Oncologist Warns About Nanoplastics in the Human Body | Dr. Long | ALLATRA Global Research Center

[00:00:00] John

So welcome. My name is John Ahn, your host for the show. I'm a scientist as business director, and I also serve as a volunteer researcher with the ALLATRA Global Research Center. And together, on a volunteer basis, we explore some of the most pressing global issues like climate, geodynamics, and the environment. And the goal is to raise the awareness and encourage open dialogue so that we can move towards real solutions.

So today, we're beginning a series of conversations focused on one of the least visible but, perhaps, most pervasive environmental and public health challenges that's facing us. And we're talking about micro- and nanoplastics. These tiny particles are now found virtually everywhere on our planet, from the summit of Mount Everest to the depth of Mariana Trench and even the remotest regions like in Antarctica and the forests of Pyrenees.

And not surprisingly, these plastic particles are now present in our own bodies. And they're entering through the food that we eat, the water we drink, and even the air that we breathe. So this raises some of the fundamental questions, and that is: What happens when these particles enter our bodies? And how do they interact with cells and organelles? And what do we currently understand about the potential consequences to human health? And where should scientific research focus next?

So to explore these questions, I would now like to welcome our guest, doctor Jeffrey Long, who has spent many years in the medical field as a radiation oncologist. Doctor Long, welcome.

[00:01:30] Dr. Long

Well thank you. It's sure a pleasure to be here.

[00:01:33] John

So thanks for being here. And so we want to start with the kick off things with the first question. And that is how this topic is relatively new. But how did you first learn about it? When you first heard about it, what caught your attention? Did that make you realize that this was something that you should really pay attention to, that we shouldn't ignore about this issue?

[00:01:51] Dr. Long

Great question. Sure. I first became aware of micro- and nanoplastics the way a lot of clinicians do. Not from a [00:02:00] single headline, but from a gradual accumulation of credible findings that started to feel impossible to ignore.
It was years ago I saw those early reports describing microplastics in seafood and bottled water. And at that time, I filed it away as an environmental issue. But over time, the data began to move from out there to in here with detection of these particles in the human stool, lung, blood, and and even in the placenta tissue. Now that shifts matters because it reframes this from a distant environmental problem to a direct human exposure question.

What really caught my attention was the combination of ubiquity — it's all over — and biologic plausibility. Plastic is not simply inert. Many plastic products contain additives, plasticizers, stabilizers, flame retardants, pigments, you name it, and plastics also can carry chemicals that absorb onto their surface. And when you reduce something to a micro- or nano scale, the surface area increases dramatically. And the interface where chemistry meets biology becomes much more important.

And at this point, it becomes reasonable to ask whether chronic exposure to these substances can contribute to oxidative stress, inflammation, and other biologic effects that we already know are relevant to disease.

I guess to answer your question directly, the turning point for me was realizing that this is an exposure on a global scale. This affects all people regardless of where they live, what they eat, or what their occupation is.

As a physician, when you see an exposure that is widespread, chronic, and potentially biologically active and harmful, it raises the same question that we ask in medicine again and again: What are the long term consequences [00:04:00] and what can we do to understand and hopefully reduce harm?

[00:04:05] John

I think people started studying this topic… I think people started studying them about maybe like early 2000, but then about maybe like about five years ago the studies of micro- and nanoplastics and human health, they really started to pop up in mainstream media. And my question to you is, because you're in a medical field, from your perspective, what took people so long or what took scientists so long to recognize that these micro- and nanoplastics are a serious threat to human health? Like what took them so long to realize this?

[00:04:35] Dr. Long

You know, that's an excellent question. And like you said, jeez, it was all the way back to 2000. We started hearing about this. And yet here we are, more aware of it and talking about today. Well, I think there's several reasons it took so long to confront this problem.
First of all, micro- and especially nanoplastics are difficult to see and measure. For decades routine environmental and biomedical testing simply wasn't designed to detect particles at these tiny sizes, or to distinguish these tiny particles from background contamination, or identify polymer types reliably. Even now, results of these tests can differ depending on the method used. Variations in sample preparation, spectroscopy thresholds, and contamination controls—all these can change what is detected. Bottom line: when measurement is hard, recognition is slow.

But I think, number two, and importantly, plastics were widely assumed to be relatively inert. Public discussion focuses on visible pollution. I mean bags, bottles, ocean debris, fibers generated through wear and tear. The sort of nanoparticles really were lagging behind in the health care conversation because we really couldn't see them as obviously as other types of evident pollution. And so it wasn't immediately obvious. So yeah, we were slow [00:06:00] to pick up on this.

But I think thirdly, the science has been siloed, if you will. Environmental scientists, analytical chemists, toxicologists, clinicians and epidemiologists, each one of those areas of scholarly interest have held different parts of the puzzle. It really takes time and sustained funding to build the bridges needed to connect these environmental measures to human exposure, and then to tissue distribution, and then to biological effects.

[00:06:29] Dr. Long

And then finally, and most importantly, to clinical outcomes. But lastly, establishing causality is difficult now. Many of the diseases we worry about — cardiovascular disease, neurodegeneration, endocrine disruption, and certainly cancer risk — they're all multifactorial. And when you have a cause of these illnesses, they unfold in manifesting the diseases over many years. So establishing that a ubiquitous exposure contributes meaningfully that requires large, careful studies. The field, thank goodness, is now accelerating because detection methods have improved, and because the first wave of human findings have now made this question impossible to dismiss.

Well, yeah, but you know, what's interesting is I hope this encourages research. For example, it seems like the simplest study in the world would be to study populations where there's greatly increased, you know, nanoplastic environmental contamination, if you will, and compare that to populations where there's far less nanoplastic environmental exposure and just, you know, try to get some correlations and try to see if we can, you know – of course, that would be correlation – but try to, to make that difficult connection between correlation and causality.

So, you know, there really needs to be a lot more of even straightforward epidemiological studies, which would really help point us in the direction of studies to help nail down, you know, how concerned we should be and certainly what we can do [00:08:00] about it.

[00:08:00] John

Yeah. I'm glad that things are accelerating in the right direction. It's certainly very important. And you know, another question I had was even for myself, I constantly mix up intentionally or unintentionally. I constantly use the micro- microplastics and nanoplastics. Sometimes I use them together. Sometimes I use, you know, one or the other. So from your perspective, what besides the size, I mean, like microplastics are those less than, essentially, from micron to, you know, five millimeters. The nanoparticles are those less than one microns. What are the key differences between them? I mean, why does it matter? What does the size difference matter biologically? Is one concerning more than the other? Should we care about the size?

[00:08:39] Dr. Long

You know another great question. I too was confused about the nomenclature regarding size. I want to emphasize that size is not just a technical detail. It changes how these particles behave in the body.
Microplastics are larger particles in the size that's commonly discussed ranges from about one micrometer up to five micrometers, and they can still be ingested or even inhaled. Now, many will be likely eliminated from the body when they're ingested or inhaled, but some of these microplastics can be retained, especially if they lodge in the mucus membranes, the airways, or the intestinal tract. Microplastics also can carry as carriers for additives and for chemicals that they pick up from the environment.

Nanoplastics, speaking of size, are smaller. They're often described as being below one micrometer, and sometimes even way smaller than that in the size range of tens to hundreds of nanometers. Now, with that tiny, tiny scale, a few things happen that are biologically important. They can be taken up more readily by the cells in the body through what we call endocytosis, and they can act directly within the cell membranes. And in principle, they may cross biological barriers more easily.

For example, the blood-brain barrier, the placental barrier or the [00:10:00] in the lungs, the alveolar-capillary barrier. Their surface area relative to their mass is vastly higher than nanoplastics, which can increase reactivity and the likelihood of interacting with proteins, membranes and the bodily intracellular structure.

So from a medical perspective, nanoplastics are especially concerning because they're harder to measure, meaning we may be shockingly underestimating our exposure to them, and because their small size makes them more likely to interact at the level where disease begins. That's oxidative stress, inflammation, mitochondrial disruption, disruption, and potential effects, even on the DNA integrity and cell signaling. These are some serious biological effects.

Now, certainly microplastics matter too. But nanoplastics, I think, in my opinion, raises the stakes even higher because they potentially access biologic compartments of the body that larger particles cannot.

[00:11:00] John

Another question I had people talk about different methods to getting rid of these microparticles, micro- and nanoparticles from the body. But in your opinion, is it possible to get rid of them? Do these methods work? I mean, like some people talk about, yeah, cleaning out the blood by, by eating certain diet or having certain diets or having certain procedures, you can eliminate them from the body. But is it really effective? Because I mean, obviously, the micro- and nanoplastics, they're not good for the body. We want to get rid of them. But is this well studied in the medical field? I mean, are these methods effective? Like what's done in these bloggers, what they talk about, are these effective in your opinion?

[00:11:37] Dr. Long

The big picture here is environmental contributors to cancer risk. Now, in oncology, my medical specialty, we're familiar with the idea that cancer often emerges from a combination of genetic susceptibility and cumulative exposures over time.

Some exposures in the environment are obvious. I mean tobacco, smoke and certainly certain environmental [00:12:00] chemicals and ionizing radiation. But others are subtler and operate through known pathways like chronic inflammation, oxidative stress, endocrine disruption, immune dysregulation, and interference with normal cellular repair.

Now, micro- and nanoplastics are concerning because they interact with several of those pathways in very plausible mechanisms. These particles themselves can provoke an inflammatory response — particularly when inhaled or when they interact with the immune cells. Inflammation and oxidative stress can increase the genomic instability and alter cellular signaling.

Now, in addition, the nanoplastics can contain or carry endocrine disrupting chemicals or other additives, and that can certainly influence hormone sensitive tissues or immune function.

Now, another observation that's generated interest medically are reports of plastic particles in human tissues, and in some studies even within tumor with cancer specimens. Now, I want to emphasize the responsible scientific stance here is to be cautious. Finding particles in cancer tumors doesn't prove that they caused the tumor. Tumors are biologically unusual environments. They can have leaky vasculature, altered lymphatics, and high metabolic activity. So it's also possible that these cancers preferentially accumulate circulating particles like nanoparticles.

The key question here is whether exposure to microplastics’ nanoparticles meaningfully increases risks and if so, through which pathways and in which tissues? So my perspective as an oncologist is the hypothesis that micro and nanoplastics could contribute to the cancer risk is absolutely biologically plausible. But we really need stronger evidence to quantify how much they matter relative to other exposures, and to identify which tissues and pathways are most affected. [00:14:00]

[00:14:00] John

Yeah, I think this cancer is a pretty tricky topic because we don't really even without micro- and nanoplastics it's a pretty… we don't really understand it very well and then you complicate things with micro- and nanoplastics and people are finding, “Oh, by the way, there's more micro- and nanoplastics in, like, tumors or atherosclerosis and in plaques.” (Dr. Long: Yes) “Oh, what's going on?” It's very hard to link because we don't even understand the whole these diseases.

So I guess it's a very difficult topic to uncover since we don't even know it very well even without micro and nanoplastics, right? You're a radiation oncologist and obviously you have spent many, many years thinking about how these various external agents, including microplastics, interact with different biomolecules like DNA, proteins, cells and tissues. So, you know, now knowing a little bit about micro- and nanoplastics, how did it change the way you think about the cancer biology or cancer risks?

[00:14:56] Dr. Long

Yeah. You know, again, great questions. As a radiation oncology physician that treats cancer every day, there are a few plausible mechanisms by which micro or nanoplastics could actually influence the cancer treatment I give regularly. But I want to emphasize that the word here is emphasis is plausible because this is an emerging area, and we just simply need more direct and better quality clinical data. However, there's a lot of concerning possibilities. For example, one possibility relates to the tumor cancer microenvironment. Now the radiation response when we treat with radiation therapy is influenced by factors like oxygenation, baseline inflammation, vascular function, and immune activation. If chronic exposure to any of these particles contributes to systemic inflammation or alters immune signaling, it certainly could, in theory, shift how cancers and normal tissues respond to radiation therapy and actually other cancer treatment modalities, such as chemotherapy [00:16:00] and immunotherapy.

Now a second concerning possibility is the interaction with normal tissue and toxicity resulting from that. Now, in radiation oncology we think a lot about fibrosis, vascular energy and inflammatory cascades. These can unfold over months, even years after treatment. And if a patient has an additional inflammatory burden from any source, it can potentially affect recovery from treatment, symptom severity resilience. It can contribute to complications. [00:16:29] It's not that microplastics would change the physics of radiation therapy treatments, but they could certainly influence the biology of how tissues heal after treatment.
And then finally, a third angle is pharmacology. Now some nanoparticles are intentionally used, interestingly already in medicine to deliver drugs, but unintended particles in the body as environmental exposure is—that could potentially bind transport or concentrate chemicals in a way that we just don't yet fully understand. So whether that meaningfully affects treatment efficacy, we don't really know that, but it is absolutely a question that we need to continue studying and investigating.

And frankly, to me, it's worrisome. But practically what it changes for me right now is awareness and counseling. Patients ask what they can do. Now, I'm careful not to overstate what the science has proven, but I do think it is reasonable to encourage low risk exposure reduction steps. For example, avoid heating food in plastic, reduce the use of single plastics where feasible, and certainly pay attention to the quality of air and water filtration. These are common sense things that we can all do every day while we push the research forward to learn more.

[00:17:53] John

So using many types of cancers and in your practice, in your opinion, like what types of cancers are the most commonly [00:18:00] linked or perhaps caused by micro- and nanoplastics? And you know, I know this is an ongoing study. In your opinion, why is micro- and nanoplastics found more in tumors? I mean, people linked, for example, micro- and nanoplastics to tumors because more of these micro- and nanoplastics are found in tumors. So again, it doesn't, it's not the causality, but, is it that the micro- and nanoplastics are attracted to these tumors? Or is it that the micro- and nanoplastics are there in malignant cells and then they develop into tumors? I know this is an ongoing study, but yeah, I just want to get your opinion, what you're thinking personally on these issues.

[00:18:39] Dr. Long

The real answer is we need to learn a lot more. We need those studies that will help correlate the exposure to nanoplastic microparticles and find causality, exactly what kind of tumors it causes, how much, how serious that is, how much that adds to difficulty in curing cancers or controlling side effects of treatment. We really don't know yet.

We can't really, based on science so far, say that nanoplastics and nanoparticles cause specific types of cancers with, say, a specific percentage increased risk. But we do know there's a lot of concerns based on how they interact with the body, causing that inflammation, bringing in other chemicals from the environment, including chemicals from the environment that we know cause cancers.
So I'm very concerned about that. Many clinicians like myself are very concerned about that, but we just simply need to have more information, more studies before we can answer these very critical and frankly, potentially life-saving questions. You know, just exactly how serious is the impact? I think the impact is serious. We just can't quantify that at this time, unfortunately.

[00:19:51] John

You know, I mentioned this earlier that these studies are relatively new, and you obviously recognize that micro- and nanoplastics could be a potentially big issue [00:20:00] in your field. So from your perspective and from your experience, you know, how is the broader medical community responding to this? Are your colleagues in this field? Are they generally aware of the issues with micro- and nanoplastics? So are they skeptical or are they cautious or they're doing something proactively? What is it like? Is this issue with micro- and nanoplastics well-aware in your profession, among your colleagues?

[00:20:25] Dr. Long

Well, I wish I could say there's a lot of concern and a lot of awareness among the physicians that I work with every day, but that's simply not true. There's really not much awareness in the medical community in general among clinical practice providers about nanoplastics, about microparticles, all the things that we've been talking about here that we're so concerned about. So we have a lot of education to do. I want to emphasize, awareness of this problem is growing, but my gosh, it's not anywhere where it needs to be at this point in time.
Now, I want to emphasize most clinicians, doctors like myself, gosh, we're overwhelmed with immediate clinical demands. And medical education tends to lag behind emerging environmental science like we're talking today. I mean, we're really at the leading edge in talking about today, this significant, as I consider it to be, a significant threat to our health. Well, unless someone has a special interest in the medical field and environmental health, they're probably not going to be following the literature that we're talking about today closely. Now, even among those who are aware of this, the reaction is often cautious. They might say something “Wow, interesting, but is it clinically proven?” Well, okay, that's a fair question because medicine rightly demands strong evidence before we change practice or even make strong recommendations.

[00:21:48] Dr. Long

So what would help to raise awareness is high-quality synthesis and translation, not just individual studies, but what we really need medically are consensus statements, standardized definitions, [00:22:00] and clear summaries of what is known and likely what remains uncertain. And we can share that with the world in a very positive way.
And I think that that's probably the most important, significant thing that we could do. And this talk, frankly, is certainly help. But in the bigger picture, continuing medical education modules, grand round topics and inclusion in public health discussions would help enormously.

You know, I also think clinicians respond, sort of, like when there's a clear clinical hook, what the clinicians like me and others are looking for are validated biomarkers of exposure, some strong epidemiologic links to specific outcomes, or especially evidence-based guidance on effective mitigation of these risks. As those pieces develop over time, I can assure you the medical community's engagement in this important issue is going to increase, it's going to accelerate. So in the meantime, I would phrase this as an absolutely legitimate but emerging public health concern that absolutely deserves attention without sensationalism.

[00:23:07] John

Yeah. And one of the tricky things that you mentioned is there's an analytical method. I mean, when people are studying oceans, people are collecting, like, with nets with cods, I mean they have to use a certain method. And then they analyze it and they would get, I don't know, like they would basically find a distribution where you have a large particle here, smaller particle here, it would kind of go like this and then and down. But then recently they started to collect different methods and then they study it with spectroscopy so they can measure all these nanoplastics. And then well, voila, you see, like it's actually going exponentially as you go smaller and smaller, which really makes sense. And we have missed all this in, for example, the oceans. Yeah, definitely, one of the challenges is the analytical method. We don't even have a good method to measure these small particles. I mean, let alone how do you get, how do you sample it from the body? That's another question. [00:24:00] So yeah, a lot of challenges.

[00:24:02] Dr. Long

A lot of this comes down to funding. You know, that's what drives research is, you know, getting it would be fairly substantial funding that would be necessary to get the proper equipment, calibrate it, rely on the results. And I just don't think there's enough people that are interested in that or seeking funding or there's a lack of funding availability. But a lot of it comes down to that. Like I said, I just hope we don't find out 20 years from now that we should have thought about something, you know, nanoplastics a lot more seriously today than, you know, later when we find out it's causing problems. So yeah, it's tough. I hope this spurs some interest in some scientists doing the kind of studies that are really going to move progress forward in these critical understandings.

[00:24:52] John

Yeah. Thanks for being in this podcast because, you know, one thing that we want to do is raise awareness by raising awareness, then we can have conversations and that can, you know, start to move things in the right direction towards solutions.
So again, thanks for being here, Doctor Long. And just switching a topic a bit, you know, looking from a business angle, I would imagine that micro- and nanoplastics, since they're impacting health, sort of in a subtle way, but it is impacting everyone's health. So I would imagine that this is increasing the cost of health care. I mean, do you see this or is it not so obvious at this time? What is your opinion on this?

[00:25:29] Dr. Long

You raise an excellent point there. And I think that there is a very reasonable concern that micro- and nanoplastics absolutely could increase health care costs, even while we're still quantifying exactly how and how much they'll increase costs. Now, the main driver of this is the possibility of incremental contributions to chronic disease burden. If a ubiquitous exposure nudges the population risk upward for things like cardiovascular disease, metabolic disorders, respiratory inflammation, reproductive defects, [00:26:00] neuroinflammatory conditions, or even as we've been talking about cancer, well, the downstream healthcare costs can be enormous. Healthcare systems worldwide are already strained by chronic disease management, and even a small percentage increase at a population level can translate to a huge, major economic impact.

Now there's also the cost as we think about health care costs of diagnostic complexity, when, as so often happens, patients present with nonspecific symptoms, fatigue, inflammatory syndromes, worsening asthma, unexplained gastrointestinal issues. Clinicians often pursue extensive workup and expensive workups. Now, if environmental exposures are part of the causal web but not readily measured or addressed, we can end up downstream treating years from now effects of these exposures rather than upstream, like right now, causes — potentially what exactly what we've been talking about today, the nanoplastics.

Now, from a business and system standpoint, prevention is usually the best way to control costs by far. If improved standards and safer materials and better filtration, reduced exposure — if that can lower long term disease risk, that is not only a major cost-saving strategy for health care, but it also helps save health. It also helps save lives. And it's going to be the most cost-effective approach that we can do at this time today. So I would have to emphasize that we still need the science to define where the greatest risks are and what interventions, what things we can do today that would be most effective.

[00:27:49] John

Yeah. Again, this is why we're having this podcast. We would like to have this information as wide as possible because we want to raise the awareness because that's the first step towards a solution. And you know, to end this [00:28:00] episode, I want to ask you a final question that is, given what we know currently about micro- and nanoplastics and what we still don't know, what would you like to see happen next, both for the scientific community and for the society more broadly?

[00:28:14] Dr. Long

Oh, absolutely. That's so important. What I'd like to see most next is a focused, coordinated effort that moves us from detection and concern of these particles to measurement, causality, and ultimately mitigation, reducing the risk.

For the scientific community a few priorities stand out. First, we need standardized methods. There needs to be a scientific agreement on the definitions for micro- versus nano scale, validated laboratory protocols and rigorous contamination controls. So when we get the results of these studies, they can be comparable across different studies.

Second, we need more exposure assessment that is meaningful clinically, reliable measures of what people are actually taking in through everything that we encounter in our daily lives — air, water, water, diet, consumer products. We need to find out how that correlates with the biomarkers in the blood and the tissues.

But thirdly, we need mechanistic work that connects the exposure to the biologic effects. What's happening? There's so much that we need to know at the level of inflammation, oxidative stress, immune signaling, endocrine pathways, cellular injury, along with what we really need very importantly, critically at this time actually is well-designed longitudinal studies, [where] we follow people for years. And that can help address these critical issue of causality and dose response to these particles.

But for society more broadly, I think we need a balanced approach. We certainly need to, effective today, reduce unnecessary plastic use, improve waste management [00:30:00] and filtration, and incentivise materials and manufacturing processes that do not fragment into these persistent biologically active particles. The goal here is not to panic. [00:30:11] The goal here is, starting today, risk reduction based on evidence, if you will, and common sense.
But finally, we certainly need better communication. This podcast is extremely important. The public absolutely deserves clarity about what is known and what is not. So if we can continue to educate the public, just like we're doing right now, and push forward to align scientists, clinicians, policy makers, and responsible industry around transparent data and practical steps, we — you, me, everyone watching this video — all of us can make real progress. This is exactly the kind of an issue where a clear strategic vision, shared messaging, and sustained support can accelerate the path from research to very positive, life enhancing, real world solutions.

I can't think of right off the top of my head of a more difficult research topic than what we're talking about right now, given how I kept saying how ubiquitous it is, how it's so widespread. I mean, there's nothing you're not going to find a human on earth that has not been exposed to nanoplastics. So that's going to be a real challenge. And yet it's so important. I hope we don't start seeing a lot more cancer, cardiovascular disease, you know, worsening of chronic health conditions. And then find out 20 years from now, it was causal with nanoplastics, and we just didn't start the studies today. So I hope this creates awareness and hopefully moves the needle forward and understanding what the impact of these things are and what we can do about it today.

[00:31:48] John

Great. Thank you so much for sharing your insights and perspectives today Doctor Long. And it was really truly a pleasure to have you on the show. And we'll welcome you back in a future episode. So thanks. Thanks so much [00:32:00] for being here.
And to our listeners, thank you for tuning in and, you know, understanding and solving the global issues like micro- and nanoplastics begins with the conversations like this one. So if you're interested in learning more, I encourage you to watch the recent documentary. It's called “The Nanoplastics Threat to Life.” And by the way, which Doctor Long and I have both participated in. You'll find a link in the description of this episode. So until then, thank you for tuning in. And until next time.

[00:32:31] Dr. Long

That will be fascinating. I'll look forward to it. I learned a few things listening to the other speakers too. So super. All good.