Ep. 563 - The Harmful Consequences of Mosquito Sprays

Conversations like you're about to hear do not happen unless you support In Defense of Plants. And now more than ever, we need conversations like this to reach as many ears as possible. One of the best ways to help keep In Defense of Plants up and running is to become a patron over at patreon.com slash indefenseofplants. In return for a tiny bit of support each month, you will get access to a completely separate podcast. It explores a lot of really fun gardening topics, everything from seed collection and storage to growing native plants, the struggles of trying to garden in different climates, and so much more. It's a heck of a lot of fun. We're learning so much, and we're trying to share that with you. So come on and join the Patreon over at patreon.com slash indefensiveplants and help keep this show up and running in the process. I hope to see you over there. But in the meantime, on with the show. Hello, everyone, and welcome to the Indefensive Plants podcast, the official podcast of indefensiveplants.com. What's up? This is your host, Matt. Welcome to the show. How is everyone doing this week. Listen up, this is a really important episode. We are talking today about pesticides, specifically those targeting mosquitoes. And targeting is the wrong word to use here, because what can be sold as very specific types of pesticides to remove pests like mosquitoes from your yard are actually hurting so much more than just mosquitoes. Now, throughout this episode, we are not downplaying the negative effects that mosquitoes can have on the human population worldwide. We understand that mosquitoes are important disease vectors, and this is a very big topic that can't be covered on a plant podcast. But it is important to know what kind of impact we're having on our local ecosystem when we try to control these things. Joining us to talk about this is Dr. Aaron Anderson from the Xerces Society for Invertebrate Conservation. And he and his colleagues have done really important work looking at the impact of mosquito fogging in particular in suburban and urban neighborhoods and what this means for other insects like pollinators, butterflies, you name it. It's sobering, but it's a really important conversation to have. And stick around and listen to this episode in its entirety because there's a lot of actionable items in here and a lot of great resources to help you keep this conversation going. So I don't want to keep it from it any longer. Let's just jump right into it. Without further ado, here's my conversation with Dr. Aaron Anderson. I hope you enjoy. All right, Dr. Aaron Anderson, welcome to the podcast. It is so great to have you here. Let's start off with an introduction. Tell everyone a little bit about who you are and what it is you do. Hi, Matt. Thanks so much. And yeah, I'm excited to be on the podcast with you today. So yeah, my name is Aaron Anderson. I'm a pesticide program specialist at the Xerces Society for Invertebrate Conservation. And I do a lot of work working in residential areas with residential gardeners, home gardeners, community gardeners, also sometimes parks departments, trying to encourage pesticide reduction, alternative pest management practices, and also just in general, pollinator conservation, invertebrate conservation at large in these kind of residential urban landscapes. It's a great position. And I think from my perspective kind of an intimidating one it's too because you're spanning that gap between the ecological side of the science and what we know is good for organisms like invertebrates insects especially but also trying to communicate that to a public who is largely and i'm not saying this in a negative connotation but ignorant to a lot of what's going on out there uh or want to maybe do something better and that communication skill set is something that i think is is vastly important And very few people get to apply that both sides of the spectrum. Yeah, totally. No, I feel really lucky with the role I ended up here at Xerces because, like you said, sometimes there's challenges. But it's also incredibly rewarding to work with the public. And I think when I'm doing some sort of outreach, if I'm doing a talk, if I'm doing a tabling event, and somebody who has no idea that pollinators or bees can look like anything other than a honeybee when they have that kind of light bulb moment, it's really, really satisfying. And I think just, you know, doing that type of work, talking to people, letting them know how important insects are, how important pollinators are, is just, yeah, really core to kind of, yeah, the work I find important. Big time. Yeah. And I find, like, from an organizational perspective, a lot of people, what are your metrics for change? How are you moving the needle? Can we measure this? And sometimes it isn't that tangible. I mean, can you pick that person out of a lineup and say, can you write on a piece of paper that? But seeing those light bulbs go off truly are like the most magical moments for any science communicator to go, oh, this is something new for this person and they've got it. And maybe, you know, it's not like changing an entire country's policy, but that's that's the groundwork. This is where it happens. Right. Totally. No, I think you're totally right. I think that what I find really inspiring, you know, doing this work is, you know, we can reach people. I have colleagues doing amazing science research. I have colleagues doing amazing policy work, which is all incredibly important too. But then, yeah, getting to kind of work with members of the public, I get so inspired when there's people who are doing this on the ground grassroots work who are reaching out to us, you know, asking for resources, asking questions and getting to see the type of work they're doing in their own communities. I can put a quick plug in for our Bee City USA or Bee Campus USA program in Xerces, which is an arm of Xerces. And affiliates are towns and cities or campuses who pledge to become bee cities and to conserve pollinators, reduce pesticide use. And seeing the work they're doing, the outreach they're doing in their communities is really inspiring to me. So, yeah, we really need that kind of grassroots up to well, I think, to kind of make a difference. Excellent. And what brought you to this work? I mean, was it a communications thing or were you more of an entomology kind of student? Like what what made you come to this role? It's a great question. Yeah. So I would say I'm a general kind of insect ecologist. OK. Yeah. So my background was kind of general ecology and evolution in undergrad. And I worked in an entomology lab. But, you know, some of my my classmates and co-workers were really hardcore entomologists. And I thought insects were cool, but I also thought plants were cool. you know, all sorts of things were interesting to me. So then afterwards, I did a couple kind of AmeriCorps internships doing restoration work, which was great, you know, got to do some injured butterfly conservation, and then did some work in biocontrol before going back to grad school. And what I ended up focusing on in grad school, and what I guess I should take a step back, what one of my positions was, was restoration intern in the Golden Gate National Recreation area in San Francisco and we were doing mission blue butterfly conservation and obviously San Francisco is this big urban sprawl but there are these little patches of you know mission blue butterfly populations kind of dotted up through the San Francisco Bay Area and you know that was kind of I think the first time I started thinking about ecological function in urban areas and thinking like okay we have these little patches of populations but you You know, the mission blue butterfly, a little like Xanity, can't fly very far. It's a weak flyer. Like, you know, there's never going to be, you know, movement between these populations. So then starting to think, like, where, you know, could you build habitat through this area to kind of connect these areas was something that became interesting to me. So then I kind of became interested more in general, just how do we incorporate ecological function into our urban, suburban, you know, residential landscapes. So then I went back to grad school with Dr. Gail Angolotto at Oregon State University. And our lab there was the garden ecology lab. So it was all about the ecology of gardens, which was really cool. Felt really lucky to end up there with with Gail and some of my other grad students that were doing just really cool garden ecology research. And I felt lucky we were able to do that because, yeah, kind of an understudied area gardens. So with the kind of increase in attention pollinator conservation is getting, one of the things that Gail would get at the lab and we would get were master gardeners who would contact us and say, you know, what are the top plants to plant for pollinators? And, you know, the best answer is, you know, a diverse suite of flower native plants. All of them. All of them, exactly. But sometimes people were like, oh, I only have space for a couple or, you know, just give me three. And there wasn't a great kind of empirical answer we could give. So that kind of led into the research I started doing for my dissertation, which was screening. We did, I believe, 27 different native, because of the Northwest, kind of native to the broader Western United States, wildflowers to their attractiveness to pollinators, natural enemies, but then also to gardeners, too, because we didn't want to find a great powerhouse pollinator plant that was really ugly and really weedy. weedy and nobody would have to plant their gardens. So that's what I did for my dissertation. And that kind of put me on this more pollinator path. But then I got to do a lot of outreach to gardening groups, to master gardeners, to different types of native plant organizations through that work, which really gave me experience, but also made me really interested in the kind of outreach component as well. So then kind of, yeah, luckily I get to do both of those things here at Xerces. Yeah, yeah, that's an awesome and like, you can never plan a trajectory like that you kind of take the opportunities and where you're fortunate and you know, just kind of take things as they come. But what a great path to set you up to work for a place like Xerxes Society for Invertebrate Conservation. I mean, this is the rubber hits the pavement kind of group. And you are really well situated in terms of background and passion, I think, for the kind of work that Xerxes is doing for the country for the world, really. And I guess I could kind of chime in really quickly. I realized I didn't mention it up top. But the Xerces Society, we've been around since 1971, working to conserve wildlife through the conservation of invertebrates in their habitats. We do a lot of on the ground conservation work. A lot of my colleagues work in agricultural landscapes, helping farmers be more pollinator friendly and increase flora resources on farms and reduce pesticide use. We do a lot of community engagement work. We have a lot of people working on endangered species, monarch rusty patch bumblebee and yeah we also have our pesticide reduction team which i'm on so yeah we really work on a lot of different types of issues and yeah i feel really lucky to be on this you know part of this large team of people working to conserve invertebrates yeah and it's great to see it done in such a multifaceted way and every avenue of approaching this is an important way of doing it we need a multifaceted but to think about this in the context of working landscapes and urban landscapes, like these areas that we desperately need as a species in our societies, but also areas that whether we like it or not, are growing year after year. And going back to the mission blue butterfly, like if they can survive in a place like this, and we could figure out ways to do it better, why wouldn't we? It's a win-win in the long run. I mean, it's changing, but it's changing in ways that aren't as negatively impactful for biodiversity. Right, right. No, I think that's a great point. Just trying to see, hey, where are those opportunities for us to do meaningful conservation work in our landscapes. Because like you said, we have urban expansion, there's agricultural intensification, and yeah, we have to kind of sometimes work within those constraints and try to save these species. Yeah. And working at the interface of sort of invertebrate conservation pesticides, it's got to be a rough spot to be in because there's a lot of very emotionally charged arguments on both sides. I mean, you have the people arguing for the economic side of things about increased production and food security for an ever-growing human population. And on the other side, you're like, well, we're erasing biodiversity in the process and there's got to be a better way. Is it difficult to take that leap, even though it is an important place to kind of interface? Yeah, that's a really good question. I think that there's, as you mentioned, pesticides can be a really charged topic. I think, you know, the current paradigm is that pesticides are necessary. Right. And I think that, you know, I have lots of admiration for my colleagues who work in the agricultural sector just because those are really challenging conversations to have because people are understandably concerned about, like you were saying, crop yield, pests, things like that. I think that in the kind of more residential urban park setting where I do a lot of my work, it's still a challenging conversation. But I think there's areas that are kind of hopeful because we can show examples of like, hey, you can solve these problems. You can manage pests. You can have a nice looking landscape without relying on these really toxic pesticides. And I think a lot of that, though, is just opening people's eyes to it. I think that, yeah, there's there's this prevalent idea often in our society that pesticides are necessary. They're the first line of defense when it comes to an unwanted pest or disease issue. You know, again, I'm speaking, you know, in yards, parks, places like that. And, you know, the first thing you do when you see something eating your plant is to reach for a bottle of pesticides. So I think the number one thing is, is, is that, you know, a challenge that I face is trying to talk to people, even people who are often, you know, educated, um, and, and experienced gardeners, uh, they still, you know, aren't necessarily aware that there are risks associated with these products, that using these products, isn't going to just kill the target pest. It's also going to, um, most of the times also put other organisms in your yard at risk, uh, and that there is other ways. And I should also note that it's not just about other ways of managing pests, but often it's reframing the issue. You know, one of the statistics we like to share is that, you know only about 2 of described insect species are what we might consider pests things that vector disease or might cause economic damages to plants The rest are really beneficial to us as humans and to the ecosystem. So something munching on your plant isn't necessarily a bad thing. And it might just be at levels that can be kept in control by beneficial insects. Obviously, even pest insects are serving an ecological role as well. So it's kind of reframing that. It's good that things are nibbling on your plant in your garden, because it means that it's being used as a resource. By all these really important organisms, all these important invertebrates that will support this healthy, you know, biodiverse landscape. Yeah, yeah, totally. And I am not going to sit here on a high horse and pretend I am not alarmed when I'm growing a new native plant species for the first time and something hammers it, you know, munches it back down to the ground. I have those knee jerk reactions, but you have to kind of like you said, take a pause, take a step back and go, okay, how can I maybe improve this situation. Maybe it's I germinate twice as many as I thought I needed, you know, that kind of thing. Or, you know, that those moments when you're like, can you guys just wait till they're mature? Like, please, there's going to be so much more food in like another year, but please wait. It's tough. It really is. But that home level, I think, doesn't get talked about nearly enough just because, you know, we look at our backyards or our front yards or our patios and we don't see this like earth covering sort of magnitude that you see in a farm scenario. But I talk about this with my colleagues a lot, is this idea that, okay, agriculture is actually pretty intensely regulated, especially at the industrial level. Not to say that scaling pesticide use back at that is not a good goal to have. But when they say, hey, just use it based on what you read on the label at home, you know, a box store and you bring it home, no one's looking over your shoulder to make sure that, you know, my neighbor Jack goes, well, if a little is good, more is better. That is oftentimes, I think, where some of the gnarliest stuff happens with these chemicals. Yeah, I think you're totally right, because there's no oversight or regulation when you're just spraying something at home. And often people want to see quick results. So they think, you know, I'll just apply a lot. And, you know, on a, you know, when you do some of the calculations on a kind of per square area basis, you know, oftentimes pesticide use at home is actually much greater than in agricultural areas. It can be really, really intense. So I think that that's a really great point. Yeah. And when you grow up on well water, you think about that stuff a little bit more than you do when you've got a nice metal impervious pipe bringing water to your house. But either way, thinking about this in the context of pesticides, one of the things that brought me to your work is this idea of a lot of the... Even I get it in the mail all the time. These pesticide companies, these lawn care companies will say, oh, we're targeting spiders with this, or we're targeting mosquitoes with this. How often is it that you do find a pesticide that is only specific to that one thing that that person actually cares about and not every invertebrate on the landscape? Unfortunately, that is generally not the case at all. They'll say, this is targeting mosquitoes, this is targeting ants, this is targeting spiders. But obviously, I'm speaking in broad generalities here, but generalities here. But unfortunately, you know, they typically use pyrethroids for nuisance pests, which are a class of insecticide that are broadly toxic to all sorts of invertebrates and are quite toxic. You might also hear them say, oh, this is derived from flowers, which is a common kind of tagline. And they're kind of right in the sense that pyrethroids are based off of pyrethrum, which is derived from chrysanthemum flowers. But it's still a very toxic insecticide and pyrethroids are the synthetic lab-made version which are made to be more toxic and more long-lived um so you know they'll be applying these uh you know either you know whatever the newton's pest is in the case of mosquitoes throughout an entire yard uh and unfortunately all of invertebrates that are going to come into contact with this are going to be at risk yeah because pyrethroids are really broad spectrum um but yeah so a lot of times that marketing can can be quite deceptive, a little bit misleading. But yeah, and it is unfortunate often how pervasive it is. Oh, it's bad. And I'm just basing this off of what I see show up in my mailbox, you know, and it's the amount of times people have come by or say, you know, door to door sales, which I didn't even know was still a thing in this age. But, you know, saying, hey, we can get rid of spiders. I'm like, but they do your job for you. Why would I get rid of the things that are, you know, taking care of some of the mosquitoes that get into my house, that kind of thing? right you're like why would i want to get rid of these yeah these are great yeah um yeah no i've heard i've heard of pretty aggressive marketing even even uh discounts if multiple houses on a block all sign up um so there can just be really yeah yeah intense marketing sales pitches uh and it's hard because if you're a well-intentioned homeowner you might not realize you might think oh yeah this is only going to impact you know this pest species that i don't necessarily want without realizing actually it's going to make your landscape toxic for everything else yeah and that's the point i want to drive home too is it's not like a lot of these folks are going out and saying i want to kill everything some of them really might love pollinators might love the fact that butterflies are coming to their asters and fall uh but at the end of the day you know what they're trying to target say the mosquitoes that bite them up when they're just trying to enjoy their their you know patio and the in the evenings that that's they're all invertebrates at the end of the day with similar nervous systems and and that sort of thing and you know again even if it's organic at the same time. So is ricin. I don't want to get any ricin in my bloodstream. Yeah. Yeah, no, one of the things I kind of like to message is, because people will ask about organic options. And often, of course, these are potentially less toxic, less long-lived than conventional insecticides. But still often, if it's designed to kill an insect, it's still going to be putting the beneficial insects at risk as well, not just pest insects. But yeah. So the reason I ended up finding your work in particular is because of this idea of spraying for mosquitoes. And I've lived in towns where it is just common practice to do this. And I've lived in towns where it's not a citywide thing, but it's definitely household by household. And speaking of emotionally charged arguments, I mean, the main mosquito I see in my neighborhood is the invasive tiger mosquito. It doesn't belong on this continent and it drives me nuts and it can be a disease vector. I can understand why someone would not want that around. But just as we've been talking about for the last few minutes here, the general treatments for mosquito spraying aren't just hitting the mosquitoes by themselves. Yeah, exactly. going back to those pyrethroids with these home backyard sprays, those are what tend to be sprayed. You know, when you hire somebody to come and do the backyard mosquito spraying, they're going around and they're spraying pyrethroids all over the vegetation in your yard. They're trying to both kill mosquitoes that are flying and roosting in that vegetation because often mosquitoes will roost during the middle of the day. Obviously, it depends on the species, but they'll roost there and, you know, kind of wait in the more shady, moist areas during the heat of the day. And not only are these designed to actively kill mosquitoes that are present at that point, but they also claim that it creates this barrier that's both repellent and toxic for up to three weeks. Generally, if you look at these companies sites, that's what they advertise. So, of course, if you're thinking about this broadly, you know, toxic insecticide that's being sprayed all over a yard, you would think that the potential for risk for beneficial insects is also really high. So that's actually kind of one of the reasons we did this study at Xerces. As I've been mentioning, we do a lot of work helping home gardeners, community gardeners, and other people create habitat within these urban and suburban landscapes. And we often get the question, you know, I'm creating a pollinator habitat, but my next door neighbor sprays for mosquitoes. How much of a risk is this to the bees and butterflies that I'm trying to attract to my garden? You know, the worry is that these yards are going to be ecological traps, essentially luring pollinators into what appears to be really high quality habitat when it's actually going to be poor quality, toxic habitat. And we didn't have a great answer to that. We didn't really know how much pesticide residue gets deposited in a yard near a yard that's sprayed for mosquitoes or how much of a risk it poses to beneficial insects. So that's that was kind of the impetus for doing this this study. And I should say, you know, we know that there's risk from these sprays. Sure. You know, we know the pesticides used are broadly toxic and are applied in an indiscriminate manner. You know, there has been a little bit of research done on barrier spray toxicity to beneficial insects. You know, there was one that found monarch caterpillars that were fed leaves treated by a barrier spray had much lower survival rates than control caterpillars. But, you know, we didn't have a good way of kind of, yeah, letting our Sources members and other members of the public know who reach out to us. How much of a risk is there from these sprays? Big time. And this is so important to put into context of having those data. It's one thing to walk around and get a general sense that, yeah, spraying insect poison all over is probably going to be bad for a lot of insects. But vibes only get us so far. They're great for Internet memes. They're great for content production. But when it comes to changing policy, when it comes to changing minds, I mean, show me the data. Right. And that's where I think it's so important to go into these assumptions that we have, oftentimes very well informed assumptions, but assumptions nevertheless, and ask those questions and get data to support or refute hypotheses. A hundred percent. I think that's a great way to put it. You know, it's really important, I think, when we're making recommendations to have, you know, something to really support those. So how do you go about studying this? Because I would imagine the pesticide companies aren't too keen on getting involved with this. And I would imagine, too, not everyone you're knocking on doors wants to be a study site. So what did this look like from a scientific perspective? Yeah, great question. So as a quick summary of the experiment, we recruited volunteers who have a neighbor who hires one of those backyard mosquito spray services so that we could sample their nearby or adjacent yard. And while recruiting for volunteers, we unexpectedly found four volunteers who actually hire one of those services. So we got to include those as a data point as well, which wasn't our intent, but was honestly really exciting to kind of get that site level data as well and gave us a little bit more information for the study. And we also found people who received a vector control district spray in their yards because that's a similar question. What are the impacts of those sprays on yards? And yeah, going back to what you were saying, I think in a very ideal controlled world, we would have these monitoring devices set up at different distances and spray pesticides ourselves, which sounds weird to say. So maybe that's not an ideal world. It's good that we didn't spray pesticides for this. But we were opportunistic. So we wanted to find places that have a lot of mosquito spraying going on. We also needed partners to reach potential volunteers. So we recruited volunteers in Massachusetts through my colleague, Rosemary Malfi, who used to manage the Massachusetts Pollinator Network. So she had a lot of connections. So we contacted people she knew and we just tried to come up with a list of potential volunteers and said, you know, hey, do you we had an online survey to ask them questions, ask whether they hire a spray service. If their neighbor does, if so, do they know what the schedule is and did they feel confident putting our monitoring device out? We also worked with Decatur, Georgia, because they're a B-City USA affiliate. So through the B-City USA network, we were able to reach potential volunteers there. And then finally, we chose Iowa. We partnered with Good Neighbor Iowa to use their volunteer network as well. So we just tried to cast a wide net of potential volunteers, ended up having 26 sites overall in the end. And what we did was we used silicone bands as monitors instead of sampling vegetation. We've done a series of previous Xerces pesticide sampling studies. And in the past, we've sampled vegetation, looking at pesticide residue on milkweeds in the Central Valley, milkweeds in nurseries. A lot of cool research. But, you know, when we were thinking about sampling vegetation in a yard, we realized it would be impossible to sample, you know, leaves from vegetation at similar distances from where sprays were occurring. And then also different leaves might have different characteristics that might also change how these sprays adhere to them. You could think like a waxy magnolia leaf versus like a fuzzy lambs ear covered in trichomes. Like those might be different, you know, so we wanted something that was a little bit more controlled, both as far as where we're placing it, but then also, you know, this kind of constant surface. And the silicone bands are really great because they can sample all sorts of chemicals. And they first started being used in kind of more human and environmental toxicology, like having firefighters or roofers wear them for a week to see what types of chemicals they're exposed to. But recently, they've been being used more and more in pesticide monitoring and ecological studies. And yeah, we mailed them to volunteers that could place them consistently in the same location in their yard before a spray event. And then quickly pull them from the yard, wrap them in tinfoil, put them in plastic bags, store them in the freezer before we had them analyzed at the lab. So that was kind of the quick rundown of how we did this experiment. That is really cool. And this is why I will always advocate for science for science sake. You never know where that new technique is going to teach you something or give you an insight that you wouldn't have otherwise. But you know it so cool what you can learn from other forms of science to apply to your own world of science But at the same time the fact that people wanted to get involved is also very exciting I can understand this as a neighbor who as a neighbor that likes to fog for mosquitoes I don't think they're bad people. I just have to figure out how to have that conversation and say, hey, why are you doing that? But I'm really curious, actually, about the handful of people that pay for that service. What was their reasoning for wanting to get involved? Is it typical of like, oh, well, hey, I didn't know this was bad. Let's figure out what's going on. Yeah, that's a really good question. So I didn't interrogate that with the volunteers and kind of talk through why they were making those choices. But I think this is just a really great example of how pervasive the kind of pesticide messaging is and how normalized the use of pesticides is. just because people that were reaching through these organizations and outlets that were, you know, very kind of ecologically minded, environmentally minded. Some of those people were still using these spray services. And I think it just kind of is a testament to how successful some of that marketing is for mosquito spray services and how often people think, hey, this is only going to kill mosquitoes. It's not going to put everything else at risk. So I think it's probably just a good example of, unfortunately, we kind of face it all the time when we're working with people. I mean, how good of a marketing scheme it is from the pesticide standpoint of putting one of the most pernicious and invasive parasitic organisms that spreads umpteen amounts of disease across the globe in the crosshairs of your marketing campaign. I'm not saying it's always malicious, but you kind of got a built in like, yeah, who would want to support these things? But I also think at the end of the day, invasive mosquito or not, you know, the hubris of saying, well, if we got rid of them, the world would be a better place. I mean, think about how many things eat mosquito larva and male mosquitoes do pollinate. I'm not advocating for them as disease vectors, but they are part of this ecosystem. Granted, the invasive ones aren't. But if they're not just killing the invasive ones, then we've got a bigger problem on our hands. Yeah, no. And that is something that, you know, I do mention sometimes kind of an outreach that, you know, they're they do play roles in the ecosystem. You know that like you mentioned, they're they're the larvae are food for all sorts of organisms. They're part of nutrient cycling from wetland areas to more upland areas as, you know, the adults hatch and fly to, you know, kind of out of the water that they were produced in that dry land. And yeah, in some places like the Arctic, there's millions of pounds of mosquitoes that hatch every year and are food for lots of migratory birds and things like that. So yeah, they definitely play ecological roles. And yeah, they also pollinate in some cases, as you're mentioning. Yeah. And so what did you end up finding with this work? I mean, obviously, there's a lot of nuance to it, but there's also very important results that come out the other end when you do have a lot of sites that are as, you know, like you said, as wide of a net you could cast. Yeah, no, thanks for asking. Great question. So overall, we found on these bands, we found the residue of 12 different insecticides. We also found eight fungicides. They were all in Iowa. We didn't do anything with the fungicides because this wasn't, you know, presumably these weren't from mosquito sprays, but it kind of an interesting observation that we did pick up, you know, some other chemical signatures. And then we also found a synergist, a hyperonial butoxide, which is added to mosquito sprays and all other types of insecticide applications as well to actually increase the toxicity of the pyrethroids. And five of these insecticides were pyrethroids. And we found the pyrethroid bifenthrin in 76% of the non-control samples. So it was super widely found across the landscape, across all three states, across yards that were sprayed for mosquitoes versus vector control district sprays. And then we also found three insect growth regulators as well, which are, I think, sometimes added to try to control some of the immature mosquitoes. And we also found two neonicotinoids, which are highly toxic. We found these at smaller levels, whether they were just present in the landscape, if they were in tanks, you know, just residue were in the application tanks, or if they were part of this application, it's hard to say, but it's good to note that we did find those as well. Yeah. I mean, just from a sampling perspective, that is fascinating and really sobering. But when you think about how that stuff got onto the bands, the silicone bands in the first place, it's being sprayed into the air, it's landing on a variety of surfaces. And you've already hinted at, like if it's on a leaf, anything that lands on that leaf is exposed to it. Anything that eats that leaf is exposed to it. If it lands on a flower, oh, gosh, the amount of life that is interacting with is alarming. Yeah, Matt, that's such a good point. And I think that's something important to think about is that, you know, these some of these pyrethroids have decently long half lives. You know, the amount of time it takes for half the compound to break down. And since these companies say, hey, this spray is good for three weeks and you think about a plant being covered, you think about all the insects that are walking over this plant. You think about things like butterfly caterpillars that are feeding on it and aren't very mobile. They're probably just stuck on that one plant that's treated. That exposure risk through ingestion of the food is going to be really high. Yeah, it's just really concerning. Big time. And when you hear about this, you start putting this insect decline on a global scale into perspective. And you go, it's no wonder anything's alive in some of these areas. It's just it's a pretty darn toxic landscape out there in some places. And, you know, you expand that out. It's not just the insects we have to think of. It's getting into waterways. It's washing off, going into our drinking water, let alone the fish that we eat or the vegetables that we eat or just our exposure. I mean, the people I'm discussing have a child that plays in the yard all the time, you know. Great to see her outside. But what is she touching that's persistent out there? I think that that's such a good point. And that's something that, you know, all sorts of other research has been finding. Our own Sources Research has been finding where we're just finding these patterns of pervasive background contamination throughout our landscapes, whether you're sampling pollinator plants, whether you're sampling soil, whether you're sampling waterways. You know, the USGS has a lot of great water sampling data and they find all sorts of pesticides washing off into our into our waterways. and I think it's a great thing to think about when it comes to pesticide reduction that what we do in our yards or on a single site matters of course but pesticides don't stay in one place they drift they wash off they move across the landscape and put you know these other areas at risk as well big time one of the things we were also interested in is trying to figure out What does this mean to an insect? So we found, as I mentioned, we found 12 different insecticides. We found an average of four compounds per yard that was sprayed just over one compound per yard that experienced neighbor drift. About two compounds in a yard that was sprayed by a mosquito control district. And we had I can read this number. I have it in my notes here. We had over 1,500 nanograms per gram of band in sprayed yards, 28.6 in neighbor yards and 7.3 in mosquito control district sprayed yards. So that's really hard to put into context. What it tells us is that sprayed yards had by far the most insecticide residue. But we did want to try to figure out what these numbers mean in a real world sense, because then it's easier to communicate with people. Hey, this is what is kind of at risk here, even though, of course, and we can talk about this. but you know these less than lethal amounts are also concerning for other reasons you know amounts that uh don't necessarily kill an insect but might make them sick might make them uh less able to navigate things like that are also concerning um but for figuring out what this means in a real world sense it was kind of difficult because it's hard to get from the amount of pesticide on a silicone band to what would be a bee um but so we use the non-native honeybee as our model organism because unfortunately pesticide toxicity isn't known for most of our native bee species or native insect species in general. And as kind of an aside, that's a huge data gap and a challenge with doing this work is how most pesticides impact most of our native pollinator species isn't known. So we have to rely on proxy species like the honeybee, which is used in the regulatory testing, even though our native species are often more sensitive. Right. Well, but yeah, we did some math, figured out how much of a bee would be sprayed by looking at some papers, looked at surface area, did some calculations. And our estimate is that yards that were directly sprayed by barrier spray surfaces had on average over six and a half times the amount of pyrethroids that would be toxic to honeybees. So the LD50, the amount that would kill 50 percent of a test population in the lab. And the yards with the highest values were over 34 times and 24 times that lethal dose, which is pretty astounding. And moving on to yards with neighbor drift, they had a much lower on average 0.12, so about 12% of that lethal dose. But the highest level in a neighbor drift yard was two times that lethal dose. So that potential for acute lethality is really there in those neighbor drift yards potentially. Um, so yeah, so that kind of puts it in context and I guess how do you kind of message this? I think, yeah, including some of that information, trying to kind of say, hey, this is what's at risk when these sprays are sprayed. It's not just going to kill mosquitoes, but other organisms that do so much for us and for the environment are also potentially going to be killed or made sick from these applications. Um, it's a, yeah, it's kind of a first start. Wow. That is, that's a gut punch. um that hurts to hear because it does put into this context how you know even things you're doing in your own yard this is my property kind of thing it doesn't stop there in these situations and you think of like different ways of it like the whole don't tread on me thing it really resonates here because it's a yeah you're you're forcing your trying to control nature onto my yard where i am trying my best to not do that and being less aggressive about it in many contexts like yeah some of my seeds might blow over there but my gosh man that that really sucks yeah no it's not not a great yeah not a great thing yeah yeah and i mean just to repeat what i said before it's a miracle anything's alive out there when you think no it's it's really astounding honestly yeah especially in some you know neighborhoods where there might just be really high levels of kind of these conventional manicured lawns conventional pest management um And yeah, just kind of a reminder that just because you have a green space in an urban area doesn't mean it's habitat. Right, right. Yeah. And when you think about what you said there in the data gaps, that's the part that is an additional alarm to me because this is so often the case with so many different organisms out there. And it's a logistical issue, right? Like we can't study everything to the nth degree. There's not enough time and resources to do that. But the amount we don't know and we're just kind of winging it on the other end is also terrifying, because even if you take that as a conservative estimate based on a well-studied agricultural organism like the honeybee, both sides of that bell curve suck. Yeah, it's a lot of pesticides, no matter how you cut it. Yeah, exactly. And I think, yeah, your point is super well taken. And like, you know, in the defense of the EPA, it's there's no way you can screen every single organism for all of these different chemicals and also chemical compounds. Didn't even talk about that or combinations, I should say, compounds, because sometimes, you know, almost all the time when we're sampling, we're finding mixtures of chemicals. And often we don't know how those are interacting together. Like logistically, it's a very difficult thing, but it would be great. Yeah, if we had more insight to some of these native species and, you know, a broader range of taxa as well. Some Lepidoptera, things like that on, you know, the impact of some of these really commonly used pesticides across our landscapes. Yeah. And I think a big message here, again, is this idea that it's not selective. It's not just the mosquitoes, which, again, I can get my head wrapped around trying to take out invasive mosquitoes that could be carrying dengue or, you know, you name it kind of viruses. But, you know, some of these people equally care about the pollinators, equally care about the beneficial insects that are also being harmed by this. And I think kind of telling those stories, you get a lot more people going. And I'm not saying this is you're not doing this, but I think those kinds of stories turn the light bulbs on at least a fraction of those people's heads like, oh, wait, it's not selective. what? Yeah, 100%. Yeah, I think that that's a really great message to share. And then just, yeah, trying to get the word out through outreach. We're trying to come up with some new fact sheets and things that people can hand out at tabling events that these city affiliates can hand out throughout their communities. I'm just trying to do more talks on this issue. And I think there has been a lot of interest and people are concerned. But then I think the next thing is just, Yeah, trying to get the word out there that you were saying. These are broadly toxic and aren't going to just kill mosquitoes. You know I mentioned Decatur They a Bee City affiliate We did sampling there They have a really great grassroots campaign They come up with these fantastic Mosquito Spraying Kills Bees yard signs that kind of almost are analogous to the ones that mosquito spray companies often put in yards to say, you know, it was sprayed by X company. So you can put those in your yard. It's kind of a way that you do outreach in the community. They've done a really fantastic job there. I think, yeah, it's a challenge to kind of get the word out because when you Google mosquito sprays or mosquito controls, all of the top things that are going to pop up on your Google search are a lot of these companies and the marketing from them. So it can be a really challenging thing to kind of compete against. But we're definitely trying our best. Yeah. Yeah. And that's a good jumping off point there for like, where do you go with this? Because you're not the traditional academic model. It's not, OK, well, we've done this. Let's move on to the next thing. Like you're you're an organization with a lot of different hats doing a lot of different things. Like when you find results like this, what are the next steps? Like, do you continue doing more narrowing the research, broadening it? Like, what does that look like? Yeah, that's a really good question. So I would say that this research is, you know, answering a question that we had or trying to, you know, at least giving an insight into into, you know, this question that we get a lot from our Xerces members. but kind of fit into this broader context of these other studies that we've done looking at pesticide risks in landscapes. And more recently, some of our studies are looking at urban landscapes in particular, because the risks of pesticides to pollinators in urban landscapes isn't super well studied. So it's definitely one of those things as we're recommending people to create habitat in their towns and cities, we want to make sure we're understanding what the potential risks are there. So we can try to mitigate them when we're making recommendations. We understand what's out there. So I think this research is part of that kind of broader body that we're trying to kind of put together. But we do all sorts of outreach across the organization. We have our Bee City affiliates, as I mentioned, which at this point we have well over 350, I believe, different communities and campuses that are part of this program. And as I mentioned, pesticide reduction is one of the things that they commit to. We have habitat kits where people apply to get a habitat kit, which is plants and instructions. And we have habitat kits in the Northeast, in California, Pacific Northwest. I'm probably missing other places too, but we have people who are doing, you know, creating habitat through these kits. We have, we're doing work boosting our information for HOAs. And then we also have our Bring Back the Pollinators program. It's a campaign where people can sign a pledge. And we're actually just relaunching the program in a couple of weeks in February. And we're trying to increase engagement and build community around the program. So we're going to have our webinars this year, the Bring Back the Pollinators themed. We're going to have Bring Back the Pollinators Q&A sessions every quarter, quarterly newsletter. And the whole program is just based off of, there's four basic principles to bring back the pollinators. It's just provide flowers, provide nesting and overwintering sites, avoid pesticide use and spread the word. So the reason I bring up all of these different programs is we're doing all of this outreach. And when we learn something new, like doing this study, we try to imbue our findings and the new recommendations through all of that outreach. So so then that to kind of answer your question, that's the next step. So it's like, great, we found something new that's going to help us better conserve and protect pollinators. And then we try to look to see where we can we can make it actionable and make sure we're spreading the word to our Xerxes community, our Xerxes members, all the people we reach doing our outreach. So but that's a really good question. It's it's. Yeah. How do you translate these findings to actually like on the ground action? Right, right. I mean, that's incredible. And I'm sure that was just the tip of the iceberg, right? It's incredible what Xerxes is putting out there. But in terms of that meeting people where they're at question, I'm sure the next one is usually, so what do I do to help at least mitigate some of the impacts of mosquitoes in my landscape? Like, I'm not going to pretend again that I'm not annoyed to the nth degree when the tiger mosquitoes come out. So what can people do that isn't as deadly to everything else in the process? That is a really great question. So so and I do want to stress that through all of this talking about the risk of mosquito sprays and their impacts. I don't want I know very cognizant that there are can be real disease risks with mosquitoes and not trying to under under sell that. And I understand the need to control disease carrying mosquitoes in certain contexts. But one of the things that we definitely tried to message is that there are more ecologically friendly, more effective long term ways to do this than just spraying for mosquitoes that won't put other organisms at risk. And number one, it's very simple, but it's just removing standing water source reduction. You'll hear people say it. Mosquitoes need standing water to reproduce. Adults lay their eggs in still water and they need just the amount that's in a bottle cap. So not very much. And, you know, one mosquito can lay hundreds of eggs in her lifetime. And the whole process of egg laying to the larva feeding on microorganisms in the water to pupating and flying off as an adult. It depends on the species, but it's generally eight to 10 days. So that means water that stands around for just over a week can lead to a population explosion. So, again, it sounds simple, but we just tell everybody to look for places where water might be pooling, dump water from buckets, trash cans. Clogged gutters can be a really kind of sneaky hidden source of standing water. And then if you have bird vads or pet bowls, just making sure you're dumping them and refilling them weekly to prevent any mosquito larva from completing their life cycle. if you have a permanent water body or like a little backyard pond for example if the water's still you can add a little fountain or water feature of some sort just to keep that water moving or even just like a little pump that kind of circulates the water a bit because that's going to make that water inhospitable for mosquitoes to reproduce yeah and then there's obviously the personal protection aspect as well you know wearing long sleeves not going outside when mosquitoes are most active. And then also they're not super strong flyers. So if you want to use your patio in the evening and you're having mosquito issues, just a simple fan is enough to keep mosquitoes from landing on you and biting you. So those are all kind of common sense ways that as an individual, you can reduce mosquito populations in your yard and the risk of being bitten. But I also think it's important to remember that mosquitoes are most effectively managed at the community level. So we do have some resources on how to help your community create an effective mosquito management plan if they don't already have one. I think there's a lot of vector control districts that do really great work. There's others that might be lacking more in some ways. So a really good one will actually be monitoring for larval mosquito populations and also disease prevalence. And then they'll only spray for adults when certain thresholds are met. So they're kind of doing this integrated pest management framework, essentially. You know, if, you know, are the mosquitoes that vector disease even present at high levels? You know, are the diseases themselves present? You know, if there's high populations of other mosquito species, that might be, you know, a big nuisance. Nobody likes to get bit, but it's not a disease risk so it wouldn't warrant you know these right you know chemical you know sprays uh uh so yeah and then also a good you know kind of community level program involves outreach and education so that people know yeah this is what i can do to stay safe uh this is how i can reduce mosquito populations in my yard if everybody together is working to to reduce standing water and things like that all of these efforts are going to be a lot more effective than you know just one person And, you know, doing great work, reducing water. But then if all the mosquitoes from the surrounding yards are just flying in, it's obviously not going to be as effective. I look at the in-between neighbor and his pile of tires. Yeah, exactly. Because the pile of tires is a great place for a lot of standing water, for sure. Yeah, and thinking about, you know, the more holistic approach, you look at these retention ponds. You just said stagnant water is a big part of that. when you mess with hydrology, when you mess with wetlands, when you're creating these retention areas that aren't necessarily well-maintained or have good flow, it's a bigger, like you said, it's a community issue that can be this is the impact that messing with ecology and biodiversity can have on the human system. We love it in some ways, but when it starts to bite back quite literally, there are consequences for these actions. And thinking about the different ways your community is going about that, that's why getting involved at different levels of this. You don't necessarily have to be an ecologist to get involved. You can be a city planner, a map maker, you know, someone that can really apply skills in different ways to think about these problems. Yeah, I think that's a really fantastic way to look at it. You don't have to be an ecologist, you know, epidemiologist, you know, working to solve these problems. There's a lot of different ways that you can kind of help, you know, contribute to the success in your community. Totally. And one great way, or a good place to start, I should say, is to look at Xerces website and all of the great resources that you started to name, but they're, again, so much more. Where do you recommend people go looking to find out more about this and everything else going on in the world of invertebrate conservation at Xerces Society? Great question. Yeah. So you can go to our Xerces library at xerces.org. At our Xerces library, we have all sorts of publications, fact sheets, and handouts, things from polyandre plant selection to pesticide reduction to endangered species conservation, how to create nesting and overwintering sites, all sorts of information, you know, directly related to what we talked about on the podcast here to just general and bird root conservation in general. And this library is really, you know, decades of work. It's free, has great resources. So I really encourage you to, yeah, go check it out. There should be a kind of a search bar inside and you can search by topics. You can search for pesticides, mosquitoes, pollinator conservation, pollinator habitat. And yeah, I encourage you to kind of dig in there. We also have some books as well that you can find wherever you get your books, bookstores or libraries as well that are also great resources if you want kind of a slightly meatier thing to dig into. Excellent. Yeah. I mean, this is this is the actionable items, right? All of us are into plants for one reason or another, but one thing that unites so many of the plant folk is that love of their role in ecology. It all starts with that, and gardening is our way of doing that in so many instances. And so if we can be better gardeners through the knowledge that places like Xerxes gains and gives out so willingly for free in so many instances, we're doing better for the planet as a whole and our communities and the people that rely on them. So, Dr. Anderson, I appreciate all of the effort you and your colleagues are doing to understand and protect invertebrates, you know, throughout the world of all different shapes and sizes. They're all important. But thank you so much tonight for taking the time to talk to us about it. Yeah, well, thanks so much for having me on. And yeah, it's fun to listen to your podcast as well and learn so much about the world of plants as well, I have to say. Appreciate that. So, yeah, and it's great to think about doing ecology. It's fun how everything intersects, plants, pollinators. I have kind of come at this more from an insect pollinator perspective, but now I'm slowly becoming more of a plant nerd because I'm so into selecting native pollinator plants. We got another one. It's a fun world to dive into. Yeah, it's awesome. Hey, ecology means you're never bored. Exactly. That's the best part about this field. So, but yeah, I appreciate it. You are welcome back on anytime. So as things develop, as you learn more, as you develop more resources, please keep in touch. I'd love to talk about it. Definitely. Yeah, I'd be happy to. All right. You take care. All right. You as well. All right. Phenomenal work. I can't thank Dr. Anderson enough for taking time out of his busy schedule to not only talk to us about this, but for doing the research in the first place. And of course, please go check the show notes over at indefenseofplants.com because that is where I put all of the links so that you can learn more. And as we discussed throughout this entire episode, there's a lot of actionable items that are available at Xerces website for free. Once again, all of those are in the show notes over at indefenseofplants.com. But also consider supporting the show because I can't keep having conversations like this unless you support the podcast. There are so many great ways to do that. As I mentioned at the beginning, we have a Patreon where you can get access to an entirely separate podcast about the trials and tribulations of learning how to garden better. Who wouldn't want to get involved in that conversation? And the only way to be part of it is to become a patron over at Patreon.com slash InDefense of Plants. Speaking of patrons, I have a shout out to the latest producers on this podcast. A big, big thank you goes out to Neil, Matthew, April, and Dana. All of them have signed up at the producer credit level. So they are maximizing their support of this podcast over at Patreon and getting an entirely separate podcast and a few other kickbacks in the process. So thank you to them and everyone that supports the show that way. We also have copies of my book and customizable merch for sale. And all of those links are in the show notes as well. At the very least, make sure you hit that subscribe button and keep checking back in. But that is it for this week. I thank you all for listening. Until next time, hang in there, stay healthy, and get outside if you can. This is your host, Matt, signing out. Adios, everyone.