Drip Feed

For every influencer trying to convince you that micro and nanoplastics are going to be the death of you, your loved ones, and everything in a 10 mile radius, there’s a stack of research that makes them sound like medieval peasants worrying about the end of days because of an eclipse. But they’re more concerned with selling you something than saying “well, the science is unclear about that.”

At the Right Filter, we focus on the science. Not just because we’re giant, unrepentant nerds, (which we are) but because, if you’re willing to read enough papers, the outlook looks more optimistic rather than pessimistic. So let’s get into it!

First, a team from Washington State University used lingin to substitute 20% of the fossil fuel based chemicals that are used in making polyurethane foam. That’s the foam they make mattresses out of. Since lignin is the 2nd most abundant renewable carbon source, and makes up about 30% of the non-fossil fuel-based carbon on Earth, that’s kind of a big deal for sustainability.

Now, usually, lignin is super difficult to extract from the plants it comes from. Because of that most lignin is either burned to produce fuel and electricity or used in low-value products, like cement additives or as a binder in animal feed.

But this team extracted the lignin with a mild, environmentally friendly solvent, and did it in a way that works better than the current methods. So, double win!

https://phys.org/news/2025-01-based-substitute-fossil-fuels-plastic.html

Next, a team at Cornell figured out a way to potentially solve the issue where tough plastics are harder to recycle. Which is kind of a serious issue because you don’t want a replacement hip to dissolve after it’s been implanted, or a car tire to come flying apart while you’re driving.

The class of plastics used in these applications are called thermosets and they’re known for extreme durability. They also make up about 15-20% of all the plastics made and they are impossible to recycle.

But this team used dihydrofuran, a chemical building block, to redesign how thermosets are made. This new method allows thermoset plastics to be recycled by heating it , after which it naturally degrades in the environment. Which is great!

https://phys.org/news/2025-01-durable-plastic-sustainability-makeover-polymerization.html

Next, a team of researchers from Kyungpook National University found a way to narrow down which naturally occurring microbial enzymes can degrade PET plastics. Now, scientists have already found a lot of these enzymes in bacteria, and they’ve already been modified for industrial applications. But the hunt is time consuming and difficult, so the work by these researchers can actually help us speed that along.

https://phys.org/news/2025-01-enzyme-profiling-method-candidates-plastic.html

Going one step further, researchers from the Horizon 2020 project called PROMICON have developed a method that uses cyanobacteria to produce PHA. Which is a type of bioplastic that fully degrades in soil, water, and marine environments.

Now, we’ve known how to use microorganisms to make PHA for a while, but scaling up its production remains a challenge because of how much water and organic raw materials are needed. But this specific method uses photosynthesis, so it uses sunlight, absorbs carbon dioxide, and doesn’t need nearly as much of those raw materials! And it also doesn’t generate microplastics!

https://phys.org/news/2025-01-highlights-photosynthetic-microorganisms-sustainable-bioplastic.html

Finally, and this one’s my favorite, science is never satisfied with just finding out new stuff, it always goes back and verifies previous assumptions.

See, for decades, polystyrene and polyvinyl chloride has been used in construction pipes, trash bags and credit cards. And for decades, the assumption was that since it didn’t break down in the sun, there wasn’t an easy way to break it down.

But researchers working with the American Chemical Society found that if you turn up the light high enough, and the stuff has enough carbon black, which is a pigment, it starts to break down naturally. Which was news to even the manufacturers of the stuff!

So what they found was that carbon black can depolymerize polystyrene and polyvinyl chloride. Now, the reason that’s important is that these two are the least recycled plastics in the waste stream. Through a process called photothermal conversion, intense light is focused on plastic containing the pigments and that jumpstarts the degradation.

To quote Assistant Professor of Chemistry Erin Stache, "The surprising thing, especially with the black polystyrene depolymerization, is that they've been manufacturing these materials for decades and it seems no one recognized that this was possible.”

So science tells us that things can be better, that the problems that got us here are solvable, and that even the problems we thought we understood can be reexamined.

At least if you’re willing to listen to the unrepentant nerds without agendas.

This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit therightfilter.substack.com

The more we look for plastic, the more we find. And we keep finding it in places that we really really didn’t expect to find it, in forms we weren’t expecting.

For example, when you think of the Great Pacific Garbage Patch, do you think of a bunch of plastic bags, maybe some gallon jugs mixed in there? Or do you think of a slightly thicker soupy area of the ocean? Because it’s closer to the latter.

And a lot of plastic pollution is like that soupy stuff, mostly micro and nano plastics rather than big visible chunky bits. To clarify, microplastics are generally bits of plastic smaller than 5mm, but nanoplastics are usually less than 1 micrometer. And, in context, 1 micrometer, or 1 micron, is 100 times smaller than the width of a human hair. And since nanoplastics are the result of larger plastics breaking down, the stuff is basically everywhere we look.

Recently, a bunch of mountain climbers took samples from high-altitude glaciers and they found nanoplastics in 5 of the 14 sites they sampled. The most common kinds of nanoplastics were tire wear particles (41%), polystyrene (28%), and polyethylene (12%).

https://phys.org/news/2025-01-mountaineers-scientists-nanoplastics-remote-glaciers.html

Another study found that when critters in the ocean eat plastics, and then poop them out, the plastic gets hidden inside the poop. Which means we are seriously undercounting how much plastic is on the ocean floor or in the bellies of creatures who eat the plastic filled poop.

https://phys.org/news/2025-01-marine-animals-consume-microplastic-particles.html

Sticking to the poop theme, another study showed that there was microplastics in the organic wastes used as fertilizer. To quote one of the researchers, "Even biodegradable plastics are not breaking down as expected, leading to their accumulation in soils. This raises concerns about the long-term impact of microplastics on soil health and productivity,"

https://phys.org/news/2025-01-microplastics-contaminate-environmental.html

So, it’s in the glaciers, in the oceans, and in the soil. Which, if it was completely harmless and didn’t interact with anything, wouldn’t be that big of a deal. But it definitely isn’t either of those things so…yikes.

But that doesn’t mean there isn’t hope or a solution on the horizon.

The Oak Ridge National Lab, under the Department of Energy, found a way to use the same technology as CRISPR on plastics. To quote Jeffrey Foster, "This is CRISPR for editing polymers…However, instead of editing strands of genes, we are editing polymer chains. This isn't the typical plastic recycling 'melt and hope for the best' scenario."

https://phys.org/news/2025-01-polymer-upcycle-higher-plastics.html

So while we keep finding the stuff, pretty much everywhere we look, there’s a possibility that someday we’ll have plastics that don’t generate nanoplastics, and that we’ll be using the Great Pacific Garbage Patch to make more plastics rather than letting it get bigger every year.

This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit therightfilter.substack.com

As we do more and more research on PFASs and their impact on humans, it helps to imagine the situation from the biggest scale to the smallest. On the smallest scale, we know that PFASs affect cells and genes. On the biggest, we find correlations between PFAS exposure and various health issues. For example, a recent study by the Keck School of Medicine of USC showed an increase in the rate of certain cancers that are correlated with exposure to PFASs.

https://medicalxpress.com/news/2025-01-links-pfas-contamination-range-rare.html

How much of an increase? Between 2 and 33 percent. And that’s without being able to measure the actual exposure and using a binary, yes/no, for PFAS exposure. Which is useful information but the problem is we’re still figuring out the stuff in the middle.

How much exposure is necessary to cause actual harm versus simply passing through the body without any major effect? No idea. How does a PFAS affect an individual and through what mechanisms? Still not totally clear.

Part of the problem is that it’s hard to get specific measures because our methods of sensing organic pollutants are crude. But a study by some scientists at Northwestern has shown that there’s a possible solution to that.

https://phys.org/news/2025-01-amplification-toxin-sensitive.html

By tweaking a sensing platform that’s being used to measure toxins in water, researchers have been able to measure chemicals at low enough concentrations to have use outside the lab. The tweak involves a little circuitry to amplify the signal. Sort of like how Dylan went electric and why Spinal Tap went to 11.

https://phys.org/news/2025-01-reverse-osmosis-membrane-biofouling.html

Measuring these pollutants is the first step. Removing them is the next one. And researchers at the Chinese Academy of Sciences are working on that one too. Recently, they developed a dual-functional reverse osmosis (RO) membrane with enhanced antibacterial and antiadhesion properties. The reason that’s so cool is that while RO is an incredibly wasteful and problematic method of filtration, it’s pretty much the only game in town for removing particularly stubborn things, like salt. But the current line of membrane technology all have a problem with increased energy consumption and operational costs caused by membrane fouling. Biofouling, when microbes and bacteria and other living things grow on the membranes, accounts for over 45% of the problem.

But, if the membrane itself is antibacterial and prevents adhesion, or stickiness, then these new membranes bypass that entire issue.

Another interesting trend in new technologies involves turning trash into treasure. For example, a team from University of Illinois Urbana-Champaign, found a way to make ethylbenzene—an additive that improves sustainable aviation fuels—from polystyrene, a hard plastic used in many consumer goods.

https://techxplore.com/news/2025-01-team-sustainable-aviation-fuel-additive.html

But let’s not hang our hats on new technology to be the solution to every problem. A macroanalysis from Kaunas University of Technology showed 5 key challenges to plastic recycling.

https://phys.org/news/2025-01-microplastics-macro-impact-expert-plastic.html

To quote the lead researcher, Artūras Torkelis, "Focusing solely on improving recycling technologies or finding new methods without considering economic, environmental and legal aspects would be a mistake. This approach won't just fail to solve the problem, it could also lead to shortfalls when considering other aspects,"

So while science keeps working on how PFASs affect humans, how to make saltwater into freshwater, and even how to turn trash into treasure, we have to remember that it’s a process. Learning how the economy, the environment, and the law could solve the problem more thoroughly than technology is also part of the process.

Science never offers easy answers, but the scientific method is still the best way to figure out the world around us and our place in it. But it’s up to us to figure out the best way to work together and make a better world for us all.

This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit therightfilter.substack.com

In spite of all the social media frothing at the mouth about PFAS, science continues its march. Recently, scientists have identified the 11 genes that are directly affected by PFASs and their siblings.

https://phys.org/news/2025-01-scientists-genes-affected-pfas-neurotoxicity.html

What this will eventually let us do is measure how much a human has been affected by these chemicals. See, we’ve managed to prove how they affect things in a lab setting, but the actual impact on something as big and complex as a human body is still in the category of “well, we’re not 100% sure”. But with this information, we might be able to figure that bit as well.

Which is good news because apparently we’ve been ignoring an entire class of forever chemicals. Specifically, the ones that are used in pharmaceuticals. See, the addition of fluorine allows medications to last longer in the body, which is good, but also allows the medication to survive outside the body when it’s excreted. So it ends up in the wastewater and back into the water cycle itself.

https://phys.org/news/2025-01-chemicals-wastewater-widespread-previously-reveals.html

And, in addition to the fishies getting a dose of your supplements, they also get more than their fair share of microplastics.

A recent study showed that only a tiny fraction of the microplastics in seafood come from how we harvest, process, package, and sell them. In fact, just rinsing your food takes care of that. The rest of the microplastics come from their environment and the food they eat.

https://phys.org/news/2025-01-microplastics-widespread-seafood-people.html

Which means the plastic bag is already in your fish, and so is any fluorine based medication. Which is why these next two studies are so important.

First is something that has been going on for a while but is moving slowly but surely towards widespread adoption. And that is the use of engineered bacteria to break down microplastics in wastewater.

https://phys.org/news/2025-01-bacteria-microplastics-wastewater.html

And, by using silk as a base for filtration membranes, another study found a far more efficient method of removing over 99% of organic pollutants in wastewater. Which includes PFASs!

https://techxplore.com/news/2025-01-silk-based-nanofiltration-membrane-purify.html

All this matters because we still don’t have a global treaty about plastic, its use, and its disposal.

https://phys.org/news/2025-01-failure-plastics-treaty-health-crisis.html

The issue isn’t just the generation and use of plastic itself, it’s also how we dispose of it. As it stands, we either bury it, burn it, or dump it in the ocean. But at least with the tweaked bacteria and silky smooth filters, we are moving towards keeping it out of the ocean.

You know, where the fishies live.

This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit therightfilter.substack.com