Pesticides and food: It’s not a black and white issue

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Glyphosate is no bee killer

Honey bees have had a rough decade or so. Starting in 2006, Colony Collapse Disorder (CCD) started to empty hives of these precious pollinators. While CCD appeared to have ebbed by 2012, honey bee losses, mostly linked to different factors, remained high enough to be of concern to the U.S. Environmental Protection Agency and the U.S. Department of Agriculture. And earlier this summer the White House announced that Interagency Pollinator Health Task Force would begin digging into the problem further.

As far as what caused CCD, nobody knows, although most scientists are convinced it was not neonicotinoids, as many advocacy groups have claimed. It’s not the first time managed honey bee hives have been decimated by unexplained factors. Indeed, most experts agree that the cause was likely multifactoral, citing a combination of stressors that include pests and pathogens, disease, nutrition, genetics, environmental exposures and commercial bee hive management practices.

CCD appears to have passed (for now), and populations of commercial honeybees have recovered. But those facts haven’t stopped anti-pesticide and anti-GMO activists from blaming, and continuing to blame, a number of pesticides, from neonics to glyphosate (the active ingredient of Roundup).

  • In a 2013 paper, anti-GMO scientist Don Huber took a glancing swipe at neonicotinoids for possibly causing CCD, but warned his readers to focus on “a more problematic cause of CCD”:  glyphosate. Huber claimed that glyphosate’s widespread use worldwide could only link it to bee mortality. In other words, correlation equals cause.
  • Quack website Natural News ran a headline in 2014, “Groundbreaking study shows that Roundup causes honeybees to starve,” based on an Argentine study that did not actually show that. But the story has continued to thread its way through anti-GMO websites.
  • As for the study itself, the researchers used laboratory-raised bees and fed them the glyphosate active ingredient in a sucrose solution. They found that “field realistic doses” of glyphosate did not actually starve or kill the bees, but instead affected their learning and nectar-homing behavior. The researchers warned that “However, no effect on foraging-related behaviour was found.” Critics noted that the doses were not field realistic and bees do not regularly sip on glyphosate cocktails.

Glyphosate scares un-field-realistic

This September, the USDA’s Agricultural Research Service published a study looking at “field realistic doses” of 42 pesticides (40 insecticides and miticides, one fungicide, and one herbicide — glyphosate) on honeybees. In their study they used honeybees from local (Arkansas) beekeepers, and set up spray conditions designed to better replicate “field realistic” exposures. Importantly, they not only measured lethal concentrations and doses, they also matched those lethal concentrations to actual commercial uses of each pesticide.

Of the 42 pesticides tested, 26 of them killed more than 99 percent of the field test bees. These included common organophosphates, neonicotinoids, carbamates and pyrethroids. But not all neonicotinoids killed the bees, and one pesticide came in dead last on the deadly list: glyphosate. Glyphosate’s lethal concentration was already quite high, which is a good thing (requiring 4.62 x 10 to the 34th mg/liter versus the worst, the neonic dicrotophos, with a toxicity of 24.92 mg/liter). In other words, it takes tons of glyphosate to kill a bee!

Related article:  Sri Lankan tea industry faces devastating crop losses following glyphosate ban

Even when factoring in the widespread use of glyphosate — a favorite factoid used by anti-GMO activists to point to glyphosate harm — the herbicide still came in dead last in the study. This is consistent with earlier studies that on glyphosate that were presented to the USDA and EPA in support of the Roundup approval.

The USDA team conducted the study to show that alternatives existed for farmers to eradicate persistent pests like stink bugs and the tarnished plant bug, which persist in row crops like cotton, soybean, rice, and corn. Seven pesticides, including the neonic insecticide acetamiprid, did not appear to kill more than 1 percent of bees that were exposed. Other members of the least-toxic list also included new pesticides with unique ways of killing harmful insects.

Over the past 20 years or so, adoption of transgenic cotton, soybean, rice, and corn has become widespread. This change has reduced the threats from chewing insects but hasn’t had much of an effect on sucking bugs like stinkbugs and the tarnished plant bug, which moved in to the space vacated by the chewing insects. Thus, in some cases farmers have had to use additional pest control methods such as seed treatment insecticides and leaf sprays. Seed treatments are applied before the seed before planting and provide protection to the developing seedling; used correctly, they minimize the likelihood that any non-target or beneficial insect will ever come into contact with the insecticide. Leaf sprays are applied to the growing crop and should be applied in a way that minimizes exposure to non-target organisms; however,there is a greater chance that pollinating insects might come in contact with the pesticide. It’s therefore important to use the best product for the pest in question and to not demonize an entire class of pesticide based on perception and misinformation.

While no farmer has ever jumped at the chance to spray pesticides, the study calls into question existing (in the European Union and parts of Canada) and proposed (in the US) harsh regulations, on neonics. For farmers, there are actually options. And at least two of them involve apparently safe pesticides that the anti-GMO and anti-pesticide movements want to ban.

Andrew Porterfield is a writer, editor and communications consultant for academic institutions, companies and non-profits in the life sciences. He is based in Camarillo, California. Follow @AMPorterfield on Twitter.

50 thoughts on “Glyphosate is no bee killer”

  1. “Glyphosate’s lethal concentration was already quite high, which is a good thing (requiring 4.62 x 10 to the 34th mg/liter…)”

    The entire earth checks in at 5×10^30 mg. I’m doubtful that it takes 10,000 earths worth of glyphosate in 1 liter of water to kill a bee. But that’s just the skeptic in me.

    Or is this some kind of anti-homeopathy?

    • Interestingly, that astronomical (or at least inter-planetary) number appears in the actual linked article. Which suggests that someone involved in that research doesn’t actually know or care what those numbers mean. This is the sort of thing I used to see back in my TA’ing days – students would make a mistake with their calculators when solving an exam problem and write down whatever nonsense the screen showed without thinking about it.

    • This was extrapolated by the USDA researchers from data that showed virtually no increase is glyphosate toxicity to bees with increasing dose. You have to follow the graph out an awful long ways before you approach 50% lethality of bees. Definitely, statistics gone wild. By the way, the entire liter of water weighs only 1000 g. The same researchers calculated the LD50 of glyphosate at 35 quintillion metric tons per bee, more that a good-sized continent. (Does that kills 50% of the bees exposed; half of them should survive.)

  2. “it takes tons of glyphosate to kill a bee!” Well, there you go. You saddle a bee with a sub lethal singular ton of glyphosate and the poor thing can’t even get off the ground. So, naturally, that affects its navigation ! :)

      • And what tests for chronic toxicity are you recommending, Tinkler? Oh, I see, you don’t know what you would be testing for or how you would test for it. More fraudulent emissions from you. Got it.

        • Wouldn’t it be nice if he would actually talk to professional beekeepers? Ah, now I remember …the “right to know” doesn’t apply to him. He has a perpetual “right to speculate wildly.”

          • Those poor innocent professional beekeepers wouldn’t thank you for putting the Daft Tinkler on them. Can’t speak for the hobbyist beekeepers but the few professional beekeepers I’m acquainted with do not suffer fools. They would probably drown him.

  3. A ton of glyphospate? I figure you could drown the little cuss with way less than a thousandth that much but I’m blamed of being too stingy with my crop inputs all the time so what do I know? I figure I could drown an anti-gmo activist with only about a quart or two if someone would hold ’em down for me.

  4. In 2007 scientists at Penn State also reported publicly that two of the most detrimental pesticides found in bee products were miticides applied by beekeepers. I was at the Entomological Society of America meeting where they reported it. You read that right. Within a year of the beekeepers’ beginning their vilification of neonicotinoids, it was being inferred that the beekeepers’ own practices were putting serious stress on hive health. They don’t tell you THAT. Nor do they tell you that the working groups investigating CCD at its outbreak were also implicating the importation of illegal foreign bee product into the States–which may have been responsible for Israeli Acute Paralysis Virus (IAPV) introduction to the domestic bee population. This is a virus that has been associated with numerous stressors leading to CCD. So much for the sanctimonious, high-and-mighty beekeepers.

  5. Glyphosate doesn’t kill bees. That’s pretty obvious. My beef with glyphosate (and I understand how really useful it is) is its impact on available bee forage. If you talk to older beekeepers, they’ll tell you that you used to be able to make honey off the weeds surrounding and in between the rows of corn in a corn field. The corn still did reasonably well as it was so much taller than the weeds. But the weeds could still flower under the canopy of the corn and the bees found the weeds. Now, corn fields are complete deserts with respect to weeds. Land use has always and will continue to impact bee nutrition. Weedless grass is completely useless, so the more of that we have, the tougher we’re making it for pollinators. So glyphosate, while a great success, just removes a lot of wild forage, and I wish we’d get some of those weeds back.

    • I guess that’s an indication of how it’s not just about the tool, but what you do with it. I was under the impression that farming “good practice” now frequently emphasised leaving unmown, untreated borders on fields to protect biodiversity. That should be possible with any herbicide (so is not really a glyphosate issue at all), but requires an active choice to preserve those borders — and hence sacrifice some growing space.

    • Gritnix you have been cruelly scammed by those sainted “old beekeepers” who have filled you with ridiculous tall tales. I have some experience with those sorts of characters (a few have been neighbors) and when I am pressured to attempt political correctness I charitably write off their colorful prevarications as wildly eccentric and mischievously misguided.

      I also have more than a little experience in and around the corn fields you blindly reminisce about and, for the life of me, I do not recall any time or place anyone has permitted wild flowers among the corn rows sufficient to support any respectable colony of honey bees. Any farmer, before glyphosphate or since, who would make a habit of being so slothful would be out of business before long because, you see, under severe weed stress corn does NOT do “reasonably well” — it struggles and punishes the lazy farmer by reducing yield significantly, not to mention the insufferable difficulty of tilling weed choked fields in preparation for the the next crop. A farmer who does so just once will not willingly repeat the experiment, nor will he suffer his proteges to be so wasteful.

      You would do well to reserve your asinine proclamations about how farming historically has been conducted, and how in the future it should be, for those audiences who are at least as ignorant as yourself. Out here in the real world you discredit not only yourself, but all of your fellow anti-GMO, anti-agriculture, weed-worshiping activist fanatics. Your preposterous “beef with glyphosphate” is a profound embarrassment – and with that I’m being gentler with you and more politically correct than probably I should be…

      • Yep, and before that we cultivated weeds out of crops manually. We never let weeds get the upper hand if we could help it.

        Besides, common weeds we battle in our cropping are not significant sources of nectar for honey bees. In fact, after the various trees, many of our cultivated crops such as clover, canola, alfalfa, soybeans, trefoil, etc actually are important sources.

        • Wow. I really got slammed here. Ok. No worries. I won’t ever speak up here again. Clearly no one wants to hear anything dissenting (forgot this wasn’t a skeptics area). But just a few things about me.

          I think transgenic technology is great. Love it. GMOs are delicious. I also understand everything is made of chemicals. The word chemical tells me nothing. The word natural tells me nothing. Correlation does not mean causation, and the dose makes the poison.

          Also, I’ll go with you on that Farmer….many large weeds are not significant sources of nectar. But at the same time, no one in my neck of the woods (a large ag area) grows those things. I’m not in a canola area nor clover nor trefoil. Alfalfa here is cut to make hay before it blooms, so nothing off that. As I understand it, soybeans are hit or miss. A few varieties make nectar, others make none. I’ve never made honey off soybeans (I have 15 hives at present) here even though they’re grown extensively, but I know it is possible depending on the variety planted.

          My only points are these. Bee nutrition is important. Weeds can offer variety and nectar/pollen sources during times of the summer that almost nothing else is blooming (we have a dearth here in July-August). Glyphosate (yes, and plenty of others) kills a lot of weeds. And no it’s not glyphosate’s “fault”. We kill weeds in lots of other ways. So it’s all impacting nutrition. Is it the “main” issue facing bees? Of course not. Varroa mites are still the biggest threat and biggest indicator of a hive’s survivability, and the beekeeper has to manage that. But if we could get past killing every weed around, it’d make it a little easier on the pollinators. Certainly wouldn’t fix it all, no way, but it’d help.

          • Sort of had you figured for a beekeeper, Gritnix. And yeah, you got slammed – but gently, believe it or not.

            I will apprise you of one relatively new (last 10 years, or so) trend in agricultural America that you ought to be aware of — advances in soil conservation and water quality continue to be made and to that effect more and more buffer strips are being set aside. Along streams, along livestock housing, along wetlands, along just about everything in sight. These, by design are left untouched to grow into tangles of brush lots and such. In the meantime they are magnificent reservoirs of weeds and wild flowers. Your bees are offered more and more of a smorgasbord all the time without letting our crops grow to weeds and ruin.

            Have you and your beekeeper buddies ever considered lobbying to pay for planting these buffer zones to bee feed? You know, go after something constructive that you all actually have some expertise in? You’ll piss off fewer farmers that way. I should think you of all people would recognize you will attract more bees with honey than with vinegar.

          • I actually don’t piss off any farmers (unless they’re here apparently), some of my bees are on farms actually. And I totally get it. If I was paying my electric bill and my mortgage and clothing my kids with corn or soybeans, I’d use the most advantageous tools I had at my disposal. So I totally get it. I just wish it was different. Wishful thinking, not a “ban it all” attitude. Farmers feed us all, we need them, and they need their tools.

            Local beekeepers here have talked quite a bit about that kind of thing, but unfortunately where I’m at we just can’t compete. Land around me is so valuable it’s either tilled or built. Good tillable acreage around me goes for $20K/acre, so a 50 acre farm and you’re looking at a million. Turn that into homes and the price per acre goes up 4-5 fold once divided. It’d be nearly impossible for us to pay enough to any farmer not to till even one bit of that land, and I wouldn’t blame him at all.

            And in that is the local nature of beekeeping I guess. And that’s what probably leads to my comments and maybe your disagreement with them…that in my area, and not necessarily most, land is so valuable that those areas of weeds and wild growth are few and far between. Directly beside farm buildings here is mowed grass. People are infatuated with their grass here while most farmers keep extremely neat looking farms. Yes, it does look very nice and well kept, but very few weeds.

            More than 20 years ago my aunt and uncle came to visit and said every bit of land was one of 4 things….a church, a cemetery, a house, or a (planted) field. Since then the farms have been reduced to be replaced with homes in subdivisions that plant useless grass, but that’s still the state of things. I’m just in an area that is really that way.

          • Sounds like you should have been excoriating suburbia instead of corn fields in the first place. All this false blaming and rancor to finally get the truth out. Tsk, tsk.

          • Not totally. I’m lamenting the loss of pollinator nutritional sources. Suburbia surely contributes to that. But so does the use of herbicides, selective or not, farm or not. The article focused on agricultural glyphosate use, hence my comments within that context. Would I rather have weeds than food? Of course not.

    • Well, jeez, my anti-GMO talking point says, “Complain loudly about Superweeds that have become immune to Glyphosate,” and here you go and complain that Glyphosate is still so effective that NO weeds can survive anymore. Can’t we coordinate our whines a little bit better???

    • Bee forage can be planted thoughtfully in many places. Many farmers are already preserving the edges of their fields, ditches, and other locations (not IN their crops). Open space and buffers can be used to plant bee forage also. Presuming that bee forage is a lost cause unless it’s planted right in the middle of a crop doesn’t take into account the many other growing opportunities there are for assisting pollinators.

    • Glyphosate is a selective microbicide of great potency. Even 10 uM concentration can severely inhibit some microbes — but not all. Some are immune to it, like the Agrobacterium from which the alternative EPSPS gene was taken and spliced to make the Roundup Ready crops. So glyphosate exposure over time can affect the gut microbiota of creatures including bees, and disrupted gut microbiota can affect survival outcomes and general health and immunity.

      • Back to broadcasting your cockamamie causation lies again, eh Tinkler, you ridiculous fraud?

        Where is your data, Tinker?

        Where are your replicating studies, Tinkler?

        Where is your body of literature, Tinkler?

        Where is your credibility, Tinkler?

        A ridiculous fraud, just ridiculous.

    • Your cited source confirms the very low toxicity of glyphosphate. Scientists sprayed bees directly with the stuff and “killed practically no bees in the tests.”

      Really who pays you to try to scam us with THIS???!!!

      Go back to smoking your hives and stop blowing your smoke up our skirts.

    • The big thing is that this tested ACUTE toxicity but the real effect would be the longer term exposure, like a couple of weeks, and the effects on gut microbiota that accumulate over that span, and even multi-generationally. This would weaken the immunity and overall health of the bees. The industry chooses to overlook this on purpose.

      • You have no reseach to back up your bizarre claims of chronic toxicity and weakened immunity. You have nothing! The result could just as easily be an enhanced immune response for all you know, Tinkler. You are such an egregious fraud it is nauseating. Are you so addicted to self-humiliation you can’t resist exposing your ignorance on this site? You are one sorry POS, Tinkler.

  6. I could give you more studies undertaken at frankfurt university the university of sussex, and at least sixteen other incidences of the effect of sub lethal doses of glysophate to name one of many. Its quite simple peaple we can ignore it or address it, the consequence of ignoring it is huge. Yes I am a beekeeper yes I am concerned, yes I am convonced after visting a farm on which bees had been present for thirty years with no issues then all of a sudden the population collapsed, now luckily enough the farmer loves his bees, and was really upsett when he found out that the round up he had used to spray oxalis had nealry wiped out the colony he sprayed around the hive.

    • Effects on the gut microbiota over weeks or months, caused because glyphosate is a selective microbicide and kills some species within the gut microbiota, thereby disrupting the natural balance that has evolved and supports the bees’ health. I am also a beekeeper. I have experience colony collapse probably due to nearby fungicide spraying. See this article on a related topic, another pesticide that disrupts the gut microbiota:

      • Oh, what a blatant fraud you are Daft Tinkler — you’ve fraudulently claimed to be a scientist, a farmer, a carpenter and now a beekeeper! Ha, you are none of those things. Just full of beans right up to your ears. Do you really think you can con sensible people into believing your silly nonsense? Where is your data, Tinkler? Where is your body of literature in support of your cockamamie claims? All non-existent, just like your various personas, you ridiculous fraud.

        • I am beginning to think he is mentally ill …. All these truly bizarre claims about his multiple backgrounds. Multiple personality disorder, maybe? He’s also probably a licensed psychotherapist who will disagree with my assessment, but I’m stickin’ to it.

          • Anyone who would name himself “Sage Thinker” has a few screws loose, at the very least. Especially an arrogant ass with as little sense of humor as he displays. He certainly does thrive on self-humiliation. Never seen anything quite like it, really.

  7. Something’s screwy with the math. 4.62 x 10 to the 34th mg/liter? With a density of 1.7 g/cm3, 4.62 x 10 to the 34th mg would occupy a volume of about 2 x 10 to the 28th liters. That’s like 20000 moles of liters! That’s more than 10 million times the entire volume of water on earth. Obviously, you can’t fit that many liters of solute into one liter of solution. The theoretical maximum concentration would be 1.7 x 10 to the 6th mg/L. I don’t doubt the relative bee-compatibility of glyphosate, but you either have a numbers or units problem here.

  8. Treating this site like anything other than shill-fest for Monsanto would be a BIG mistake. Because that’s what it has always been, is what it will always be. Zero non-funded science here unless it backs up an agenda, agenda first at all times.

  9. first officer you appear not to know what you are talking about , our gardener sprayed glysophate around one of my hives , a strong one , without my knowledge ,just less than two and a half months ago , it is now dead all but a few hardy individuals clinging on in between two frames, I suspect that it is because of the evaporation vapour of the chemical sitting around the hive in a cloud that has allowed it to do as much damage as it has , it was the only one in the yard proper and was so strong I had intended to breed from it , nothing else has been near it except me checking it occasionally

  10. A swarm that became tired? I don’t think so, bees and other types of swarming insects have superior instinctual radar better than any man-made device on earth. The bees know exactly where they are going and have been navigating their destinations thousands of years before man even existed. I know as well as anyone else who can use 10% of their brain this is a direct result of the Monsanto pesticide known as “Roundup” or the chemical name “glyphosate”. Glyphosate is a deadly toxin to any organic or in-organic cell known to man. Glyphosate has been found in honey and many man made foods and has been proven to kill and to starve honey bees. The State of Florida, of all states should have a glyphosate ban in place, but we are too complacent and our elected politicians are all paid off.

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