Merchants of Environmentalist Doubt*

Contrary to activist claims, the popular herbicide glyphosate does not cause cancer in people, says a new study.


Rene Van Den Berg/Dreamstime

A new study in the Journal of the National Cancer Institute reinforces a message that scientists have been telling us for years: Glyphosate isn't going to give you cancer. But don't expect activists to stop telling you it will.

Glyphosate, often sold as Round Up, is used to kill weeds by spraying it on crops genetically enhanced to resist it. The study, conducted by researchers at the Agricultural Health Study (AHS), followed tens of thousands of licensed pesticide applicators for about two decades. The paper found "no association" between the popular herbicide and "any solid tumors or lymphoid malignancies overall, including [non-Hodgkin lymphoma] and its subtypes." The study did find "some evidence of increased risk of acute myeloid leukemia" in the highest exposed group, but it added that this association was "not statistically significant."

This finding accords with decades of research. Again and again, scientific panels and regulatory agencies have evaluated glyphosate and concluded that its use is not associated with an increased risk of cancer in people. Nevertheless, in 2015 the International Agency for Research on Cancer (IARC) classified glyphosate as a "probable human carcinogen." This was the result of a carefully crafted anti-biotechnology campaign.

Environmental activists have perfected a highly effective scaremongering playbook, and they have been assiduously running those plays against glyphosate for nearly 20 years. First they scour the epidemiological literature to find any hint that a substance or process might cause human disease, especially cancer. This is not usually a difficult task, because somewhere, sometime, some cagey epidemiologist will have obliged them by torturing highly equivocal data into confessing the possibility of carcinogenicity. These epidemiological phantasms are then bolstered by a dodgy experiments done by activist-funded researchers.

With this chimerical evidence in hand, the activists then invoke the precautionary principle—the demand that any new technology be proved absolutely safe before people are permitted to use it, with no trade-offs allowed. Disingenuously portayed as the hoary adage "better safe than sorry," the principle actually amounts to "never do anything for the first time." As I wrote in my book The End of Doom:

"The problem is that one cannot prove a negative," notes Mercatus Center analyst Adam Thierer. "An innovator cannot prove the absence of harm, but a critic or regulator can always prove that some theoretical harm exists. Consequently, putting the burden of proof on the innovator when that burden can't be met essentially means no innovation is permissible." Just because I can't prove that no minotaurs roam the woods surrounding my cabin in Virginia, that shouldn't mean that regulators can, as a precaution, ban virgins from visiting me. (Minotaurs are notoriously fond of the flesh of virgins.)

After biotech crop varieties became commercially available in 1996, farmers across the globe rapidly began to adopt them, especially the ones resistant to glyphosate. Why? Because they no longer had to rely on plowing to control weeds, which saved substantial amounts time, fuel, and eroded topsoil. This meant reduced greenhouse gas emissions and less runoff into streams, so you might think environmentalists would have embraced biotech crops. They didn't, largely because when biotech crops were being introduced in Europe during the late 1990s, groups like Greenpeace and Friends of the Earth found they could attract funding and members by fanning fears about the new crop varieties.

Since herbicide resistance is the most popular type of genetic enhancement of crops, activists recognized that going after glyphosate would provide them with a bonanza of media attention and donations from a frightened public. And it worked. Prior to 1996, the Environmental Protection Agency had concluded that glyphosate was not a human carcinogen. A rough Nexis search using the search terms "glyphosate" and "cancer" turned up fewer than a score of newspaper, magazine or wire service articles that even mentioned glyphosate before 1996 and none that suggested that it might cause cancer. (In ironic retrospect, Procter & Gamble actually applied for patent on glyphosate to use as a chemotherapy treatment for breast cancer.) In contrast, Nexis found more than 1,000 such articles that have been published in the last three years.

The IARC panel came to its decision after being seeded with researchers beholden to anti-biotech activist organizations. Back in June, Reuters reported that Aaron Blair, the chair of the IARC glyphosate panel, "knew the unpublished [AHS] research found no evidence of a link between glyphosate and cancer" and did not report those results to his IARC colleagues. Furthermore, Blair has acknowledged in depositions that—in Reuters' words—the research "would have made it less likely that glyphosate would meet the agency's criteria for being classed as 'probably carcinogenic.'"

California regulators are now moving to require that glyphosate be listed as a carcinogen, and the European Union is struggling over whether to approve use of the herbicide.

Monsanto, a manufacturer of glyphosate, and various farm groups launched a lawsuit this week against California to stop the state from requiring cancer warnings on products containing the herbicide. Last March the European Chemical Agency concluded that "the available scientific evidence" did not warrant classifying "glyphosate for specific target organ toxicity, or as a carcinogen, as a mutagen or for reproductive toxicity." Nevertheless, the European Union deadlocked over the approval or disapproval of glyphosate last week.

If the anti-biotech scare campaign succeeds in getting glyphosate banned, farmers will be forced to use less benign and more expensive herbicides or to resume plowing, thus increasing topsoil erosion. The result will be higher food prices, more damage to the natural environment, and no improvement in public health.

*In 2010, Naomi Oreskes and Erik Conway published Merchants of Doubt, which argued that groups of industry-connected scientists "ran effective campaigns to mislead the public and deny well-established scientific knowledge over four decades." It is clear that various activist groups and a coterie of fellow-traveling researchers are now similarly engaged in misleading the public and denying well-established science in pursuit of their goals.

Disclosure: About three years ago I bought 100 shares of Monsanto with my own money for $109 per share. They were going yesterday at $117.36 per share.

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  1. “Not cancer causing”

    Has anybody studied the effects of a $15 bottle of weed killer on heart disease?

    1. Drink the whole thing down quick, and I’ll guarantee you won’t die of heart disease.

      1. How about the effects of a $15 bag of killer weed on heart disease?

        1. Where do you find $15 bag of weed?

          1. There was lots of that back in the 70’s.

          2. Where do you find bags of weed? I haven’t seen weed in anything but one of those little plastic pop top things for at least a decade.

          3. In Washington! I don’t even smoke, but some of the weekly specials at some of the weed stores here can be as cheap as $12 an 1/8! $15 is more common though. You can always score the special of the week for $100 an ounce, and sometimes as low as $80. That’s all AFTER tax. My dad smokes, so I know these things. LOL

            1. Of course the “top shelf” stuff can still be pricey. $40-50 an 1/8 is common for the best of the best still.

  2. Maybe you can’t prove a negative, but science! let’s us do all sorts of shit we thought was impossible.

  3. Ron, You going to cover or comment for Reason on the “Warning to Humanity” issued by those 15,000 scientists a few days back?

    1. “Ripple says he learned about the original 1992 warning last February and decided to update the concerns he found there with new data. “The trends,” he says, “are alarming.” Ripple says he found a decline in freshwater availability, decreases in biodiversity, and climate change, among other things.”…..anity.html

      Looks like a lot of ‘scientists’ are saying they’d like things to be better.

      1. Any group whose premise relies on “rapidly expanding population” when the global fertility rate is around 2.5 and approaching replacement should be ignored.

        1. They’re counting down our doom as the result of climate change in minutes. They need a snooze button that hits them harder.

  4. A prog’s guide to science:

    1.If it is a product made by a successful corporation that tends to donate to the GOP, or is enjoyed by icky people who don’t like green tea or yoga, it will kill you!

    2. If it is sold at Whole Foods or recommended by a nitwit celebrity or leftist blogger, it is safe.

    1. Which is why I’ll keep driving my gas-guzzling van and eating food made cheaper by pesticides by glyphosphate.

      At least until I die of cancer or the planet spontaneously combusts.

  5. My fianc? sends me junk science she reads on Facebook all the time, and this is one of those things (sort of). She was reading articles that made the claim that Round-Up caused gluten sensitivity.

    There is no bottom to the idiot barrel, as we’ve discovered.

  6. What does it matter if these crops are restricted by government or new restrictions are imposed on their use? The free market will chose which is better. Like coal.

    1. Was there a point in there somewhere?

      1. Restrictions are not a big deal. The market will sort it out

        1. OK, but restrictions ARE a big deal if they drive the cost of food upwards.
          Yes, the market will figure a way around most any gov’t distortion, but it is then a long way from what what good it can do if left alone.

        2. Put another way, it’s not a big deal if you don’t mind a bit of starvation for your fave luddism.

          1. Well someone could have said that restricting coal would have increased energy costs, but the market moved away from coal, for reasons that had nothing to do with regulation. The same would happen with a carbon tax. I’m sure.

            1. “Well someone could have said that restricting coal would have increased energy costs, but the market moved away from coal, for reasons that had nothing to do with regulation. The same would happen with a carbon tax. I’m sure.”

              Uh, we’re discussing the cost of food here.

              1. How is that any different? Clearly government regulation doesn’t matter

                1. “Clearly government regulation doesn’t matter”

                  I’m with BUCS; this has got to be a joke.

  7. The result will be higher food prices, more damage to the natural environment, and no improvement in public health.

    This is what drives me crazy about the current “environmentalist” movement. It’s all straw men and knee-jerk politicization of absolutely everything such that reducing environmental harm is not just the last thing on their minds, they actively contribute to harming the environment with their mindless partisanship.

    Just last week Jezebel was running hit pieces on Rick Perry talking about “clean coal” (as if there even is such a thing, according to Jezebel) and screeching about the unbelievable absurdity in suggesting that building fossil fuel plants in developing countries in Africa is a strategy for combating climate change.

    Of course, if they gave a shit about the issue beyond using it as a cudgel against their political enemies, they would realize that not only is there such a thing as clean coal, but that one of the areas that has seen the most impact as far as reducing global anthropogenic carbon emissions has been . . . wait for it . . . building fossil fuel plants in developing countries in Africa.

    That project, being conducted by a private non-profit, has accomplished an order of magnitude more to reduce carbon emissions than the IPCC, the Kyoto Protocol, and the Paris Accord together.

    1. The worst, to me, are the climate change worriers who oppose nuclear. There’s no bigger red flag to indicate that someone is either uninformed or has a hidden agenda. You might as well be in the anti-vaccine crowd and flat-earth club, too. Fortunately some “environmentalists” seem to be coming around to the fact that nuclear is probably the safest source of energy out there and could be the cheapest if government would let it.

      1. The worst, to me, are the climate change worriers who oppose nuclear.

        ^ This.

        “The world will end if we don’t reduce carbon emissions immediately, but we wouldn’t want to risk a disaster like a meltdown!”

        1. The death count due to civilian nuclear power plants in the west remains a distressing zero.

      2. They are Luddites. Pure and simple. They hate technology. They hat modernity. They hate humanity. They honestly wish humans would go extinct.

        “But nuclear waste has a half-life of 10,000 years!”

        You know what doesn’t have a half-life and lasts forever? The toxic chemicals and mine tailings being dumped into ecosystems in massive quantities in third world countries to make our solar panels.

        There are thriving coral reefs in the nuclear bomb craters in the Bikini Atoll. Chernobyl is a de facto wildlife preserve. Fukushima is already being taken over by nature.

        If anything, environmentalists should WANT nuclear accidents, since it scares all the humans away and the animals don’t give a shit about having a 4% higher chance of getting cancer.

      3. You might as well be in the anti-vaccine crowd and flat-earth club, too.

        Umm, they generally are in the former.

      4. I would hardly call their agenda hidden.

    2. Sadly, environmentalism was eaten whole by communists, anarchists, and madmen.

      1. Is it really consumption when it’s autophagy?

      2. What annoys me to no end that these people call themselves “environmentalists”. But how much science background do they have? Most have none, or they have taken courses in “environmental activism”. I have two degrees in ecology. I am not an “environmentalist”. I am not a luddite, I think the way forward is nuclear, and as Ron has pointed out in his book and articles, there is a lot of positive things going on in the world around us. I wish they would live in the world that they want everyone else to live in, and STFU.

  8. Disclosure: About three years ago I bought 100 shares of Monsanto with my own money for $109 per share. They were going yesterday at $117.36 per share.

    You would have killed it if you just put that same money into an S&P index fund.

    1. So, you are telling us Monsanto paid you $800 to write this story?

  9. Econazi Millerites have had to eat so many misanthropic prophesies and change the subject so many times that The End Is Nigh prophesying isn’t even in the top ten things voters worry about.

  10. From the study-
    thereby limiting analyses to participants who completed both the enrollment and follow-up questionnaires.
    North Carolina and Iowa

    1. H: Actually much better than the studies cited by the IARC, but you’re right – it’s epidemiology all the way down.

  11. It is clear that various activist groups and a coterie of fellow-traveling researchers are now similarly engaged in misleading the public and denying well-established science in pursuit of their goals.

    Is it similar when you pioneer the technique?

  12. California regulators are now moving to require that glyphosate be listed as a carcinogen,

    The party of SCIENCE, bitches!

    1. Oh yeah. Science+The Narrative=wisdom. Note that science /= wisdom, in and of itself. It’s only the science that is consistent with the pre-existing holy Narrative that’s good. Gender differences, race+IQ studies, crime statistics, anthropological studies that discredit the Noble Savage narrative and epidemiological studies that DON’T find links between “demonized substance o’ the day” and cancer…all unwelcome “bad” science.

      And remember-no matter how low the risk or how tenuous the correlation, children and the elderly are ALWAYS most ‘at risk’. Fits in every environmental story.

  13. Woops.
    were the two states used in the study
    Among 54 251 applicators, 44 932 (82.8%) used glyphosate, including 5779 incident cancer cases (79.3% of all cases).
    Here we have updated this early report, extending cancer incidence follow-up through 2012 (North Carolina)/2013 (Iowa) with 7290 incident cancer cases, and included additional exposure information from a follow-up questionnaire.

    My 2 cents.

    Are incident numbers above/below the rest of the population?
    The applicators, usually the farmers or crop dusters.
    Grain corn and soybeans are the two largest crops in both states. Neither crop is directly consumed by humans.
    So go ahead and use it to kill weeds. But if you spray it on your tomatoes, give them to Tony.

  14. 100% of the people who vote for democrats die.
    We should ban democrats.

  15. But does it matter? Lawyers are already suing Monsanto and trolling for clients on TV.

  16. So, how unbiased is the National Cancer Institute? Who is the Agricultural Health Study? Why are you quoting regulators and the EPA? No wonder there’s a credibility problem if when you take sides, you don’t address the credibility of the sources.
    Frankly, I like my Chiropractor’s answer defending the efficacy of his profession, when I asked him decades ago (when they were under attack by the Establishment): he said, “My malpractice insurance costs a fraction of what it costs an M.D.” He went on to point out that doctors are held accountable not only for their actions but for their failures to act.
    This article is useless to me and I don’t have time to go get a chemistry degree — nor search for a YouTube short-cut — in order to prove it to myself. Just tell me whether the insurance companies are charging Monsanto and their employees more for coverage than they charge other employers and employees.

    1. P.S. This article reads like the author is happy to report government and other authorities when they support his position. How did it get published in REASON? They, if anyone, should be well-aware that just because it’s called “science” doesn’t mean it’s true.
      Any product designed to kill and which actually does so merits testing by the unbiased to determine what else it kills besides herbs or bacteria (if I recall correctly how it works it kills organisms on the plant that the plant needs to live). Some bacteria are necessary to human life, too.

      1. P.P.S., Yes, I was disappointed not to have the question settled either way with credible evidence from a credible source (logic at least). So, while I’m commenting, “What about fluoride?” If it’s really that bad, maybe I can get it removed from public drinking water so the dolphins won’t be harmed when it drains into the ocean. I really don’t want to have the political process limiting my health options, and if anyone wants to add it to their own water, they can.

      2. P. syringae has been implicated as an atmospheric “biological ice nucleator”, with airborne bacteria serving as cloud condensation nuclei. Needed for rain to form at relatively high temperatures.

      3. Glyphosate inhibits an enzyme only found in plants and
        some microorganisms. The enzyme is used to make
        certain amino acids. Humans don’t have these enzymes,
        so glyphosate is very safe from a toxicology point of view.
        Apparently, it also is not really a carcinogen.

        Round-up kills any green growing plant, but with Biotech
        they are putting genes in crop plants that destroy the Round-up
        (or otherwise protect the plant from Round-up), so that only
        the weeds or unprotected plants die. It used to be only useful
        as a pre-emergent herbicide. Spray it on weeds just before
        your crop starts to grow and they will have a head start on
        the weeds. Now, it can also be used as a post-emergent,
        if your crops are now protected from glyphosate.

  17. I’m not against killing weeds, making money, technology, or science. I am against telling half of the story. Frankly, I’m not surprised the Journal of the National Cancer Institute has designated glyphosate as “not cancer-causing,” especially given chemical companies’ entanglement with government and regulatory agencies.

    – Attorneys for plaintiffs suing Monsanto found email correspondence between EPA toxicologist Marion Copley and Rowland suggesting Rowland may have colluded with Monsanto to find glyphosate non-carcinogenic.

    – Court documents also suggest Monsanto employees ghostwrote parts of two scientific reports (one in 2000 and another in 2013), which the EPA then relied on to conclude glyphosate is non-carcinogenic.

    – Court records show Rowland warned Monsanto of the IARC’s determination months before it was made public, giving the company time to plan its defense strategy.

    Email correspondence shows Rowland helped stop a glyphosate investigation by the Agency for Toxic Substances and Disease Registry (part of the U.S. Department of Health and Human Services) on Monsanto’s behalf ? a task Rowland allegedly said he should “deserve a medal for,” were he to pull it off (which he did).

    Correspondence also suggests Monsanto was planning to rely on Rowland’s influence after his departure from the EPA. In an email to a colleague, Dan Jenkins, Monsanto’s regulatory affairs manager, noted Rowland “could be useful as we move forward with ongoing glyphosate defense.”

  18. Modern environmentalists basically bitch about minutiae because most of the major environmental problems we had in the 20th century got solved. So basically they have to keep fighting something to keep the gravy train rolling. Hence climate change, bitching about logging in the USA even though we have more forest land than in 1900, etc etc etc.

    THAT SAID, the dirty hippies sometimes have half a grain of truth in some of their arguments, they just usually blow it all way out of proportion. They’re even fully right sometimes, like with BPA fucking with our hormonal systems to a degree. Although I don’t think government intervention is typically called for with most stuff, I do research some of the dirty hippie bitching points and find enough reason to be minorly concerned that I change my personal behavior.

    I don’t think any ONE chemical out of the bajillions they whine about matters… But I do think the constant exposure modern people have to a wide array is probably not good for us. Likely won’t kill you right off, but in a death of 1000 cuts kind of way it’s probably not helping either. So I try to limit chemical exposure when I can, which sometimes includes buying certain things organic. Certain crops are especially doused, whereas others aren’t. Strawberries are practically soaked in chemicals, bananas not so much.

  19. Thinking things through critically is the thing that matters. You shouldn’t blindly accept all modern developments are harmless, many have proved to be bad after a time… But you also shouldn’t assume ALL new things are bad either, as many aren’t.

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