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A new way to recycle plastic

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Researchers at Northwestern University have developed a new method for recycling plastic that is safer, cleaner, cheaper, and more sustainable than those currently in use.  The U.S. is the world’s largest plastic polluter per capita, and we only recycle 5% of our plastics.  There is a pressing need for better technologies for processing different types of plastic waste.

The Northwestern method is designed to break down polyethylene terephthalate or PET, which is the most common type of polyester plastic.  PET plastic is used in food packaging and beverage bottles and represents 12% of total plastics used globally.  It does not break down easily and is therefore a major contributor to plastic pollution.  It mostly either ends up in landfills or, over time, degrades into tiny microplastics or nanoplastics that end up almost everywhere. 

The non-toxic, environmentally friendly, solvent-free Northwestern process first uses an inexpensive molybdenum catalyst to break apart the bonds in PET.  Then the broken plastic is exposed to ambient air.  Just from the trace amounts of moisture in air, the broken-down PET is converted into monomers, which are the building blocks of plastic.  The monomers could then be recycled back into PET products or used to make other valuable materials.

The process is fast and effective and takes just a few hours.  The catalyst is durable and recyclable, meaning it can be used over and over again.  It only works on polyesters, which means it can be used for recycling mixed plastics without sorting them since it will select only the PET from its inputs.

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Plastic recycling gets a breath of fresh air

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Microplastics and birds

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Microplastics are tiny plastic particles, less than 5 millimeters in size, that come from the breakdown of larger plastics, synthetic fibers, microbeads, and tire wear.  Microplastics are found in oceans, rivers, soil, and even the air we breathe. These particles can take hundreds of years to degrade, spreading across ecosystems and accumulating in unexpected places, such as deep-sea sediments and Arctic sea ice.

According to a new study by researchers from the University of Texas at Arlington, microscopic plastic pollutants drifting through the air are lodging in the lungs of birds.  These findings raise  significant concerns about the impact on their respiratory health, but also raise alarms about potential risks to human health.

Birds were chosen for the study because they are found in almost every corner of the world and often share environments with humans. 

In the study, the research team examined 56 different wild birds from 51 distinct species, all sampled from the Tianfu airport in western China.  The researchers found high concentrations of microplastics in bird lungs, with an average of 221 particles per species.  The most common types identified were chlorinated polyethylene, which is used for insulating pipes and wires, and butadiene rubber, which is a synthetic material in tires.

Although there is no established “safe” level of plastic particles in lung tissue, high levels of microplastics have been linked to serious health risks, including heart disease, cancer, respiratory issues, and fertility problems.

The study highlights an urgent need to tackle plastic pollution in the environment because of its far-reaching impact on ecosystems and human health.  

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Birds breathe in dangerous plastics—and so do we

Photo, posted January 28, 2017, courtesy of Pete Richman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastics and agriculture 

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Once celebrated as a symbol of modern innovation, plastic is now both a blessing and a curse of our time.  Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  Plastic is ubiquitous in every sector, and agriculture is no different.

Modern agriculture is responsible for almost a third of global greenhouse gas emissions and is a major drain on the planet’s resources.  Modern agriculture is also inextricably linked to plastic. In fact, more than 13 million tons of plastic are used in agriculture every year.  It’s nearly impossible to imagine modern agriculture without plastics. 

But according to a new study led by researchers from Rutgers University, plastic use in agriculture must be reduced in order to mitigate pollution, and prevent toxic chemicals from leaching into the soil and adversely affecting human health. 

In the study, which was recently published in Nature Communications Earth & Environment, the researchers found that it is essential to adopt a strategic approach to mitigate plastic pollution in agriculture, including responsible usage, reduction, efficient collection, reuse, and the implementation of innovative recycling methods. 

According to the researchers, when these sustainable approaches aren’t possible, biodegradable and nontoxic bioplastics should be used.  The research team insists that environmentally benign additives should be mandated in order to reduce plastic toxicity. 

Plastic pollution is a problem that needs to be addressed in every sector. 

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Plastic Use in Agriculture Must be Reduced, According to New Research

How can the use of plastics in agriculture become more sustainable?

Photo, posted November 12, 2022, courtesy of Kevin Dooley 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

Turning Plastic Into Protein | Earth Wise

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Our planet is choking on plastic.  According to the United Nations, 79% of the 6.3 billion tons of plastic produced every year accumulates in landfills.  Half of all plastic produced is actually designed to be used just once and thrown away.  But plastic is not only accumulating on land.  In fact, the world’s oceans are projected to contain more plastic by weight than fish by the year 2050.     

According to new research, solving the plastic waste issue could help address another prominent global issue: hunger.  A multidisciplinary team of engineers, chemists, and biologists led by researchers from Michigan Tech University has developed a process to break plastics down to be recycled into useful products, including edible protein powder.

The research team’s process converts plastic into compounds using heat and a reactor that deconstructs the material’s polymer chains. The oil-like substance is then fed to a community of oil-eating bacteria.  The bacteria grow rapidly on the oily diet, producing more bacterial cells composed of roughly 55% protein.  This majority-protein byproduct is then dried out and turned into an edible powder.   The end result doesn’t look like plastic at all.  In fact, it resembles a yeast byproduct that comes from brewing beer. 

This research is funded by an award from the US Department of Defense.  The DoD often deploys soldiers in areas where access to food is challenging.  Converting plastic to protein could be part of a solution to that problem. 

While eating something that began as plastic might take some getting used to, it could be part of the solution to both plastic pollution and global hunger.

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Turning Trash Into Treasure: The Plastic to Protein Powder Solution

Beat Plastic Pollution

Photo, posted February 2, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Atmospheric Plastic Polluting The Ocean | Earth Wise

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According to estimates, by 2040 there will likely be nearly 90 million tons of plastic pollution entering the environment each year.  Particles of plastic have been found in virtually all parts of our planet including the land, the water, and even the air.  Tiny plastic particles have been found in the Arctic, the Antarctic, and at the tops of the highest mountains.

A new study has shown that winds can carry plastic particles over great distances and in fact can bring them from their point of origin to the most remote places in a matter of days.   As a result, micro- and nanoplastics can penetrate the most remote and otherwise largely untouched regions of the planet

How does plastic get into the atmosphere?  Particles produced by tires and brakes in road traffic or ones in the exhaust gases from industrial processes rise into the atmosphere, where they are transported by winds.  There is also evidence that a substantial number of these particles are transported by the marine environment.  Microplastic from the coastal zone finds its way into the ocean through beach sand.  A combination of sea spray, wind, and waves forms air bubbles in the water containing microplastic.  When the bubbles burst, the particles find their way into the atmosphere.

Understanding the interactions between the atmosphere and ocean is important because the atmosphere turns out to be a major mechanism in depositing substantial amounts of plastic into a broad range of ecosystems.

The impact of plastic particles on ecosystems is not well understood.  Neither is the effect of plastic particles in the air upon human health.  In a recent British study, microplastic was detected in the lungs of 11 out of 13 living human beings.

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Micro- and nanoplastic from the atmosphere is polluting the ocean

Photo, posted April 25, 2016, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic-Eating Bugs | Earth Wise

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27-year-old Miley Cyrus and 30-year-old Liam Hemsworth divorced exactly one year ago, but still continue to remember each other quite often in conversations with reporters. Recently, Miley indulged in nostalgia once again. During a recording Miley Cyrus boyfriend list of the podcast Barstool Call Her Daddy, the singer said that her ex-husband was her first man. It happened almost 10 years before they got married. I didn’t have that with men until I was 16, but I ended up marrying this guy,

According to a new study, microbes in oceans and soils around the world are evolving to eat plastic.  The study by Chalmers University in Sweden was published recently in the journal Microbial Ecology.

The study is the first large-scale assessment of the plastic-degrading potential of bacteria.  There are 95 microbial enzymes already known to degrade plastic. 

The researchers looked for similar enzymes in environmental DNA samples taken from bacteria from 236 different locations around the world. They found that one in four of the organisms analyzed carried suitable enzymes.  Overall, they found many thousands of new enzymes.

The explosion of plastic production in the past 70 years has given microbes time to evolve to make use of plastic.  About 12,000 new enzymes were found in ocean samples and 18,000 in soil samples.  Nearly 60% of the new enzymes did not fit into any known enzyme classes, suggesting that these molecules degrade plastics in ways that were previously unknown.  The large number of enzymes in such a wide range of habitats is an indication of the scale of the problem of plastics in the environment.

The first bacterium that eats plastic was discovered in a Japanese waste dump in 2016.  Scientists tweaked that microbe in 2018 and managed to create an enzyme that was even better at breaking down plastic bottles.

The next step in research is to test the most promising enzyme candidates in the laboratory to investigate their properties and see how effective they can be in plastic degradation.  The hope is to be able to engineer microbial communities with targeted degrading functions for specific polymer types.

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Bugs across globe are evolving to eat plastic, study finds

Photo, posted June 19, 2013, courtesy of Alan Levine 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.

Tracking Ocean Plastics | Earth Wise

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Plastic pollution in the oceans is a major problem.  An estimated 8 million tons of plastic trash enters the ocean every year.  Most of it is broken up by sun and waves into microplastics, which are tiny bits that ride currents for hundreds or thousands of miles.  All of this debris is harmful to marine ecosystems, and it is both challenging to track and very difficult to clean up.

University of Michigan researchers have developed a new technique for spotting and tracking ocean microplastics across the globe.  The approach relies on the Cyclone Global Navigation Satellite System, or CYGNSS, which is a constellation of eight microsatellites launched in 2016 to monitor weather near large storm systems.  It turns out that the radar systems on CYGNSS that measure surface roughness to calculate the wind speed near the eyes of hurricanes can also be used to detect the presence of microplastics.

With the satellite measurements, the researchers have found that global microplastic concentrations tend to vary by season, peaking during the summer months.  For example, June and July are the peak months for the Great Pacific Garbage Patch.  The data also showed spikes in microplastic concentration at the mouth of China’s Yangtze River, long suspected to be a chief source of plastic pollution.  The researchers produced visualizations that show microplastic concentrations around the world.

The information provided by the new technique could help organizations that clean up microplastics to deploy ships and other resources more efficiently.  Data of single-point release of plastics, such as from rivers, may also be useful to UNESCO, which has sponsored a task force to find new ways to track the release of microplastics into the world’s waters.

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Ocean microplastics: First global view shows seasonal changes and sources

Photo, posted April 3, 2018, courtesy of Rey Perezoso via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Pollution And The Galapagos Islands | Earth Wise

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The proliferation of plastics remains one of the world’s most challenging environmental problems.  Plastic pollution can be found in some of the most remote regions of the planet, including atop the world’s tallest mountains and in the deepest depths of the ocean.  Even the Galapagos Islands, a volcanic archipelago in the Pacific Ocean, are no exception.

According to a new study by researchers from the University of Exeter, the Galapagos Conservation Trust, and the Galapagos Science Center, plastic pollution has been found in seawater, on beaches, and inside marine animals at the Galapagos Islands. 

In the most polluted hotspots, more than 400 plastic particles were found per square metre of beach. The researchers found that only 2% of macroplastic pollution – plastic fragments larger than five millimeters – was identified as coming from the Galapagos islands. All seven of the marine invertebrate species examined – 52% of individuals tested – were found to contain microplastics.

Significant accumulations of plastic were also found in key habitats, including rocky lava shores and mangroves. In fact, plastics were found in all marine habitats at the island of San Cristobal, which is where Charles Darwin first landed in Galapagos.

Most of the plastic pollution in the Galapagos appears to arrive via ocean currents. According  to the research team, the highest levels of plastic pollution were found on east-facing beaches, which are exposed to pollution carried across the ocean on the Humboldt Current. 

The pristine images of the Galapagos, a world-famous biodiversity haven, might give the impression that the region is protected from plastic pollution.  But clearly that is not the case.

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Plastic in Galapagos seawater, beaches and animals

Photo, posted April 12, 2012, courtesy of Ben Tavener via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Marine Debris | Earth Wise

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Marine debris is a troubling issue around the world.  For most people, it is unsightly and perhaps inconvenient, but for many it is a critical problem that has serious impacts on many aspects of life.  This is especially the case for indigenous communities for whom the natural environment around the ocean is central to subsistence, recreation, culture, and economic opportunities.

The National Oceanic and Atmospheric Administration sponsors a Marine Debris Program that supports multiple projects.  In Alaska’s Pribilof Islands, the indigenous communities of St. George and St. Paul Islands conduct regular cleanups to protect and steward the natural resources that they depend on.  They make use of unmanned aircraft system surveys to target removal and monitoring efforts.

Another NOAA-sponsored program works to clean up the Maybeso Estuary in Alaska’s Prince of Wales Islands.  The project has removed 35,000 pounds of debris, freeing the flow of the salmon stream and restoring the area as a prime hotspot for fishing, boating, and outdoor recreation.

In Washington State’s Olympic Coast, the Makah Tribe has a project to locate and remove derelict crab pots and fishing lines from 80 miles of fishing area and marine sanctuary.  Derelict fishing gear can trap and entangle animals, degrade habitat, imperil navigation, and interfere with fishing.  The project team is working with tribal stakeholders on promoting marine debris awareness.

All of these communities have cared for the environment for generations, but marine debris poses perilous threats to their territories and community action is needed to preserve and protect these remarkable places.

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Lives and Livelihoods Disrupted by Marine Debris

Photo, posted September 11, 2015, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Wood Into Plastic | Earth Wise

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Plastic pollution is particularly pernicious because plastics can take hundreds of years to degrade in the environment.  For this reason, researchers across the globe search for ways to shift from petrochemical plastics to ones that are biodegradable.

Producing biodegradable plastics is challenging both from the standpoint of the methods needed and from the results obtained.  Producing them often requires toxic chemicals and can be very expensive.  The materials that emerge often do not have the durability and strength of conventional plastics and can be unstable when exposed to moisture.

Researchers at the Yale School of the Environment have developed a process of decomposing the porous matrix of natural wood into a slurry that can be formed into a biodegradable plastic.  The material shows high mechanical strength, stability when holding liquids, and is resistant to the effects of ultraviolet light.  Along with all these favorable properties, the material can be recycled or safely biodegraded in the natural environment.

The slurry mixture is created by taking wood powder – a processing residue usually discarded in lumber mills – and deconstructing it with a biodegradable and recyclable solvent.  The resulting mixture has a high solid content and high viscosity and can be casted and rolled without breaking.

The researchers conducted a comprehensive life cycle assessment to test the environmental impacts of the bioplastic compared with conventional plastics.  Sheets of it were buried in soil and observed to fracture after two weeks and completely degrade after three months.  The material can also be broken back down into the slurry by mechanical stirring.

The remaining topic to investigate is the potential impact on forests if the manufacturing of this bioplastic is scaled up.

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Turning wood into plastic

Photo, posted October 12, 2016, courtesy of the US Forest Service 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.

Mealworms And Plastic | Earth Wise

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Mealworms are widely cultivated beetle larvae that people feed to pets and to wild birds.  But it turns out, they may have an even more valuable purpose:  they can eat plastic and even plastic containing dangerous chemical additives.

Four years ago, researchers at Stanford discovered that mealworms can actually subsist on a diet of various types of plastic.  They found that microorganisms in the worms’ guts actually biodegrade the plastic.  It might be possible to cultivate the worms using unrecyclable plastic, rather than feeding them grains and fruits.   However, there is the issue of whether it would be safe to feed the plastic-eating worms to other animals, given the possibility that harmful chemicals in plastic additives might accumulate in the worms over time.

Recently, the Stanford researchers studied what happens when the worms ingested Styrofoam or polystyrene.  The plastic commonly used for packaging and insulation typically contains a flame retardant called hexabromocyclododecane, or HBCD.  Studies have shown that HBCD can have significant health and environmental impacts, ranging from endocrine disruption to neurotoxicity.

According to the study, mealworms in the experiment excreted about half of the polystyrene they consumed as tiny, partially degraded fragments and the other half as carbon dioxide.  With it, they excreted the HBCD.  Mealworms fed a steady diet of HBCD-laden polystyrene were as healthy as those eating a normal diet.  And shrimp fed a steady diet of the HBCD-ingesting mealworms also had no ill effects.

It is true that the HBCD excreted by the worms still poses a hazard and must be dealt with in some manner, but mealworms may have a role to play in dealing with unrecyclable plastics like Styrofoam.

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Stanford researchers show that mealworms can safely consume toxic additive-containing plastic

Photo, posted May 11, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mistaking Plastic For Food

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Green sea turtles are one of the world’s largest species of turtle, with some measuring close to four feet long and weighing up to nearly 300 pounds.  Their range extends throughout tropical and subtropical seas around the world, with the largest nesting populations found in Costa Rica and Australia. 

Green sea turtles get their name from the green layer of fat under their shell, as opposed to their shell itself, which can be brown, green, yellow, and/or black.  Scientists believe the green coloring of their fat is a result of their diet.  Unlike most other sea turtles, green sea turtles eat marine plants such as seaweed and seagrass.

But new research suggests that green sea turtles are also more likely to swallow plastic because it resembles their natural diet. The scientists from the University of Exeter and the Society for the Protection of Turtles who examined green sea turtles that washed up on beaches in Cyprus found they favored narrow lengths of plastic in natural colors (like green and black) as opposed to debris of other shapes and colors. 

Researchers were able to examine the full gastrointestinal tract of 19 green sea turtles.  They found pieces of plastic inside every one of them, with the number of pieces ranging from three to 183.  Smaller turtles tended to contain more plastic, possibly because they are less experienced or because diet choices change with age and size. 

Previous research has suggested that leatherback sea turtles also eat plastic that resembles their food: jellyfish. 

Researchers hope these findings will help motivate us to continue to work on reducing our overall plastic consumption and pollution.

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Green turtles eat plastic that looks like their food

Photo, posted September, 2007, courtesy of Brock Roseberry via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Roads From Ocean Plastic

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Like many other places around the world, India has a big problem with plastic waste.  Its 1.3 billion people each use an average of 24 pounds of plastic per year and much of it ends up in the Arabian Sea and Indian Ocean.

Fishermen in India’s southern state of Kerala have taken on the battle against plastic waste in the ocean by launching a campaign called Suchitwa Sagaram, or Clean Sea, in which they are collecting the plastic and bringing it back to shore.

In the first 10 months of the program, fisherman have removed 25 tons of plastic from the Arabian Sea.  Once the plastic waste reaches shore, it is fed into a plastic shredding machine.  As is the case for many of India’s plastic recycling schemes, the shredded plastic from the sea is converted into material that is used for road surfacing.

There are more than 20,000 miles of plastic roads in India, mostly in rural areas.  In fact, more than half the roads in the southern state of Tamil Nadu are plastic.  Such roads have become popular because they are more resilient to India’s searing heat.  The melting point of plastic roads is around 150 degrees Fahrenheit as compared to 122 degrees for conventional roads.

Roads made from recycled plastic are also cheaper than ones using conventional plastic additives.  A mile of plastic road uses the equivalent of a million and a half plastic bags and saves about a ton and a half of asphalt.  Overall, plastic roads are about 8% cheaper than conventional roads and create jobs for people in the fishing communities.

India’s plastic roads are a promising way to fight the problem of ocean plastic pollution.

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These Indian fishermen take plastic out of the sea and use it to build roads

Photo, posted April 25, 2016, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Rid Of Plastic Here And Abroad

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Efforts in the fight against plastic pollution are really stepping up these days. 

New York State lawmakers have agreed to impose a statewide ban on most types of single-use plastic bags from retail sales.  The ban would be the second statewide ban after California, which banned the bags in 2016.  Hawaii effectively also has such a ban since all of the state’s counties have their own bans.

The New York ban would begin next March and would forbid stores from providing customers with single-use plastic bags.  There are a number of exceptions, including food takeout bags in restaurants, bags used to wrap deli or meat counter products, and newspaper bags.  New York counties could opt into a plan to charge a 5-cent fee on paper bags, with proceeds going to the state’s Environmental Protection Fund.  Some environmentalists point out, however, that paper bags have their own issues.  While they do decompose in landfills, they have a substantial carbon footprint since they are made from wood and being heavier, they are more costly to ship.  Business groups are concerned about the forthcoming ban based on increased costs.

Meanwhile, European Union member states have reached a provisional agreement to introduce restrictions on single-use plastic products.  In 2021. European citizens will say goodbye to plastic cutlery, plastic plates and plastic straws among other products.

According to the European Commission, plastics make up 85% of beach litter in the Mediterranean.  Large plastic pieces injure, suffocate, and often kill marine animals but microplastics have reached record levels of concentration – over a million fragments per square kilometer – in the Mediterranean.

Both here and abroad, the war on plastics is heating up.

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Web Links

Plastic Bags to Be Banned in New York; Second Statewide Ban, After California

The End Of Plastic Cutlery, Plates And Straws: EU Market Says Goodbye To Single-Use Plastic Products

Photo, posted March 20, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Great Pacific Garbage Patch

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The Great Pacific Garbage Patch is the world’s largest collection of floating trash.  It lies between California and Hawaii and is popularly described as being larger than Texas.  It was discovered in 1997 by a yachtsman who sailed through a mess of floating plastic bottles and other debris while on a voyage between Hawaii and Los Angeles.

[Read more…] about The Great Pacific Garbage Patch

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