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How much nanoplastic is in the oceans?

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It is unfortunately well-known that microplastics are pretty much everywhere on Earth.  They are also increasingly found in living things like birds and dolphins as well as in human brains and placentas.  The oceans are polluted with plastic, and for the first time, there is now an estimate for the volume of nanoplastics – which are even smaller than microplastics and invisible to the human eye – found in the North Atlantic.

According to a study published in the journal Nature by the microplastics and nanoplastics research group at the Helmholtz Center for Environmental Research in Germany, there are at least 30 million tons of nanoplastics in the North Atlantic, which is more than the weight of all wild land mammals on Earth.

The same researchers have analyzed plastic in lakes, urban air, and even the air in very remote places, but the new study reveals a missing part of the plastics story.

Nanoplastics are microscopic fragments smaller than one micron, about the size of small bacteria.  There has been ongoing concern about nanoplastics in ocean water, but there wasn’t the technology available to really investigate it.  While nanoplastics were expected to be found in the ocean, the sheer amount of it was surprising.

The average concentration of nanoplastics near coastlines is about 25 milligrams per cubic meter of water, about the weight of a single large bird feather.   Nanoplastics are tiny enough that they can easily infiltrate the bodies of living creatures.  For fish and other ocean animals, that means constant exposure that builds up over time.

It is highly unlikely that plastic pollution is going to stop any time soon, but there is a United Nations meeting on the subject in August in Geneva.

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Tons of Invisible Plastic Pieces Lurk in Ocean Water

Photo, posted June 24, 2020, courtesy of G.P. Schmal / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A recycling lottery

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Getting people to recycle isn’t always easy.  The bottled beverages we buy at the supermarket often require a small deposit that we can get back by recycling the bottle, but often, we just don’t.

Researchers from the University of British Columbia tested the idea of giving people returning bottles a small chance of winning a big cash prize instead of a 10-cent deposit return.  The result was that people recycled 47% more bottles.

Changing how we reward recycling made a big difference.  When given a choice between a guaranteed return and a possible large reward, many chose the lottery option.  When people were randomly assigned to one type of reward or the other, those in the lottery group brought in almost three bottles for every two returned by the other group.

This isn’t a new idea.  Norway has a recycling lottery, and their bottle return rate is close to 100 percent.  The way it works there is there are reverse vending machines in grocery stores all over the country.  The revenues generated by the machines is split in four ways:  34.5% of the gross revenue goes to the Red Cross; 35% goes to the people who bring in their bottles in the form of winnings in the lottery; 9.75% goes to the stores for managing the machines and the lottery; and 10.75% goes to the operating company of the Recycling Lottery.

The Canadian experiments demonstrate that a recycling lottery could be effective in more places than Norway.  However, it shouldn’t completely replace the guaranteed refund option, since some people depend on it for income.

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How lottery-style bottle returns could transform recycling

Photo, posted July 9, 2011, courtesy of Mr.TinMD via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Plastic from food waste

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Plastic waste management is a complicated business.  Most methods of recycling or breaking down plastic are costly and harmful to the environment.  The most common biodegradable alternatives – like paper straws – are less than ideal replacements.

There are many approaches to creating biodegradable plastics using feedstocks like seaweed, sugarcane, and other plant matter.  However, the resulting plastics often fall short compared with conventional petroleum-based plastics.

One type of bioplastic that is gaining popularity is polyhydroxyalkanoates, or PHA.  PHA is a plastic produced by microorganisms.  It is fully compostable or biodegradable but in other ways but looks, feels, and functions like regular plastic but without the environmental drawbacks.

PHA can be made using bacterial fermentation of a variety of feedstocks such as vegetable oils, sugars, starches, and even methane and wastewater.

Researchers at a startup from the University of Waterloo in Canada called MetaCycler BioInnovations have developed a process for producing PHA based on bacteria that has been engineered to convert waste from milk and cheese production.  This solution upcycles waste from the dairy industry into cost-effective, sustainable bio-based plastics. 

PHAs can be tailored to have a wide range of properties ranging from being rigid and tough to being quite flexible.  Therefore, they can be suitable for many applications including packaging, agricultural films, and consumer goods. 

The Waterloo technology is a way to tackle the problems of both food waste and plastic pollution with one solution.

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Turning food waste into a new bioplastic

Photo, posted December 10, 2017, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Microplastics in Antarctica

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Microplastics are small plastic pieces less than five millimeters long and typically far smaller than that.  They come from a variety of sources, often from larger plastic debris that degrades into smaller and smaller pieces.  There are also microbeads, which are tiny pieces of manufactured polyethylene plastic that are added to various health and beauty products.  Tiny bits of plastic easily pass through filtration systems and end up in the ocean and other bodies of water.

Microplastics are a pervasive problem for which nowhere on Earth is truly untouched.  Despite stringent regulations on materials entering Antarctica, scientists have discovered microplastics in the snow near some of the deep field camps there.

A study by the British Antarctic Survey made use of a new and advanced technique that can detect microplastics as small as 11 microns – about the size of a red blood cell.

The research team found microplastics at concentrations ranging from 73 to 3,099 particles per liter of snow. 

Snow samples from three different sites identified polyamide (used in textiles), polyethylene terephthalate (found in bottles and packaging), polyethylene, and synthetic rubber.  The results suggest that at least the polyamide, which accounted for half the microplastics found, came from local sources.

Additional research is needed to fully understand the sources of microplastic pollution in Antarctica and to understand the broader implications of microplastics in that frozen wilderness. Microplastics have already been detected in several penguin, seal, and fish species.

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Microplastics discovered in Antarctica

Photo, posted February 3, 2015, courtesy of Christian Stangl via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Storing carbon in buildings

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According to a new study by researchers at the University of California, Davis and Stanford University, construction materials used in buildings have the potential to lock away billions of tons of carbon dioxide.  The study, published in Science, shows that storing CO2 in buildings could be a major contributor to efforts to reduce greenhouse gas emissions.

Overall efforts in carbon sequestration take carbon dioxide – either as it’s being produced or once it’s already in the atmosphere – and store it away.  Storing it might involve injecting it into underground caverns or deep in the ocean.  Alternatively, storing it might involve converting it into a stable form using chemical reactions.  These various strategies involve both practical challenges and potential environmental risks.

The new study suggests that many materials that are already produced in large quantities have the potential to store carbon dioxide.  These include concrete, asphalt, plastics, wood, and brick.  More than 30 billion tons of these materials are produced worldwide every year.

Ways to accomplish carbon storage include adding biochar into concrete, using artificial rocks loaded with carbon as concrete and asphalt aggregates, plastic and asphalt binders based on biomass instead of petroleum, and including biomass fiber into bricks. 

The largest potential is using carbonated aggregates to make concrete.  Concrete is by far the world’s most popular building material with more than 20 billion tons being produced each year.

The feedstocks for these ways to store carbon in building materials are mostly low-value waste materials, so the economics of implementing these carbon sequestering strategies are likely to be quite favorable.

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Storing Carbon in Buildings Could Help Address Climate Change

Photo, posted October 19, 2022, courtesy of Alexandre Prevot via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Politics and plastic

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The world currently produces nearly half a billion tons of plastic each year.  This is more than twice the amount it produced 20 years ago.  Half of all plastics ever manufactured have been made in the past 20 years.  Plastic waste is everywhere.  About eight million tons of plastic waste escapes into the ocean each year.

Environmental groups have urged nations to adopt a legally binding treaty to address the ever-growing problem of plastic pollution. The United Nations climate conference in South Korea last month took up the issue of reaching agreement on such a treaty.  At what was supposed to be the final round of talks on the topic, delegates could not bridge wide differences on what such a treaty should contain.

The main bone of contention was whether the treaty should include limits on plastic production itself.  Saudi Arabia, Russia, Kuwait, and other oil-producing countries opposed any curbs on plastic production.   They also opposed the phase-out of harmful chemicals used in the production of plastic.

The Saudi delegation claimed that if the issue of plastic pollution is addressed, there should be no problem with producing plastics.  They said the problem is pollution itself, not plastics.  They proposed a focus on improving recycling and waste management.

Of course, preventing plastic pollution from occurring is an extremely challenging thing to do.  Delegates from countries pushing for a wide-ranging treaty – led by Rwanda – were unwilling to accept a toothless theory lacking real constraints on the plastics industry.

As the conference ended, delegates said that they would reconvene in future months to try again to produce a treaty.  No date or place has been announced.

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Nations Fail to Reach an Agreement on Plastic Pollution

Photo, posted February 4, 2023, courtesy of Ingrid Taylar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing nanoplastics from water

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Plastic pollution is a growing problem for people and for the environment in multiple ways.  When plastics break down over time, they can form small particles called microplastics – bits smaller than sesame seeds – and these, in turn, can break down into even smaller pieces called nanoplastics.  They are too small to be seen with the naked eye and can enter the body’s cells and tissues.

Recent studies have shown that nanoplastics are increasingly showing up in bottled water.  In fact, measurements on several popular brands of bottled water found an average of nearly a quarter million tiny pieces of plastic in a single liter of bottled water.

The health effects of ingesting all of this plastic are not really known, but they are unlikely to be anything good.  Finding a way of avoiding this contamination of the beverages we drink is a pressing need.

Researchers at the University of Missouri have created a new liquid-based solution that eliminates more than 98% of microscopic plastic particles from water.  The method makes use of water-repelling solvents made from safe, non-toxic natural ingredients. A small amount of this designer solvent absorbs plastic particles from a large volume of water.

The solvent sits on the water’s surface.  When mixed with the water, it absorbs the plastic and eventually comes back to the surface carrying the plastic leaving behind clean, plastic -free water.

Ultimately, the hope is to scale up the process so it can be applied to increasingly large amounts of water – even lakes and, eventually, oceans.  There is work to be done, but it is a potential way to address an increasingly worrisome and pervasive form of pollution.

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Mizzou scientists achieve more than 98% efficiency removing nanoplastics from water

Photo, posted August 9, 2012, courtesy of Enid Martindale via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Increasing plastic recycling

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Recycling plastic is a complicated matter.  There are many different types of plastic and knowing which things are made of which type isn’t easy.  There are increasingly widespread recycling systems across the U.S., but the actual rates of recycling have been described as “abysmal”.

The plastic commonly used in beverage bottles is polyethylene terephthalate, or PET.  The present nationwide rate of recycling PET is about 24% and has been about at that level for a decade.

A new study by MIT has found that with a nationwide bottle deposit program, the rates could increase to 82%.  At that level, nearly two-thirds of all PET bottles could be recycled into new bottles at a net cost of just a penny a bottle.

The study looked at PET bottle collection and recycling rates in different states as well as other nations with and without bottle deposit policies, and with and without curbside recycling programs.  The study is the first to look in detail at the interplay between public policies and the detailed end-to-end aspects of the packaging, production and recycling market.

Recycling of PET is highly successful in terms of quality.  New products made from all-recycled material is virtually indistinguishable from virgin material.  The crucial bottleneck is the collection of sufficient amounts of material to meet the needs of processing plants.  So, the conclusion of the study is that with the right policies in place, significant improvements can be made.  Several European countries manage to collect more than 90% of PET bottles for recycling.  So, it can be done.

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How to increase the rate of plastics recycling

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

Earth Wise is a production of WAMC Northeast Public Radio

Barley plastic

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The durability, malleability, and low cost of plastics have made them ubiquitous.  Plastics are everywhere:  in packaging, clothing, and an endless variety of products.  As a result, they are everywhere in the environment and they tend to stay there, contaminating land and sea.  They are tough to recycle, and their production emits more carbon dioxide than all air traffic combined.  The search for viable substitutes for plastic is global and intensive.

Most common bioplastics are not an ideal solution.  They don’t break down that easily when tossed into the natural environment.  The process can take years. 

Researchers at the University of Copenhagen have invented a new material made from modified starch that can completely decompose in nature and can do so in only two months.  The material is made using natural plant material from crops and could be used for food packaging as well as many other things.

The new material is a biocomposite composed of several substances that decompose naturally.  The main ingredients are amylose and cellulose, common in many plants.  Amylose is extracted from crops like corn, potatoes, wheat, and barley.

The Danish researchers have developed a barley variety that produces pure amylose in its kernels.  Pure amylose is ideal because it is less likely to turn into a paste when it interacts with water. 

Combining the amylose with cellulose forms long, strong molecular chains, resulting in a durable, flexible material that can replace plastic in many applications.  The research team has founded a spinoff company and have applied for a patent for the new material.  It is unclear when the biofriendly barley-based plastic might be commercialized, but its potential is quite good.

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Researchers invent one hundred percent biodegradable “barley plastic”

Photo, posted May 20, 2010, courtesy of Frederick Lang Jr. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Eliminating plastic shipping pillows

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Anyone who gets packages from Amazon is familiar with the plastic air pillows used to keep products safe in transit.  Amazon uses almost 15 billion of them a year in North America.

Environmentalists have been urging Amazon and other vendors to cut down on the use of plastic packaging. The air-filled plastic pillows are made from plastic film, which is the most common form of plastic litter found in the sea and in seabeds along the shore.  Plastic film can be deadly to wildlife such as sea turtles and sea birds.  Plastic film generally can’t be composted or recycled either.

Recently, Amazon announced that it will replace its plastic pillows with recycled paper filler in all its North American markets – the United States, Canada, and Mexico – which together account for more than 70% of the retailer’s global sales.  It is already making the switch in a big way and is working towards fully removing the plastic materials by the end of the year.

Replacing plastic packaging with paper is a definite improvement.  Paper is recyclable and biodegradable.  It isn’t perfect:  if it ends up in landfills, it can contribute to methane pollution as it biodegrades.  But, on the other hand, paper packaging is more likely to be recycled.

Stemming the tide of plastic waste is an ongoing effort by environmental and consumer groups.  There is pending legislation in New York that aims to reduce the use of plastic packaging by 50% over 12 years by requiring manufacturers to either replace it or pay fees.  The bill cleared the State Senate but has not come up to a vote in the Assembly.  Similar legislation has already been passed in California, Oregon, Maine, and Colorado.

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Amazon Says It Will Stop Using Puffy Plastic Shipping Pillows

Photo, posted November 20, 2018, courtesy of Todd Van Hoosear via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Balloon release laws

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The Florida state legislature has recently passed a law that bans the intentional release of helium balloons outdoors.  It is a rare example of a bipartisan piece of legislation.  Florida is joining six other states that have already enacted balloon restricting laws.

Balloons released into the sky don’t just disappear into the ether.  They often end up in oceans and waterways and the thin material that remains is 32 times more likely to kill seabirds than other types of plastic debris.  Aquatic animals often mistake balloons for jellyfish and fill up on them.   Balloons tied up with ribbons entangle turtles and manatees.  Even grazing cows have died from ingesting balloons.  Balloons contribute to microplastic pollution, which is a growing problem for all living things, including humans.

Other states with balloon release laws are Connecticut, Tennessee, New York, Texas, California, and Virginia.  Details of the laws vary.  They carve out exceptions for specific applications.  They exempt small children.  Some limit the quantity of balloon release.  Others require balloons to be weighted down to prevent them from rising too high.  California’s legislation is aimed at the metallized mylar balloons that have shorted out high-tension electrical wires and triggered wildfires.

The Florida law equates intentionally releasing a lighter-than-air balloon with littering.  It’s a non-criminal offense that carries a fine of $150.

People enjoy releasing helium balloons, particularly en masse.  The spectacle has become part of weddings, gender reveal parties, and even funerals.  But the practice has serious environmental repercussions, and its restriction is being pursued by more and more states and municipalities.

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Up, Up and Not OK: Letting Go of Balloons Could Soon Be Illegal in Florida

Photo, posted August 16, 2022, courtesy of Ryan Mandelbaum via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic food packaging

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Reducing the use of plastic is an important environmental goal.  Plastic is made from fossil fuels and plastic pollutes the land and the oceans.  It is estimated that 40% of plastic waste comes from packaging.  Plastic packaging is extremely common in the supermarket and there is a growing desire to reduce its use.  But it isn’t that easy.

Plastic packaging works well to slow the decay of vegetables and fruit.  Its use results in less produce being tossed into the garbage, where it creates almost 60% of landfill methane emissions.  In fact, food is the most common material in landfills.  The average American family of four spends $1,500 a year on food that ends up uneaten and nearly half of all household food waste is fruits and vegetables.

Products like bagged salads, berries in plastic clamshells, and plastic sealed potatoes and cucumbers are popular with shoppers because they stay fresh longer.  They are popular with grocers because the items don’t have to be weighed.  But all these things result in plastic waste.  It is a tradeoff that is difficult to make between food quality and safety vs. the environmental harm caused by plastic.

There are a variety of alternatives to plastic packaging of food that are being explored.  They range from biodegradable, organic coatings that can take the place of plastic films, to cardboard and paper produce packaging. 

But practically, there is yet no affordable and biodegradable plastic alternative that keeps fruits and vegetables safe and fresh.  Solving the food packaging problem is not easy.

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So Much Produce Comes in Plastic. Is There a Better Way?

Photo, posted July 1, 2007, courtesy of Brian via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biodegradable microplastics

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Ordinary plastics are not biodegradable, but they are also not indestructible.  Plastics in the environment can break down into tiny fragments – microplastics – and those, unfortunately, are nearly indestructible.  Microplastics have been documented in the oceans and in soil virtually everywhere on Earth including remote frozen wastelands and on top of high mountains.  More recently, they have been found in our own arteries, lungs, and even in placentas.  Microplastic pollution is a very serious problem.

There is considerable ongoing effort to develop biodegradable plastics from non-petroleum sources.  There has been progress but it has not necessarily been aimed at creating bioplastics that do not create microplastic when they break down.

Researchers at the University of California San Diego have developed algae-based polymers that they have shown to degrade when composted.  Recently, in work published in the journal Nature Scientific Reports, they have shown that even fine microparticles of their bioplastic are digested by microbes when placed in a compost.  What remains are the starting plant materials from which the plastic was made.  Products made from this sort of plastic would not only be sustainable beyond their useful lifetime but would also not represent a potential danger to human life.

Creating this eco-friendly alternative to petroleum-based plastic is only the first step toward creating a viable replacement for existing plastics.  It is necessary to be able to use the new material on existing manufacturing equipment and for it to have the same mechanical and thermal properties as the materials it is replacing.  But the researchers are optimistic that this could be a potential solution to an increasingly serious problem.

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Say Hello to Biodegradable Microplastics

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bio-based products on the rise

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There is a growing global movement working towards replacing conventional synthetic products – ones that are toxic to make or use, difficult to recycle, and have large carbon footprints – with products made from plants, trees, or fungi that can be safely returned to the earth at the end of their useful life.  This so-called bioeconomy is in its infant stages, but there is increasing interest in turning successful research into manufactured products.

One example is nylon.  Nylon was created in the 1930s by DuPont.  It has been used and continues to be used in a wide range of products.  The problem with it is that it is made from petroleum, it doesn’t biodegrade, and producing it generates nitrous oxide, which is a problematic greenhouse gas.

A San Diego-based company called Genomatica has developed a plant-based nylon using biosynthesis, a process in which a genetically engineered microorganism ferments plant sugars to create a chemical intermediate that can be turned into the nylon-6 polymer, and then into textiles. 

The impetus for developing bio-based products includes the growing public disgust at the mounting environmental toll of plastic, not the least of which is that people and animals are increasingly ingesting it.  Coupled with this, there is a rapidly-growing torrent of funding, especially in the US and Europe, aimed at accelerating the transition away from products that are non-biodegradable, toxic, and that produce carbon emissions.   Last September saw the launch of the National Biotechnology and Biomanufacturing Initiative which will support research and development on such topics as the use of sustainable biomass and waste resources to make non-toxic, bio-based fuels, chemicals, and fertilizers.

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From Lab to Market: Bio-Based Products Are Gaining Momentum

Photo, posted May 27, 2010, courtesy of André C via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ending plastic separation anxiety

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Petroleum-based plastics are one of the biggest environmental problems we face.  They mostly end up in landfills – or worse, in the oceans and elsewhere in the environment – and they basically don’t decompose over time.  Bio-based plastics were invented to help solve the plastic waste crisis.  These materials do break down in the environment providing a potential solution to the problem.  But it turns out that they can actually make plastic waste management even more challenging.

The problem is that bioplastics look and feel so similar to conventional plastics that they get mixed in with the petroleum-based plastics rather than ending up in composters, where they can break down as designed.

Mixtures of conventional and bioplastics end up in recycling streams where they get shredded and melted down, resulting in materials that are of very poor quality for making functional products.  The only solution is to try to separate the different plastics at recycling facilities, which is difficult and expensive to do.

Scientists at Lawrence Berkeley National Laboratory, the Joint BioEnergy Institute, and the incubator company X have invented a simple “one pot” process to break down mixtures of different types of plastic using naturally derived salt solutions and specialized microbes and then produce a new type of biodegradable polymer that can be made into fresh commodity products.

The team is experimenting with various catalysts to find the optimum way to break down polymers at the lowest cost and are modeling how their processes can work at the large scales of real-world recycling facilities. Chemical recycling of plastics is a hot topic but has been difficult to make happen economically at the commercial scale.

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Putting an End to Plastic Separation Anxiety

Photo, posted November 28, 2016, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic In Lakes | Earth Wise

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We are always talking about the millions of tons of waste plastic that finds its way into the oceans and about the challenges of trying to remove it.  A new multinational study has found that the concentration of plastics and microplastics in some lakes is even worse than in the so-called garbage patches in the oceans and some of these lakes are even in remote places around the world

Scientists from institutes in multiple countries collected water samples from 38 lakes and reservoirs in 23 countries across six continents.  The samples were then all analyzed by the University of Milan to assess the presence of plastic particles more than a quarter millimeter in size.

The study found that two types of lakes are particularly vulnerable to plastic contamination:  lakes and reservoirs in densely populated and urbanized areas and large lakes with elevated deposition areas, long water-retention times, and high levels of human influence.

Lakes found to have the highest concentration of plastic included some of the main sources of drinking water for communities and were also important to local economies.  These included Lough Neagh in Northern Ireland, Lake Maggiore in Italy, and Lake Tahoe on the California/Nevada border.  Not all the lakes studied contained large amounts of plastic.  For example, Windermere, the largest lake in England, had very low concentrations of plastic in surface water.

This was the first global survey of the abundance and type of plastic pollution in lakes and reservoirs and the scale of freshwater plastic pollution is sobering indeed.  There is widespread concern that plastic debris is having harmful effects on aquatic species and ecosystem function and clearly is not limited to marine ecosystems.

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Plastic pollution is higher in some lakes than oceans

Photo, posted May 27, 2019, courtesy of Jonathan Cook-Fisher 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

Life In The Garbage Patch | Earth Wise

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A team of scientists has found thriving communities of coastal creatures living thousands of miles from their original homes and now ensconced on plastic debris in the Great Pacific Garbage Patch. 

A new study published in the journal Nature Ecology & Evolution reports that dozens of species of coastal invertebrate organisms – including tiny crabs and anemones – have been able to survive and reproduce on plastic garbage that has been floating in the ocean for years.

The Great Pacific Garbage Patch is an area in the ocean between California and Hawaii, larger than Texas, where plastic debris has been collected by the North Pacific Subtropical Gyre, one of five huge, spinning circular currents in the world’s oceans.  The patch is estimated to contain about 1.8 trillion pieces of plastic weighing an estimated 90,000 tons.  The Ocean Cleanup Initiative is dedicated to removing this immense accumulation of plastic, but it is an immense job.

Researchers discovered this new ecosystem after analyzing plastic samples collected by The Ocean Cleanup organization during its expeditions in the Pacific.  They were surprised to find 37 different invertebrate species that normally live in coastal water and only a dozen species that live in open waters.  These species have made their way from North America and have thrived.  So, the garbage patch has created a novel community that didn’t previously exist.

Debris from the Great Pacific Garbage patch constitutes the majority of debris arriving on Hawaiian beaches and reefs.  Hawaii’s fragile marine ecosystems have long been protected from invasive species because of the very long distances from North America or Asia.  With the coastal species now inhabiting the garbage patch, there is increased danger of colonization by them in Hawaii’s ecosystems.

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Coastal species persist on high seas on floating plastic debris

Photo, posted September 30, 2020, courtesy of Kees Torn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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