"Just One Word: Microplastics"

[Recusant]

This may be good news on the "humans ingesting plastic" front, though it seems unlikely to do much good for the rest of the planet.

"New Technique Removes More Than 98% of Nanoplastics From Water" | Science Alert

No one yet knows what threat plastic pollution poses to human health, but the recent realization that we are drinking invisible fragments of plastic along with our water is making many understandably uneasy.

To stop microplastics and nanoplastics from penetrating deep into our bodies and brains, researchers at the University of Missouri have come up with a potentially sustainable and safe way to rid water of microscopic pollutants.

Using natural liquid ingredients that have low toxicity, the team has shown they can remove around 98 percent of nanoscopic polystyrene beads from fresh and salt water.

The solvent that researchers engineered floats on the surface of water, kind of like oil. A quick mix, however, and – voila! – the liquid picks up microscopic plastics in the water and carries them to the surface.

Sucking up the top layer of liquid with a pipette, the team at the University of Missouri (Mizzou) found they could remove nearly all nanoplastic beads from their contaminated water samples.

In salt water, the method worked at extracting 99.8 percent of all polystyrene pollutants.

The proof of concept showcases a cost-effective and potentially "sustainable solution to the nanoplastics problem", argue researchers from Mizzou. With further research, the technique could even prove useful for cleaning water of other pollutants, like forever chemicals.

[Continues . . .]

The paper is behind a paywall.

Abstract:

Nanoplastics pollution, a growing environmental threat, adversely affects ecosystems and human health. The challenge in extracting and detecting nanoplastics from environmental matrices lies in their minuscule sizes, varied shapes, and low concentration.

We demonstrate an efficient approach employing hydrophobic deep eutectic solvents (HDESs) for the liquid/liquid extraction of polystyrene (PS) beads (nominally sized 0.1, 0.2, 0.3, 0.5, and 1.0 μm), a stand-in for nanoplastics, from both fresh and saline water. Of ten different HDES systems evaluated, those described by 1:2 molar ratios of tetrabutylammonium bromide ([N₄₄₄₄]Br):decanoic acid or tetraoctylammonium bromide ([N₈₈₈₈]Br):decanoic acid as well as 1:1 thymol:menthol showed exceptional efficiency, achieving nearly complete removal (a mean extraction efficiency of 98.4%) of nanoplastics in a single pass across a range of nanoplastic sizes from 100 to 1000 nm. The HDES comprising 1:2 [N₄₄₄₄]Br:decanoic acid exhibits a high extraction capacity, effectively capturing at least 17.2 wt % of PS. Crucially, the extractive fluids comprise benign components, and the hydrophobicity of these HDESs helps to prevent water phase contamination, showcasing their potential as a sustainable solution to the nanoplastics problem.

[Recusant]

This one isn't particularly surprising. If anything I'm surprised that it's the first time microplastics have been observed in human brains.

"Microplastics are in our brains. How worried should I be?" | The Conversation

A study from the United States has, for the first time, found microplastics in human brains. The study, which has yet to be independently verified by other scientists, has been described in the media as scary, shocking and alarming.

[. . .]

The study looked at concentrations of microplastics in 51 samples from men and women set aside from routine autopsies in Albuquerque, New Mexico. Samples were from the liver, kidney and brain.

These tiny particles are difficult to study due to their size, even with a high-powered microscope. So rather than trying to see them, researchers are beginning to use complex instruments that identify the chemical composition of microplastics in a sample. This is the technique used in this study.

The researchers were surprised to find up to 30 times more microplastics in brain samples than in the liver and kidney.

They hypothesised this could be due to high blood flow to the brain (carrying plastic particles with it). Alternatively, the liver and kidneys might be better suited to dealing with external toxins and particles. We also know the brain does not undergo the same amount of cellular renewal as other organs in the body, which could make the plastics linger here.

The researchers also found the amount of plastics in brain samples increased by about 50% between 2016 and 2024. This may reflect the rise in environmental plastic pollution and increased human exposure.

The microplastics found in this study were mostly composed of polyethylene. This is the most commonly produced plastic in the world and is used for many everyday products, such as bottle caps and plastic bags.

[. . .]

To get into brain tissue, microplastics must cross the blood-brain-barrier, an intricate layer of cells that is supposed to keep things in the blood from entering the brain.

Although concerning, this is not surprising, as microplastics must cross similar cell barriers to enter the urine, testes and placenta, where they have already been found in humans.

[. . .]

Microplastics are widespread in the environment, and it's difficult to avoid exposure. We are just beginning to understand how microplastics can affect our health.

Until we have more scientific evidence, the best thing we can do is reduce our exposure to plastics where we can and produce less plastic waste, so less ends up in the environment.

An easy place to start is to avoid foods and drinks packaged in single-use plastic or reheated in plastic containers. We can also minimise exposure to synthetic fibres in our home and clothing.

[Link to full article.]

The preprint version of the paper is open access:

"Bioaccumulation of Microplastics in Decedent Human Brains Assessed by Pyrolysis Gas Chromatography-Mass Spectrometry" | NIH/National Library of Medicine

Abstract:

Rising global concentrations of environmental micro- and nanoplastics (MNPs) drive concerns for human exposure and health outcomes. Applying pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) methods to isolate and quantify MNPs from human samples, we compared MNP accumulation in kidneys, livers, and brains.

Autopsy samples from the Office of the Medical Investigator in Albuquerque, NM, collected in 2016 and in 2024, were digested for Py-GC/MS analysis of 12 polymers. Brains exhibited higher concentrations of MNPs than liver or kidney samples. All organs exhibited significant increases from 2016 to 2024.

Polyethylene was the predominant polymer; the relative proportion of polyethylene MNPs was greater in brain samples than in liver or kidney. Transmission electron microscopy verified the nanoscale nature of isolated particles, which largely appeared to be aged, shard-like plastics remnants across a wide range of sizes. Results demonstrate that MNPs are selectively accumulated into the human brain and concentrations are rising over time.

[Recusant]

On the more hopeful side . . .

"New 'Living Plastic' Self-Destructs Once It's Thrown Away" | Science Alert

Scientists have created a 'living plastic' that self-destructs when the material begins to erode.

In the composting process, the novel product breaks down within a month, compared with more traditional versions that take up to 55 days to decompose under the same conditions.

The hopeful technology was inspired by the power of plastic-munching proteins, which are naturally produced by a species of bacteria discovered in 2016 at a recycling facility in Japan.

In the years since scientists have found several other species of bacteria that have evolved the enzymes to eat plastic, and these natural proteins have inspired synthetic versions that are even hungrier for our waste.

Researchers at the Chinese Academy of Sciences (CAS), led by synthetic biologist Chenwang Tang, have now figured out how to bake bacterial spores that secrete these enzymes into the very structure of polycaprolactone (PCL) plastic.

That way, when the plastic begins to degrade, these newly freed enzymes can finish off the task.

[Continues . . .]

The paper is behind a paywall.

Abstract:

Plastics are widely used materials that pose an ecological challenge because their wastes are difficult to degrade. Embedding enzymes and biomachinery within polymers could enable the biodegradation and disposal of plastics. However, enzymes rarely function under conditions suitable for polymer processing.

Here, we report degradable living plastics by harnessing synthetic biology and polymer engineering. We engineered Bacillus subtilis spores harboring the gene circuit for the xylose-inducible secretory expression of Burkholderia cepacia lipase (BC-lipase). The spores that were resilient to stresses during material processing were mixed with poly(caprolactone) to produce living plastics in various formats. Spore incorporation did not compromise the physical properties of the materials. Spore recovery was triggered by eroding the plastic surface, after which the BC-lipase released by the germinated cells caused near-complete depolymerization of the polymer matrix.

This study showcases a method for fabricating green plastics that can function when the spores are latent and decay when the spores are activated and sheds light on the development of materials for sustainability.

[Recusant]

I've missed posting a few items on this beat the past few months--none of them particularly encouraging. This one may at least be helpful. Cutting to the chase: boil it then filter it--even just boiling it can help.

"There's a Surprisingly Easy Way to Remove Microplastics From Drinking Water" | Science Alert

Tiny fragments of microplastics are making their way deep inside our bodies in concerning quantities, significantly through our food and drink.

Scientists have recently found a simple and effective means of removing them from water.

A team from Guangzhou Medical University and Jinan University in China ran tests on both soft water and hard tap water (which is richer in minerals).

"Tap water nano/microplastics (NMPs) escaping from centralized water treatment systems are of increasing global concern, because they pose potential health risk to humans via water consumption," write the researchers in their paper, published in February.

They added in nanoplastics and microplastics before boiling the liquid and then filtering out any precipitates.

In some cases, up to 90 percent of the NMPs were removed by the boiling and filtering process, though the effectiveness varied based on the type of water.

Of course the big benefit is that most people can do it using what they already have in their kitchen.

"This simple boiling water strategy can 'decontaminate' NMPs from household tap water and has the potential for harmlessly alleviating human intake of NMPs through water consumption," write biomedical engineer Zimin Yu from Guangzhou Medical University and colleagues.

[Continues . . .]

The paper is behind a paywall.

Abstract:

Tap water nano/microplastics (NMPs) escaping from centralized water treatment systems are of increasing global concern, because they pose potential health risk to humans via water consumption. Drinking boiled water, an ancient tradition in some Asian countries, is supposedly beneficial for human health, as boiling can remove some chemicals and most biological substances. However, it remains unclear whether boiling is effective in removing NMPs in tap water.

Herein we present evidence that polystyrene, polyethylene, and polypropylene NMPs can coprecipitate with calcium carbonate (CaCO3) incrustants in tap water upon boiling. Boiling hard water (>120 mg L–1 of CaCO3) can remove at least 80% of polystyrene, polyethylene, and polypropylene NMPs size between 0.1 and 150 μm. Elevated temperatures promote CaCO3 nucleation on NMPs, resulting in the encapsulation and aggregation of NMPs within CaCO3 incrustants. This simple boiling-water strategy can "decontaminate" NMPs from household tap water and has the potential for harmlessly alleviating human intake of NMPs through water consumption.

[Asmodean]

...How would boiling remove microplastics? I mean, I suppose some plastics could be degraded by high temperature, or are we talking different sort of mechanics here? (Physics rather than chemistry? I noticed coprecipitation - do them particles sort of... Rise up, boil off, then end up in your lungs rather than stomach..?)

I may need to actually read-read that thing. Interesting.

[Recusant]

Back to the routine "Eh, it's not good" caper . . .      << Standing in for something more sardonic. A good friend of long acquaintance whose hobby is show business has a thing called "The Laughter of the Gods." It's just wordless laughter and snide snickers but he does it in such a way that you know the gods are inherently cruel and that the suffering of humanity amuses them to no end. It's an intense performance, but I've seen him keep it up for at least a couple of minutes. I always admired his ability to transform his pain into a heartfelt mocking of human mythology and the element of pathos in our existence. I don't think it ever failed to get me laughing. At least for a while.

Again, meanwhile, back at the ranch . . .

"Nanoplastics Stick to Toxic Bacteria, Forming a Deadly Combination" | Science Alert

We're all awash in plastic fragments, with many of the smallest particles ranging in size from a micrometer down to a single nanometer across.

The health effects of these tiny 'nanoplastics' are still largely unknown, but the infinitesimal size and environmental abundance of them makes these synthetic fragments a potentially outsized threat – and not just for humans. In fact, not even just for organisms with cells as complex as ours.

According to a new study, nanoplastics also seem to cause stress for pathogenic E. coli bacteria.

That might sound helpful for us, in a "the enemy of my enemy is my friend" sense, but it isn't that simple, the study suggests.

Nanoplastics did not significantly affect the survival of E. coli, although they did affect other traits of the bacteria, such as biofilm development and overall growth. Perhaps most importantly for us, exposure to nanoplastics apparently prompts E. coli to become more virulent.

The study offers a novel glimpse into this dynamic, says senior author Pratik Banerjee, a molecular microbiologist in the Department of Food Science and Human Nutrition at the University of Illinois Urbana-Champaign.

"Other studies have evaluated the interaction of nanoplastics and bacteria, but so far, ours is the first to look at the impacts of microplastics and nanoplastics on human pathogenic bacteria," Banerjee says.

The researchers focused on E. coli O157:H7 – a notorious pathogen often implicated in outbreaks of food poisoning – and made nanoplastics from polystyrene, a synthetic polymer and one of the most widely used plastic types.

They found that nanoplastics with a positively charged surface are more likely to cause physiological stress in this E. coli serotype, prompting a defensive response. The stressed bacteria make extra Shiga-like toxin, their characteristic illness-causing chemical.

[Continues . . .]

The paper is open access:

"Nanoplastics-mediated physiologic and genomic responses in pathogenic Escherichia coli O157:H7" | Journal of Nanobiotechnology

Abstract:

The widespread occurrence of microplastics (MP) and nanoplastics (NP) in the environment is commonly thought to negatively impact living organisms; however, there remains a considerable lack of understanding regarding the actual risks associated with exposure. Microorganisms, including pathogenic bacteria, frequently interact with MPs/NPs in various ecosystems, triggering physiological responses that warrant a deeper understanding.

The present study experimentally demonstrated the impact of surface-functionalized differentially charged polystyrene (PS) NPs on the physiology of human pathogenic Escherichia coli O157:H7 and their influence on biofilm formation. Our results suggest that charged NPs can influence the growth, viability, virulence, physiological stress response, and biofilm lifestyle of the pathogen.

Positively-charged NPs were found to have a bacteriostatic effect on planktonic cell growth and affect cellular viability and biofilm initiation compared to negatively charged and uncharged NPs. The transcriptomic and gene expression data indicated significant changes in the global gene expression profile of cells exposed to NPs, including the differential expression of genes encoding several metabolic pathways associated with stress response and virulence. Significant upregulation of Shiga-like toxin (stx1a), quorum sensing, and biofilm initiation genes was observed in NP-exposed biofilm samples.

Overall, exposure to NPs did not significantly affect the survival of pathogens but affected their growth and biofilm development pattern, and most importantly, their virulence traits.

[Icarus]

  Finnish microbiologist researcher, Tero Hisokaupplia, is on the trail of an preliminary solution to plastic waste. It comes to pass that one of the worst waste products is that of disposable diapers and feminine care products, all partly plastic, which needs some 200 years to degrade in the landfill.  The first ever disposable diaper is still in a landfill somewhere, it is claimed.

He and his associates have experimented with 100 variations of fungi found in mushrooms, along with other fungi.  Those fungi and bacteria are capable of breaking down polyethylene plastics.  The fungus has an elaborate name: pestalopilosis crospora. (spell corrector did not like those words)  Certain carbon elements are involved in both the fungi and the soiled diaper.

Here's hoping that our resident chem wizard Hermes will comment.  This could be for real, or it could be bullshit published by a clever con man.                                                             

[Dark Lightning]

Keep finding various things to dissolve things and we're going to stumble on a "universal solvent", then we'll all perish.  Probably along with overheating of the earth by the sun. Race to the finish! 

[Recusant]

Finnish microbiologist researcher, Tero Hisokaupplia, is on the trail of an preliminary solution to plastic waste. It comes to pass that one of the worst waste products is that of disposable diapers and feminine care products, all partly plastic, which needs some 200 years to degrade in the landfill.  The first ever disposable diaper is still in a landfill somewhere, it is claimed.

He and his associates have experimented with 100 variations of fungi found in mushrooms, along with other fungi.  Those fungi and bacteria are capable of breaking down polyethylene plastics.  The fungus has an elaborate name: pestalopilosis crospora. (spell corrector did not like those words)  Certain carbon elements are involved in both the fungi and the soiled diaper.

Here's hoping that our resident chem wizard Hermes will comment.  This could be for real, or it could be bullshit published by a clever con man.                                                           

I found a few stories about this. Looks like they've actually rolled out the product now. Some of the articles made claims that the fungus-loaded diapers will result in breakdown of plastics in landfills beyond the diapers. That may be a bit ambitious, but very cool if true.

"Packet of Fungi Inside New Diapers Breaks Them Down in Landfill Turning it to Mycelium" | Good News Network

Recent discoveries in microbial digestion of plastic have finally left the lab and entered the real world in the form of HIRO diapers, the world's first diaper manufactured to be eaten by fungi.

Every year, over 18 billion diapers are discarded into US landfills—and if they aren't manufactured with natural cellulose, then they're going to be there for 500 years, leaking microplastics and chemicals into the soil.

With that unfortunate truth out of the way, dig this dirty great news: a pair of serial entrepreneurs have developed diapers designed to be broken down into soil by fungi, and they're practically flying off the shelves.

Each HIRO MycoDigestible Diaper comes with a small packet of shelf-stable, plastic-eating fungi. Parents simply throw the packet away with the used diaper—no extra steps required.

Once the diaper reaches a landfill, the fungi activate in the presence of moisture and begin to break down the diaper's materials from the inside out. These fungi secrete enzymes that target and sever the carbon bonds in plastic, transforming the waste into mycelium and nutrient-rich soil over time.

[Continues . . .]