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Bacteria At The Water Fountain: How San Diego Scientists Use E. Coli To Test For Toxins In Water

 February 18, 2020 at 10:15 AM PST

Speaker 1: 00:00 It's not always easy to tell if the water you're drinking is safe, but ways to check include lab testing and filters and interestingly E coli bacteria, KPBS science and technology reporters, Shalina Chut Lani spoke to San Diego scientists behind a new bacteria based water sensing technology. Speaker 2: 00:21 It's lunchtime at San Diego's Edison elementary school on a December afternoon and the kids are excited. It's well known that what children consume here will impact them from the teriyaki chicken to the drinking water at the nearby fountain. Even small amounts of contamination and water like mud can permanently damage a child's brain and body. Speaker 3: 00:44 You don't have to look very far to find Flint, Michigan and see what high levels of lead in the drinking water did to the people who live there. Speaker 1: 00:51 Sam or Naji is a facilities manager with the San Diego unified school district. He's referring to a water crisis in Flint, Michigan. That began in 2014 when thousands of school children and residents were exposed to lead and other toxins in the city's water system. It was a wake up call for cities and school districts nationwide, including San Diego unified. Speaker 3: 01:12 We quickly asked the city of San Diego to come and pull up to five samples of water from every single district school. Most of our sample results were okay, but you know, working with parents we really wanted to do better. Speaker 1: 01:23 Since 2017 the district has tested thousands of water fountains and taps. It also reports levels of lead well below what the government requires, but Naji says it's hard to monitor lead and other heavy metals continuously. Speaker 3: 01:36 Our testing protocols are incredibly strict and that that's time consuming, right to to secure the water fountains for a night to test the next day, to send it to the laboratory, allow that laboratory to conduct their analysis and send back results Speaker 1: 01:48 so contamination may not be detected as it's happening. The problem is larger tests can be expensive and time consuming and cheaper tests may only be able to detect a few contaminants at one time. This situation is an issue for any water system where people and children can be exposed to toxins. That's why San Diego researchers look for a solution at a UC San Diego lab. Bioengineer Lizzie's to shell ski opens up the machine, right? Speaker 2: 02:15 So this is the singer instrument that we use to spot the cells Speaker 1: 02:19 to this instrument and its ability to precisely place tiny drops of cell matter. This device can hold 2000 different strains of live eco lie. These eco lie, which are not harmful to humans each have a special property. So we've genetically modified the Cole eye to light up when a specific metal is present and under a special light, they glow such Husky points to openings on the chip or you see these dots, that's where the metals go in. And then the cells will respond to the presence of the metals by fluorescing bacteria interacts with metals, but usually tests with bacteria only sends one metal at a time. So researchers built this device with thousands of genetically modified bacteria types to detect many toxins at once and in real time. Speaker 4: 03:01 And you would plug it in with media provided and then hook up a water line to it and it would run. Speaker 1: 03:07 The cartridge is placed inside a box. There's a sensor that takes a picture and captures the equal lie as they interact with the metals so it can tell what's there and how much of it the box records and presents those results. But since the eco lie are alive, the owner would have to replace the cartridge with new bacteria every two weeks to a month. So Chelsea says this research took years to complete, but she believes it can have an impact helping people check their water around the clock. And so does Natalie Cookson Speaker 2: 03:35 founder of the startup quantitative bio-sciences in Sorento Valley Speaker 4: 03:38 we're trying to do is basically make it a much more robust system that you could rely on out in the field. Speaker 1: 03:46 Since 2015 employees at this company have been trying to turn the sensor into a product, anyone can get access, Speaker 4: 03:52 you could deploy our, our sensor in an area of concern where you might have, you know, lead contamination coming and going that way you would catch the event, you know right when it happened. And Speaker 1: 04:01 Cookson says the company plans to deploy a sensor at a government site this year. Right now, the package costs around $5,000. She says the company wants to collect more data to show that the sensor works in the field Speaker 2: 04:12 and they want to make it smaller and cheaper, so more people can buy it. Speaker 4: 04:15 We could get one of these in every, you know, drinking fountain at schools, for example, or even in homes. Speaker 2: 04:20 In the meantime, back at San Diego unified facilities manager, Naji says he's definitely interested in following this technology. That's because clean water is so important for the health and growth of kids. Like the ones at Edison elementary. Shelina Lani KPBS muse Speaker 1: 04:38 joining me is KPBS science and technology reporter. Shalina Chet Lani Shelina welcome. Hi. Glad to be here. So this eco lie bacteria they're using is not harmful to humans. This is a different bacteria than the one that causes illness. Yeah. So it's not a different bacteria, but it is grown in a lab. So they've genetically modified this particular Ecolab to not be harmful to human health. Uh, it will sit okay. And the human gut, for example, of course, they don't want the Ecolab bacteria to actually get into the water. Um, that's not what the product does, but if it were to leach into the water, it wouldn't harm humans in any kind of way. What makes it glow when it interacts with led? Yeah, so that's part of the genetic modification that they've given them a type of protein that allows them to floor us when they come into contact with heavy metals. Speaker 1: 05:30 So it comes from a certain protein that they have been modified to accept. Is the idea that a box with this bacteria could constantly monitor led and other metal levels in drinking water? Yes. Right now, uh, when it comes to water testing, the problem is that, you know, you can, you can have cheap at home tests, um, but you might only be able to do those at certain points and they may not be as wide in scope as you needed to be. And then when it comes to larger sampling, you can't do those very frequently and they can be expensive. Um, for an entire school district, for example, that could cost hundreds of thousands of dollars at any one point. And there aren't, you know, clear standards really on how often you should be testing the water. It could be every month, it could be every six months. And what the problem with contamination and water is that it happens in bursts. Speaker 1: 06:23 It doesn't happen continuously. So there might be a leach into the water system for example. And so the idea behind this box is that you, you hook it up, you, you have it running to some water source and it'll be able to tell you through its automatic, uh, AI system, whether there are elevated levels of a range of particular contaminants. So how does the information get relayed from the box to monitors? How does it, as you say, spit out the results? Yeah, so when I was at quiet quantitative bio-sciences, basically what it was doing was sending the information that it had analyzed and gathered to a computer system. And you can read those results, um, on a monitor. So right now I think what they're doing is trying to finesse that so that it's a little bit more accessible to any person that wants to see what the results are. Speaker 1: 07:16 Basically the, the box has an entire AI system within it back in automatically sort of see what the changes in the Ecolab bacteria and then render those results onto a screen. We all know about the real tragedy in Flint, Michigan with lead in the water, but it overall generally speaking is led or heavy metal contamination in water. A big problem. It's definitely a big problem. So, uh, right now the EPA is action level for lead is around 15 parts per billion in, in an amount of water. There's a lot of research that's come out that says even five parts per billion can be really damaging to a child's health, to a child's growth and development, um, and even smaller amounts. And the reason why is that lead is a metal that causes permanent damage on brain development. So there's a lot of news out there about children in Flint, Michigan post this water crisis, which began in 2014 that shows teachers saying that they've noticed students having slower cognition or mood changes. Speaker 1: 08:22 These are the types of impacts that go on for years and might develop or might impact their, their brains. Um, for for years going forward now the setup that's going to be tested now costs about $5,000. You say for each individual one, how much less expensive do developers think they can make it? I know that there are certainly trying to make it so, so much cheaper that eventually the average family might be able to afford it. It's something that they're still working on the PR, the issue with the box is that it includes this optical imaging system. When the, when the eco like glow, you have to take a picture of them to see what they were like before and after. And that's how you know the change in the concentration of metals. Right. And so it's all about making this whole device smaller and using fewer parts. Speaker 1: 09:11 And so this is something that they're still troubleshooting right now. What government's side is going to be the first to deploy this sensor? The CEO of quantitative bias in sciences didn't like name the government site, but it's an environmental, uh, monitoring sites. So it's a, it's a government site where they are doing environmental monitoring already and they're going to be testing out this device in the field to see if it works better than current technologies with water testing it. Tell me some more about this startup quantitative bio-sciences it sounds as if they're trying to develop more biologically based ways to measure things. Yeah. The cool thing about this startup is that the founder actually worked in the same lab as the CSD scientists that I talked to. And so she took the ideas that came out of this lab and really cared about taking research to market in a very practical way. The quantitative bio-sciences has been around, um, much before 2015 and they were working on synthetic biology essentially. So synthetic biology is the same genetic modifications of micro organisms to make them, uh, react in a way that can help us see certain things in the environment, like with the Ecolab glowing. And so, yeah, they've been working on other stuff, but since this research came about, they've really been investing themselves in creating this sensor. I've been speaking with KPBS science and technology reporter Shalina Celani Shalina thank you. Thank you.

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Scientists have genetically modified bacteria to glow when they interact with metals.
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