 Yn y gweithio'n hoffi, mae'n rhoi'n gallu'n sgwpeth yn y gweithio'n hoffi yma. Mae'n hoffi ar y ddiweddol yn y ddiddordeb sydd yn cyfrifio gwir, yn y ddiddordeb yn Y Ugan. Mae'r problemau ar y ddechrau sydd wedi gweld ffawr o ddysunfektion o hyd o ddysunffektio ar y ddysunfektion ar y ddysunfektion sydd yn ddysunfektio ar hyn mawr. The solution was to train some of the staff working at the plant to field trial a testing kit, and the benefits from this, of course, were to ascertain the safety of the water being supplies, but also to develop some thinking around recommendations for the future or indeed the approach to be taken to this specific issue in the future. So the context just briefly goes through. Some of you, of course, will be aware of the intervention or certainly aware of the refugee crisis, refugees from South Sudan coming into northern Uganda and some of the largest refugee camps in the world in the area. We, as MSFOCA, responded in Pallorina settlement, as the camp is called, at the beginning of 2017, due to there was an existing settlement there, but there was a massive influx of people over the course of a few weeks, tens of thousands of people. You can see some of the scenes here when people arrived, and this is where we're talking about. And fortunately, in some senses, the site was reasonably close to part of the river Nile, which you can see in this reproduction of Google Earth image. Our activities, including medical activities, but the biggest gap initially, of course, was the basics. That is food and water. And so we started a surface water treatment project here in this location on the Nile, and the water would be trucked into the camp from there. All the trucks being contracted by UNHCR and Lutheran Well Federation. So this gives a bit of an idea of what it looked like at the time. Significant in terms of the water quality issue that I'm talking about here is that there was a very marshy area upstream from the river. Good in one sense because this gave some filtration to the water, but it also added a lot of natural organic matter to the water. So there was a very phased approach to the intervention. We started initially just pumping and chlorinating the water directly from the river into the trucks. We had, when we first arrived, no equipment to set anything up. It quickly arrived, but that's how it started. Luckily, the river water was relatively clear or clear enough so that we could directly chlorinate. But then in the second phase, we set up a more temporary, sorry, somewhat more permanent treatment system and then moved on to what we handed over in the end to the Red Cross. And this included laboratory within the water treatment plant. We were monitoring both the raw water quality and the treated water quality for a number of parameters. Part of that was monitoring the treatment process itself, which involved the addition of chemical coagulants, then flocculation, sedimentation, and of course disinfection with chlorine as is the standard in this kind of intervention. So water quality monitoring also included within the camp itself as well. So we have a comprehensive suite of data on everything that we sent into the camp. So disinfection byproducts. What are they? I mean it's a big, big subject. It's a big subject of interest and some concern within the water supply sector in every country. Particularly for surface water treatment plants. What we are most concerned about or what we were most concerned about was products called, byproducts called trihalomethanes. And there's just a kind of generic representation there of what those are. And they are formed by the addition of disinfectants and we use chlorine but there are also trihalomethanes produced with the addition of other disinfectants as well. We know some basic facts about those that the production of those byproducts increases with the chlorine dose, increases with the amount of natural organic matter, and then also with temperature, contact time, and with pH. So the health concerns of trihalomethanes is quite obviously there's a lot of literature on this. Like I said it has been, it is a concern in most water treatment operations. The thing for us in the humanitarian sector, it's not something that is looked into in much detail. Part of that is because, and especially for us as MSF, we feel like we're intervening in an emergency. There are priorities in an emergency which go beyond what we might see or what we might determine as risks after extended exposure. So we are talking about trihalomethanes being associated in epidemiological studies with a risk of bladder cancer over extended exposure. And there are considered to be some minor effects from high trihalomethane exposure during pregnancy as well. With respect to fetal growth, there's other outcomes, there's a lot of literature, there's a lot of argument and counter arguments, and there's nothing in any of this that is that conclusive. But it does lead most regulatory bodies national or otherwise to set guideline values and represent here WHO guideline which sets one for 300 parts per billion for chloroform. So that just gives a very brief overview. This reference is there to many studies. So in terms of what we were doing for the water supply, of course as per standard we want to ensure that there is residual chlorine at the tap stand when people come to take the water. Chlorine decays over time in water and because of the nature of the water treatment, the nature of the water that we were using there, we need to set a higher target at the surface water treatment plant. To ensure that by the time the population takes the water that is still the required residual amount at the household level up to 24 hours later. So this is why we were doing a comprehensive range of monitoring at the plant and in the camp. And based on that we were able to adjust at the plant what we wanted to see go into the trucks. So we had a target of 1.5 milligrams per litre of free residual chlorine and out of this represents the results from 322 samples. We didn't do too badly at all and then also in terms of the target at the tap stands it was also not bad considering the quality of the water. The fact that some truck drivers would take the water the night before, sit in the market, not deliver it until the next day, you can imagine. Water trucking is far from an ideal means of delivering water to people. So this had an influence obviously like I said on the production of trihalomethane. It's a reasonably high level of free residual chlorine. So, yeah. And what we decided to do in terms of quantifying better what we might be seeing in terms of disinfection byproducts, we searched around for the appropriate equipment, came across this equipment here produced by HAC which we also found had a good correlation with some of the standard methods that are used in laboratories around the world. It had also we found literature where it had been used as a method in a Bulgarian surface water treatment plant and also in the US in Arkansas as well. What do we find in terms of results? It was not the simplest piece of lab equipment to use but we managed to train the staff to use it well. We found and the results of what we, most of the tests are here, we found that with the standard treatment method that we were doing, which was splitting the sedimentation and the disinfection that we were compliant with below the 300 parts per billion set by the WHO. And even, it's a long story to go into it but earlier on in the intervention we had a different means of treatment which was combining some of the processes and that's where there were likely to be higher risks even then we were compliant with WHO standards. So, what were the lessons learnt? Well, top one I've already mentioned. We know that emergency treatment methods are likely to present more of a risk and that we should move to standard water treatment processes as soon as possible. That part is obvious really. But beyond that we know as well from the literature research that was done into it that this is a fantastically complicated problem. There are many disinfection byproducts and not all of them, there's a few trihalomethanes but beyond that there's many more. So, in terms of recommendations for the future, the first one I have to make and that is that regardless of whatever risks there might be perceived in what is done, the quantity of water provided to people is the most important thing above anything else. But of course working on the quality should come as soon as possible and I think that's what we were trying to do here. We were trying to push that as soon as possible closer to get into those things as quickly as possible. I think and the recommendation that comes from this is that we should be monitoring these disinfection byproducts at these parts that we're running. And we should investigate as well alternative treatment methods which might mitigate the risk of their production. And the last point also is something that we found doing these quite large scale surface water treatment parts in several interventions is that we must always assume that these parts are going to be running for a long time into the future and we know that that will be the case in Palerina. That's great timing. Thank you very much. Spot on.