How Worried Should We Be About Glyphosate? | Michael Antoniou

0:00Dr Karan: There's growing fear surrounding the world's most popular weed killer, glyphosate. From cancer to hormone disruption, how worried should we really be? That's what I'm discussing with Professor Michael Antoniou, as well as his thoughts on genetically modified foods.

0:18Dr Karan: I'm Dr Karan, and in this podcast, I speak to the world's foremost experts in science and medicine to cut through the BS of modern health advice. Thanks as always to Throne Science, the world's first hands-free, continuous smart toilet platform that can track your gut health, prostate health, and hydration with every flush. Thank you for sponsoring the show, as well as Loam, the world's first six-in-one invisible fiber blend that's also clinically backed. Professor Michael Antonio, a lot of people have heard about the word glyphosate, but what does it actually do as a pesticide and why is there concern around it?

0:52Right, well that's obviously a very big question. I'll begin by defining what glyphosate is. So glyphosate is what's known as a broad spectrum herbicide in that the mechanism through which it works, and I'll describe that in just a minute, it exists in all plants and therefore it kills all plants. And it does so very, very effectively. And it was launched as an agricultural herbicide weed killer in 1974 by Monsanto company in the United States. They discovered it had this weed killing properties. As a chemical, it was discovered back in the 1950s, but nobody really knew what to do with it very much.

1:37Although it was found, and I mentioned this now because it is important from a health perspective as well. What glyphosate was originally found to be able to do back in the 1950s was to bind metals, what's known as a metal chelator, metal binder, but that includes nutrient metals like magnesium, calcium, manganese. And of course, when it binds these, for example, in the soil, in the plant, it makes them unavailable for an organism to utilize. So it can have through this mechanism have implications for soil health, plant health. And of course, if a human ingests sufficient amounts of it, probably not, it could even compromise utilization of these nutrient minerals for consumers.

2:27But this is not an insignificant, but a rather minor effect of the glyphosate herbicides. So the main mechanism by which glyphosate kills plants, acts as a weed is inhibits a biochemical pathway known as the shikibate pathway. It doesn't really matter what it's called, but it's a biochemical pathway that's absolutely essential in plants because it synthesizes essential amino acids, aromatic amino acids, tryptophan, for example, tyrosine. And when glyphosate blocks this biochemical pathway, the plant can't synthesize it, these essential aromatic amino acids and it dies and it dies relatively quickly because this shikimate biochemical pathway is absent in animals and humans it was originally touted by the industry monsanto and company that glyphosate is absolutely safe for humans so this is why it was touted as better and safer than older herbicides absolutely right it was safer and better.

3:39It was more an effective weed killer, but safer because of the different biochemistry through which it killed plants, which was absent in animals and humans. Now, what the industry failed to say at that time was, firstly, this shikimate pathway is maybe absent in yours and my body cells, but it is present in a very high percentage of the bacteria of our gut microbiome. Wow, okay. So it could create inhibition there and create an imbalance in the gut microbiome through that mechanism, potentially. And the other point that industry failed to mention was that glyphosate can exert toxicity through other mechanisms, not through inhibition of shikimate pathway.

4:32But for example, even in the late 1970s, glyphosate was realized to cause what's known as oxidative stress. Oxidative stress happens when, through normal oxygen metabolism, i.e. we breathe oxygen, we metabolize and make energy from it. As a natural byproduct of this process, we create what are known as reactive oxygen molecules, reactive oxygen species. And these are very reactive, as the name implies, reactive oxygen. They can attack and damage cell structures, molecular structures, including our DNA, our genetics. Now our body has very good mechanisms for neutralizing the excess reactive oxygen molecules that we produce.

5:22But when these protective antioxidant mechanisms get overwhelmed, or say, for example, perhaps you're not eating enough foods that have a good amount of antioxidants in them, you end up in a condition known as oxidative stress, where you have excess, unneutralized reactive oxygen molecules that can then attack and damage cells, molecules. And what's particularly worrying is that it will directly damage our DNA.

5:53Dr Karan: Now, often glyphosate is mentioned in the same breath as GMOs. So what actually is the correlation between genetically modified crops and glyphosate? And why are they discussed together so frequently? Yes, this is an incredibly good question, incredibly important point you've raised here. because what happened was when glyphosate, as I mentioned earlier, glyphosate just kills all plants. So it means you can't spray your crop with it to kill weeds because it will kill your crop as well. So after its launch as a broad spectrum weed killer by Monsanto in 1974, its use kind of was very modest. You sort of cleared weeds from a field and then you planted.

6:36So it didn't actually grow very much. But starting in 1996, Monsanto Company launched genetically modified crops, particularly soybeans and maize, corn, that were genetically engineered with foreign genes, actually genes from bacteria, that made the crop tolerant to glyphosate. So now what the farmer can do is they can spray their crop, they'll kill the weeds, but the crop survives. Very, very convenient, very, very handy. But of course, what happened there that we now know has not been a good thing. Firstly, the environmental impact has been catastrophic in a way. Because you get this sort of intense monocrops growing.

7:22Intense monocrops and any weeds which wildlife would normally feed off. The broader ecosystem. The broader ecosystem impacts have been enormously damaging, enormously negative. So that's one thing. But also the residues of glyphosate herbicide in the foods has gone way, way up.

7:43Dr Karan: I want to pull that thread on this sort of microbiome impact, this shikimate pathway, which these weeds have, which obviously is good for killing weeds. We don't have, which bypasses the human health impacts. But human health, as we understand, is very closely linked to our microbiome health. And so what affects them does have a consequential effect on us. So if glyphosate has a microbiome impact, that's obviously detrimental for us. Is there any high quality human data that we have on the gut microbiome and glyphosate which suggests that? Not human data because we can't conduct a toxicity study in humans because it's unethical and you'll never get approval, rightly, for feeding a potential toxin to a large cohort of people.

8:28That's simply unacceptable. But we do have many laboratory studies. Now, actually, before I go on to describe them, I should raise an important point here. Regulatory agencies, when they set what they consider safe exposure levels of a chemical pollutant, a toxin, they rely on toxicity studies in laboratory animals, especially rats. But it could be others like mice and rabbits, you know, it just depends. So when you conduct a regulatory toxicity study for market approval of your chemical, the way that study is conducted is that you start with a very high dose where you see a clear damaging effect of the chemical.

9:16And then you reduce it, reduce it, reduce it until you find what's known as a no observed adverse effect level where you look at the animals. That's the threshold. That's the threshold. But because an animal, a rabbit or a mouse or a rat are not humans, you have to factor in a safety threshold. And of course, there's huge variation in the human population, which would result in different sensitivities. And so what the regulator does is it takes this no observed adverse effect level dose found in one animal or another in animals and then reduces it by 100. For humans. For humans. And so human extrapolation.

9:55So then it says, right, for humans, this is what we would consider as what's known as an acceptable daily intake.

10:01Dr Karan: Why would they reduce it for humans since we have a greater body mass than animals that have been studied like rabbits or rats or mice? The reasons given are simply that because obviously the biochemistries and the organ structures and functions, there's clear overlap between even a rat and a human. But there are differences. It's just safer to reduce. It's safer to reduce. You can't set it at the same level. You've got to reduce. Plus, as I say, there is huge variation genetically and biochemically in the human population. And some people are bound to be more sensitive. We know you take a group of 100 people and you expose them to the same chemical.

10:40Some will react more acutely than others. So you've got to factor that natural human variation into things as well. So you add another tenfold safety.

10:50Dr Karan: Quick one before we continue, and something I've been genuinely nerding out on in my chief of science role at Throne Science is poop and pee. You see, most of us are completely blind to what's happening in our guts and urinary health day to day. We often wait until something is wrong, but your body's actually constantly churning out data in your urine, in your bowel habits, in those patterns that most people never track. I'm proud to say that at Throne Science, we're building technology that captures exactly that. Passive, consistent biomarker monitoring of your gut health, your hydration status, your prostate health markers, without you even having to think about it.

11:25Dr Karan: From a clinical standpoint, the shift from reactive to continuous monitoring is really important because that is where the early signal detection happens and that's when you can change your habits and hopefully outcomes as well. I've been deeply involved from the science side because I think the research here is serious and with rising rates of colon cancer, poop talk is no laughing matter. So if you're curious about what that data could tell you, the links in the show notes. Do you think, because I know there's a lot of fear around glyphosate by a lot of people, And I think some of that fear has been brought on by the IARC.

11:59Dr Karan: Yes. You know, and they obviously set thing. I think they class glyphosate as a 2A group, 2A carcinogen. Correct. Probably carcinogenic in humans. Yes. That data and that classification was based predominantly on animal studies, you know, in rats and mice. And they base it on hazard versus risk. Right. Yes. And most people, the general lay public, don't understand the difference between hazard and risk. Yes. So do you think there is slightly too much fear mongering for the general public because of the IARC setting, you know, saying possibly carcinogenic or probably carcinogenic, where in actual fact it's about dose and toxicity and exposure?

12:43Dr Karan: For example, water, depending on if it's inhaled, can be dangerous. Depending on if you drink a thousand liters in a day, it can be dangerous and can kill you. Yeah. But just drinking a glass of water is beneficial. Yes, I think the way I can, very good points again, I think the way I can address that is, it's to go back and just mention what is this acceptable daily intake set by regulators based on animal studies for humans. And it is in the European Union and the UK, it's pretty much, is actually lower than the rest of the world and it's half a half a milligram per kilogram body weight per day for glyphosate for glyphosate and so in other words somebody like me i weigh about 60 kilograms according to the regulators i can ingest 30 milligrams of glyphosate day in day out for the whole of my life and i should feel absolutely no adverse health effect from that based on that in other parts of the world these safe limits are actually set higher you know double that.

13:48But going back to the IARC, the International Agency for Research of Cancer, which is a branch of the World Health Organization, you're absolutely right. They based their categorization of glyphosate herbicides, glyphosate herbicides, I'll come back to why I make that distinction in a minute because it's very important, as a group to a probable carcinogens because there was sufficient animal studies of the type we've been describing that shows that glyphosate can cause cancer, albeit at high doses. So it identifies it as a cancer hazard at these high doses. There was good mechanistic evidence.

14:29I mentioned earlier the oxidative stress. The IARC, again, identified very solid evidence that glyphosate can cause oxidative stress and what's known as genotoxicity or DNA damage. These are the most potent risk factors for cancer, oxidative stress and DNA damage, highly recognized. And lastly, they did say that in terms of human epidemiological studies, human surveys that try to link one cancer or other with exposure to glyphosate, they thought that that was equivocal. It was not solid. Now that's changed actually with respect to non-Hodgkin lymphoma. We now actually have several well powered, well executed epidemiological studies that show that occupation, those who use glyphosate as a part of their work, as farmers, groundsmen who spray around school grounds or whatever, there's a very clear connection with use over years.

15:30You know, we're not talking about one week. Cumulative damage. over time and then getting non-Hodgkin lymphoma. So that is the IARC position. These are high risk individuals. These are high risk individuals. Now, where have we come on the cancer story with glyphosate and glyphosate herbicides? Dramatically changed for me last year. A study known as the Global Glyphosate Study led by the Ramazzini Institute in Italy and which my group, it's an international consortium and my group is a part of that. Last year we published a paper, rats were exposed from mid-gestation. Now we started the exposure mid-gestation and then followed the offspring out to two years.

16:19The reason we started exposure mid-gestation of course is because that reflects a more real world exposure. We don't start exposure when we're young adults. We're starting exposure even when we're in the womb and going forward. And in this study, we gave the rats three doses of glyphosate. The lowest was the European Union and UK acceptable daily intake. And the highest was the European Union, UK, no observed adverse effect level dose. And then there was an intermediate one. And then we also fed the animals two different types of commercial glyphosate herbicide formulations. Now, what do I mean by that?

17:03When you, like a gardener, you know, you could go to a garden center and buy a bottle of glyphosate herbicide. But it's not just a solution of glyphosate in water. If you were to make a solution of glyphosate in water and spray on plants, nothing happens. The reason for that is that the glyphosate can't get into the plant. You know, the plant has tough cell walls. And so what the manufacturer has to do is mix in with the glyphosate, so-called co-formulants or adjuvants, that they allow the glyphosate not just to wet the plant, but actually literally punch holes in its cell walls and allows the glyphosate to get in and exert its effect.

17:42Now, it turns out that work from my own group and others going back many years has shown that although regulators on the whole, they ignore the toxicity of the co-formulants in the commercial formulations as used by people in all walks of life are far more toxic than glyphosate alone. They're generally ignored. When a regulator has set the glyphosate safe limit, the acceptable daily intake I mentioned earlier of half a milligram per kilogram body weight per day, it's just on glyphosate. So in this cancer study, we gave the rats glyphosate alone, and then it's the same glyphosate equivalent dose, but as these commercial formulations.

18:27One that's typical of Europe, like here in the UK as well, and the other is typical of the United States. And as I say, the exposure was started mid-gestation, early gestation, and then the animals continued their exposure all the way through to two years. And what we found in that study was that even glyphosate alone, at the lowest dose, the acceptable daily intake, what regulators say, we should see no adverse effect at all. We found a statistically significant increase in numerous types of cancer, particularly leukemia and skin cancer. And some of the cancers we saw, we saw only with the commercial formulations.

19:11but in many of them the glyphosate was just as carcinogenic as the commercial formulations the round the roundup formulations so demonstrating that those types of cancers are actually caused by the cancer by the glyphosate and not by these co-formulants in the mixture so what does that tell us that basically this this study was completely regulatory compliant according to regulatory rules. And therefore what this study tells us is, is that the regulatory set safe limit for glyphosate herbicides is incorrect and that we need to revise it. And we need to revise it downwards, obviously, because even the acceptable daily intake is not a no observed adverse effect level.

19:56Dr Karan: So when regulators, you know, first concluded that glyphosate was safe for widespread use and he also fixed their dosage. They were relying on studies that had been done previously and they looked at the toxicity and they set a certain dose and then they went below it for humans. What were they relying on to set that versus your study, which you try to replicate what they did and you found significant discrepancies and an even lower safety threshold. What was the differences there? Like why was there that discrepancy? I think we, in the earlier studies, much higher, only much higher doses of glyphosate and different experiment, there were different experimental setups.

20:36I think our study under the global glyphosate study umbrella of investigations, what we did for the first time was to actually test the regulatory permitted doses over a two year period in these rats, which is what again, regulators say, minimally you should look for these kinds of cancer, carcinogenicity cancer studies. And that hadn't been done before, but this is a situation we're faced with now. Basically based on our latest study, what we can say at the moment is, is that actually the safe dose of glyphosate is currently unknown. Even based on your study? Yeah, because even the lowest dose we tested, which is the acceptable daily, regulatory acceptable daily intake, still caused cancer in these animals.

21:23So, what needs to happen of course is that the study needs to be repeated where you go down even lower to try and establish this no observed adverse effect level.

21:34Dr Karan: Are there going to be more studies done do you think to continue to establish that no observed level at a lower dose? Well, it's certainly needed. Whether that will be done or not, I'm not sure, but it's certainly needed and that we We obviously hope that both at European Union, but also UK level, glyphosate market approval is under reassessment as we speak. So we hope that the health and safety executive, which has been entrusted with the task of assessing glyphosate safety and whether to approve it or not in an unrestricted way or in a restricted way. And you think we should, in those future studies that need to be done, not only do we need to titrate the dose even lower to look at that, but we should also be testing glyphosate with these coformulants at the lower dosing.

22:22Dr Karan: Both of them need to happen in parallel. Brilliant. Absolutely right. And this is again where regulators have for me been negligent in this respect. They have ignored the toxicity of the coformulants in the commercial formulations. What are these coformulants? Are they sort of ethanol based? Are they acids? What are they? Organic acids? We know what some of them are, but in many cases, the industry doesn't declare them on the packaging. It's a trade secret. Okay. That's quite dangerous. It is very dangerous not to know what's there. When we wanted to know what's been in one, we've had to do our own mass spectroscopy analysis to try to identify what's been in there.

22:56Dr Karan: Why isn't there any regulation that you have to declare what chemicals are ultimately being consumed in small quantities by humans? Absolutely. It's a mystery for us why regulators don't demand this. The industry has declared these coformulants as, quote, inert, unquote, because they don't directly act as a herbicide. But in terms of toxicity, the evidence is overwhelming, not just, as I say, from my own group, both in cell experiments in the laboratory, but also more crucially in rats, in rat toxicity studies. We have shown consistently that the commercial formulations always come out as more toxic than glyphosate alone.

23:41Glyphosate alone can be toxic, but the coformulants added to the glyphosate in commercial formulations come out way far more toxic. I think it's absolutely.

23:50Dr Karan: So, you know, when it comes to glyphosate, I know there are people out there who are fearmongering people about glyphosate and are completely saying we need to get rid of them. I understand people's concerns. I'm also a scientist and I understand the need for new ones and the need for pesticides to protect crops. I understand all of that. And if people are doing the proper testing on glyphosate, which your group are and regulators are, and we can establish, you know, the dosing and the cumulative damage, I think that's fine and continue to do that. As long as there is transparency in the ingredients used and people know what is in the food chain and ultimately what is the exposure that we're seeing, even if it's on a low level, you know, I don't want to fear monger on that.

24:30Dr Karan: I think it seems to me strange and almost slightly unacceptable that there wouldn't be a disclosure about what is used in the co-formulants and adjuvants that are added to the glyphosate, because then how can you adequately trace and test what is being used? Because then, you know, the IARC puts glyphosate as a 2A carcinogen based on the animal studies, but also what else is in the mix that needs to be tested? Because then you cannot do an appropriate robust testing with the black box. What you say is absolutely correct. And to this day, it's a regulatory oversight that the co-formulants, not just with glyphosate herbicides, by the way, all pesticides are marketed as part of a formulation with additional additives in the mix to enhance the effect of the so-called active ingredient.

25:26And almost invariably, the commercial formulations come out more toxic than just the active principle on its own.

25:34Dr Karan: You mentioned that you've been seeing some gut microbiome impacts of glyphosate. Have there been any human preclinical studies done where you used human fecal microbiome samples and tested the impact of glyphosate on human microbiome samples? And if so, what specifically are we seeing in terms of the negative impact on the gut microbiome? Yeah, the more definitive work on the effects on gut microbiome are from the animal studies, where you look at the effects on the whole organism. Yes, there has been work where we've taken, including one study from my own group, where we took the gut content or fecal samples, extract the bacteria, grow them in the laboratory, and then administer the glyphosate and the commercial formulation.

26:21We did see changes in metabolism when we did that, but the glyphosate alone didn't do much, but the commercial formulation was the one that showed the disturbances. But of course the effects on the whole were not very dramatic. But I think for me, the reason for that was, we got some useful, interesting information, but it's out of the body context. What goes on in the whole body is obviously the influences are far greater than what you can mimic in growing the bacteria in the body, which is why the definitive work has come from laboratory animals, especially rats, where we see, again, depending on the design of the experiment, Any changes you see with the commercial Roundup formulations, you see more dramatic effects than glyphosate alone.

27:10But interestingly, our first venture in this area gave us some rather interesting results. We didn't see much of a disturbance in the populations of the gut bacteria. Just the functional changes. The functional changes were very dramatic. And what most worrying amongst those was that we saw clear evidence of oxidative stress again in the gut being caused by the glyphosate alone at the higher doses, but also the European commercial formulation.

27:38Dr Karan: I want to talk about something that's quite personal to me and about some medical conditions that I suffered from. I used to have high cholesterol and fatty liver disease, and that primarily stemmed from a severe lack of fiber in my diet. And on my quest for finding the perfect fiber supplement over the last few years that could help me add more fiber into my diet, I couldn't find one. That ticked all the boxes that I wanted and the high bar that I set for myself. So I built Loam Science. What I'm most proud of is not the product. I know that's great, but it's the fact that we've run two clinical trials on it, two randomized controlled trials, which is far more than the vast majority of supplements on the market will ever do.

28:13Dr Karan: And we've got even more coming because I'm a doctor first and foremost and a scientist, and I wanted to build something that I could actually stand behind with data and not just rely on good branding. So if you want to understand what's inside Loam Science and why, The science is all on the website and the link is in the show notes. Are there any specific foods which carry more or lower levels of glyphosate exposure? I mean, apart from the sort of soybean and wheat that you've mentioned or the corn that you mentioned? Yeah, we don't have to worry too much about that here unless you're buying foods made from imported corn and soy.

28:45From the US or South America. The main worry from exposure here in the UK to glyphosate are actually cereal products. Wheat, oats, barley, rye. The reason for this is that several decades ago now, beginning at least in the early 1980s, farmers began, no doubt from industry encouragement, they began to undertake a practice which became known as pre-harvest desiccation. So what they do is within a few days usually of when they want to harvest their wheat or their oats, they spray their crop with glyphosate herbicide Roundup and intentionally kill it. And supposedly what that does is it results in more uniform dryness of the grain and they can harvest sooner and get to market sooner.

29:34So it's very convenient for the farmer. But of course, what that results in is residues of glyphosate herbicide in the grain. So it ends up in bread, breakfast cereals and so on and so forth. And so has that been conducted that indeed, you know, a high percentage of the breakfast cereal, oats, especially oat-based, but also wheat-based bread, you analyze those and you find glyphosate residue.

30:00Dr Karan: You mentioned before that there's an effect on obviously the absorption of metals, especially nutritional metals, manganese, magnesium, et cetera. Is there, have you seen any evidence of risk to soil quality and a reduction in soil quality since glyphosate usage has gone up over the last few decades? and then has that impacted soil quality? So the nutritional quality of soil has gone down, which then means the secondary effect is the crops that we're growing are less nutritionally complete than decades ago. Does that mechanistically hold true? It's a complicated, the situation is complicated because it's not just glyphosate that's obviously been sprayed on crops, but there are many different pesticides that are sprayed by farmers on crops before, during, and even during storage.

30:57Grains, for example, can be sprayed with fungicide to preserve them better. So it's difficult to single out glyphosate as a contributor to the decline in soil quality. We know there's been a decline in soil quality, but that could be no doubt for multiple reasons, including the use of artificial fertilizers. I know also negatively impacts the the soil. But no doubt the impact on the soil microbiome now, the microbiota in the soil, we know this is the health at that level is absolutely vital because the roots of the plant are in symbiotic relationship with the soil microbiota, the so-called rhizosphere.

31:42And that if you disturb that, and I would love to see a study actually to see just how glyphosate herbicides impact that soil microbiome. Whether that symbiotic relationship is compromised. Because if it is, the health of the plant is compromised and the quality of the food is compromised down the line as well.

32:04Dr Karan: How, you know, obviously we're exposed to glyphosate depending on which part of the world we live in and, you know, what we consume as well. How quickly does our body just process and excrete and metabolize glyphosate? Glyphosate is actually excreted quite quickly. It's kind of like water soluble. It doesn't accumulate that much in different tissues of the body, except for bone, maybe because it binds to the calcium there. I mean, that's a reasonable hypothesis, I think. So it is excreted quite rapidly. But the worry of course, is that you're topping up on a daily basis. If you're eating the same types of foods, contaminated foods on a daily basis or using it regularly, if you're using it occupationally especially, then there is a cumulative impact on your physiology, which I think is what we've seen with the cases of the link between glyphosate herbicide use and non-Hodgkin lymphoma.

33:06You may be aware of the over 160 ,000 court cases have been brought litigation against Bayer Monsanto, the makers of Roundup herbicide, because these are people who used over many years Roundup glyphosate herbicides, and they came down with non-Hodgkin lymphoma, very serious cancer, as you can imagine. And they're linking that to their year's use of these herbicides. and many of these so so far it's cost bay and monsanto millions of dollars in payouts and there's still over 60 000 left for them to sort of deal with what that illustrates is that it's not just one exposure but it's the cumulative effect over time if you're eating it or using it over occupationally which is where you're going to get not just by ingestion through food but it'll absorb through your skin and you inhale it very readily.

34:03Dr Karan: I think, you know, I guess the thing I'm trying to contest with is clearly based on everything you've said, we need a lot more ongoing longitudinal data, testing, transparency over what is being used and looking at more epidemiological human cohorts as well, which is obviously being, you know, hindered for whatever reason. People don't want to spend the money to do these studies because it's not in their best interest. It's been around for decades. So maybe people think, what else is it going to show us? But, you know, I think all of these things, as we continue to understand the role of the microbiome, I would like to see personally more maybe human preclinical studies on the impact of the microbiome and pairing that with some observational human data as well.

34:47Dr Karan: Difficult to do, you know, RCTs ethically, as you rightly pointed out. But yeah, I think definitely, yeah, more human data is required. And, you know, I just want to thank you for joining me to at least pioneer some of this research out there. And I know you're working with a lot of PhD students who are looking at other environmental toxins, looking at the impact of human health. So thank you so much. Yeah, maybe I can finish on this point, Karen, if I may. First, it's been a pleasure talking to you this but I think what I would always like to try to do is let's place glyphosate in the bigger picture of pesticide use for me you know glyphosate has always been touted as the safest pesticide of any type that's ever been invented but what we're finding is for me glyphosate has turned out to be deceptively toxic because it takes time, long-term exposure for it to show its effects, even at very, very low doses.

35:49One study I didn't mention earlier is that in one rat study that we conducted, we fed the rats at what I called an ultra-low dose of Roundup herbicide, glyphosate herbicide. That was on current levels 125 ,000 times below the current acceptable daily intake for glyphosate. And yet our rats, after two years exposure, came down with non-alcoholic fatty liver disease. Now, this is what I mean by it's deceptively toxic given it took two years for this liver disease to be seen in the rats. It's took years for people to come down with non-Hodgkin lymphoma in the United States. So it reminded me of things like DDT, you know, those organic chlorine insecticides invented in the fifties that were supposed to be so inert to us that they were being sprayed all over the place.

36:42And yet their negative impacts manifested eventually and they were banned. So when you place glyphosate and if glyphosate is supposedly the safest pesticide are invented, what about everything else? And I think the conclusion that you arrive at is we've got to move in the direction of an agricultural change, fundamental change in agricultural practice to an agroecological pesticide free. Because at the end of the day, there's only one safe dose of a cocktail. You alluded earlier to the only survey of the UK population for pesticide residues in their urine was conducted by my group. working with Tim Spector's group over at St.

37:28Thomas' Hospital. And we had about 160, 170 subjects. Not bad for this kind, the number's small on one level, but actually for epidemiological studies or human surveys, that's not a bad number. We found that 53 % of the urine samples we analyzed from these people were positive for glyphosate. Interesting. But 100 % of those urine samples was positive for organophosphate and pyrethroid insecticides. showing us that actually people generally, these were not special people living all over the UK, are exposed to a cocktail of pesticides every day and that the health consequences of this cocktail is currently being ignored by regulators.

38:13But based on the animal studies we've done of pesticide mixtures, we fear that these indicate that there will be long-term health consequences to being exposed to these cocktails of pesticides. So we need to, I think for me, we need to move away from these chemicals to a much more environmentally and safer human from a human health perspective of farming practice system.

38:41Dr Karan: I think absolutely. I think, Alish, it should trigger more research and more innovation, at least in this area. And Professor, thank you so much. Been a pleasure. Thank you very much. Thank you.