Japan plans to dump a million tonnes of radioactive water into the Pacific. But Australia has nuclear waste problems, too


Tilman Ruff, University of Melbourne and Margaret Beavis

The Japanese government recently announced plans to release into the sea more than 1 million tonnes of radioactive water from the severely damaged Fukushima Daiichi nuclear plant.

The move has sparked global outrage, including from UN Special Rapporteur Baskut Tuncak who recently wrote,

I urge the Japanese government to think twice about its legacy: as a true champion of human rights and the environment, or not.

Alongside our Nobel Peace Prize-winning work promoting nuclear disarmament, we have worked for decades to minimise the health harms of nuclear technology, including site visits to Fukushima since 2011. We’ve concluded Japan’s plan is unsafe, and not based on evidence.

Japan isn’t the only country with a nuclear waste problem. The Australian government wants to send nuclear waste to a site in regional South Australia — a risky plan that has been widely criticised.

Contaminated water in leaking tanks

In 2011, a massive earthquake and tsunami resulted in the meltdown of four large nuclear reactors, and extensive damage to the reactor containment structures and the buildings which house them.

Water must be poured on top of the damaged reactors to keep them cool, but in the process, it becomes highly contaminated. Every day, 170 tonnes of highly contaminated water are added to storage on site.

As of last month, this totalled 1.23 million tonnes. Currently, this water is stored in more than 1,000 tanks, many hastily and poorly constructed, with a history of leaks.

How does radiation harm marine life?

If radioactive material leaks into the sea, ocean currents can disperse it widely. The radioactivity from Fukushima has already caused widespread contamination of fish caught off the coast, and was even detected in tuna caught off California.




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Four things you didn’t know about nuclear waste


Ionising radiation harms all organisms, causing genetic damage, developmental abnormalities, tumours and reduced fertility and fitness. For tens of kilometres along the coast from the damaged nuclear plant, the diversity and number of organisms have been depleted.

Of particular concern are long-lived radioisotopes (unstable chemical elements) and those which concentrate up the food chain, such as cesium-137 and strontium-90. This can lead to fish being thousands of times more radioactive than the water they swim in.

Failing attempts to de-contaminate the water

In recent years, a water purification system — known as advanced liquid processing — has been used to treat the contaminated water accumulating in Fukushima to try to reduce the 62 most important contaminating radioisotopes.

But it hasn’t been very effective. To date, 72% of the treated water exceeds the regulatory standards. Some treated water has been shown to be almost 20,000 times higher than what’s allowed.




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The cherry trees of Fukushima


One important radioisotope not removed in this process is tritium — a radioactive form of hydrogen with a half-life of 12.3 years. This means it takes 12.3 years for half of the radioisotope to decay.

Tritium is a carcinogenic byproduct of nuclear reactors and reprocessing plants, and is routinely released both into the water and air.

The Japanese government and the reactor operator plan to meet regulatory limits for tritium by diluting contaminated water. But this does not reduce the overall amount of radioactivity released into the environment.

How should the water be stored?

The Japanese Citizens Commission for Nuclear Energy is an independent organisation of engineers and researchers. It says once water is treated to reduce all significant isotopes other than tritium, it should be stored in 10,000-tonne tanks on land.

If the water was stored for 120 years, tritium levels would decay to less than 1,000th of the starting amount, and levels of other radioisotopes would also reduce. This is a relatively short and manageable period of time, in terms of nuclear waste.

Then, the water could be safely released into the ocean.

Nuclear waste storage in Australia

Australians currently face our own nuclear waste problems, stemming from our nuclear reactors and rapidly expanding nuclear medicine export business, which produces radioisotopes for medical diagnosis, some treatments, scientific and industrial purposes.




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This is what happens at our national nuclear facility at Lucas Heights in Sydney. The vast majority of Australia’s nuclear waste is stored on-site in a dedicated facility, managed by those with the best expertise, and monitored 24/7 by the Australian Federal Police.

But the Australian government plans to change this. It wants to transport and temporarily store nuclear waste at a facility at Kimba, in regional South Australia, for an indeterminate period. We believe the Kimba plan involves unnecessary multiple handling, and shifts the nuclear waste problem onto future generations.

The proposed storage facilities in Kimba are less safe than disposal, and this plan is well below world’s best practice.

The infrastructure, staff and expertise to manage and monitor radioactive materials in Lucas Heights were developed over decades, with all the resources and emergency services of Australia’s largest city. These capacities cannot be quickly or easily replicated in the remote rural location of Kimba. What’s more, transporting the waste raises the risk of theft and accident.

And in recent months, the CEO of regulator ARPANSA told a senate inquiry there is capacity to store nuclear waste at Lucas Heights for several more decades. This means there’s ample time to properly plan final disposal of the waste.

The legislation before the Senate will deny interested parties the right to judicial review. The plan also disregards unanimous opposition by Barngarla Traditional Owners.




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The Conversation contacted Resources Minister Keith Pitt who insisted the Kimba site will consolidate waste from more than 100 places into a “safe, purpose-built, state-of-the-art facility”. He said a separate, permanent disposal facility will be established for intermediate level waste in a few decades’ time.

Pitt said the government continues to seek involvement of Traditional Owners. He also said the Kimba community voted in favour of the plan. However, the voting process was criticised on a number of grounds, including that it excluded landowners living relatively close to the site, and entirely excluded Barngarla people.

Kicking the can down the road

Both Australia and Japan should look to nations such as Finland, which deals with nuclear waste more responsibly and has studied potential sites for decades. It plans to spend 3.5 billion euros (A$5.8 billion) on a deep geological disposal site.




Read more:
Risks, ethics and consent: Australia shouldn’t become the world’s nuclear wasteland


Intermediate level nuclear waste like that planned to be moved to Kimba contains extremely hazardous materials that must be strictly isolated from people and the environment for at least 10,000 years.

We should take the time needed for an open, inclusive and evidence-based planning process, rather than a quick fix that avoidably contaminates our shared environment and creates more problems than it solves.

It only kicks the can down the road for future generations, and does not constitute responsible radioactive waste management.


The following are additional comments provided by Resources Minister Keith Pitt in response to issues raised in this article (comments added after publication):

(The Kimba plan) will consolidate waste into a single, safe, purpose-built, state-of-the-art facility. It is international best practice and good common sense to do this.

Key indicators which showed the broad community support in Kimba included 62 per cent support in the local community ballot, and 100 per cent support from direct neighbours to the proposed site.

In assessing community support, the government also considered submissions received from across the country and the results of Barngarla Determination Aboriginal Corporation’s own vote.

The vast majority of Australia’s radioactive waste stream is associated with nuclear medicine production that, on average, two in three Australians will benefit from during their lifetime.

The facility will create a new, safe industry for the Kimba community, including 45 jobs in security, operations, administration and environmental monitoring.The Conversation

Tilman Ruff, Associate Professor, Education and Learning Unit, Nossal Institute for Global Health, School of Population and Global Health, University of Melbourne and Margaret Beavis, Tutor Principles of Clinical Practice Melbourne Medical School

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Apple’s iPhone 12 comes without a charger: a smart waste-reduction move, or clever cash grab?



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Michael Cowling, CQUniversity Australia and Ritesh Chugh, CQUniversity Australia

Apple has released its new smartphone, the iPhone 12, without an accompanying charger or earbuds. Users have harshly criticised the company for this move and will have to purchase these accessories separately, if needed.

While some see it as cost-cutting, or a way for Apple to profit further by forcing customers to buy the products separately, the technology giant said the goal was to reduce its carbon footprint.

This is the first time a major smartphone manufacturer has released a mobile without a charger. Earlier this year, reports emerged of Samsung considering a similar move, but it has yet to follow through.

But even if abandoning chargers is a way for Apple to save money, the action could have a significant, positive impact on the environment.

Australians, on average, buy a new mobile phone every 18-24 months. In Australia, there are about 23 million phones sitting unused — and therefore likely a similar number of accompanying chargers.

Just as single-use shopping bags contribute to plastic waste, unused and discarded electronic appliances contribute to electronic waste (e-waste).




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Don’t chuck that old mobile phone, there’s gold in there


You can reuse a shopping bag, so why not your phone charger?

Just over a decade ago, Australia started to ban single-use plastic bags, starting with South Australia. Today, every state and territory in Australia has enforced the ban except New South Wales — which intends to do so by the end of 2021.

Since South Australia implemented its ban in 2008, state government estimates suggest it has avoided 8,000kg of marine litter each year — and abated more than 4,000 tonnes of greenhouse gas emissions.

The benefits for the environment have been clear. So, why are we so hesitant to do the same for e-waste?

E-waste is a real, but fixable, environmental issue

E-waste includes different forms of discarded electric and electronic appliances that are no longer of value to their owners. This can include mobile phones, televisions, computers, chargers, keyboards, printers and earphones.

Currently there are about 4.78 billion mobile phone users globally (61.2% of the world’s population). And mobile phone chargers alone generate more than 51,000 tonnes of e-waste per year.

On this basis, the environment would greatly benefit if more users reused phone chargers and if tech companies encouraged a shift to standardised charging that works across different mobile phone brands.

This would eventually lead to a reduction in the manufacturing of chargers and, potentially, less exploitation of natural resources.

Who needs a charger with an Apple logo anyway?

Citing an increase in e-waste and consumer frustration with multiple chargers, the European Parliament has been pushing for standardised chargers for mobile phones, tablets, e-book readers, smart cameras, wearable electronics and other small or medium-sized electronic devices.

This would negate the need for users to buy different chargers for various devices.

Electronics 'sprout' from the ground.
Digital consumption is on the rise and unlikely to slow down any time soon. Recycling is one option, but how else can tech companies innovate to reduce environmental harm?
Shutterstock

Of course, there’s no doubt phone companies want people to regularly buy new phones. Apple themselves have been accused of building a feature into phones that slows them down as they get older. Apple responded by saying this was simply to keep devices running as their batteries became worn down.

But even if this is the case, Apple’s decision to ship phones without chargers would still reduce the use of precious materials. A smaller product box would let Apple fit up to 70% more products onto shipping pallets — reducing carbon emissions from shipping.

However, it remains to be seen exactly how much this would assist in Apple’s environmental goals, especially if many consumers end up buying a charger separately anyway.

Apple equates its recent “climate conscious” changes to the iPhone 12 with removing 450,000 cars from the road annually. The company has a target of becoming carbon-neutral by 2030.

Are wireless chargers the answer?

It’s worth considering whether Apple’s main incentive is simply to cut costs, or perhaps push people towards its own wireless charging devices.

These concerns are not without merit. Apple is one of the richest companies in the world, with most of its market capital made with hardware sales.

Without a shift to a standardised plug-in charger, a wireless charging boom could be an environmental disaster (even though it’s perhaps inevitable due to its convenience). Wireless charging consumes around 47% more power than a regular cable.

This may be a concern, as the sustainability advantages of not including a charger could come alongside increased energy consumption. Currently, the Information, Communication and Technology (ICT) sector is responsible for about 2% of the world’s energy consumption.

Unused electronic devices in a pile.
How many unused devices do you have lying around the house?
Shutterstock

The case for a universal plug-in charger

Perhaps one solution to the dilemma is device trade-in services, which many companies already offer, including Apple and Samsung.

Apple gives customers a discount on a new device if they trade in their older model, instead of throwing it out. Similar services are offered by third parties such as Optus, Telstra, MobileMonster and Boomerang Buy Back.

Ultimately, however, the best solution would be for tech giants to agree on a universal plug-in charger for all small or medium-sized electronic devices, including mobile phones.

And hopefully, just as we all now take reusable bags to the grocer with us, in a few years we’ll be able to use a common charger for all our devices — and we’ll wonder what all the fuss was about.




Read more:
Apple releases fast 5G iPhones, but not for Australia. And we’re lagging behind in getting there


The Conversation


Michael Cowling, Associate Professor – Information & Communication Technology (ICT), CQUniversity Australia and Ritesh Chugh, Senior Lecturer/Discipline Lead – Information Systems and Analysis, CQUniversity Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Millions of face masks are being thrown away during COVID-19. Here’s how to choose the best one for the planet



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Mayuri Wijayasundara, Deakin University

Face masks are part of our daily lives during the pandemic. Many are made from plastics and designed to be used just once, which means thousands of tonnes of extra waste going to landfill.

Masks may help stop the spread of the coronavirus. But according to one estimate, if everyone in the United Kingdom used a single-use mask each day for a year, it would create 66,000 tonnes of contaminated waste and 57,000 tonnes of plastic packaging.

Evidence also suggests masks may be a source of harmful microplastic fibres on land and in waterways and litter.

So let’s look at how face masks might be designed to cause minimal harm to the environment, while still doing their job – and which type is best for you.

A woman holding and wearing an N95 mask
N95 masks are used in hospital settings.
Shutterstock

Circular thinking

China is the world’s biggest face mask manufacturer. Its daily output of face masks reportedly reached 116 million units in February this year. That creates a big waste management problem around the world.

One way to address this is to adopt “circular design” principles. This thinking seeks to reduce waste and pollution through product design, keep products and materials in use, and regenerate natural systems.




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Which face mask should I wear?


When it comes to face masks, the three common types are cloth, surgical and N-95. N-95 masks offer the highest level of protection, blocking about 95% of airborne particles. Cloth masks are designed to be used more than once, while surgical and N-95 masks are usually intended for single use.

Face masks may consist of one or more layers, each with different functions:

  • an outermost layer, designed to repel liquids such as water
  • the innermost layer, which absorbs moisture and allows comfort and breathability
  • a non-absorbent middle layer, to filter particles.
Two people watching a sports match wearing masks
Surgical masks are generally intended as single-use items.
BrendanThorne/AAP

Each type of mask is made of different materials and used in varying settings:

– N-95 masks: These are designed to protect the wearer from 95% of airborne particles and are largely worn by health workers. N-95 masks are designed to fit closely to the face and are usually worn only once. N-95 masks comprise:

  • a strap (polyisoprene)
  • staples (steel)
  • nose foam (polyurethane)
  • nose clip (aluminum)
  • filter (polypropylene)
  • valve diaphragm (polyisoprene).

– Surgical masks: These are designed to protect sterile environments from the wearer, acting as barrier to droplets or aerosols. Generally intended as single-use items, they comprise mostly polypropylene between two layers of non-woven fabric.

– Cloth masks: These types of masks are worn by the general public. Some are homemade from fabric scraps or old clothing. They may be wholly reusable, or partially reusable with replaceable filters that must be disposed of.

These masks typically comprise an outer layer of polyester or polypropylene (or in some cases, cotton), and an inner layer designed for breathability and comfort – usually cotton or a cotton-polyester blend.

Research suggests cloth masks are less effective at filtering particles than medical masks, but may may give some protection if well-fitted and properly designed. Health advice is available to help guide their use.

Cloth masks
Many cloth masks are handmade, and can be reused.
Shutterstock

Designing for a healthier environment

It’s important to note that any attempt to redesign face masks must ensure they offer adequate protection to the wearer. Where masks are used in a medical setting, design changes must also meet official standards such as barrier efficiency, breathing capacity and fire resistance.

With this in mind, reducing the environmental harm caused by masks could be done in several ways:

– Design with more reusable parts

Evidence suggests reusable cloth masks perform almost as well as single-use masks, but without the associated waste. One life cycle assessment conducted in the UK found masks that could be washed and reused were the best option for the environment. Reusable masks with replaceable filters were the second-best option.

The study also found having a higher number of masks in rotation to allow for machine washing was better for the environment than manual washing.

– Make masks easier to dispose of or recyle

In high-risk settings such as hospitals and clinics, the reuse of masks may not be possible or desirable, meaning they must be disposed of. In medical settings, there are systems in place for disposal of such protective gear, which usually involves segregation and incineration.

But the general public must dispose of masks themselves. Because masks usually comprise different materials, this can be complicated. For example, recovering the components of a N-95 mask for recycling would involve putting the straps, nose foam, filter and valve in one bin and the metal staples and nose clip in another. And some recyclers may see mask recycling as a health risk. These difficulties mean masks often end up in landfill.

Masks would be easier to recycle if the were made of fewer materials and were easy to disassemble.

– Use biodegradable materials

For single-use items, placing synthetics with biodegradable materials would be a first step in circular design thinking.

The abaca plant, a relative of the banana tree, offers one potential option. Its leaf fibre reportedly repels water better than traditional face masks, is as strong as polymer and decomposes within two months. Most abaca is currently produced in the Philippines.

Face mask on the ground in front of bins
Recycling of face masks can be complicated.
Shutterstock

Which mask should you choose?

From a purely environmental perspective, research suggests owning multiple reusable face masks, and machine-washing them together, is the best option. Using filters with reusable face masks is a second-best option.

But when choosing a mask, consider where you will wear it. Unless cloth masks are shown to be as effective as other masks, health-care workers should not use them. But they may be suitable in low-risk everyday settings.

In the longer term, governments and manufacturers must make every effort to design masks that will not harm the planet – and consumers should demand this. Face masks will probably be ubiquitous on our streets for months to come. But once the pandemic is over, the environmental legacy may last for decades, if not centuries.




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Cloth masks do protect the wearer – breathing in less coronavirus means you get less sick


The Conversation


Mayuri Wijayasundara, Lecturer, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We estimate there are up to 14 million tonnes of microplastics on the seafloor. It’s worse than we thought



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Britta Denise Hardesty, CSIRO; Chris Wilcox, CSIRO, and Justine Barrett, CSIRO

Nowhere, it seems, is immune from plastic pollution: plastic has been reported in the high Arctic oceans, in the sea ice around Antarctica and even in the world’s deepest waters of the Mariana Trench.

But just how bad is the problem? Our new research provides the first global estimate of microplastics on the seafloor — our research suggests there’s a staggering 8-14 million tonnes of it.

This is up to 35 times more than the estimated weight of plastic pollution on the ocean’s surface.

What’s more, plastic production and pollution is expected to increase in coming years, despite increased media, government and scientific attention on how plastic pollution can harm marine ecosystems, wildlife and human health.

These findings are yet another wake-up call. When the plastic we use in our daily lives reaches even the deepest oceans, it’s more urgent than ever to find ways to clean up our mess before it reaches the ocean, or to stop making so much of it in the first place.

Breaking down larger plastic

Our estimate of microplastics on the seafloor is huge, but it’s still a fraction of the amount of plastic dumped into the ocean. Between 4-8 million tonnes of plastic are thought to enter the sea each and every year.




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Eight million tonnes of plastic are going into the ocean each year


Most of the plastic dumped into the ocean likely ends up on the coasts, not floating around the ocean’s surface or on the seafloor. In fact, three-quarters of the rubbish found along Australia’s coastlines is plastics.

A dead albatross with plastic in its stomach from Midway Atoll
Plastic including toothbrushes, cigarette lighters, bottle caps and other hard plastic fragments are found in the stomachs of many marine species.
Britta Denise Hardesty

The larger pieces of plastic that stay in the ocean can deteriorate and break down from weathering and mechanical forces, such as ocean waves. Eventually, this material turns into microplastics, pieces smaller than 5 millimetres in diameter.

Their tiny size means they can be eaten by a variety of marine wildlife, from plankton to crustaceans and fish. And when microplastics enter the marine food web at low levels, it can move up the food chain as bigger species eat smaller ones.

But the problem isn’t as well documented for microplastics on the seafloor. While plastics, including microplastics, have been found in deep-sea sediments in all ocean basins across the world, samples have been small and scarce. This is where our research comes in.

Collecting samples in the Great Australian Bight

We collected samples using a robotic submarine in a range of sea depths, from 1,655 to 3,062 metres, in the Great Australian Bight, up to 380 kilometres offshore from South Australia. The submarine scooped up 51 samples of sand and sediment from the seafloor and we analysed them in a laboratory.

Sampling of deep sea sediments took place using an underwater robot.
CSIRO, Author provided

We dried the sediment samples, and found between zero and 13.6 plastic particles per gram. This is up to 25 times more microplastics than previous deep-sea studies. And it’s much higher than studies in other regions, including in the Arctic and Indian Oceans.

While our study looked at one general area, we can scale up to calculate a global estimate of microplastics on the seafloor.

Using the estimated size of the entire ocean — 361,132,000 square kilometres — and the average number and size of particles in our sediment samples, we determined the total, global weight as between 8.4 and 14.4 million tonnes. This range takes into account the possible weights of individual microplastics.

How did the plastic get there?

It’s important to note that since our location was remote, far from any urban population centre, this is a conservative estimate. Yet, we were surprised at just how high the microplastic loads were there.

Plastic waste floating in the ocean
Areas with floating rubbish on the ocean’s surface have plastic on the seafloor.
Shutterstock

Few studies have conclusively identified how microplastics travel to their ultimate fate.

Larger pieces of plastic that get broken down to smaller pieces can sink to the seafloor, and ocean currents and the natural movement of sediment along continental shelves can transport them widely.

But not all plastic sinks. A 2016 study suggests interaction with marine organisms is another possible transport method.

Scientists in the US have shown microbial communities, such as bacteria, can inhabit this marine “plastisphere” — a term for the ecosystems that live in plastic environments. The microbes weigh the plastic down so it no longer floats. We also know mussels and other invertebrates may colonise floating plastics, adding weight to make them sink.




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The type of rubbish will also determine whether it gets washed up on the beach or sinks to the seafloor.

For example, in a previous study we found cigarette butts, plastic fragments, bottlecaps and food wrappers are common on land, though rare on the seabed. Meanwhile, we found entangling items such fishing line, ropes and plastic bags are common on the seafloor.

Microplastics at the water's edge
We were surprised at just how high the microplastic loads were in such a remote location.
CSIRO

Interestingly, in our new study we also found the number of plastic fragments on the seafloor was generally higher in areas where there was floating rubbish on the ocean’s surface. This suggests surface “hotspots” may be reflected below.

It’s not clear why just yet, but it could be because of the geology and physical features of the seabed, or because local currents, winds and waves result in accumulating zones on the ocean’s surface and the seabed nearby.

Stop using so much plastic

Knowing how much plastic sinks to the ocean floor is an important addition to our understanding of the plastic pollution crisis. But stemming the rising tide of plastic pollution starts with individuals, communities and governments – we all have a role to play.

Reusing, refusing and recycling are good places to start. Seek alternatives and support programs, such as Clean Up Australia Day, to stop plastic waste from entering our environment in the first place, ensuring it doesn’t then become embedded in our precious oceans.




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The oceans are full of our plastic – here’s what we can do about it


The Conversation


Britta Denise Hardesty, Principal Research Scientist, Oceans and Atmosphere Flagship, CSIRO; Chris Wilcox, Senior Principal Research Scientist, CSIRO, and Justine Barrett, Research assistant, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

New Zealand invests in growing its domestic recycling industry to create jobs and dump less rubbish at landfills



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Jeff Seadon, Auckland University of Technology

New Zealand’s government recently put more than NZ$160 million towards developing a domestic recycling sector to create jobs as part of its economic recovery from the COVID-19 pandemic.

New Zealanders recycle 1.3 million tonnes of materials each year, but 70% is currently exported. A recent NZ$36.7 million funding boost to upgrade recycling plants throughout the country followed a NZ$124 million injection into recycling infrastructure to grow processing capacity onshore. The investment signals a focus on supporting services that create employment and increase efficiency or reduce waste.

The potential for expansion in onshore processing of recyclable waste is enormous – and it could lead to 3.1 million tonnes of waste being diverted from landfills. But it will only work if it is part of a strategy with clear and measurable targets.

COVID-19 impacts

During New Zealand’s level 4 lockdown between March and May, general rubbish collection was classed as an essential service and continued to operate. But recycling was sporadic.

Whether or not recycling services continued depended on storage space and the ability to separate recyclables under lockdown conditions. Facilities that relied on manual sorting could not meet those requirements and their recycling was sent to landfill. Only recycling plants with automated sorting could operate.

New Zealand’s reliance on international markets showed a lack of resilience in the waste management system. Any changes in international prices were duplicated in New Zealand and while exports could continue under tighter border controls, it was no longer economically viable to do so for certain recyclable materials.

International cardboard and paper markets collapsed and operators without sufficient storage space sent materials to landfill. Most plastics became uneconomic to recycle.

Recycling and rubbish bins
New Zealanders recycle 1.3 million tonnes each year.
Shutterstock/Josie Garner

In contrast, for materials processed in New Zealand — including glass, metals and some plastics — recycling remains viable. Many local authorities are now limiting their plastic collections to those types that have expanding onshore processing capacity.

Soft packaging plastics are also being collected again, but only in some places and in smaller quantities than at the height of the soft plastics recycling scheme, to be turned into fence posts and other farm materials.




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What happens to the plastic you recycle? Researchers lift the lid


The investment in onshore processing facilities is part of a move towards a circular economy. The government provided the capital for plants to recycle PET plastics, used to make most drink bottles and food trays. PET plastics can be reprocessed several times.

This means items such as meat trays previously made from polystyrene, which is not recyclable from households, could be made from fully recyclable PET. Some of the most recent funding goes towards providing automatic optical sorters to allow recycling plants to keep operating under lockdown conditions.

Regulation changes

The government also announced an expansion of the landfill levy to cover more types of landfills and for those that accept household wastea progressive increase from NZ$10 to NZ$60 per tonne of waste.

This will provide more money for the Waste Minimisation Fund, which in turn funds projects that lead to more onshore processing and jobs.

Last year’s ban on single-use plastic bags took more than a billion bags out of circulation, which represents about 180 tonnes of plastic that is not landfilled. But this is a small portion of the 3.7 million tonnes of waste that go to landfill each year.

More substantial diversion schemes include mandatory product stewardship schemes currently being implemented for tyres, electrical and electronic products, agrichemicals and their containers, refrigerants and other synthetic greenhouse gases, farm plastics and packaging.

An example of the potential gains for product stewardship schemes is e-waste. Currently New Zealand produces about 80,000 tonnes of e-waste per year, but recycles only about 2% (1,600 tonnes), most of which goes offshore for processing. Under the scheme, e-waste will be brought to collection depots and more will be processed onshore.

Landfilling New Zealand’s total annual e-waste provides about 50 jobs. Recycling it could create 200 jobs and reusing it is estimated to provide work for 6,400 people.




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Waste not, want not: Morrison government’s $1b recycling plan must include avoiding waste in the first place


But all these initiatives are not enough. We need a coordinated strategy with clear targets.

The current Waste Strategy has only two goals: to reduce the harmful effects of waste and improve resource use efficiency. Such vague goals have resulted in a 37% increase in waste disposal to landfill in the last decade.

An earlier 2002 strategy achieved significantly better progress. The challenge is clear. A government strategy with measurable targets for waste diversion from landfill can lead us to better resource use and more jobs.The Conversation

Jeff Seadon, Senior Lecturer, Auckland University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We composted ‘biodegradable’ balloons. Here’s what we found after 16 weeks



‘Biodegradable’ balloons after 16 weeks in freshwater.
Jesse Benjamin, Author provided

Morgan Gilmour, University of Tasmania and Jennifer Lavers, University of Tasmania

After 16 weeks in an industrial compost heap, we unearthed blue and white balloons and found them totally unscathed. The knots we spent hours painstakingly tying by hand more than four months ago were still attached, and sparkly blue balloons still glinted in the sun.

These balloons originally came from packages that advertised them as “100% biodegradable”, with the manufacturers assuring they were made of “100% natural latex rubber”. The implication is that these balloons would have no trouble breaking down in the environment.




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Balloon releases have deadly consequences – we’re helping citizen scientists map them


This appeals to eco-conscious consumers, but really just fuels corporate greenwashing — unsubstantiated claims of environmentally friendly and safe products.

Holding perfectly intact balloons in our hands after four months in industrial compost, we had cause to question these claims, and ran experiments.

What’s the problem?

This problem is two-fold. First, balloons are additional plastic waste in the environment. They are lightweight and can travel on air currents far from the point of release. For example, one 2005 study found a balloon travelled more than 200 kilometres.

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Not much changed after 14 weeks.
Morgan Gilmour, Author provided

When they pop, they float back to the earth’s surface and land in, for example, the ocean or the desert, and wash up on beaches where animals can eat them, from sea turtles and seabirds to desert tortoises.

The stretchiness of balloons means they can get stuck in animals’ digestive tracts, which will cause choking, blockage, decreased nutrient absorption and effectively starve the animal.




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How to get abandoned, lost and discarded ‘ghost’ fishing gear out of the ocean


Second, what most consumers don’t realise, is that to shape milky natural rubber latex sap into the product we know as a balloon, many additional chemicals need to be added to the latex.

These chemicals include antioxidants and anti-fogging (to counteract that cloudy look balloons can get), plasticisers (to make it more flexible), preservatives (to enable the balloon to sit in warehouses and store shelves for months), flame retardants, fragrance and, of course, dyes and pigments.

Even more chemicals have to be used to make the additives “stick” to the latex and to stick to each other, enabling them to work in tandem to create a product we expect to use for about 24 hours. So, the balloons can’t be “100% natural rubber latex”.

A little girl on a park bench lets go of a pink balloon
Balloons can travel vast distances in the sky before they pop and are eaten by animals.
Unsplash, CC BY

And yet, despite substantial evidence of harm and the presence of these chemicals, balloon littering persists. Balloon releases are common, with only some regional regulations in place, such as in New South Wales and the Sunshine Coast.

Lying for decades

While some factions of the balloon industry denounce balloon releases, these claims are only recent.

For decades, the industry relied on one industry-funded study from 1989 which claimed that after six short weeks, balloons degraded “at about the same rate as oak tree leaves” and there was no way balloons were a threat to wildlife.

That study was not peer-reviewed, its methods are unclear and not repeatable, and the results are based on only six balloons.




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Avoiding single-use plastic was becoming normal, until coronavirus. Here’s how we can return to good habits


Because balloons are frequently reported to be at sea, ingested by wild animals and washed up on beaches, it’s clear they’re not breaking down in only six weeks. Anecdotal studies have tested this to varying degrees, confirming balloons don’t break down.

Only one peer-reviewed scientific study has quantified balloon degradation, and that also occurred in 1989 — the same year as the industry study. They tested elasticity for up to one year, which means the balloons were intact for that whole time.

Person with a rake buries blue latex balloons in the compost
We tested the claims of the balloon industry.
Dahlia Foo, Author provided

We wanted to know: has anything changed since 1989? And why aren’t there more studies testing balloon degradation, given the passion behind the balloon issue?

So, we set out to quantify exactly how long latex balloons would take to break down. And we asked if balloons degraded differently in different parts of the environment.

Our experiment tested their claims

Industrial composting standards require that the material completely disintegrates after 12 weeks and that the product is not distinguishable from the surrounding soil.

We designed an experiment: after exposing balloons to six hours of sunlight (to simulate typical use, for example, at an outdoor party), we put blue and white balloons in industrial compost, and in saltwater and freshwater tanks.

We allowed for aeration to simulate natural conditions, but otherwise, we left the balloons alone. Every two weeks, we randomly removed 40 balloons from each treatment. We photographed them to document degradation. Then we tested them.

The author prepares to sample latex balloons in front of water tanks
The author sampling latex balloons.
Jesse Benjamin, Author provided

Were the balloons still stretchy? We tested this in the University of Tasmania engineering lab to determine tensile (resistence) strength. We found that in water tanks, the balloons became less stretchy, losing around 75% of their tensile strength. But if they had been composted, balloons retained their stretchiness.

Were the balloons still composed of the same things they started with? We tested this by taking spectral measurements of the balloons’ surface. The balloons showed signs they were exposed to ultra violet light in the water tanks, but not in the compost. This means their chemical composition changed in water, but only slightly.

Finally, and most importantly, did the balloons lose mass?

After 16 weeks, the balloons were still recognisably balloons, though they behaved a little differently in compost, water and saltwater. Some balloons lost 1–2% mass, and some balloons in freshwater gained mass, likely due to osmotic absorption of water.

Four dirty, deflated white balloons in a row on a black background.
These are white latex balloons 16 weeks after we composted them.
Jesse Benjamin, Author provided

What can we do?

It’s clear latex balloons don’t meaningfully degrade in 16 weeks and will continue to pose a threat to wildlife. So what can we do as consumers? We offer these tips:

  • do not release balloons outdoors
  • do not use helium-filled balloons outdoors (this prevents accidental release, and saves helium), which is a critically limited resource
  • if you use balloons, deflate and bin them after use
  • consider balloon alternatives, like bubbles
  • make educated purchases with federal Green Guidelines in mind.



Read more:
There are some single-use plastics we truly need. The rest we can live without


The Conversation


Morgan Gilmour, Adjunct Researcher in Marine Science, University of Tasmania and Jennifer Lavers, Lecturer in Marine Science, University of Tasmania

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How Earth’s plastic pollution problem could look by 2040



Rich Carey/Shutterstock

Costas Velis, University of Leeds and Ed Cook, University of Leeds

During a visit to a bookstore a few weeks ago, we couldn’t help but stare at a display unit featuring no fewer than ten books telling you how to rid plastics from your daily life. We’re bombarded by information on the topic of marine litter and plastic pollution, but how much do we really know about the problem?

Think about other planetary challenges, like climate change or ozone layer depletion. Mature areas of research have developed around them, allowing scientists to identify where the gases that cause these problems come from, and how much reaches the atmosphere each year.

But when it comes to plastic pollution, we know close to nothing about how and where plastic waste is generated, managed, treated and disposed of, especially in low and middle income countries. As a result, we’re struggling to limit the amount of litter accumulating in the environment.

Our research published in Science involved a herculean effort to spot, track and model the current and future flows of plastics into the world’s land and waterbodies. We found that plastic entering the marine environment is set to double by 2040 and, unless the world acts, more than 1.3 billion tonnes of plastic waste will be dumped on land and in waterbodies.

By identifying the ways in which this litter is produced and distributed, we’ve also discovered how best to reduce the plastic deluge. In the process, we found the unsung heroes on the frontline fighting the pollution crisis who could be the world’s best hope of stemming the tide.

Discarded face masks on a rocky beach.
Single-use plastic consumption has increased during the pandemic.
Fevziie/Shutterstock

The world’s plastic problem in numbers

We developed a model called Plastic-to-Ocean (P₂O) which combines years of accumulated knowledge on global flows of plastic. It compares our current production, use and management of waste with what is projected in the future.

Do you burn your waste in the garden or in the street? Do you drop it into the river? If you answered no to both of these questions then you are possibly one of the 5.5 billion people whose waste gets collected. If you were among the remaining two billion, what would you do with your uncollected waste? Would you make use of a nearby stream, cliff edge, or perhaps squirrel the odd bag in the woods after dusk?

More often than not, uncollected plastic waste is simply set on fire as a cost-free and effective method of disposal. Our model suggests that cumulatively, more than 2.2 billion tonnes of plastic will be open burned by 2040, far more than the 850 million tonnes that’s anticipated to be dumped on land and the 480 million tonnes in rivers and seas.

Having tracked the sources of plastic items through the supply chain and their fate in the environment, we explored what might help reduce aquatic pollution. We found that the single most effective intervention is to provide a service for the two billion people who currently don’t have their waste collected.

A graph showing how different measures could reduce the flow of plastic into the ocean.

Breaking the Plastic Wave, Author provided

But, of the nine interventions we tested, none solved the problem on their own. Only an integrated approach that in addition to increasing collection coverage includes interventions such as reducing demand for single-use and unrecyclable plastic and improving the business case for mechanical recycling, could be successful. For the countries suffering most from plastic pollution, this knowledge could offer a way forward.

But even in our best-case scenario, in which the world takes the kind of concerted and immediate action proposed in our study, approximately 710 million tonnes of plastic waste will be released into the environment by 2040. That may sound a lot, but it would mean an 80% reduction in the levels of plastic pollution compared to what will happen with no action over the next two decades.




Read more:
The ocean’s plastic problem is closer to home than scientists first thought


Could waste pickers save the day?

Our work also cast light on the contributions of 11 million waste pickers in low and middle-income countries. These informal workers collect waste items, including plastics, for recycling, to secure a livelihood for day-to-day survival. The model estimates that they may be responsible for 58% of all plastic waste collected for recycling worldwide – more than the combined formal collection services achieve throughout all the high-income countries put together.

Without this informal waste collection sector, the mass of plastic entering rivers and the ocean would be considerably greater. Their efforts should be integrated into municipal waste management plans, not only to recognise their tremendous contribution but to improve the appalling safety standards that they currently endure.

A man in India peddles a bicycle cart to collect rubbish.
An additional 500,000 people will need to be reached by waste collection services each day until 2040.
EPA-EFE/JAIPAL SINGH

Establishing a comprehensive baseline estimate of sources, stocks and flows of plastic pollution, and then projecting into the future, has been an immense task. When it comes to solid waste, the availability, accuracy and international compatibility of data is notoriously insufficient.

Plastic items occur throughout the world in tens of thousands of shapes, sizes, polymer types and additive combinations. There are also considerable differences in cultural attitudes towards the way waste is managed, how plastic products are consumed, and the types of infrastructure and equipment used to manage it when it becomes waste.

Our modelling effort was a delicate and tedious exercise of simplifying and generalising this complexity. To understand how reliable, accurate, and precise our findings are likely to be, think of the first models that estimated how sensitive the climate is to human influence back in the 1970s.

Hopefully, the strong evidence base we have presented today will inform a global strategy and strong local preventive action. The plastic pollution challenge can be substantially controlled within a generation’s time. So, is anyone ready to act?The Conversation

Costas Velis, Lecturer in Resource Efficiency Systems, University of Leeds and Ed Cook, Research Fellow in Circular Economy Systems, University of Leeds

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Waste not, want not: Morrison government’s $1b recycling plan must include avoiding waste in the first place



Mick Tsikas/AAP

Trevor Thornton, Deakin University

The federal government today announced A$190 million in funding for new recycling infrastructure, as it seeks to divert more than ten million tonnes of waste from landfill and create 10,000 jobs.

The plan, dubbed the Recycling Modernisation Fund, requires matching funding from the states and territories. The federal government hopes it will attract A$600 million in private investment, bringing the total plan to about A$1 billion.

The policy is a welcome step to addressing Australia’s waste crisis. In 2016-17, Australians generated 67 million tonnes of waste, and the volume is growing.

Australia’s domestic recycling industry cannot sort the types and volumes of materials we generate, and recent waste import bans in other countries mean our waste often has nowhere to go.

But recycling infrastructure alone is not enough to solve Australia’s waste problem. We must also focus on waste avoidance, reducing contamination and creating markets for recycled materials.

Waste avoidance is even more important than recycling.
Mick Tsikas/AAP

A home-grown problem

In early 2018, China began restricting the import of recyclables from many countries, including Australia, arguing it was too contaminated to recycle. Several other countries including India and Taiwan soon followed.

The move sent the Australian waste management industry into a spin. Recyclable material such as plastic, paper, glass and tyres was stockpiled in warehouses or worse, dumped in landfill.




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How recycling is actually sorted, and why Australia is quite bad at it


It was clear Australia needed to start processing more of its waste onshore, and pressure was on governments to find a solution. In 2019, state and federal governments announced a waste export ban.

Then came today’s announcement. In addition to the A$190 million for recycling infrastructure announced, the federal government will:

  • spend A$35 million on meeting its commitments under the National Waste Policy Action Plan

  • spend A$24.6 million on Commonwealth commitments to improve national waste data and determine if we’re meeting recycling targets

  • introduce new federal waste legislation to formalise the waste export ban and encourage companies to take responsibility for the waste they create.

But key questions remain: will the full funding package be delivered, and will it be spent where it’s needed?

Overseas bans on foreign waste pose a problem for Australia.
Fully Handoko/EPA

Clarity is needed

The Commonwealth says its funding is contingent on contributions from industry, states and territories. It’s not clear what happens to the plan if this co-funding does not eventuate.

Figures from the Australian Council of Recyclers shows state governments have not always been willing to spend on waste management. Of about A$2.6 billion in waste levies collected from businesses and households over the past two years, only 16.7% has been spent on waste, recycling and resource recovery.

There’s been a recent increase in the volume and type of materials placed into recycling and waste streams. But a lack of funding to date meant the industry struggled to manage these changes.

Some state governments have recently made positive moves towards spending on waste management infrastructure, and it’s not clear what the federal plan means for these commitments. Victoria, for example, has a A$300 million plan to transform the recycling sector. Will it now be asked to spend more?

Recycling infrastructure is not enough

The federal announcement made no mention of the three other pillars in successful waste management: waste avoidance, reducing contamination and creating markets for recycled materials.

The 2018 National Waste Policy says waste “avoidance” is the first principle in waste management, stating:

Prioritise waste avoidance, encourage efficient use, reuse and repair. Design products so waste is minimised, they are made to last and we can more easily recover materials.

States have collected billions in waste levies, but spent little on the problem.
Dave Hunt/AAP

Avoiding the generation of waste in the first place reduces the need for recycling. Waste avoidance also means we consume less resources, which is good for the planet and our economy.

Addressing contamination in our recycling streams is also vital. Contaminants include soft plastics, disposable nappies and textiles. If these items end up in this stream, recyclers must remove and dispose of them, adding time and costs to the process.

Addressing the contamination issue would also reduce the amount of new infrastructure required.

Public education and enforcement is urgently needed to reduce recycling contamination and increase waste avoidance, yet government action has been lacking in this area.

Businesses have great potential to reduce costs associated with managing waste. This includes reducing the waste of raw materials as well as improving the segregation of wastes and recyclables. Funding is desperately needed to help businesses implement these changes.

The federal government says the new funding could be used for small, portable waste-sorting facilities. This is a great idea. They could be located in rural and regional areas, and even at large events so materials can be effectively sorted at the source. This would make sorting more efficient and may also reduce the need for waste transport.




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Four bins might help, but to solve our waste crisis we need a strong market for recycled products


And of course, there’s no use producing recycled materials if no-one wants to buy them. Plenty of products could be produced using recycled glass, plastics, textiles and so on, but the practice in Australia is fairly limited. One promising example involves using glass and plastic in road bases.

Governments, business and even consumers can do more to demand that the products they buy contain a proportion of recycled materials, where its possible for a manufacturer to do so.

Why send material to landfill when it can be recycled?
AAP

A sustainable future

The government’s funding to improve waste data is welcome, and will allow improvements to the waste system to be accurately measured. Currently, many waste databases measure measure our recycling rate according to what goes into the recycling bins, rather than what actually ends up being recycled.

Spending to support actions under the National Waste Policy is also positive, as long as it spent primarily on reducing waste from being created in the first place.

Done right, better waste management can stimulate the economy and help improve the environment. Today’s announcement is a good step, but more detail is needed. Clearly though, it’s time for Australians to think more carefully about the materials we dispose of, and put them to better use.




Read more:
Recycling plastic bottles is good, but reusing them is better


The Conversation


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

This article is republished from The Conversation under a Creative Commons license. Read the original article.

After a storm, microplastics in Sydney’s Cooks River increased 40 fold



A litter trap in Cook’s River.
James HItchcock, Author provided

James Hitchcock, University of Canberra

Each year the ocean is inundated with 4.8 to 12.7 million tonnes of plastic washed in from land. A big proportion of this plastic is between 0.001 to 5 millimetres, and called “microplastic”.

But what happens during a storm, when lashings of rain funnel even more water from urban land into waterways? To date, no one has studied just how important storm events may be in polluting waterways with microplastics.




Read more:
Microplastic pollution is everywhere, but scientists are still learning how it harms wildlife


So to find out, I studied my local waterway in Sydney, the Cooks River estuary. I headed out daily to measure how many microplastics were in the water, before, during, and after a major storm event in October, 2018.

The results, published on Wednesday, were startling. Microplastic particles in the river had increased more than 40 fold from the storm.

Particles of plastic found in rivers. They may be tiny, but they’re devastating to wildlife in waterways.
Author provided

To inner west Sydneysiders, the Cooks River is known to be particularly polluted. But it’s largely similar to many urban catchments around the world.

If the relationship between storm events and microplastic I found in the Cooks River holds for other urban rivers, then the concentrations of microplastics we’re exposing aquatic animals to is far higher than previously thought.

14 million plastic particles

They may be tiny, but microplastics are a major concern for aquatic life and food webs. Animals such as small fish and zooplankton directly consume the particles, and ingesting microplastics has the potential to slow growth, interfere with reproduction, and cause death.

Determining exactly how much microplastic enters rivers during storms required the rather unglamorous task of standing in the rain to collect water samples, while watching streams of unwanted debris float by (highlights included a fire extinguisher, a two-piece suit, and a litany of tennis balls).

Back in the laboratory, a multi-stage process is used to separate microplastics. This includes floating, filtering, and using strong chemical solutions to dissolve non-plastic items, before identification and counting with specialised microscopes.

Litter caught in a trap in Cooks River. These traps aren’t effective at catching microplastic.
Author provided

In the days before the October 2018 storm, there were 0.4 particles of microplastic per litre of water in the Cooks River. That jumped to 17.4 microplastics per litre after the storm.

Overall, that number averages to a total of 13.8 million microplastic particles floating around in the Cooks River estuary in the days after the storm.




Read more:
Seafloor currents sweep microplastics into deep-sea hotspots of ocean life


In other urban waterways around the world scientists have found similarly high numbers of microplastic.

For example in China’s Pearl River, microplastic averages 19.9 particles per litre. In the Mississippi River in the US, microplastic ranges from 28 to 60 particles per litre.

Where do microplastics come from?

We know runoff during storms is one of the main ways pollutants such as sediments and heavy metals end up in waterways. But not much is known about how microplastic gets there.

However think about your street. Wherever you see litter, there are also probably microplastics you cannot see that will eventually work their way into waterways when it rains.




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Many other sources of microplastics are less obvious. Car tyres, for example, which typically contain more plastic than rubber, are a major source of microplastics in our waterways. When your tyres lose tread over time, microscopic tyre fragments are left on roads.

Did you know your car tyres can be a major source of microplastic pollution?
Shutterstock

Microplastics may even build up on roads and rooftops from atmospheric deposition. Everyday, lightweight microplastics such as microfibres from synthetic clothing are carried in the wind, settling and accumulating before they’re washed into rivers and streams.

What’s more, during storms wastewater systems may overflow, contaminating waterways. Along with sewage, this can include high concentrations of synthetic microfibers from household washing machines.

And in regional areas, microplastics may be washing in from agricultural soils. Sewage sludge is often applied to soils as it is rich in nutrients, but the same sludge is also rich in microplastics.

What can be done?

There are many ways to mitigate the negative effects of stormwater on waterways.

Screens, traps, and booms can be fitted to outlets and rivers and catch large pieces of litter such as bottles and packaging. But how useful these approaches are for microplastics is unknown.

Raingardens and retention ponds are used to catch and slow stormwater down, allowing pollutants to drop to bottom rather than being transported into rivers. Artificial wetlands work in similar ways, diverting stormwater to allow natural processes to remove toxins from the water.

Almost 14 million plastic particles were floating in Cooks River after a storm two years ago.
Shutterstock

But while mitigating the effects of stormwater carrying microplastics is important, the only way we’ll truly stop this pollution is to reduce our reliance on plastic. We must develop policies to reduce and regulate how much plastic material is produced and sold.

Plastic is ubiquitous, and its production around the world hasn’t slowed, reaching 359 million tonnes each year. Many countries now have or plan to introduce laws regulating the sale or production of some items such as plastic bags, single-use plastics and microbeads in cleaning products.




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We have no idea how much microplastic is in Australia’s soil (but it could be a lot)


In Australia, most state governments have committed to banning plastic bags, but there are still no laws banning the use of microplastics in cleaning or cosmetic products, or single-use plastics.

We’ve made a good start, but we’ll need deeper changes to what we produce and consume to stem the tide of microplastics in our waterways.The Conversation

James Hitchcock, Post-Doctoral Research Fellow, University of Canberra

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Seafloor currents sweep microplastics into deep-sea hotspots of ocean life



A rockfish hides in a red tree coral in the deep sea.
Geofflos

Ian Kane, University of Manchester and Michael Clare, National Oceanography Centre

What if the “great ocean garbage patches” were just the tip of the iceberg? While more than ten million tonnes of plastic waste enters the sea each year, we actually see just 1% of it – the portion that floats on the ocean surface. What happens to the missing 99% has been unclear for a while.

Plastic debris is gradually broken down into smaller and smaller fragments in the ocean, until it forms particles smaller than 5mm, known as microplastics. Our new research shows that powerful currents sweep these microplastics along the seafloor into large “drifts”, which concentrate them in astounding quantities. We found up to 1.9 million pieces of microplastic in a 5cm-thick layer covering just one square metre – the highest levels of microplastics yet recorded on the ocean floor.

While microplastics have been found on the seafloor worldwide, scientists weren’t sure how they got there and how they spread. We thought that microplastics would separate out according to how big or dense they were, in a similar manner to natural sediment. But plastics are different – some float, but more than half of them sink.




Read more:
Pristine Antarctic fjords contain similar levels of microplastics to open oceans near big civilisations


Plastics which once floated can sink as they become coated in algae, or if bound up with other sticky minerals and organic matter. Recent research has shown that rivers transport microplastics to the ocean too, and laboratory experiments revealed that giant underwater avalanches of sediment can transport these tiny particles along deep-sea canyons to greater depths.

We’ve now discovered how a global network of deep-sea currents transports microplastics, creating plastic hotspots within vast sediment drifts. By catching a ride on these currents, microplastics may be accumulating where deep-sea life is abundant.

Once plastic debris has broken down and sinks to the ocean floor, currents sweep the particles into vast drifts.
Ian Kane, Author provided

From bedroom floors to the seafloor

We surveyed an area of the Mediterranean off the western coast of Italy, known as the Tyrrhenian Sea, and studied the bottom currents that flow near the seafloor. These currents are driven by differences in water salinity and temperature as part of a system of ocean circulation that spans the globe. Seafloor drifts of sediment can be many kilometres across and hundreds of metres high, forming where these currents lose their strength.

We analysed sediment samples from the seafloor taken at depths of several hundred metres. To avoid disturbing the surface layer of sediment, we used samples taken with box-cores, which are like big cookie cutters. In the laboratory, we separated microplastics from the sediment and counted them under microscopes, analysing them using infra-red spectroscopy to find out what kinds of plastic polymer types were there.

A microplastic fibre seen under a microscope.
Ian Kane, Author provided

Most microplastics found on the seafloor are fibres from clothes and textiles. These are particularly insidious, as they can be eaten and absorbed by organisms. Although microplastics on their own are often non-toxic, studies show the build-up of toxins on their surfaces can harm organisms if ingested.

These deep ocean currents also carry oxygenated water and nutrients, meaning that the seafloor hotspots where microplastics accumulate may also be home to important ecosystems such as deep-sea coral reefs that have evolved to depend on these flows, but are now receiving huge quantities of microplastics instead.

What was once a hidden problem has now been uncovered – natural currents and the flow of plastic waste into the ocean are turning parts of the seafloor into repositories for microplastics. The cheap plastic goods we take for granted eventually end up somewhere. The clothes that may only last weeks in your wardrobe linger for decades to centuries on the seafloor, potentially harming the unique and poorly understood creatures that live there.The Conversation

Ian Kane, Reader in Geology, University of Manchester and Michael Clare, Principal Researcher in Marine Geoscience, National Oceanography Centre

This article is republished from The Conversation under a Creative Commons license. Read the original article.