debris

Death Valley Flooding | Earth Wise

September 13, 2022 By EarthWise Leave a Comment

Furnace Creek in Death Valley is the driest place in North America. Its average annual rainfall is under two inches. On August 5th, a thousand-year rainfall event dropped 1.46 inches of rain – about three-quarters of a year’s precipitation. The all-time record for a single day is 1.47 inches, set in April 1988. The storm did break the record for the most rain ever recorded in August, which averages just over a tenth of an inch of rain for the entire month.

The flash flood washed debris over roads, swept away and buried cars, knocked a water facility offline, damaged buildings, and stranded about a thousand visitors and staff in Death Valley National Park. By the next day, the flood water had mostly receded, and stranded visitors could be escorted out of the park by National Park personnel.

Death Valley sits at 282 feet below sea level. If it were not for the extremely arid climate there, Death Valley would likely be filled with water. However, humid air masses traveling east from the Pacific Ocean have to cross four mountain ranges before they reach the desert valley. Those air masses lose their moisture in the form of rain on the western slopes of the mountain, leaving a dry area, or rain shadow, on the eastern sides. By the time the air masses reach Death Valley, they are bone dry. On rare occasions, the lowest spot in the valley fills with water forming a wide, shallow lake, known as Lake Badwater.

The extreme heat and aridity of Death Valley evaporates the temporary lake quickly, returning the valley to its usual state. Furnace Creek still holds the record for the highest air temperature ever recorded: 134 degrees Fahrenheit.

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Death Valley Flash Flooding

Photo, posted April 7, 2021, courtesy of Matthew Dillon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Humans And Microplastics | Earth Wise

April 13, 2022 By EarthWise Leave a Comment

While plastic comes in all different shapes and sizes, those that are less than five millimeters in length are called microplastics. Primary sources of microplastics include microfibers from clothing, microbeads, and plastic pellets (known as nurdles). Secondary sources of microplastics come from larger plastic debris, like bottles and bags, that degrades into smaller bits over time.

Microplastic pollution can be found everywhere on earth, from the top of the tallest mountains to the bottom of the deepest oceans. Microplastics are in the food we eat, the water we drink, and the air we breathe.

According to research recently published in the journal Exposure & Health, humans ingest an average of five grams of plastic particles per week. This is roughly equivalent to the weight of a credit card. The plastic particles are trafficked in via food, such as seafood and salt in particular, as well as water. In fact, those who rely on plastic bottled water for their drinking needs ingest an additional 1,700 plastic particles each week.

Microplastics have also been detected in human blood for the first time. According to new research recently published in the journal Environment International, scientists detected microplastics in nearly 80% of the people they tested.

Half of the blood samples contained PET plastic, which is commonly used for drinking bottles. One third of the blood samples contained polystyrene plastic, which is often used for food packaging. One quarter of the blood samples contained polyethylene plastic, which is used to make things like shopping bags and detergent bottles.

With plastic production predicted to double by 2040, more research is urgently needed to understand how ingesting microplastics affects human health.

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Health risk due to micro- and nanoplastics in food

Microplastics found in human blood for first time

Discovery and quantification of plastic particle pollution in human blood

Photo, posted November 3, 2012, courtesy of Laura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bomb Cyclones | Earth Wise

December 2, 2021 By EarthWise Leave a Comment

It seems like we are hearing about new weather phenomena pretty frequently these days. One name that has popped up lately is “bomb cyclones.” Bomb cyclones, it turns out, are storms that undergo “bombogenesis.” What that means is a low-pressure area (in other words, a storm) that undergoes rapid strengthening and can be described as a weather bomb, or popularly, a bomb cyclone.

These things usually take place over remote tropical ocean areas but a really intense one struck the Pacific Northwest on October 24th. The storm off the coast of Washington, with a barometric pressure reading equivalent to a category 4 hurricane, was the second extreme low-pressure storm in the North Pacific in a single week. Both storms involved pressure drops of more than 24 millibars in 24 hours, making them bomb cyclones.

These storms brought high winds and extreme precipitation that doused wildfires and provided some relief to the extreme drought in Central and Northern California. Along with these positive effects, however, the storms also caused power outages, flooding, landslides, and mud and debris that washed out roads.

The October 24-25 event brought 16.55 inches of rain to Mount Tamalpais in Marin County, California in a 48-hour period. Sacramento got 5.44 inches of rain, breaking a 140-year-old record. And the city had just broken another extreme weather record for the longest dry spell in history.

The storms directed streams of moisture from north of Hawaii toward the West Coast in long, narrow bands of moisture known as atmospheric rivers. We are learning about all sorts of unfamiliar weather phenomena as extreme weather events become increasingly common.

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Extratropical Cyclones Drench West Coast

Photo, posted January 4, 2018, courtesy of NOAA/CIRA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Ways To Make Bioplastics | Earth Wise

August 27, 2021 By EarthWise Leave a Comment

The world produces over 300 million tons of plastics each year, mostly produced from petroleum. The environmental consequences are substantial and there is a critical need to replace as much of that plastic production with biodegradable plastics as possible. Thus, there is global research aimed at making bioplastics more economical and as environmentally friendly as possible.

Researchers at Texas A&M University have developed an improved approach for making bioplastics from corn stubble, grasses, and mesquite agricultural production. Apart from the obvious environmental benefits of having biodegradable plastics, producing bioplastics from common agricultural waste would create new revenue streams for farmers as well as the people who transport harvested feedstock and byproduct crops to refinery operations.

The key to bioplastic production is the efficient extraction and use of lignin, the organic polymer that is the primary structural support material in most plants. The new research takes five conventional pretreatment technologies for plant materials and modifies them to produce both biofuel and plastics together at a lower cost. The new method is called “plug-in preconditioning processes of lignin” and it can be directly and economically added into current biorefineries. The process is designed to integrate dissolving, conditioning, and fermenting lignin, extracting energy from it and making it easily adaptable to biorefinery designs.

The so-called bioeconomy currently supports some 286,000 jobs. Innovation is the key to achieving more widespread use of biodegradable plastic. With improved economics of so-called lignocellulosic biorefineries, there can be new avenues to use agricultural waste to produce biodegradable plastics.

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‘Plugging in’ to produce environmentally friendly bioplastics

Photo, posted November 5, 2015, courtesy of Kathryn Faith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tracking Ocean Plastics | Earth Wise

July 30, 2021 By EarthWise Leave a Comment

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

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

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

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

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Ocean microplastics: First global view shows seasonal changes and sources

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

Earth Wise is a production of WAMC Northeast Public Radio.

Marine Debris | Earth Wise

July 8, 2021 By EarthWise Leave a Comment

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

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

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

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

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

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Lives and Livelihoods Disrupted by Marine Debris

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

Earth Wise is a production of WAMC Northeast Public Radio.

Paving With Plastic | Earth Wise

March 25, 2021 By EarthWise Leave a Comment

The country of Ghana has an ambitious plan to recycle and reuse as much plastic waste as it produces each year (which is over a million tons) by 2030. As part of this plan, they have started to pave roads in Accra, the capital city, with asphalt containing a slurry of used plastics – shredded and melted bags, bottles, and snack wraps. Only a quarter of Ghana’s roads are currently paved, so waste plastic has many opportunities for use in paving.

Plastic roads first appeared in India two decades ago. There are now over 60,000 miles of them in that country. Several countries have only recently built their first plastic roads including South Africa, Vietnam, Mexico, the Philippines, and the United States.

Studies have shown that roads containing waste plastic have the potential to perform as well or better than traditional roads. They can last longer, can tolerate wide temperature swings better, are stronger and more durable, and are more resistant to water damage, cracking, and potholes.

Ordinarily, asphalt for roads consists of 90 to 95% aggregate – typically some mixture of gravel, sand, and limestone – and 5 to 10% bitumen, which is a black gooey substance extracted from crude oil that binds the aggregate together. Plastic-enhanced roads replace varying amounts of the bitumen (often as little as 4-10%, but sometimes much more), with plastic that is actually a stronger binding agent.

Plastic roads reduce the amount of bitumen in roads, thereby reducing carbon emissions. The plastics are not heated enough to release gases and the roads do not appear to shed microplastics. Plastic roads will not solve the world’s plastic waste problem, but they can help by diverting lots of plastic from landfills.

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How Paving with Plastic Could Make a Dent in the Global Waste Problem

Photo, posted June 4, 2010, courtesy of Sustainable Initiatives Fund Trust via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mollusks And Microplastics | Earth Wise

January 26, 2021 By EarthWise Leave a Comment

Plastic debris comes in all different shapes and sizes, but pieces that are less than five millimeters in length are called microplastics. Microplastics are everywhere, including in the food we eat, the water we drink, and the air we breathe.

Much of the oceanic microplastic pollution comes from the breakdown of plastic litter. Another source of microplastic pollution is microbeads. Microbeads, which are sometimes added to cleansing and exfoliating personal care products, pollute the environment when they get flushed down the drain.

According to a new study by researchers at Hull York Medical School and the University of Hull in the U.K., mussels, oysters and scallops have the highest levels of microplastic contamination among seafood. The research team examined 50 studies between 2014 and 2020 to determine the levels of microplastic contamination globally in fish and shellfish. The team found that microplastic content was 0-10.5 microplastics per gram in mollusks, 0.1-8.6 microplastics per gram in crustaceans, and 0-2.9 microplastics per gram in fish.

The researchers found that mollusks collected off the coasts of Asia were the most heavily contaminated with microplastics. China, Australia, Canada, Japan and the United States are among the largest consumers of mollusks, followed by Europe and the U.K.

While the human health implications of consuming microplastics are not well understood, early evidence from other studies suggest they do cause harm.

According to the research team, more data is needed from different parts of the world in order to better understand how microplastics vary between different oceans, seas, and waterways.

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Highest levels of microplastics found in molluscs, new study says

Photo, posted September 3, 2007, courtesy of Andrew Malone via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Compost And Landfills | Earth Wise

January 19, 2021 By EarthWise Leave a Comment

Composting is popular as a way to keep solid waste out of landfills and many people turn much of their kitchen waste into rich soil amendments. Cities and towns across the country have composting programs that collect waste from residents to produce large quantities of compost rather than adding the waste to landfills. A new study from North Carolina State University looked into the environmental benefits of actually using compost at landfills.

Most municipal composting programs require that the compost they produce gets used “beneficially”. The new research shows that using compost as an alternative daily cover at landfills is competitive and often superior to the use of compost as a soil amendment in terms of its environmental benefits.

Landfills apply a layer of daily cover to reduce odors, reduce windblown debris, and keep vermin out of landfill waste. Federal regulations require six inches of soil as a daily cover.

Compost from food waste in particular is not always suitable for soil amendment in gardens and agricultural fields because it often contains broken glass and other contaminants.

The North Carolina State study looked at the environmental impact of using compost as daily cover in landfills compared with its use as a soil amendment. They looked at global warming potential, acidification potential, eutrophication (which is the amount of nutrients released to ground and surface water), cumulative energy demand, and the depletion of resources.

The study concluded that using compost as landfill daily cover is environmentally superior with regard to eutrophication, acidification, and global warming potential. On the other hand, soil amendment was better in terms of resource depletion and cumulative energy demand.

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Applying Compost to Landfills Could Have Environmental Benefits

Photo, posted April 22, 2008, courtesy of Alachua County via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Value From Plastic Waste | Earth Wise

November 30, 2020 By EarthWise Leave a Comment

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

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

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

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

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

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Turning plastic waste into hydrogen and high-value carbons

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

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastics And Florida’s Birds of Prey | Earth Wise

June 19, 2020 By EarthWise Leave a Comment

Plastic debris comes in all different shapes and sizes, but those that are less than five millimeters in length are called microplastics. Some microplastics come from larger plastic debris that degrades into smaller bits over time. Another type of microplastics – called microbeads – are intentionally manufactured tiny plastic beads that are added as exfoliants to some health and beauty products.

According to a new study published in the journal Environmental Pollution, researchers have confirmed and quantified the presence of microplastics in terrestrial and aquatic birds of prey in Florida for the first time. This research is important because these birds of prey, including ospreys, hawks, and owls, are critical to maintaining a healthy ecosystem. The accumulation of microplastics in their digestive systems could lead to a myriad of health issues, including starvation.

Working with the Audubon Center for Birds of Prey in Florida, the research team from the University of Central Florida was able to examine the stomachs of 63 deceased birds. The team found microplastics in every bird it examined, extracting nearly 1,200 pieces of plastic in total. Microfibers represented 86% of the plastic pieces.

It’s common for plastic microfibers to enter ecosystems through the wastewater from washing machines. A 2016 study found that 700,000 plastic fibers come off in a typical wash. While there are lots of variables, synthetic fabrics account for 60% of the material used in clothing worldwide.

To help cut down on plastic in the environment, the research team suggests removing plastics from open landfills, purchasing only natural fabrics and clothing, and modifying water treatment facilities to capture microplastics.

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Microplastics found in Florida’s birds of prey for first time

Photo, posted April 15, 2016, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

June 4, 2020 By EarthWise Leave a Comment

Many of us are aware of the infamous ocean “garbage patches” of floating plastic. The Great Pacific Garbage Patch is roughly the size of Texas. But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total. The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around. One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor. This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets.

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents. These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity. Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom. As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mistaking Plastic For Food

September 27, 2019 By EarthWise Leave a Comment

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

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

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

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

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

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

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Green turtles eat plastic that looks like their food

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

Earth Wise is a production of WAMC Northeast Public Radio.

High-Tide Flooding And Pollution

April 30, 2019 By EarthWise 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.

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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.

Balloons And Seabirds

March 19, 2019 By EarthWise Leave a Comment

It’s no secret that there is a ton of plastic in the ocean – millions of tons, in fact. Scientists estimate that there is more 165 million tons of plastics swirling about in our oceans today, with an additional 8.8 million tons flowing in every year. As the oceans swell with plastic debris, many marine species wind up ingesting the stuff – often with dire consequences.

All this plastic trash winds up affecting more than just aquatic species, too. According to researchers from the University of Tasmania, a seabird that ingested a single piece of plastic has a 20% chance of mortality. This statistic jumps to 50% if the seabird consumes nine pieces of plastic.

The study, which was recently published in the journal Scientific Reports, also found that while hard plastics account for the majority of plastic debris ingested, it’s far less likely to prove fatal than soft plastics, such as balloons.

In fact, the researchers found that balloons or balloon fragments were the number one marine debris risk of mortality for seabirds, killing almost one in five of the seabirds that ingested them.

The leading cause of death among the seabirds studied was blockage of the gastrointestinal tract. While soft plastics only accounted for 5% of the ingested plastics, they were responsible for more than 40% of seabird mortality. But the researchers make clear that hard plastics were still responsible for more than half of the study’s seabird deaths.

If we want to reduce the number of marine species dying from plastic ingestion, we need to reduce the volume of plastic going into the ocean and do what we can to remove what’s already there.

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