Tag Archives: airborne microplastics

Plastics, Nanoplastics and Heart Attacks

A Landmark treaty on plastic pollution scheduled to be adopted by the end of 2024  must put scientific evidence front and center. In the run-up to the final negotiations, researchers have been publishing more reports, data sets and models about plastics than ever before….Researchers have also organized groups, such as the Scientists’ Coalition for an Effective Plastics Treaty


The treaty was originally conceived as a mechanism to end plastic pollution, which is sometimes taken to mean driving the amount of ‘mismanaged waste’ to zero by 2040. Mismanaged waste is plastic that isn’t recycled or disposed of in a well-managed landfill or incinerator, but rather ends up loose in the environment or burned in an open pit. Annual production of plastics has grown exponentially, from about 2 million tonnes in 1950 to 460 million tonnes in 2019 (current levels are on track to triple by 2060). Mismanaged waste is hard to measure–estimates put it at 74 million tonnes each year., expect to reach, by 2050, 122 million tonnes per year, under business-as-usual projections. Unless policies change, the peak of mismanaged plastic waste “is nowhere yet in sight”, he says.

A new report from environmental-policy researcher Nihan Karali and her colleagues at Lawrence Berkeley National Laboratory in California concludes that plastic production generated the equivalent of 2.24 gigatonnes of carbon dioxide in 2019, mainly from the energy-intensive process of extracting and refining the fossil fuels used to generate the petrochemicals that make up most virgin plastic.


An individual plastic typically contains hundreds of chemicals — many of which are toxic and can leach out — that make the material more flexible, water repellent, flame retardant or resistant to ultraviolet light. Last month, researchers released a report listing 16,000 chemicals associated with plastics, of which they found at least to be 4,200 hazardous… A study published in February 2024 of some 250 people undergoing surgery showed that nano- and microplastics in carotid-artery blockages were linked to increased risk of heart attacks, strokes and death.

Excerpt from Nicola Jones, Plastic pollution: three numbers that support a crackdown,  Nature, April 2024

What Do We Know about the Plastic Chemicals that Leach into Food?

Countries are currently negotiating a global plastics treaty to end plastic pollution. It is essential that the treaty addresses plastic chemicals because all plastics, from food packaging to car tires, contain thousands of chemicals that can leach into foodstuffs, homes, and the environment. Since many of these chemicals are hazardous, they can damage human health and the environment.

Plastic chemicals comprise all chemicals in plastics, including additives, processing aids, and impurities. A previous report by the United Nations Environment Program (UNEP) and other international institutions identified 13,000 plastic chemicals. The new PlastChem Report shows that there are more plastic chemicals than previously known, with over 16,000 chemicals included in the new PlastChem database that accompanies the report.
Further key findings of the report include:
• At least 4,200 plastic chemicals (or 26%) are of concern because of their high hazards to human health and the environment,
• More than 400 chemicals of concern can be present in each major plastic type, including in food packaging, and all tested plastics leached hazardous chemicals,

The report recommends : Increased transparency on the chemical composition of plastics is essential for closing data gaps, promoting a comprehensive management of plastic chemicals, and creating accountability across plastic value chains. A unified reporting, disclosure of the chemical composition of plastic materials and products as well as a “no data, no market” approach are recommended to ensure that essential
information about plastic chemicals becomes publicly available.

Excerpts from New Report Identifies Plastic Chemicals of Concern and Highlights
Approaches Towards Safer Plastics, Press Release of PlastChem, Mar. 14, 2024

The Curse of Nano-Plastics: Plastics in the Placenta

A flurry of recent studies has found that microplastics are present in virtually everything we consume, from bottled water to meat and plant-based food. Now, University of New Mexico Health Sciences researchers have used a new analytical tool to measure the microplastics present in human placentas. In a study published February 17 in the journal Toxicological Sciences, a team led by Matthew Campen, reported finding microplastics in all 62 of the placenta samples tested, with concentrations ranging from 6.5 to 790 micrograms per gram of tissue.

Although those numbers may seem small (a microgram is a millionth of a gram), Campen is worried about the health effects of a steadily rising volume of microplastics in the environment. For toxicologists, “dose makes the poison,” he said. “If the dose keeps going up, we start to worry. If we’re seeing effects on placentas, then all mammalian life on this planet could be impacted. That’s not good.”…The researchers found the most prevalent polymer in placental tissue was polyethylene, which is used to make plastic bags and bottles. It accounted for 54% of the total plastics. Polyvinyl chloride (better known as PVC) and nylon each represented about 10% of the total, with the remainder consisting of nine other polymers…

Plastic use worldwide has grown exponentially since the early 1950s, producing a metric ton of plastic waste for every person on the planet. About a third of the plastic that has been produced is still in use, but most of the rest has been discarded or sent to landfills, where it starts to break down from exposure to ultraviolet radiation present in sunlight. “That ends up in groundwater, and sometimes it aerosolizes and ends up in our environment,” Garcia said. “We’re not only getting it from ingestion but also through inhalation as well. It not only affects us as humans, but all off our animals – chickens, livestock – and all of our plants. We’re seeing it in everything.”…The concentration of microplastics in placentas is particularly troubling, he said, because the tissue has only been growing for eight months (it starts to form about a month into a pregnancy). “Other organs of your body are accumulating over much longer periods of time.”

Excepts from Michael Haederle,  Microplastics in Every Human Placenta, Feb. 20, 2024

Irradiating Plastics to Death: the IAEA Solution

Plastic pollution has become one of the major global environmental challenges of the century; projections show that by 2050 the oceans may have more plastic than fish. Nuclear technology has emerged as one innovative solution to this growing problem. The International Atomic Energy Agency (IAEA) has been working on an initiative called  Nuclear Technology for Controlling Plastic Pollution – NUTEC Plastics.

Nuclear technology can be used to innovate plastic waste recycling and support development of biodegradable, green alternatives to single use petroleum-based plastic products – an approach aimed at reducing the volume of plastic waste world-wide and prevent the plastics from reaching earth’s marine environments.  Nuclear techniques can also be used to quantify and characterize marine microplastic pollution and to assess their impact on coastal and marine ecosystems.  A global plastics monitoring network of marine laboratories can also help tackle marine pollution. Presently, there are 55 laboratories in the global NUTEC Plastics Monitoring Network. ..

The Philippines has a significant plastic pollution problem and a great interest in recycling. The Department of Science and Technology (DOST) in the Philippines has undertaken a pre-feasibility study for a pilot plant employing electron beam radiation to combine two waste streams – plastics and palm tree fibers – into a new consumer product, construction material…

The IAEA is unique within the United Nations system in having laboratories in Austria and Monaco that apply nuclear science to help states address some of the world’s biggest issues, including plastic pollution… The Monaco laboratories serve as the central hub to the global NUTEC Plastics Monitoring Network.

Excerpts from Sinead Harvey, More Plastic Than Fish by 2050 – IAEA Event Gathers Experts Working Together to Save Marine Environments from Plastic Pollution, IAEA Newsletter, Sept. 28, 2022
 

The Lies Around Plastics

California’s attorney general is investigating Exxon Mobil C and other fossil-fuel and petrochemical companies, accusing them of misleading the public about the impact of plastic pollution. He said his office has issued a subpoena to Exxon seeking information about what he called an “an aggressive campaign to deceive the public, perpetuating a myth that recycling can solve the plastics crisis.” 

“The truth is: The vast majority of plastic cannot be recycled,” Mr. Bonta said. “This first-of-its-kind investigation will examine the fossil fuel industry’s role in creating and exacerbating the plastics pollution crisis—and what laws, if any, have been broken in the process.”

Plastics and other petrochemical products are ubiquitous features of modern life, used to fashion everything from car fenders and shampoo bottles to smartphones. The United Nations estimates that the world generates more than 400 million metric tons of plastic waste every year and that vast amounts of that end up in oceans and other waterways. Plastics take hundreds of years to decompose and first break down into tiny particles. Scientists have found these particles in drinking water and food, and some estimate many human beings will consume dozens of pounds of plastic in their lifetimes.

Driven by the shale drilling revolution, which unleashed massive volumes of oil and gas, the petrochemical industry has invested more than $200 billion in U.S. plastics-and-chemical-manufacturing plants over the past decade. Exxon has invested billions of dollars on such facilities and is one of the world’s largest producers of virgin plastic.

Petrochemical companies have recently promised to invest billions of dollars in recycling. Exxon said last year that it would build its first large recycling facility in Texas, which it said would initially have the capacity to recycle 30,000 metric tons of plastic waste a year. The Minderoo Foundation, an Australian philanthropic group, estimates that Exxon produced 5.9 million metric tons of single-use plastic in 2019. The Environmental Protection Agency estimates the U.S. typically recycles only about 9% of produced plastic.

Excerpts from Christopher M. Matthew, Exxon Subpoenaed in California’s Probe of Plastics Makers, Apr. 29, 2022

See also Inside the long war to protect plastic

Ending the Plastic Paradise?

Heads of State, Ministers of environment and other representatives from 175 nations endorsed a historic resolution at the UN Environment Assembly (UNEA-5) on March 2, 2022: “End Plastic Pollution: Towards an internationally legally binding instrument.” The resolution addresses the full lifecycle of plastic, including its production, design and disposal. 

The resolution…establishes an Intergovernmental Negotiating Committee (INC), which will begin its work in 2022, with the ambition of completing a draft global legally binding agreement by the end of 2024…The UN Environment Programme (UNEP) will convene a forum by the end of 2022 that is open to all stakeholders in conjunction with the first session of the INC, to share knowledge and best practices in different parts of the world.

Plastic production soared from 2 million tonnes in 1950 to 348 million tonnes in 2017, becoming a global industry valued at US$522.6 billion, and it is expected to double in capacity by 2040. 

Exposure to plastics can harm human health, potentially affecting fertility, hormonal, metabolic and neurological activity, and open burning of plastics contributes to air pollution. By 2050 greenhouse gas emissions associated with plastic production, use and disposal would account for 15 per cent of allowed emissions, under the goal of limiting global warming to 1.5°C (34.7°F). More than 800 marine and coastal species are affected by this pollution through ingestion, entanglement, and other dangers.

Some 11 million tonnes of plastic waste flow annually into oceans. This may triple by 2040. A shift to a circular economy can reduce the volume of plastics entering oceans by over 80 per cent by 2040; reduce virgin plastic production by 55 per cent; save governments US$70 billion by 2040; reduce greenhouse gas emissions by 25 per cent; and create 700,000 additional jobs – mainly in the global south.

Excerpts from ,Historic day in the campaign to beat plastic pollution: Nations commit to develop a legally binding agreement, UNEP Press Release, Mar.  2, 202

Are We Transgressing the Planetary Boundaries?

There are an estimated 350,000 different types of manufactured chemicals on the global market. These include plastics, pesticides, industrial chemicals, chemicals in consumer products, antibiotics and other pharmaceuticals….The rate at which these pollutants are appearing in the environment far exceeds the capacity of governments to assess global and regional risks, let alone control any potential problems..

In 2009, an international team of researchers identified nine planetary boundaries that demarcate the remarkably stable state Earth has remained within for 10,000 years – since the dawn of civilization. These boundaries include greenhouse gas emissions, the ozone layer, forests, freshwater and biodiversity. The researchers quantified the boundaries that influence Earth’s stability, and concluded in 2015 that four boundaries have been breached. But the boundary for chemicals was one of two boundaries that remained unquantified.

This new research takes this a step further. The researchers say there are many ways that chemicals and plastics have negative effects on planetary health, from mining, fracking and drilling to extract raw materials to production and waste management.

Some of these pollutants can be found globally, from the Arctic to Antarctica, and can be extremely persistent…Global production and consumption of novel entities is set to continue to grow. The total mass of plastics on the planet is now over twice the mass of all living mammals, and roughly 80% of all plastics ever produced remain in the environment. Plastics contain over 10,000 other chemicals, so their environmental degradation creates new combinations of materials – and unprecedented environmental hazards. Production of plastics is set to increase and predictions indicate that the release of plastic pollution to the environment will rise too, despite huge efforts in many countries to reduce waste.

Excerpt from Safe planetary boundary for pollutants, including plastics, exceeded, say researchers, Stockholm Resilience Center Press Release, Jan. 18, 2022

For an alternative view on planetary boundaries see NY Times Article, 2015

Global Microbiome Living on Plastics

The number of microbial enzymes with the ability to degrade plastic is growing, in correlation with local levels of plastic pollution. That is the finding of a study from Chalmers University of Technology, Sweden, that measured samples of environmental DNA from around the globe. The results illustrate the impact plastic pollution is having on the environment, and hint at potential new solutions for managing the problem.

The study analyzed samples of environmental DNA from hundreds of locations around the world. The researchers used computer modelling to search for microbial enzymes with plastic-degrading potential, which was then cross-referenced with the official numbers for plastic waste pollution across countries and oceans. “Using our models, we found multiple lines of evidence supporting the fact that the global microbiome’s plastic-degrading potential correlates strongly with measurements of environmental plastic pollution – a significant demonstration of how the environment is responding to the pressures we are placing on it,” says Aleksej Zelezniak, Associate Professor in Systems Biology at Chalmers University of Technology. 

More enzymes in the most polluted areas: In other words, the quantity and diversity of plastic-degrading enzymes is increasing, in direct response to local levels of plastic pollution. In total, over 30,000 enzyme ‘homologues’ were found with the potential to degrade 10 different types of commonly used plastic. Homologues are members of protein sequences sharing similar properties. Some of the locations that contained the highest amounts were notoriously highly polluted areas, for example samples from the Mediterranean Sea and South Pacific Ocean…

The researchers believe that their results could potentially be used to discover and adapt enzymes for novel recycling processes…“The next step would be to test the most promising enzyme candidates in the lab to closely investigate their properties and the rate of plastic degradation they can achieve. From there you could engineer microbial communities with targeted degrading functions for specific polymer types,” explains Aleksej Zelezniak.

Plastic-degrading enzymes increasing in correlation with pollution, Chalmers University of Technology Press Release, Dec. 14, 2021

When the Cat’s Away the Mice Pollute

Police don’t share schedules of planned raids. Yet America’s Environmental Protection Agency (EPA) does not seem convinced of the value of surprise in deterring bad behavior. Every year it publishes a list of dates, spaced at six-day intervals, on which it will require state and local agencies to provide data on concentrations of harmful fine particulate matter (pm2.5), such as soot or cement dust…

A new paper by Eric Zou of the University of Oregon makes use of satellite images to spy on polluters at times when they think no one is watching. NASA, America’s space agency, publishes data on the concentration of aerosol particles—ranging from natural dust to man-made toxins—all around the world, as seen from space. For every day in 2001-13, Mr Zou compiled these readings in the vicinity of each of America’s 1,200 air-monitoring sites.

Although some stations provided data continuously, 30-50% of them sent reports only once every six days. For these sites, Mr Zou studied how aerosol levels varied based on whether data would be reported. Sure enough, the air was consistently cleaner in these areas on monitoring days than it was the rest of the time, by a margin of 1.6%. Reporting schedules were almost certainly the cause….The size of this “pollution gap” differed by region. It was biggest in parts of Appalachia and the Midwest with lots of mining, and in the northern Mountain West, where paper and lumber mills are common.

The magnitude of the gap also depended on the cost of being caught. Every year, the EPA produces a list of counties whose average air quality falls below minimum standards. The punishments for inclusion are costly: factories become subject to burdensome clean-technology requirements, and local governments can be fined. When firms risked facing sanctions, they seemed to game the system more aggressively. In counties that exceeded the pm2.5 limit in a given month, the pollution gap in the following month swelled to 7%. In all other cases, it was just 1.2%….

Excerpts from Poorly devised regulation lets firms pollute with abandon: We Were Expecting you, Economist, Sept. 4, 2021

Yummy Plastics

“From Waste to Food: A Generator of Future Food” by Ting Lu and Stephen Techtmann, won the Merck 1 million prize.  It concerns an efficient, economical and versatile technology that converts wastes such as end-of-life plastics into edible foods. These foods contain all the required nutrition, are non-toxic, provide health benefits, and additionally allow for personalization needs. This technology promises to transform waste streams into nutritious food supplements, thus solving the two problems of increasing food scarcity and plastic waste simultaneously.

The core of the proposed technology is to harness synthetic microbial consortia – a combination of natural and rationally engineered microorganisms – in order to efficiently convert waste into food. The project will comprise four research goals: conversion from polyethylene terephthalate (PET) to protein powder (goal 1), augmentation of biosafety for food and for the environment (goal 2), introduction of nutritional and health-promoting contents (goal 3), and expansion of the technology to include additional plastics or other types of waste (goal 4). The proposed work will establish a transformative basis for food generation.

  • Excerpts from Future Insight Prize, Merck Press Release, July 13, 2021

Junk: the Engine of Green Growth

“Plastic waste is not just a global crisis that threatens economic recovery, climate, and nature. It is also an investment opportunity that can flip it from a scourge into an engine for economic development,” said Rob Kaplan, who founded Circulate Capital in 2017. Initially the firm sought to back companies in India and Southeast Asia, such as recycling or waste-sorting companies, that help reduce the amount of plastic waste that winds up in the ocean.

In 2019 it raised a $106 million debt and project finance fund, Circulate Capital Ocean Fund, backed by a handful of large multinational corporations that include Coca-Cola, Danone,  Procter & Gamble,  and Unilever…Circulate is one of a small but growing number of firms investing in companies that contribute to what they call the circular economy, a business model that seeks to eliminate waste that organizations produce, continuously reuse products and materials and regenerate natural systems.

An estimated 30 private-market funds, including private-equity, venture and debt strategies focused on the circular economy in the first half of 2020, up from just three in 2016….A number of large multinational corporations are funding these firms’ efforts as part of a broader push to reduce both the overall waste their own companies produce and the amount of virgin materials they use.

Unilever, which has backed funds managed by Circulate and New York-based Closed Loop Partners, aims to cut in half the amount of virgin plastic it uses by 2025 and plans to collect and process more plastic packaging than it sells. Coca-Cola, also a backer of Circulate’s Ocean fund, aims to make all of its global packaging recyclable by 2025 and to use at least 50% of recycled packaging material by 2030, among other goals.

Excerpt from Laura Kreutzer, Growth Firms See Plastic Waste as an Investment Opportunity, WSJ, June 23, 2021
 

Save Time and Money but Destroy Soil and Oceans

The images of swaths of garbage floating on the oceans’ surface have become a rallying call to address plastic pollution, but there is more to this challenge than meets the eye. While plastics and microplastics – items smaller than 5 mm – accumulate and impact marine environments, much of the problem is rooted in land contamination. Land-based plastic pollution, which often feeds into the oceans, is estimated to be at least four times higher than what is in the oceans, according to a study published in Global Change Biology. 

“Soil is the main source of microplastics reaching oceans through soil erosion and surface runoff,”  Plastics settle in soil through disposal in landfills, as well as through the use of plastic-sheets in agriculture or application of microplastic contaminated compost. “Direct disposal of plastics to ocean is relatively less pronounced compared to the transfer of microplastics from land. Microplastics, lighter than soil particles, such as sand, silt and clay, are easily lost to waterways,”…

“We contribute to plastic pollution through indiscriminate disposal of plastics in landfills and use of microbeads in cosmetics and microfibers in textiles. There are efforts to produce biodegradable plastics, which may provide some solution to plastic pollution, but bioplastic may not be the silver bullet to manage plastic pollution.” Commonly used biodegradable bioplastics “retain their mechanical integrity under natural conditions, potentially causing physical harm if they are ingested by marine or terrestrial animals.” “The fate of biodegradable bioplastics in natural and engineered environments could be potentially problematic. Methane is a product of biodegradation in anaerobic environments in landfills.” These bioplastics, furthermore, require high temperatures, controlled aeration and humidity to degrade completely.

Due to their small size, microplastics, especially nanoplastics resulting from the degradation of microplastic, can enter organisms’ internal organs, where they could potentially transfer contaminants attached to them. These can include persistent organic pollutants, like polychlorinated biphenyls (PCBs), as well as trace metals like mercury and lead. The plastics and pollutants that accumulate on or in them enter the food chain and can eventually be transferred to humans, causing growing food safety concerns.

The Joint FAO/IAEA Centre’s laboratories are equipped to research the presence of microplastics in food. “Techniques such as energy dispersive X-ray spectroscopy and infrared and Raman spectroscopy can be applied to screen for plastics in foods, enabling risk assessment and management,” said Andrew Cannavan, Head of the Joint Centre’s Food and Environmental Protection Section. 

Excerpt from Joanne Liou Out of Sight but not out of Mind: IAEA and FAO Launch R&D to Identify Sources, Impacts of Microplastic Pollution in Soil, IAEA Press Release, July 2, 2021

The Plastics Revolution: A Century Later

Businesses pay a fee to Tontoton,  a company established in 2019,  for every ton of plastic that they generate. Tontoton then uses the money to employ scavengers, who retrieve an equal weight of plastic garbage in Vietnam — the world’s No. 4 source of ocean debris…Tontoton said it has the only such program in Vietnam, while Plastic Bank runs a similar one in Indonesia and the Philippines, and the Plastic Collective covers Malaysia, Thailand, and Cambodia…Tontoton targets the worst ocean-bound rubbish, called orphan plastic because it cannot be recycled. Trash pickers find the single-use plastic along the cyan waters hugging Vietnam’s Phu Quoc and Hon Son islands. Their goal is to collect 5,000 tons a year and send it to INSEE, part of Siam City Cement, to be burned for energy….

These cleanup programs have sprung up globally as doubts emerge about recycling, which used to seem like a win-win idea because consumers could keep consuming and the environment could stay pristine. But instead, for decades, the public believed its plastic was being recycled, only to find that 91% of it was not, according to a study in the peer-reviewed journal Science Advances, assessing all plastic from 1950-2015.

Vietnam is a focus of cleanup campaigns because it’s among the top five countries sending litter to sea, along with China, Indonesia, the Philippines, and Thailand…These Asian countries earned this marker because they import so much waste for processing from the rest of the world.

Tontoton says clients sign a letter committing to multiple strategies beyond offsets, including plastic substitutes and reduction. The company helps them offset or “neutralize” plastic already used, but this isn’t a “getaway car” to escape broader responsibility. “Plastic neutralization cannot solve the problem by itself.”

Excerpt from LIEN HOANG, Vietnam tests waters for plastic credits to fight marine pollution, April 15, 2021

How the Global Trade in Plastics Spills Over the Oceans

Low-value or “residual” plastics – those left over after more valuable plastic is recovered for recycling – are most likely to end up as pollution. So how does this happen? In Southeast Asia, often only registered recyclers are allowed to import plastic waste. But due to high volumes, registered recyclers typically on-sell plastic bales to informal processors…When plastic types were considered low value, informal processors frequently dumped them at uncontrolled landfills or into waterways.

Plastics stockpiled outdoors can be blown into the environment, including the ocean. Burning the plastic releases toxic smoke, causing harm to human health and the environment. When informal processing facilities wash plastics, small pieces end up in wastewater, which is discharged directly into waterways, and ultimately, the ocean.

The price of many recycled plastics has crashed in recent years due to oversupply, import restrictions and falling oil prices, (amplified by the COVID-19 pandemic). However clean bales of (polyethylene terephthalate) PET and (high-density polyethylene) HDPE are still in demand. In Australia, material recovery facilities currently sort PET and HDPE into separate bales. But small contaminants of other materials (such as caps and plastic labels) remain, making it harder to recycle into high quality new products. Before the price of many recycled plastics dropped, Australia baled and traded all other resin types together as “mixed plastics”. But the price for mixed plastics has fallen to zero and they’re now largely stockpiled or landfilled in Australia.

Excerpts from Monique Retamal et al., Why Your Recycled Plastic May End up in the Ocean, the Maritime Executive, Mar. 8, 2021

Air Pollution: the Microplastics We Breath

 Scientists measured microplastics — tiny particles and fibers of plastic that can float in the air like dust — and found that over 1,000 tons a year are falling into wilderness areas and national parks in the western U.S.  Janice Brahney of Utah State University and her team identified samples of microplastics and other particulates collected over 14 months in 11 national parks and wilderness areas to create the study published in the journal Science, on June 12, 2020.  Pieces of plastic less than 5 mm in length, or microplastics, occur in the environment as a consequence of plastic pollution…

The presence of microplastics in oceans and water supplies has been a matter of concern for some time, but the impact of airborne microplastics is a relatively new area of study. Though microplastics are found nearly everywhere on Earth, the sources and processes behind their ubiquitous distribution, or the “global plastic cycle,” remain vaguely understood.  Initially overlooked, recent studies have suggested that long-range atmospheric transport plays an important role in carrying microplastic pollution vast distances and to remote locations

Examination of weekly wet and monthly dry samples from 11 sites allowed the authors to estimate that more than 1,000 tons of microplastics are deposited onto protected lands in the western U.S. each year, equivalent to more than 123 million plastic water bottles.

The ubiquity of microplastics in the atmosphere has unknown consequences for humans and animals, but the research team observed sizes of particles that were within the ranges that accumulate in lung tissue. Moreover, the accumulation of plastic in the wilderness areas and national parks could well influence the ecosystems in complicated ways.

Excerpts, VICTORIA PRIESKOP, Scientists Find Tons of Microplastics Polluting National Parks, Courthouse News Service, June 11, 2020