welcome to the science for the public lecture series science for the public is an organization committed to bringing science information and issues to the general public this is our website for our program handout we are very pleased to be here on earth day and happy earth day to you this is the day that commemorates the beginning of the environmental movement in the united states some forty five years ago i'm finding that hard to believe in the early days of that movement decades ago it was easy in some areas of the mainstream to dismiss environmental concerns as expression of a sort of a fringe group of hippies and  but today environmental issues are very much front and center we now understand that the world is awash with toxins produced by humans and the central issue is whether organisms will be able to adapt fast enough to unnatural toxins in a rapidly changing complication of global climate some species adapt others struggle and still others become extinct and to learn and in addition to extensive research on familiar toxins things like p c bees and others she has investigated an emerging group called nano chemicals and i hope she'll come back and talk to us about those in the future along with her work as a consultant doctor monis and is an adjunct professor at the university of massachusetts and hearst and an independent scholar at the ronan institute most important of all she is deeply committed to making the complexities of environmental toxins accessible to the general public she's the author of two excellent books on the subject evolution in a toxic world she'll show it to you and  evolution i'd like to point out these two books are published by island press a nonprofit highly respected press devoted to environmental issues these books are available in the minuteman library system and they are must read for anyone concerned with how life has adapted to various toxins and how it might adapt now and now it is a great pleasure to welcome  and thank you for that really nice interjection and thank you all for being here on this earth day and you ask that i say a few words before i get into the really fascinating this is a great opportunity for me to talk about two fields that i think are fascinating which is toxicology and evolution and putting it together it's just been great as she said i there's you know it was so interesting to me that i actually did two books on it so but before i do that if an acid i say a little bit about what toxicologist do because she said you know a lot of people don't know what toxicologist do so basically toxicologists or people who are fascinated by poisonous chemicals and how these chemicals interact with living systems and i think a lot of people are probably familiar with toxicologists now compared to when i went to school because of shows like c s i in x files i get my hair cut the other day and the woman was like what do you do and i said i'm a toxicologist she said who do you work with dead bodies and so i say well you know maybe dead mice rats and fish or something like that you know so a lot of talk the majority of toxicologists are doing environmental toxicology so we study the effects of chemicals that are out in the environment how they interact with living systems out there and then a lot of toxicologists are working on to protect human health looking at  the chemicals in food and drugs and consumer products so you read about a lot of that in the news off in the what they found so in a nutshell that's basically what toxicologists do and why we do toxicology because we just sort of like to think about poisonous toxic chemicals but what i want to do is just give you a very brief background on some of the things that we think about when we're thinking about toxic chemicals so one of the first things that we're we need to think about is absorption ok these are sort of the four basic components that any toxicologist kind of should have running around in their head no matter what they're doing or what level they're working on so the first thing is absorption so how does a chemical get into the living system whether it's a human body or we're talking about a bacterial cell so you need to think about can it get into that because if it can't if it's sitting on a bottle or just sitting on the top of your skin and it's not going to get in it's not a problem not going to be toxic to you right so that's the first thing  absorption can that chemical get into the system that we care about the next thing is what happens when it gets into the system so does that chemical distribute throughout the system and where does it go so if a chemical comes in  out probably not a problem if it comes in starts to distribute throughout the bloodstream might get to your brain might get to your liver or bones or wherever then that starts to you know help a toxicologist figure out where they should start looking for adverse effects or how that chemical might cause bad consequences so absorption is the next thing and then this is this is the part that i think a lot of toxicologists are working on and think is kind of the most interesting part is  metabolism so once a chemical gets in it distributes throughout a body then what happens to it does it do you have enzymes in proteins do they interact with that chemical and how do they interact with it so you often hear about things getting metabolize  there's a huge feeling toxicology about detoxification we have a lot of enzymes proteins that interact with chemicals that are able to detoxify these chemicals they either break them apart or they add things to them that make them easier to excrete or to get out of your body so it's this really amazing detoxification system and so there's a lot of different kinds of detoxification different kinds of enzymes that do this so it's it's really sort of a focus of a lot of work that people do and then the last part is that we think about is excretion so once a chemical comes in and gets distributed it might get metabolized it might get broken down and then it doesn't get  and in what form does it get excrete it so sometimes they don't get excrete and so when we think about earth day you know some of the chemicals that really set off earth day that rachel carson wrote about were those kinds of chemicals that really didn't get excrete did very well they kind once they distributed in the body they got into the fat and they sort of stuck there and they didn't get out of a body and so that caused a lot of problems especially when that happened in the environment so we think about excretion so these are sort of the four basic things the toxicologists are thinking about when we're doing our work absorption distribution metabolism and excretion and so i did a lot of teaching and i did a lot of writing about this and eventually one thing that we don't think about often is evolution so i started thinking you know as i was trying to explain these things to students and you know readers i was thinking well it's really cool that we have this detoxification system we have all these different we have skin that can keep chemicals out we have all these things but you know how did how did these evolve so what with where this sort of conditions where see where life evolved some of these amazing kind of protective systems so this is what got me interested in evolution and so going to talk about for the rest of this talk start talking about evolution in sort of toxicology in an evolutionary context before i do that there are sort of three kind of basic principles for evolution so before we think about you know evolution we need to think about genetic variation so for evolution to happen we need to have genetic variation if you had one population within your population no variation you can't have evolution happen the next thing is that that variation has to be heritable you have to be able to inherit any kinds of changes ok so if it's not heritable if you don't know evolve some kind of cool third hand that can or i mean you're born with some kind of cool hand that can do great things and it gives your great advantage well if you can't pass it off to your offspring it's not go matter in an evolutionary context so it has to be you have to have variability in your population has to be heritable and then the last thing that we need is some kind of selection this is a box of chocolates by the way just to show selection but we need selective pressure so you need to have something that will cause some kind of difference in the survival of those offspring that have inherited that genetic variation ok so you need to have some kind of environmental pressure so it could be a change in climate change as climate changes the that have genes that might confer some kind of advantage might do better it could be hunting and fishing pressure humans actually have changed have you know influence size of fish populations or horns and sheep because of hunting pressures or it could be toxic chemicals so that's going to get to towards the end of this talk is how we influence that process with the toxic chemicals but i'm going to begin with how life evolved in a toxic world so taking a very long view so we think about our planet we're just talking about movies that have you know science fiction movies but you know we're living in a science fiction movie earth is a pretty toxic place if you landed here from another planet and hadn't you know had this long evolutionary history here this would be a nasty place in so if we think about earth me think about the very beginnings billions of years ago when cells were just beginning to come together and forming  earth the conditions were really we have a planet we had a planet we didn't have oxygen right there was no oxygen three point eight billion years ago three point five billion years ago when life was first taking shape and without oxygen there was no ozone layer that ozone layer we all know that ultraviolet light can damage d n a right so ultraviolet light is very toxic and there was less protection so back on early earth ultraviolet light was incredibly intense far more intense than it is now and so if you think about early cells trying to survive you know their d n a was at risk from ultraviolet light if we move up a couple of billion years earth cells start acquired the ability to photosynthesize and produce and as a result oxygen became a waste product ok so back then oxygen is a toxic and right oxygen is toxic people take antioxidants because you're worried about toxic oxygen oxygen radicals reactive oxygen can be very damaging to your cells so oxygen was a problem and it's said that you know back then that when cells started producing oxygen that was one of the first pollutants produced by living things earth became polluted with oxygen from all of these little cells that started photosynthesizing and releasing oxygen is a waste product so oxygen is toxic and then if they move up billions of years millions up to about half a million years ago i mean half a billion years ago five hundred million years ago when plant when trust plants started colonizing the earth if you think about plants plants trustor plants were rooted right so they couldn't go anywhere so one of the things that plants started doing for a defensive mechanism is that they eventually they evolved nasty chemicals everybody knows plants can have plenty of toxic chemicals in them we can't just go eat any plant because some of them are going to make us sick so plants are very well known for having lots of producing lots of different out the lights we know some of those toxic chemicals as drugs we harvest them for drugs but plants produce a lot of really nasty chemicals and so you know to protect them against predators  animal predators insect predators so plants are pretty nasty so you so it's a nasty place but fortunately evolution is amazing and so if we go back and we think  about one of the things i did in these the things that i wrote about in that first book so these two slides are really that whole first evolution in a toxic world into slides but you know we go back to the very origins some of the the earliest cells on earth had an enzyme called d cells protected them against ultraviolet light and almost every living thing today still has an enzyme just like that so it's called highly conserved just about every living thing except for placental mammals which is a long story which i won't go into but it's really kind of amazing that when oxygen started flooding into the atmosphere well how did cells survive because now all of a sudden we have this toxic oxygen back then everything is anaerobic it didn't like oxygen oxygen was bad but now most of the things on earth or in animals are robotic right we actually need oxygen how did this happen so over time life evolved enzymes that could detoxify oxygen catalysis one super oxygen oxide dismuke tases another a life of all these enzymes that could detox if i oxygen diffuse the toxicity caused by reactive oxygen species and we still benefit from those today we go exercise when you're just breathing anything you do you have these enzymes sort of in the background something up the reactive oxygen species that your cells are making as you breathe as you just do anything so these are really critical highly conserved and times also and then finally in response to a lot these plant toxicants there's a whole family of enzymes that detoxify a lot of the lot of plant toxic and a lot of plant poisons they also are involved in a lot of drug metabolism because a lot of our drugs kind of come from  plants and so when i said that toxicologist tend to be very interested in metabolism a lot of times they're studying these kinds of enzymes it's a whole huge enzyme family and here i just showed there's a really interesting story about queen  that we depend on for detoxifying even things like metabolize things that we take like tylenol alcohol lots of things so so there's this is just an example of just three of those detoxification mechanisms but the idea was to get people thinking about there are a lot of these naturally occurring toxicants and over the course of evolution millions of years billions of years hundreds of thousands of years life evolved in response to these pressures caused by these naturally occurring toxic chemicals and we have this amazing detoxification systems but we all know that the problem today is that a lot of these systems have become overloaded and they're being exposed to chemicals that they didn't evolve in response to so here's a quote from rachel carson which seemed appropriate today the chemicals to which life is asked to make its adjustment are no longer merely the calcium and silicon copper and all the rest of the minerals washed out of the rocks and carried in the rivers to the sea they are the synthetic creations of man's inventive mind brewed in his laboratories and having no counterparts in nature so back then this was sixty two when rachel person said this you know life  all these systems to have to basically detoxify chemicals but what about today so this is what i want to talk about next and i'll spend the rest of the time talking about what about today in response to the chemicals that we produce today so here we are in is mentioned we have p c b we have lots of pesticides herbicides and even antibiotics is a toxic and to bacteria right so these are the kinds of things that i focused on for the second part and asked you know can can life evolve quickly in response to these kinds of chemicals because what we know today what i just talked about was sort of taking the long view and talking about evolution over long periods of time but increasingly evolutionary scientists are understand that life can also ball very rapidly and we're not talking about the evolution in terms of the evolution of different species we're not talking about the evolution of a whole new enzyme or a whole new protein but we're talking about very small changes to some of these proteins and enzymes it's still evolution because their whole population changes in response but we're talking about small changes and they're they're small changes but they can have very big consequences so this is the topic of that second book which is a natural selection our changing life change by gene so i'm going to begin with bioethics because i think this is something that everybody is familiar with and if people haven't had their own experience with antibiotics and antibiotic resistance they probably know somebody that does there are it's a huge problem i was just talking with  about this earlier but antibiotic resistance if you just have to read the news these days or listen to the radio or you know that antibiotic resistance is increasingly becoming a big problem and so each year in the u s and you probably might have even seen these numbers i don't know how many times i've seen them when you just look in the news but there's two million cases of antibiotic resistant infections each year and twenty three thousand deaths in the u s from antibiotic resistant bacteria so these were diseases that were once curable with antibiotics how did we get here so before i go into sort of the evolution part i always think it's important to think about the chemicals that we're producing why we're producing them and how important they may or may not be to our lives and so antibiotics we all know are really very important these are some of the founders of very important scientists that were involved in the develop development and discovery of antibiotics they were working they were working in the early one thousand nine hundred eighteen ehrlich was one of the first to just after the discovery that bacteria actually cause disease he was working with the dye industry and he wondered that if you could at that time you could actually stain bacteria in see them because if you guys if you've ever done like cheat scrapings or try to look at cells in a microscope you know they're clear they're very hard to distinguish from your own cells but but back then someone had figured out that you could actually die the cells in stain them and then you could see them and distinguish him from human tissue in so early wondered well if you can dye cells in stain them and see them could you poison the cells with the dye so if you had some chemical that specifically sought out those bacterial cells why not try to aim at them with that these were two scientists that had also served in world war one and they saw frontline they saw many men die from their injuries that were in the leg injuries themselves weren't life threatening but the infections that followed were and so this these people are living in a time when people die of infections and i think it's hard for all of us to realize this because it just doesn't happen anymore but before antibiotics people died from stephan strap in infections that we just think of today is curable so don't act came back from over one and he wanted he was also determined to sort of pick up where ehrlich left off and discovered dies that could cure that could kill him to bacteria he did he discovered sulfa drugs which we still use problems with infection and the diseases in the death and destruction that they caused so he used looking into sceptics and his is the story of that accidental discovery that everybody might have heard of already but fleming was you know he had place full of bacteria he was going off for vacation so he left his aggro there agger plates that have sort of a lot of bacteria on him he left his place for vacation he went away he came back and he noticed that there was this mold growing on the plates which isn't unusual if anybody's ever work with bacteria you know that mold lands on plates and it grows but what he didn't notice was that there was this clearing in the bacteria and somehow that that mold was sick creating something that was killing the bacteria and so he had the insight to follow up on that and of course that was penicillin so he discovered penicillin and that was really became the kind of wonder drug the miracle drug in sulfa drugs and penicillin were very important during world war two for saving many lives and then they became very popular antibiotics in so fleming won the nobel prize along with two others that helped sort of get moved penicillin from the laboratory into the market and make it make it in enough high enough concentrations that people could use it but he realized early on that there could be a problem with using too much penicillin and he said i'd like to sign a note of warning is not difficult to make microbes resistant to penicillin in the laboratory by exposing him to concentrations not sufficient to kill them in the same thing as occasionally happened in the body so he he knew that bacteria could evolve resistance and he was worried about this this was back in one thousand is a long time ago and apparently nobody listened because here we are today with big concerns about antibiotic resistance and it's not just to penicillin it's just about every antibiotic that we have how does this happen so if we go back to sort of the basics of evolution and we talk about genetic variation how in the d n a opens up it replicates and you get two strands of d n a the should be identical to each other this should be identical these two should be identical but every once in a while a mistake happens and that mistake is a mutation sometimes mutations are corrected and sometimes they're not if they're not corrected they just get carried through to the next cell and then you end up having what's called a daughter cell with a mutation sometimes these mutations actually most of the time these mutations don't do anything they're new they're called neutral they have no effect there's just they're carried through no big deal sometimes they're lethal in that cell won't go on and where very occasionally they might be beneficial and they can happen in bacterial populations so in now if you go back and we talk about mutation in bacterial populations here we have a bacterial cell bacteria bacteria just divide into that's how they reproduce so this bacteria divides in two and a  pop up and it gets carried through the population here is a there's no mutation here so you end up with a population of bacterial cells some of them have this mutation some of them don't no big deal that area whether it's or whatever you might have is just doing fine pumping away reproducing and so you get this genetic variation in the population but maybe you don't feel so good and so you go to the doctor and the doctor gives you an antibiotic and what happens is that the antibiotic just so happens that these cells with no mutation are sensitive to that antibiotic but maybe that mutation made the cells resistant and if it does and you're exposed to antibiotics that you've changed their environment you've caused some selection pressure and you end up with a population of cells that are resistant to that antibiotic and then those cells go on and if you pass them on to somebody else that somebody else gets antibiotic resistant staph or strep this could be a mutation that happens in kind of real time while you're exposed to that or it could have been what people have discovered with it with bacteria which is really kind of distressing is it could have happened millions of years ago so a lot of these bacteria tend to have resistance genes that must have evolved hundreds of thousands or millions of years ago and if you think about it it might make sense because here we're talking about penicillin a lot of our antibiotics are from living organisms and they all live together in the soil so it's possible that millions of years ago they're all being exposed to some of these different chemicals and they just happen to carry these resistance genes with them this is called standing genetic variation but the one other thing about bacteria that makes them particularly tricky when it comes to resistance in concerning so this is called vertical transmission of genetics that we do we have vertical transmission we we have our offspring vertically we don't give our genes to our sisters or to our friends but bacteria can so they can actually transfer their genes to other bacteria through these little bits of d n a called plas and so they can transfer bacteria in their resistance to bacteria that are related to them and so this is one of the concerns about resistance because when they talk about resistance and one kind of infectious disease there's the potential that that resistance gene could be passed on to a different kind of pathogen and this is part of the reason why there's so much concern about resistance being in just you know when you hear about multi drug resistant bacteria you hear about bacteria that are becoming resistant to all antibiotics and there's big concern not just for those pathogens but because now those genes are kind of out there so if we go back to their original thinking how did they get resistant what was and what are the mechanisms what it what what changed in those bacteria that made them able to handle these new chemicals that are coming into their there can be say they can produce multiple copies of a gene that might be a beneficial gene some cells have pores that help to pump out toxic chemicals well what if they increase the number of those poor as then they get better at pumping out toxic chemicals target site modifications so a target site means when you make an antibiotic or a chemical that is going to kill something right you have a target in that chemicals are going for that target well if the target changes just a little bit in the chemical can no longer interact with that target well that organism now can be resist that chemical so there's there's a lot of different ways that living things can sort of resist and evolve resistance to toxic chemicals  and it goes back to sort of the some of the basics there just sort of tweaking those basic systems that have evolved over a longer periods of time so what do we do so i think that with antibiotics and just about everything else everybody has probably knows the answer because we hear about it a lot but we can't do anything about genetic variation especially the bacteria it's already there we can't do anything about the inheritance you can't can't stop them from reproduce well you can't stop them from passing their genes on if they reproduce what we can do is lay off on the selection pressure so there's a lot of talk about how do we change how we you know back when my kids were young if i walked into the doctor's office with they had a ear infection or a little temperature i walked out with a mock cicilline that just doesn't happen i don't think so often anymore usually they want to know that it's a bacterial infection that my kids could have been in viral infection which antibiotics don't help against so now they're much more careful about giving out antibiotics there is a lot of just there's a lot of new discoveries that are coming along new there's certain kinds of anti bacterial chemicals that can kill very specific bacteria and not kill sort of all bacteria because a lot of antibiotics are called broad spectrum or nonspecific they don't kill all bacteria but they kill a lot of different kinds of bacteria and so that's a problem because you've got you're exposing bacteria that don't need to be exposed to that chemical to antibiotics so that the biggest thing we can do is really is reduce the pressure reduce that selection pressure and there are studies that show that when you do back off that the sensitive populations begin to emerge again because maybe there's a tradeoff maybe the resistance genes also made them not so fit so if you back off sometimes the sensitivity comes back and that's a good thing ok so now i'm going to switch gears a little bit so that was the sort of very fine and in moving on to weeds in herbicides in agriculture tell similar story to begin with what are we dealing with so we'd share excellen subjects for the study of microevolution that's i'm talking about remember i said i'm not talking about evolution of new species or evolution of new proteins or enzymes we're talking about little tweaks to proteins and enzymes and we're talking about very small changes and in in quick time and this is microevolution  herbut baker was an evolutionary ecologist and he also wrote about weeds and what he knew about weeds we know today too is that weeds are really good subjects for this because they are great they're very prolific they produce lots of seeds they might reproduce many times a year they're not so picky about where they live so they're just there i mean weeds or weeds there they've got a lot going on and they tend to be very diverse and they have the potential for a lot of genetic diversity so we are sort of a powerful little things and then if we think about agriculture what have we done artificial this is wilson in one thousand nine hundred three artificial selection has always been a trade off between genetic creation of traits desired by humans and an unintended evitable weakness in the face of natural enemies so when we breed crops for the traits that we want the characteristics we want we've basically turned them into pets they're they they need care they can't really care for themselves and we also as i was talking about yvonne earlier you know she was men she monarch culture you know we plant very large swaths of these crops which just kind of invites attack by pests so we've created this system where we need to help agricultural crops and we do this with herbicides there are there at least a hundred different kinds of herbicides but that's not enough one of this is one of the herbicides that and you talk about carcinogen so but it had been considered one of the fairly kind of safer herbicides for many years and so month santa sells millions of dollars a year of pesticides  mostly roundup so it's big business how did we get here how did roundup become this very popular herbicide it was discovered back in the  maybe the seventy's john fronts by john france and it when it turned out it was a really effective herbicide and it was effective because it basically kills anything green and growing and so what it what it allowed farmers to do was to just kind of burn down crop it helped create the no till agriculture so because if you could just burn down all your crops with the herbicide or all the weeds in the crops before you plant then it pretty much went away then you could plant again and you wouldn't have to worry about killing and disturbing the soil so in that sense it was considered a good thing and at around the same time or a little later p if we could we have a herbicide that is incredibly effective but what if we could make a plant that could grow and be resistant to that herbicide so then we could apply it even when the plant was growing it would kill everything else we want to have any weeds that the plant will do just fine it took many years but they eventually did it and roundup ready soybeans were developed in produced and i believe the ninety's that was the first they also produced corn cotton canola alfalfa and beets so this is to say that there were a lot of roundup ready crops that were being produced one of the special things and one of the reasons they did this is because they thought that it would be very difficult for anything to evolve resistance to round up it took them a long time to develop their own roundup ready crops and to find a gene that could that could be implanted into plants and that could confer resistance and it was very hard to find th so the thought was it just wouldn't happen in nature it would be hard to happen you know for that to happen but once they started producing all of these roundup ready crops think about that selection the box of chocolates and the environmental pressures it created incredible pressure on the weeds because so back in one thousand nine hundred six before these crops were everywhere they sold one hundred eighty million pounds around up there are now projected to be selling in the millions of metrics of tons of rondo the case that that pressure increased incredibly as farmers start using roundup after round up after round up on their crops and what did  they get roundup resistant weeds all over the place this is map from dr kevin bradley from the university of missouri just this is twenty thirteen and it would probably look at different now but it just shows the number of different kinds of weed that are agricultural important that are resistant to round up run to preserve since it's a really big problem for agriculture they've got these roundup ready crops so they're using the roundup and now they've got round a pretty roundup resistant weeds it's not just round up like i said there's one hundred different herbicides there's two hundred different herbicide resistant weed species and sixty million firms across the us have resist s problems with resistant weeds so it's a big deal and again solution you know for the last ever since we had pesticides and herbicides we've been we've been at war with nature and we've been relying on chemicals to beat down the pests in the weeds and we're now realizing that this isn't the best solution because nature wins weeds evolve resistance and so we need to figure out a way to turn down the pressure to use less of the herbicides and to figure out how to farm that way the last thing i want to talk about is one of my favorite subjects which is bed bugs so i usually ask if anybody's had bed bug problems in the audience and usually when i do this it's the young people the college students and the graduate students that have had  come back and they're of course resistant to some of the pesticides that we use how did this happen well we can go back to the early days of paul miller who discovered d d t or didn't discover it he discovered that it's a very good pesticide he was in he in what he found was it was incredibly good at killing houseflies d d t became the go to chemical d d t was sprayed everywhere and anywhere for the book i interviewed claude boyd who was an ecology graduate student back in the sixty's and he said you know that there was a culture of using pesticides everybody knew they were probably using too much but nobody wanted to stop he was in mississippi mosquitoes were a big problem back then in d d t was a savior he said you know they would spray it in their house they would go out gets america let it settle and come back in there was a radio station d d t so it was a big deal and by the one nine hundred seventy three over a billion pounds of d d t were used and of course this is this is where rachel carson you know really wrote about was the d d t and the environmental problems caused by e t not and she did mention resistance but beyond resistance the problem was that it accumulated it didn't go away  cause problems for raptors and other animals but you know it's not just d d t if this is a chart from a book about evolution is a very good textbook are and it's this is just showing resistance to pesticides and houseflies over the years and as you can see they've they're pretty good at resisting pesticides there's a lot of different pesticides here this arrow is when resistance was first detected in this is when the population was pretty much considered resistant in the chemical wasn't useful against them ok so here is d d t but every other chemical that's been used we have a resistance problem here is rachel carson again darwin himself could scarcely have found a better example of the operation of natural selection again years ago decades ago she was talking about this yet we continued nobody was talking about this in terms of you know what do we do what should we do how do we stop this from happening so i in again the answer is the same as always we need to turn down the pressure so i talked about just bacteria weeds and insects this happens this is cross the spectrum of life i could have talked about viruses in evolution in response to antivirals cancer cells in response to chemotherapy fish fall and fish and fish and birds and salamanders these are evolving in response to pollution to chemicals like d d t n p c bees in mercury this is kind of amazing that sort of like evolution out in the wild so a few questions about that i can answer that afterwards and then there are questions about whether humans are evolving most likely so the problem is as you can see is that those species that are evolving in response to the toxic chemicals in our surviving are those that are like weeds bacteria insects things that are very prolific short lifespans evolve rapidly the fish that are evolving are similar to that they they have short lifespans they are pretty prolific so it's those of us who live longer have longer generation times we're kind of out of luck so just the take home message here is that we influence evolutionary processes with our chemicals and that evolution is is really is relevant in our everyday life and i think we just don't usually think like that but evolution can impact us in big ways that we don't always think about so that's it and i just like to say thank you to first of all island press which is i've written the books with island press it's a great press to work with and they're very supportive of sort of books that make a difference in they they really have been great to work with so this is the this is the new but this is the rapid evolution in sort of the a book written for the general public in general readership this was more written for toxicologists evolution talks world that was the first two slides that i should that sort of why we should think about this that i need to think my husband and my friend penny because they were always my friend penny was my a p biology buddy and she is now an immunologist and she has read every single page that i've written and reviewed it as a scientist so valuable my husband who's also a scientist has read much of what i wrote and my dad who has encouraged me to write and i always said no no no scientists don't write so i didn't start writing until i started doing these books which is only a few years ago and then the impact you mass department environmental conservation where i'm an adjunct for the access to their library which i would with the library access in their database i wouldn't be able to do this so that's it thank you that's a really interesting question because there are i would probably say i do doubt it but i don't know i don't know if anybody knows so bacteria are in the environment there are lots of examples where bacteria have evolved resistance or or even turned nasty stuff into food sources that's actually i think when months into discovered the gene for life is a resistance or roundup resistance they were hoping to find bacteria and they found it in a bacterium that was in waste puns that that could really do this response that had roundup in it and they were hoping to find a gene that in bacteria that could degrade the stuff and clean it up so there's a lot of examples of that so i never really thought about it like in our bodies which you have that  we are we are i don't but you know you have to think about it so you have to think about that absorption distribution excretion that kind of thing and so those bacteria that are out in nature that evolve resistance and things like you know to mercury or even to p zur that can you know detoxify those those are constantly exposed to those kinds of chemicals and so over the years generations have become resistant you know it's a very interesting question  guess would probably be not but i don't know and usually often when bacteria are evolving resistance those chemicals are in really high concentration so in the places that they degrade chemical toxicants in the environment often it's where the chemicals are hotspots so they're actually i might say this wrong but i think in some places like there might be bacteria that could say metabolize  help change p c b s d in detoxified not necessarily detoxifying but alter them but it tends to be work p c these are really high so we thankfully don't have that situation in our bodies even though we are exposed to lots of different chemicals so it's interesting question but again of course that is another downside of antibiotics is that we're flushing out a lot of the beneficial bacteria and nobody really fully understood that until only recently so that's another reason to back off of antibiotics and to think about how we could treat disease differently if we think about it more ecologically it's the same thing out in the farm fields too we need to think about things that are more ecologically in the whole system rather than just taking care of one kind of cr then years ago i guess i'd heard about it so you know one of the problems is often they're feeding fish fish so they're taking fish from the wild and they're feeding the farmed fish if that's how they got that way and so then it's  magnification problem so you're kind and sometimes they're feeding him fish oil or they might be trying to you know concentrate it and a lot of the chemicals that tend to be the problem chemicals like the organic clarions like the p c b and the d even though there is called legacy chemicals because we don't produce them and release them well not here anyway anymore those concentrated in the fatty tissue and in the fats so in oil would be the worst thing for those kinds of chemicals other chemicals tend to be in the muscle so anyway they're feeding you know i thought that that now that they would test the fish or that they're feeding to accurate agriculturally grown fish or aquaculture  if it's the case that's how i think it probably gets there if it's from the food it's because they're taking fish in the wild those populations tend to have chemicals in them still and even if they're small fish if you feed enough a small fish they can accumulate  sufficient concentrations to where they're a problem so what happens to us you know it depends on the chemical but i think there's plenty of studies that show that we have lots of different kinds of chemicals in us including some of the ones that you would you know little small concentrations of d d t xin other kinds of chemicals that you would be surprised that we have in us in it could be from just being exposed through either eating   one way that they get out of a body is they go out with the fat so when a woman is lactating milk is fatty these chemicals go out in the fat in for wild animals it's a problem especially if  produce eggs eggs are very fatty so these chemicals go in the fat female fish tend to sometimes once they spawn because they have they spawn a lot of little fatty eggs so they're basically dumping all their their organic lorien or fat accumulating chemicals into their eggs in so they will have the reduced their own load of those chemicals and it will come out into the eggs and so then the most vulnerable population the young fish in young kids if it's we're talking about  exposed to the chemicals yes oh yeah yeah and i think it's just i think it's changing now with it's actually this is one thing that bugs me we tend to just be black or white you know we go to one all in one way or all the other so now there's all the stuff about the micro biome and now they're like making micro the micro biome is all the bacteria in your body and in your body and you know some of it's beneficial a lot of it's probably beneficial or just sitting there not doing anything and not pathogenic and now everybody is like you know get micro biome spray you can do all the stuff so but somewhere in the middle it yeah so even you know it's true it's cut so we're starting now to think oh maybe bacteria aren't that bad and it will be the same thing that oh so bacteria in the environment maybe they're not that bad because people realize that the environment is loaded with bacteria and always has been not just bacteria but fungus and viruses and protozoa and all sorts of little things became it see the world is crawling with it and we've lived with it but we you know there's all this new thing about our over h and we're just too clean and we just do too many things that you know are just our own microbiome so but i think in the environment too it's a it is people squeamish like over squeamish about these kinds of things but in bahrain mediation it's a big deal i mean bacteria are great for cleaning up a lot of the messes so they're important and they're useful and there is i think there's a big pretty big business though of trying to get bacteria you know that are able to clean up a lot of the toxic waste sites or at least reduce the house or not completely clean up so but that's a good point yeah it's concept it's just how we think about these things so we need to change but i think that's happening now that right now we're like all in the ok well you know bacteria are great and they'll do everything everything is caused by bacteria and we'll probably find out how important they really are but you know somewhere there needs to be some moderation so so what do we do and one of the things that i want to learn about more and write about is that concept you know if if the the big users of g m had been as you say socially responsible all for the good would we think about them differently i think there would still be people who are concerned about them but i think it wouldn't be the same pushback as there is when we've got these you know this kind of cropping system and they produce more cropping systems and i think even some of the early scientists that might have supported the use of roundup they supported it with the notion that it would be it that there'd be crop rotation with things that didn't use round up but it didn't happen that way so yeah i totally agree and i think that's a really interesting point and it's something that i'm looking forward to really digging into the interaction these different chemicals because the way to toxicology is a field of all business is studying one chemical in one system at a time and it evolved in that way because it's really a regulatory and applied field and so the regulators needed numbers and they needed to control these single chemicals in part that got left out is the realization that we're exposed to lots of different chemicals so whenever there is like water quality criteria it's first single chemical it's not for the twenty different chemicals so what happens when th twenty different chemicals are all below the water quality criteria but you have a lot of them so to make up for that they're trying to do those sort of models to how to how do you know think about this there are new systems are called high throughput systems can you know sort of use very small amounts of chemicals look at him and sell systems running through computers that he could do lots of different combinations of chemicals but still that's at the cellular level so it's a really big problem in toxicology and even when people do these studies in a laboratory and in laboratory animals they can only really look at a couple of combinations of chemicals because you're talking about enormous systems to do that so it's a big deal in sort of you know people trying to modeling and computer competition all toxicology and all sorts of things and so that's another question sort of like a chimera one that i would like you know if toxicology had involved or came about it in a different way sort of in response to say maybe chemical mixtures how would the science look what would a look like as a science would be very different i think and so but it didn't and we can't start over but so we need to rethink how we do things or some things probably do need to start over but that's that's a good question and it's a big problem because i mean even i slip into that sort of talking about here all this single chemicals and really we're talking about chemical mixtures so when you're talking about resistance in chemical mixtures that's actually the one of the  solutions so you know when you get when people talk about chemotherapy often there's there's chemical cocktails antibiotic mixtures you know so there's just sort of if you if you throw a couple of different chemicals at a system it's unlikely it's less likely that they would have resistance to those multiple chemicals so in the same thing with pesticides and herbicides even talk about it and i think it's in the process if it hasn't been approved already i don't know where it's at but they call it stacking so you don't have just one a plant resistant to just one herbicide you have been resistant to two herbicides so that nearly so now you can beat off the resistant weeds by applying to different herbicides if it's resistant to round up you throw another herbicide at it in the plants can withstand it because you've engineer didn't resistance to both of those which seems like it will just create a bigger problem of more herbicide use and eventually i would guess eventually resistance will happen so i don't know what the fold is but it's increased a lot but i don't know what the fold is probably depends to what herbicide you're thinking of what you know what you're talking about one of the problems also with like life is say well now that life is safe as you know people are sort of rethinking it as the quote safest herbicide but now that there's so much resistance to it some of the older herbicides that fell by the wayside because they were more toxic coming back into use because i think they weren't creating lots of different herbicides because they had rhonda so the development sort of that's one of the problems with antibiotics too is that the development of antibiotics is sort of this started back in you know there haven't been a whole lot of new antibiotics very new very new you know totally different kinds not just tweaks  you know that but now hopefully we'd be smarter about it i mean i think he thinks he's yeah right yeah and so there's some you know i guess it would be the talk was that it would be difficult to resist evolve resistance but you know i feel like we've seen this over and over again they hurt they said that with round up  so better safe than sorry hopefully we learned a lesson we didn't learn it forty five years you know whatever seventy five what was it sixty five and learned nine hundred forty five yeah know i haven't seen that i would try to pry be the reverse because it's a bad thing to have but i have i did a little bit of writing about it a few years ago so my information and peanut allergies is a few years old but i think the thinking is part of it is could be the way we process peanuts it could be that we withheld peanuts i mean there's some research showing that very you know exposing young kids to very small amounts you know prevented or that there was a lower incidence of peanut allergies so i don't know where the research is now but i think so that is more just our behavior around peanuts and what we do with peanuts and how we've that might have contributed to that but there could be other things you know i don't i'm not up on it but i just know that we do we have change that you know there's the whole claim or you know so we changed a lot of things yeah there's all sorts of interesting studies that you know i don't know if they're just one off studies in the next study might show something different so that's where it's hard to just say oh yeah and there's this study exit was the one with the washing the dishwasher people who don't have dishwashers had like i don't know what it was less allergies or something like that too so that they were exposed to more stuff so you know you build up a different kind of system so i don't know because it allows research is really new and that's one of the problems is think in sciences that especially these days in writing about science there's a lot of hype in every article that comes out there's a lot of hype because it's a screaming headline and then two years later you know maybe a flip flops or it's wasn't that big a deal and then people kind of distrust you know it kind of builds distrust of science which is sort of a problem yeah thank you for your great idea