Consequences of using plastics

[kassy]

Interesting. Thanks!

Each rotifer, named from the Latin for “wheel-bearer” owing to the whirling wheel of cilia around their mouths, can create between 348,000 and 366,000 nanoplastics – particles smaller than one micrometre – each day.

The animals are microscopic, ubiquitous and abundant, with up to 23,000 individuals found living in one litre of water, in one location. The researchers, from a team led by the University of Massachusetts Amherst, calculated that in Poyang Lake, the largest lake in China, rotifers were creating 13.3 quadrillion of these plastic particles every day.

...

The scientists sought to examine what role aquatic life might play in microplastic creation, especially after the discovery in 2018 that Antarctic krill are able to break down polyethylene balls into fragments of less than one micrometre.

You have to wonder what this does with the organisms. It´s probably less nutricious then the algae they are looking for.

[kassy]

Scientists found hundreds of toxic chemicals in recycled plastics

When scientists examined pellets from recycled plastic collected in 13 countries they found hundreds of toxic chemicals, including pesticides and pharmaceuticals. Because of this, the scientists judge recycled plastics unfit for most purposes and a hinder in the attempts to create a circular economy.

...

"Plastic recycling has been touted as a solution to the plastics pollution crisis, but toxic chemicals in plastics complicate their reuse and disposal and hinder recycling," says Professor Bethanie Carney Almroth, of the University of Gothenburg.

Over 600 chemical compounds identified

In a recently published study in Data in Brief via ScienceDirect, led by Carney Almroth, plastic pellets from plastic recycle plants in 13 different countriesin Africa, South America, Asia and Eastern Europe were found to contain hundreds of chemicals, including numerous highly toxic pesticides.

In total, 491 organic compounds were detected and quantified in the pellets, with an additional 170 compounds tentatively annotated. These compounds span various classes, including pesticides, pharmaceuticals, industrial chemicals, plastic additives.

...

"Need to phase out harmful chemicals"

Professor Bethanie Carney Almroth brings a clear message to next week's meeting in Nairobi:

"Numerous studies show that hazardous chemicals can accumulate even in relatively close-loop plastic recycling systems. We need to rapidly phase-out plastic chemicals that can cause harm to human health and the environment."

https://www.sciencedaily.com/releases/2023/11/231110112511.htm

[kassy]

This is great but maybe we should just stop (or reduce very much unless absolutely necessary) using plastics...

(at least 80% of plastic use could be stopped in a few years using more natural replacements like wood, glass, paper, etc which do not create micro and nanoplastics in nature)

We should but all these changes have their challenges.

If we change plastic bottles to glass we would need to make a lot more glass which is energy expensive. Since it weighs more it would cost more to transport.

Wood and paper. We don´t really have enough of them? Probably depends on the substitutions made but growing production forests takes some time.

A strong reduction in wasteful use is probably our best bet although we do this by tiny steps.

One source of microplastics is fast fashion. By prewashing them in a facility with filters you can catch them but this is still not required. If we had a EU law that prescribed the treatment we could fix it. Wash at the production centres or wash here after import.

Oh and all fast fashion should be sold or recycled in the EU. Can´t keep dumping it in the Atamaca.

We are making some progress in getting rid of the more wasteful single use items but the laws are too specific. Targeting some items instead of the overall problem. So we have things like half see trough bags which are plastic and paper.

We also have a law aimed at reducing plastic packaging so at the market they unwrap the plastic from the cheese pieces, throw it away and then wrap it in paper.

[El Cid]

....

1. If we change plastic bottles to glass we would need to make a lot more glass which is energy expensive. Since it weighs more it would cost more to transport.

2. Wood and paper. We don´t really have enough of them? Probably depends on the substitutions made but growing production forests takes some time.

3. Oh and all fast fashion should be sold or recycled in the EU. Can´t keep dumping it in the Atamaca.

some comments on the above (I inserted the numbers, becaus it is easier to answer that way):

1: glass can be reused many many times without breaking into pieces and recasting it  - the way we mostly do it now. If you standardized glass sizes, eg. 0,25 l 0,5 l 1 l then you can wash and sterilize and refill them. This worked in my country during socialism. There will be no special glass type for Coca Cola or wine, etc. There will be a few different sizes with the same shape

2: Paper is renewable. We can cut as many trees as we like, so long as we replant them or if we keep pollarding/coppicing forests (as it was often done in the middle ages)they will regrow for hundreds of years.

3: Recycling plastic containing clothes is a very bad idea as during every time you wash them gazillions of microplastics are shed. Plastic containg clothing should be banned.

Plastic is only used because it "seems" cheap, because the extrenalies are not paid for. The products we buy are cheap because we don't pay for the bad things they cause

If we switch to more sustainable alternatives the price of those alternatives will obviously go up which will reduce demand. If we want a sustainable economy then the price of many things will go up by a lot. We will literally have to pay the price

[kassy]

Rise of microplastics discovered in placentas of Hawaii mothers

A new study by researchers at the John A. Burns School of Medicine (JABSOM) at the University of Hawaiʻi at Mānoa and Kapiʻolani Medical Center for Women & Children examined placentas donated by women who delivered in Hawaiʻi from 2006 to 2021, and found the presence of microplastic particles in the placenta.

...

The researchers collected and studied 10 placentas in 2006, 2013 and 2021 and found the presence of microplastics grew each year.

In 2006, 6 of the 10 placentas contained microplastics.
In 2013, microplastics were found in 9 of the 10 placentas.
In 2021, researchers found microplastics in all 10 placentas.
"We believe that the plastics may be floating around in food or being inhaled. It's coming through our digestive fluids or lungs, and the particles are getting absorbed through the gut and traveling through the bloodstream, and then somehow collecting in the placenta during pregnancy," Lee said.

...

https://www.sciencedaily.com/releases/2023/11/231129234437.htm

[kassy]

Durable plastic pollution easily, cleanly degrades with new catalyst

Found in fishing nets, carpet, clothing, Nylon-6 is a major contributor to plastic pollution, including ocean pollution. Now, chemists have developed a new catalyst that quickly, cleanly and completely breaks down Nylon-6 in a matter of minutes -- without generating harmful byproducts. Even better: The process does not require toxic solvents, expensive materials or extreme conditions, making it practical for everyday applications. In experiments, the new process recovered 99% of the polymer's building blocks, which can then be upcycled into higher-value products.

details:
https://www.sciencedaily.com/releases/2023/11/231130113054.htm

[morganism]

Hurricane Larry dumped 100,000 microplastics per sq. meter on Newfoundland each day
It's another sign of how plasticized our environment has become.

As Hurricane Larry curved north in the Atlantic in 2021, sparing the eastern seaboard of the United States, a special instrument was waiting for it on the coast of Newfoundland. Because hurricanes feed on warm ocean water, scientists wondered whether such a storm could pick up microplastics from the sea surface and deposit them when it made landfall. Larry was literally a perfect storm: Because it hadn’t touched land before reaching the island, anything it dropped would have been scavenged from the water or air, as opposed to, say, a highly populated city, where you’d expect to find lots of microplastics.

As Larry passed over Newfoundland, the instrument gobbled up what fell from the sky. That included rain, of course, but also gobs of microplastics, defined as bits smaller than 5 millimeters, or about the width of a pencil eraser. At its peak, Larry was depositing over 100,000 microplastics per square meter of land per day, the researchers found in a recent paper published in the journal Communications Earth and Environment. Add hurricanes, then, to the growing list of ways that tiny plastic particles are not only infiltrating every corner of the environment, but readily moving between land, sea, and air.

https://arstechnica.com/science/2023/12/hurricane-larry-dumped-100000-microplastics-per-sq-meter-on-newfoundland-each-day/#p3

[neal]

microplastics in a hurricane....

....As [Hurricane] Larry passed over Newfoundland, the instrument gobbled up what fell from the sky. That included rain, of course, but also gobs of microplastics, defined as bits smaller than 5 millimeters, or about the width of a pencil eraser. At its peak, Larry was depositing over 100,000 microplastics per square meter of land per day, the researchers found in a recent paper published in the journal Communications Earth and Environment. Add hurricanes, then, to the growing list of ways that tiny plastic particles are not only infiltrating every corner of the environment, but readily moving between land, sea, and air....

..So microplastics don’t just flush into the sea and stay there—they blow into the atmosphere and back onto land, only to get picked back up again by winds and blown out to sea. Back and forth, back and forth. “It’s becoming quite clear that the ocean-to-atmosphere exchange is a very real thing,” says Allen. “And the numbers in this paper here are just staggering. It’s arriving in Newfoundland at just the time of year when all the biota—in the ponds and things—are all just trying to fatten up and breed for winter.”...

https://www.wired.com/story/oh-good-hurricanes-are-now-made-of-microplastics/

[kiwichick16]

el cid ....@ reply 203 .......+1

[neal]

Think about your bottled water (or not)--240,000 (+/-)particles per liter

Abstract
Plastics are now omnipresent in our daily lives. The existence of microplastics (1 µm to 5 mm in length) and possibly even nanoplastics (<1 μm) has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body. However, detecting nanoplastics imposes tremendous analytical challenges on both the nano-level sensitivity and the plastic-identifying specificity, leading to a knowledge gap in this mysterious nanoworld surrounding us. To address these challenges, we developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm that allows micro-nano plastic analysis at the single-particle level with high chemical specificity and throughput. We first validated the sensitivity enhancement of the narrow band of SRS to enable high-speed single nanoplastic detection below 100 nm. We then devised a data-driven spectral matching algorithm to address spectral identification challenges imposed by sensitive narrow-band hyperspectral imaging and achieve robust determination of common plastic polymers. With the established technique, we studied the micro-nano plastics from bottled water as a model system. We successfully detected and identified nanoplastics from major plastic types. Micro-nano plastics concentrations were estimated to be about 2.4 ± 1.3 × 105 particles per liter of bottled water, about 90% of which are nanoplastics. This is orders of magnitude more than the microplastic abundance reported previously in bottled water. High-throughput single-particle counting revealed extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies; the resulting multidimensional profiling sheds light on the science of nanoplastics.
https://www.pnas.org/doi/full/10.1073/pnas.2300582121

[kassy]

Moved post above from persistent chemical pollution thread.

Also:

Majority of burgers, steaks, chicken and plant-based meats contain microplastics, study reveals

The vast majority of meat and plant-based proteins contain tiny plastic particles, a new study has found.

While the prolific presence of microplastics in fish and shellfish has long been known, there has been less exploration into how proteins like beef and chicken are impacted by the world’s burgeoning plastic pollution.

Micro- and nanoplastics are miniscule particles which shed from larger plastic products. Increasing numbers of studies have shown that they can damage cells in the human body, leading to serious health effects, including cancers, lung disease, and birth defects.

The latest study discovered that 90 per cent of proteins - including pork, beef, chicken, tofu, and three different plant-based alternatives - contain as much plastic as fish.

Highly-processed foods like fish sticks, chicken nuggets, tofu, and plant-based burgers were found to contain more microplastics per gram than minimally-processed proteins like chicken breast but the difference was statistically negligible.

...

https://www.independent.co.uk/climate-change/news/plastic-pollution-food-fish-meat-b2476113.html

We have a meal!

[neal]

uptake in plants of nano-plastics with deterioration of nutritional properties


Abstract
Nanoplastics are emerging pollutants of global concern. Agricultural soil is becoming a primary sink for nanoplastics generated from plastic debris. The uptake and accumulation of nanoplastics by crops contaminate the food chain and pose unexpected risks to human health. However, whether nanoplastics can enter grains and their impact on the grains of crop grown in contaminated soil is still unknown. Here, the translocation of polystyrene nanoplastics (PS-NPs) in crops, including peanut (Arachis hypogaea L.) and rice (Oryza sativa L.) is investigated. It is demonstrated PS-NPs translocation from the root and accumulation in the grains at the maturation stage. The treatment with PS-NPs (250 mg kg−1) increases the empty-shell numbers of rice grain by 35.45%, thereby decreasing the seed-setting rate of rice by 3.02%, and also decreases the average seed weight of peanuts by 3.45%. Moreover, PS-NPs exerted adverse effects on nutritional quality, such as decreasing the content of mineral elements, amino acids, and unsaturated fatty acids. To the knowledge, this is the first report of the presence of nanoplastics in the grains of crop plants grown in soil containing nanoplastics, and the results highlight the impact of nanoplastics on the yield and nutritional quality of crop grains.

https://onlinelibrary.wiley.com/doi/full/10.1002/advs.202202336

[neal]

what goes in, comes out, and is distributed via our treatment systems

Abstract
This literature review addresses the presence of plastic in domestic wastewater, an increasingly important facet of the widespread use of plastic and its detrimental effects on the environment, with a focus on microplastics (MPs) in sewage sludge and their implications for a circular economy. Extensive research has been conducted on the occurrence of MPs in wastewater treatment plants. Sewage sludge is a byproduct of such plants that are widely used in the agricultural and other sectors but may contain emerging contaminants, including MPs, that can pose a significant risk to the environment. The review highlights the high concentrations of MPs in sewage sludge and underscores the need for appropriate disposal methods to prevent soil contamination. MPs can also detrimentally interact with other emerging contaminants, such as heavy metals and organophosphate esters. While extraction technologies exist to remove MPs from wastewater, their implementation is subject to technical and economic considerations. Future research should focus on the optimization and efficacy of these technologies to ensure safe sludge management. Given the high levels of MPs and other emerging contaminants found in sewage sludge, it is crucial to implement technologies that enable sustainable sludge disposal. By acknowledging these challenges and developing appropriate solutions, we can mitigate the environmental impacts of plastic and promote sustainable waste management practices.

https://www.sciencedirect.com/science/article/pii/S2352186423001724

[kassy]

U.S. health costs related to chemicals in plastics reached $250 billion in 2018

Endocrine-disrupting chemicals (EDCs) in plastics pose a serious threat to public health and cost the U.S. an estimated $250 billion in increased health care costs in 2018, according to new research published in the Journal of the Endocrine Society.

Plastics contain many hazardous, endocrine-disrupting chemicals that leach and contaminate humans and the environment.

These chemicals disturb the body's hormone systems and can cause cancer, diabetes, reproductive disorders, neurological impairments of developing fetuses and children, and death.

Potential options under discussion as part of a Global Plastics Treaty include interventions to reduce EDC exposure to protect public health and the environment, and data on the health costs of EDCs could help move this initiative forward.

"Our study found plastics contribute substantially to disease and associated social costs in the U.S., about $250 billion in 2018 alone. These costs are equivalent to 1.22% of the Gross Domestic Product. The diseases due to plastics run the entire life course from preterm birth to obesity, heart disease and cancers," said study author Leonardo Trasande, M.D., M.P.P., of NYU Grossman School of Medicine and NYU Wagner Graduate School of Public Service in New York, N.Y. Trasande has represented the Society at intergovernmental meetings to address plastic pollution and its health effects.

"Our study drives home the need to address chemicals used in plastic materials as part of the Global Plastics Treaty," Trasande said.

...

https://www.sciencedaily.com/releases/2024/01/240111113117.htm

[morganism]

Microplastics in every human placenta, new UNM Health Sciences research discovers

In a study published February 17 in the journal Toxicological Sciences, a team led by Matthew Campen, PhD, Regents’ Professor in the UNM Department of Pharmaceutical Sciences, 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 plant could be impacted. That’s not good.”

In the study, Campen and his team, partnering with colleagues at the Baylor College of Medicine and Oklahoma State University, analyzed donated placenta tissue. In a process called saponification, they chemically treated the samples to “digest” the fat and proteins into a kind of soap.

Then, they spun each sample in an ultracentrifuge, which left a small nugget of plastic at the bottom of a tube. Next, using a technique called pyrolysis, they put the plastic pellet in a metal cup and heated it to 600 degrees Celsius, then captured gas emissions as different types of plastic combusted at specific temperatures.

“The gas emission goes into a mass spectrometer and gives you a specific fingerprint,” Campen said. “It’s really cool.”

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.

Marcus Garcia, PharmD, a postdoctoral fellow in Campen’s lab who performed many of the experiments, said that until now, it has been difficult to quantify how much microplastic was present in human tissue. Typically, researchers would simply count the number of particles visible under a microscope, even though some particles are too small to be seen.

With the new analytical method, he said, “We can take it to that next step to be able to adequately quantify it and say, ‘This is how many micrograms or milligrams,’ depending on the plastics that we have.”

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.”

Campen points out that many plastics have a long half-life – the amount of time needed for half of a sample to degrade. “So, the half-life of some things is 300 years and the half-life of others is 50 years, but between now and 300 years some of that plastic gets degraded,” he said. “Those microplastics that we’re seeing in the environment are probably 40 or 50 years old.”

While microplastics are already present in our bodies, it is unclear what health effects they might have, if any. Traditionally, plastics have been assumed to be biologically inert, but some microplastics so small they are measured in nanometers – a billionth of a meter – and are capable of crossing cell membranes, he said.

Campen said the growing concentration of microplastics in human tissue might explain puzzling increases in some types of health problems, such as inflammatory bowel disease and colon cancer in people under 50, as well as declining sperm counts.

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.”

Campen and his colleagues are planning further research to answer some of these questions, but in the meantime he is deeply concerned by the growing production of plastics worldwide.

“It’s only getting worse, and the trajectory is it will double every 10 to 15 years,” he said. “So, even if we were to stop it today, in 2050 there will be three times as much plastic in the background as there is now. And we’re not going to stop it today.”
Journal

Toxicological Sciences
DOI

10.1093/toxsci/kfae021

https://www.eurekalert.org/news-releases/1034977

[neal]

Microplastics in arterial plaque leads to worse outcomes  (a paywalled site), so this image instead

[morganism]

Science Alert wrote up the plaque story too

Plastic Found Inside More Than 50% of Plaques From Clogged Arteries

https://www.sciencealert.com/plastic-found-inside-more-than-50-of-plaques-from-clogged-arteries

[kassy]

researchers found nearly 60 percent of them had measurable amounts of polyethylene in plaques pulled from their fat-thickened arteries, and 12 percent also had polyvinyl chloride (PVC) in extracted fat deposits.

PVC comes in both rigid and flexible forms, and is used to make water pipes, plastic bottles, flooring, and packaging. Polyethylene is the most commonly produced plastic, used for plastic bags, films, and bottles, too.

I wonder if someone has a historical record of clogged artery stuff so they can check historical patterns...

[morganism]

US appeals court kills ban on plastic containers contaminated with PFAS

Conservative fifth circuit overturns EPA’s ban prohibiting Inhance from using manufacturing process creating toxic compound

A federal appeals court in the US has killed a ban on plastic containers contaminated with highly toxic PFAS “forever chemicals” found to leach at alarming levels into food, cosmetics, household cleaners, pesticides and other products across the economy.

Houston-based Inhance manufactures an estimated 200m containers annually with a process that creates, among other chemicals, PFOA, a toxic PFAS compound. The Environmental Protection Agency (EPA) in December prohibited Inhance from using the manufacturing process.

But the conservative fifth circuit court of appeals court overturned the ban. The judges did not deny the containers’ health risks, but said the EPA could not regulate the buckets under the statute it used.

The rule requires companies to alert the EPA if a new industrial process creates hazardous chemicals. Inhance has produced the containers for decades and argued that its process is not new, so it is not subject to the regulations. The EPA argued that it only became aware that Inhance’s process created PFOA in 2020, so it could be regulated as a new use, but the court disagreed.

“The court did not dispute EPA’s underlying decision that this is a danger to human health, what they did was say it’s not a new use, which I think is wrong … but this case isn’t over by any stretch,” said Kyla Bennett, a former EPA official now with the Public Employees for Environmental Responsibility (Peer) non-profit, which has intervened in legal proceedings.
(more background)

https://www.theguardian.com/us-news/2024/mar/30/pfas-ban-plastic-containers-court

[kassy]

Plastic pollution can kill variety of ocean embryos

High levels of plastic pollution can kill the embryos of a wide range of ocean animals, new research shows.

Scientists tested the effects of new PVC pellets (pre-production "nurdles" used to make many plastic products) on the development of seven species, spanning all major groups (superphyla) of ocean animals.

Exposure to high concentrations of PVC pellets prevented healthy development in all seven species.

The main process affected was morphogenesis -- an organism developing its shape -- and shapeless embryos cannot survive.

The study, by an international team led by the Stazione Zoologica Anton Dohrn (Italy) and the University of Exeter (UK), highlights the "potentially catastrophic effects" of rising levels of plastic in the ocean.

"When exposed to high levels of new PVC pellets, the species we examined went wrong in different ways," said first author Dr Eva Jimenez-Guri.

"Some failed to make a shell or a notocord, some failed to form proper bilateral (left-right) features, some just stopped developing after a few rounds of cell division.

"They all failed to make a viable embryo."

The study also included three species that reproduce asexually by regeneration (splitting) and found these were also affected by high concentrations of new PVC pellets.

"The level of pollution we examined would only be seen in circumstances such as a spill of PVC pellets," Dr Jimenez-Guri said.

"We know these happen. For example, millions of pellets were spilled from a cargo ship off Portugal in January.

"Rivers and beaches near petrochemical plants have also been found to contain very high levels of pre-production pellets."

The European Union is currently debating legislation aimed to reduce releases of pre-production plastic pellets.

The study also examined the toxic effects of plastic samples recovered from beaches.

While the effects were not as widespread as those of new PVC pellets, high concentrations were found to affect the development of molluscs, sea urchins, sea stars and sea squirts.

Coasts and rivers are known hotspots for plastic pollution and -- as the species in the study all live in coastal areas -- severe pollution could have a major impact.

"If you have extreme pollution at a time when these species are reproducing, then you don't have the next generation of those species," Dr Jimenez-Guri said.

Explaining how plastics cause developmental abnormalities, Dr Jimenez-Guri said plastics contain a complex variety of potentially harmful components including zinc in this case -- which are slowly released once plastic is in the water.

She added: "If we reach these extreme levels of plastic pollution at our coasts -- which happens in isolated cases but is thankfully uncommon at present -- many species may become unable to reproduce, with massive impacts for marine life, the wider environment and people.

"We need urgent action to reduce the amount of plastic entering the ocean."

https://www.sciencedaily.com/releases/2024/04/240416125308.htm

[kassy]

Microplastics make their way from the gut to other organs


It's happening every day. From our water, our food and even the air we breathe, tiny plastic particles are finding their way into many parts of our body.

But what happens once those particles are inside? What do they do to our digestive system?

In a recent paper published in the journal Environmental Health Perspectives, University of New Mexico researchers found that those tiny particles -- microplastics -- are having a significant impact on our digestive pathways, making their way from the gut and into the tissues of the kidney, liver and brain.

...

"Over the past few decades, microplastics have been found in the ocean, in animals and plants, in tap water and bottled water," Castillo, says. "They appear to be everywhere."

Scientists estimate that people ingest 5 grams of microplastic particles each week on average -- equivalent to the weight of a credit card.

While other researchers are helping to identify and quantify ingested microplastics, Castillo and his team focus on what the microplastics are doing inside the body, specifically to the gastrointestinal (GI) tract and to the gut immune system.

Over a four-week period, Castillo, postdoctoral fellow Marcus Garcia, PharmD, and other UNM researchers exposed mice to microplastics in their drinking water. The amount was equivalent to the quantity of microplastics humans are believed to ingest each week.

Microplastics had migrated out of the gut into the tissues of the liver, kidney and even the brain, the team found. The study also showed the microplastics changed metabolic pathways in the affected tissues.

"We could detect microplastics in certain tissues after the exposure," Castillo says. "That tells us it can cross the intestinal barrier and infiltrate into other tissues."

Castillo says he's also concerned about the accumulation of the plastic particles in the human body. "These mice were exposed for four weeks," he says. "Now, think about how that equates to humans, if we're exposed from birth to old age."

The healthy laboratory animals used in this study showed changes after brief microplastic exposure, Castillo says. "Now imagine if someone has an underlying condition, and these changes occur, could microplastic exposure exacerbate an underlying condition?"

He has previously found that microplastics are also impacting macrophages -- the immune cells that work to protect the body from foreign particles.

In a paper published in the journal Cell Biology & Toxicology in 2021, Castillo and other UNM researchers found that when macrophages encountered and ingested microplastics, their function was altered and they released inflammatory molecules.

... more:

https://www.sciencedaily.com/releases/2024/04/240415163703.htm

[kassy]

PLASTIC IS STARTING TO GENERATE A STAGGERING PROPORTION OF EARTH'S CARBON POLLUTION

...

The scientists found that even a conservative scenario — of the plastic sector growing at 2.5 percent per year — would result in a future in which greenhouse gas emissions from plastic production could more than double by 2050 and make up 21 to 26 percent of the planetary carbon budget that keeps temperatures below 1.5 degrees Celsius.

A less conservative scenario — in which the plastic sector grows by four percent per year — would see greenhouse gas emissions increasing three fold by 2050, making up a staggering 25 to 31 percent of the planetary carbon budget to keep warming at 1.5 degree Celsius.

...

https://futurism.com/the-byte/plastic-earth-carbon-pollution

https://energyanalysis.lbl.gov/publications/climate-impact-primary-plastic

[Freegrass]

Yeah, we definitely need more plastic. 
Thank God we have less pollution now...

Look at the tiny people in the back. 

[Freegrass]

Why recycling plastics is just another scam from the FF fuel industry.

[morganism]

(putting it out there in the wild, hope this doesn't backfire.

Researchers make a plastic that includes bacteria that can digest it

Bacterial spores strengthen the plastic, then revive to digest it in landfills.

One reason plastic waste persists in the environment is because there's not much that can eat it. The chemical structure of most polymers is stable and different enough from existing food sources that bacteria didn't have enzymes that could digest them. Evolution has started to change that situation, though, and a number of strains have been identified that can digest some common plastics.

An international team of researchers has decided to take advantage of those strains and bundle plastic-eating bacteria into the plastic. To keep them from eating it while it's in use, the bacteria is mixed in as inactive spores that should (mostly—more on this below) only start digesting the plastic once it's released into the environment. To get this to work, the researchers had to evolve a bacterial strain that could tolerate the manufacturing process. It turns out that the evolved bacteria made the plastic even stronger.
Bacteria meet plastics

Plastics are formed of polymers, long chains of identical molecules linked together by chemical bonds. While they can be broken down chemically, the process is often energy-intensive and doesn't leave useful chemicals behind. One alternative is to get bacteria to do it for us. If they've got an enzyme that breaks the chemical bonds of a polymer, they can often use the resulting small molecules as an energy source.

The problem has been that the chemical linkages in the polymers are often distinct from the chemicals that living things have come across in the past, so enzymes that break down polymers have been rare. But, with dozens of years of exposure to plastics, that's starting to change, and a number of plastic-eating bacterial strains have been discovered recently.
Advertisement

This breakdown process still requires that the bacteria and plastics find each other in the environment, though. So a team of researchers decided to put the bacteria in the plastic itself.

The plastic they worked with is called thermoplastic polyurethane (TPU), something you can find everywhere from bicycle inner tubes to the coating on your ethernet cables. Conveniently, there are already bacteria that have been identified that can break down TPU, including a species called Bacillus subtilis, a harmless soil bacterium that has also colonized our digestive tracts. B. subtilis also has a feature that makes it very useful for this work: It forms spores.

This feature handles one of the biggest problems with incorporating bacteria into materials: The materials often don't provide an environment where living things can thrive. Spores, on the other hand, are used by bacteria to wait out otherwise intolerable conditions, and then return to normal growth when things improve. The idea behind the new work is that B. subtilis spores remain in suspended animation while the TPU is in use and then re-activate and digest it once it's disposed of.
(snip)
This doesn't mean our plastics problem is solved. Obviously, TPU breaks down relatively easily. There are lots of plastics that don't break down significantly, and may not be compatible with incorporating bacterial spores. In addition, it's possible that some TPU uses would expose the plastic to environments that would activate the spores—something like food handling or buried cabling. Still, it's possible this new breakdown process can provide a solution in some cases, making it worth exploring further.

Nature Communications, 2024. DOI: 10.1038/s41467-024-47132-8

https://arstechnica.com/science/2024/04/researchers-make-a-plastic-that-includes-bacteria-that-can-digest-it/#p3

[kassy]

Every breath you take: Study models the journey of inhaled plastic particle pollution

With recent studies having established the presence of nano and microplastic particles in the respiratory systems of both human and bird populations, a new University of Technology Sydney (UTS) study has modelled what happens when people breathe in different kinds of plastic particles and where they end up.

Led by Senior Lecturer of Mechanical Engineering Dr Suvash Saha, the UTS research team has used computational fluid-particle dynamics (CFPD) to study the transfer and deposition of particles of different sizes and shapes depending on the rate of breathing.

The results of the modelling, published in the journal Environmental Advances, have pinpointed hotspots in the human respiratory system where plastic particles can accumulate, from the nasal cavity and larynx and into the lungs.

Dr Saha said evidence was mounting on the significant impact of nano and microplastics on respiratory health and the UTS study would provide essential insights for the development of targeted strategies to mitigate potential risks and ensure effective health interventions.

"Experimental evidence has strongly suggested that these plastic particles amplify human susceptibility to a spectrum of lung disorders, including chronic obstructive pulmonary disease, fibrosis, dyspnea (shortness of breath), asthma, and the formation of what are called frosted glass nodules," Dr Saha said.

"Plastic particle air pollution is now pervasive and inhalation ranks as the second most likely pathway for human exposure.

"The primary types are intentionally manufactured, including a wide array of cosmetics and personal care products such as toothpaste.

"The secondary ones are fragments derived from the degradation of larger plastic products, such as water bottles, food containers and clothes.

"Extensive investigations have identified synthetic textiles as a principal source of indoor airborne plastic particles, while the outdoor environment presents a multitude of sources encompassing contaminated aerosols from the ocean to particles originating from wastewater treatment."

Dr Saha said the UTS team's modelling found that breathing rate along with particle size and shape determined where in the respiratory system plastic particles would be deposited.

"Faster breathing rates led to heightened deposition in the upper respiratory tract, particularly for larger microplastics, whereas slower breathing facilitated deeper penetration and deposition of smaller nanoplastic particles," he said.

"Particle shape was another factor, with non-spherical microplastic particles showing a propensity for deeper lung penetration compared to spherical microplastics and nanoplastics, potentially leading to different health outcomes.

https://www.sciencedaily.com/releases/2024/05/240501091658.htm

[morganism]

( a new depolymerization tech used on lignin and CO2 based carbon. This is a beautiful setup. simple catalysts help too.)


A closed-loop process for making and recycling polycarbonate plastic also captures carbon to reduce waste and cut emissions.

Amid mounting concerns over the state of the climate and environment, significant efforts have been spent developing innovative solutions to reduce plastic waste and capture carbon dioxide from the atmosphere — most addressing one crisis at a time.

However, researchers have recently devised a sustainable, closed-loop process for producing and recycling polycarbonate plastic while also capturing carbon, effectively addressing the two challenges simultaneously.

Conventional plastics recycling is a mechanical process that involves sorting, cleaning, and granulating the plastic into flakes before heating it at high temperature, and not all plastics can be recycled in this way — though it is more environmentally friendly than incineration or landfill disposal.

“However, [mechanical recycling] has a critical issue because repeated exposure to high heat can cause permanent changes in the chemical structure of the plastic, resulting in poor-quality recycled plastics,” explained Hoyong Chung, a professor at Florida State University and scientist on the current study.

Using lignin waste to make new plastics

The recycling method developed by Chung and his post-doctoral researcher, Arijit Ghorai, fundamentally differs from mechanical recycling. It involves converting polycarbonate into its original building blocks in a process known as depolymerization.

Key to this process is lignin, a major component of biomass which is now being recognized for its potential to at least partially replace fossil fuels in the production of plastics and other commercial products owing to its renewability, broad market, and low cost. It’s also a major unwanted byproduct of the biofuel and pulp and paper industries, where the latter generates approximately 50–70 billion tons of lignin annually. Much of this lignin goes to waste.

The “waste to wealth” concept isn’t new. Scientists have been turning all kinds of normally discarded debris, such as avocado pruning residue and metal shavings, into useful products like plastics and hydrogen fuel.

Chemists have also known for decades that carbon dioxide can be transformed into polycarbonate plastics, but the traditional process isn’t the most sustainable. Typically, carbon dioxide is reacted with fossil fuel-derived compounds, and the reaction not only requires high temperatures and pressures — meaning high energy expenditure — but also meticulously designed metal catalysts, which adds complexity to the process and also monetary costs, depending on the metal used.

To make this process more sustainable, Chung and Ghorai used lignin instead of a fossil fuel-derived starting material as well as a metal-free catalyst. Lignin is a good alternative because its chemical structure is rich in functional groups that can react with carbon dioxide in the presence of a suitable catalyst.

This reaction, which the researchers catalyzed using an organic molecule, produces cyclic carbonate, the building block or “monomer” of polycarbonate. The second step, the polymerization of cyclic carbonate into polycarbonate, can be done at room temperature and normal atmospheric pressure — much milder conditions than those required for the conventional synthesis.

By adjusting the catalyst, catalyst amount, and reaction time, the properties of the plastic, such as its thermal stability and strength, can be controlled, allowing the polycarbonate to be customized for specific applications. After its intended use, it can then be recycled via depolymerization, where the plastic is converted back into its monomer.

A circular plastic economy

Chemical recycling, the umbrella term for depolymerization and other technologies that convert plastic waste into its basic units to recreate the same product, and chemical upcycling, which is the conversion of plastic waste into products of higher value, seem to be the missing link in transitioning to a circular plastics economy.

Chung and Ghorai’s chemical recycling approach was relatively simple — to obtain the original cyclic carbonate, they heated polycarbonate at 90 °C for 12 hours using the same organic catalyst to speed up the depolymerization reaction.

“We can use these recycled monomers to resynthesize the original, high-quality polymer,” Ghorai explained. “By adopting this method, we can avoid any degradation in polymer quality after recycling.”   

“[Ideally], the developed polycarbonates are capable of undergoing [repeated] closed-loop recycling without compromising their original properties,” he pointed out. 

Ghorai and Chung confirmed through analyses that the properties of the recycled polymer were identical to those of the original, pristine polymer. However, more tests are needed to determine how many times the polymer can actually be recycled without degrading.
(more)

https://www.advancedsciencenews.com/new-plastic-recycling-method-captures-carbon/


CO2 and Lignin-Based Sustainable Polymers with Closed-Loop Chemical Recycling

This work highlights the conversion method of chaining up greenhouse gas CO2 with biomass lignin to develop new sustainable, recyclable polymers from abundant and non-food based renewable resources. A cyclic carbonate monomer has synthesized using a cost-effective, non-phosgene-based, and greener approach under atmospheric pressure and room temperature. The fully programable ring-opening polymerization is accomplished by varying the catalyst (DBU and TBD), catalyst loading (0.5–5.0%) and reaction time (2–40 min). The best polymer is obtained in 1% TBD with a 30-min reaction. The precise characterization of the synthesized cyclic carbonate monomer and polymers' structure are established using spectroscopic analyses including 1H, 13C, and 2D HSQC NMR, FT-IR, and GPC. The new polymers exhibit high molecular weights (Mn: 120.34–154.58 kDa) and adequate thermal stabilities (Td5%: 244–277 °C from TGA and Tg: 33–52 °C from DSC), rendering them advantageous for practical applications. Significantly, the CO2 and lignin-based polymers have successfully recycled to the monomer for a circular plastic economy by heating at 90 °C for 12 h in the presence of DBU. This process yields original monomers for another polymerization without unwanted changes in chemical structures, presenting an ultimate sustainable solution.

https://onlinelibrary.wiley.com/doi/10.1002/adfm.202403035