversationWhen it comes to environmental impacts, it’s important not to simply exchange one problem for another. If all we’re doing is swapping between different types of plastic, it’s hard to see how we’re solving anything.

Trevor Thornton, Lecturer, School of Life and Environmental Sciences, Deakin University

This article was originally published on The Conversation. Read the original article.

How ‘nudge theory’ can help shops avoid a backlash over plastic bag bans


Daniela Spanjaard, Western Sydney University and Francine Garlin, Western Sydney University

On your way home tonight, you might stop at the supermarket to grab some ingredients for the evening meal. If you’re like many shoppers, you’ll pass through the self-service checkout, scan your items, and hurriedly place them in the conveniently waiting thin, grey plastic bag before finalising the purchase.

At home, the purchases are packed away or lined up for immediate preparation. The plastic bag is scrunched into a little ball and stuffed away with others in your collection, to be used as bin liners or otherwise thrown away. All of these behaviours are, by and large, done without a great deal of thought.

One of the most challenging tasks for marketers is to bring about changes in consumer behaviours that have become habitual, routine and “low involvement” – why spend time stopping and considering various brands of laundry detergent, for instance, when you can just quickly grab the one you’ve always used?

The very nature of habitual behaviour means that responses to the same situational cues happen automatically and with little conscious thought. Habits are powerfully ingrained. One study estimates that around 45% of our daily actions are habitual, and most of our purchases and consumption is of the low-involvement variety.

Repetitive consumer behaviour is a tough cycle to disrupt. And it is the very nature of these habitual responses that make many standard interventions relatively ineffective.

But this is the task facing supermarkets in taking away customers’ access to free plastic bags.

Banning the bags

The recently announced plans by supermarket giants Coles and Woolworths to ban single-use plastic bags seem admirable enough, but the environmental benefits will only be fully realised if the ban drives a permanent change in shoppers’ behaviour.

Many countries have tried a variety of strategies to get rid of single-use plastic bags, including bans, educational campaigns, and levies. Most have had mixed results. There is no overwhelming evidence to suggest that any of these approaches has fully broken shoppers’ disposable bag habit.

Even where use has been dramatically reduced, the environmental impact has been mitigated by unintended consequences such as a 65% increase in the purchase of bin liners, and the disposal of re-usable bags. And despite a general shift in attitude towards environmentally sustainable consumption, this “intention-behaviour gap” still prevails.

Breaking the habit

Here is where some behavioural psychology can be brought to bear on the problem. We know that habitual behaviours are learned and reinforced through repeated responses to particular situations. Theoretically, if these behaviours are learned, they can be unlearned by providing different situations.

One potentially useful technique is called “nudging”. A nudge gives people a gentle prod to change their behaviour, through encouragement rather than coercion. This sometimes controversial subject is most familiar in terms of behavioural economics – a classic example being the small refunds offered by drink bottle recycling schemes – but nudges can be purely behavioural as well as economic.

Behavioural nudges aim to make people stop and think about what would otherwise be an unconscious behaviour. Often this takes the form of a short, simple message. Electricity providers have been known to use this method of nudging. Power usage by their customers will drop when they are shown that the usage rate of a similar-sized household is more efficient than their own.

But it can also involve a minor adjustment to the environment in which the behaviour occurs. Such a strategy could be applied in supermarkets where “footprints” could lead to reusable bags that are available for purchase. Repeating this over time could result in consumers associating the footprints with a reminder to bring their own bags. Varying the location of the footprints, or even their colour or shape, might encourage shoppers’ curiosity and thus increase the likelihood of consciousness about the plastic bag ban.

Economic nudges can also be used to help shoppers quit plastic bags – as in the case of Toronto, which introduced a 5-cent levy on plastic bags. There are many ways to gently encourage shoppers to make better decisions.

Australia’s big shopping brands

Given that much of the problem involves challenging current behaviours, it stands to reason that the big brands’ responses to this question will hinge on what their customers are already used to.

Retailers such as Bunnings and Aldi have never provided their customers with free, disposable plastic bags. Their customers learned quickly from the outset to use alternatives, such as the stash of old cardboard boxes typically found behind the checkouts at Bunnings.

Woolworths and Coles, on the other hand, face a tougher challenge. They are taking something away from shoppers, and some customers may be resentful and resistant to change as a result.

To avoid a repeat of Target’s aborted effort to remove free bags in 2013, Coles and Woolworths might find that the best way to avoid a similar customer revolt is to use in-store cues as behavioural nudges, alongside the economic incentive of offering durable plastic bags for a price. Many consumers will be willing to pay for plastic bag alternatives during the transition phase. Combining this with gentle reminders such as in-store “footprints” will aim to gradually change those low-involvement, highly habitual shopping patterns.

The ConversationWhether economic or non-economic, messages to shoppers need to be as pervasive and repetitive as the ingrained behaviours they are trying to change.

Daniela Spanjaard, Director of Academic Program, Hospitality, Marketing & Sport, School of Business, Western Sydney University and Francine Garlin, Director of Undergraduate Programs, School of Business, Western Sydney University

This article was originally published on The Conversation. Read the original article.

Getting rid of plastic bags: a windfall for supermarkets but it won’t do much for the environment


Gary Mortimer, Queensland University of Technology

Moves by major supermarkets to stop providing free plastic bags could earn these businesses more than A$1 million a year, but may only have a small impact on the environment.

Australia’s two supermarket giants, Woolworths and Coles, have announced that their stores will stop offering their regular plastic bags within 12 months. Instead, customers will be able to buy a more durable plastic bag at 15 cents apiece, or simply bring their own.

These bags are factored into the cost of doing business for these supermarkets. There are costs beyond just the bags themselves, such as the costs associated with sourcing and negotiating with packaging suppliers, procuring them, shipping and warehousing them, and distributing them to stores only to then give them away.

Supermarket margins are already feeling the strain of price deflation. These businesses are generally making less than 6c in the dollar, so the opportunity to phase out this cost certainly makes good business sense. The table below provides an estimate of current costs.

Estimated current costs

https://datawrapper.dwcdn.net/nCISJ/1/

While retailers stand to pocket this saving, the switch to stronger, multi-use plastic bag brings with it its own costs. To begin with, the bags alone cost more (9c each) and also have associated procurement costs.

However, the new scheme will immediately reduce customers’ bag usage. Being optimistic, it would be reasonable to see an 80% decline in plastic bag use as shoppers actively search for alternatives to free bags.

Most shoppers will probably reuse the 15c bag, or look to other options like canvas bags, polyethylene bags or cardboard boxes. In turn, while the new re-usable bag may cost more than the thinner single-use bag, fewer will be used and therefore ordered. Retailers can expect to see a reduction in these packaging costs.

Estimated costs under new scheme

https://datawrapper.dwcdn.net/8EiSX/2/

It’s estimated that Australian retailers give away 6 billion plastic bags each year. Woolworths alone say they provide 3.2 billion each year. Coles has not provided an estimate of bag use, but claim to process 21 million transactions each week. With fewer stores than Woolworths, I estimate that Coles may give away up to 2.7 billion bags annually.

With each bag costing almost 3c, retailers stand to save more than A$170 million a year in direct costs. Selling these new bags at 15c each effectively creates another revenue stream potentially adding up to A$71 million in gross profit (6c x 1.18 billion units).

It might not actually reduce bags

In 2013, Target reverted back to providing free plastic bags after three years of charging 10c per bag. Other than hardware retailer Bunnings, no other large retailer has initiated a voluntary ban on single-use plastic bags.

Some Australian state and federal governments have been pushing for single-use plastic bag ban for almost 10 years. South Australia was the first to ban plastic bags from supermarkets in 2009, followed by the ACT in 2010, Northern Territory in 2011 and Tasmania in 2012.

In 2016 the Queensland Government released a discussion paper on the proposed ban. It is predicted all states will fall into line by mid-2018.

The past impact of applying a charge to the use of plastic bags has provided positive, but mixed results. In Australia, Bunnings reported an 80% reduction after implementing a charge for plastic bags, while a 2008 trial undertaken in three Victorian regional towns by Coles, Woolworths and IGA resulted in a 79% reduction.

In 2002, Ireland applied a 15 pence (22c) charge to single-use plastic bags, claiming a 90% reduction within 6 months (this was before the transition to the euro currency in the same year). Then in 2007 it increased the charge to 22 euro cents (32c) in response to increased bag usage. Sadly, shoppers had become conditioned to the 15p charge and returned to their old habits.

The UK government likewise reported an 85% reduction in single-use plastic bags in the first 6 months after a 5p charge (8c) was implemented in 2015. Similar results have been reported in the US, with a 94% reduction in Los Angeles County from the introduction of a charge for bags.

In the above cases (excluding Australian examples), single-use bags were still available, however a levy was applied, creating revenue for governments to channel back into environmental programs. This model is not the planned approach for Australia, were all single-use bags will be replaced with either the heavy duty (>35 micron, LDPE) option at 15c or the “green” polyethylene bag.

Charging for bags has minimal impact on the environment

Unfortunately, introducing a charge for bags doesn’t help the environment in isolation. While plastic bags represent only about 2% of landfill, there is certainly sufficient scientific evidence that plastic bags do present risks to marine life and clog waterways.

However, simply charging for a plastic bag, without directing these funds into environmental programs, does not necessarily resolve the problem. Shoppers slowly return to old habits, governments and retailers stop educating consumers and re-usable bags soon make their way into water ways and landfill.

Some shoppers simply forget to bring re-usable bags with them. The UK Department for Environment, Food and Rural Affairs found that the average UK household had 40 plastic bags stashed away around the home. Also a South Australian parliamentary review found that only about 30% of shoppers actually recycled their re-usable bags.

In the US, studies indicated 40% of shoppers continued to use disposable bags, despite a 5 cent levy.
Moving to a reusable option also doesn’t stop people discarding these new bags either. Another US study found many people still threw away reusable bags.

Ultimately, “banning the bag” is only the beginning. Retailers will need to remedy customer complaints as the phasing out of plastic bags begins.

The ConversationLike UK retailers, Australian supermarkets could choose to funnel some of the profits derived from the 15c reusable bag into community programs or environmental groups. Australian governments will also need fund ongoing education campaigns to draw attention to bans, alternatives and outcomes.

Gary Mortimer, Associate Professor, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

This South Pacific island of rubbish shows why we need to quit our plastic habit


Jennifer Lavers, University of Tasmania

A remote South Pacific island has the highest density of plastic debris reported anywhere on the planet, our new study has found. The Conversation

Our study, published in the journal Proceedings of the National Academy of Sciences, estimated that more than 17 tonnes of plastic debris has washed up on Henderson Island, with more than 3,570 new pieces of litter arriving every day on one beach alone.

Our study probably actually underestimates the extent of plastic pollution on Henderson Island, as we were only able to sample pieces bigger than two millimetres down to a depth of 10 centimetres. We also could not sample along cliffs.
Jennifer Lavers, Author provided

It is estimated that there are nearly 38 million pieces of plastic on the island, which is near the centre of the South Pacific Gyre ocean current.

Henderson Island, marked here by the red pin, is in the UK’s Pitcairn Islands territory and is more than 5,000 kilometres from the nearest major population centre. That shows plastic pollution ends up everywhere, even in the most remote parts of the world.
Google Maps

A 2014 paper published in the journal PLOS One used data from surface water all over the world. The researchers estimated that there are 5.25 trillion pieces of plastic in the top 10 centimetres of the world’s oceans.

Plastics pose a major threat to seabirds and other animals, and most don’t ever break down – they just break up. Every piece of petrochemical-derived plastic ever made still exists on the planet.

Jennifer Lavers, Research Scientist, Institute for Marine and Antarctic Studies, University of Tasmania

This article was originally published on The Conversation. Read the original article.