Earth Wise

A look at our changing environment.

You are here: Home / Archives for Waste

Waste

Sustainable Flip-Flops | Earth Wise

By Leave a Comment

Flip-flops are the world’s most popular shoe.  They are lightweight, comfortable, affordable, and durable.  In fact, the global market for flip-flops is expected to reach a whopping $23.8 billion by the year 2025. 

But the popularity comes with a price.  Flip-flops account for a troubling percentage of plastic waste that ends up in our landfills and oceans.  As a result, demand for alternatives is compelling researchers to develop more sustainable versions of the popular footwear.

Scientists at the University of California San Diego have spent years working on this issue, and recently announced a breakthrough.  According to a study recently published in Bioresource Technology Reports, the research team has formulated polyurethane foams – made from algae oil – to meet commercial specifications for mid-sole shoes and the foot-bed of flip-flops.   In other words, the scientists have created sustainable, biodegradable, and consumer-ready materials that could replace plastics in some footwear. 

The UC San Diego scientists collaborated with Algenesis Materials – a technology startup – on the research.  Together, they worked to not only create the shoes, but to degrade them as well.  The team tested their customized foams by immersing them in traditional compost and soil.  The algae-based materials degraded after just 16 weeks.  

The life of any material should be proportionate to the life of the product.  The researchers point out that it doesn’t make sense to create a product that will last 500 years if it’ll only be used for a year or two. 

The research team is currently working on production details with its manufacturing partners.  The creation of biodegradable flip-flops that meet commercial footwear standards could eliminate tons of plastic waste from the environment.   

************ 

Web Links

New science behind algae-based flip-flops

Flip Flops Market Size Worth $23.8 Billion by 2025

Photo, posted December 12, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Tough Plastics | Earth Wise

By Leave a Comment

Thermoset plastics are ones that contain polymers that cross-link together during the curing process to form an irreversible chemical bond.  This improves the material’s mechanical properties, provides chemical resistance, heat resistance, and structural integrity.  Thermosets include epoxies, polyurethanes, and rubber used for tires.  The big problem with thermosets is that they cannot be easily recycled or broken down after use.

Seventy-five percent of all plastics are thermoplastics, which can be recycled by heating them until they become liquid and can then be remolded.   Thermoset plastics, on the other hand, have such strong chemical bonds that they simply will not melt.  They will typically burn before they can be remolded.

Chemists at MIT have recently developed a way to modify thermoset plastics with a chemical linker that makes them much easier to break down, but still retain the mechanical properties that make them so useful.

In a study published in Nature, the researchers produced a degradable version of a thermoset plastic called pDCPD.  They then broke the plastic down into a powder and were able to use the powder to create more pDCPD.  The paper also proposed a theoretical model that suggests that their approach could be used for a wide range of other plastics and polymers, including rubber.

By adding a chemical called a silyl ether monomer to the liquid precursors that from pDCPD plastic, they found that the resultant material retained its mechanical strength but can be broken down into a soluble powder upon exposure to fluoride ions.

Using this approach with other thermoset materials, the researchers believe it will be possible to create recyclable versions of many of the toughest plastic materials.

**********

Web Links

Chemists make tough plastics recyclable

Photo, posted September 1, 2019, courtesy of Luke McKernan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Green Bills Pass In New York | Earth Wise

By 3 Comments

In late July, the two houses of the New York legislature passed a number of environmental bills covering a wide range of topics.

These included a bill to add protected status for streams that support fisheries and non-contact recreation.  A second bill bans the use of PFAS in food packaging.  A third bill classifies all wastes resulting from oil and gas exploration, development, extraction or production as hazardous waste, closing a previous loophole in the law.

A fourth bill requires water works corporations with more than 1,000 service connections to post their annual water supply statements online, thereby providing transparency and openness to water quality data.  A fifth bill expands protections for endangered species to protect them from environmental rollbacks by the federal government.

A sixth bill prohibits non-electric vehicles from parking in spaces designated for electric vehicle charging, thereby establishing penalties for this practice that is often done for spite.  A seventh bill bans the use of glyphosate – the herbicide found in Roundup and other products – on state property.

An eighth bill reduces the use of road salt in the Adirondacks.  A ninth bill requires supermarkets to make good faith efforts to donate edible excess food to qualifying entities such as food pantries, food banks, or similar entities.   A tenth bill bans certain uses of trichloroethylene or TCE, including as a vapor degreaser, an intermediate chemical to produce other chemicals, a refrigerant, or an extraction solvent.

When signed by the governor, these ten pieces of legislation will help protect New York’s environment, water, and health.  It was a busy session for green legislation.

**********

Web Links

Several Green Bills Pass in State Legislature

Photo, posted September 12, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plant-Based Bottles | Earth Wise

By Leave a Comment

Single-use plastic soda and water bottles are a real problem.  Every year, billions of them are produced – comprising nearly 300 million tons of plastic that mostly ends up in landfills or in the ocean.   This discarded plastic ends up on remote islands, in the snow atop mountains, and in trenches in the deepest parts of ocean.

There has been increasing pressure on beverage companies to put an end to this environmental disaster, but the convenience and economy of disposable bottles is just too attractive.

These bottles are made of plastic derived from oil and once they are produced, they take decades or even centuries to decompose.  Recycling them is a not-starter because it is cheaper to just make new ones.

A possible solution has emerged.  A Dutch company called Avantium has found a way to take plant sugars and transform them into a plastic capable of standing up to carbonated beverages like soda and beer but that will also break down in as little as a year in a composter or 3 years if left exposed to the elements.

Coca Cola and Carlsberg are working with Avantium to develop new drink packaging based on their material that could be in stores as soon as 2023.  The new packaging would be quite different from what we use today.  Instead of a clear or tinted bottle, beverages would come inside a cardboard container with a liner made of plant-based plastic.

It may take a while for people to get used to the change, but we have already managed to get used to milk, juice and other liquids coming in cardboard containers instead of glass or plastic bottles.  The benefits to the planet would make the effort well worthwhile.

**********

Web Links

Plant-Based Bottles Could Degrade In One Year

Photo courtesy of Avantium.

Earth Wise is a production of WAMC Northeast Public Radio.

Metal From Plants | Earth Wise

By 2 Comments

Large amounts of metal in soil are generally bad for plants.  But there are about 700 species of plants that thrive in metal-rich soils.  These plants don’t just tolerate minerals from soil in their bodies but actually seem to hoard them to ridiculous levels.

In areas where soils are naturally rich in nickel, typically in the tropics and Mediterranean basin, plants have either died off or have adapted to become nickel loving.  Slicing open a tree with this adaptation produces a neon blue-green sap that is actually one-quarter nickel, which is far more concentrated than the ore that typically feeds commercial nickel smelters.

A group of researchers from the University of Melbourne and other institutions is investigating whether this phenomenon is not just interesting but might also be of real commercial value.  They established a plot of land in a rural village in Borneo and have been harvesting growth from nickel-hyper accumulating plants.  Every six to twelve months, a farmer shaves off one foot of growth from these plants and either burns or squeezes the metal out.  After a short purification, they end up with about 500 pounds of nickel citrate, potentially worth thousands of dollars on international markets.

Phytomining – extracting minerals from hyper-accumulating plants – cannot fully replace traditional mining techniques.  But the technology could enable areas with toxic soils to be made productive and might allow mining companies to use plants to clean up their former mines and waste while actually collecting some revenue.

There are other plants that suck up cobalt, zinc, and similarly crucial metals.  With growing demand for metals, perhaps it is time to harvest them on the farm.

**********

Web Links

Down on the Farm That Harvests Metal From Plants

Photo courtesy of the University of Queensland.

Earth Wise is a production of WAMC Northeast Public Radio.

Food Waste And Access To Groceries | Earth Wise

By 1 Comment

One-third of all food produced is wasted, which turns out to be a major contributor to carbon emissions.  Most of the carbon emissions associated with food waste are related to the production of the food.  Reducing waste would trickle through the supply chain over time and ultimately less food would be produced.

A study at Cornell’s SC Johnson College of Business looked at a particular strategy for reducing food waste’s environmental impact:  opening more grocery stores.

It turns out that the more stores there are, the lower food waste will be.  Cornell Professor Elena Belavina created a model that incorporates data from the grocery industry, the U.S. Census Bureau, and other academic studies.

When applied to Chicago, which is typical of many American cities, the model predicts that by adding just three or four markets within four-square-mile area, food waste would be reduced by 6 to 9 percent.  This would achieve an emissions reduction comparable to converting more than 20,000 cars from fossil fuels to electric power.  According to the model, not only would food waste be reduced, but so would grocery bills.  By trimming food waste and travel costs, consumers would spend up to 4% less.

Most big cities are well below their ideal density of grocery stores that would minimize food waste. When consumers can purchase perishable goods nearby, they shop more often but buy less each time.  There is less food sitting at home, so there is a much lower likelihood that food will spoil.

New York City, which has an abundance of produce stands and neighborhood markets, comes close to having the ideal density of markets.  Basically, the way to reduce food waste is to bring less groceries home.

**********

Web Links

Better access to groceries could reduce food waste, emissions

Photo, posted March 22, 2009, courtesy of Nick Saltmarsh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Safer Disposal Of Printed Circuit Boards | Earth Wise

By Leave a Comment

Printed circuit boards are key elements of modern electronic devices that support and connect all of their electronic components.  On average, they are composed of 30% metallic and 70% nonmetallic substances.

Once the circuit boards have served their purpose, they are often burned or buried in landfills, and can pollute the air, soil, and water.  The biggest problem is that they have brominated flame retardants added to them in order to keep them from catching fire.  Compounds in brominated flame retardants have been linked to endocrine disorders and fetal tissue damage.

Many circuit boards are recycled to recover valuable materials – generally the metals they contain.  But recycling has its own problems.  Metallic components can be recovered from crushed circuit boards by magnetic and high-voltage electrostatic separations.  When the metals are removed, what remains are resins, reinforcing materials, brominated flame retardants, and other additives, which are of little value and present various dangers.

Researchers at Sun Yat-sen University in China have developed a ball-milling method to break down these potentially harmful compounds, enabling safe disposal.  A ball mill is a rotating machine that uses small agate balls to grind up materials. The researchers also added iron powder, which helps remove bromine from organic compounds by breaking the carbon-bromine bonds in the flame retardants.  The result was particles with half of their bromine content removed as well as decomposition of phenolic resin compounds.

The ever-increasing proliferation of device technology had led to a new set of pollution and waste challenges facing society.  Research on ways to reduce the impact of high-tech garbage is an important need for society.

**********

Web Links

Toward safer disposal of printed circuit boards

Photo, posted February 18, 2018, courtesy of Diego Torres Silvestre via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

American Households and Food Waste | Earth Wise

By Leave a Comment

Food waste is a big problem.  According to the United Nations, approximately one-third of the food produced globally – more than 1.4 billion tons – goes to waste.  If food waste was a country adding carbon to the atmosphere, it would be the world’s third largest emitter of greenhouse gases – behind only the U.S. and China.  All of this food waste takes place in a world where 815 million people – more than 10% of the people on the planet – are chronically undernourished.

A new study recently published in the American Journal of Agricultural Economics has analyzed the level of food waste for individual American households. It found that American households waste, on average, nearly one-third of all the food they acquire.  This wasted food has an estimated aggregate value of $240 billion annually.  Divided by the number of U.S. households, this food waste could be costing the average household about $1,866 per year. 

According to researchers, the households with higher household incomes generate more food waste.  Those with healthier diets, which include more perishable fruits and vegetables, also waste more food.  

Meanwhile, households with greater food insecurity, especially those that participate in the federal SNAP food assistance program, as well as those households with a larger number of members, were associated with less food waste.  Households that use shopping lists and those that travel further to reach the grocery store were also associated with lower levels of food waste. 

When food is wasted, the resources used to produce food, including land, energy, water and labor, are wasted as well.  We have to do better. 

**********

Web Links

SAVE FOOD: Global Initiative on Food Loss and Waste Reduction

US households waste nearly a third of the food they acquire

Photo, posted March 22, 2009, courtesy of Nick Saltmarsh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Livestock And Sustainable Food Systems | Earth Wise

By Leave a Comment

Animal-based agriculture has endured a great deal of criticism with regard to its contributions to climate change and its other environmental impacts.  But its contributions to a sustainable food system are by no means all bad.  In fact, livestock play important roles in sustainable, regenerative agro-food systems.

Animals’ natural biological processes enable them to consume plant and food residues that are either indigestible by humans, unpalatable to people, or are no longer sellable for various reasons, all referred to as IUUB biomass.  There are many examples.

One dairy farm receives daily deliveries of apple waste from a processing facility that supplies apple slices for school lunches.  Another local dairy gets three truckloads of vegetable and fruit discards, along with expired bread products, each week.  No longer useful for consumers, these foodstuffs become feed for cattle rather than going to a landfill.  Even the booming market for plant-based foods like artificial meat for consumers has generated a surge of processing byproducts that can be consumed by livestock.

On a national scale, livestock are consuming millions of pounds of otherwise unusable IUUB created in the production of products like soybean and canola oils, orange juice, ethanol, and more.

While the livestock industry needs to keep working to minimize its environmental impact and there are many reasons to eat less meat, livestock farming is an integral part of our agro-food systems.  Farmers are embracing techniques to produce meat, milk and eggs as efficiently and sustainably as possible, minimizing agriculture’s climate-contributing footprint in the process.

**********

Web Links

Amazing Cows Hold Promise in Pioneering Sustainable Food Systems

Photo, posted May 11, 2019, courtesy of Theo Stikkelman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conspicuous Consumption

By 2 Comments

Human civilization consumes vast amounts of material.   The Circle Economy think tank actually puts some numbers on it.  According to their latest report, the amount of material consumed by humanity has passed 100 billion tons every year.  So, on average, every person on Earth uses more than 13 tons of materials per year.

That number has quadrupled since 1970, which is far faster than the population, which has only doubled during that time.  In the past two years alone, consumption has jumped by more than 8%.  While this has been going on, the proportion being recycled has been falling.

Of the 100 billion tons of materials, half of the total is sand, clay, gravel, and cement used for building, along with other minerals used for fertilizer.  Coal, oil and gas make up 15% and metal ores 10%. The final quarter are plants and trees used for food and fuel.  About 40% of all materials are turned into housing.  A third of the annual materials consumed remain in use, such as in buildings or vehicles.  But 15% is emitted into the atmosphere as greenhouse gases and a third is treated as waste.

The global emergencies of climate change and disappearing wildlife have been driven by the unsustainable extraction of fossil fuels, metals, building materials, and trees.  The authors of the report warn that if we continue to treat the world’s resources as limitless, we are heading for a global disaster.

The Circle Economy think tank promotes the idea of a circular economy in which renewable energy supports systems where waste and pollution are reduced to zero.  Some nations are taking steps towards circular economies, while others are not.  This is a problem we can’t allow to be unaddressed.

**********

Web Links

World Consumes 100 Billion Tons of Materials Every Year, Report Finds

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

XXXXXXXXXXX

Excluding Climate Change From Infrastructure Planning | Earth Wise

By Leave a Comment

According to a new Trump administration proposal, federal agencies would no longer need to take climate change into account when evaluating infrastructure projects.  The proposed changes to the 50-year-old National Environmental Policy Act (NEPA) are aimed at speeding up approvals for highway construction, pipelines, oil and gas leases, and other major infrastructure projects.   

Under NEPA, federal agencies are required to consider how their proposed actions would affect everything from water quality to wildlife to greenhouse gas emissions.  They’re also required to understand how rising seas and other consequences of climate change might affect a given project.  These requirements have proven to be an obstacle to projects like the Keystone XL pipeline, for example. 

According to reporting in the New York Times, the administration also plans to narrow the range of projects that require environmental review in the first place.  That could make it more likely for projects to be approved without having to disclose plans to do things like cut down trees, discharge waste, or increase air pollution. 

The administration says that the changes would improve the environmental review and permitting process while ensuring a safe, healthy, and productive environment. Environmentalists say the proposed changes would weaken critical safeguards for air, water, and wildlife. 

The proposed changes to NEPA would revise the rules that guide the implementation of the law, as opposed to amending the act itself.  Once these proposed changes appear in the federal register, the public will have 60 days to comment on them. 

A decision on whether or not to weaken the nation’s benchmark environmental law is expected before November.

**********

Web Links

Trump Rule Would Exclude Climate Change in Infrastructure Planning

Photo, posted February 23, 2016, courtesy of Lissy Wild via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic-Eating Mushrooms

By 2 Comments

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.

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.

**********

Web Links

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.

A Green Way To Turn Blue

By Leave a Comment

Indigo dye is what is used to color denim cloth and blue jeans.  Historically, the dye came from a tropical plant most often found on the Indian subcontinent.  Eventually, it became economically favorable to synthesize the dye instead and almost all of the 50,000 tons of the dye used annually is synthetic.

The processes used to make synthetic indigo are efficient and inexpensive, but they often require toxic chemicals and create a lot of dangerous waste.  Researchers at the Department of Energy’s Joint BioEnergy Institute have now developed an eco-friendly production platform for a blue pigment called indigoidine.  It has a similarly vividly saturated blue hue as synthetic indigo.

The researchers were investigating the ability of various fungal strains to express large enzymes known as NRPSs.  They chose an NRPS that converts two amino acid molecules into indigoidine – a blue pigment – in order to make it easy to tell if the strain engineering had worked.  Having the culture turn blue was an effective indicator.

Their primary interest was not the pigment but when they saw just how blue the culture was for one particular fungus, they realized that the fungal strain did not just produce indigoidine; it produced large amounts of it.

Thus they have found a way to efficiently produce a blue pigment that uses inexpensive, sustainable carbon sources instead of harsh chemicals.  There is already a great deal of interest from the textile industry, where many companies are eager for more sustainably sourced pigments because customers are increasingly aware of the impacts of conventional dyes.

Thanks to a talented fungus called Rhodosporidium toruloides, there may now be a green way to turn blue.

**********

Web Links

Blue Pigment from Engineered Fungi Could Help Turn the Textile Industry Green

Photo, posted March 7, 2006, courtesy of Willi Heidelbach via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Powering Cars With Cactus Juice

By Leave a Comment

Back in 2016, a company called Nopalimex, located in Micoacan, central Mexico, built the world’s first cactus-powered energy plant.  The facility utilizes a biodigester to make biogas from nopal, also known as prickly pear cactus.  The nopal plant has been called the ‘Green Gold of Mexico’ and is a staple in Mexican diets, medicine and cosmetics.

Nopalimex is now using the cactus to make biofuel for vehicles.

The fruit of the cactus is pureed, mixed with manure, and then left to decompose, producing methane.  The methane produced – about eight tons a day – fuels the biodigester which powers the company’s corn chip and cactus chip production and is being tested in a fleet of government vehicles.

The biogas will cost just 65 cents per liter, which is about a third cheaper than the cost of regular gasoline.  Using prickly pear as a feedstock for biofuel is attractive because it can be grown in places where traditional energy crops cannot.  One can imagine vast fields of cacti in remote, arid areas of the country where normal crops cannot grow.  It would not suck up the resources or space needed to feed people, which is an ongoing criticism of current bioenergy crops.

As long as the nopals are regularly replanted, the process is almost entirely sustainable, producing only water and nopal waste, which can be used to fertilize other crops.

Finding sustainable ways to produce fuel while doing minimal damage to the environment is an important challenge for countries around the world.  In Mexico, harnessing the power of the prickly pear cactus is a unique and clever solution.

**********

Web Links

Mexico’s ‘green gold’: The company powering cars with cactus juice

Photo, posted July 8, 2006, courtesy of Christian Frausto Bernal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Sensor For Spoiled Milk

By Leave a Comment

A new sensor technology developed at Washington State University may eventually make expiration dates on milk a thing of the past.  The sensor essentially can ‘smell’ whether milk is still good or has gone bad.

The sensor consists of chemically coated nanoparticles that react to the gas produced when bacterial growth on milk has taken place.  When such bacteria grow, they produce a volatile compound that doesn’t smell good.  So, when we open a carton of milk that has begun to spoil, our noses tell us so immediately.

The new sensor does not have to be in contact with the milk.  It detects the volatile gases produced by the bacteria and it changes color. So far, it has only been demonstrated in a controlled lab environment.

To really be useful, the sensor would ideally be able to show how long the milk has before it spoils.  Currently, it only shows whether it is ok or already spoiled. The researchers are working on the enhanced version of the sensor.

The researchers envision working with the dairy industry to integrate the sensor technology into a milk bottle’s plastic cap so that consumers can easily see how much longer the milk will stay fresh.  Current expiration dates on milk are based on best-case scenarios. They are only accurate if the milk has been stored at the correct temperature the entire time.  Unfortunately, milk can inadvertently spend time above refrigerator temperature during shipment or transportation home from the store.  If the new sensor technology can be successfully developed, it will be possible to know for sure whether that bottle of milk is good.

**********

Web Links

Sensor can detect spoiled milk before opening

Photo, posted March 8, 2011, courtesy of Roxanne Ready via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Meal Kits And The Environment

By Leave a Comment

Meal kit services have become extremely popular in recent years.  These are companies that deliver a box of pre-portioned ingredients and a chef-created recipe to your door to make home-cooked meals easy and practical for busy people.  Leading companies like Blue Apron, HelloFresh, and Plated have been joined by dozens of others competing in the meal kit market.  As of last year, annual sales for these things were over $3 billion and growing at more than a 20% annual rate.

A major rap against meal kits has been their environmental impact, mostly centered around the amount of packaging waste they generate.  While there is most certainly lots of packaging waste associated with meal kits, it turns out that their overall carbon footprint is actually rather good compared with conventional ways to make homecooked meals.

A study from the University of Michigan looked at the cradle-to-grave impact of meal kits, taking into account every major step in the lifetime of the food ingredients and the packaging – agricultural production, packaging production, distribution, supply chain losses, consumption, and waste generation.

Surprisingly, meal kits have a much lower overall carbon footprint than the same meals made from ingredients purchased at the grocery store – even including their packaging.  The main reason is that pre-portioned ingredients and a streamlined supply chain lower overall food losses and waste for meal kits compared to store-bought meals.  Pre-portioning simply results in fewer ingredients that end up being wasted.  Meal kits also have radically different supply chain structures than foods sold in supermarkets.

Whether the economics and culinary aspects of meals kits are advantageous for many people is an open question, but apparently from an environmental perspective, they are just fine.

**********

Web Links

Climate change has worsened global economic inequality

Photo, posted June 11, 2018, courtesy of Marco Verch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Roads From Ocean Plastic

By Leave a Comment

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.

**********

Web Links

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.

Antibiotics In The Environment

By Leave a Comment

Antibiotics make their way into the environment in many ways.  Sources of antibiotic pollution include the waste from large-scale animal farms and the wastewater from hospitals, municipalities, and antibiotic manufacturing.

A new study has discovered concentrations of antibiotics in some of the world’s rivers exceed safe levels by up to 300 times.  In the project, researchers looked for 14 commonly used antibiotics in rivers in 72 countries across six continents.  They found antibiotics at 65% of all the sites they examined. 

The antibiotic ciproflaxacin was the compound that most frequently exceeded safe levels, surpassing that threshold in 51 places. The antibiotic metronidazole exceeded safe levels by the biggest margin.  Concentrations of this antibiotic at one site in Bangladesh was 300 times greater than the safe level.  The most prevalent antibiotic was trimethoprim.  It was detected at 307 of the 711 sites. 

Some of the world’s most iconic rivers were sampled as a part of this study, including the Danube, Mekong, Seine, Thames, Tiber and Tigris. 

The project, which was led by the University of York, found that high-risk sites were often located near wastewater treatment systems, waste or sewage dumps, and in some areas of political unrest. 

Safe levels for antibiotics, which were recently established by the AMR Industry Alliance, range from 20,000 to 32,000 nanograms per liter depending on the compound. 

According to the research team, solutions to the problem of antibiotic contamination should include infrastructure investment, tighter regulation, and the remediation of already contaminated sites. 

**********

Web Links

Antibiotics found in some of the world’s rivers exceed ‘safe’ levels, global study finds

Photo, posted October 7, 2013, courtesy of Nicola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Supermarkets And Zero-Waste

By Leave a Comment

There are about 38,000 supermarkets in the United States alone and they are responsible for vast quantities of waste in the form of single-use plastic bags, plastic containers that store food products, and food waste as well.  Globally, over 80% of poll respondents feel strongly that companies should help improve the environment.  Responding to this message, markets are starting to make changes.

In a number of places, there are now markets that are package-free.  The Nada grocery store in Vancouver and Precycle in Brooklyn are examples of zero waste grocery stores.  Websites like Litterless provide online help for customers trying to find packaging-free grocery stores.

Markets are not only changing their packaging, they are using artificial intelligence to develop more sustainable production processes and seeking other ways to reduce waste.

On average, Americans throw away over 300 plastic bags a year, but an increasing number of grocery retailers are making commitments to more sustainable, plastic-free options.  It isn’t just small stores either.  Grocery giant Kroger plans to eliminate plastic bags in its stores by 2025.  When that happens, it means that 6 billion plastic bags will no longer be distributed.  Big Y stores will fully transition to reusable bags by next year.  More and more cities and states are banning or imposing fees on plastic bags. 

An interesting statistic shows that the age group of Americans that is leading the adoption of reusable grocery bags is not millennials but in fact is people over 50.  With multiple generations now indicating that they want shopping to be more sustainable, it is likely that supermarkets will strive to help make that happen.

**********

Web Links

Why More Supermarkets Are Committing to Zero-Waste

Photo, posted March 4, 2013, courtesy of Dean Hochman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

By Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology.  Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals.  As a result, economically exploitable ore deposits are uncommon.  There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones.  As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock.  The U.S. alone mined 28 million tons of phosphate rock in 2017.  (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone.   World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste.  This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

**********

Web Links

Critical Materials: Researchers Eye Huge Supply of Rare-Earth Elements from Mining Waste

Photo, posted June 19, 2015, courtesy of David Stanley via Flickr.

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...)