Plastic waste in the ocean is a global problem; some eight million metric tonnes of plastic ends up in the ocean every year.
One possible solution – paying a small amount for returned drink containers – has been consistently opposed by the beverage industry for many years. But for the first time our research, published in Marine Policy, has found that container deposits reduce the amount of beverage containers on the coasts of both the United States and Australia by 40%.
What’s more, the reduction is even more pronounced in areas of lower socio-economic status, where plastic waste is most common.
Plastic not so fantastic
There have been many suggestions for how to reduce marine debris. Some promote reducing plastic packaging, re-purposing plastic debris], or cleaning beaches. There has been a push to get rid of plastic straws, and even Queen Elizabeth II has banned single use plastics from Royal Estates! All of these contribute to the reduction of plastics, and are important options to consider.
Legislation and policy are another way to address the problems of plastic pollution. Recent legislation includes plastic bag bans and microbead bans. Economic incentives, such as container deposits, have attracted substantial attention in countries around the world.
Several Australian jusrisdictions, including South Australia, the Northern Territory, and New South Wales), already have container deposit laws, with Western Australia and Queensland set to start in 2019. In the United States, 10 states have implemented container deposit schemes.
But how effective is a cash for containers program? While there is evidence to suggest that container deposits increase return rates and decrease litter, until now there has been no study asking whether they also reduce the sources of debris entering the oceans.
In Australia, we analysed data from litter surveys by Keep South Australia Beautiful, and Keep Australia Beautiful. In the US, we accessed data from the Ocean Conservancy’s International Coastal Cleanup.
We compared coastline surveys in states with a container deposit scheme to those without. In both Australia and the US, the proportion of beverage containers in states without a deposit scheme was about 1.6 times higher than their neighbours. Based on estimates of debris loading on US beaches that we conducted previously, if all coastal states in the United States implemented deposit schemes, there would be 6.6 million fewer containers on the shoreline each year.
Keep your lid on
But how do we know that this difference is caused by the deposit scheme? Maybe people in states with container deposit schemes simply drink fewer bottled beverages than people states without them, and so there are fewer containers in the litter stream?
To answer that question, we measured the ratio of lids to containers from the same surveys. Lids are manufactured in equal proportion to containers, and arrive to the consumer on the containers, but do not attract a deposit in either country.
If deposit schemes cause a decrease in containers in the environment, it is unlikely to cause a similar decrease in littered lids. So, if a cashback incentive is responsible for the significantly lower containers on the shorelines, we would expect to see a higher ratio of lids to containers in states with these programs, as compared to states without.
That’s exactly what we found.
We were also interested in whether other factors also influenced the amount of containers in the environment. We tested whether the socio-economic status of the area (as defined by data from the Australian census) was related to more containers in the environment. Generally, we found fewer containers in the environment in wealthier communities. However, the presence of a container deposit reduced the container load more in poorer communities.
This is possibly because a relatively small reward of 10 cents per bottle may make a bigger difference to less affluent people than to more wealthy consumers. This pattern is very positive, as it means that cashback programs have a stronger impact in areas of lower economic advantage, which are also the places with the biggest litter problems.
Ultimately, our best hope of addressing the plastic pollution problem will be through a range of approaches. These will include bottom-up grassroots governance, state and federal legislation, and both hard and soft law.
Along with these strategies, we must see a shift in the type of we products use and their design. Both consumers and manufacturers are responsibility for shifting from a make, use, dispose culture to a make, reuse, repurpose, and recycle culture, also known as a circular economy.
Qamar Schuyler, Research Scientist, Oceans and Atmospheres, CSIRO; Britta Denise Hardesty, Principal Research Scientist, Oceans and Atmosphere Flagship, CSIRO, and Chris Wilcox, Senior Research Scientist, CSIRO
Shopping can be confusing at the best of times, and trying to find environmentally friendly options makes it even more difficult. Welcome to our Sustainable Shopping series, in which we ask experts to provide easy eco-friendly guides to purchases big and small. Send us your suggestions for future articles here.
Scientists often get a bad rap as party poopers. As a case in point, my colleagues and I have provided data on the impacts of balloon releases on marine wildlife.
So when glitter – a highly visible and easily obtained microplastic – comes under the microscope, you might be tempted to groan. The good news is that we’re not out to ruin the fun: with Mardi Gras around the corner (bringing a ubiquity of sparkling Instagrams), here’s how to find ecologically friendly glitter.
All glitter goes to the ocean
When something fun or common is revealed to be destructive it should be a point of pride in our society that we adjust, adapt and move on to safer alternatives.
It therefore makes sense to investigate what data exist for glitter, and to consider whether it’s time for a change in attitude. So, what is glitter?
Glitter is typically made from polyethylene, the same plastic found in plastic bags and a host of other products. Despite glitter’s popularity in everything from cosmetics and toothpaste to crafts and clothes, remarkably little is known about the distribution or impacts of glitter on our environment. As a scientist, that worries me. Glitter is incorporated into consumer products without any real knowledge of its safety.
In contrast, there are dozens of scientific papers on micro-bead scrubbers (tiny plastic beads), which originate from many of the same products (such as cosmetics and toothpaste).
Research on micro-beads suggests that around 8 trillion beads are released into aquatic habitats every day in the United States alone.
Data for glitter are not available, but given its widespread use the situation is likely to be similarly alarming. It’s far too small for waste treatment facilities to capture, so glitter goes straight into your local river and out into the ocean. Because glitter particles are typically 1 millimetre in size or smaller, they can be ingested by a range of creatures, including mussels.
Again, data on micro-beads can tell us why we should be worried about this: a recent study from Australia showed that toxic chemicals associated with micro-beads can “leach” into the tissues of marine creatures, contaminating their bodies. If mussels, fish and other animals are ingesting glitter and micro-beads, these contaminants likely also pose a risk to humans that consume them.
Thankfully, science is here to help. A range of compostable, vegan, 100% plastic-free “bio-glitters” have been created and are readily available online. So, at your next event, you can celebrate in glorious, sparkly style while also educating passers-by about ocean conservation. (I assure you, this is very popular; I do it all the time and I’m the life of the party.)
What to look for
Mica, a naturally occurring sparkling mineral, is often offered as a non-plastic alternative to glitter. However, some brands, such as Lush, are now using “synthetic mica” (made in a lab) because mica mining has been associated with child labour, especially in India.
Some plastics labelled “bio-degradable” will only break down in industrial composting units, at temperatures over 50℃. This is very unlikely to happen in the ocean, so look for terms like “compostable” and “organic” instead. (For more information on the difference between bio-degradable, compostable and everything in between, this United Nations report is very comprehensive – just read the summary if you’re in a hurry).
Fortunately, eco-friendly glitter is becoming much easier to find around the world, and more suppliers are turning to cellulose and other plant-derived bases for their product. Wild Glitter‘s founder, like many in the industry, cites “watching a weekend’s worth of plastic glitter wash down the plughole after a festival” as the impetus to sell an “ethical, eco-friendly, cruelty-free way to sparkle”.
Eco Glitter Fun is a member of the Plastics Ocean Foundation, a global non-profit; Glo Tatts makes beautiful temporary glitter tattoos; and, for an Australian twist, Eco Glitter make their product from Eucalyptus cellulose.
Bio-glitter can be incorporated into any product. Tasmanian soap maker Veronica Foale switched to bio-glitter last year and hasn’t looked back – if a small business in a rural area can do it, you can too!
This is the key to success in the battle against litter: not all changes are difficult and affordable alternatives do exist. Once you’ve mastered bio-glitter, embrace the next challenge – a bamboo toothbrush perhaps, or reusable Onya produce bags? Never stop learning. Go forth and sparkle responsibly.
There are more than 11 billion pieces of plastic debris on coral reefs across the Asia-Pacific, according to our new research, which also found that contact with plastic can make corals more than 20 times more susceptible to disease.
In our study, published today in Science, we examined more than 124,000 reef-building corals and found that 89% of corals with trapped plastic had visual signs of disease – a marked increase from the 4% chance of a coral having disease without plastic.
Globally, more than 275 million people live within 30km of coral reefs, relying on them for food, coastal protection, tourism income, and cultural value.
With coral reefs already under pressure from climate change and mass bleaching events, our findings reveal another significant threat to the world’s corals and the ecosystems and livelihoods they support.
In collaboration with numerous experts and underwater surveyors across Indonesia, Myanmar, Thailand and Australia, we collected data from 159 coral reefs between 2010 and 2014. In so doing, we collected one of the most extensive datasets of coral health in this region and plastic waste levels on coral reefs globally.
Our research provides one of the most comprehensive estimates of plastic waste on the seafloor, and its impact on one of the world’s most important ecosystems.
The number of plastic items entangled on the reefs varied immensely among the different regions we surveyed – with the lowest levels found in Australia and the highest in Indonesia.
An estimated 80% of marine plastic debris originates from land. The variation of plastic we observed on reefs during our surveys corresponded to the estimated levels of plastic litter entering the ocean from the nearest coast. One-third of the reefs we surveyed had no derelict plastic waste, however others had up 26 pieces of plastic debris per 100 square metres.
We estimate that there are roughly 11.1 billion plastic items on coral reefs across the Asia-Pacific. What’s more, we forecast that this will increase 40% in the next seven years – equating to an estimated 15.7 billion plastic items by 2025.
This increase is set to happen much faster in developing countries than industrialised ones. According to our projections, between 2010 and 2025 the amount of plastic debris on Australian coral reefs will increase by only about 1%, whereas for Myanmar it will almost double.
How can plastic waste cause disease?
Although the mechanisms are not yet clear, the influence of plastic debris on disease development may differ among the three main global diseases we observed to increase when plastic was present.
Plastic debris can open wounds in coral tissues, potentially letting in pathogens such as Halofolliculina corallasia, the microbe that causes skeletal eroding band disease.
Plastic debris could also introduce pathogens directly. Polyvinyl chloride (PVC) – a very common plastic used in children’s toys, building materials like pipes, and many other products – have been found carrying a family of bacteria called Rhodobacterales, which are associated with a suite of coral diseases.
Similarly, polypropylene – which is used to make bottle caps and toothbrushes – can be colonised by Vibrio, a potential pathogen linked to a globally devastating group of coral diseases known as white syndromes.
Finally, plastic debris overtopping corals can block out light and create low-oxygen conditions that favour the growth of microorganisms linked to black band disease.
Structurally complex corals are eight times more likely to be affected by plastic, particularly branching and tabular species. This has potentially dire implications for the numerous marine species that shelter under or within these corals, and in turn the fisheries that depend on them.
Our study shows that reducing the amount of plastic debris entering the ocean can directly prevent disease and death among corals.
Once corals are already infected, it is logistically difficult to treat the resulting diseases. By far the easiest way to tackle the problem is by reducing the amount of mismanaged plastic on land that finds its way into the ocean.
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.
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.
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?
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.
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.
There 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.
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.
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.
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.
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.
There 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.