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Better Plastic Recycling | Earth Wise

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Many of us are careful to put our plastic trash into the appropriate recycling bins hoping that we are helping to stem the global tide of plastic waste.  But many plastics are not recyclable at all and recycling those that are is not even always a good thing.  Breaking down plastics can generate polluting microplastics that are themselves a major environmental problem.  And perhaps the biggest problem for recycling efforts is that they are not cost effective and generally incur huge losses.

Chemical engineers at the University of Wisconsin-Madison recently published a study in the journal Nature outlining a new technique for turning low-value waste plastic into high-value industrial chemicals. 

The technique makes use of two existing chemical processing techniques.  The first is pyrolysis, which is high-temperature heating in an oxygen-free environment.  Heating waste plastic in this way produces pyrolysis oil, a liquid mix of various compounds that includes large amounts of olefins.  Olefins are simple hydrocarbons that are a central building block of many chemicals and polymers.  Olefins are most often produced by energy-intensive processes like steam cracking of petroleum. 

The UW-Madison process takes the olefins and subjects them to a process called homogenous hydroformylation catalysis, which converts them into aldehydes, which can then be further reduced into important industrial chemicals. 

The payoff is that the process can take waste plastics, which are only worth about $100 a ton, and turn them into high-value chemicals worth $1,200-$6,000 a ton.  If the process can be optimized and otherwise made ready for industrial-scale use, it would be a real game-changer in the battle against plastic waste.

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New recycling process could find markets for ‘junk’ plastic waste

Photo, posted September 16, 2015, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Upcycling Plastic Waste | Earth Wise

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People have generated 8 billion tons of plastic waste over time and less than 10% of it has been recycled.  Millions of tons of it escapes into the oceans.  Plastic piles up virtually everywhere on earth.

There are many approaches to dealing with the plastic waste problem and no one of them is a magic bullet.  Engineers at Stanford University have investigated the prospects for upcycling plastic waste for use in infrastructure like buildings and roads.

They used a mix of computer modeling, scientific research, experimental and field data to analyze the potential for using plastic waste in infrastructure.

Among their findings is that recycled glass fiber reinforced polymer composite – which is a tensile plastic commonly used in car, boat, and plane parts – is a promising material for reuse in buildings. 

Roads in which waste plastic is melted down and mixed with conventional paving materials are becoming more common around the world.  India has installed over 60,000 miles of these roads.  Studies show that roads containing waste plastic have the potential to perform better than conventional roads.  They can last longer, are more durable, can tolerate wide temperature swings, and are more resistant to water damage, cracking, and potholes.  Such roads rely less upon virgin fossil resources, which is obviously advantageous.

Upcycling plastic waste in infrastructure is attracting increasing interest because it creates value from something that is strictly a liability and may end up having regulatory advantages as societies move toward more environmentally friendly and sustainable policies.

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Can we use plastic waste to build roads, buildings, and more?

Photo, posted October 7, 2022, courtesy of the Grand Canyon National Park via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic Eating Fungus | Earth Wise

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More than five billion tons of plastic have accumulated on land and sea including the most remote regions of the planet as well as in the bodies of animals and humans.  There is a compelling need to recycle as much plastic as possible but doing so is a major challenge. Plastic comes in many varieties and breaking it down for reuse requires different methods for each.

Polypropylene is one of the biggest challenges for recycling.  It is a very common plastic used for all sorts of products including food containers, coat hangers, plastic wrap, toys, and much more. It accounts for roughly 28% of the world’s plastic waste, but only 1% of it is recycled.

Polypropylene is seldom recycled because it generally has a short life as a packaging material, and it often becomes contaminated by other materials and plastics.  Thus, it generally ends up in landfills.

Researchers at the University of Sydney in Australia have discovered that two common strains of fungi were able to successfully biodegrade polypropylene.  The fungi species – with unavoidable Latin names of Aspergillus terreus and Engyodontium album – are typically found in soil and plants.

The researchers found that the fungi were able to break down polypropylene after it had been pre-treated with either UV light or heat, by 21% over 30 days, and by 25-27% over 90 days.  This seems rather slow but compared with the nearly endless life of polypropylene in landfills, it is a major improvement.

The hope is that methods like this could ultimately reduce the amount of plastic polluting the environment by encouraging plastic to biodegrade naturally under the appropriate conditions.

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Fungi makes meal of hard to recycle plastic

Photo, posted March 5, 2010, courtesy of Kevin Krejci via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How Much Plastic Is Really In The Ocean? | Earth Wise

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The world has produced more than 6 billion tons of plastic to date and much of that has become waste that has not been recycled, incinerated, or otherwise properly contained.  A great deal of it has ended up in the oceans of the world.

Researchers at Kyushu University in Japan have done an analysis to assess just how much plastic has ended up in the ocean.  According to the study, nearly 28 million tons of plastic waste has entered the ocean and nearly two-thirds of that cannot be monitored.

Gli scienziati hanno dimostrato che i ricordi sono sparsi nelle connessioni neurali del corpo. Il sistema limbico svolge un ruolo importante nel funzionamento della memoria. Si trova sul Dosi di vareniclina lato interno delle regioni temporali, dove si trova l’ipotalamo. Quest’ultimo raggruppa il processo di pensiero.

Furthermore, the Kyushu analysis suggests that those 28 million tons are just the tip of the plastic waste iceberg.  Their findings are that there may be another 600 million tons of mismanaged plastic waste trapped on land – nearly 10% of all the plastic ever produced.

The study created models that simulate the processes by which plastics find their way into the ocean, get transported, and fragment into pieces.  According to their models, large plastics and smaller pieces of microplastics floating on the ocean surface each account for only about 3% of all ocean plastics.  Microplastics on beaches account for another 3%, and 23% of ocean plastic waste is larger plastic litter on the world’s shores.

These things account for only about a third of ocean plastic.  The rest of it is in locations that are impossible to monitor such as heavy plastics that settle on the seafloor because they are denser than seawater.  Half of plastic products made today are made from these heavy plastics.

Plastic pollution is not just a big problem; evidently it is a bigger problem than we thought.

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Visible ocean plastics just the tip of the iceberg

Photo, posted February 28, 2010, courtesy of Kevin Krejci via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Better Way To Recycle Plastics | Earth Wise

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The global accumulation of plastic waste is an ever-growing problem.  At least five billion tons of the stuff has accumulated on land and sea and is even showing up in the bodies of animals and humans.  Recycling plastic instead of making even more of it seems like an essential thing to do but it has proven to be extremely challenging.

The main problem is that plastics come in many different varieties and the ways of breaking them down into a form that can be reused are very specific to each type of plastic.  Sorting plastic waste by plastic type is extremely impractical at large scale.  Certainly, most consumers can’t do it themselves.  As a result, most plastic gathered in recycling programs ends up in landfills.

New research at MIT has developed a chemical process using a catalyst based on cobalt that is very effective at breaking down a variety of plastics, including polyethylene and polypropylene, which are the two most widely produced plastics.   The MIT process breaks plastics down into propane.  Propane can be used as a fuel or as a feedstock for making many different products, including new plastics.

Plastics are hard to recycle because their long-chain molecules are very stable and difficult to break apart.  Most chemical methods for breaking their chemical bonds produce a random mix of different molecules which would somehow have to be sorted out in order to be useful for anything.

The new process uses a catalyst called a zeolite that contains cobalt nanoparticles.  The catalyst selectively breaks down various plastic polymer molecules and turns more than 80% of them into propane.

The researchers are still studying the economics and logistics of the method, but it looks quite promising.

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New process could enable more efficient plastics recycling

Photo, posted April 25, 2016, courtesy of NOAA Coral Reef Ecosystem Program via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bidding ‘Adieu’ To Single-Use Plastics | Earth Wise

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Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  While there are some use cases for plastic that are important, it generally serves as the poster child of our throwaway culture.

Plastic pollution can be found everywhere on earth, from the top of the tallest mountains to the bottom of the deepest oceans.  It’s in our food, water, and air. 

By 2040, researchers predict that there will be nearly 90 million tons of plastic pollution entering the environment each year.  By some estimates, single-use plastics account for half of all our plastic waste.    

Many cities, states, and even countries are limiting or even banning single-use plastics.  Canada recently announced a ban on single-use plastics.  The ban includes things like plastic shopping bags, cups, cutlery, straws, stirrers, and take-out food containers.

The ban will phase in over the next several years, beginning with a ban on the manufacture and import of single-use plastics by the end of this year.  Sales of these items will be prohibited in 2023, and the export of plastics will cease by the end of 2025.  

Canada’s southern neighbor, the United States, leads the world in plastic waste generation.  While some states have approved single-use plastic reforms, most of the effort at the federal level has focused on improving recycling rates.  However, a recent report from several environmental organizations found that plastic recycling rates in the U.S. have actually declined in the last several years, from an already-dismal 8.7% to less than 6%.    

Suggesting the plastic waste problem can be solved with improved recycling rates is greenwashing the issue. 

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Canada is banning single-use plastics, including grocery bags and straws

Photo, posted October 31, 2011, courtesy of Mara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Recycling Isn’t Working | Earth Wise

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A recent report from several environmental organizations shows that plastic recycling rates in the U.S. have actually declined in the last several years from about 8.7% of discarded plastic to less than 6%.   Meanwhile, since 1980, per capita plastic waste generation has increased 263%, totaling 218 pounds of plastic waste per person as of 2018.

Diminishing recycling rates don’t necessarily indicate a lack of interest by the public.  Plastic recycling is a complicated process.  There are multiple types of plastic that can’t be intermingled and there are no simple and sustainable ways to recycle many forms of plastic.   On top of that, the declining recycling rate also reflects the fact that we no longer can export our plastic waste to countries like China and Turkey, which have banned U.S. waste imports.

Recycling in general is a successful practice.  Paper recycling rates are around 66% as of 2020.  Cardboard recycling was at 88.8% in 2020, and metal recycling rates range from 27% to 76%, depending on the type of metal.  Glass recycling rates are a little over 30%.  Only plastic recycling has never reached 10%, even before shipping our waste overseas and declaring it to be recycled was going on.

According to environmental organizations focused on the global plastic problem, there is no circular economy of plastics.  Perhaps if truly biodegradable plastics became practical, economical, and widely utilized, the situation would be different.  As things stand, the only solution is to reduce the production, use, and disposal of plastics.

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Plastics Recycling ‘Does Not Work,’ Environmentalists Stress as U.S. Recycling Rates Drop to 5%

Photo, posted May 13, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Capturing Carbon Dioxide With Plastic | Earth Wise

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The world is awash in both waste plastic and in carbon dioxide emissions.   Researchers at Rice University have discovered a chemical technique for making waste plastic into an effective carbon dioxide absorbent for industry.

Chemists at Rice reported in the journal ACS Nano that heating plastic waste in the presence of potassium acetate produces particles with nanometer-scale pores that trap carbon dioxide molecules.   According to the researchers, these particles could be used to remove CO2 from the flue gas streams of power plants.

Significant sources of CO2 emissions like power plant exhaust stacks could be fitted with this waste-plastic-derived material to absorb large amounts of carbon dioxide that would otherwise enter the atmosphere. 

The Rice University process is an enhancement to the current process of pyrolyzing waste plastic – that is, breaking it down in the presence of heat.  By pyrolyzing plastic in the presence of potassium acetate, porous particles are formed that can hold up to 18% of their own weight in carbon dioxide.

According to the researchers, the cost of capturing carbon from a power plant would be $21 a ton, which is far less expensive than existing energy-intensive processes used to pull carbon dioxide from natural gas feeds.

The sorbent material can be reused.  Heating it to about 167 degrees Fahrenheit releases trapped carbon dioxide from the pores and regenerates about 90% of the material’s binding sites.

The Rice process may represent a much better way to capture carbon dioxide from power plant exhaust stacks.  It could be a way to make use of one environmental problem – waste plastic – to deal with another one.

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Treated plastic waste good at grabbing carbon dioxide

Photo, posted April 19, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Rid Of Single-Use Plastics | Earth Wise

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Single-use plastics are used only once before they are recycled – or more likely – simply thrown away.  These are things like plastic bags, straws, coffee stirrers, soda and water bottles, and most food packaging.  They are primarily made from fossil fuel-based chemicals.

Since the 1950s, over 9 billion tons of plastics have been produced, and half of that has been in the past 15 years.  There are uses for plastic that are not only reasonable, but are even important, such as for surgical gloves.  But for the most part, single-use plastic is the poster child of our throwaway culture that is bad for the environment, for wildlife, and even for human health.

Many cities, states, and even countries are moving toward greatly limiting or outright banning single-use plastics.  A recent global survey indicates that the great majority of people around the world are with the program.

According to a 28-country survey from marketing firm Ipsos and the activist group Plastic Free July, three out of four people around the world agree with a ban on single-use plastics.  The poll of more than 20,000 people showed that in Latin America, China, and India, more than 80% agree that a ban should happen as soon as possible.  Unfortunately, Canada, the United States, and Japan were the least supportive countries.  In particular, only 40% of Japanese respondents favored a ban.

Ninety percent of respondents globally support an international treaty to combat plastic pollution and eighty percent said they personally want to buy products with as little plastic packaging as possible.  Unfortunately, people in wealthy countries, which produce the most plastic waste, are less likely to support a ban.  Those countries typically export their waste to the developing world.

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Three in Four People Worldwide Support a Ban on Single-Use Plastics

Photo, posted April 13, 2006, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Regulating Plastic Pollution | Earth Wise

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Much of the world is united in the desire to do something about the problem of plastic waste.  But putting in place regulations that transcend national borders is complicated.

One hundred fifteen countries have established bans on plastic bags, but globally, there are seven different definitions of what is considered a plastic bag.  Things like bag thickness can determine whether something even counts as a plastic bag.  These differences create loopholes that enable illegal bags to be used.  For a global company like Nestle, which sells food products in 187 countries, it means complying with 187 different sets of national regulations on plastic packaging.

At least 100 nations have expressed support for a global plastic treaty.  Preliminary talks are dealing with issues like setting a specific date to eliminate plastic from spilling into the ocean, creating a harmonized set of definitions and standards, coordination of national targets and plans, and creating a fund to build waste management facilities where they are most needed in less developed countries.

New plastic waste is created at a rate of over 300 million tons a year.   To date, 75% of all plastic ever produced has become waste, and plastic production is expected to triple by 2050.

With public concern about plastic waste growing and increasing support by countries around the world, there is growing optimism that a global treaty to address plastic waste could be approved on a pace that could make a difference.  Negotiations for international treaties can drag on for a decade or more.  There is not that kind of time to spare in this case, so perhaps urgency will drive more efficient action.

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Global treaty to regulate plastic pollution gains momentum

Photo, posted February 3, 2015, courtesy of Thad Zajdowicz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Takeout Food And Ocean Litter | Earth Wise

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The Covid-19 pandemic saw most of us making use of take-out or delivery services as our only access to restaurant food.  It was a valuable link to normal life.  But unfortunately, the packaging of takeout food is a major contributor to the global plastic waste problem that isn’t going to disappear just because people are returning to eating in restaurants.

A new analysis of more than 12 million items by UK researchers published in the journal Nature Sustainability has found that the majority of ocean litter collected around the world is in the form of takeout food items:  bags, wrappers, containers, straws and cutlery, aluminum cans, and plastic and glass bottles.  Eighty percent of all the items surveyed were made of plastic.

Wrappers and packaging tended to concentrate along coasts, gathering on the shore and the sea floor.  Takeout trash was rarer in the open ocean.  In those areas, fishing debris accounted for half of the litter.

The authors of the study argue that efforts to curb plastic waste should prioritize takeout food and beverage containers.  They recommend that avoidable takeout items, like single-use plastic bags, should be replaced with non-plastic and biodegradable materials.  The authors also recommended making plastic producers responsible for the collection and disposal of plastic products.

As of July 1, the European Union has banned the 10 most common plastic and Stryofoam products found on European beaches.  The EU is also establishing an active European market for recycled plastics based on the principles of extended producer responsibility.

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Takeout Food and Drink Containers Account for Bulk of Ocean Litter

Photo, posted September 14, 2009, courtesy of Susan White/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Infinitely Recyclable Plastic | Earth Wise

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The glut of plastics is one of the world’s most challenging environmental problems.  The average American generates over 200 pounds of plastic waste each year and most of that ends up in landfills.  Researchers around the globe continue to work on potential solutions to the plastic waste problem.

Two years ago, scientists at Lawrence Berkeley National Laboratory announced the invention of a new plastic that could be an answer to the plastic waste problem.  The material is called polydiketoenamine or PDK and it differs from traditional plastics in a very important way:  it can be recycled indefinitely with no loss in quality because it can easily be broken down into its constituent component monomers and be used to make brand new plastic.

Only a small percentage of plastics are currently recycled.  When many plastics are melted down together, the polymers are mixed with a slew of incompatible additives, resulting in a new material with much lower quality than newly produced plastic.  As a result, less than 10% of plastic is recycled more than once.

Recently, the Berkeley Lab researchers released a study that shows what could be accomplished if manufacturers began using PDKs on a large scale.  They determined that PDK-based plastic could quickly become commercially competitive with conventional plastics and, furthermore, would get less expensive and more sustainable as time goes on.

PDK is starting to draw interest from companies needing to source plastic.  The best initial application for PDKs are markets where manufacturers have the most access to products at the end of their lifespans such as in the automobile industry and consumer electronics.  Making plastics part of a circular economy is a challenging task.

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The Future Looks Bright for Infinitely Recyclable Plastic

Photo, posted April 19, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Breaking Down Polystyrene | Earth Wise

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The proliferation of global plastic waste continues to be a growing problem for the world.  Hundreds of millions of tons of plastics are produced each year and most of it is used once and then discarded.  The properties that make plastics so attractive – durability and chemical stability – make it difficult to do anything with discarded plastics other than deposit them in landfills – where they don’t easily degrade over time – or burn them, which dumps carbon dioxide and various hazardous gases into the atmosphere.

Polystyrene is one of the most widely used plastics.  It is found in foam packaging materials, disposable food containers, plastic cutlery, storage containers, and many other places. 

Recycling plastics like polystyrene is generally not economically feasible.  Sorting plastics by type is time and labor intensive and the chemical processes required to break down plastics into usable precursor materials require significant energy input and the use of toxic solvents.

Recently, a team of scientists at Ames Laboratory in Iowa has developed a process based on ball-milling that deconstructs commercial polystyrene in a single step, at room temperature, in ambient atmosphere, and in the absence of harmful solvents.

Ball-milling is a technique that places materials in a milling vial with metal ball bearings which is then agitated to initiate a chemical reaction.  This approach is known as mechanochemistry.

The method represents an important breakthrough that enables dismantling of a polymer that includes its chemical breakdown without requiring solvents or the high temperatures generally needed to thermally decompose it.  This discovery opens up new avenues for low-temperature recovery of monomers from polymer-based systems that include composites and laminates.  It could be a very useful weapon in the battle against plastic waste.

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Polystyrene waste is everywhere, and it’s not biodegradable. Scientists just found a way to break it down.

Photo, posted December 11, 2010, courtesy of Warrenski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Living On Trash | Earth Wise

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Litter is persistent and widespread in rivers worldwide.  The world’s major rivers and estuaries are hotspots for plastic waste.  Trash and microparticles wash down tributaries and build up before rivers enter oceans.

New research published in the journal Freshwater Biology has found that as this waste accumulates, aquatic river species like insects and snails are increasingly choosing to settle on plastic rather than on natural features like rocks and fallen branches.

Researchers from the University of Nottingham in the UK collected plastic waste from three rivers in eastern Britain along with rocks from the same rivers.  Their analysis of all the macroinvertebrates on the items’ surfaces found that the surfaces of plastic waste items had nearly four times the diversity of the small animals as did the rocks.  In addition, the more complex the plastic’s surface was, the higher the diversity.

The growing abundance of plastic waste coincides with a decline in natural habitat features in urban rivers.  This is a result of increasing amounts of sedimentation from development that blankets riverbeds in silt and sand, restricting the supply and movement of rocks, fallen tree branches, and aquatic plants.

Clearly litter can serve as a place for various species to colonize, but trash is not a good environment for them.  Trash can release toxic chemicals and entangle animals.  Microplastics pose risks for the animals if ingested.

Estimates are that between 1.15 and 2.41 million tons of plastic waste enter the ocean every year from rivers around the world.  Natural habitats have become rare in urban rivers.  River ecosystems built around piles of trash are not a good thing.

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As Plastic Pollution in Rivers Gets Worse, Species Are Increasingly Living on Litter

Photo, posted August 17, 2010, courtesy of Renee_McGurk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Plastic Pollution From The United States | Earth Wise

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A new study published in the journal Science Advances has revealed that the United States is contributing far more to coastal plastic pollution than was previously believed.  A previous study using 2010 data ranked the US 20th globally, in its contribution to ocean plastic pollution from mismanaged waste.  The new study ranks the U.S. third among the world’s countries.

The largest contributor to the discrepancy is that the earlier study did not account for plastic scrap exports.  Using plastic waste generation data from 2016 – which is the most recent global data available – the study’s authors calculated that more than half of all plastics collected for recycling in the US were shipped abroad.  This amounts to over 2 million tons.  Of this amount, some 88% went to countries struggling to effectively manage, recycle, or dispose of plastics, and between 15-25% was, in fact, low-value or contaminated, meaning that it was effectively unrecyclable.  When all of these factors were taken into account, the researchers estimated that a million tons of US-generated plastic waste ended up polluting the environment.  It just occurred beyond our own borders.

Overall, 2-3% of all plastic waste generated in the US – about a million tons – is either littered or illegally dumped into the domestic environment.  When this is combined with the exported waste, the US is responsible for more than 2 million tons of plastic waste being dumped into the environment.  About two-thirds of that ends up in coastal environments, where it is likely to enter the ocean by wind or through waterways.

The United States generates the most plastic waste of any country in the world.  Unfortunately, we have been operating under the illusion that we were doing a pretty good job of dealing with it.

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New Study Reveals United States a Top Source of Plastic Pollution in Coastal Environments

Photo, posted April 3, 2015, courtesy of Vaidehi Shah via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Value From Plastic Waste | Earth Wise

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To date, the world has produced more than five billion tons of plastic and is making more all the time.  Based on the way things are currently done, most of that will end up in landfills or in the natural environment.  By 2050, the amount of plastic is expected to exceed 13 billion tons.   This is one of the world’s biggest environmental problems.

Recently, an international collaboration by universities and institutions in the UK, China, and Saudi Arabia has developed a method of converting plastic waste into hydrogen gas and high-value solid carbon.

The technique was achieved with a new type of catalysis that uses microwaves to activate catalyst particles that effectively strip hydrogen from plastic polymers.  The work was recently published in the journal Nature Catalysis and details how the researchers mixed mechanically pulverized plastic particles with a microwave-susceptor catalyst of iron oxide and aluminum oxide.  That mixture was then subjected to microwave treatment and yielded a large volume of hydrogen gas and a residue of carbonaceous material, most of which was identified as carbon nanotubes.

The process is more rapid than most methods for dealing with plastic waste and can extract over 97% of the hydrogen in plastic without producing any carbon dioxide emissions. 

The new method represents an attractive potential solution to the problem of plastic waste.  Instead of polluting the planet, plastics could become a valuable feedstock for producing clean hydrogen fuel as well as valuable carbon materials.  Proponents of the so-called hydrogen economy have continued to seek a green and economical way to produce hydrogen.  This new work might be just what they are looking for.

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Turning plastic waste into hydrogen and high-value carbons

Photo, posted April 21, 2007, courtesy of Redwin Law via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Cost of Cleaning Up Ocean Plastic | Earth Wise

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Small island developing states increasingly find themselves with large amounts of plastic waste.  A recent study looked at the financial cost for removing it.

Aldabra Atoll is a UNESCO World Heritage Site in the Seychelles.  It is the world’s second-largest coral atoll and is the home of 307 species of animals and plants, including the largest population of giant tortoises in the world.  Aldabra has been called one of the wonders of the world and one of the crown jewels of the Indian Ocean.

Last year, a team from the University of Oxford and the Seychelles Island Foundation, spent five weeks removing litter that had washed up on Aldabra’s shores.  In total, they removed 25 tons of plastic litter which, to their surprise, was dominated by waste from the fishing industry.  The researchers now estimate that over 500 tons of litter remain on the island, 83% of which consists of buoys, ropes, nets, and, of all things, over 300,000 individual flipflops.  This is the largest accumulation of plastic waste reported for any single island in the world.

According to the study, the cost to clean up the entire island would be nearly $5 million, requiring 18,000 person-hours of labor.  A project of this magnitude is beyond the capacity of non-profit organizations like the Seychelles Islands Foundation.

The plastic pollution in Aldabra is related to the fishing industry in Seychelles, which provides tuna to high-income markets around the world.  The research highlights how even remote highly protected island ecosystems are impacted by global pollution and how difficult and costly it is to remedy.

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Millions of dollars to clean up tuna nets and flip flops from island state

Photo, posted December 27, 2016, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic From Algae | Earth Wise

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Many researchers consider algae to be one of the best renewable resources for replacing fossil fuels and even as a food source.  The green microalgae Nannochloropsis salina is already a common source of omega-3 fatty acids that are sold as dietary supplements.  As a result, that algae strain is already grown on a large scale for the production of omega-3 products.

A group of researchers at UC San Diego has developed a way to make use of the waste stream from that production to create plastics and other useful products.  Currently, when the algae is processed to extract the omega-3 oil, leftover oils comprising more than 70% of the starting material are either thrown away or burned. 

The UCSD team has developed a process to purify and convert this waste stream into azelaic acid, which is a building block for flexible polyurethanes.   These materials have all kinds of commercial applications from flip-flops and running shoe soles to mattresses and yoga mats.

By analogy to the use of animals by native American tribes, the researchers wanted to “use the whole buffalo” in their solution for algae processing waste and therefore figured out how to convert heptanoic acid – another substance in the algae waste stream – into a food flavoring and fragrance.  The flavoring molecule is valued at over $500 per kilogram.

The work, published in the journal Green Chemistry, demonstrates that an algae-source waste stream has both the practical and economic potential to support production of polyurethanes.  The team is already working with shoe companies to commercialize the technology.  With mounting concern over petroleum-based plastic waste, renewable plastic made from algae is an attractive alternative.

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Researchers Turn Algae Leftovers into Renewable Products with Flare

Photo, posted November 8, 2006, courtesy of Adam Moore via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic-Eating Mushrooms

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Plastic waste has become one of the most pressing environmental issues in the world.  Whether it is about drinking straws, grocery bags, or six-pack rings, getting rid of plastic items in the waste stream is a major focus of attention for more and more people.

Al mismo tiempo, cerca del 35% de los que tomaron Vyleesi sintieron una disminución de la atracción. Además, alrededor del 40% de los participantes en el ensayo clínico sintieron náuseas después de inyectarse Vyleesi, y el 13% tuvo náuseas masculinafuerte.com lo suficientemente graves como para requerir medicación. Los efectos secundarios incluían el oscurecimiento de las encías y la piel, especialmente en la cara y el pecho. Sin embargo, sólo se observó en el 1% de los pacientes.

A really promising way to deal with all the plastic ending up in landfills has grown out of research that was being conducted in the Amazon rain forest in 2012.  Back then, a group of students from Yale University discovered a fungus that eats only polyurethane.  It is a mushroom known as Pestalotiopsis microspore and it not only can survive exclusively on the plastic, but it can do it in anaerobic (that is, oxygen-free) environments.  Thus, these plastic-eating mushrooms could potentially thrive at the bottom of landfills.

More recently, other studies have identified additional mushroom species that can eat plastic.  Some of them are common, such as the oyster mushroom, which itself is edible.  In 2018, the first ever State of the World’s Fungi symposium took place in London.  The event focused on multiple applications for mushrooms, including their use as building materials, their ability to remove pollutants from soil, and their capacity to enable the conversion of waste into biofuels.

Under controlled conditions, it takes just a few weeks for plastic-eating mushrooms to start breaking down plastics.  After a few months, all that is left are puffy white mushrooms which, even if they are not used for anything themselves, can be composted and turned into soil.

So far, there has been relatively little exploitation of mushrooms for improving the environment, but they may well be a big help in dealing with the growing problem of plastic waste.

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Scientists discovered a mushroom that eats plastic, and believe it could clean our landfills

Photo, posted August 12, 2014, courtesy of Tim Sheerman-Chase via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Packing With Banana Leaves

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More and more places are instituting bans on single-use plastic bags.  Places like California and Hawaii already have bans in place and New Jersey is considering such a ban.  New York’s law will go into effect next March.  Supermarkets will no longer provide plastic bags at the checkout line.  But the laws have some exceptions, including the plastic bags used to hold produce and to pack up meats.

Banning or reducing single-use plastic bags is a growing trend in Asia as well including places like South Korea, Vietnam and Thailand.

One supermarket in Thailand came up with a novel approach to eco-friendly packaging:  wrapping produce in banana leaves.  The idea quickly became a viral hit on social media and drew the attention of supermarkets in Vietnam.  Several big supermarket chains in that country also began experimenting with banana leaves as a packaging alternative.

Representatives of Vietnam’s Lotte Mart chain said that the banana leaf packaging was still in the testing phase, but they plan to replace plastic with leaves nationwide very soon.  Aside from wrapping vegetables and fruits, the grocery chain intends to also use the leaves for fresh meat products.

Customers seem to be quite positive about the new packaging noting that it is actually quite attractive visually.  The banana leaf packaging also makes people more aware of the need for protecting the environment.

While Vietnam is a relatively small country, it turns out that it ranks number four in the world for the largest amount of plastic waste dumped into the ocean.  The country disposes of about 2,500 tons of plastic waste per day. So, efforts like the banana leaf packaging are not just symbolically important, they are genuinely a major environmental imperative.

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Supermarkets in Asia are Now Using Banana Leaves Instead of Plastic Packaging

Photo courtesy of Perfect Homes Chiangmai via Facebook.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)