1 00:00:00,020 --> 00:00:03,020 Dan Suiter: Dr. Michael Scharf: Welcome again, everyone. 2 00:00:04,730 --> 00:00:07,000 Dan Suiter: Dr. Michael Scharf is the O.W. 3 00:00:07,320 --> 00:00:13,620 Dan Suiter: Rawlins Orkin Endowed Chair in Urban Entomology and Molecular Physiology at Purdue University. 4 00:00:14,660 --> 00:00:21,060 Dan Suiter: He entered Purdue in 1986 as a freshman in agriculture and subsequently earned his BS, 5 00:00:21,630 --> 00:00:27,720 Dan Suiter: MS, and PhD degrees from Purdue University in 1991, 1993, and 1997. 6 00:00:28,760 --> 00:00:35,020 Dan Suiter: After graduation, Dr. Scharf spent time at the University of Nebraska and Cornell University 7 00:00:35,570 --> 00:00:39,840 Dan Suiter: as a postdoc in the University of Florida where he was a tenured professor for several years. 8 00:00:40,750 --> 00:00:49,300 Dan Suiter: In 2010, Mike returned to Purdue and his primary research interests at Purdue 9 00:00:50,199 --> 00:00:53,800 Dan Suiter: relate to understanding biochemical and physiological mechanisms 10 00:00:54,140 --> 00:00:58,760 Dan Suiter: insects that have practical implications for pest management. Welcome Dr. Scharf, the floor is yours. 11 00:00:59,620 --> 00:01:11,920 Mike Scharf: Thank you very much, Dan. It's really nice to be here today and I definitely appreciate the invite to share some of this information with the urban pest management industry. 12 00:01:12,700 --> 00:01:21,620 Mike Scharf: So today I'll be talking about just some of the basics of insecticide classification and mode of action for pest management professionals. 13 00:01:21,980 --> 00:01:30,260 Mike Scharf: And I'll acknowledge right at the outset that this is probably not something that's on everybody's radar screen out there in the industry. 14 00:01:30,600 --> 00:01:37,760 Mike Scharf: And just one of my goals in this presentation is just to help, even if no matter what your experience level is with pesticides, 15 00:01:38,660 --> 00:01:43,560 Mike Scharf: just to help raise anyone's level of understanding for how these things work. 16 00:01:45,300 --> 00:01:51,680 Mike Scharf: So my goal in this presentation is just to, you know, just this one overarching goal 17 00:01:52,350 --> 00:01:56,140 Mike Scharf: and that's to improve general knowledge of how insecticides work. 18 00:01:57,060 --> 00:02:03,780 Mike Scharf: So, if you're dealing with a product, you can ask yourself, does this product target 19 00:02:03,799 --> 00:02:05,340 Mike Scharf: the nervous system of the insect? 20 00:02:05,619 --> 00:02:08,119 Mike Scharf: And if so, in what way does it target it? 21 00:02:08,599 --> 00:02:11,039 Mike Scharf: Just maybe you can try to understand that a little better. 22 00:02:12,380 --> 00:02:16,819 Mike Scharf: Or does the product work in a completely different way like an insect growth regulator? 23 00:02:17,080 --> 00:02:21,180 Mike Scharf: So that would be very different than an insecticide that would target the nervous system. 24 00:02:21,780 --> 00:02:26,020 Mike Scharf: These are things I'll get into in a little more depth as I go through this talk. 25 00:02:27,570 --> 00:02:34,620 Mike Scharf: And so, but knowing how these insecticide tools that we have available, how they actually work, 26 00:02:35,480 --> 00:02:37,480 Mike Scharf: this is essential knowledge for the industry. 27 00:02:38,870 --> 00:02:39,980 Mike Scharf: And so why is that? 28 00:02:42,400 --> 00:02:48,440 Mike Scharf: And so here's just a list of things and these are themes that will come back through the 29 00:02:48,600 --> 00:02:53,720 Mike Scharf: talk but just to kind of introduce them here and then they'll be reinforced later. 30 00:02:54,950 --> 00:02:57,520 Mike Scharf: The first is just safety. 31 00:02:57,940 --> 00:03:06,100 Mike Scharf: So, you know, some insecticide modes of action have lower non-target toxicity than others. 32 00:03:06,540 --> 00:03:09,700 Mike Scharf: So they affect insects more than they do mammals. 33 00:03:10,120 --> 00:03:11,260 Mike Scharf: You know, humans are mammals. 34 00:03:11,700 --> 00:03:13,700 Mike Scharf: And so there's the safety factor. 35 00:03:16,880 --> 00:03:21,660 Mike Scharf: Understanding how insecticides work can help with interpretation of advertising and trade 36 00:03:21,840 --> 00:03:28,440 Mike Scharf: literature which isn't always technically accurate so it's good to have a little extra 37 00:03:28,620 --> 00:03:30,780 Mike Scharf: knowledge so you can interpret that trade literature. 38 00:03:32,220 --> 00:03:35,680 Mike Scharf: pollinator health is really huge right now. 39 00:03:35,959 --> 00:03:41,680 Mike Scharf: You know, it's becoming something that we all need to know about in the industry and how to protect pollinators. 40 00:03:42,260 --> 00:03:48,700 Mike Scharf: Especially with products like nicotinoids that actually, you know, they move around in plants. 41 00:03:48,940 --> 00:03:56,720 Mike Scharf: And so if you're doing a lawn application, for example, you know, the plants, flowering plants in the yard or the landscape 42 00:03:56,959 --> 00:04:00,120 Mike Scharf: can take up those nicotinoids and that can affect pollinators. 43 00:04:01,780 --> 00:04:04,260 Mike Scharf: Resistance management is a really big factor. 44 00:04:05,420 --> 00:04:11,680 Mike Scharf: Knowing how to rotate products is really important and do other things that can help 45 00:04:13,280 --> 00:04:14,820 Mike Scharf: get around the resistance problem. 46 00:04:16,980 --> 00:04:27,040 Mike Scharf: Product sustainability. In the industry we're stewards of, we represent the manufacturers as well as the pest management industry. 47 00:04:27,310 --> 00:04:33,520 Mike Scharf: And you need to understand that every product, every insecticide product that makes it to the market, 48 00:04:34,030 --> 00:04:38,920 Mike Scharf: it costs hundreds of millions of dollars, if not more, billions of dollars to get to the market. 49 00:04:39,240 --> 00:04:48,280 Mike Scharf: And so, you know, using products wisely so they have the longest market life is just, it's good business sense for the whole industry. 50 00:04:50,340 --> 00:04:56,380 Mike Scharf: Understanding how insecticides work can help design customized pesticide applications for, you know, 51 00:04:58,139 --> 00:05:00,819 Mike Scharf: And that goes along with situational pest management. 52 00:05:00,990 --> 00:05:06,580 Mike Scharf: So designing customized applications with the right products for the right situation. 53 00:05:06,990 --> 00:05:12,500 Mike Scharf: So understanding how insecticides work and how they're formulated really comes into play 54 00:05:12,860 --> 00:05:14,900 Mike Scharf: with situational pest management. 55 00:05:15,620 --> 00:05:35,060 Mike Scharf: And then the last one here is just communicating with your customers and explaining to them how products work, but being able to do it in a way that communicates competence that shows that you really understand what you're doing, you're going to be safe, you're going to protect pollinators, etc., etc. 56 00:05:35,860 --> 00:05:40,860 Mike Scharf: And so, you know, all these things are really important, I feel, and they all go together. 57 00:05:41,040 --> 00:05:46,840 Mike Scharf: And that's my motivation for putting together this particular talk that I'm going to be giving 58 00:05:47,080 --> 00:05:51,640 Mike Scharf: here, which I've given now several times over the last five years. 59 00:05:52,660 --> 00:05:58,340 Mike Scharf: And despite the technical nature of the information, I do get a lot of positive feedback on it. 60 00:05:58,420 --> 00:06:01,500 Mike Scharf: So hopefully everyone will feel the same today. 61 00:06:03,940 --> 00:06:07,040 Mike Scharf: So here's an outline of what I'll be presenting. 62 00:06:08,500 --> 00:06:13,960 Mike Scharf: I'll just get in some, I just covered some background and introductory information. 63 00:06:15,560 --> 00:06:21,440 Mike Scharf: If we want to know how insecticides work, we need to talk about some of the basics of insect physiology 64 00:06:21,850 --> 00:06:23,520 Mike Scharf: because that's how insecticides work. 65 00:06:23,720 --> 00:06:28,700 Mike Scharf: They disrupt the physiological function of the organism that they're targeting. 66 00:06:29,120 --> 00:06:35,700 Mike Scharf: And that's how they work. That's how they cause deleterious effects in those target organisms. 67 00:06:37,560 --> 00:06:43,760 Mike Scharf: I'll talk about some basics of insecticides and the modes of action and then talk about 68 00:06:44,860 --> 00:06:51,900 Mike Scharf: break them up into two different groups: the neurotoxic insecticides and then the non-neurotoxic insecticides. 69 00:06:52,860 --> 00:06:57,000 Mike Scharf: And then I'll finish with some more of this practical knowledge like the situational pest 70 00:06:57,360 --> 00:06:59,180 Mike Scharf: management kind of information. 71 00:06:59,759 --> 00:07:05,139 Mike Scharf: So kind of bringing things, concepts together and talking about factors that affect how well 72 00:07:05,840 --> 00:07:06,780 Mike Scharf: insecticides work. 73 00:07:13,540 --> 00:07:20,840 Mike Scharf: So even if you don't follow along with everything in excruciating detail and it's all very new 74 00:07:20,840 --> 00:07:26,060 Mike Scharf: to you, the information that I'm presenting today, there are two additional sources of 75 00:07:26,360 --> 00:07:26,680 Mike Scharf: information. 76 00:07:27,500 --> 00:07:35,960 Mike Scharf: And the first is an article published in 2011 called Insecticide Primer and Insecticide Mode of Action. 77 00:07:35,970 --> 00:07:37,940 Mike Scharf: This appeared in PCT Magazine. 78 00:07:38,730 --> 00:07:40,780 Mike Scharf: This was authored by myself and Dan Suiter. 79 00:07:42,600 --> 00:07:47,220 Mike Scharf: So there's some good supporting information to what I'll be presenting today. 80 00:07:47,850 --> 00:07:55,680 Mike Scharf: And then over here on the right there's this publication that probably Dan and I, we co-authored that we probably need to revise it soon. 81 00:07:56,319 --> 00:08:00,419 Mike Scharf: almost 10 years old now, Insecticide Basics for the Pest Management Professional. 82 00:08:01,280 --> 00:08:07,220 Mike Scharf: And this is available free of charge at this website shown at the bottom, sponsored by 83 00:08:07,220 --> 00:08:08,139 Mike Scharf: the University of Georgia. 84 00:08:08,900 --> 00:08:14,960 Mike Scharf: And I'll put these up at the end too in case you don't have time to write down this information 85 00:08:15,520 --> 00:08:15,659 Mike Scharf: here. 86 00:08:16,270 --> 00:08:22,060 Mike Scharf: So there's additional information out there that will perfectly go along with the information 87 00:08:22,180 --> 00:08:23,159 Mike Scharf: I'm presenting here today. 88 00:08:26,379 --> 00:08:31,720 Mike Scharf: So, starting with insect physiology and just giving a really brief overview. 89 00:08:33,209 --> 00:08:37,620 Mike Scharf: So, if you were an entomology student like we have here in our department at Purdue University, 90 00:08:38,029 --> 00:08:42,740 Mike Scharf: so you would take a whole semester course on insect physiology and biochemistry. 91 00:08:43,840 --> 00:08:50,760 Mike Scharf: I'm not going to cover that whole course today, but I've just compressed it down into a couple of slides here. 92 00:08:51,960 --> 00:08:57,260 Mike Scharf: And there are just some critical physiological components of insects that is good to know about. 93 00:08:58,560 --> 00:09:04,860 Mike Scharf: And I'll explain why here in the coming slides, but these are the cuticle, you know, the outer covering of the insect. 94 00:09:05,280 --> 00:09:10,880 Mike Scharf: The nervous system, which is basically what controls what's going on in the insects. 95 00:09:12,730 --> 00:09:19,220 Mike Scharf: The same thing happens in mammals and any animal has a nervous system that controls what's going on in the body. 96 00:09:20,600 --> 00:09:26,300 Mike Scharf: Muscles, of course, control movement and those muscles are controlled by the nervous system. 97 00:09:26,820 --> 00:09:34,560 Mike Scharf: The digestive system is, you know, that's where things happen, you know, with nutrition 98 00:09:34,980 --> 00:09:41,680 Mike Scharf: and food that's ingested in the insect and there's this really important idea that, you 99 00:09:41,680 --> 00:09:46,500 Mike Scharf: know, the inside of the digestive tract is actually the outside of an organism. 100 00:09:46,779 --> 00:09:48,480 Mike Scharf: So it's kind of like we have this 101 00:09:49,440 --> 00:09:54,279 Mike Scharf: tube going down the middle of us that's actually outside of our bodies, which is 102 00:09:54,380 --> 00:09:59,259 Mike Scharf: and that's a barrier to digested insecticides. 103 00:10:00,540 --> 00:10:04,500 Mike Scharf: We talk about that too and the respiratory system is really important as well. 104 00:10:05,420 --> 00:10:09,160 Mike Scharf: You know what we're talking about, for example, fumigant insecticides, right? 105 00:10:09,339 --> 00:10:13,339 Mike Scharf: That's how fumigants actually make it into the insect through the respiratory system. 106 00:10:15,820 --> 00:10:23,580 Mike Scharf: So just talking about some of these features in more detail, so I've just shown them here, just kind of run through them one by one. 107 00:10:24,000 --> 00:10:30,560 Mike Scharf: First is the nervous system, and so in every insect, you know, they have the nervous system runs along there. 108 00:10:30,570 --> 00:10:37,500 Mike Scharf: They have a brain and there's a ganglion that controls their mouth parts and then this ventral nerve cord that runs along 109 00:10:37,800 --> 00:10:46,760 Mike Scharf: the ventral, the bottom side of their body. That's the central nervous system of the insect and then there are all these peripheral nerves that come out and go throughout the body. 110 00:10:47,380 --> 00:10:55,220 Mike Scharf: So all our neurotoxic insecticides that we have, you know, they're targeting the nervous system throughout the body like we see here. 111 00:10:57,019 --> 00:11:04,320 Mike Scharf: The insect cuticle is made up of - it's actually very complex and it's made up of a lot of 112 00:11:04,440 --> 00:11:09,959 Mike Scharf: different layers and so if we think about insect growth regulators and so they're disrupting 113 00:11:09,970 --> 00:11:13,480 Mike Scharf: the formation of the cuticle and that can have really 114 00:11:14,699 --> 00:11:19,759 Mike Scharf: pronounced consequences on the insect, but we just disrupt the subtle nature of the cuticle. 115 00:11:20,199 --> 00:11:24,300 Mike Scharf: The cuticle is also important because it's a barrier to insecticides. 116 00:11:24,639 --> 00:11:29,500 Mike Scharf: So, you know, any contact insecticides that an insect picks up in the environment, 117 00:11:29,980 --> 00:11:36,480 Mike Scharf: they have to make it through all these layers of the cuticle in order to get to the inside where the nervous system is. 118 00:11:38,340 --> 00:11:39,600 Mike Scharf: Over here is the gut. 119 00:11:39,730 --> 00:11:45,620 Mike Scharf: So this is a really nice picture from my lab of a termite gut and you can see it's a pretty 120 00:11:46,120 --> 00:11:47,180 Mike Scharf: complex kind of thing. 121 00:11:48,190 --> 00:11:53,000 Mike Scharf: And again, here's this tube that goes down the middle of the gut which is actually the 122 00:11:53,260 --> 00:11:55,360 Mike Scharf: outside of the organism. 123 00:11:55,839 --> 00:12:01,240 Mike Scharf: exterior. So for example insecticides that would be ingested, you know, they're 124 00:12:01,600 --> 00:12:05,640 Mike Scharf: they have to penetrate through these barriers of the gut to make it into the 125 00:12:05,800 --> 00:12:11,459 Mike Scharf: body to affect their target sites. So you know the gut is really complex. 126 00:12:12,880 --> 00:12:33,380 Mike Scharf: I'm jumping over here to the tracheal system. So, you know, within insects, they're a bit different than humans and other animals in that, you know, the tracheal system is this series of tubes, physical tubes that run through the whole body that bring air from the outside and deliver it to the inside of the 127 00:12:33,020 --> 00:12:39,800 Mike Scharf: of all the cells within an insect. That's different than animals and mammals like us, for example. 128 00:12:40,020 --> 00:12:45,780 Mike Scharf: We have lungs, we breathe in the oxygen, we have gas exchange happening in our lungs, 129 00:12:45,880 --> 00:12:49,800 Mike Scharf: we have hemoglobin that carries all the oxygen around in our bodies. 130 00:12:50,500 --> 00:12:53,720 Mike Scharf: That's very different than what's actually happening in insects. 131 00:12:54,160 --> 00:12:57,860 Mike Scharf: Insects have this physical plumbing kind of system with all their trachea. 132 00:12:59,300 --> 00:13:05,160 Mike Scharf: And then finally down here we have muscles and so muscles are you know what control movement and 133 00:13:05,380 --> 00:13:12,300 Mike Scharf: responses to stimuli and all these kinds of things and so within the insect they have really complex 134 00:13:13,480 --> 00:13:16,200 Mike Scharf: really complex muscular system much like our own 135 00:13:17,700 --> 00:13:23,600 Mike Scharf: and it's controlled by the nervous system of course and we have some new insecticides that 136 00:13:24,540 --> 00:13:26,700 Mike Scharf: affect the insect 137 00:13:27,080 --> 00:13:31,660 Mike Scharf: calcium channels in their muscles and this is a really important new mode of 138 00:13:31,800 --> 00:13:35,340 Mike Scharf: action that we have available that's actually very safe, it's very insect 139 00:13:35,560 --> 00:13:38,280 Mike Scharf: specific and this would be insecticides like 140 00:13:39,700 --> 00:13:41,620 Mike Scharf: like chlorantraniliprole or cyan 141 00:13:41,840 --> 00:13:45,720 Mike Scharf: traniliprole, right, really those words just roll off your tongue don't they? 142 00:13:46,140 --> 00:13:50,300 Mike Scharf: But those are the, those are insecticides that affect the insect 143 00:13:50,560 --> 00:13:52,500 Mike Scharf: muscles and they're very insect specific. 144 00:13:53,519 --> 00:13:56,639 Mike Scharf: It's good to know a little bit about musculature as well. 145 00:13:57,029 --> 00:13:58,120 Mike Scharf: We talk about this topic. 146 00:14:02,000 --> 00:14:11,480 Mike Scharf: So, moving on from insect physiology, I next want to move over to insecticides and just some very basic 147 00:14:12,040 --> 00:14:19,620 Mike Scharf: concepts and then kind of moving towards modes of action which it gets a little more complex as we go on. 148 00:14:19,630 --> 00:14:25,200 Mike Scharf: But I promise not to get too technical, at least I'll try not to with this. 149 00:14:25,920 --> 00:14:31,700 Mike Scharf: It's a very technical topic so it's hard not to get too caught up in the technical details. 150 00:14:34,280 --> 00:14:37,780 Mike Scharf: So just thinking about insecticide classification first. 151 00:14:39,480 --> 00:14:46,880 Mike Scharf: So insecticides, they have chemical structures that allow them to be classified. 152 00:14:47,440 --> 00:14:50,860 Mike Scharf: So we can think about, you know, like if we think about all the different insect groups, 153 00:14:51,320 --> 00:14:59,960 Mike Scharf: they have different kinds of morphology, different forms that allow them to be classified. 154 00:15:00,160 --> 00:15:07,699 Mike Scharf: classified in the different groups of the different taxonomic groups of the insects like termites and roaches and flies and 155 00:15:08,139 --> 00:15:11,440 Mike Scharf: you know all the different groups. So here we just have some insecticides listed. 156 00:15:12,160 --> 00:15:17,300 Mike Scharf: There won't be a quiz over this but you can see if you just look at their structures, they look very different. 157 00:15:17,699 --> 00:15:22,019 Mike Scharf: They're made up of different elements, you know, different atoms make them up. 158 00:15:22,680 --> 00:15:31,380 Mike Scharf: And these different structures are what give them different functions and allow them to target different target sites, which I'll talk about next. 159 00:15:32,000 --> 00:15:38,560 Mike Scharf: But this idea of insecticide class, target site in the insect, and then the mode of action 160 00:15:39,680 --> 00:15:43,120 Mike Scharf: at that target site. Those are all highly interconnected concepts. 161 00:15:43,930 --> 00:15:46,960 Mike Scharf: So, and it all comes back to the chemistry, unfortunately. 162 00:15:47,740 --> 00:15:50,540 Mike Scharf: Chemistry can be a really intimidating topic, but 163 00:15:51,940 --> 00:15:58,200 Mike Scharf: it all comes back to that. So, I'm not going to get into that too much though, as much as I love structures. 164 00:16:00,940 --> 00:16:07,640 Mike Scharf: So talking more about target site and mode of action, so we can think about mode of action 165 00:16:08,020 --> 00:16:10,660 Mike Scharf: as almost like it's like a target site and mode of action. 166 00:16:10,800 --> 00:16:13,520 Mike Scharf: It's like a key in a lock kind of scenario. 167 00:16:14,560 --> 00:16:20,560 Mike Scharf: So the insecticide has a very specific structure that allows it to interact with a very specific 168 00:16:20,840 --> 00:16:22,460 Mike Scharf: target site in the insect. 169 00:16:22,470 --> 00:16:23,920 Mike Scharf: So it's like a key and a lock. 170 00:16:24,300 --> 00:16:30,460 Mike Scharf: Only that chemical is going to fit in that target site and then you imagine the lock would 171 00:16:30,580 --> 00:16:35,820 Mike Scharf: open and that's like the toxicity happening in the insect. 172 00:16:35,880 --> 00:16:39,500 Mike Scharf: You're disrupting the function of that physiological target site. 173 00:16:40,459 --> 00:16:46,899 Mike Scharf: And target sites are their actual locations or physiological locations within the insects. 174 00:16:47,839 --> 00:16:54,300 Mike Scharf: And so, and this is what I'll kind of run through the different insecticide classes here coming up in the next part of this talk 175 00:16:55,140 --> 00:17:00,120 Mike Scharf: and point out the different physiological locations associated with each. 176 00:17:01,060 --> 00:17:10,780 Mike Scharf: Of course, I talked about this lock and the key analogy, but in reality, what people who study insecticide mode of action and design new insecticides, 177 00:17:10,839 --> 00:17:13,660 Mike Scharf: they're thinking in terms of what you see down here at the bottom. 178 00:17:14,280 --> 00:17:22,780 Mike Scharf: You know, the target side, it's a protein, usually within the insect. It's got three-dimensional structure like the lock. 179 00:17:23,419 --> 00:17:31,140 Mike Scharf: And the insecticides actually, chemical structures can dock up with that target and, you know, disrupt it. 180 00:17:31,640 --> 00:17:35,200 Mike Scharf: So it's actually not as, it's way more complex than the key in the lock. 181 00:17:35,539 --> 00:17:39,520 Mike Scharf: But thanks to modern science we can predict these things very well. 182 00:17:39,660 --> 00:17:44,559 Mike Scharf: And it's actually very similar to drug discovery and drug design as well. 183 00:17:44,900 --> 00:17:50,840 Mike Scharf: So really the drug field and the insecticide field have a lot of overlap, believe it or not. 184 00:17:51,820 --> 00:17:58,500 Mike Scharf: But bringing it back to just these four very basic modes of action of the insecticides. 185 00:17:59,200 --> 00:18:01,960 Mike Scharf: So target sites are physiological location. 186 00:18:02,700 --> 00:18:07,440 Mike Scharf: Modes of action are the actions of insecticides at those target sites. 187 00:18:08,240 --> 00:18:11,000 Mike Scharf: And we can really break it down into four modes of action. 188 00:18:11,139 --> 00:18:13,380 Mike Scharf: There are only four kinds that occur. 189 00:18:14,280 --> 00:18:20,200 Mike Scharf: So that would be stimulation or blockage, especially with nerves. 190 00:18:20,500 --> 00:18:23,740 Mike Scharf: So if you stimulate a nerve, you cause it to fire more rapidly. 191 00:18:24,460 --> 00:18:26,960 Mike Scharf: And if you block it, you basically shut it off. 192 00:18:27,120 --> 00:18:28,260 Mike Scharf: You keep it from firing. 193 00:18:29,300 --> 00:18:31,340 Mike Scharf: So we have pesticides that do both those things. 194 00:18:32,100 --> 00:18:36,100 Mike Scharf: We have other things that are called modulators, like pyrethroids. 195 00:18:36,430 --> 00:18:40,100 Mike Scharf: If you know anything about pyrethroids, they're modulators. 196 00:18:40,590 --> 00:18:46,940 Mike Scharf: So they're binding their target site and just kind of modulating its shape, changing the 197 00:18:47,020 --> 00:18:49,200 Mike Scharf: subtle ways that it functions by... 198 00:18:49,639 --> 00:18:55,240 Mike Scharf: by modulating its shape. And then the last one here is inhibition. So we have a lot of 199 00:18:55,960 --> 00:19:02,360 Mike Scharf: insecticides that actually inhibit certain enzymes in the nervous system like acetylcholinesterase enzymes, 200 00:19:03,029 --> 00:19:07,220 Mike Scharf: which we may all know about are the target sites of organophosphates. 201 00:19:07,860 --> 00:19:13,160 Mike Scharf: and carbamates, which I'll talk about too. But we have these just these very four basic 202 00:19:13,419 --> 00:19:19,340 Mike Scharf: kinds of modes of action and it's very simple actually. So when I'm teaching my toxicology 203 00:19:19,490 --> 00:19:26,100 Mike Scharf: class at Purdue University, this is just how I kind of lay it out and it's very easy to 204 00:19:26,299 --> 00:19:31,799 Mike Scharf: understand these concepts when you just recognize there are only four ways that target sites can 205 00:19:31,799 --> 00:19:32,340 Mike Scharf: be disrupted. 206 00:19:33,560 --> 00:19:35,640 Mike Scharf: But, that's all I will say about that. 207 00:19:36,580 --> 00:19:38,300 Mike Scharf: Try not to get too technical here. 208 00:19:41,820 --> 00:19:48,680 Mike Scharf: So there's another concept which is the concept of the LD50. 209 00:19:49,500 --> 00:19:57,320 Mike Scharf: And so LD50 is the lethal dose that would kill 50% of your test insect that you're looking at. 210 00:19:57,429 --> 00:20:03,419 Mike Scharf: So every insecticide has a different LD50 that's unique to that insecticide. 211 00:20:03,450 --> 00:20:09,740 Mike Scharf: So, you know, not all different insecticides have different dose ranges at which they're effective. 212 00:20:10,320 --> 00:20:15,480 Mike Scharf: That's just the very nature of the chemistry and the physiology that's going on. 213 00:20:16,360 --> 00:20:23,280 Mike Scharf: So in general we can say that the relationship between product toxicity and LD50 is inverse. 214 00:20:24,000 --> 00:20:29,480 Mike Scharf: So the smaller the LD50, the higher the toxicity of a product. 215 00:20:29,840 --> 00:20:36,380 Mike Scharf: That means, so if an LD50 is small, that means that you only need a small dose to kill half 216 00:20:36,400 --> 00:20:37,540 Mike Scharf: of your test population. 217 00:20:38,420 --> 00:20:47,260 Mike Scharf: And over all of it, it's just these insecticides are active at the smaller dose equals greater toxicity. 218 00:20:49,520 --> 00:20:53,360 Mike Scharf: Insecticides that are more toxic or hazardous have lower LD50s. 219 00:20:53,450 --> 00:20:55,700 Mike Scharf: Again, that's just reinforcing what I just said. 220 00:20:56,380 --> 00:21:05,600 Mike Scharf: And insecticides that we have today are actually much more toxic to insects and pests than they are to people and pets. 221 00:21:06,350 --> 00:21:09,160 Mike Scharf: You know, some by over 10,000 times. 222 00:21:09,550 --> 00:21:17,860 Mike Scharf: So, that's really amazing if you think about it that, you know, thanks to modern science and advances and technology and human understanding, 223 00:21:18,480 --> 00:21:22,820 Mike Scharf: we're able to design insecticides today that are, you know, 224 00:21:24,020 --> 00:21:27,640 Mike Scharf: Some are actually completely safe for mammals. 225 00:21:28,280 --> 00:21:33,360 Mike Scharf: I'll point out some of these as the talk goes on, but we have insecticide classes like the 226 00:21:33,560 --> 00:21:37,640 Mike Scharf: diamides which don't have a signal word, if you can imagine that. 227 00:21:38,190 --> 00:21:43,100 Mike Scharf: So they have their mammalian toxicity is so low that they are not required to have a 228 00:21:43,230 --> 00:21:43,680 Mike Scharf: signal word. 229 00:21:44,380 --> 00:21:47,700 Mike Scharf: Although, that doesn't mean that we shouldn't practice safety with them. 230 00:21:49,139 --> 00:21:56,019 Mike Scharf: Another idea that's connected to this is that only very small amounts of insecticide that are placed in the environment 231 00:21:56,919 --> 00:22:00,779 Mike Scharf: of the pest actually reach their target site to cause toxicity. 232 00:22:01,360 --> 00:22:09,600 Mike Scharf: So the ratio is like billions to one, maybe even higher than that of the actual amount of insecticide that goes out in the environment 233 00:22:10,320 --> 00:22:15,960 Mike Scharf: to what is contacted by the insect and travels through its body to reach the target site and have an effect, 234 00:22:16,620 --> 00:22:19,960 Mike Scharf: you know, it's only a billion or less of what's actually placed out there. 235 00:22:20,679 --> 00:22:24,820 Mike Scharf: And a lot of that goes along with the insecticides just being so pest specific. 236 00:22:26,080 --> 00:22:33,720 Mike Scharf: So, I think we're moving in a really good direction as a whole in terms of being able to have safer products today. 237 00:22:34,780 --> 00:22:41,760 Mike Scharf: They have high mammalian LD50s and low insect LD50s. 238 00:22:46,160 --> 00:22:54,840 Mike Scharf: So moving on then to the different insecticide classifications and by mode of action and 239 00:22:54,840 --> 00:22:55,980 Mike Scharf: different chemistry groups. 240 00:22:58,580 --> 00:23:05,539 Mike Scharf: We have insecticides that target the nervous system and there are five major classifications here that I'll talk about. 241 00:23:06,380 --> 00:23:09,519 Mike Scharf: And then we have insecticides that do not target the nervous system. 242 00:23:09,630 --> 00:23:14,639 Mike Scharf: So if you're just thinking about very broad classifications out there, 243 00:23:15,740 --> 00:23:21,279 Mike Scharf: you know, we can break them down into things that target the nervous system and things that do not target the nervous system. 244 00:23:21,120 --> 00:23:27,679 Mike Scharf: And I'll talk about five categories here in the first, five classifications of neurotoxins 245 00:23:28,230 --> 00:23:33,200 Mike Scharf: and then four classifications of products that are not neurotoxins. 246 00:23:36,600 --> 00:23:44,380 Mike Scharf: So moving on the first topic of things that are neurotoxins, talk a little bit about the insect nervous system. 247 00:23:45,500 --> 00:23:49,520 Mike Scharf: So the insect nervous system is made up of millions of nerve cells. 248 00:23:49,920 --> 00:23:52,300 Mike Scharf: So it's pretty amazing when you think about it. 249 00:23:52,380 --> 00:23:58,180 Mike Scharf: And these are some images from one of my favorite textbooks from Chapman. 250 00:23:58,780 --> 00:24:04,919 Mike Scharf: the insect structure and function. So I learned a lot from this book as a student a few years ago. 251 00:24:06,299 --> 00:24:10,580 Mike Scharf: When you think about nerve cells, this is kind of what they look like and I don't really need to talk about 252 00:24:11,500 --> 00:24:15,179 Mike Scharf: what's the different classifications of them, but you know, 253 00:24:15,820 --> 00:24:21,539 Mike Scharf: individual nerve cells are what make up the whole nervous system like we see over here on the right. 254 00:24:22,360 --> 00:24:27,060 Mike Scharf: And so it's pretty amazing when you think about, so like, you know, hold your arm out 255 00:24:27,640 --> 00:24:28,880 Mike Scharf: and snap your finger. 256 00:24:29,740 --> 00:24:34,760 Mike Scharf: And think about the signal traveling through your whole nervous system, how fast that happens 257 00:24:34,960 --> 00:24:38,000 Mike Scharf: from your brain to the muscles in your finger. 258 00:24:38,600 --> 00:24:41,260 Mike Scharf: And then, you know, you heard the snap of your finger. 259 00:24:41,620 --> 00:24:44,340 Mike Scharf: That information traveled back from your ears to your brain. 260 00:24:45,100 --> 00:24:49,120 Mike Scharf: You know, the nervous system moves at amazing speeds. 261 00:24:49,500 --> 00:24:50,920 Mike Scharf: Things happen incredibly fast. 262 00:24:51,520 --> 00:24:58,120 Mike Scharf: it's mind-boggling to think about. So we have all these cells, nerve cells, in the 263 00:24:58,190 --> 00:25:03,140 Mike Scharf: nervous system that are affected by insecticides. They also control the 264 00:25:03,300 --> 00:25:07,220 Mike Scharf: function of the nervous system in a really integrated kind of way. 265 00:25:09,380 --> 00:25:11,620 Mike Scharf: So how does the nervous system actually work? 266 00:25:12,780 --> 00:25:17,460 Mike Scharf: Again, try not to get too technical here because this is not a neurobiology course, 267 00:25:18,460 --> 00:25:23,260 Mike Scharf: but we can say that information travels through the nervous system in the form of electrical impulses. 268 00:25:23,700 --> 00:25:27,000 Mike Scharf: So these impulses are moving at the speed of light, basically. 269 00:25:27,440 --> 00:25:35,240 Mike Scharf: Think about that analogy of snapping your fingers and that signal moving at the speed of light down a neuron. 270 00:25:35,710 --> 00:25:39,560 Mike Scharf: So this is electrical energy moving down a nerve cell. 271 00:25:40,330 --> 00:25:47,560 Mike Scharf: And then, so remember the nervous system is composed of millions of cells and there are gaps between these cells called synapses. 272 00:25:48,059 --> 00:25:51,460 Mike Scharf: So that's what this would be here in the middle, this gap between two neurons. 273 00:25:52,580 --> 00:25:59,720 Mike Scharf: And so the electrical information, when it reaches the end of a nerve cell, then it becomes 274 00:26:00,440 --> 00:26:04,419 Mike Scharf: chemical information in the form of a neurotransmitter that will cross that gap. 275 00:26:05,940 --> 00:26:13,400 Mike Scharf: And those neurotransmitters bind a receptor on the other side and those are very specific to the different kinds of neurotransmitters. 276 00:26:13,870 --> 00:26:20,060 Mike Scharf: And then instantly, you know, at the speed of light that becomes electrical information again moving down the next neuron. 277 00:26:20,700 --> 00:26:24,960 Mike Scharf: So we have impulses that move in the form of electricity. 278 00:26:26,659 --> 00:26:31,019 Mike Scharf: through nerves and then those impulses cross gaps in the form of chemical 279 00:26:31,340 --> 00:26:35,360 Mike Scharf: messengers called neurotransmitters and those neurotransmitters bind receptors 280 00:26:35,720 --> 00:26:39,519 Mike Scharf: that carry the information to the next neuron. And again this is all happening 281 00:26:40,010 --> 00:26:44,019 Mike Scharf: at the speed of light. So pretty fascinating. 282 00:26:45,940 --> 00:26:53,279 Mike Scharf: So, you know, in my lab, we study insecticide effects on the insect nervous system. 283 00:26:53,700 --> 00:26:55,279 Mike Scharf: So, how do we do that? 284 00:26:55,519 --> 00:27:02,639 Mike Scharf: We use a neurophysiology system, which is pretty fun and informative. 285 00:27:02,980 --> 00:27:05,639 Mike Scharf: You can do really good science with this kind of approach. 286 00:27:06,860 --> 00:27:11,800 Mike Scharf: And so here's an example of this is an American cockroach that's been dissected 287 00:27:11,880 --> 00:27:17,680 Mike Scharf: open by one of my students who has really good hands, hands of a surgeon as we joke 288 00:27:17,800 --> 00:27:23,600 Mike Scharf: and say. And you can see right here this is the ventral nerve cord of the American 289 00:27:23,800 --> 00:27:27,780 Mike Scharf: cockroach. And all these little squiggly lines here, those are the trachea I mentioned. 290 00:27:27,520 --> 00:27:32,980 Mike Scharf: That's the those are the breathing tubes. You can't really see the nerve, but it's right down here in the middle. 291 00:27:33,520 --> 00:27:39,080 Mike Scharf: And we can stick an electrode onto that neuron and then a nerve cord and 292 00:27:39,820 --> 00:27:46,400 Mike Scharf: measure the electrical activity doing that. So this is an example of kind of like baseline activity. 293 00:27:46,640 --> 00:27:55,040 Mike Scharf: This is five minutes of recording. This is just the nerve kind of, you know, the insect obviously is dissected open and the nerves firing away. 294 00:27:56,080 --> 00:27:59,880 Mike Scharf: for five minutes and then if you apply an insecticide like Fipronil, 295 00:28:00,950 --> 00:28:03,080 Mike Scharf: so Fipronil causes neuroexcitation. 296 00:28:04,000 --> 00:28:07,659 Mike Scharf: You can see here's an example then of what happens to the nerve 297 00:28:08,149 --> 00:28:12,279 Mike Scharf: after that. It's firing at a much more rapid rate 298 00:28:12,659 --> 00:28:15,760 Mike Scharf: and with a higher magnitude of intensity. 299 00:28:17,580 --> 00:28:27,940 Mike Scharf: And so we can, you can look at the nerves and you can see these effects very clearly with neurotoxins, which is, you can see what is happening. 300 00:28:28,860 --> 00:28:38,400 Mike Scharf: So it's really informative and I think this kind of graphic really helps to bring it home and show some of the physiology that's going on. 301 00:28:40,520 --> 00:28:55,120 Mike Scharf: So moving along to insecticides that target sites in the nervous system, so I'm going to talk about these and the insecticides that affect them. So sodium channels, chloride channels, 302 00:28:56,039 --> 00:29:01,399 Mike Scharf: Acetylcholine receptors, need this acetylcholinesterase enzyme and then we'll talk about combination 303 00:29:01,980 --> 00:29:05,480 Mike Scharf: products that target multiple locations at once. 304 00:29:05,860 --> 00:29:10,600 Mike Scharf: We have a lot more combination products available to us now and so it's good to understand how 305 00:29:10,600 --> 00:29:12,120 Mike Scharf: they work in collaboration. 306 00:29:15,559 --> 00:29:20,760 Mike Scharf: So here are some of the target sites in the nervous system and I don't want to get into 307 00:29:20,820 --> 00:29:21,419 Mike Scharf: this too much. 308 00:29:21,580 --> 00:29:26,620 Mike Scharf: This is a little bit technical but the next couple of slides I throw up here, those are 309 00:29:26,620 --> 00:29:32,539 Mike Scharf: going to be available in some of the supplementary material that I showed you at the beginning 310 00:29:32,580 --> 00:29:34,039 Mike Scharf: of the talk and I'll mention. 311 00:29:34,399 --> 00:29:39,500 Mike Scharf: get at the end. But these are just, this is just a, I'm trying to show here where 312 00:29:39,760 --> 00:29:46,340 Mike Scharf: the different target sites are on neurons. And so we have chloride channels 313 00:29:46,899 --> 00:29:53,000 Mike Scharf: here which are at the, they occur after the synapse right here. So the GABA receptor 314 00:29:53,399 --> 00:29:55,820 Mike Scharf: and the glutamate receptor are actually chloride channels. 315 00:29:56,580 --> 00:30:00,600 Mike Scharf: Here's the acetylcholine receptor. It's actually a sodium channel. 316 00:30:01,620 --> 00:30:06,000 Mike Scharf: Let's sodium into neurons. Not to be confused with these other things called 317 00:30:06,380 --> 00:30:08,900 Mike Scharf: sodium channels. You realize that can be really confusing. 318 00:30:09,500 --> 00:30:12,300 Mike Scharf: But it's so these sodium channels that are on the axon 319 00:30:12,700 --> 00:30:17,920 Mike Scharf: of the nerve, the long skinny part of it, these are the actual on switch 320 00:30:18,500 --> 00:30:22,200 Mike Scharf: for a nerve cell. So pyrethroids target these sodium channels. 321 00:30:23,840 --> 00:30:27,480 Mike Scharf: Here's a, again, here's a synapse, the acetylcholine receptor is here. 322 00:30:28,300 --> 00:30:37,040 Mike Scharf: Here's acetylcholine, which is a neurotransmitter that will cross that synapse and bind the acetylcholine receptor. 323 00:30:38,260 --> 00:30:43,960 Mike Scharf: And over here then you can imagine this would be a muscle that would be controlled by these nerves. 324 00:30:44,470 --> 00:30:49,460 Mike Scharf: And we have calcium channels that control muscle contraction that are targeted. 325 00:30:49,790 --> 00:30:53,720 Mike Scharf: Those are the targets of diamide insecticides that I'll be talking about too. 326 00:30:54,150 --> 00:30:59,540 Mike Scharf: So all these different, I guess the main point here is that these different physiological target sites 327 00:30:59,960 --> 00:31:02,620 Mike Scharf: appear on different locations of the nerves. 328 00:31:03,220 --> 00:31:07,460 Mike Scharf: They're doing different things for the natural function of the nerves. 329 00:31:07,740 --> 00:31:11,520 Mike Scharf: So the insecticides, when they disrupt them, they'll have different effects that we can 330 00:31:11,660 --> 00:31:11,820 Mike Scharf: see. 331 00:31:14,870 --> 00:31:18,060 Mike Scharf: And again, this is just a more maybe too technical information. 332 00:31:18,720 --> 00:31:21,360 Mike Scharf: The top part is the previous slide showing the different 333 00:31:23,000 --> 00:31:27,020 Mike Scharf: different channels, chloride, sodium, etc., acetylcholine. 334 00:31:27,380 --> 00:31:33,020 Mike Scharf: And these down here in the bottom, these are the insecticides that are affecting these different locations. 335 00:31:33,420 --> 00:31:37,040 Mike Scharf: So, phenylpyrazole like fipronil affect chloride channels, 336 00:31:37,900 --> 00:31:41,140 Mike Scharf: avermectins affect glutamate chloride channels, 337 00:31:42,100 --> 00:31:45,940 Mike Scharf: Neonicotinoids and spinosyns affect the acetylcholine receptor, 338 00:31:46,980 --> 00:31:49,240 Mike Scharf: pyrethrins and pyrethroids and 339 00:31:49,820 --> 00:31:54,380 Mike Scharf: Indoxacarb affect these axon sodium channels, 340 00:31:56,059 --> 00:31:59,320 Mike Scharf: diamides affect muscular calcium channels, etc. 341 00:32:00,100 --> 00:32:04,700 Mike Scharf: I'll get into these in more detail, but this is just kind of a roadmap 342 00:32:05,500 --> 00:32:11,720 Mike Scharf: showing you the different physiological locations of the target sites and then the insecticide 343 00:32:11,920 --> 00:32:13,460 Mike Scharf: classes that affect them. 344 00:32:13,700 --> 00:32:21,460 Mike Scharf: And again, you can reference this information in some of the handouts that I'll show at the 345 00:32:21,560 --> 00:32:21,740 Mike Scharf: end. 346 00:32:23,980 --> 00:32:29,460 Mike Scharf: So first off is the actual sodium channel insecticides that I want to talk about here. 347 00:32:29,870 --> 00:32:33,200 Mike Scharf: So these sodium channels again, they're on the axon of the nerve. 348 00:32:33,590 --> 00:32:38,680 Mike Scharf: So they're on this long skinny part of the nerve and they're really the on switch for the neuron. 349 00:32:39,440 --> 00:32:48,039 Mike Scharf: You know when they open, nerve impulses move in the form of electricity are moving down the nerve. 350 00:32:48,710 --> 00:32:55,580 Mike Scharf: So we have pyrethroids and also DDT and pyrethrins are in this category too. 351 00:32:56,150 --> 00:33:01,700 Mike Scharf: They stimulate sodium channels and cause excitation, so they'll cause that nerve 352 00:33:02,340 --> 00:33:09,860 Mike Scharf: to fire which causes the insect to, I'm sure everybody has seen insects, for example, treated with pyrethrins. 353 00:33:10,480 --> 00:33:21,940 Mike Scharf: They get knocked down right away. So that's that incoordination of their nervous system caused by that hyper excitation from their sodium channels being stimulated. 354 00:33:22,960 --> 00:33:29,880 Mike Scharf: We have oxodiazines, so this is indoxacarb, you know, really big urban insecticides that we have. 355 00:33:30,190 --> 00:33:34,340 Mike Scharf: They affect, indoxacarb affects the sodium channel but it blocks it. 356 00:33:34,630 --> 00:33:40,560 Mike Scharf: So it works in a completely different way, causes inhibition and then the insect is actually paralyzed 357 00:33:41,130 --> 00:33:46,560 Mike Scharf: because its sodium channels don't work, you know, the on switch is stuck in the off position basically. 358 00:33:47,620 --> 00:33:52,320 Mike Scharf: We also have a new newer insecticide called metaflumizone, which is a 359 00:33:52,430 --> 00:33:56,700 Mike Scharf: semicarbazone. This could be, I know there are ectoparasite uses for this 360 00:33:57,170 --> 00:34:03,080 Mike Scharf: product and possibly some other urban product uses as well. It also blocks 361 00:34:03,670 --> 00:34:07,760 Mike Scharf: sodium channels. So we can, at sodium channels we can stimulate them or block 362 00:34:07,810 --> 00:34:10,380 Mike Scharf: them depending on the different insecticide chemistries. 363 00:34:12,399 --> 00:34:21,159 Mike Scharf: Moving along to chloride channels, so chloride channels are located along the neuron and they 364 00:34:21,399 --> 00:34:25,020 Mike Scharf: cause chloride to flow into neurons which actually mellows them out. 365 00:34:25,200 --> 00:34:31,340 Mike Scharf: So chloride has a negative charge that kind of brings down the activity of the neuron under 366 00:34:31,480 --> 00:34:32,260 Mike Scharf: natural conditions. 367 00:34:33,419 --> 00:34:38,440 Mike Scharf: But we have one of our biggest insecticides in the urban market is 368 00:34:38,579 --> 00:34:43,599 Mike Scharf: Fipronil. Everybody knows that I'm sure. It's not actually off patent now. There's 369 00:34:43,669 --> 00:34:47,980 Mike Scharf: a lot of consumer products that have Fipronil in them as well now. 370 00:34:48,760 --> 00:34:53,200 Mike Scharf: Fipronil blocks the chloride channel so you're blocking this mellowing effect 371 00:34:53,690 --> 00:34:58,200 Mike Scharf: which leads to excitation. And remember that nerve recording picture I showed you 372 00:34:58,359 --> 00:35:05,900 Mike Scharf: You can see like we can apply fipronil and very quickly we can see the excitation happening in the nervous system. 373 00:35:06,690 --> 00:35:17,480 Mike Scharf: So we also have the Isoxazolines, this is a new word for me, this new class of insecticides has a lot of 374 00:35:18,589 --> 00:35:22,020 Mike Scharf: anti-parasitic uses especially on pet products. 375 00:35:22,860 --> 00:35:25,180 Mike Scharf: Names here are fluralaner and sarolaner. 376 00:35:25,300 --> 00:35:27,940 Mike Scharf: So this could be really big in the flea market, these products. 377 00:35:28,960 --> 00:35:32,960 Mike Scharf: It's good to know because vets are prescribing these things. 378 00:35:33,500 --> 00:35:38,620 Mike Scharf: They're out there in probably really good quantities and they compete with Fipronil so 379 00:35:38,740 --> 00:35:41,320 Mike Scharf: that we can see some cross-resistance issues between them. 380 00:35:41,120 --> 00:35:46,420 Mike Scharf: these two. So something to keep an eye on. These are still really new products but 381 00:35:48,120 --> 00:35:52,760 Mike Scharf: something to think about. Again those cause excitation. We also have the 382 00:35:53,660 --> 00:35:59,920 Mike Scharf: avermectins like abamectin, like a really good gel bait active ingredient that we have currently. 383 00:36:02,859 --> 00:36:07,500 Mike Scharf: Abamectin stimulates the chloride channels which leads to inhibition so that actually 384 00:36:08,460 --> 00:36:09,540 Mike Scharf: paralyzes the insect. 385 00:36:09,550 --> 00:36:13,960 Mike Scharf: It has the opposite effect of what fipronil would have even though they're both affecting 386 00:36:14,880 --> 00:36:16,079 Mike Scharf: the same target site basically. 387 00:36:16,290 --> 00:36:17,800 Mike Scharf: They just do it in opposite ways. 388 00:36:20,900 --> 00:36:24,600 Mike Scharf: Moving along to acetylcholine receptor insecticides. 389 00:36:25,160 --> 00:36:30,560 Mike Scharf: So remember here we have one neuron with the electrical impulse traveling along it. 390 00:36:30,560 --> 00:36:36,500 Mike Scharf: We have a synapse here and then we have another downstream neuron as we would say in the business. 391 00:36:37,480 --> 00:36:39,740 Mike Scharf: And so here's the synapse. 392 00:36:39,880 --> 00:36:46,120 Mike Scharf: So acetylcholine is a neurotransmitter that crosses that synapse to bind its receptor on 393 00:36:46,180 --> 00:36:46,780 Mike Scharf: the next neuron. 394 00:36:47,700 --> 00:36:54,360 Mike Scharf: And so we have our mainly the nicotinoids, you know the huge market share right now with these products. 395 00:36:54,770 --> 00:37:02,260 Mike Scharf: They're affecting the acetylcholine receptor by stimulating it and causing kind of excitation in the insect. 396 00:37:03,880 --> 00:37:10,460 Mike Scharf: And so we also have a new class called the sulfoximines or sulfoxaflor. 397 00:37:10,680 --> 00:37:12,000 Mike Scharf: It's a new product you may be seeing. 398 00:37:12,580 --> 00:37:17,560 Mike Scharf: It acts at the same target site and probably spinosyns maybe for those working in the landscape 399 00:37:17,850 --> 00:37:26,080 Mike Scharf: market have heard of spinosad and it basically affects the acetylcholine receptor in the same 400 00:37:26,260 --> 00:37:26,380 Mike Scharf: way. 401 00:37:28,420 --> 00:37:34,600 Mike Scharf: We also have the acetylcholinesterase inhibitors so they're acting to inhibit acetylcholine 402 00:37:35,460 --> 00:37:40,140 Mike Scharf: and that's the organophosphates and the carbamates which we probably, anybody who's been in the 403 00:37:40,320 --> 00:37:42,520 Mike Scharf: industry a long time knows these products really well. 404 00:37:43,860 --> 00:37:48,900 Mike Scharf: They inhibit acetylcholinesterase and that causes excitation. This is not a 405 00:37:49,060 --> 00:37:53,940 Mike Scharf: really insect specific target site. You know these things work equally well 406 00:37:54,290 --> 00:37:58,660 Mike Scharf: against humans and mammals and so we have a lot of restrictions on these kinds 407 00:37:58,660 --> 00:38:01,280 Mike Scharf: of products for a good reason. 408 00:38:03,960 --> 00:38:09,640 Mike Scharf: So, next moving along to the combination products, so I think it's really important to talk about 409 00:38:09,860 --> 00:38:11,620 Mike Scharf: these so I've thrown them in here. 410 00:38:12,380 --> 00:38:15,680 Mike Scharf: All of our combination products that we have, they all start with tea. 411 00:38:16,440 --> 00:38:19,960 Mike Scharf: I'm not going to name them here because I get confused really quickly because I'm sure 412 00:38:20,200 --> 00:38:23,240 Mike Scharf: that's part of the logic in naming them all with tea. 413 00:38:24,680 --> 00:38:27,320 Mike Scharf: But they combine nicotinoids and pyrethroids. 414 00:38:27,839 --> 00:38:34,720 Mike Scharf: And so, and they cause this effect called potentiation, which is actually hitting two target sites at once. 415 00:38:35,300 --> 00:38:38,940 Mike Scharf: So you get this synergy, this one plus one equals three kind of effect. 416 00:38:39,480 --> 00:38:42,480 Mike Scharf: So again, the nicotinoids target the acetylcholine receptor. 417 00:38:43,380 --> 00:38:47,900 Mike Scharf: then the pyrethroids that are in these combo products affect the sodium channels. 418 00:38:48,220 --> 00:38:55,100 Mike Scharf: So affecting two target sites at once gives this added kind of effect. So these 419 00:38:55,180 --> 00:39:00,500 Mike Scharf: products generally work I think but you know just like anything they're not 420 00:39:00,920 --> 00:39:05,040 Mike Scharf: immune to having resistance in the pest to them. Important to keep in mind. 421 00:39:07,060 --> 00:39:11,360 Mike Scharf: So, that was the, I talked about things that targeted the nervous system there. 422 00:39:11,680 --> 00:39:16,980 Mike Scharf: Now I want to quickly go through things that affect target sites outside the nervous system. 423 00:39:17,940 --> 00:39:26,160 Mike Scharf: And so, these are the muscular calcium channels, talk about insect growth regulators here, inhibitors 424 00:39:26,160 --> 00:39:31,100 Mike Scharf: of energy production, and then the cuticle dehydrating dust last. 425 00:39:33,320 --> 00:39:35,780 Mike Scharf: So hopefully everybody is following along with that. 426 00:39:36,720 --> 00:39:49,720 Mike Scharf: If I'm going too quickly, I'll take a little pause here and maybe we can just take a little breather and maybe if anybody has any questions, you can let Dan know those through the chat box. 427 00:39:50,540 --> 00:39:55,240 Mike Scharf: But otherwise, I'll just try to keep forging ahead here and keep us on track. 428 00:39:55,520 --> 00:40:00,720 Mike Scharf: So again, moving on to insecticides that act outside the nervous system. 429 00:40:02,680 --> 00:40:07,460 Mike Scharf: So the first one here is the muscular calcium channels. 430 00:40:08,560 --> 00:40:13,300 Mike Scharf: And so again this is where, so we have a nerve that's meeting up with a muscle. 431 00:40:13,579 --> 00:40:17,660 Mike Scharf: So it's a muscle that's controlled by a nerve, they're all controlled by nerves. 432 00:40:18,300 --> 00:40:22,760 Mike Scharf: And we have these neuromuscular calcium channels that occur right at these locations. 433 00:40:23,020 --> 00:40:26,860 Mike Scharf: And when calcium comes out of them, that causes muscles to contract. 434 00:40:27,060 --> 00:40:27,820 Mike Scharf: So it's that simple. 435 00:40:28,100 --> 00:40:30,600 Mike Scharf: Calcium equals muscle contraction. 436 00:40:31,740 --> 00:40:35,000 Mike Scharf: And so these products we have here are the diamides. 437 00:40:35,280 --> 00:40:41,680 Mike Scharf: So we have chlorantraniliprole and now cyantraniliprole and probably there are others on the way too. 438 00:40:42,120 --> 00:40:48,960 Mike Scharf: What these things do is they stimulate the neuromuscular calcium channel and that causes that muscle to contract 439 00:40:49,640 --> 00:40:55,580 Mike Scharf: for a few hours and then it burns up all its energy and then it's inhibited and the insect just kind of is 440 00:40:56,440 --> 00:40:59,220 Mike Scharf: kind of laying there in a paralyzed state for a few days until 441 00:40:59,880 --> 00:41:03,280 Mike Scharf: all its energy is burned up and it eventually dies, sadly. 442 00:41:04,020 --> 00:41:13,600 Mike Scharf: And so these products are actually so safe for mammals that no signal words were required by the EPA initially. 443 00:41:14,280 --> 00:41:22,140 Mike Scharf: Now the manufacturers did a really smart thing in this case and said no, we're going to give them a caution signal word still, which I think is very wise. 444 00:41:23,260 --> 00:41:30,320 Mike Scharf: But these products are pretty safe. But that doesn't mean you should not follow safety guidelines when using them as well. 445 00:41:31,180 --> 00:41:41,880 Mike Scharf: So that's the muscular calcium channel toxins. And talking next about insect growth regulators, so, you know, insects as we all know, 446 00:41:42,000 --> 00:41:48,300 Mike Scharf: they have outer exoskeletons and they undergo metamorphosis. And we have different kinds of 447 00:41:49,500 --> 00:41:53,040 Mike Scharf: development that insects go through. You know they have the ametabolous 448 00:41:53,160 --> 00:41:58,000 Mike Scharf: development where the older insects look just like the younger ones except 449 00:41:58,000 --> 00:42:01,720 Mike Scharf: they're just bigger. We have incomplete metamorphosis, 450 00:42:02,540 --> 00:42:06,240 Mike Scharf: hemimetabolous insects like grasshoppers and roaches and termites. 451 00:42:07,000 --> 00:42:16,540 Mike Scharf: where the really the only difference between adults and juveniles is that adults have wings and they're reproductively competent and the juveniles are not. 452 00:42:17,200 --> 00:42:27,480 Mike Scharf: And then we have complete metamorphosis like in mosquitoes and flies and caterpillars and those kinds of things where, you know, the immatures are larvae that don't really look anything like the adult. 453 00:42:28,540 --> 00:42:45,740 Mike Scharf: And so my point in showing these is there's a lot of intricate changes that are going on in the insect cuticle as they move through development and that's all controlled by hormones and chitin synthesis enzymes that synthesize the chitin in the exoskeleton. 454 00:42:47,720 --> 00:42:52,720 Mike Scharf: So, you know, insect development is really intricate and so as an insect is going from 455 00:42:52,940 --> 00:42:58,660 Mike Scharf: egg to adult, there are all these different hormones that are changing their concentrations 456 00:42:59,320 --> 00:42:59,859 Mike Scharf: in the insect. 457 00:43:03,059 --> 00:43:07,400 Mike Scharf: You know, and that's what's controlling and some are occurring together and some are occurring alone. 458 00:43:08,579 --> 00:43:10,940 Mike Scharf: And that's what controls these really subtle changes. 459 00:43:11,520 --> 00:43:19,460 Mike Scharf: And then eventually they bolt and this is a really nice set of photos of an alate termite that has just emerged by one of my former students. 460 00:43:20,500 --> 00:43:28,119 Mike Scharf: You can see like they emerge and they have to expand their wings and their structures and they have to shed their old skin effectively. 461 00:43:29,020 --> 00:43:31,740 Mike Scharf: And then they can become a normal adult eventually. 462 00:43:32,789 --> 00:43:35,240 Mike Scharf: They darken up over time too. 463 00:43:35,710 --> 00:43:37,059 Mike Scharf: Their cuticle gets tanned. 464 00:43:37,109 --> 00:43:43,579 Mike Scharf: So lots of hormones here acting in concert that can be disrupted for insect control purposes. 465 00:43:44,880 --> 00:43:47,260 Mike Scharf: And that's where the insect growth regulators come into play. 466 00:43:48,050 --> 00:43:53,100 Mike Scharf: We have the juvenile hormone analogs and the chitin synthesis inhibitors. 467 00:43:53,260 --> 00:43:56,040 Mike Scharf: Those are the two big ones that we have in the urban market. 468 00:43:57,100 --> 00:44:02,360 Mike Scharf: Juvenile hormone analogs, they mimic juvenile hormone and this leads to cuticle deformation 469 00:44:03,180 --> 00:44:05,580 Mike Scharf: and actually extra juvenile stages which 470 00:44:06,180 --> 00:44:12,740 Mike Scharf: You know if you have juveniles that can't mate that can cause the population to crash so that's part of the strategy there. 471 00:44:13,540 --> 00:44:17,040 Mike Scharf: With IGRs like pyriproxyfen for example, 472 00:44:17,620 --> 00:44:20,680 Mike Scharf: we see you can see this wing twist happening in 473 00:44:21,000 --> 00:44:25,080 Mike Scharf: insects as they like cockroaches especially as they move through development. 474 00:44:25,180 --> 00:44:29,300 Mike Scharf: So if you go into a new account and you see individuals with wing twist and 475 00:44:29,680 --> 00:44:36,340 Mike Scharf: you can put good money down on the fact that IGRs are in that population 476 00:44:36,840 --> 00:44:42,340 Mike Scharf: affecting it. So you may not want to use them continuously with thinking of potential resistance issues. 477 00:44:42,510 --> 00:44:46,660 Mike Scharf: It might be okay to use a different product when you see wing twist in the population. 478 00:44:48,140 --> 00:44:55,060 Mike Scharf: Chitin synthesis inhibitors, they inhibit the enzyme that causes the cuticle to form in the insect 479 00:44:55,880 --> 00:45:01,620 Mike Scharf: as it's going through the molting process and chitin synthesis inhibitors can lead to death during molting. 480 00:45:02,500 --> 00:45:08,720 Mike Scharf: Some of the effects like you can see in termites treated with chitin synthesis inhibitors is they show this jackknife effect 481 00:45:08,860 --> 00:45:13,960 Mike Scharf: even well after they're done molting and this is from their cuticle being malformed. 482 00:45:15,080 --> 00:45:16,560 Mike Scharf: So that's how those things work. 483 00:45:18,160 --> 00:45:24,140 Mike Scharf: And inhibitors of energy production, a lot of products here, I don't want to get into 484 00:45:24,150 --> 00:45:29,880 Mike Scharf: them too much, but these things all target the mitochondria, which that's like the energy 485 00:45:31,140 --> 00:45:39,880 Mike Scharf: in all cells of all organisms, plants, animals, insects, whatever, fish, bacteria, you know, everybody's got mitochondria 486 00:45:40,780 --> 00:45:49,820 Mike Scharf: and there's this thing called respiration happening here and different kinds of toxins are affecting different parts of the respiratory chain. 487 00:45:51,000 --> 00:45:56,560 Mike Scharf: as we call it and I don't want to get into that in too much detail because there's a lot of different things going on here. 488 00:45:56,720 --> 00:46:00,200 Mike Scharf: But some of the products you may be familiar with are hydramethylnon, 489 00:46:00,560 --> 00:46:02,480 Mike Scharf: you know, it's a cockroach bait, 490 00:46:03,740 --> 00:46:07,840 Mike Scharf: chlorfenapyr, that's like, you know, a good product that we have. It's got a food label. 491 00:46:08,320 --> 00:46:09,160 Mike Scharf: It's pretty safe. 492 00:46:10,400 --> 00:46:18,460 Mike Scharf: Fumigants like sulfuryl fluoride and others, methyl bromide, they inhibit mitochondria. 493 00:46:19,400 --> 00:46:25,540 Mike Scharf: And wood treatments like disodium octaborate tetrahydrate, DSOBTH, that actually 494 00:46:26,580 --> 00:46:33,120 Mike Scharf: can affect insect respiration and boric acid is very similar also affects 495 00:46:33,300 --> 00:46:37,220 Mike Scharf: insect respiration by disrupting this process. Although there's evidence also 496 00:46:37,420 --> 00:46:44,080 Mike Scharf: that boric acid can be abrasive, be like a desiccant and disrupt the actual gut 497 00:46:44,280 --> 00:46:44,420 Mike Scharf: lining. 498 00:46:47,160 --> 00:46:49,680 Mike Scharf: So those are the inhibitors of energy production. 499 00:46:50,100 --> 00:46:55,760 Mike Scharf: And lastly, so congratulations, we've made it to the last mode of action here. 500 00:46:56,340 --> 00:47:00,200 Mike Scharf: We have the cuticle dehydrating dusts and it's pretty simple what they do. 501 00:47:00,900 --> 00:47:07,300 Mike Scharf: Here we have silica gel and diatomaceous earth which are just basically finely ground glass powder. 502 00:47:07,980 --> 00:47:13,820 Mike Scharf: And those, you know, so on the outside of the insect surface there's this really fine waxy oily layer. 503 00:47:14,600 --> 00:47:17,800 Mike Scharf: that helps protect the insect from water loss basically. 504 00:47:18,480 --> 00:47:21,780 Mike Scharf: So these things, they abrade the cuticle, 505 00:47:22,400 --> 00:47:26,100 Mike Scharf: they break it down, which leads to water loss in the insect and 506 00:47:26,500 --> 00:47:30,220 Mike Scharf: lethargy, for example. So you just can look at them and see they're not 507 00:47:30,380 --> 00:47:32,180 Mike Scharf: happy after they've been exposed to these things. 508 00:47:32,980 --> 00:47:39,760 Mike Scharf: And we have diatomaceous earth which mainly contains silicon, that's the big active ingredient 509 00:47:40,040 --> 00:47:48,380 Mike Scharf: here which actually comes from the ground exoskeletons of diatoms which are organisms that have silicon 510 00:47:48,580 --> 00:47:50,740 Mike Scharf: in their outer exoskeleton. 511 00:47:51,220 --> 00:47:53,360 Mike Scharf: So it's a major source for these things. 512 00:47:54,340 --> 00:48:01,800 Mike Scharf: So that's how the dehydrating dust works. So I know that was really like a whirlwind tour of the different modes of action. 513 00:48:02,420 --> 00:48:09,300 Mike Scharf: But again, just trying to give you some basic information that you could follow up on later if you really wanted to. 514 00:48:09,380 --> 00:48:13,300 Mike Scharf: And again, I'll put up some references at the end that you can go to. 515 00:48:15,079 --> 00:48:20,579 Mike Scharf: So the last part of the talk here, so kind of coming down the home stretch, there 516 00:48:20,579 --> 00:48:26,980 Mike Scharf: are several factors that affect how well insecticides work. And so, and I just 517 00:48:27,140 --> 00:48:32,079 Mike Scharf: broke these down into stability and persistence, formulations, 518 00:48:33,060 --> 00:48:36,420 Mike Scharf: pest behavior, sanitation, and resistance. 519 00:48:36,830 --> 00:48:40,160 Mike Scharf: So this is where like you know the toxicology of the insecticides 520 00:48:40,900 --> 00:48:43,800 Mike Scharf: comes into practice in these various areas. 521 00:48:46,840 --> 00:48:49,820 Mike Scharf: So on the topic of stability and persistence 522 00:48:50,390 --> 00:48:53,220 Mike Scharf: we know that so most insecticides are oily 523 00:48:53,510 --> 00:48:56,860 Mike Scharf: in nature which helps them across the cuticle 524 00:48:57,340 --> 00:49:00,880 Mike Scharf: and membranes and reach their target sites within the insects. 525 00:49:01,440 --> 00:49:04,780 Mike Scharf: So, you know, if we think about we put oil and water, what happens? 526 00:49:06,050 --> 00:49:09,480 Mike Scharf: The two things partition in the phases. Usually the oil will float on top. 527 00:49:10,090 --> 00:49:13,280 Mike Scharf: And that's really the same thing that happens with a lot of our insecticides. 528 00:49:13,460 --> 00:49:18,760 Mike Scharf: They're very oily by their very nature. But unfortunately, in their pure raw form, 529 00:49:19,280 --> 00:49:25,940 Mike Scharf: You know, insecticides not only would they be unsafe, but also they can degrade rapidly in UV light. 530 00:49:26,170 --> 00:49:29,980 Mike Scharf: So ultraviolet light can break them down and they can be lost in the environment. 531 00:49:30,410 --> 00:49:35,920 Mike Scharf: So even though they don't dissolve in water, they can move with water and end up, you know, going, 532 00:49:36,940 --> 00:49:42,360 Mike Scharf: end up moving to places where you didn't apply them. So that's why we have formulations. 533 00:49:43,680 --> 00:49:49,220 Mike Scharf: And formulations are complex mixtures of the active ingredient, inert ingredients, and/or 534 00:49:49,480 --> 00:49:53,160 Mike Scharf: food attractants and stabilizers in the form of baits, for example. 535 00:49:53,760 --> 00:49:59,420 Mike Scharf: And these things, they enhance the stability and extend the longevity of the insecticide. 536 00:49:59,700 --> 00:50:04,700 Mike Scharf: They enhance safety, they make the product easier to handle or mix, and they keep the 537 00:50:04,800 --> 00:50:07,700 Mike Scharf: active ingredient dissolved in water effectively. 538 00:50:08,720 --> 00:50:15,260 Mike Scharf: And so some of our different formulations, which I'm sure everybody out there who is actually working in the industry on a day-to-day basis, 539 00:50:15,400 --> 00:50:19,520 Mike Scharf: you know these things really intricately well, intimately well. 540 00:50:21,020 --> 00:50:28,279 Mike Scharf: We have our bait insecticides, granulars, dusts, aerosols, fumigants, and then liquids. 541 00:50:28,960 --> 00:50:30,900 Mike Scharf: Of course, you know, we have all these different... 542 00:50:31,079 --> 00:50:34,200 Mike Scharf: forms that the insecticide will come in like the emulsifiable concentrate, 543 00:50:34,940 --> 00:50:39,020 Mike Scharf: wettable powder, microencapsulated, suspension concentrate, etc. 544 00:50:40,579 --> 00:50:46,740 Mike Scharf: So these are the formulations are physical factors, physical things that are added 545 00:50:46,809 --> 00:50:52,819 Mike Scharf: that are mixed with the insecticide active ingredient to help deliver it and make it safer 546 00:50:53,260 --> 00:50:54,559 Mike Scharf: and dissolve in water, etc. 547 00:50:55,069 --> 00:50:58,760 Mike Scharf: So we have to have formulations to make insecticides work. 548 00:51:02,580 --> 00:51:09,360 Mike Scharf: Another really interesting thing to think about is how pest behavior can impact how insecticides work. 549 00:51:10,200 --> 00:51:17,720 Mike Scharf: So, and I just have three examples here, but I'm sure people who are out there working in the field and observing things can 550 00:51:18,200 --> 00:51:23,900 Mike Scharf: can have other things to add here, but like with cockroaches we have secondary and tertiary kill. 551 00:51:24,290 --> 00:51:30,920 Mike Scharf: So, you know, if we have a cockroach that eats a bait and it either excretes, 552 00:51:31,310 --> 00:51:37,980 Mike Scharf: you know, some of the bait in its excrement or it's dead and another roach feeds on it or another roach eats its feces, 553 00:51:38,420 --> 00:51:42,480 Mike Scharf: We can have secondary kill and even tertiary kill. 554 00:51:42,720 --> 00:51:47,339 Mike Scharf: It's even been shown that insecticides can pass through the digestive tracts of two roaches 555 00:51:48,160 --> 00:51:53,619 Mike Scharf: and if a third roach eats the feces from the second roach, it can still be affected in a tertiary way. 556 00:51:54,279 --> 00:51:55,160 Mike Scharf: That's pretty fascinating. 557 00:51:56,840 --> 00:52:07,360 Mike Scharf: We have flea larvae that can be exposed to insecticides from their host, like a dog or a cat that's treated with a product that you would get from a vet, for example. 558 00:52:08,380 --> 00:52:17,840 Mike Scharf: And the adult fleas will defecate out the insecticide and the mature fleas in the vetting material will eat the feces of the adults. 559 00:52:18,100 --> 00:52:19,580 Mike Scharf: You know, it's how they get some of their nutrition. 560 00:52:20,380 --> 00:52:27,540 Mike Scharf: And so they can be secondarily affected by insecticides through their behaviors, their natural behaviors that can be exploited. 561 00:52:29,140 --> 00:52:36,120 Mike Scharf: And then another factor, I'm sure Dave Oi will talk about this a little bit in the next talk, social insects like termites and ants 562 00:52:36,560 --> 00:52:40,840 Mike Scharf: practice trophallaxis and allogrooming. So you know they're spreading food 563 00:52:41,120 --> 00:52:45,300 Mike Scharf: materials from both ends from the mouth and the anus side. They're sharing 564 00:52:45,560 --> 00:52:49,180 Mike Scharf: materials. They're also grooming each other and this can be a great way for 565 00:52:49,880 --> 00:52:54,340 Mike Scharf: insecticides to move from individual to individual. So typically we want slow 566 00:52:54,620 --> 00:52:58,640 Mike Scharf: acting insecticides in these kinds of situations in order to affect the 567 00:52:58,830 --> 00:53:01,440 Mike Scharf: maximum number of individuals in a population. 568 00:53:04,579 --> 00:53:08,220 Mike Scharf: Briefly here, sanitation, we all know it's really important. 569 00:53:10,579 --> 00:53:17,099 Mike Scharf: Despite today's insecticides being mostly pest specific and even have very selective toxicity to insects, 570 00:53:17,420 --> 00:53:19,640 Mike Scharf: poor sanitation always makes them less effective. 571 00:53:20,040 --> 00:53:26,119 Mike Scharf: So this is where the IPM mindset really comes into play to help make insecticides more effective. 572 00:53:28,000 --> 00:53:31,340 Mike Scharf: Excess food in an account will compete with bait. 573 00:53:31,740 --> 00:53:32,980 Mike Scharf: You know, that's pretty logical. 574 00:53:33,880 --> 00:53:39,020 Mike Scharf: If we can eliminate that competing food, we can get the more bait to be eaten by the pests 575 00:53:39,020 --> 00:53:39,760 Mike Scharf: we're trying to target. 576 00:53:41,120 --> 00:53:44,320 Mike Scharf: Clutter creates excess harborage that can't be treated. 577 00:53:44,960 --> 00:53:50,640 Mike Scharf: We've all been in that mega cockroach account that maybe looks like the top here where everything 578 00:53:50,660 --> 00:53:54,200 Mike Scharf: is moving and you certainly, you know, we can't treat all that surface. 579 00:53:54,580 --> 00:53:55,920 Mike Scharf: You know, legally we can't. 580 00:53:55,920 --> 00:53:58,799 Mike Scharf: treated and so that's a problem. 581 00:53:59,640 --> 00:54:02,160 Mike Scharf: And dirt and grease tie up insecticides too. 582 00:54:02,279 --> 00:54:08,980 Mike Scharf: So this is an extreme case here in the bottom but the insecticide is going to be less effective 583 00:54:09,099 --> 00:54:09,760 Mike Scharf: in that environment. 584 00:54:10,039 --> 00:54:11,140 Mike Scharf: Absolutely no question. 585 00:54:11,559 --> 00:54:16,460 Mike Scharf: So this is where the IPM mindset comes into play with making insecticides more effective. 586 00:54:19,000 --> 00:54:21,600 Mike Scharf: Another important factor here is resistance. 587 00:54:22,440 --> 00:54:25,680 Mike Scharf: So this is where kind of toxicology interfaces with practice 588 00:54:26,340 --> 00:54:30,460 Mike Scharf: in a really big way. This is something I study, maybe I'm most well known for 589 00:54:31,240 --> 00:54:34,720 Mike Scharf: working on insecticide resistance. I would argue that 590 00:54:35,140 --> 00:54:38,060 Mike Scharf: resistance is probably the number one cause of callbacks 591 00:54:38,240 --> 00:54:39,260 Mike Scharf: in cockroach accounts. 592 00:54:40,099 --> 00:54:43,800 Mike Scharf: Some of the things we've seen in recent years are just amazing, even with baits. 593 00:54:45,339 --> 00:54:50,680 Mike Scharf: We've seen cockroaches that can eat bait as their only food source for a month and survive. 594 00:54:51,369 --> 00:54:53,240 Mike Scharf: So, pretty mind-boggling. 595 00:54:54,550 --> 00:54:58,760 Mike Scharf: You know, bedbugs, pyrethroid resistance is widespread, we know that. 596 00:55:00,420 --> 00:55:05,520 Mike Scharf: But there's also newer evidence of resistance to other active ingredients. 597 00:55:05,660 --> 00:55:11,640 Mike Scharf: Not picking on chlorfenapyr here, but the potential is there for resistance to not only this active ingredient, 598 00:55:11,720 --> 00:55:13,599 Mike Scharf: but to nicotinoids as well as others. 599 00:55:14,640 --> 00:55:16,640 Mike Scharf: It's just a really big problem. 600 00:55:16,760 --> 00:55:23,480 Mike Scharf: The pests are always adapting with resistance and we have to figure out how to stay ahead of it to have our products keep working. 601 00:55:23,860 --> 00:55:29,640 Mike Scharf: One way to do that is product rotation, it seems to be key for long-term success. 602 00:55:30,280 --> 00:55:37,560 Mike Scharf: And even with mixture products, so those mixture products that start with tea that combine two active ingredients, 603 00:55:38,240 --> 00:55:43,560 Mike Scharf: we even need to use those in rotation so I've learned, so we've learned. 604 00:55:43,820 --> 00:55:48,620 Mike Scharf: This is a typical rotation scheme that we've been recommending for years for cockroaches. 605 00:55:49,760 --> 00:55:55,280 Mike Scharf: Every three months switch active ingredients, maybe even every month if you can do it. 606 00:55:55,700 --> 00:56:02,280 Mike Scharf: But we've also learned that it depends on the active ingredients you're using too. 607 00:56:02,780 --> 00:56:09,100 Mike Scharf: Not all active ingredients are going to be compatible and unfortunately the science is really lacking here. 608 00:56:09,140 --> 00:56:10,820 Mike Scharf: We hope to publish some papers soon. 609 00:56:11,320 --> 00:56:17,020 Mike Scharf: showing how which products would work the best in combination in rotations. 610 00:56:18,120 --> 00:56:26,000 Mike Scharf: But that information is still evolving and it's something definitely I would encourage the industry to be paying attention to and asking for 611 00:56:27,380 --> 00:56:28,880 Mike Scharf: in the coming months and years. 612 00:56:30,200 --> 00:56:33,440 Mike Scharf: So that kind of brings me down the home stretch. 613 00:56:34,040 --> 00:56:40,140 Mike Scharf: My summary points here are insect physiology provides unique insecticide target sites, but 614 00:56:40,160 --> 00:56:42,140 Mike Scharf: also creates penetration barriers. 615 00:56:43,710 --> 00:56:49,460 Mike Scharf: I talked about five classifications of neurotoxic insecticides, so just try to keep that in mind 616 00:56:49,540 --> 00:56:50,260 Mike Scharf: that there are five. 617 00:56:50,920 --> 00:56:53,700 Mike Scharf: and you can follow up on what they are on your own time. 618 00:56:54,420 --> 00:56:59,579 Mike Scharf: And then with non-neurotoxic insecticides, there are four classifications here that we 619 00:56:59,640 --> 00:56:59,920 Mike Scharf: have. 620 00:57:00,079 --> 00:57:06,240 Mike Scharf: So if you know what these nine classes are, as a technician or a technical manager, you 621 00:57:06,299 --> 00:57:10,660 Mike Scharf: will be able to communicate this to your customers better and maybe communicate more competence 622 00:57:11,279 --> 00:57:12,640 Mike Scharf: and also maybe be more effective. 623 00:57:13,440 --> 00:57:19,640 Mike Scharf: pest management. I'm sure he will be more effective. And lastly insecticide 624 00:57:19,760 --> 00:57:23,779 Mike Scharf: chemistry interacts with other factors like behavior and resistance and 625 00:57:23,980 --> 00:57:31,240 Mike Scharf: sanitation that impact both insecticide use and efficacy. So again big take-home 626 00:57:31,299 --> 00:57:35,740 Mike Scharf: message here, increasing your knowledge in all these areas can make you a better 627 00:57:35,760 --> 00:57:38,079 Mike Scharf: pest manager. I'm completely sure of it. 628 00:57:38,620 --> 00:57:43,840 Mike Scharf: So with that, I'll thank you for your attention and I'll put up this very last slide here. 629 00:57:44,000 --> 00:57:50,260 Mike Scharf: This is the two additional sources of information that you can go to for supporting information 630 00:57:50,370 --> 00:57:51,480 Mike Scharf: of what I presented here today. 631 00:57:51,810 --> 00:57:52,840 Mike Scharf: So thanks very much. 632 00:57:53,780 --> 00:57:55,280 Dan Suiter: All right, very good stuff, Mike. 633 00:57:56,720 --> 00:58:03,560 Dan Suiter: You commented on resistance there at the end. I think we may have to have you back for a webinar on resistance. 634 00:58:03,740 --> 00:58:08,840 Dan Suiter: Did you ever give a resistance webinar, Mike, in the past several years or was it always a mode of action? 635 00:58:09,320 --> 00:58:13,700 Mike Scharf: I did. I did give one on bedbugs and roaches. We've got more information now. 636 00:58:15,880 --> 00:58:19,940 Dan Suiter: Okay. Well, I'll see you in Denver. I might have to hit you up on that. 637 00:58:19,640 --> 00:58:24,420 Dan Suiter: on a something for next year, but we did have a there are a few really good questions that came in Mike 638 00:58:24,500 --> 00:58:29,220 Dan Suiter: I'll kind of go through those. I don't know if we'll have time to get to all of them, but I had one question here on 639 00:58:29,700 --> 00:58:35,900 Dan Suiter: combination products that since we're using combination products at lower doses, do we risk the potential of 640 00:58:36,780 --> 00:58:38,520 Dan Suiter: resistance to two chemistries at once? 641 00:58:39,280 --> 00:58:45,119 Mike Scharf: I would say even though the manufacturers don't want to hear it, I would say yes. 642 00:58:46,540 --> 00:58:52,619 Mike Scharf: We've seen evidence of resistance to both active ingredients in select roach populations. 643 00:58:53,740 --> 00:58:59,020 Mike Scharf: Roaches that are resistant to both nicotinoids and pyrethroids and that affects the product 644 00:58:59,280 --> 00:58:59,480 Mike Scharf: performance. 645 00:59:00,440 --> 00:59:00,900 Mike Scharf: So yes. 646 00:59:02,060 --> 00:59:06,300 Dan Suiter: Is it a fair statement, Mike, that just... 647 00:59:06,400 --> 00:59:10,820 Dan Suiter: The development of resistance is kind of inevitable with overuse of an active 648 00:59:11,020 --> 00:59:16,020 Dan Suiter: ingredient would you? Is that the inevitability of resistance? 649 00:59:16,560 --> 00:59:23,880 Mike Scharf: Absolutely. You know I try not to pick on products because I think that 650 00:59:24,180 --> 00:59:30,040 Mike Scharf: resistance is possible to any product and we've seen it and so it's just it's 651 00:59:30,070 --> 00:59:31,500 Mike Scharf: all a matter of 652 00:59:31,920 --> 00:59:39,020 Mike Scharf: appropriate use for lengths of time and intensities of selection. So it's 653 00:59:39,090 --> 00:59:44,840 Dan Suiter: possible always. Yeah, I guess that's what that resistance management 654 00:59:48,500 --> 00:59:50,140 Dan Suiter: ideas you were talking about are so important. 655 00:59:50,800 --> 00:59:51,560 Dan Suiter: It really is. 656 00:59:52,140 --> 00:59:52,240 Dan Suiter: Yeah. 657 00:59:53,700 --> 00:59:54,660 Dan Suiter: I had a question here. 658 00:59:54,900 --> 00:59:55,860 Dan Suiter: This is my question here. 659 00:59:56,620 --> 01:00:00,160 Dan Suiter: Talk about the flow of new active ingredients into the pest control industry. 660 01:00:00,200 --> 01:00:05,160 Dan Suiter: It seems that over the years things have kind of slowed down and the industry is kind of 661 01:00:05,860 --> 01:00:07,440 Dan Suiter: generic heavy at this point. 662 01:00:09,200 --> 01:00:13,660 Dan Suiter: What's the horizon for new active ingredients that are coming into the industry? 663 01:00:13,760 --> 01:00:18,860 Dan Suiter: Do the big manufacturers, do they all have active ingredients that they're working on? 664 01:00:19,220 --> 01:00:21,600 Dan Suiter: Will we see new actives that are coming into the market? 665 01:00:22,440 --> 01:00:28,640 Mike Scharf: Well, a lot of it depends on economics, of course, and I think all of our manufacturers 666 01:00:28,760 --> 01:00:35,200 Mike Scharf: have lots of things in the pipeline, it's just a matter of them to be able to 667 01:00:35,660 --> 01:00:40,020 Mike Scharf: you know get it into the market and have it be able to it's got to make money 668 01:00:40,470 --> 01:00:46,980 Mike Scharf: You know the markets got to be right and so they they're very careful about how they move things and get them into the market 669 01:00:47,329 --> 01:00:54,500 Mike Scharf: I think it's an expensive process. It is yes, and we have to remember the urban slice of the pie is 670 01:00:55,070 --> 01:00:58,320 Mike Scharf: you know it's not as big as agriculture and so 671 01:01:00,260 --> 01:01:07,260 Mike Scharf: This is just where we need a voice and need to keep after the manufacturers to let them know we need these things. 672 01:01:05,050 --> 01:01:05,180 Mike Scharf: I 673 01:01:08,400 --> 01:01:11,800 Dan Suiter: I had a question here about chlorantraniliprole, Mike. 674 01:01:12,390 --> 01:01:15,000 Dan Suiter: Would it have an effect on nonvertebrates like earthworms? 675 01:01:16,480 --> 01:01:27,500 Mike Scharf: That's a good question. I would suspect it probably does, but the way the labeling is, possibly not as much. 676 01:01:27,940 --> 01:01:34,119 Mike Scharf: It's a really unique molecule in terms of being super selective for even certain insect groups. 677 01:01:35,520 --> 01:01:39,859 Mike Scharf: It's possible there's some selectivity, I just haven't seen that info. 678 01:01:40,240 --> 01:01:46,240 Dan Suiter: Yeah. How about the IRAC? You didn't mention, this wasn't really a resistance talk, 679 01:01:46,300 --> 01:01:49,920 Dan Suiter: but can you mention IRAC and what that is for the audience? 680 01:01:50,780 --> 01:01:55,260 Mike Scharf: Yeah, IRAC is I-R-A-C, the Insecticide Resistance Action Committee. 681 01:01:55,660 --> 01:02:01,760 Mike Scharf: And that's, so all of our manufacturers have representatives who are part of IRAC globally. 682 01:02:02,700 --> 01:02:10,560 Mike Scharf: and they come up with different mode of action classifications that can help you decide how to rotate products. 683 01:02:10,990 --> 01:02:21,360 Mike Scharf: And so if you Google IRAC, I don't have their exact web address in front of me, but they have a really nice thing that they update 684 01:02:22,000 --> 01:02:29,599 Mike Scharf: once or twice a year with all the different chemistries available. So you can see the whole landscape of active ingredients available and 685 01:02:30,119 --> 01:02:36,099 Mike Scharf: you can get help there for choosing different modes of action to rotate through. That's one of their main functions. 686 01:02:38,260 --> 01:02:42,100 Dan Suiter: Another question here, Mike, you had talked about nicotinoid insecticides. 687 01:02:43,310 --> 01:02:45,520 Dan Suiter: One of the operators was familiar with the neonic. 688 01:02:46,400 --> 01:02:49,660 Dan Suiter: Is there a difference between the nicotinoids and the neonicotinoids? 689 01:02:50,340 --> 01:02:52,340 Mike Scharf: I think it's just terminology. 690 01:02:54,240 --> 01:03:01,460 Mike Scharf: They're pretty much so the nicotinoids look more like nicotine, which is what they were patterned after and 691 01:03:02,030 --> 01:03:11,100 Mike Scharf: then the neonicotinoids kind of they've evolved. They don't really look like nicotine anymore physically, but they still affect the acetylcholine receptor. Like 692 01:03:12,080 --> 01:03:14,540 Mike Scharf: Clothianidin is a neonicotinoid, whereas 693 01:03:15,540 --> 01:03:19,960 Dan Suiter: imidacloprid is a nicotinoid. I see. So nicotine is an insecticide. 694 01:03:20,580 --> 01:03:28,680 Mike Scharf: Absolutely. We can talk about what happened the first time we chewed tobacco or smoked a cigarette way back as teenagers. 695 01:03:31,200 --> 01:03:38,040 Dan Suiter: Yeah, I remember somebody at Purdue used to chew tobacco and put it inside of a jar and then put some caterpillars in there and it would kill them. 696 01:03:39,660 --> 01:03:41,080 Mike Scharf: It's dangerous stuff. 697 01:03:42,860 --> 01:03:57,780 Dan Suiter: Let's see here. Could you comment on the difference between the toxicity between, say you took the same active ingredient, it's typically more toxic via an oral route of entry, correct? As opposed to a contact toxicity? 698 01:03:58,440 --> 01:03:58,640 Mike Scharf: Right. 699 01:03:59,220 --> 01:04:08,520 Mike Scharf: So yeah, all insecticides are going to be almost in all cases more active by ingestion than they are by dermal exposure. 700 01:04:08,960 --> 01:04:09,980 Dan Suiter: And why is that? 701 01:04:11,580 --> 01:04:18,860 Mike Scharf: Well in terms of the insect, you know the cuticle, their outer cuticle, it's waterproof and it's got lots of layers. 702 01:04:19,859 --> 01:04:28,359 Mike Scharf: Whereas if you look at the gut, you know, I showed that picture of the gut, it's just the thin, the gut is a thin layer of cells and stuff as opposed to the cuticle. 703 01:04:29,119 --> 01:04:35,760 Mike Scharf: And in mammals, you know, our skin is an incredibly resistant barrier to insecticide. 704 01:04:35,820 --> 01:04:43,060 Mike Scharf: and toxins so just things are always more active by ingestion. And the final 705 01:04:43,280 --> 01:04:48,480 Dan Suiter: question here Mike and this is I think somewhat of a loaded question it the 706 01:04:48,620 --> 01:04:52,900 Dan Suiter: difference between repellent and non-repellent insecticides I don't I 707 01:04:53,020 --> 01:04:56,900 Dan Suiter: don't know that it's really that simple somebody here wants information on where 708 01:04:56,900 --> 01:04:58,060 Dan Suiter: they could go to find 709 01:04:58,680 --> 01:05:02,599 Dan Suiter: insecticides that are repellent and others that are non-repellent. Is it that simple? 710 01:05:04,140 --> 01:05:09,240 Mike Scharf: I think probably in the trade magazines. I'm thinking back to when the 711 01:05:09,240 --> 01:05:13,839 Mike Scharf: non-repellent termiticides first hit the market 15 years ago. 712 01:05:14,319 --> 01:05:18,559 Mike Scharf: There was a lot of talk about that and I think the real distinction there is 713 01:05:18,700 --> 01:05:25,180 Mike Scharf: pyrethroids and everything else. Pyrethroids are like pepper spray to insects. 714 01:05:26,020 --> 01:05:30,400 Mike Scharf: All our other actives are not detected nearly as much. 715 01:05:30,740 --> 01:05:30,920 Dan Suiter: Yeah. 716 01:05:32,110 --> 01:05:34,260 Dan Suiter: I have one final question here, Mike, before we let you go. 717 01:05:35,710 --> 01:05:41,000 Dan Suiter: So the essential oils seem to have really, you know, the whole green revolution here over 718 01:05:41,000 --> 01:05:49,040 Dan Suiter: the past several years has really kind of taken off in terms of use of 25B exempt actives, 719 01:05:49,280 --> 01:05:51,800 Dan Suiter: you know, rosemary and spearmint and cedar, that kind of thing. 720 01:05:52,120 --> 01:05:52,200 Dan Suiter: Right. 721 01:05:52,250 --> 01:05:54,100 Dan Suiter: Can you comment on kind of... 722 01:05:54,320 --> 01:06:00,040 Dan Suiter: Have any ideas on why that's happening in terms of, I guess you don't have the registration 723 01:06:00,400 --> 01:06:04,440 Dan Suiter: cost for one thing, but there seems to be a lot of products that have a lot of those 724 01:06:04,660 --> 01:06:05,520 Dan Suiter: essential oils in them now. 725 01:06:05,760 --> 01:06:07,780 Mike Scharf: Right, well, consumers want them. 726 01:06:08,120 --> 01:06:12,820 Mike Scharf: You know, the customers are, they have the ability to learn about these things more and, 727 01:06:15,000 --> 01:06:19,320 Mike Scharf: you know, so there's the demand, I think, is what, probably what it comes down to. 728 01:06:20,619 --> 01:06:21,920 Mike Scharf: They can be effective. 729 01:06:22,410 --> 01:06:23,660 Dan Suiter: Yeah, they're very good repellents. 730 01:06:23,660 --> 01:06:25,020 Dan Suiter: We've done a lot of work with them on ants. 731 01:06:25,030 --> 01:06:25,859 Dan Suiter: They're very repellent. 732 01:06:26,300 --> 01:06:26,740 Mike Scharf: Right. 733 01:06:27,240 --> 01:06:29,060 Mike Scharf: They smell nice sometimes. 734 01:06:31,140 --> 01:06:33,680 Mike Scharf: You get aromatherapy in combination with... 735 01:06:33,680 --> 01:06:33,760 Dan Suiter: Yeah. 736 01:06:34,550 --> 01:06:36,200 Dan Suiter: Your house can smell like a peppermint candy. 737 01:06:37,880 --> 01:06:42,820 Dan Suiter: I think that's about it Mike we really appreciate this I've seen this is 738 01:06:42,920 --> 01:06:47,000 Dan Suiter: something the industry just doesn't get enough of it's a and you really have put 739 01:06:47,000 --> 01:06:51,980 Dan Suiter: this together nicely it's from from A to Z here it's really nice so we appreciate 740 01:06:52,040 --> 01:06:55,900 Dan Suiter: your time and thanks everybody for paying attention again don't log out 741 01:06:56,400 --> 01:07:01,260 Dan Suiter: we're gonna take a five-minute break now and get ready for ants and appreciate it 742 01:07:01,400 --> 01:07:06,220 Dan Suiter: Mike and we'll see in a couple weeks yeah thanks Dan thank you everybody