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So a very warm welcome to Professor Janet Rachel and thank you very much for being our first keynote speaker at the share conference today. Um Professor Rachel is the college Director of Research at the College of Health and Science University of Lincoln in the UK. Professor Rachelle's research focuses on the biological effects of environmental contaminants at the molecular level known as molecular ecotoxicology. Funded projects include microplastics in the air and within human tissues, cancer in fish, endocrine disruption in bivalves, inland waterways, sediment characterization of eu watch list, chemicals and pharmaceuticals in the Humber Estuary. And over to you um Professor Rel, thank you very much for joining us today. Thank you Heather for the introduction and thank you to the organizers as well for inviting me to come and give the talk today. So I usually talk to environmental scientists. Um So you're quite a different audience for me. Uh But you'll see from my research that I veered quite dramatically into health research as well. So before I start, I want to thank all of my collaborators and coauthors, I haven't done any of this work on my own. I completed it as part of a very large team. So and in particular, many undergraduate and postgraduate students, too many to mention that have been involved in all of this work. So thank you to all my colleagues and let's see if I can move to the first slide. Yes. OK. So I thought I would start with an introduction around plastics and their use in health care. And I've used uh Chantal's fantastic publication last year as a way to set the scene from the perspective of health care environments, healthcare settings. So in her study with her coauthors, they've already looked at plastic use that's being used in healthcare settings. And in particular, their focus was to look at the carbon footprint and ways in which they might be able to achieve carbon net zero in the health care setting. They looked at the five most common operations and identified the five biggest contributors and they found that from these products, they were actually responsible for more than 80% of the carbon footprint. So that was helping to move that field along. Um In quite a large leap, the products were things like single use hand drape, surgical gowns, bone cement mix, single use clip appliers and table drapes, things that I'm sure you're common with. Um But I don't usually see in the environmental sciences, the sorts of plastics that were associated with these in terms of their chemical characteristics, their polymer type, if you like were polyester, um polymethacrylate um and polyethylene terephthalate. So these are the types of plastics that you see in textiles, um not just in the healthcare setting, but in all textiles, um perhaps in different types of packaging, like bottles and bubble wrap. So there was a suggestion that switching from single use to reusable plastic where feasible would help to reduce the carbon footprint by one third. And I think this is a, is a really strong conclusion to arrive at. But what I wanted to do today was to ask a few questions. Um The first was would replacing the single use plastic items with reusable plastic be the answer in terms of wider questions. So it might tackle carbon footprint. But are there any other considerations that we need to think about? And also what might those other associated factors or hazards involved in the use of plastic, whether they're single use or reusable plastic that we need to consider? So, what I'm going to do today is to sort of explore these questions through the lens of our recent microplastics research and share some of that with you. So a quick definition of microplastics, um what are they to be honest? Um Even the people working in this research field can't agree. Um We're using all sorts of different methods to characterize them. Some people rely just on shape and color others, move on to chemical characterization techniques, but even then we can't agree on one true technique. If you like, and there are probably about four or five that people are using. It means that there are no standardized or harmonized methods for measuring them. Um And that can sometimes bring into um uh it's confusing as to whether you can trust the datasets or not. For today's talk, I'm going to use the classification of between one microm at the smallest size range and two millimeters at the top of the size range. So at the top there, if you think of a sesame seed, that's the largest piece of microplastics that I'm going to be talking about. There's also some disagreements about um in terms of the robustness, how um how reliable is the data and this comes down to things like procedural controls and the use of reference materials and these sorts of things. I'm not gonna get too bogged down in this today, but I do want you to be aware that there is some debate in the microplastics research field. So pressed the wrong forward button. So I wanted to say how I got into the er field of microplastics research. Um I am actually an environmental toxicologist and I started looking at microplastics in muscles, not the kind in your body, but the ones that we eat and scallops and fish. And these were from the point of view of microplastics out in the environment and to what extent they might be in our food chain and to be able to do that we use this method um called F tr Fournier transfer infrared spectroscopy. Now, I'm a biologist, I'm not an analytical chemist. So I very much use this as an analytical tool. Um in very simple terms, you place a particle um the laser goes through that particle and then you get a spectra and you use that um the spectrum to compare it to a library of those. And then you look for a match to a library of different chemical polymers. We use a 70% match threshold. So if a piece of plastic has been out in the environment or indeed in somebody's body for several decades, it won't look anything like the virgin polymers that you have in these libraries. So we have to have some flexibility in trying to work out what these polymers are. So we, we began our work looking in fish and muscles and to cut a long story short, we found uh microplastics in all the muscles, whether they came from out in the field and the environment or whether they came from your supermarket, they all have microplastics in them. Fish was a slightly different story. We found them in the gut, the gills. Um and that was mainly where you found a knot in the flesh. So that was where we started this research. We then went on to do some um systematic reviews uh to work out how much was in other types of foodstuffs. Um It's slightly depressing news, I guess in that you find, um, microplastics pretty much in most food products. We looked at salt, um, seafood and drinking water and in particular drinking water, whether they're from, um, within plastic bottles, um, or whether they come from the tap and you do see a lot of variation in the levels that we found. But the take home message is that we have microplastics very much within our diet, whether that's food or whether it's drinking water moving on from that, we then thought about microplastics in the air. And we carried out a study in um 20 homes throughout the city of Hull and East Riding. And you can see some of the data um in the sort of candy chart on the right. And you find that in people's homes, you do find microplastics in the dust that accumulates in your living room. So were very technical. 1 L jars just used to collect the dust at head height in people's living rooms. We found lots of different types of plastics. Um So on the bottom graph there, you can see different types. You've got polyester, acrylic, polypropylene, polyethylene, terephthalate. Again, lots of fibers and a variation across the seasons as well. So by this time, we'd established that m microplastics are also in the airborne environment, both in our homes and outside in the environment around us as well. We then thought, so what do we really need to worry about this? And this is where we started to look at work around um human tissues and the the sorts of routes of exposure we're thinking of here. So we know they're in the food and the water, we know they're in the air. So we were thinking about three routes of exposure. Um initially inhalation and diet and later we came to operations as well. The methodologies, I just want to mention that caveat again in that it's difficult to measure microplastics because they're everywhere, they contaminate everything. So you do need very strict q procedures. And if anybody wants to ask me about those questions, I'll be happy to explain those. But from our own work, we started with tissues um supplied by clinicians um at Hill Hospital. So we had lung tissue, initially, vein tissue, um some samples of urine and then we've gone on to look at um some procedures in the operating theater including bypass. Um And I'm also going to talk a bit about some future work that we're doing as well. So I'm going to give you a quick whistle top tour of what we found in terms of microplastics in human tissues. So, first of all, um looking at the lung work, so here the surgeons um supplied us with um 13 pieces of tissue from 11 patients undergoing surgery. So there is a caveat already that these um people are actually already ill. Um And uh in looking at those samples, um we divided the lung into three areas. And again, to cut a long story short, we found microplastics in each part of the lung. And you can see here a graph of how many total microplastics were identified from the upper, mid and lower parts of the lung. I think most surprising for us and particularly the respiratory biomedical scientist, my coauthor Laura Sadovsky was that they were in the bottom um the lower part of the lung. Now, why would we would we would be surprised at this. Well, remember the microplastics size range is a micron which is, you know, already not in the manner range. It's just reaching that but all the way up to two millimeters. And we did find fibers that were as much as two millimeters long in the lung tissue. On average, there was um perhaps aplastic per gram of tissue in those samples and the types of plastics oops have gone press the forward button. The types of plas plastics that we found were uh sorry um polypropylene, polyethylene, polyethylene, terephthalate again. So things that come from packaging from bottles, um things that might be in clothing as well. These kind of textile fibers also um we wondered about are there other chemicals associated with these microplastics? And we did actually find a PS type chemical um PTF E uh which is actually um used in Teflon, the Nonstick um chemical that you use to co uh cookware, for example. So there were also plastic associated chemicals found here as well moving rapidly on to some other tissues. So these are vein tissues um from people undergoing a heart bypass surgery. Again, we also found microplastics in these tissues from our five samples. Um four of the people, four of the patients have microplastics in those tissues. Um One of the things we noticed here though was that in the blanks in the procedural blanks, we have very high contamination. And this started to make us wonder about where's all that contamination coming in terms of the air, the the environment in an operating theater. Um So that was also another finding of this work. Um The types of microplastics again are kind of interesting, they were mainly fragments this time instead of fibers and they are about 120 microns and 40 microns in size. And again, we also found some microplastics associated chemicals in these samples as well. Moving on to um some other uh questions we wanted to know whether an any of these microplastics in your gut or your lungs could be taken up into the blood and also whether they're excreted. So in terms of the blood, there's already a study published by Dutch colleagues on human blood where they took again about 20 I think it's 24 donors. They used a different technique which is called um or on gas pyrolysis. And they found microplastics in a majority of those samples. However, using that technique, you can only really say whether a certain number. So they were looking at a specified range of polymer types, which were about five different polymer types. So we repeated this study with another 20 healthy donors. And we were able to look not just at whether microplastics polymers were present in this range of polymer type, but we could expand that out to see what the whole range of polymer types might be. And also what the size and the shape of these particles are. So, we've added a bit of data here in terms of there are 24 different polymers that we've identified. And we've also worked out the sort of size and the shape and again, the average shape is around 100 microns which does seem rather large and they tend to be fragments and then looking at urine samples, these presented different um types of um what shall we say, challenges in that um collecting urine samples was either from a clinic. Um So these are from uh women who have endometriosis um uh problems and um they're either donating in a clinic or in their own home if they're the healthy don. And one of the problems is that um body fluff if you like gets in the way of this analysis. So we all have body fluff um in our nooks and crannies and typically, it's from the clothes that we wear and these are textiles and they're often from um polyester type fabrics or ray on these kinds of things. So, um working with uh the urine samples was challenging. Um but we were able to also get some urine samples via catheter. And as soon as you think of catheters, you're probably thinking plastic catheters. But actually on this instance, um they did use metal catheters and the take home message here was that we found microplastics in the urine samples. There were more in the um the ladies with the endometriosis type condition. However, it wasn't a statistically significant difference that we found. Um but they were of a different size and there were different polymer types. Um Again, the size ranges were kind of surprises surprising in that we found um an average size of around again, 100 microns in terms of um fragments. And this for me um was very baffling because I'm wondering how they've come through a kidney which you know, there there is, I would presume about 1000 to 10, 10,000 times too large to come through that organ. Um Maybe they've come through blood vessels directly to the bladder. We we discussed that in our manuscript. So moving on in terms of the, so what so the plastics are present? Um why should we worry about this and where am I going in terms of this talk? So we did do a meta analysis of the effect of microplastics in toxicity studies. And there are these toxicity studies have used 10 different polymer types, 15 different cell models and three different shapes. And what the outcome of that systematic review showed was that yes. Um in these cell based type assays, there are significant impacts in terms of cell death cytotoxicity. Also in terms of immune response, um characteristics, oxidative stress indicators and also barrier integrity problems as well to date. There's been no examples of genotoxicity. However, but the m the I guess the message here is that yes, microplastics are toxic in a cell based type assay exposure also in um rodent model type toxicity tests. But there's a very big however, and however, here is that these studies have all tended to use microplastics spheres. And so far, I haven't mentioned microplastics spheres because we have found zero in any of the human tissues that we've examined. So what we really need is for these people to go back and do all of these cell toxicity studies and animal model studies again. But this time with fibers and fragments so that they're more environmentally realistic. I've also not really mentioned too much about the leachate from plastics. So if you can imagine these floating around in a body or out in the environment, they also contain as many as 20,000 different plastic additive chemicals. And we know that approximately 4000 of those are known to be toxic. So some of them are carcinogens, some of them are endocrine disrupting chemicals. Um the plastic companies don't have to tell us what's in their plastics. Um, and that would be quite a good thing for them perhaps to do in the future. So these are things like, um, the, the Forever Chemicals, pfos, pfos and also bis phenols as well. And phthalates are another group. So that's the, so what, why would we be, um, particularly concerned about microplastics in surgical procedures? So, as a result of the work on the um the vein work where I mentioned that we were wondering why there are so many in terms of the background contamination. We did start to think about procedures. And could they be introducing microplastics is the single use bubble wrap producing microplastics in the air in the operating theater environment. So we carried out another set of experiments this time using different um bypass machines. Um So people weren't hooked up to these at the time, they were isolated, but we ran them in a kind of mock operation format. So we used a conventional style and we also used a mini style of circuit. And what we found was that after running them for three hours, you found small pieces of microplastics, polymer particles in all of the buffer that have been circulating for these three hours. Um different types of plastic to those I've mentioned in the human body, but some of them are also similar. So we still see polyethylene but now we're also looking, we've got some PDMS and PBMs. So different types, almost certainly from, um, the types of materials that are using to make these different types of machine. The sizes again are around about 90 microns by 30 microns. Um And we also found some of these pfas for forever chemicals as well and they tended to be fragments and fibers. We didn't find any spheres then looking at the room in particular as well. Um We carried out another series of experiments um again, using the one that we used in people's indoor living rooms and we worked out how much was in the dust in um an operating theater and also in the, the nearby anesthetic room as well. And we found that actually relative to our living rooms, there are a very high number of microplastics floating around in the air in an operating theater. Um During the non working hours, we didn't detect any. So it's definitely associated with the operations. We found fragments and fibers and again, no spheres, the types of polymers, polyethylene, terephthalate, polypropylene nylon, and some of these associated pfas chemicals as well. So, what I want to do now at this point is to circle back to the original question and plastic use and sustainability in health care. And I want to think about the single use versus the reusable use items. Now, and I'm going to talk a little bit about some funding that we've recently been awarded, which is very exciting with new coauthors as well. So in this rose trees funded project with Chantelle uh Mood Mahmood at Castle Hill and Rob Bennett and also at Castle Hill and Simon. Um at the University of Hull, we have some funding to look at microplastics as um an emerging sort of threat if you like in a healthcare setting. And this project will look at the sources of the plastic and try to actually match the polymer types of the fragments we're finding in the air to the actual implements if you like or the single use implements that we're using in these practices. Um We're gonna look at common devices such as airway devices, fluid bags, cannula. And we're also going to try to see if they're shedding microplastics in a kind of buffered um constant um use type of exposure as well. So we'll characterize them in terms of the levels that they might shed the polymer types and the sizes and the shapes because remember, the shape is quite important in terms of perhaps immune response and oxidative stress. A particularly fun part of this project is going to be to carry out some mock operations. Uh in the first, um we will use single use type items and then in the next set of operations, we're going to use replacements and we'll be measuring the levels of different types of microplastics in the air during the course of those. And then we also aim to disseminate these findings to inform practice, hopefully and also policy making decisions too. So some quick examples that I thought of here, um, reusable sterile curtains. Um, these are actually the reusable ones are also PVC coated polyester. So I'm wondering if this is actually an improvement on a single use type of um, curtain. Another example are reusable airway devices. And I just wonder here, will they share more microplastics after each use or will they not, um, also will they leach any associated chemicals? Remember I said there are about 20,000 different plastic additive chemicals potentially in some of these products and in terms of reusable drapes, these are some of these are 50% cotton, but some of them are 50% polyester. And I just want to wonder out out loud, are these actually an improvement on single use or not? But hopefully, our mock operations where we um switch some of these in for the single use will give us that answer. So in summary, microplastics are everywhere. I'm afraid slightly depressing. Perhaps they're in the air that we breathe, they're in the food um and water that we drink. Um They're definitely taken up into human tissues. Um There's also evidence suggests that they're traveling around our body. Um they represent also an accumulating pool of potentially toxic leachate from these associated chemicals. Now, if you think of the people that are in these operating theater environments have already said that the air contains very high levels of microplastics relative to somebody's living room, for example, or even outdoors. And is that something that um patients and healthcare professionals would want to be aware of? I'm sure they would. Um That's something I think that we need to think about and hopefully that we will be able to provide some answers and mitigations in terms of single use plastics and reusable plastics in the future. So that's everything from me. Uh Thank you very much for listening and again, a huge thank you to all of the coinvestigator coauthors.