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    Atrazine And The Forever War On Science
    By Hank Campbell | May 7th 2014 11:47 AM | 14 comments | Print | E-mail | Track Comments
    About Hank

    I'm the founder of Science 2.0®.

    A wise man once said Darwin had the greatest idea anyone ever had. Others may prefer Newton or Archimedes...

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    I'll tell you up front, I am not a big fan of chemicals.

    It's not that I have chemophobia, or any science-phobia, I instead have that special sort of elitism that is available to people who have just been lucky enough to not need chemicals. I don't even like to take aspirin and I have that luxury because I haven't needed to take any drugs for a recurring condition, so it's really easy for me to embrace such naturalistic posturing. When it comes to food, if I had my way, nothing my family eats would be grown, processed, killed, cleaned or cooked by any hands but mine.

    Like most of you, I can feel that way because I was lucky enough to be born in one of the most agriculturally rich places on Earth. Yet I know the rest of the world is not so lucky. For the rest of the world, there is one great equalizer: science. Science can make things grow where they otherwise might not, science can prevent pests and weeds from ravaging yields on small farms.

    That's a good thing, and yet most people who benefit from it know little about it. And what they do know is scary.

     Hank Campbell

    Is there a war on science? Of course, there always has been.
    Shout out to Joe Haldeman.

    Where I live in Sacramento, one of the world’s most agriculturally knowledgeable cities and the capital of America's largest food-producing state, if I ask most people to name a pesticide, they can only name one - DDT. They don't know why they can name it, they can't remember Rachel Carson or "Silent Spring", they just know it must be bad because they have heard of it.

    That the only pesticide people know of hasn't been used here in over 40 years is a testament to the safety of modern science. In a vast, complicated narrative about science and our culture, where people assume if they have heard of a chemical, it must be bad, few people can name the two most popular herbicides that increase agriculture yields dramatically.

    Those two are glyphosate and atrazine. Glyphosate (e.g. Roundup – Monsanto) has been covered extensively on Science 2.0 and while environmentalists don’t like it - they don’t like any chemicals - atrazine is where the real cultural action is.

    There’s a stealth war going on over atrazine and, occasionally, as happened earlier this year, it breaks into open war and makes some mainstream news.

    Unlike most science stories, this one didn’t involve any science – it instead invoked a world of threats, sexual harassment, lawsuits...and rapper Tupac Shakur.

    *****

    A few months ago, a journalist in The New Yorker named Rachel Aviv wrote an article about a reproductive biologist who is convinced that atrazine, one of the most successful herbicides in history, is bad for us. It was good timing, because atrazine is undergoing a registration review with the Environmental Protection Agency. The EPA had also convened a special science panel on it in 2009 after finally completing its last registration review (done every 15 years) in 2006.

    Why does the EPA keep studying it? The easy answer is that is what the EPA does.  The real answer is a lot more complicated.

    The story begins with a 2002 journal paper that seemed to show atrazine had adverse effects on the laryngeal muscles of frogs – they were not developing properly and that impacts androgen and sexual reproduction. No calling, no canoodling – a real disaster for an indicator species like frogs.

    It’s unclear today what was really happening with those frogs. No one knows except the researcher who made the claim, Professor Tyrone Hayes of Berkeley. He refuses to share his data with anyone.

    Still, even without having any data, the EPA felt like it was a valid hypothesis. So-called endocrine disruptors have really diverse chemical structures and that can make it difficult to predict biological effects, but science knows a lot about amphibian biology by now, which makes frogs a good candidate to do that kind of risk assessment. And frogs are important.

    Syngenta agreed. That’s right, the company behind atrazine said it made sense to determine once and for all if their product was harmful to the environment.

    *****

    Fast forward to February of 2014 and that article in The New Yorker. The piece by Rachel Avivwas not about science or even health, it was more about what we in science media call The Myth Of The Oppressed Underdog - that journalistic narrative where some maverick beacon of truth is trying to fight an entrenched constituent, be it a company or science dogma. At the time, I was uninterested, for the same reasons I am not interested when some underdog claims in a media article that a diet plan can prevent Alzheimer's or that cold fusion is being bought by Big Oil and stuck in a warehouse to protect profits. It was an advocacy piece about a biologist trying to convince the world of something and she did a fine job. I recognize that modern journalism is often about telling a story rather than getting to the bottom of one.

    But I also recognize that journalistic advocacy is why a giant chunk of America no longer trusts scientists; in 2014, you can figure out the voting record of people by asking if they don't trust chemists or climatologists.

    This story predictably took hold with the political demographic that dislikes chemicals and agriculture and corporations. Suddenly Hayes was on NPR and Democracy Now and being quoted in various other outlets. People like to believe in vast corporate conspiracies and media outlets need a steady stream of content for their audience and so no one 'asked the awkward questions' of Professor Hayes about the claims of racism and threats and dirty tricks by Syngenta that he lobbed during his soliloquies. 

    But then Hayes said he had the science to back his beliefs about how atrazine was harmful to frogs. I actually thought that had been settled for years and so it got me willing to ask the awkward questions. You should too, because unlike claims about frogs being feminized and data no one is allowed to see, the EPA is on record saying the issue has been settled, and the data is public.


    Please get to the point. On a Terrorized Scale of 9 to 10, how scared
    do media accounts want us to be? Image link:jessandeeonline

    Journalists like to write about individuals rather than issues because writing about individuals is easy; just interview them and create a timeline and pick your hero and cash the check.  Issues are much harder because they require research.

    It turns out that if the issue is atrazine and public health, you can feel pretty safe.

    *****

    Atrazine is used to kill weeds, mostly in corn fields. Syngenta, its primary manufacturer, is big -really big, $14 billion - yet not so big that they can control where they show up in Google. If you search for atrazine, rather than get the actual atrazine site, the first entry is for Wikipedia and the very first citation in their entry is for that recent New Yorker article (as of April, 2014 anyway). Atrazine has been around since 1958 but the first citation in Wikipedia is a New Yorker article from February of 2014?  More strangely, that same article is cited three times before you even get to the table of contents.

    That a piece with no science is the very first citation for a product pushing 60 years old tells you one important thing -- there may be no health issue, but there is certainly a public relations one.

    Since the Wikipedia entry had clearly been hijacked by people promoting that New Yorker article and not science, I then went to Source Watch and other places that claim to find secrets - still no science but they assure us that Syngenta is not a nice company. I had saved the Environmental Protection Agency for last because I knew what I would find. They must really hate atrazine, I thought, they hate everything. This is the vilified government agency that had to be ordered by a Federal court to not blame fracking for environmental issues without doing a study, they declared water a pollutant when too much of it annoyed canoers, and they recently had to defend themselves against the charge that they do 'secret science' and don't disclose the methodology or studies related to greenhouse gas emissions.

    If they blame first and prove later when it comes to the environment, the EPA must have really hammered this atrazine stuff – they spent years studying it, they had to have found something.

    Well, they didn’t. Rather than a caricature of science like in the examples I listed above, I instead learned about one of the most rigorous environmental studies ever done. And it completely exonerated atrazine.

    Why didn’t the atrazine Wikipedia entry talk about that? It did, but only writing that the EPA study has "been criticized". What was the citation for that? The New Yorker article. And that old Bogeyman"industry-funded" was invoked about it - the source for that? Also The New Yorker article.

    Clearly, The New Yorker is far better at controlling information about atrazine than Syngenta is.

    Conspiracy stories about funding and secret deals mobilize activists but they are a head-scratcher for actual scientists. Scientists know something Wikipedia editors and advocacy journalists do not; studies are "industry-funded" because that is a legal requirement.

    All safety studies are industry-funded because if a company has to pay for studies, which can cost tens or hundreds of millions of dollars, they won’t keep developing a product they are not convinced is safe and effective. The EPA and the FDA and everyone else is right for requiring industry-funded studies because most people agree that taxpayers should not have to pay to find out if a product is safe or not.If a company wants to sell something, they should prove it is safe. 

    Credit: EPA

    In the case of atrazine, if you like irony you will like that the EPA told Syngenta they had to pay to try and prove their own product was harmful. The EPA was going to monitor the work and EPA got to pick the parameters and the methodology. The study was going to be duplicated and the results were going to be part of the public record, no matter how things turned out. How many journal articles that have a peer review stamp can say that?

    In asking for the study, the EPA not only settled a safety issue, they pushed back the frontiers of science, because they asked for something that had never been done and no contract lab was capable of doing.

    The Kloas Study

    Not all studies are created equal. The EPA knows that some researchers quietly do boring, methodological,comprehensive and therefore outstanding work while others are just chasing the next paycheck or media appearance. Scientists are no different than people in any job that way.

    So when trying to tackle the issue of whether or not atrazine was leading to this ‘feminization’ of male frogs, they outlined what a good study would be. Then they got all of the relevant studies available and weighted them according to those best practices.

    19 studies were included in their examination of the frog feminizing hypothesis. Two were by Professor Tyrone Hayes. Of the 19 studies, only one matched EPA criteria for their highest confidence. That was no surprise, it had been created using their parameters, they did the quality assurance, they had verified the results and the results had been replicated.

    And Syngenta even helped create that methodology. Not only does that debunk conspiracy tales about industry-funded research, it shows that industry-funded studies should help you sleep a lot better at night.

    I was able to get an introduction to Dr. Tim Pastoor, a toxicologist by training and Principal Scientist at Syngenta, because I wanted to talk about atrazine and its effects on frogs and mammals and systems biology in general. Obviously, since this was after the New Yorker article and after some increasingly bizarre allegations against Pastoor by Professor Hayes, going the normal route through a corporate communications group would have taken forever.

    I expected to reach a scientist under siege. Because of the strange claims by Hayes and the potentially unhinged behavior of a tiny segment of the environmental community that will believe anything about scientists, Pastoor now has a security detail that monitors his house.  He also had to be wondering if I was a writing a me-too article similar to the piece in The New Yorker or, if you are knowledgeable about environmental books, maybe “A Plague Of Frogs II – Starring Atrazine”, but when we finally spoke he didn’t act like a scientist under siege at all, I got frank answers and transparency about serious science issues. A writer who prides himself on asking the awkward questions of scientists found someone who didn't regard any question as awkward.

    Like most of you, I am not an expert in reproductive biology, much less in amphibians and chemicals, but I read the white paper that was the final product of the EPA analysis on the question of whether frogs were being damaged by atrazine. The EPA distilled a lot of data, much like the UN IPCC does with its climate reports. Like the IPCC product, it has to be manageable for everyone from scientists to staffers in Congress, so the EPA doesn’t underestimate the intelligence of the reader but they assume a lack of vocabulary and keep jargon to a minimum. Still, it is the length of a book and it’s about a narrow, complex field. That’s not easy going.

    But the big answer to the big question is given out early and then repeated over and over. I told Pastoor that by page 114, I finally really noticed something that upon re-reading I found I had seen numerous times starting on page 6; the EPA didn't find any problems. Atrazine is actually kind of boring scientifically. Is that why the science gets so little traction in atrazine stories? I asked.

    "I think we get distracted by claims there is a science issue with atrazine and there's just not. It's a political story, and it's a litigation story, and it's a self-aggrandizement story. But the actual science is boring because there's nothing going on," Pastoor replied.

    But, I said, I thought the EPA had a valid hypothesis about frog gonads in 2002.

    To my surprise, he agreed. Prior to that, Syngenta had created what they considered a real blue-ribbon panel of up-and-coming researchers and Dr. Tyrone Hayes, the subject of the New Yorker piece, was an early member, and when he found that laryngeal muscles in frogs were not enlarged like in a 'true' male, they were all intrigued.

    "The panel wanted to reproduce it because it was provocative," Pastoor said, but Hayes did not want to reproduce it. The results of some of the work did not make sense, and Hayes resisted the idea of doing a duplicate study or answering questions about his use of data, so Syngenta was for it when the EPA said they wanted to tackle the issue, except with more rigorous and transparent methodology. By then, Hayes had also said he found an intersex/transgender effect, at low doses of atrazine, but that had no laryngeal effect.  Things clearly did not add up.

    “The larynx is a very lobular structure,” Pastoor said, “so it’s kind of like a big, bulky piece of spaghetti. You can imagine that, depending on where you cut through that, you would get different thicknesses, and that was one of the things that the panel” (meaning the other scientists on the panel, with Hayes) “pointed out; you have to have better control. It was just good histological practice.”

    The EPA said they wanted a study to settle the matter, in a way that lacked the loose structure of private efforts – and that is a key point that critics of industry-funded studies miss.  It is easy to get published in a journal and if the journal doesn't require that you include your raw data, as most don't, it is rarely noted. A university study is not required to use rigorous methodology and most academic studies require no expertise in statistics. We have all seen plenty of published papers that were clearly fishing expeditions with lots of cut corners to make for a nice retrospective conclusion about a hypothesis we never know that anyone had in advance.

    EPA career scientists are not having that – and you can’t out-wait them either. Long after company employees and lobbyists have come and gone and EPA bureaucrats at the top have been replaced by new bureaucrats, career scientists at EPA will still be there asking for data if you ever want your product registered. An “industry-funded” study for the EPA is held to a standard that literally no paper for a journal is held, because they can make companies do it.

    The EPA wanted a study with a sufficient number of animals, a positive control, orders of magnitude dosing and clean analytical standards. And they wanted Syngenta to pay for it.

    "We had an option to do or not do that study," Pastoor said, "and you can imagine what a throw of the dice that was going to be. What if we found effects, particularly at low dose levels? One of the things I admire about this company is that, after not a whole lot of debate, we said 'yeah, we've got to do that study' even though it could result in absolutely cutting the legs off of atrazine. We needed to know and EPA was asking for it, so we did it."

    Prof. Dr. Werner Kloas is a Distinguished Professor for Endocrinology at Humboldt University of Berlin. In 2002 he had written a paper for International Review of Cytology outlining how to use amphibians in studies of endocrine disruption. He was publicly on record as being a fan of the precautionary principle and saying that a chemical should be banned if there is evidence that it is unsafe. He is so thorough his C.V. includes where he went to elementary school.  

    In sum, he was the perfect person to spearhead the study the EPA wanted.

    Neither Syngenta nor the EPA knew what would happen when two independent labs in two countries using the same methodology and 3,200 frogs set out to see what impact atrazine had on amphibian reproductive health.

    We know now. There’s no evidence of harm.


    How we are taught to think of science. Credit: Walking Dead/AMC

    That had to be something of a letdown for critics, because the science was settled. Except it wasn't a letdown at all – they just pretended it never happened.

    *****

    The Kloas study is the definitive work on atrazine and frogs. Oddly, Professor Hayes dismissed it, and the profile of Hayes in The New Yorker did not delve into its merits either. It was disqualified as industy-funded, as if the EPA is controlled by Syngenta.

    Let’s think about that: The EPA convened a Scientific Advisory Panel (SAP) in 2003. They finally concluded a lengthy re-registration of atrazine in 2006. The EPA White Paper about the frog reproduction hypothesis was produced in 2007. In 2009 they convened another Scientific Advisory Panel. Then in 2013 they opened registration review again on its normal schedule, even though the previous one was only concluded 7 years ago. Clearly the EPA is not favoring Syngenta  and if Syngenta is controlling them, they are doing a terrible job at it.

    Regardless, Professor Hayes does not think much of the EPA and the EPA does not think much of the work of Professor Hayes either. Though they looked at two of his papers, they were not considered rigorous enough to meet their standards.

    “Dr. Hayes claims not only that his laboratory has repeated the findings many times in experiments with thousands of frogs, but that other scientists have also replicated his results. EPA, however, has never seen either the results from any independent investigator published in peer-reviewed scientific journals or the raw data from Dr. Hayes' additional experiments,” EPA deputy director Anne Lindsay testified in 2005.

    In 2010, an EPA division director responded to a request from an Illinois politician who was spurred to concern by the claims of Hayes.  Donald Brady outlined how analyses of studies were done – by whole committees of interdisciplinary teams doing multiple reviews. He told Illinois State Representative Dave Winters that the EPA couldn’t use the Hayes studies because there was no data and so they could not account for sample sizes and methodology. In other words, they weren’t valid studies.

    What about other endocrinologists? While the Kloas study was a scientifically agnostic, prospective study, other labs have tried to reproduce the Hayes findings specifically. The Okazaki Institute for Integrative Bioscience couldn’t get any hermaphroditic frogs using atrazine - and they were really trying.

    Since no one can replicate the findings of Hayes, why do they continue to have such prominence in press accounts? One easy answer is that anything critical of corporations and chemicals is going to draw eyeballs to the pages of publications, and everyone from the NRDC to The New Yorker is aware of that. An editor and a journalist know a boring science story isn’t exciting anyone but if someone is willing to go on record claiming harassment and a corporate conspiracy, that will get some social media buzz.

    It's also symptomatic of something that should terrify scientists and the public – atrazine is part of an ongoing broader effort to have science done by political review, similar to genetically modified food, vaccines and climate change. 

    In 2009, Senator Barbara Boxer(D-CA) insisted that the EPA do another review in a private meeting with top-level EPA staff, right after a press release by National Resources Defense Council said atrazine in water was harmful.

    No scientists were included in the discussion.  

    This is not a new phenomenon, of course, it's been happening for as long as governments have been funding research. This "Forever War on Science" has been occurring for so long that no one even recognizes it is a war any more. Modern journalists, even some scientists and certainly the public think that's just the way it is - science is to be chosen a la carte and if you don't like the results, find someone saying something else and just choose different facts. Half of the public can comfortably be dismissed as anti-science if they disagree with anything the other half accepts.

    What about the sexual harassment, the racism and secret messages using rap lyrics I promised? What started out as a simple question drawn from a claim I saw in an interview - is atrazine harmful? - ended up being 15,000 words on the science of pesticides, kinetics, dynamics, a talk about frog sex with some of the world's foremost experts on frog sex, and the anti-science culture that effects the left and the right, and Europeans and Americans alike, so I am breaking it up into manageable chunks but by the end of it we'll all have a better grasp of chemistry, the environment and, yes, Tupac Shakur.

    Forever War On Science graphic:  A public domain picture of a fern and a guy from Castle Wolfenstein. Credit: Hank Campbell 

    Comments

    This problem bedevils American science. At its root is hate. With legitimate reason, many people hate large organizations: government regulators, business, military, law enforcement, etc. Typically the conflict is arcane, few truly comprehend the details. But bias, or selfish interests, control the public pronouncement. Profits, the corner office, or a promotion conquer truth, particularly uninteresting truth, e.g. this product harms no one. Without hate, the truth will pass in our busy lives, but hate arrests everyone's personal bias, e.g. big corporations lie again. A scandalous report can make an entire career. It may take years to unravel "what every body knows is true" but then we are off to other lies. Over time, it divides our scientifically uneducated society into dumb liberals or dumb conservatives, all with a tin hat. Mark Twain said ,"'A lie can travel half way around the world while the truth is putting on its shoes.' and that was before texting.

    The injury is that society never profits from the truth. One enormous loss it that American parents no longer encourage their bright teens to pursue careers in science and engineering, two very hard academic challenges. One anchor man, or politician can, and has, destroyed boat loads of livelihoods with "some people say....... " then interjecting their own ill informed view points, fear of technology, and hate of other Americans.

    Frank, this is stupendously well done. What a riveting article, and I find myself nearly trembling with anger at the activists who are not only scaring people to death but costing us hundreds of millions of dollars.

    As a small farmer who sometimes uses "chemicals," I appreciate that clear-eyed look at this issue (though I've never used atrazine: glyphosate and 2, 4-D are my preferred materials.

    Wakefield...Huber...Seralini...Hayes... Why are there so many jackasses in science, and, as you point out, why do their stupid--sometimes transparently stupid claims--get repeated so often?

    People love fear. People--LEFT AND RIGHT--suck on fear and dig sucking fear.

    What a waste.

    Well written piece Hank. Thanks.

    Atrazine has been in the crosshairs since I can remember. It's important to recognize something: these folks hate ALL pesticides. They deliberately pick the ones that are most widely used and go after them, because their goal is to reduce the overall pesticide "load". 2-4,D was a big target for a while. It was studied extensively like atrazine, and lo and behold! It's safe! They went after Dursban and were fairly successful. They went after diazinon and were partially successful. They're going hard after imidacloprid right now. And Glyphosate too, although that's probably hopeless. But try getting journalist to write a story that pesticides are NOT causing mass poisoning. Ain't gonna happen.

    Outstanding piece. As an aerial applicator for the last 25 years I have had a ringside seat for the controversy over pesticides and the ascendance of GMO. Triazine labels were altered during the previous registration cycle to reduce the amount of applied active ingredient permissible annually and I see now that it must have been on the basis of the original flawed Hayes study.

    The approach to pesticides taken by the environmental community borders on the hysterical and contains more than a whiff of zealotry. A piece like this is as rare as a unicorn and I salute you.

    Josh Bloom
    Brilliant
    Josh Bloom
    I find this to be a good piece. Many times, though, I find myself disagreeing out of a reflex action. I just automatically assume that if someone comes out in support of a big chemical company, they must be taking money under the table to do so.

    In reality, though, most every company tries to make the safest product they can. Even when altruism is not good enough, the threat of lawsuits is always a bit of motivation.

    Any study that can't be reproduced is a red flag. Of course, there is always the chance that the repeated studies all contain the same error, but after seven or eight, the odds of that get pretty low.

    The only phrase that keeps popping up in the studies is the one about where atrazine is safe "when used properly". Are we sure that everyone is using it properly? If not, shouldn't we be looking at "accidental overuse"?

    Hank
    I think farmers are smarter today. It is a science world, especially in agriculture. In the 1950s, that was the case, though. If DDT worked, then more must be better. And of course it was not any more effective and effectively became dangerous. Yet in proper usage, DDT still doesn't hurt anything except pests.

    In my next article I have a great graphic, though - because that was the same concern from the EPA. What if people used too much? And it turns out that, unless you strap a critter down and pump pure chemicals through a stomach tube and use surfactants, you can't ingest enough. Mammals and amphibians literally cannot drink enough in water.
    That would seem to me to be the more interesting study. One of the things that made atrazine relatively safe was the short half-life. Anything that functions as an endocrine disruptor, at a certain dose, should interfere with the hormone system in mammals.

    For an adult, the half-life is a great protection. By the time I ingest it, the amount that passes to my bloodstream is vanishingly small. For a fetus, on the other hand, vanishingly small changes in the endocrine system are what turn certain stages of development on and off.

    So when we study the effect in lab rats, for example, the only damage that would be considered a smoking gun would be birth defects. Although it is true that atrazine has been studied hundreds of times (maybe thousands), many of the high-dose studies were looking for tumor growth, or other health effects in adult mammals. The fact that atrazine does not cause tumors is reassuring, but it is not exactly the thing environmentalists were freaking out about.

    Bonny Bonobo alias Brat
    I'm busy researching 'harmful algal blooms' (HABs) for a university assignment at present and I thought I would take a break and have some light relief reading a couple of Science20 articles!

    The 'new comments' took me straight to this article about atrazine and possible feminization of male frogs and their croaks, which is a very interesting topic and a great article. It reminded me of another newspaper article that I once read about a relatively recently discovered Australian 'platypus frog' that incubated its babies in its stomach and then gave birth to them through its mouth. Less than a decade after its discovery this amazing frog suddenly went extinct along with many other frog species and the article mentioned a possible connection between Atrazine which is commonly used in Australia as a potential cause of the frog's extinction.

    Anyway I just found that 2008 Australian newspaper article by Greg Roberts here its called 'Down to the last croak - RHEOBATRACHUS silus was one of the world's truly remarkable animals' :-
    'The so-called platypus frog was one of a kind. The only species of land vertebrate animal - amphibian, reptile, mammal or bird - to rear its young inside its stomach.That makes the small black frogs as special as kangaroos or koalas. They were found nowhere but in the rainforests of two mountain ranges in southern Queensland.Zoologist and environmental consultant Glen Ingram was studying them in 1977 in the Conondale Range, in the Sunshine Coast hinterland. "There were plenty of frogs in the streams at that time," Ingram recalls now. A year later, he could find just two. In 1979, there were none, and none have been found since, anywhere, despite exhaustive searches. "Like the Tasmanian tiger, it is one of the great wildlife tragedies that this astonishing animal is extinct," Ingram says.'
    Further on in the article it says :-
    'A 2004 review by the Australian Pesticides and Veterinary Medicines Authority noted claims about the impact of atrazine on frogs but said there were "inconsistencies between studies". An updated review of the herbicide will be released soon.'
    So I decided to try and find this promised review. A quick search didn't find it and I haven't got time to look for it now but I did find this rather interesting 2012 research paper investigated the 'Interactions between atrazine and phosphorus in aquatic systems: Effects on phytoplankton and periphyton' :-
    It has been proposed that the herbicide atrazine may increase rates of parasitic trematode infection in amphibians. This effect may occur indirectly as a result of increased biomass of periphyton and augmented populations of aquatic snails, which are the trematode’s primary larval host. Evidence has also shown that nutrients alone may induce the same indirect responses. Since both atrazine and nutrients commonly enter surface waters from agricultural run-off, their spatial and temporal co-occurrence are highly probable. In light of recent wide-spread declines in amphibian populations, a better understanding of the role of atrazine in the proposed ecological mechanism is necessary. A microcosm study was conducted to quantify biomass of phytoplankton and periphyton over a range of atrazine and phosphorus concentrations (from 0 to 200 μg L−1each) using a central composite rotatable design.
    Changes in environmental conditions such as nutrient and light levels may also be induced indirectly by the contaminant itself. A 2008 mesocosm study by Rohr et al. (2008) proposed that a reported reduction of phytoplankton growth as a result of atrazine exposure (117 μg L−1) caused an increase in light and availability of nutrients, resulting in increased growth of the periphyton community in atrazine-treated mesocosms compared to controls. As snails are grazers of periphyton, populations of snails in these test systems were observed to increase under atrazine treatment, along with populations of plagiorchid trematodes, which use the snail as a primary intermediate host. Certain snail-hosted trematodes (Riberoria spp.) can cause limb deformities in adult frogs, and Echinostoma spp. which cause edema in tadpoles ( Fried et al., 1997) may also be of concern in regions of atrazine usage ( Koprivnikar et al., 2007).
    'We found significant effects of atrazine and phosphorus on dissolved oxygen, pH, and conductivity throughout the study. Additions of phosphorus mitigated the apparent inhibition of these photosynthetic indicators caused by atrazine. Despite these changes, no consistent treatment-related differences in algal biomass were observed. These results indicate that the indirect impacts of atrazine on total growth of periphyton and likely, subsequent effects on aquatic snails, are not expected to be ecologically significant at the concentrations of atrazine tested (up to 200 μg L−1) and over a range of nutrient conditions commonly occurring in agroecosystems.'

    So this study did not find any significant indirect effects of atrazine on algal biomass however my recent research into algal blooms in general has shown that there are so many variables that are not fully understood and that are involved in the production of algal blooms that one study not finding any significant effects is not in itself very conclusive. Testing these kinds of interactions in a laboratory setting would be even less conclusive because these frog and atrazine studies could easily have so many missing factors such as agricultural and nutrient run offs, snails, canopies, sunlight, salinity, temperature and PH ranges and competing cyanobacteria, fungi, and zooplankton and algae that could exist in the wild but not in a laboratory.


    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    Hank
    Indeed, if you ask any scientist - and I always do, in my 'ask the awkward questions' role - what they would look at if money were no object and they say more animals and field studies. You already touched on the problem with field studies; they are very difficult to control properly, to a point they could end up being those really lousy epidemiology studies that can correlate organic food to autism. In a field study, if you look enough, you can find anything because there are so many variables.

    So what happens instead is the EPA looks for problems and then creates a study that focuses on just what can be found. They had two special SAPs outside registration review, one before atrazine was renewed and one after, about two different things, and couldn't find anything - but they were intrigued enough to demand studies.

    Australia is being reasonable, I think, as is the US. If there is a valid hypothesis, test it. Europe is probably a little goofy - if something gets media attention, they ban it. So they banned atrazine without doing studies and thus gave Monsanto a government mandate by default over there. Now what do environmentalists complain about? The Monsanto monopoly.
    An interesting perspective on the difficulty of informing the public when scientific publications are involved. But from a European perspective, I'd like to point out the following facts:
    1) Atrazine have been banned in the many EU countries as of the 90s (Germany, Austria), and is now a Red list water pollutant due to its high migratory rate among the ecosystem and high solubility. Yet, Atrazine is still commonly found in many European freshwater and underground water bodies.
    2) Atrazine is a candidate for being an endocrine system disruptor, therefore for the precautionary principle, this chemical should at least be strictly regulated as to minimize water pollution.

    A nice 2009 review (I don't have access to scientific databases, so that's the best I could find) concluded that:
    "As in past reviews, we found little evidence that atrazine consistently causes direct mortality of freshwater vertebrates at ecologically relevant concentrations, but there is evidence that atrazine might have adverse indirect ecologic effects. However, in contrast to a previous review on atrazine (Solomon et al. 2008), we unveiled consistent effects of atrazine at ecologically relevant concentrations for many other response variables in our meta-analysis.
    [...] This suggests that atrazine should be considered an endocrine-disrupting chemical. Finally, we do not have a thorough appreciation of the reproductive repercussions of atrazine.
    [...] Although we found consistent effects of atrazine on freshwater vertebrates, the consequences of these effects remain uncertain."
    2010, Rohr, Mc Coy http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831963/

    My point being, the EPA review specifically focused on gonad development, but there are many more atrazine pollution impacts on amphibians that should be thoroughly investigated before claiming it totally safe.

    Hank
    Yes, I agree with what you say but this is why digging a little deeper is important.

    I looked at the paper you cited (in total, I looked at all 19 from the 2003-2007 SAP and about 40 overall) but it was found to have "misrepresented over 50 studies and had 122 inaccurate and 22 misleading statements". The authors did a review rather than doing any research. The EPA did not use this in its 2009-2012 SAP because of its issues, even though they paid to have it done.

    My section on endocrine disruptors did not survive editing in this piece but literally everything is implicated in being an endocrine disruptor. Studies in mammals and amphibians had so few instances that it requires cherry-picking to make it seem real. I'll give you an example - there was 1/5th of the level of endocrine disruption in frogs as there are human gay people. A researcher with an agenda could claim, therefore, that atrazine turns people gay due to it being in water samples. It would not be good science, but it would get attention.

    I don't talk about the EU here because they banned it due to its presence in water, not evidence of any harm and this was not about the political issue in pesticides (a later article will be). I don't want to bore the world with a 1,000 word comment but I played Devil's Advocate about all of these things and I talked to a number of researchers and the EPA - so I agree with your questions, the focus on them is how environmental groups avoid the science and, as I said in the article, they are much better at public relations than Syngenta is.
    What a fake article. Nothing Anti-science about it except for manipulated Tobacco science like what's generated by Monsanto and Syngenta. They will fake anything to continue their plans to dominate the world's food supply with inferior and unneeded GMO seeds. No one wants their GMO crops, they don't do the positive things that the companies claimed. Use of herbicides is up, not down. Use of pesticides is up, not down. And we the people suffer for their profits. "As if the EPA controls Syngenta," that backwards pal, Syngenta and the Big 6 control the EPA.