[00:00:00] “Decompose” Theme Music

[00:00:05] Anne Chappelle: We’ve been doing Adverse Reactions, and this is what our 

[00:00:08] David Faulkner: Fourth

[00:00:09] Anne Chappelle: Fourth

[00:00:09] David Faulkner: Season

[00:00:10] Anne Chappelle: Season

[00:00:11] David Faulkner: Amazing. 

[00:00:11] Anne Chappelle: So, David, do we have a theme? 

[00:00:13] David Faulkner: Everything is so much more complicated and interesting and more interconnected than we ever think it’s going to be. 

[00:00:22] Anne Chappelle: We’ve really kind of strayed from traditional toxicology in this season.

[00:00:28] David Faulkner: It’s true. We have been expanding the reach of what most people think of as toxicology because one of the things I love about this discipline is that it is a necessarily applied science and that means it touches basically everything—all the other sciences.

[00:00:44] Anne Chappelle: Have a listen.

[00:00:45] “Decompose” Theme Music

[00:00:51] David Faulkner: On this episode of Adverse Reactions,

[00:00:54] Anne Chappelle: “Testing the Waters,” with Kari Sant, an Associate Professor at Michigan State University.

[00:01:00] Kari Sant: The first question I got asked when I was on the panel was, “Hey, could this happen in reality?” I was there to be a public health expert, and I had to give a little bit of background information where we’re exposed to fungi all the time. We eat mushrooms, etc., but fungi have a really hard time colonizing our bodies because they don’t like warmth. They don’t like heat. So, our body is really effective at rejecting them. There are a few other fungal diseases, things like athlete’s foot, thrush, etc., where we do have fungal diseases, but most of the time our body’s pretty effective at removing them.

[00:01:31] “Decompose” Theme Music

[00:01:34] David Faulkner: Welcome to Adverse Reactions. Today, we have with us Associate Professor Kari Sant, PhD, MPH, recently joined the faculty at Michigan State University, Department of Pharmacology and Toxicology, College of Veterinary Medicine. Thank you for being on the show with us today, Dr. Sant.

[00:01:52] Kari Sant: Thank you. First-Time caller, longtime listener so very excited.

[00:01:55] David Faulkner: Oh, it warms my heart to hear. Want to start out with the question of what is it you would say that you do?

[00:02:02] Kari Sant: I am an environmental toxicologist, an my expertise is in primarily developmental toxicology with a focus on environmental contaminants. I’ve been in a School of Public Health for most of my career, and there’s been a lot of opportunities to do a lot of community-engaged research.

When somebody comes to me from the community and says, “Hey, I’ve always wondered about this. We’ve heard that this contaminant was really high in our area. Has anybody looked into that?” I’ve jumped on those opportunities because honestly, it’s a lot of fun, and they’ve become my passion project. So, I would say more broadly environmental toxicology with a focus on development.

[00:02:37] David Faulkner: Yeah, looking over your list of publications, there is a lot of variety here. I think my favorite is a study that looks at teen use of nicotine vape products and garbology.

[00:02:48] Kari Sant: Oh, yeah.

[00:02:48] David Faulkner: Can you tell us a little bit about that?

[00:02:51] Kari Sant: Yeah. I didn’t know garbology was a field before that project, so that tells you exactly how diverse that one is. But yeah, I had a colleague, now colleague and collaborator, who came to me from UC San Francisco who was a garbologist. His job is to look at mostly product use through waste streams, but he got really interested in tobacco products and primarily the end game for tobacco use in the US. When all the new heated tobacco products and electronic nicotine delivery systems came online, vaping products, etc., his job was to look at waste of one-use in particular. And then, what we’ve done is look at, “Okay, these are getting into the ground. They’re being thrown all over the place based on our experience. Now, how do we assess whether or not that’s going to have a lasting environmental impact?” So, we teamed up for what’s become, again, a really cool passion project 

[00:03:42] David Faulkner: So, what kind of things did you find in that, or is this an ongoing project?

[00:03:46] Kari Sant: It is an ongoing project still, but we’ve got a bunch of really cool findings. So, a lot of my research in the laboratory uses the zebrafish model. So, the nice thing about that is we can translate that to human health because zebrafish have fairly similar structural development to humans, and they also share more than 70 percent of genes with humans. But additionally, guess what? They’re a fish. They’re a really good model for other fish species. So, a lot of what we’ve been looking at is when these get into our waterways—because they undoubtedly do when it rains—is that going to lead to issues in the aquatic ecosystem? So, we’ve looked at basically a bunch of product types and compared them to conventional cigarettes, and I will say vaping products, there’s a lot of liquid left in those when they’re discarded typically, and they definitely dump a bunch of nicotine into the environment. So, yeah, we’re finding a lot of toxicity there.

[00:04:33] Anne Chappelle: So, when I think of you being able to study on so many different things, I think of a chef in their kitchen that’s got all the tools that they need. So, they just, “I want to make an omelette. I’ve got all the fancy stuff.” So, when you’re thinking about the kinds of research projects, how do you decide, “I could do that”?

[00:04:54] Kari Sant: Yeah, I think it really comes down to two things: What my model is good for, and what my expertise is in. From an expertise perspective, as Sir David Faulkner knows, a lot of my early work, especially in my dissertation stuff, looked at a lot of genetics and epigenetics, anything that uses especially molecular techniques and sequencing, etc. I feel really comfortable working on those projects. We do a lot of transcriptomics in my lab and do that comparatively from a risk framework. I really enjoy doing that kind of work even when noncanonical, and somebody comes to me with a very uncanny idea.

But really, it comes down to a lot of it, is zebrafish an appropriate model to study? If somebody wants to look at pathology—not that you can’t do pathology in a zebrafish, you can—but they’re pretty tiny and zebrafish are marvels and can actually regenerate some tissue, so they’re not the best tissue-injury model.

Also, if they want to look at a chronic study, for example, if we wanted to do carcinogenesis, there’s plenty of people who do that in fish, but doing a long-term study in zebrafish is still two years, much like mice, versus a developmental study, zebrafish are actually really advantageous because it’s a really shortened window of development over roughly three days instead of over several weeks in mice and rats. So, we can do that. They’re really easy to genetically manipulate. So, if you do want to study gene-environment interactions, they’re a fantastic model. Because especially with new technologies like CRISPR, etc., zebrafish are very easy to inject and modify. We use them in a lot of high-throughput screening studies for that as well.

[00:06:26] David Faulkner: So, you study many things in the environment. You’ve talked about zebrafish as a model species, something that you’re very familiar with. I imagine that you do a lot of water-quality work. Is there a water toxicant that is of particular interest to you? Are there specific questions that are of particular interest to you?

[00:06:44] Kari Sant: I’ve worked with diverse toxicants. I think most of what I work with is in the endocrine-disruption realm, but one of my projects recently that we’ve gotten involved with, especially with these zebrafish screens, has actually been an oldie but a goodie, which is DDT.

So, I work with a team of scientists in Southern California from my former institution, SDSU, and collaborators at other institutions, including the San Diego Zoo. And what we’re looking at is, there were a number of barrels that were dumped off the coast of Catalina Island, just off the coast from Los Angeles for those that aren’t Californians. They found roughly about 40,000 barrels dumped in the ocean right there, and a lot of those are believed to have contained DDT from back in the day. Around those areas, they’re finding really high concentrations of DDT and its metabolites and other byproducts in a lot of the wildlife, including marine mammals such as whales and dolphins, but also in the fish.

So, we have a really great collaborative team right now where we’re collecting tissues from stranded animals, from fish, etc., and measuring all these new DDT products. Because, really, we’ve only studied a handful of them, but there are almost 50 of them that are actually in these mixtures. My job has been, “Okay, we know what DDT does, but what do all these other compounds do, and is there an additive effect? What’s the relationship between them?” So, it’s been a community partnership driven by lots of different science agencies to work on something super practical, which I love.

[00:08:08] David Faulkner: Wow, and that’s always the thing in academia, right? It’s so easy to just be like, “Oh, this is such an interesting question to me and nobody else.” But the benefit of public health or toxicology research is that it’s always practical to some degree, 

[00:08:21] Kari Sant: And we had this other project. This is really out there, but I actually presented this work at SOT last year, which I never thought would happen. When I moved to San Diego, I loved going in the water. I’m just originally a Michigander that moved to San Diego. Water’s my jam.

One of the things that caught my attention, when I took a group of students just to the coast to do some water-quality sampling—I was teaching water quality at the time—everybody told me how horrible the beaches near the border were. And I didn’t really understand all the politics and everything that went into that, but there’s a large amount of runoff that goes into the water system called the Tijuana River Watershed at the US-Mexico border.

There wasn’t really a lot of data on what’s in that other than standard E. coli measurements. We teamed up with another group of scientists—and actually we’ve partnered with community groups as well to do some of the sampling, etc.—to do some non-targeted chemical analysis to see which chemicals are in there but also do some metagenomics to sequence and see what pathogens might potentially be in there.

That was really outside of my comfort zone, but it was a passion project that was in my backyard, and my background in genomics helped me get a start on that. So again, all this has unfolded, but it comes from my love of the environment, making sure our waterways are safe, and applying toxicology and my background to cool projects.

[00:09:37] David Faulkner: Nice. Oh, that’s awesome. So, for the listeners out there who might not know what metagenomics is—I, of course, know what that is and don’t need a definition. I’m a very big brain, very smooth brain individual. Could you give us a quick definition of metagenomics?

[00:09:54] Kari Sant: Absolutely. Metagenomics are similar to a concept that most people might know, which is the microbiome, but metagenomics is the sequencing of kind of collectively all the DNA and sometimes the RNA as well in a sample. For example, if I was to do standard microbiome sequencing, I might use a technique called 16S sequencing, and I would know all the bacteria that are in a sample. But with metagenomics, I can find fungal contamination. I can find all kinds of levels within diverse kingdoms, everything that we get really a whole ecosystem picture of all the DNA that’s in that watershed. From a public health and toxicological perspective, it allows us to look at some of the other things that might cause disease that we might have missed just doing general microbiome sequencing.

[00:10:41] David Faulkner: Okay. So, like algael blooms or algal blooms, that sort of thing? 

[00:10:45] Kari Sant: Absolutely. 

[00:10:46] David Faulkner: Thinking about the Tijuana River, right? This gets at something that I think is really important, which is the idea that water doesn’t respect administrative borders. It doesn’t have any sense of, “Oh well, I can’t go over there because that’s across this border.” So, what kind of complexities does that create in your research?

[00:11:05] Kari Sant: Oh, man. Yeah, it’s huge. And I think from a regulatory perspective, this is a big deal because there are a number of compounds, for example, that are banned in the United States that are not in Mexico and are still sometimes in use in Mexico. So, as all of those are getting into the runoff and then coming across the US-Mexico border into Imperial Beach and San Diego County; they often contain some of those compounds, So, even though we’re regulating in the US, sometimes at point source, we’re unable to mitigate that across the border without international cooperation. So, it’s a huge political issue, and right now, we’ve started getting a lot of traction with partnerships on both sides of the border to help work on cleaning up some of the engineering controls issue to actually help with the water treatment aspects, but also to make sure we understand what the actual environmental problems are. Because a lot of this had come from word-of-mouth from the community for people that lived around there saying, “My water smells.” Things like that that they were reporting to us. “I got a rash after surfing, etc.,” but there hasn’t necessarily been follow up on that. So, by providing some scientific evidence to help back those claims, hopefully we can know what sorts of. improvements we can make to improve public health.

[00:12:16] Anne Chappelle: How does some of the stuff that you’re doing, how do you extrapolate for these different susceptible populations? Because it’s one thing if you are 85 years old and you live next to the river. It’s another thing if you are a small child playing at a sprinkler near the Tijuana River.

[00:12:36] Kari Sant: We’ve all seen babies; they’re crawling around all the time. They’re putting their hands in their mouths, right? So, as these things are getting tracked in the households, they also may have higher exposure just through consumption like that as well. So, getting at that issue, a lot of my research has focused on childhood exposures. Even some of the metagenomics, etc., our plans now are to do an epidemiological study where we’re going in and doing hand swipes and things like that to actually see how much of this water contamination is making it into the home? And then, likewise, since children are the ones that are most likely to be exposed through those mechanisms, what is the direct exposure to them versus some nebulous environmental exposure in particular?

[00:13:16] Anne Chappelle: So, you’ve recently switched institutions.

[00:13:19] Kari Sant: I have. 

[00:13:19] Anne Chappelle: Starting afresh at a new school, a new university, you’ve got a lot of work ahead of you with a new teaching, with your new graduate students. This is a huge undertaking that maybe people don’t necessarily realize when they switch universities.

[00:13:35] Kari Sant: Yeah, starting a lab is hard. In some ways, it’s a curse. In some ways, it’s a blessing. And you’re catching me right in the middle of it. So, I laughed—maybe right now it’s a little bit curse, but it might be more blessing later.

The challenge there is, for example, I had a great team working with me at San Diego State. Having to upend every, in my case, all of my research and move it here with a new group of people is always really challenging. And there’s always the challenges with ordering and things like that coming through.

But it’s also fun because, think of it as, I started up a lab. I learned what I liked and what I didn’t like. And now I can improve upon that when I start up my new one. For me, it’s like a fun shopping spree in a lot of ways, where I get to shop, I get to buy exactly what I want, and I know what that is really clearly now.

But yeah, my research is very similar across institutions. Being somebody who works on environmental contamination, focused on water—San Diego had a lot of water, being coastal waters; Michigan has a lot of water, we’re surrounded by water. I have water 100 feet from my house. So, it’s one of those things where I get to work on the same sorts of issues but with slightly different populations and slightly different contaminants. So, even looking at pesticide use, the pesticides that were used and primarily contaminate California are different than those that I would find around here in a lot of ways. So, it’s challenging to relearn and get that institutional knowledge about community practices and what the cultural norms were here 30 years ago in terms of use. But it’s fun because it’s applying the same sorts of paradigms to a new challenge, which I love.

[00:15:12] David Faulkner: I wanted to talk about your science communication at Comic Con and just Cons in general—conventions. First of all, I guess, let’s establish for our listeners who may not be as familiar with what these are outside of SOT or trade shows. What is like Comic Con? What kinds of things are you going to, and what are you doing there for science communication?

[00:15:34] Kari Sant: So, Cons are conventions just like at SOT where you go and there’s a lot of vendors selling things like their own art, etc. But I’m a huge nerd. I go to cons all the time. 

[00:15:45] David Faulkner: What?!?

[00:15:45] I really enjoy them. Huge nerd. 

[00:15:47] David Faulkner: You’re a nerd? No. 

[00:15:48] Kari Sant: San Diego Comic Con is world famous. When it comes to the Cons, San Diego Comic Con is the golden standard. A lot of different movie launches, etc., all happen at San Diego Comic Con. You can go to panels that have your favorite celebrities talking about the roles that they played. You can go to other panels where people are talking about new comics that are being released. There’s everything under the sun related to nerd culture, as it’s affectionately called. I go to that as a fan. But luckily, I’ve now had the opportunity to be speaking as a panelist now at San Diego Comic Con. So, total bucket list. 

[00:16:22] David Faulkner: Amazing 

[00:16:23] Kari Sant: But there’s a lot of science communication panels now. I think they really realized the Venn diagram of who likes Comic Con and scientists, really, those are pretty close to overlapping circles. So, a lot of the panels now are actually science communication panels there. They’ll bring in experts to talk about a new show or a new comic, and either is it real or how could this happen sorts of aspects of it. 

Last year was probably my favorite that I got to do, which was I was on a panel called “Fear and Fungi: The Science of The Last of Us.” for those who are unfamiliar, The Last of Us was a video game now turned HBO very popular series about a zombie apocalypse. But it’s all based on there’s a massive fungal outbreak that happens in the environment, and they’ve mutated, etc., to gain the ability to colonize humans. And it causes this disease that turns people into zombies. So, it’s actually an apocalyptic, end-of-the-world story. It’s a beautiful story. But it’s really rooted in science and really pathology, which is pretty cool from my perspective.

[00:17:30] David Faulkner: Oh, yeah. But also alarming. So, can you give us like the top lines, like how realistic or what are the real science aspects of that show?

[00:17:40] Kari Sant: The first question I got asked when I was on the panel was, “Hey, could this happen in reality?” I was there to be a public health expert, and I had to give a little bit of background information where we’re exposed to fungi all the time. We eat mushrooms, etc., but fungi have a really hard time colonizing our bodies because they don’t like warmth. They don’t like heat. So, our body is really effective at rejecting them. There are a few other fungal diseases, things like athlete’s foot, thrush, etc., where we do have fungal diseases, but most of the time our body’s pretty effective at removing them. However, the show starts off in the game with this beautiful premise of climate change being a driver of how this could happen whereas climate change and global temperatures are increasing, these fungi get more and more tolerant to higher temperatures to where they can eventually colonize human bodies. So, I got to give a little bit of an evolutionary biology talk but also an epidemiology talk. You’re taking a ton of information and condensing it down to 10 minutes. But it’s a show and a game I love, and it’s a topic I love. So, it was the perfect scenario.

[00:18:46] Anne Chappelle: I do find it interesting when we can find those connections to a Comic Con or I gave a talk once at a Mensa meeting, I’m not Mensa, but I was asked to speak there on junk science, and there really is a very good intersection between what we do in terms of assimilating information and seeing if things are rational or not. It’s very fascinating and finding places where nerdiness is put on a pedestal. 

I’ve been to some Cons myself with my child. It is fascinating. I love the creativity, but the idea of is there a bit of truth in those comics, those TV shows, enough to get you hooked.

And I honestly do hope that there is what I’m calling the Fauci effect—that as a result of the pandemic that you have a lot more people interested in public health. Just like, CSI spawned this whole generation of people that were interested in forensics. I’m all for TV and other medias inspiring us to try and do this really cool, funky stuff.

[00:19:57] Kari Sant: You know, it’s funny you say that. One of the most rewarding and cool things that happened were people who come up to you after having these sorts of conversations. One was a college student who was in town for San Diego Comic Con and goes, “Huh, my mom was a toxicologist. It’s nice to meet another one and to actually learn more about the different applications in public health because I’m interested in public health.” I said, “That’s a huge field” and gave him some pointers on that. And likewise, I think, we’ve had younger people come up to us, smaller children around the age of 10 to 12, come up and talk to us afterwards who are just interested in science and wanted to get started and just to hear more about the sorts of things that we do and that can make a huge difference. 

So, at SOT last year, I’ve never will forget Jim Luyendyk gave the talk about how seeing The Rock with Nicholas Cage being a toxicologist inspired him to become a toxicologist, which I totally agree on for the record. 

[00:20:46] David Faulkner: Yeah. Yeah. This goes back to your professorship, being a communicator, being a teacher, because teaching is communication, and a lot of people, I think, don’t realize that.

[00:20:57] Anne Chappelle: So, would you rather be in front of students teaching, or would you rather be in the lab?

[00:21:04] Kari Sant: Ooh, what a great question. I think my answer to this has evolved over time. For those who don’t know, David Faulkner and I went to graduate school together back in the day. We were actually in the same lab for a short period of time. And back then, I actually got my PhD because I loved teaching.

I loved teaching. I wanted to be a full-time lecturer/instructor. I was doing a ton of TAing, etc., but I also loved the lab. The next thing for me is I have a job where I basically get to do 50/50. So, about 50 percent of my job is just research, writing papers, writing grants, but 50 percent of my job is not only just teaching but also mentoring students, which is teaching in the lab. For me, I think my natural state is teaching. My mom was a teacher. I’ve always loved teaching. On the side, I’ve even taught things like knitting classes and stuff. I love teaching. But I do love research, too. I like the question-driven thrill of being able to do scientific research. So, it’s a little of both, but if I was by myself in a lab, I wouldn’t like research as much as I do getting to mentor people.

[00:22:06] David Faulkner: I will say that we are coming up on the end of our time here today, sadly, but we do have some questions that we like to ask everybody. My favorite question is always, “What would you be doing if you were not doing what you are currently doing?”

[00:22:20] Kari Sant: The sweet irony—and I was just telling people this morning—if you look at what I wrote down from when I was age four until honestly when I went off to college, I found this cute note to my mom for Mother’s Day. It was like, “When I grow up, I want to be a veterinarian and go to Michigan State University.” So, it’s hilarious that I’m in the College of Veterinary Medicine here now. I always wanted to be a veterinarian.

[00:22:41] David Faulkner: Wow.

[00:22:42] Kari Sant: That was it for me. I wanted to be able to improve health among the entire ecosystem. Not that I don’t care about public health. I love public health, but I always wanted to be a vet.

[00:22:52] David Faulkner: Is there a particular animal that you are interested in?

[00:22:54] Kari Sant: Back in the day, of course, I liked all the cute furry things. Now, if I was being asked this question, I like working with all the cute marine mammals. Being able to work with the seals and the dolphins and the whales has been really cool because they do have such a vibrant ecosystem. And from a toxicologist perspective, that’s interesting to me because we see a lot of the challenges we do in humans translate to them.

[00:23:16] Anne Chappelle: I always ask—our show is called Adverse Reactions—what was your biggest adverse reaction? 

[00:23:24] Kari Sant: Oh, man. Of course, I’m not prepared for these questions at all as a longtime listener. For me, I’m the first to admit I was not a good student. I was okay. I was adequate, but my GPA in college, it was fine. It wasn’t great. I didn’t enjoy being in the classroom necessarily, maybe for all the reasons we discussed earlier. But what it came down to was not learning how to learn ever and just getting by on perhaps intelligence. But as I got to prioritize myself more and more as I got older, that got easier and I started having fun with it, right? For a long time, I was just there to get it done, check a box, and move on with my life. I think my biggest adverse reaction was learning, “Man, maybe I’m just not that good of a student.” Despite the fact that I’m a professor now. Who would have thought?

[00:24:09] Anne Chappelle: I, too, had a mediocre GPA in college.

[00:24:14] David Faulkner: Same. 

[00:24:14] Anne Chappelle: To me, anyone can start a PhD program. It’s the people that finish it. People are like, “Oh, I can’t believe you have a PhD.” I’m like, “You could do that, too, if you work hard enough at it.” We’ve all shown that if you give us the right learning environment, if you give us the right instructors, and you give us the right subject, that we can excel.

[00:24:34] Kari Sant: It just takes one. And for me, it was funny because I had taken all these classes, but I took my first actual lab class—not just the dumping stuff around but actual like you had to develop a hypothesis and test it—and I didn’t take it until my, I did five years of undergrad, until my fourth year. And I realized, “Oh my gosh, I like research.” And I was told by others, “Hey, it might be an easier A than going and taking exams.” And that’s the only reason I got into it to be honest with you. So, it’s funny how that all played out.

[00:25:03] Anne Chappelle: Thank you so much for joining us today 

[00:25:07] David Faulkner: Thank you so much for coming on the show. This has been so much fun. It’s always great talking with you. 

[00:25:09] “Decompose” Theme Music

[00:25:15] Anne Chappelle: Thank you, all, for joining us for this episode of Adverse Reactions presented by the Society of Toxicology.

[00:25:23] David Faulkner: And thank you to Dave Leve at Ma3stro Studios,

[00:25:26] Anne Chappelle: that’s Ma3stro, with a three, not an E,

[00:25:28] David Faulkner: who created and produced all the music for Adverse Reactions, including the theme song, “Decompose.”

[00:25:35] Anne Chappelle: The viewpoints and information presented in Adverse Reactions represent those of the participating individuals. Although the Society of Toxicology holds the copyright to this production, it has,

[00:25:46] David Faulkner: definitely,

[00:25:47] Anne Chappelle: not vetted or reviewed the information presented herein, 

[00:25:51] David Faulkner: nor does presenting and distributing this podcast represent any proposal or endorsement of any position by the Society.

[00:25:58] Anne Chappelle: You can find out more information about the show at adversereactionspodcast.com 

[00:26:03] David Faulkner: and more information about the Society of Toxicology on Facebook, Instagram, LinkedIn, and Twitter.

[00:26:09] Anne Chappelle: I’m Anne Chappelle, 

[00:26:11] David Faulkner: and I’m David Faulkner. 

[00:26:12] Anne Chappelle: This podcast was approved by Anne’s mom.

[00:26:14] “Decompose” Theme Music

[00:26:19] Episode Ends