A Fog of Death: The Hubris of Pesticides

Silent Spring - Rachel Carson.pngWe have learned a lot since 1962, when Rachel Carson’s book, Silent Spring, documented how the pesticide DDT was responsible for reproductive disorders in birds and cancer in humans. That book is often credited with launching the modern environmental movement, and in that movement pesticides have held a very high place among the deadly follies that humans have unleashed on the world.

Sometime soon we hope to post a new piece by Varda Burstyn on chemical pesticides on this page, and we’ll look at the various ways in which these products have set out to kill “pests” but are blowing back on us and the creatures that sustain us. Recognition of this fact has lead to a spreading movement to ban pesticides in cities, especially – but not only – for cosmetic uses. In Canada, over 170 cities have banished these products; in France, 900 municipalities. The U.S. has been too slow to take this up, but very recently, Portland, Maine’s city council joined this movement, and California’s top court issued orders to halt massive spraying of three different types of pesticides by the state. We’ll be writing more about that too.

But in the meantime, below we offer three articles you may not have already seen. The first two are on the dangers of one the most widely-used pesticide on planet Earth, Monsanto’s Roundup, picked up from the wonderful website of Eco-Watch, where daily and weekly you can find compilations of some of the most important environmental stories, particularly those linked to food and agriculture. The third article is about the hot-seat pesticides called neonicotinoids and their deadly effects on bees, from Scientific American, which needs no introduction. And, in the sidebar, we also offer important material from the website of the team headed by Gilles-Eric Séralini, professor at the University of Caen. It’s all about why he’s the man who has most often been in Monsanto’s cross-hairs since 2012. You won’t want to miss that.

Monsanto’s Roundup Destroys Healthy Microbes in Humans and in Soils

By Julie Wilson

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Graphic Credit: EcoWatch

We’re only beginning to learn the importance of healthy gut bacteria to our overall health—and the relationship between healthy soil and the human microbiome.

We know that the human microbiome, often referred to as our “second brain,” plays a key role in our health, from helping us digest the food we eat, to boosting our brain function and regulating our immune systems.

Similar to animals, plants and soil, our bodies contain trillions of microbes—microscopic living organisms, such as bacteria, fungi and protozoa. The microbes in each person’s body are unique, but not random. They colonize in the body, beginning from birth, depending on the microbes passed on by the mother. Over our lifetimes, they evolve according to our unique exposure to the outside world in order to protect us from disease such as cancer, diabetes and even autism.

What happens when our microbial community is disturbed? New research suggests that exposure to environmental toxins, such as pesticides, may alter the human microbiome, leaving us more vulnerable to sickness and disease.

A second new study suggests that the most widely used herbicide on the planet—Monsanto’s Roundup weedkiller—could be causing more damage to our gut microbiome and overall health than we thought. Not only does the weedkiller contain glyphosate, but in its complete formulation, it also contains toxic levels of heavy metals, including arsenic.

Glyphosate and Its Unintended Effects

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“Microbes will feed the world…”                                                Graphic Credit: Modern Farmer

A new study shows that Monsanto’s Roundup weedkiller, which we already know damages healthy soil microbial activity, also damages the gut microbiome of rats.

The study, published by Prof. Gilles-Eric Séralini at the University of Caen, France, raises new alarms about glyphosate, the most widely used herbicide in the world despite mountains of research pointing to the weedkillers damaging impacts on human and environmental health.

Glyphosate, the key active ingredient in Roundup, is destructive to the environment. A recent article by GM Watch details the editor of No-Till Farmer, a magazine that advocates for the use GM crops and glyphosate herbicides in no-till systems, is changing his thinking.

John Dobberstein, No-Till Farmer’s senior editor, recently wrote that “there may be trouble on the horizon for glyphosate,” citing research showing that glyphosate lingers in the soil—and in high amounts—long after it has been applied.


Graphic Credit: GEN

Citing other researches, including Robert Kremer, a retired research microbiologist with the USDA-Agricultural Research Service and adjunct professor at the University of Missouri, Dobberstein wrote that glyphosate quietly lingers in soil years after it’s been sprayed, damaging non-target crops and suppressing beneficial mycorrhizal fungi, which help plants obtain nutrients from the soil while offering protection against disease.

The herbicide also harms beneficial soil organisms such as small insects and earthworms, while leaving behind chemical residues that wind up in our waterways, Dobberstein wrote, as reported by GM Watch.

Microbes Prove Their Value in Humans

While some microbes cause disease, the majority of these cells assist us with everyday processes, such as digesting food and keeping harmful bacteria at bay.

According to an article published this month by, 70 to 80 percent of your immune function resides within your gastrointestinal tract or “gut.” Poor gut health is associated with autism, behavioral disorders, diabetes, gene expression and obesity.

If, as this recent article in the Atlantic claims, “The microbial community in the ground is as important as the one in our guts,” then the new Séralini study doesn’t bode well for us humans—especially if we keep dousing the world’s soils with glyphosate, and consuming glyphosate-contaminated foods.

Arsenic and Old Monsanto

ArsenicAs if there aren’t enough reasons to be worried about glyphosate, one more reason emerged last week when scientists reported that glyphosate-based herbicides, including Roundup, contain toxic levels of heavy metals, including arsenic.

Photo Credit: WakeUp World

Glyphosate, the active ingredient in Roundup has been the subject of intense scrutiny and controversy. Documents recently made public as a result of multiple lawsuits filed against Monsanto by people who blame exposure to Roundup for their non-Hodgkin lymphoma suggest Monsanto has known for decades about the health risks related to glyphosate.

Some countries have banned its use.

But as the authors of this latest study point out, glyphosate is not the only ingredient in herbicides like Roundup—it’s one of multiple ingredients. Those other ingredients make glyphosate-based herbicides even more dangerous than we thought—and should lead to a global ban on all glyphosate-based herbicides.

According to Prof. Gilles-Eric Séralini, one of the authors of the study:

These results show that the declarations of glyphosate as the active principle for toxicity are scientifically wrong, and that the toxicity assessment is also erroneous: glyphosate is tested alone for long-term health effects at regulatory level but the formulants—which are composed of toxic petroleum residues and arsenic—are not tested over the long term. We call for the immediate transparent and public release of the formulations and above all of any health tests conducted on them. The acceptable levels of glyphosate residues in food and drinks should be divided immediately by a factor of at least 1,000 because of these hidden poisons. Glyphosate-based herbicides should be banned.

Will the U.S. Environmental Protection Agency agree? And follow the lead of countries like France and Germany that have proposed countrywide bans on glyphosate?

We can only hope.

Honey Bees Attracted to Glyphosate and a Common Fungicide

By Dan Nosowitz

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                                                                                                                        Credit: Modern Farmer

All species evolve over time to have distinct preferences for survival. But with rapidly changing synthetic chemicals, sometimes animals don’t have a chance to develop a beneficial aversion to something harmful.

New research from the University of Illinois indicates that honey beeswhich are dying en masse—may actually prefer the taste of flowers laced with pesticides that are likely harmful. The study tested honey bee consumption of different sugar syrups, some plain and some with different concentrations of common pesticides. They found that while the bees didn’t care for syrup with extremely high concentrations of pesticides, at low levels, the bees flocked to those pesticides.

Among the pesticides tested were the ever-controversial glyphosate, the most common pesticide in the U.S., which previous studies have also shown to be attractive to honey bees. Chlorothalonil, which is ranked as the 10th most commonly used fungicide in the U.S., usually on peanuts and potatoes, also proved to attract more honey bees. (The connection between fungicides and honey bee health is not that clear; studies suggest they are not in themselves highly toxic, but in combination with other factors can be dangerous).

The bees did not universally prefer adulterated syrups; the researchers note that they avoided prochloraz, a fungicide sold under the name Sportak. And of course, laced sugar syrup is not the same as a flower in the wild. Still, it’s another alarming bit of news about our bees.

Reposted with permission from our media associate Modern Farmer.

Widely Used Pesticide Is a Buzzkill for Honeybees

Findings add fuel to the debate over whether a commonly used chemical damages insect populations

By Leslie Nemo on June 30, 2017

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Credit: Adegsm Getty Images/Scientific American

Honeybee stings ache for a good reason: This species knows how to brawl. But as it turns out, these black-and-yellow pollinators are quite vulnerable themselves—especially to neonicotinoids, a pesticide commonly used to ward off crop-munching pests. Two new studies, published this week in Science, address this question by studying large populations of bees in multiple locations for months on end. The results add substantial weight to the claim that neonicotinoids damage bee populations.

“I hope that my study kind of makes the debate go away,” says Amro Zayed, an entomologist who studies social insects at York University in Toronto and is co-author of one of the new reports. Even though honeybees are not the intended targets of neonicotinoids, any indication that the resilient insect is suffering from the chemical means less-adaptable species might be in trouble, too. The pesticide is intended to eradicate insects that chew up or suck on grain crops—which is why these substances coat almost all corn and 50 percent of soy seeds in the U.S. “It’s difficult, if not impossible, to find corn not treated with neonicotinoids,” says Shiela Colla, an ecologist also at York who is unaffiliated with the study research.

Most prior research on the bee–pesticide relationship has only involved feeding the chemicals to small populations in lab settings or observing a few populations in nature for a couple of weeks. Such stand-alone studies do not gather enough evidence on the true nature of honeybee behavior, Zayed says. Colla agrees, which is why she praises the York study’s sample size and length.

In their experiments Zayed and his colleagues divided 55 bee colonies among five apiaries close to cornfields and six so far away that inhabitants foraged nowhere near the crops. From early May through September 2014 the researchers only interfered to collect pollen and nectar samples from the hives every few weeks.

neonicotinoids-bachmans-20142Chemical analysis of the samples revealed neonicotinoids were the most threatening compound among all pesticides found in the nectar samples. One neonicotinoid in particular, clothianidin, was the most abundant. As for how it ended up in the samples, the researchers calculated that less than 2 percent of all neonicotinoids found in the hives were from corn and soybeans. The vast majority was from what Zayed calls “bee-friendly” flowers—like goldenrod, willow and clover—that often grow on the perimeters of crop fields. In fact, bees were picking up clothianidin-laced pollen from neighboring plants well before and well after seeds were planted, meaning the chemical pervades and contaminates surrounding areas for much longer than the planting season. Graphic Credit:

The second study, led by several institutions in Germany, Hungary and the U.K., also raised bees in agricultural environments tainted with pesticides. “It’s actually what farmers are doing normally, and that’s why it’s important,” Richard Shore of the Center for Ecology & Hydrology in England said at a press briefing. They left 33 colonies in test areas that exposed the colonies either to neonicotinoid-treated rapeseed plants or crops untreated with pesticides. The teams assessed bee population survival twice—once when the crops were flowering and again after winter. Clothianidin also struck these bees hard. Over the winter 25 percent of the Hungarian bees and almost all the British bees died. Neonicotinoids also put a dent in those bee populations during the crops’ flowering period. The German bees, on the other hand, not only emerged from the winter unscathed but their population numbers increased in spite of neonicotinoids during rapeseed plants’ flowering season. Although the researchers are not sure why the German bees did so well, they noted this population also consumed less than a third as much rapeseed pollen as their those in the other countries.

The European study stopped at field experiments but Zayed and his team took things a step further. The group fed select bees pollen laced with clothianidin at levels similar to those found in their natural environment and stuck tracking devices on the contaminated bugs’ backs. “We didn’t have to make guesses” about the chemicals involved, Zayed says. “We essentially observed what real colonies in corn were getting exposed to and mirrored that in our experiments.”

This lack of guesswork paid off with precise results. Insects that ate contaminated pollen had a 23 percent shorter life span than their untreated counterparts. They also took up to 45 minutes longer on their forage journeys, suggesting the bees struggled to remember where home was. Treated bees were also worse at identifying and removing diseased individuals from the hive—a task required for maintaining overall hive health. The net effect, Zayed explains, is a slow decline in populations over weeks.

Much of what Zayed and his team observed has been documented by other researchers. Christian Krupke is one of them. An entomologist at Purdue University, Krupke published studies on the appearance of neonicotinoids in crop-adjacent plants last year.* As evidence mounts, Krupke says, the next question is, What can we do? “The current answer,” he says, “is we can’t do much.”


Photo Credit: Illuman Apiary

The European Union banned the use of neonicotinoids on certain plants in 2013; the U.S. Environmental Protection Agency has just launched an investigation into the compounds’ harmfulness, the results of which will not appear until 2018. Maryland was the first U.S. state to announce a ban on the chemicals, and it will take effect next year—although farmers are exempted. Farmers may not need the pesticide as badly as they might think, however. John Tooker, an entomologist at The Pennsylvania State University who has published research with his graduate student on the pervasiveness of neonicotinoids in U.S. agriculture, estimates only 10 percent of fields need the chemicals. “We’ve scouted untreated fields for the pests” they aim to defend against, he says, “and we have difficulty finding them.”

Yet Zayed admits honeybees are not the best species for studying the effects of pesticides on insects in general. “The honeybee colony is a marvel of natural selection,” he says, one that often ramps up hive activity in response to an environmental stressor. Krupke agrees, saying this innate adaptability might explain why the European study showed German bee populations surged after exposure to the toxic chemicals. The same research also looked at how other bee species dealt with the insecticide and saw mixed population responses. In the U.S. many of these less-adaptable bee species thrive off the peripheral plants where neonicotinoids ended up. This suggests more delicate insect species may be suffering from exposure to the chemicals as well.“That was probably the worst news in this paper,” Colla says.

Despite Zayed’s hopes, the debate over neonicotinoids will likely continue. A total consensus in science is almost impossible, Krupke explains, and is not necessarily the point of the Canadian and European studies. But still, the assumption pesticides do not harm any animals besides their intended target pests, Krupke says, “is increasingly difficult to make with research like this.”