FOREVER CHEMICALS

Garden produce grown near Fayetteville works fluorochemical plant contains GenX, other PFAs

North Carolina State University

Residential garden produce grown near the Fayetteville Works fluorochemical plant can expose those who consume it to per- and polyfluoroalkyl substances (PFAS), according to a new study conducted by researchers from North Carolina State University, East Carolina University and the Colorado School of Mines.

“It is often assumed that contaminated drinking water is the main pathway through which we are exposed to PFAS,” says Detlef Knappe, professor of civil, construction, and environmental engineering at NC State and a lead investigator of the study. “An important goal of our study was to determine whether people who live in PFAS-impacted communities are also exposed to PFAS through home-grown produce.”

The researchers collected 53 produce samples from five residential gardens located near the fluorochemical manufacturer Fayetteville Works in Fayetteville, N.C. Samples were analyzed for 43 PFAS. The targeted PFAS included GenX and 12 other per- and polyfluoroalkyl ether acids (PFEAs) that are uniquely associated with the Chemours-owned facility.

The summed PFAS concentrations detected in as-received produce reached up to 38 nanograms per gram (ng/g), with PFEAs from the manufacturer overwhelmingly dominating the PFAS profile.

Among different types of produce studied, which included fruits, vegetables, and nuts, researchers found that water-rich produce, like berries and figs, exhibited the highest PFAS levels. When comparing frozen produce harvested in the area over time, researchers observed a general decreasing trend in PFAS levels from 2013 to 2019, though with some variations. While the exact cause of this decline is unclear, researchers suspect that interventions implemented to reduce air emissions at the nearby fluorochemical manufacturer might have played a role.

Next, the researchers looked at how PFAS exposure through consuming contaminated produce compared to exposure through drinking water. Specifically, researchers determined how much produce would give the same exposure to GenX as drinking water with 10 ng/L of GenX, the highest level allowed by the U.S. Environmental Protection Agency (EPA).

“The comparison was made based solely on GenX because it was the only one of the detected PFEAs for which toxicity information was available,” says Pingping Meng, assistant professor of chemistry at ECU and lead author of this study.

For the site with the highest average GenX concentration in the studied produce (0.19 ng/g), the researchers found that for children, daily exposure to GenX from drinking water containing 10 ng/L GenX is similar to eating about 17 g (0.6 ounces, or about 10 blueberries) and adults eating about 68 g (2.4 ounces) of produce. These produce quantities are about nine times lower for children and four times lower for adults than the typical intake of fruits and vegetables.

To assess the long-term risk of consuming GenX-contaminated produce in impacted communities, researchers also calculated the chronic-exposure daily limit, which is the maximum amount of produce that an individual could safely consume daily.

For children aged 3 to 6 years, the daily limit for chronic exposure was 289 grams daily (about 10 ounces, or one and two-thirds cups of blueberries), which is higher than the typical value of 186 grams per day. However, the researchers note that the risk from consuming this amount of produce is likely underestimated because the calculation didn't consider other PFAS in the produce.

“We may be underestimating the risk because we are not considering the potentially additive effects of PFEA mixtures, particularly for PFEAs that were detected at concentrations higher than GenX but for which health-based reference doses are lacking,” Meng says. “Research is urgently needed to better understand the toxicity of the dominant PFEAs that we detected in the produce.”

“Our results show that people who live near Fayetteville Works and consumed locally grown fruits and vegetables were exposed to numerous PFEAs through their diet,” adds Knappe. “These findings highlight that diet, in addition to drinking water, can be an important human exposure pathway.”

The study, “Residential Garden Produce Harvested Near a Fluorochemical Manufacturer in North Carolina Can be an Important Fluoroether Exposure Pathway” appears in the Journal of Agricultural and Food Chemistry and was supported by the U.S. EPA [Grant R839482: U.S. National Investigation of Transport and Exposure from Drinking Water and Diet (PFAS UNITEDD)] and the North Carolina Collaboratory. NC State co-authors include Nadia Sheppard, Sarangi Joseph and Owen Duckworth. Christopher Higgins of the Colorado School of Mines also contributed to the work.

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Note to editors: An abstract follows.

“Residential garden produce harvested near a fluorochemical manufacturer in North Carolina can be an important fluoroether exposure pathway”

DOI: 10.1021/acs.jafc.4c06177

Authors: Pingping Meng, East Carolina University; Nadia Sheppard, Sarangi Joseph, Owen W. Duckworth, Detlef R. U. Knappe, North Carolina State University; Christopher P. Higgins, Colorado School of Mines

Published: Nov. 20, 2024 in the Journal of Agricultural and Food Chemistry

Abstract:
Dietary intake can be an important exposure route to per- and polyfluoroalkyl substances (PFASs). Little is known about the bioaccumulation of emerging per- and polyfluoroalkyl ether acids (PFEAs) in garden produce from PFAS-impacted communities and the associated dietary exposure risk. In this study, fifty-three produce samples were collected from five residential gardens near a fluorochemical manufacturer. Summed PFAS concentrations ranged from 0.0026 to 38 ng/g wet weight of produce, and water-rich produce exhibited the highest PFAS levels. The PFAS signature was dominated by PFEAs, and hexafluoropropylene oxide-dimer acid (commonly known as GenX) was detected in 72% of samples. Based on average measured GenX concentrations, chronic-exposure daily limits were as low as 289 g produce/day for children (3-6 yr). This analysis does not consider other PFEAs that were present at higher concentrations, but for which reference doses were not available. This study revealed that consuming residential garden produce grown in PFAS-impacted communities can be an important exposure pathway.

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Journal

Journal of Agricultural and Food Chemistry

DOI

10.1021/acs.jafc.4c06177 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Residential garden produce harvested near a fluorochemical manufacturer in North Carolina can be an important fluoroether exposure pathway

Article Publication Date

20-Nov-2024

Chemistry paper discusses new approach to breakdown PFAS, forever chemicals

Researchers have found a new approach for breaking down a group of human-made chemicals that can carry health risks from long-term exposure

Colorado State University

 

image: 

Garret Miyake

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Credit: Colorado State University College of Natural Sciences/John Cline

Researchers at Colorado State University have found a new approach for breaking down PFAS – a group of human-made “forever” chemicals commonly used for their water-resistant properties that can carry health risks from long-term exposure. 

The carbon-fluorine bond found in PFAS (perfluoroalkyl and polyfluoroalkyl substances) compounds is particularly challenging to break apart. That durability has led to widespread use of these manufactured chemicals in medical, industrial and commercial settings. However, that inherent stability has also made them difficult to dispose of, and over time, they have made their way into water, air and soil across the world according to the Environmental Protection Agency. The EPA says exposure to these lingering compounds can lead to health problems, including cancer or reproductive issues. 

In a paper published today in Nature, CSU researchers showcase an effective LED light-based photocatalytic system that can be used at room temperature to break down those key carbon-fluorine bonds. The system is an improvement over traditional chemical manufacturing processes that typically require high temperatures to achieve similar results.  

Work at CSU was led by Professor Garret Miyake in the Department of Chemistry. His team partnered with fellow CSU chemistry Professor Robert Paton as well as Professor Niels Damrauer at the University of Colorado Boulder on the paper. 

Miyake said complimentary expertise across those teams led to this high-impact interdisciplinary research finding.  

“Our approach is a fundamental advancement in organic synthesis that achieves activation of these challenging carbon-fluorine bonds across a variety of situations,” he said. “Our method is more sustainable and efficient and can be used to address stubborn compounds in plastics, for example, in addition to the obvious uses around PFAS.” 

Most people in the world have been exposed to PFAS by touching or eating materials containing them. A common source of exposure is drinking water, but the compounds can also be found in non-stick consumer products, food packaging, and common manufacturing processes. Research led by the EPA shows that even low-level exposure can result in developmental effects like low birth weight or reduced immune response, among many other health issues. 

Postdoctoral researcher Mihai Popescu served as an author on the paper and contributed to the mechanistic understanding of the research using computational chemistry. He said the next challenge will be in taking the technology and preparing it for application in the field across many instances. 

“We need to make this technology more practical so it can be used in water or soil – places where PFAS are found,” said Popescu. “We need the chemistry we are showcasing here to be useful in those conditions and that is where a lot of work remains.” 

Miyake currently serves as director of the National Science Foundation funded Center for Sustainable Photoredox Catalysis (SuPRCat) on campus. That center launched in 2023 with a goal of developing chemical manufacturing processes that harness light energy and utilizing readily available materials as catalysts. 

Miyake noted that similar research projects to the one discussed in the paper are happening every day through the center. Postdoctoral researcher Xin Liu – who lead the synthetic development of this work and is also a member of SuPRCat – said the work holds many possibilities. 

“This paper deals specifically with forever chemicals, but our approach in SuPRCat to using LED lights presents a host of possibilities towards achieving these reactions in a more sustainable and efficient way,” said Liu. “From dealing with plastics that don’t degrade quickly to improving the manufacturing process of needed fertilizers, this is a key area and something CSU is well positioned to lead on.” 

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Journal

Nature

DOI

10.1038/s41586-024-08327-7 

Article Title

Photocatalytic C‒F bond activation in small molecules and polyfluoroalkyl substances

Article Publication Date

20-Nov-2024

Study tracks PFAS, microplastics through landfills and wastewater treatment plants

Contaminants end up in biosolids, which are sprayed on croplands as fertilizer

University of Illinois at Urbana-Champaign, News Bureau

 

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Microplastics and PFAS flow into wastewater treatment plants from landfill leachate, left, and from storm and sanitary sewers. Both contaminants accumulate in biosolid waste, most of which is carted out and spread on agricultural fields. On the right, a sample of the microplastics recovered from wastewater treatment plants in Illinois.

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Credit: Photo by Fred Zwicky

CHAMPAIGN, Ill. — Scientists analyzed the liquid waste, or leachate, released by four Illinois landfills and the inflows and outflows of associated wastewater treatment plants to determine the fate of two contaminants: microplastics and per- and polyfluoroalkyl substances, or PFAS.

The good news from the study is that landfills retain most of the plastic waste that is dumped there, and wastewater treatment plants remove 99% of the microplastics and a some of the PFAS from the wastewater and landfill leachate they take in. The bad news is that both microplastics and PFAS accumulate in the biosolids that settle to the bottom of wastewater treatment plants. These biosolids must be disposed of in other ways.

The findings are reported in the journal Science of the Total Environment.

According to the industry-funded National Biosolids Data Project, 70% of the biosolids from Illinois wastewater treatment plants are used as fertilizers on agricultural land, and 30% are buried in landfills. This means that most of the microplastics and PFAS that flow into wastewater treatment plants are going right back into the environment, said John Scott, a research scientist at the Illinois Sustainable Technology Center at the University of Illinois Urbana-Champaign who led the study with fellow ISTC research scientist Andres Prada.

“The wastewater treatment plants are just taking the contaminants from one media and putting it into another,” Scott said.

Several hundred million tons of plastics are produced each year globally, and an estimated 79% of this material ends up in landfills or “becomes fugitive in the environment,” the researchers wrote in their report. Both microplastics and the endocrine-disrupting chemicals known as PFAS are now ubiquitous: detected in soil, water and in the human body, they said.

The new study is unusual in that it calculated the mass of microplastics in landfill leachate and wastewater influent and effluent. Most studies simply count the number of microplastic particles per volume of liquid, an unreliable measure because the particles will keep breaking into smaller bits, Prada said. To get the mass, the team measured the total surface area of the plastic particles and incorporated a standard measure of thickness and density based on the most common microplastic waste types: polyethylene and polypropylene.

“Landfills and wastewater treatment plants are usually studied separately, but in reality, those are combined systems,” Prada said. “Regulations require that landfills send their liquid waste to the treatment plants.”

And many studies look at only one contaminant at a time, he said.

“We wanted to put everything together, look at both systems and give results for both contaminants,” Prada said.

The analysis revealed that while landfills do a good job of retaining microplastics, their leachate contains high levels of PFAS.

“We were surprised how high the PFAS levels were in landfill leachate, while the microplastics were lower than expected,” Prada said.

While plastics degrade more slowly in landfills due to the compression of waste and the lack of solar radiation once they’re buried, the plastics will continue to break down into smaller particles, which will eventually flow out with the leachate, Scott said.

Wastewater treatment plants are designed to take in thousands of gallons of wastewater from sanitary and storm sewer systems, and that water also carries a significant load of microplastics and PFAS. While the concentration of PFAS in water flowing through these systems is lower than that found in landfill leachate, the massive volume of water coming in from sewers brings in a higher overall load of both contaminants, the team reported.

Wastewater treatment plants can take in 10,000 gallons of wastewater per minute but only about 30,000 gallons of landfill leachate per day, Prada said.

The problem of microplastics and PFAS in biosolids is not easy to solve, the researchers said. Spreading PFAS and microplastics across cropland is not a good practice, Scott said. “But what else are we to do with it? If we landfill it, we’re just going around and around in the circle of moving it from landfill to wastewater treatment plant and back to the landfill.”

Trying to treat the biosolids before disposal is a very expensive prospect, Scott said. The best practice would be to prevent the problem of plastic and PFAS pollution further upstream, he said.

“It’s time to tell people to start moving away from these things, stop producing these things,” Scott said. “Let’s turn them off at the tap before this gets any worse.”

This research was funded by the Hazardous Waste Research Fund, which is administered by the ISTC, a part of the Prairie Research Institute at the U. of I.

The paper “Microplastics and per- and polyfluoroalkyl substances (PFAS) in landfill-wastewater treatment systems: A field study” is available online or from the U. of I. News Bureau.

DOI: 10.1016/j.scitotenv.2024.176751

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Journal

Science of The Total Environment

DOI

10.1016/j.scitotenv.2024.176751 

Subject of Research

Not applicable

Article Title

Microplastics and per- and polyfluoroalkyl substances (PFAS) in landfill-wastewater treatment systems: A field study

 

World's first visual grading system developed to combat microplastic fashion pollution

Heriot-Watt University

 

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Dr Lisa Macintyre, associate professor of textiles at the Heriot-Watt University's School of Textiles and Design.

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Credit: Heriot-Watt University

Over 14 million tonnes of microplastics are estimated to be lying on the ocean floor with the fashion industry among the worst pollutants. 

 

But a new project led by textile experts at Heriot-Watt University in the Scottish Borders, is aiming to make fashion labels and consumers alike, more environmentally aware when manufacturing and buying new clothes. 

 

For four years, a small team headed by Dr Lisa Macintyre, associate professor of textiles at the University’s School of Textiles and Design in the Galashiels campus, has overseen painstaking research to co-develop the world’s first visual ‘fibre fragmentation scale’.

 

The five-point scale assesses the volume of fibre fragments shed from different clothing materials, with observers visually grading each between one and five. Grade one having the highest volume of shed fibres to grade five having the least.

 

This new method is faster and more cost effective when processing a large volume of materials than compared with alternative techniques. This holds significant advantages to manufacturers as they can quickly identify low shedding materials and select these for further testing to determine their suitability for garment production. Existing methods, such as those used by the International Organisation for Standardisation (ISO), are more expensive and time-consuming.

 

The findings have featured in a new paper, entitled, Low-cost, high-throughput quantification of microplastics released from textile wash tests: Introducing the fibre fragmentation scale, and published today in the peer-reviewed journal, Plastics.

 

Dr Macintyre said: “The microplastics problem is massive. Fashion and textiles is one of the biggest sources of secondary microplastics in the environment with fragments of plastic fibres, like polyester and nylon, being shed from clothing.

 

“There are fibre fragments absolutely everywhere, from icebergs to the deepest ocean to human lungs and our food, they’re in everything. 

 

“Visual scales are already used in the fashion industry to measure how much bobbling a material may suffer on its surface for example or, perhaps the most well-known is the grey scale, which measures colour fading or staining, but there was no such tool for fibre shedding. 

 

“This project aims to change that and allow manufacturers to not only make better choices in production but also to communicate to their customers in a very simple and straightforward way, the typical amount of fibres shed from a garment.”

 

Thousands of tiny fibres can be shed from some clothing through daily wear and tear, including laundry. They are typically very thin, ranging in size from a fraction of a millimetre to several centimetres in length. Despite their small size, they can inflict substantial harm on ecosystems, animals, and human health, potentially leading to cellular damage and inflammation.

 

In testing their new scale, the academics used a machine containing eight separate canisters, known as a ‘rotawash’.

 

Textile samples were placed within the canisters, filled with water and then churned to replicate a washing machine cycle. The wastewater was then filtered, allowing the testers and observers to visually grade the shed fibres against the scale.

Some 46 testers from the fashion industry, university students and the public volunteered in the project grading around 100 samples over two years.  

 

Sophia Murden is in her final year studying for a PhD in fibre fragmentation testing at Heriot-Watt University. She has been working alongside Dr Macintyre in developing the fibre fragmentation scale and says this is the first time that a visual scale has been developed. 

 

She said: “Our methodology is simple and cost effective. The filters used to collect fibre fragments from laundry wastewater can be graded against our five-point scale, which surprisingly is more accurate at assessing very low levels of fragmentation than the equivalent method of weighing fibres.

 

“The ultimate aim is for manufacturers to choose materials that are going to have the least impact on our environment but also allow consumers to make an informed decision when they buy their clothing.”

 

If adopted by industry, the fibre fragmentation scale could be displayed on clothing labels, similar to the way many UK food manufacturers display calorie information on packaging.

 

Dr Macintyre adds: “We’ve already been in contact with the likes of Helly Hansen and Lochcarron of Scotland who are very supportive of what we are doing.

 

“The next stage for us is to try and get some kind of industry agreement. Currently, we don’t have an ‘acceptable fragmentation’ rate for clothing but that’s not unusual. The environment is an important issue, and we’d want to get key industry leaders and policymakers to sit down and start agreeing standards, perhaps even legislating against high shedding materials.”

 

The project has been funded through the University’s James Watt Scholarship which is aimed at advancing research for the benefit of society. 

Dr Lisa Macintyre using the visual grading system in a lab.

The world's first visual ‘fibre fragmentation scale’.

Credit

Heriot-Watt University

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Journal

Cambridge Prisms Plastics

DOI

10.1017/plc.2024.30 

Article Title

Low-cost, high-throughput quantification of microplastics released from textile wash tests: Introducing the fibre fragmentation scale

Bio-based fibers could pose greater threat to the environment than conventional plastics

The research has led scientists to suggest that materials being advocated as alternatives to plastic should be tested thoroughly before they are used extensively in a range of products

University of Plymouth

 

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A new study in the journal Environmental Science and Technology tested the effects of conventional polyester fibres and two bio-based fibres –viscose and lyocell – on earthworms, a species critical to the health of soils globally

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Credit: Lloyd Russell/University of Plymouth

Bio-based materials may pose a greater health risk to some of the planet’s most important species than the conventional plastics they are designed to replace, a new study has shown.

Such materials are increasingly being advocated as environmentally friendly alternatives to plastics, and used in textiles and products including clothing, wet wipes and period products.

However, microfibres of the materials are emitted into the environment through the laundry cycle, the application of sewage sludge as fertilisers, or the simple wear and tear of textile products.

Despite increasing quantities of bio-based products being produced and sold all over the world, there has been little research to assess their potential impact on species and ecosystems.

To address that, a new study in the journal Environmental Science and Technology tested the effects of conventional polyester fibres and two bio-based fibres –viscose and lyocell – on earthworms, a species critical to the health of soils globally.

The study found that in high concentrations of fibres, 30% of earthworms died after 72 hours when exposed to polyester, while those exposed to the bio-based fibres experienced much higher mortality of up to 60% in the case of lyocell and 80% for viscose.

A second experiment, using environmentally relevant concentrations of the fibres, indicated that earthworms housed in soils containing viscose fibres exhibited reduced reproduction compared to those exposed to polyester fibres. Earthworms in the soils containing lyocell fibres showed reduced growth and also higher rates of burrowing within the soil compared to exposure to the other types of fibre.

The researchers say the study highlights the complex nature of global efforts to reduce the threat of microplastic pollution, and the importance of testing new materials being advocated as alternatives to plastics before they are released on the open market.

The study was carried out as part of the BIO-PLASTIC-RISK project, led by researchers at the University of Plymouth and the University of Bath, and supported with £2.6million funding by the Natural Environmental Research Council.

Dr Winnie Courtene-Jones, lead author on the new study and now a Lecturer in Marine Pollution at Bangor University, said: “Over 320,000 tonnes of bio-based and biodegradable fibres were produced globally in 2022 and research shows that substantial  quantities of that will end up in the environment. However, evidence of their ecological impacts has been lacking. Our study has shown that bio-based fibres have a range of adverse effects on earthworms – animals which are critical to the functioning of the environment. It highlights the importance of gathering further evidence before alternatives to conventional plastics are made available even more widely.”

The new study follows research published earlier in 2024 which highlighted that being exposed to the materials used in biodegradable teabags can result in earthworm populations experiencing up to 15% greater mortality, and have a detrimental effect on earthworm reproduction.

It has been published just a few weeks before the United Nations gathers world leaders meet in Busan, South Korea, for the final round of negotiations regarding a possible Global Plastics Treaty.

Professor Richard Thompson OBE FRS, senior author on the new study and Head of the University of Plymouth’s International Marine Litter Research Unit, will be at those discussions along with policy makers, scientists and other delegates from across the world.

He added: “It is clear that along with recycling and re-use, tackling plastic pollution will require a reduction in the quantities of plastics used and produced. There is increasing interest in alternative materials that could be used as substitutes for plastic, but this publication further emphasises the importance of testing new innovations in relevant environmental settings prior to widescale adoption. I firmly believe it is possible to tackle the plastic pollution crisis, but independent scientific evidence will be critical in helping us avoid unintended consequences as we look for solutions.”

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Journal

Environmental Science & Technology

DOI

10.1021/acs.est.4c05856 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Are bio-based microfibres less harmful than conventional plastic microfibres: Evidence from earthworms

Article Publication Date

5-Nov-2024

Microplastics increasing in freshwater, directly related to plastic production

 News Release 1-Nov-2024

Penn State

 

image: 

Jill Arriola, left, and Daniel Guarin collecting cores at the inlet to the John Heinz National Wildlife Refuge at Tinicum, which houses the largest remaining freshwater tidal marsh in Pennsylvania. 

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Credit: Lisa Emili/Penn State

UNIVERSITY PARK, Pa. — Microplastics have been steadily increasing in freshwater environments for decades and are directly tied to rising global plastic production since the 1950s, according to a new study by an interdisciplinary team of Penn State researchers. The findings provide insight into how microplastics move and spread in freshwater environments, which could be important for creating long-term solutions to reduce pollution, the researchers said. 

The work is available online now and will be published in the December issue of Science of the Total Environment.  

“Few studies examine how microplastics change over time,” said Nathaniel Warner, associate professor of civil and environmental engineering and the corresponding author on the paper. “Ours is one of the first to track microplastic levels in freshwater sediment from before the 1950s to today, showing that concentrations rise in line with plastic production.” 

Microplastics are tiny plastic particles that range in size from one micrometer, or 1/100 of the width of a human hair, to five millimeters, which is about the size of a pencil eraser. They can come from larger plastics that break down into smaller pieces or be made directly by manufacturers. For this study, the team examined freshwater sediment cores from four watersheds in Pennsylvania: Kiskiminetas River, Blacklick Creek, Raystown Lake and Darby Creek. 

Contrary to the team's expectations, the study found no correlation between population density or land use and high levels of microplastics.  

“Based on other findings in the literature, what we thought would be important turned out not to be driving forces in microplastic variation across sites, notably the percentage of microplastics related to developed area and population density,” said Lisa Emili, associate professor of physical geography and environmental studies at Penn State Altoona and a co-author on the paper. 

The researchers also said they were surprised to discover that while microplastic accumulation increased each decade through 2010, it decreased from 2010 to 2020.  

“Although this is a preliminary finding that requires further study, this decrease could be related to increased recycling efforts,” Emili said. 

According to the U.S. Environmental Protection Agency, recycling efforts for plastic increased significantly between 1980 and 2010. Although plastic production also increased, the percentage of recycled plastic increased from less than 0.3% in 1980 to nearly 8% in 2010. 

Additionally, Raymond Najjar, a professor of oceanography and a co-author on the paper, said that this study could shed light on the "missing plastics" paradox. This paradox challenges researchers' understanding of plastic waste in the ocean because, while estimates suggest that 7,000 to 25,000 kilotons of plastic enter the ocean each year, only about 250 kilotons are believed to be floating on the surface.  

“This suggests that estuaries, especially tidal marshes, may trap river-borne plastics before they reach the ocean,” said Najjar, who previously published in Frontiers in Marine Science on simulations of filter estuaries. “This could explain why there is far less plastic floating around in the surface ocean compared to how much is expected to be there given the input to the ocean from rivers.” 

Warner said these findings suggest that there will continue to be increasing amounts of microplastics in both water and sediment as people use more plastic.  

"Humans are ingesting plastic when they eat and drink and inhaling it when they breathe, and the long-term impacts are just beginning to be studied," Warner said. “However, we need to figure out how to release less plastic into the environment and how to reduce consumption and exposure.”

According to Emili, making a study like this one successful requires an interdisciplinary team. 

“This research shows Penn State’s broad expertise, bringing together a team from three campuses, five colleges and five disciplines,” Emili said. “We brought together complementary skillsets from our fields of chemistry, engineering, hydrology, oceanography and soil science.” 

This research project was initially funded with an Institute of Energy and the Environment seed grant. 

“That funded project really served as an ‘incubator’ for a continuation and expansion of our work exploring the fate and transport of microplastics in freshwater environments, with a particular focus on coastal locations,” Emili said. 

Najjar agreed and said he would like to get a more comprehensive assessment of the trapping of river-borne plastics in estuaries.  

“We have known for a long time that estuaries heavily process river borne materials, like carbon, sediment and nutrients, and this processing has a big impact on what eventually reaches the ocean,” Najjar said. “I think estuaries could be functioning in a similar way for plastics, but we need more than just a modeling study and a single core. We need to consider the likely sources and sinks of plastics for a given system, such as rivers, atmosphere, estuarine sediment and marshes.” 

Warner added that he hopes to examine how the composition and types of microplastics have changed over time and assess how the associated health risks have evolved. 

In addition to Emili, Najjar and Warner, the other Penn State researchers who contributed to the study include, Jutamas Bussarakum, lead author and doctoral student in the Department of Civil and Environmental Engineering; William Burgos, professor in the Department of Civil and Environmental Engineering; Samual Cohen, who graduated with their master’s degree in geography earlier this year; Kimberly Van Meter, assistant professor in the Department of Geography; Jon Sweetman, assistant research professor in the Department of Ecosystem Science and Management; Patrick Drohan, professor in the Department of Ecosystem Science and Management; Jill Arriola, assistant research professor in the Department of Meteorology and Atmospheric Science; and Katharina Pankratz, who graduated with their doctorate in civil and environmental engineering earlier this year. 

The U.S. National Science Foundation and the Penn State’s Commonwealth Campus Center Nodes (C3N) Program and the Institute of Energy and the Environment supported this research.

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Journal

Science of The Total Environment

DOI

10.1016/j.scitotenv.2024.176619 

Method of Research

Observational study

Subject of Research

Not applicable

Article Title

Decadal changes in microplastic accumulation in freshwater sediments: Evaluating influencing factors