Earth Wise

A look at our changing environment.

You are here: Home / Archives for pollutants

pollutants

Lampshades And Indoor Air Pollution | Earth Wise

By Leave a Comment

We mostly think of air pollution as an outdoor problem.  Common sources of air pollution include emissions from vehicles, byproducts of manufacturing and power generation, and smoke from wildfires.  What we don’t often spend a lot of time thinking about is indoor air quality. 

Indoor air pollution refers to harmful pollutants within buildings and structures, which can lead to a myriad of health issues.  Sources of indoor air pollution include smoke from tobacco products, as well as volatile organic compounds (VOCs), including acetaldehyde and formaldehyde, emitted from things such as paints, cleaning products, plastics, and cooking. 

A team of scientists from South Korea’s Yonsei University has developed a special coating that when applied to lampshades can convert pollutants into harmless compounds.  Composed of titanium dioxide and a small amount of platinum, this thermocatalyst can be applied to the inside surface of a lampshade and is triggered to break down VOCs when warmed by the lamp’s existing incandescent or halogen bulb.

In lab tests, the coating was applied to the inside of an aluminum lampshade, warmed by a halogen bulb, and then placed into a sealed chamber containing air and acetaldehyde gas.  The researchers found that the material quickly converted the gas into acetic acid, then into formic acid, and finally into carbon dioxide and water. The scientists are now looking for ways to extend the pollutant-destroying-lampshade concept to LED lightbulbs. 

The findings offer a promising and eco-friendly solution to improve indoor air quality and reduce the health risks associated with prolonged exposure to VOCs. 

**********

Web Links

Clever coating turns lampshades into indoor air purifiers

Photo, posted March 21, 2009, courtesy of Levent Ali via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy From Fruit Waste | Earth Wise

By Leave a Comment

In the Back to the Future films, Doc Brown ran his DeLorean time machine on food scraps.  It was a fun bit of science fiction.  But researchers at the University of British Columbia Okanagan in Canada are investigating the potential for using food waste to generate power.

Food waste is not a candidate to replace solar or wind power, but it could be a source of energy for powering fuel cells.  As it is, food waste represents a sustainability challenge because of its detrimental impacts on the economy and the environment.  Organic waste represents a significant fraction of the material in landfills and contributes to methane production, air pollution, and other harmful pollutants.

The UBC researchers focused on fruit waste, which is abundantly available in agricultural regions.  They have devised microbial fuel cells that convert fruit waste into electrical energy using an anaerobic anode compartment.  That is a chamber in which anaerobic microbes – ones that don’t need oxygen – utilize the organic matter to convert it into energy.  The microbes consume the fruit waste and produce water while generating bioelectricity.

It is not like the Back to the Future time machine where you can just toss in scraps of whatever is on hand.  Different types of fruits provide different results when used in the microbial fuel cell. The process works best when the food waste is separated and ground into small particles.  There is a long way to go before the technology could produce bioenergy on a commercial scale, but there is considerable potential for doing something useful with something that is currently worthless.

**********

Web Links

UBCO researchers aim to energize fruit waste

Photo, posted July 24, 2011, courtesy of Andrew Girdwood via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air Pollution In The Arctic | Earth Wise                     

By Leave a Comment

Climate change is shrinking the Arctic ice cover, which is making it easier for ships to travel along the northern coast of Russia, known as the Northern Sea Route or the Northeast Passage.  There is also the Northwest Passage, which connects the Atlantic and Pacific Oceans via waterways through the Canadian Arctic Archipelago.

More than 600 fishing vessels sail the waters of the Arctic Ocean, but these fishing vessels are not the worst offenders when it comes to the growing problem of air pollution.  Giant natural gas tankers are becoming a much bigger problem.

In 2021, only 26 natural gas tankers traveled through Arctic waters.  But these ships can be 1000 feet long or more and produce far more CO2 emissions than fishing boats.   In 2019, the tankers accounted for 28% of the emissions and the number of them cruising the Arctic has been growing.

As the ice cover in the Arctic continues to shrink, more and more ships of all varieties, including cruise ships, fishing vessels, as well as tankers, are coming north and spending more time in the Arctic.  Any increases in ship traffic will increase the pollutant load in the Arctic and the Arctic is one of the most vulnerable environments in the world.

Between 2013 and 2019, the aggregated nautical miles that vessels traveled in what is called the Polar Code area increased by 75%. It isn’t just that more ships like tankers are going there.  It is that their operational season is expanding.

Air pollution isn’t the only problem.  Shipping in the Arctic brings with it light pollution, noise, marine litter, and more.  Only zero activity has zero pollution.

**********

Web Links

The worst polluters in the Arctic are not what you think

Photo, posted February 26, 2015, courtesy of Chris Parker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electric Cars And Cleaner Air | Earth Wise

By Leave a Comment

Cities are awash in microscopic soot and other pollutants from the tailpipes of vehicles.  Apart from contributing substantially to the warming of the planet, these emissions have a significant impact on human health.  Research at Cornell University has determined that the continued growth of electric cars will lead to cleaner air and reduced human mortality in most if not all U.S. metropolitan areas.

The study, published in Renewable and Sustainable Energy Reviews, estimated the health impact and consequential economic impact of cleaner air in American cities as a result of the transition to electric vehicles.

For example, by 2050, Los Angeles will have 1,163 fewer premature deaths annually, corresponding to $12.6 billion in economic health benefits.  Greater New York City could see 574 fewer deaths a year leading to $6.24 billion in associated economic gains.

Global sales of electric cars have grown steadily.  In 2016, they accounted for less than 1% of the market.  That share grew to 2.2% in 2018, 4.1% in 2020, and 6.6% in 2021.

In the U.S., electric cars accounted for 4.5% of sales in 2021, but in many cities, the numbers were much higher. 

These trends are likely to accelerate as a combination of government policies and major decisions by automakers drive a rapid transition to electrification.  While mitigating the effects of climate change continues to be the main driving force for that transition, the human health benefits will be a very significant reward for doing the right thing for the planet.

**********

Web Links

Electric car sales drive toward cleaner air, less mortality

Photo, posted May 11, 2021, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cleaning Up Forever Chemicals | Earth Wise

By Leave a Comment

PFAS, per- and polyfluoroalkyl substances, are chemical pollutants that threaten human health and ecosystem sustainability.  They are used in a wide range of applications including food wrappers and packaging, dental floss, firefighting foam, nonstick cookware, textiles, and electronics.  Over decades, these manufactured chemicals have leached into our soil, air, and water.  Chemical bonds in PFAS molecules are some of the strongest known, so the substances do not degrade easily in the environment.

Studies have shown that at certain levels, PFAS chemicals can be harmful to humans and wildlife and have been associated with a wide variety of health problems.

Currently, the primary way to dispose of PFAS chemicals is to burn them, which is an expensive multistep process.  Even trace levels are toxic, so when they occur in water in low amounts, they need to be concentrated in order to be destroyed.

Researchers at Texas A&M University have developed a novel bioremediation technology for cleaning up PFAS.  It uses a plant-derived material to absorb the PFAS which is then eliminated by microbial fungi that literally eat the forever chemicals.

The sustainable plant material serves as a framework to adsorb the PFAS.  That material containing the adsorbed PFAS serves as food for the fungus.  Once the fungus has eaten it, the PFAS is gone. 

The EPA has established a nationwide program to monitor the occurrence and levels of PFAS in public water systems and is considering adding PFAS threshold levels to drinking water standards.  If this happens, the technology developed at Texas A&M may become an essential part of municipal water systems.

**********

Web Links

Texas A&M AgriLife develops new bioremediation material to clean up ‘forever chemicals’

Photo, posted August 10, 2013, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Removing Lead From Water With Beer Yeast | Earth Wise

By Leave a Comment

Lead and other heavy metals in water are a serious global problem that is worsening because of electronic waste and discharges from mining operations.  In the U.S., over 12,000 miles of waterways are impacted by mine-drainage water that is rich in heavy metals.

Lead in particular is highly toxic, especially to children.  The European Union established a standard for allowable lead in drinking water of only 5 parts per billion.  In the US, the EPA has declared that no level of lead at all is safe.

Researchers at MIT have recently discovered that inactive yeast can be effective as an inexpensive, abundant, and simple material for removing lead contamination from drinking water supplies.  The MIT study shows that the method works even at parts-per-billion levels of contamination.

The method is called biosorption, in which inactive biological material is used to remove heavy metals from water.  Previously, it has been studied at parts-per-million contaminant levels, but the MIT study shows that it works at much lower levels as well.

The team studied a type of yeast widely used in brewing.   The yeast cells used are inactive and desiccated and require no special care.  Such yeast is abundantly available as a waste product from beer brewing and various other fermentation-based industrial processes. 

The researchers estimate that to clean a water supply for a city the size of Boston would require about 20 tons of yeast a day, or 7,000 tons a year.  That seems like a lot, but one single brewery, the Boston Beer Company, generates 20,000 tons a year of surplus yeast that is no longer useful for fermentation.

**********

Web Links

Could used beer yeast be the solution to heavy metal contamination in water?

Photo, posted September 5, 2017, courtesy of Allagash Brewing via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Florida’s Starving Manatees | Earth Wise

By Leave a Comment

Manatees, also called “sea cows”, have been the victims of farm runoff.  They have starved to death by the hundreds along Florida’s east coast because algae blooms fed by nitrogen-rich fertilizer runoff are proliferating on the ocean surface and blocking sunlight from reaching seagrass below.  Seagrass is the primary source of food for manatees in the winter.  As seagrass dies off, so do the manatees.

Over 1,000 manatees have been found dead so far this year.  It is estimated that fewer than 8,000 remain in Florida waters.  Efforts are underway to restore coastal seagrass in the region as well as clams and oysters, which filter pollutants from water.  Unless the water is cleared up, it will be difficult to regrow the seagrass.  But the current situation is that manatees are so short on food that they are eating seagrass roots, killing the plants and thwarting efforts to help seagrass recovery.

Given this dire situation, the federal governmental has approved a program of feeding manatees.  The starving animals will be fed by hand in Florida, which is a rare wildlife intervention.  Conservation agencies tend to favor leaving wild animals to their own foraging and hunting so that they don’t become dependent on human handouts.

During the trial phase of the program, wildlife experts are likely to feed the animals romaine lettuce and cabbage, which is what manatees in captivity eat.  The hope is to give the animals enough additional food for them to get through the winter.  The trial feeding will begin on private property.  It remains illegal for the public to feed manatees.

**********

Web Links

Florida to feed starving manatees in rare conservation move

Photo, posted February 21, 2008, courtesy of Keith Ramos/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disappearing Mountaintop Glacier Ice | Earth Wise

By Leave a Comment

A newly released study has found that mountaintop glacier ice in the tropics of all four hemispheres has diminished dramatically over the past 50 years.  Among the findings of the study, published in the journal Global and Planetary Change, are that a glacier near Puncak Jaya, in Papua New Guinea, lost about 93% of its ice between 1980 and 2018.  Between 1986 and 2019, the area covered by glaciers on top of Mt. Kilimanjaro in Africa decreased by nearly 75%.

The study combined NASA satellite imagery with data from ice cores drilled during field expeditions on tropical glaciers around the world.  The combination of measurements demonstrated that climate change is causing these glaciers to disappear and that the ice loss has accelerated in recent years.

The study looked at glacier ice in Kilimanjaro in Tanzania, the Andes in Peru and Bolivia, the Tibetan Plateau and the Himalayas, and ice fields in Papua, New Guinea.  Collecting ice cores from these places provides information on the climate in these regions over the centuries and millennia.  As snow falls on a glacier each year, it is buried and compressed to form layers that preserve the chemistry of snow, pollutants from the atmosphere, and biological material such as plants and pollen.

Glaciers in the tropics respond more quickly to climate change because they exist in the warmest areas of the world and survive only at very high altitudes. For many of these tropical glaciers, it is too late to prevent their demise.  It is not too late to attempt the slow down the buildup of greenhouse gases in the atmosphere that is causing the planet to warm, but we don’t have unlimited time to act.

**********

Web Links

Mountaintop glacier ice disappearing in tropics around the world

Photo, posted February 12, 2009, courtesy of Christoph Strassler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaner Water Using Corn | Earth Wise

By Leave a Comment

Corn is the largest agricultural crop in the U.S., and it is also one of the most wasteful.  About half of the harvest ends up as stover – corn stalks, leaves, husks, and cobs – once the kernels are used for food.

Corn stover has relatively few commercial or industrial uses.  It can be used to produce biofuel, but that is not very energy efficient.  It is sometimes used as a low-quality livestock feed as well.  Mostly, it is just burned if it is used at all.

Researchers at the University of California Riverside have developed an energy-efficient way to make good use of stover by transforming it into activated carbon for use in water treatment.

Activated carbon – often called activated charcoal – is an organic material that is specially treated to contain millions of microscopic pores that make it highly absorbent.  It has many industrial uses, the most common of which is for filtering pollutants out of drinking water.  Most household water filters such as Brita filters as well as the ones built into refrigerators make use of activated carbon.

The Riverside researchers explored methods for producing activated carbon from charred corn stover and found that processing the material with hot compressed water – a process known as hydrothermal carbonization – produced highly absorbent activated carbon with superior properties compared to material produced by slow pyrolysis, where corn stover is charred at increasing temperatures over a long period of time.

According to the researchers, it is important to create approaches that convert waste into high-value materials, fuels, and chemicals in order to create new value streams and eliminate the environmental harm that comes from a so-called “take-make-dispose” economic model.

**********

Web Links

Cleaner Water Through Corn

Photo, posted September 15, 2010, courtesy of the United Soybean Board / the Soybean Checkoff via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Deep Learning And Dirty Air | Earth Wise

By Leave a Comment

Poor air quality is a major global problem.  According to the World Health Organization, exposure to air pollution is linked to the premature deaths of an estimated seven million people every year.  In fact, 9 out of 10 people breathe air that contains more pollutants than what the WHO considers safe.  Air pollution is the fourth largest threat to human health, trailing only high blood pressure, dietary risks, and smoking.

But predicting pollution levels at a given place and time remains challenging.  According to a new study recently published in the journal Science of the Total Environment, scientists are turning to deep learning to improve air quality estimates. 

According to researchers, satellite observations and ground observations both measure air pollution, but both have major limitations.  For example, satellites may collect data at the same time and at the same location each day, but they miss how emissions may vary throughout the day.  Ground-based observations from weather stations do continuously collect data, but they only do so in a limited number of locations.    

As a result, scientists have turned to deep learning – a type of machine learning – to analyze the relationship between satellite and ground-based observations of nitrogen dioxide around Los Angeles.  Nitrogen dioxide is associated with emissions from traffic and power plants.  The researchers were able to rely on the learned relationship to take daily satellite observations and create hourly estimates of atmospheric nitrogen dioxide levels in approximately three mile grids.     

According to the research team, this study could be repeated for other greenhouse gases, and applied to different cities and regions – or even whole continents. 

**********

Web Links

Scientists turn to deep learning to improve air quality forecasts

Air Pollution

Photo, posted November 4, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Short-Lived Climate Forcing Pollutants | Earth Wise

By Leave a Comment

When talking about the causes of climate warming, it is common practice to bundle together various pollutants and express their effects in terms of “CO2 equivalence.”  This involves comparing climate effects of the pollutants on a 100-year timescale.  Recent research from the Institute for Advanced Sustainability Studies in Germany points out the problems with this approach.

One of the worst qualities of carbon dioxide is that it accumulates in the atmosphere.  Once it gets there, it stays there for anywhere from decades to millennia.  On the other hand, short-lived climate forcing pollutants – or SLCPs – stay in the atmosphere for significantly shorter periods.  However, some of these are far more effective at trapping heat in the atmosphere.  As a result, the atmosphere and climate system react much more quickly to reductions in the emission of these pollutants.

The IASS research study determined that reducing SLCP emissions is an important way to slow near-term climate warming as well as having other positive benefits such as reducing air pollution and improving crop yields.  A number of studies indicate that a rapid reduction in SLCP emissions could slow the rate of climate change and reduce the risk of triggering dangerous and potentially irreversible climate tipping points.

Examples of SLCPs are the methane gas emitted from landfills and hydrofluorocarbons that are still widely used as coolants. HFCs only persist in the atmosphere for 15 years but are nearly 4,000 times more effective in trapping heat over a 20-year period.

In order to mitigate the most harmful consequences of climate change, we need to minimize both the near-term climate impacts of SLCPs and the long-term climate impacts of carbon dioxide.

**********

Web Links

More Than Just CO2: It’s Time To Tackle Short-Lived Climate-Forcing Pollutants

Photo, posted March 10, 2020, courtesy of Jonathan Cutrer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Finding Methane Leaks from Space | Earth Wise

By Leave a Comment

There is growing concern about the climate effects of methane leaking from oil and gas wells.  The 20-year global warming potential of methane is 84, meaning that over a 20-year period, it traps 84 times more heat per mass unit than carbon dioxide.  Global methane concentrations have increased by nearly a factor of 3 since the industrial revolution.

More than a century of oil and gas drilling has left behind millions of abandoned wells, many of which are leaching pollutants into the air and water.   In the U.S. alone, more than 3.2 million abandoned oil and gas wells emitted 280,000 tons of methane just in 2018.  And the data is incomplete.

Part of the problem is finding out which wells are leaking.  Ground-based sensors or airplanes and drones are effective ways to find leaks but considering how many wells there are to check, the costs are considerable, and the process is time consuming and complicated. 

New technology is coming along that uses satellites to detect methane leaks.  A Canadian company called GHGSat recently used satellites to detect what it has called the smallest methane leak ever seen from space and has begun selling data to emitters interested in pinpointing leaks.

Another company, New York-based Bluefield Technologies, plans a group of satellites for launch in 2023 that promises even finer resolution.  The Environmental Defense Fund, with support from Jeff Bezos’ Earth Fund, plans to launch MethaneSAT in the next couple of years, which is designed to find small sources of methane.

Research at Stanford University determined that just 5% of methane leaks produce around half the total leakage. 

**********

Web Links

New Technology Claims to Pinpoint Even Small Methane Leaks From Space

Photo, posted June 8, 2011, courtesy of Jeremy Buckingham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Menace Of Abandoned Oil Wells | Earth Wise

By Leave a Comment

More than a century of oil and gas drilling has left behind millions of abandoned wells and many of them are leaching pollutants into the air and water.  Drilling companies continue to abandon even more wells as demand for oil diminishes and bankruptcies become more common.

Leaks from abandoned wells have long been known to be an environmental problem and a health hazard.  They have been linked to many instances of groundwater contamination and to dangerous fumes near homes and farms.

There have recently been efforts to track the amounts of methane leaching from abandoned oil and gas wells, and the figures in United States are alarming.  According to the most recent EPA report, more than 3.2 million abandoned oil and gas wells emitted a total of 281,000 tons of methane in 2018.  That is the climate-damage equivalent of consuming about 16 million barrels of crude oil, which is as much as the U.S. uses in a typical day.  According to the EPA, the actual amount could be as much as three times higher, because of incomplete data.   The agency believes that most of the methane comes from more than 2 million abandoned wells that were never properly plugged.

New York’s Department of Environmental Conservation has records of over 2,000 abandoned wells, but the state believes the actual number could be much higher.  This is a problem that won’t just go away.  Wells don’t leak for a year and then stop.  They can continue to leak for a century or more.  Cleaning up and plugging an abandoned well runs from $20,000 to $145,000, meaning that countrywide, cleaning up this environmental menace could cost somewhere between $60 billion and $435 billion.

**********

Web Links

Special Report: Millions of abandoned oil wells are leaking methane, a climate menace

Photo, posted October 13, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Environmental Injustice And the Coronavirus | Earth Wise

By Leave a Comment

Cities and towns across the United States continue to wrestle with the devastating impacts of the COVID-19 pandemic and none have been hit harder than low-income and minority communities.  Places like Detroit, Chicago, and St. James Parish in Louisiana have suffered from decades of economic inequality and pollution in their poorest neighborhoods and many of these same places have experienced some of the highest mortality rates from the virus.

Recent studies have shown a link between high levels of pollution and the risk of death from COVID-19.  Pollution of various kinds are higher in low-income communities and communities of color.  Such communities don’t have a strong political voice so that laws and environmental regulations are not enforced like there are in white, higher-income communities.  Thus, these communities have highways, landfills, factories, chemical facilities, paper mills, and other pollution sources that communities with economic power – and therefore political power – manage to avoid.

People living in low-income communities and communities of color tend to have higher rates of underlying health conditions like diabetes, heart disease, and asthma.  They have less healthy diets – more fast food and fewer grocery stores.  Part of the reason these communities have a higher risk of mortality from COVID-19 infection is that many people have reduced lung capacity as a result of exposure to pollutants.

The Trump administration has been suspending enforcement of environmental regulations during the pandemic.  Communities already affected by environmental injustice will bear the brunt of this decision.  Groups like nursing home populations, meat packers, prisoners and the poor are suddenly highly visible.  COVID-19 is exposing the real differences between the Haves and the Have-Nots in this country.

**********

Web Links

Connecting the Dots Between Environmental Injustice and the Coronavirus

Photo, posted May 2, 2006, courtesy of Sean Benham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Victory For Clean Water | Earth Wise

By Leave a Comment

Many of the nation’s environmental laws are under siege from the current administration, but a recent decision by the U.S. Supreme Court has solidified the Clean Water Act’s place as one of the country’s most effective environmental laws.

The case in question was about whether a wastewater treatment plant in Maui has been violating the Clean Water Act by polluting the ocean indirectly through groundwater.  Since the 1980s, the Lahaina wastewater treatment facility has been discharging millions of gallons of treated sewage each day into groundwater that reaches the waters off of Kahekili Beach, which is a popular snorkeling spot.   Groundwater, like any water beneath the land’s surface, can flow into major waterways such as rivers, streams, and, in this case, the ocean. 

In 2012, the nonprofit Earthjustice sued Maui county on behalf of four Maui community groups. Over the years, the Hawaii district court and the 9th Circuit appeals court ruled in favor of Earthjustice.  Last year, Maui County successfully petitioned the U.S. Supreme court to hear the case, which could have endangered the Clean Water Act.

On April 23, by a 6-3 vote, the court ruled that point source discharges to navigable waters through groundwater are regulated by the Clean Water Act when the addition of pollutants through groundwater is the functional equivalent of a direct discharge into navigable waters.

With this ruling, the Court rejected the Trump administration’s polluter-friendly position in the clearest of terms.  According to the opinion, written by Justice Breyer, the Court could not see how Congress could have intended to create such a large and obvious loophole in one of the key innovations of the Clean Water Act.  This is a victory for clean water.

**********

Web Links

The Clean Water Case of the Century

Photo, posted June 30, 2018, courtesy of Kirt Edblom via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lake George Health Report

By Leave a Comment

The Offshore Chemistry Program, run by the Darrin Fresh Water Institute at RPI, has been monitoring the deep waters of Lake George in New York for 40 years.  Lake George, nicknamed the Queen of American Lakes, is famed for the transparency of its water and a new report on the health of the lake reveals that it is doing rather well.

According to the report, although concentrations of chemicals and pollutants like salt and nutrients have increased in the deep waters of Lake George, they are still too low to harm the ecosystem at those depths.

The Offshore Chemistry Program studies the lake as part of a collaboration between RPI, IBM Research, and the FUND for Lake George that is called the Jefferson Project.  This long-term commitment provides a wealth of information over time matched by few lake studies in the world.

The recent results show that levels of salt, the nutrient orthophosphate, and chlorophyll have increased substantially over time, but none are yet at a level that will cause harm.

Orthophosphate occurs naturally, but most likely the higher levels are due to improperly functioning septic systems, failing wastewater treatment systems, and stormwater runoff.  The orthophosphate most likely triggered the increase in chlorophyll, which probably is associated with increased density of chlorophyll in individual algal cells, rather than an increase in total algal mass in the lake.

Overall, the results demonstrate the continuing resilience of Lake George to a growing array of stressors.  In nearly 40 years of human activities, the lake has changed in a number of ways, but the changes have so far been relatively small.  With such careful monitoring, we can hope to keep them that way.

**********

Web Links

Four Decades of Data Sounds Early Warning on Lake George

Photo, posted September 24, 2009, courtesy of GPA Photo Archive via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Breaking Down Forever Chemicals

By Leave a Comment

One of the toughest classes of pollutants are per- and polyfluoralkyl substances, or PFAS, as they are known.  PFAS are often called “forever chemicals” because they are extremely long-lasting and difficult to clean up.  They are found in household products including non-stick pans, dental floss, water-repellent fabrics, and many others.  They can be found extensively in U.S. waterways and soil.

PFAS move through the food chain, accumulating in humans at levels that scientists say can cause adverse health effects.  While these have not been definitively proven, there is evidence that higher cholesterol levels, cancer, thyroid disruption, and low infant birth rates are all associated with PFAS ingestion.

PFAS are difficult to get rid of because their carbon-fluorine covalent bonds are some of the strongest in organic chemistry.  Researchers at Princeton University have been studying a process known as Feammox in which ammonium breaks down in acidic, iron-rich soils in New Jersey wetlands and similar locations.  They found that this reaction takes place when a bacterium called Acidimicrobium A6 is present.

Using gene-sequencing techniques, they found that the microbe has characteristics that could help break down carbon-fluorine bonds, and therefore break down PFAS.  In tests using microbe-loaded soil samples, they found that the bacterium removed 60% of PFAS pollutants within 60 days.

The research has been published in the journal Environmental Science and Technology and the team is now testing the bacterium’s effectiveness over different time-spans in lab conditions before testing it in the field.

**********

Web Links

New Jersey Soil Microbe Shown to Break Down ‘Forever Chemicals’

Photo, posted November 9, 2017, courtesy of the Department of Environmental Quality 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.

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

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

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

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

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

**********

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.

High-Tide Flooding And Pollution

By Leave a Comment

Global sea levels are steadily rising.  They are up 8 inches in the past century and now increasing at an average of 1.3 inches per decade.  As a result, the incidence of high-tide “sunny day” flooding is on the rise, especially along the U.S. East Coast.

Norfolk Virginia experienced fewer than 2 days of high-tide flooding a year in the 1960s; it had 14 in 2017.  Up and down the East Coast, flood days have increased by factors of 5 and more.

This has led to a form of pollution that hasn’t gathered much attention in the past:  when these floodwaters recede, they can carry debris, toxic pollutants and excess nutrients into rivers, bays, and oceans.

In the aftermath of high-tide flooding in Norfolk, Chesapeake Bay was littered with tipped-over garbage cans, tossed-away hamburgers, oil, dirty diapers, pet waste and all manner of other things.  Water that comes up on the landscape takes everything back into the river or ocean with it.

Analysis of tidal flooding along the Lafayette River in Norfolk indicated that just one morning of tidal flooding poured nearly the entire EPA annual allocation of nitrogen runoff for the river – nearly 2,000 pounds – into Chesapeake Bay.  The effects of excess nitrogen in the water are well-known and responsible for the toxic algal blooms that endanger aquatic life as well as human health.

According to the National Oceanic and Atmospheric Administration, high-tide flooding frequency along the southeastern coast of the U.S. rose 160% since 2000.  With the expected continuing rises in sea level, NOAA projects that as many as 85 days of high-tide flooding will occur along the coast by the year 2050.  It’s a big problem.

**********

Web Links

As High-Tide Flooding Worsens, More Pollution Is Washing to the Sea

Photo, posted September 20, 2018, courtesy of SC National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sustainable Plastics

By Leave a Comment

According to the United Nations, plastic accounts for up to 90% of all the pollutants in the ocean. Conventional plastics take hundreds of years to decay, so all the plastic that gets into the oceans piles up and endangers marine life and pollutes the environment. Unfortunately, there are few comparable, environmentally friendly alternatives.  

An often-proposed solution is bioplastics, which are not made from petroleum and degrade quickly.  The downside of bioplastics is that growing the plants or bacteria used to make the plastic requires fertile soil and fresh water, which are scarce commodities in many places.

One such place is Israel.  So, researchers there at Tel Aviv University have developed a process to make a bioplastic polymer that doesn’t require land or fresh water.  The new polymer is derived from microorganisms that feed on seaweed.  It is biodegradable, produces zero toxic waste and recycles into organic waste.

The polymer is called polyhydroxyalkanoate, or PHA for short.  The raw material is multicellular seaweed, cultivated in the ocean.  These algae are eaten by single-celled microorganisms, which also grow in salty seawater and produce a polymer that can be used to make bioplastic.  PHA is already produced in commercial quantities, but it is currently made from plants that require agricultural land and fresh water.  The new process would enable countries with limited fresh water, such as Israel, China and India, to switch from petroleum-based plastics to biodegradable plastics.

Plastics from fossil sources are one of the world’s biggest pollution problems.  The new study shows that it is possible to produce bioplastic completely based on marine resources in an environmentally-friendly process. 

**********

Web Links

Sustainable ‘plastics’ are on the horizon

Photo, posted March 14, 2015, courtesy of 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...)