All Episodes
Previous Next
Plain Text
May 21, 2019 - Skeptoid
18:12
Skeptoid #676: Glyphosate and Behavioral Economics

How misinformation spread over one of the safest herbicides becoming known as one of the most harmful. Learn about your ad choices: dovetail.prx.org/ad-choices

Transcriber: nvidia/parakeet-tdt-0.6b-v2, sat-12l-sm, and large-v3-turbo
|

Time Text
Glyphosate Safety Evidence 00:08:32
Unless you're a scientist or a farmer, chances are high that you've been persuaded that glyphosate, the world's most popular herbicide and the active ingredient in Roundup, is poisonous or otherwise harmful to humans.
Every speck of science that exists on the subject shows that it's completely safe.
So how did such misinformation become so popular?
Well, the answer lies, at least in part, in behavioral economics.
And we're going to find out all about it right up next on Skeptoid.
A quick reminder for everyone, you're listening to Skeptoid, revealing the true science and true history behind urban legends every week since 2006.
With over a thousand episodes, we're celebrating 20 years of keeping it focused and keeping it brief.
And we couldn't have done it without your curiosity leading the way.
And now we're even offering a little bit more.
If you become a premium member, supporting the show with a monthly micropayment of as little as $5, you get more Skeptoid.
The premium version of the show is not only ad-free, it has extended content.
These episodes are a few minutes longer.
We get rid of the ads and replace them with more Skeptoid.
The Extended Premium Show available now.
Come to Skeptoid.com and click Go Premium.
You're listening to Skeptoid.
I'm Brian Dunning from Skeptoid.com.
Glyphosate and Behavioral Economics It's hardly possible to turn on the news, to talk to a farmer, or to visit a nursery without hearing something about glyphosate, the active ingredient in many of the world's most popular and effective herbicides, like Roundup, Pronto, Eraser, and 750 other products.
If you've ever heard of these products, you've probably already heard a thousand times that the science shows no risk associated with glyphosate, despite a single committee from the World Health Organization listing it as a probable carcinogen, and despite prominent court cases awarding billions of dollars to cancer victims with the finding that the cancer was caused by glyphosate.
So we're not going to rehash that same science versus pop culture argument again.
Instead, we're going to look at the science behind how this misinformation spread to the point that a huge proportion of people in the world believe a harmless product is harmful.
The result is very likely to be that we will see more bans of glyphosate, requiring farmers to revert to the older, less effective, and actually dangerous herbicides.
The story of glyphosate misinformation is the perfect example of what I like to call the endarkenment, the modern rejection of science and facts in favor of misinformation.
Glyphosate was first registered for use in the United States in 1974 and quickly swept the farming industry.
It was safe for humans and wildlife, so there were no environmental concerns about its use.
It decomposed into the natural products carbon dioxide, phosphoric acid, and ammonia.
And it killed virtually every weed in a crop field, reducing tilling and erosion.
Farm Chemicals magazine named Roundup one of its top 10 products that changed the face of agriculture.
And its inventor, Dr. John Franz, was inducted into the National Inventors Hall of Fame.
Glyphosate's inherent safety to people and animals came from the fact that it includes no ingredients that are harmful.
Its mechanism blocks one very specific metabolic process called the shakimic acid pathway that is present only in photosynthesizing plants and some microorganisms and is not present at all in humans and animals.
Glyphosate does not pass through your skin and if ingested, it does not bioaccumulate and it passes right through without being digested or metabolized.
Taken all into account, it is not surprising that 40 years as one of the most common herbicides on the planet has resulted in not a single observable health consequence.
This is just what we'd expect to see, as glyphosate only interacts with structures not present in humans and animals.
The latest data published in HAZMAP, a service of the U.S. National Library of Medicine, states, There is no association between glyphosate exposure and non-Hodgkin's lymphoma.
There is little evidence of biological effects of glyphosate in humans.
Therefore, no clear biologic mechanism has been proposed.
As far as the agriculture industry is concerned, glyphosate truly is the bees' knees of herbicides.
It is tremendously effective at improving crop yields and reducing costs.
And not only has no evidence of harm to humans ever been observed, nobody has ever even been able to propose a plausible mechanism by which it might.
Then, in 2015, the United Nations IARC, the International Agency for Research on Cancer, added glyphosate to its list of compounds in Group 2A of its classifications of carcinogenic agents.
Group 2A, though it's titled Probably Carcinogenic, is defined as meaning there is limited or inadequate evidence of carcinogenicity.
It's distinct from Group 1, which is for compounds defined as having sufficient evidence of carcinogenicity.
Every other major health and science organization worldwide, plus over 800 studies, disputed this classification, and criticism came fast, notably that the IARC had excluded the vast majority of those 800 studies and included only a very few small ones, and that theirs had been a hazard assessment rather than a risk assessment.
Now, to you and me, the difference between hazard and risk may seem meaningless, but the terms are quite distinct in the science of toxicity assessment.
The moon Io might be a hazardous place to be, but your risk of dying on Io is basically zero.
And although the IARC is only one of scores of such bodies around the world, and still the lone outlier to suggest that glyphosate might be harmful to some, attorneys were fast to react.
They went out and searched for everyone who had non-Hodgkin's lymphoma and who had worked on a farm applying Roundup.
Soon there were over 4,000 lawsuits filed against Monsanto, the producer of Roundup at the time.
The actual number of lawsuits isn't known.
Some sources report it as over 11,000.
Despite the actual data being unassailable, that as Roundup entered the market and its usage increased dramatically over the years, there is absolutely no corresponding increase in the rates of non-Hodgkin's lymphoma or any other cancer or any other disease among farm workers or anyone else.
Eventually, one team of lawyers managed to prevail in court and a worker was awarded hundreds of millions of dollars.
The precedent thus established, at least two other cases have been won as of this writing, awarding damages exceeding $2 billion so far.
Juries don't assess science.
They choose a winner between teams of arguing lawyers.
As no science or statistics can support the finding, it's likely that all these cases will be overturned on the inevitable appeals.
However, the fact remains that the belief that glyphosate is harmful has swept the general public.
So now let's dig into how there came to be opposition to glyphosate in the first place, as by any measure, it's safer than virtually every other effective herbicide ever developed.
It is arguable that most people, including those who are either passionately for or against glyphosate, do not know very much about its chemical makeup, its biochemical mechanism within the weed, or the details of the published research on its safety.
Information Cascades and Decisions 00:07:28
And yet these people still cling to a polarized position, often strongly.
And clearly, glyphosate is not the only such science question where we observe this behavior.
We see it in topics such as water fluoridation, BPA in plastic food containers, the sweetener aspartame, vaccine safety.
The list goes on and on.
Even the flat earth.
What is the societal mechanism by which large numbers of people form shared opinions on things they know very little about?
Hey everyone, I want to remind you about a truly unique and once-in-a-lifetime adventure.
Join me and Mediterranean archaeologist Dr. Flint Dibble for a skeptoid sailing adventure through the Mediterranean Sea aboard the SV Royal Clipper, the world's largest full-rigged sailing ship.
This is also the only opportunity you'll have to hear Flint and I talk about our experiences when we both went on Joe Rogan to represent the causes of science and reality against whatever it is that you get when you're thrown into that lion pit.
We set sail from Málaga, Spain on April 18th, 2026 and finish the adventure in Nice, France on April 25th.
You'll enjoy a fascinating skeptical mini-conference at sea.
You'll visit amazing ports along the Spanish and French coasts and Flint will be our exclusive onboard expert sharing the real archaeology and history about every stop.
We've got special side quests and extra skeptical content planned at each port.
This is a true sailing ship.
You can climb the rat lines to the crow's nest, handle the sails.
You can even take the helm and steer.
This is a real bucket list adventure you don't want to miss.
But cabins are selling fast and this ship does always sell out.
Act now or you'll miss this once-in-a-lifetime opportunity.
Get the full details and book your cabin at skeptoid.com slash adventures.
Hope to see you on board.
That's skeptoid.com slash adventures.
One method is what behavioral economists call an information cascade.
Behavioral economics is a fascinating field.
Where classical economic theory models rational decision-making, behavioral economics looks at the human weaknesses that compel us to make irrational decisions.
We're all susceptible to biases, emotions, cultural influences, cognitive errors, and a whole raft of factors that result in bad decision-making.
In an information cascade, people make a simple decision based only upon an observation of someone else making that decision, like dominoes toppling in a great big expanding fan.
The way it works is this.
A person hears about glyphosate and that it is somehow controversial.
The average person has little to no skin in the game for whether glyphosate is harmful or not, so there's no reason for them to take the time and energy needed to learn how to properly research the question.
The cost in time and energy is too high for little meaningful benefit, so virtually nobody goes to the trouble of informing themselves.
Instead, they observe the choice made by somebody else.
When we see someone else make a decision that we don't know how to make ourselves, we assume they know more than we do, so it's natural for us to adopt their decision.
Almost all the noise in pop culture about glyphosate is negative, so the natural and expected result, predicted and well explained by behavioral economics, is that many people will decide that glyphosate is unacceptably harmful, and other people will observe that decision and make the same one.
Soon, we see exactly what we observe today.
A huge proportion of people who do not understand the science believe glyphosate is harmful.
This is, of course, not a comprehensive discussion of information cascades.
There are other factors and provisos governing when and how they occur and are most effective.
For example, it's important that each member of the cascade has only limited knowledge of the person whose decision they mimic.
They know only that that person made a decision and have little information about why they made it.
To learn more about how information cascades play a huge role in so many popular false beliefs, see the references on the transcript of this episode at skeptoid.com.
The result is that we are now where we are.
There are countless consumer groups informed by this information cascade who list glyphosate as carcinogenic, and countless lobbying groups for the organic industry who say the same.
Armed with white papers from these groups, plus the single lonely scientific finding by the IARC, glyphosate opponents now march the earth, seeking out additional misinformation that confirms their preferred conclusion and adding it to their arsenal.
Bans on glyphosate are already appearing around the world and will probably continue.
It's important to remember that laws and regulations are not informed by science.
They are informed by whatever a bureaucrat was persuaded to do for whatever reason.
Bureaucrats and lawmakers are as susceptible to fallacious information cascades as anyone else.
In fact, they're a prime example of it.
Their aides advise them how to vote, and they're too busy with other matters to open an investigation into how and why that recommendation was given.
The result of these bans is that farmers are required to go back to older generation herbicides, which have been supplanted because they're either not as effective, too expensive, actually harmful to people and animals, or even all three.
One measure of the toxicity of a compound is its LD50.
Higher numbers are safer, lower numbers are more toxic.
Two of the main fallback herbicides for farmers who are not allowed to use glyphosate are dichot and glufosinate.
Glufosonate has an LD50 of 83, a low number, meaning it's quite toxic.
Daquat has an LD50 of 120, slightly safer.
Glyphosate rings in at, wait for it, 6,800.
In other words, the chemicals that the anti-glyphosate lobby wants farmers to use instead are about 100 times as toxic.
This is what happens when we allow emotion-driven policy, or anecdote-driven policy, or popular opinion-driven policy.
A worse outcome in almost every case.
Data-driven policy, policy informed by classical economics instead of behavioral economics, is sadly all too often a unicorn.
Bans on glyphosate are equivalent to personal conviction exemptions from vaccination, equivalent to more expensive BPA-free water bottles, equivalent to San Francisco's warning labels on cell phones.
Emotion Drives Bad Policy 00:02:09
At best, they misinform.
At worst, they do real harm.
A great big Skeptoid shout-out to premium members Dan the Princess Man, Vincent and Sugar Snookums, Yay Nagadai Mite, how you gone, and of course, Bear from New York.
These totally real and not-at-all-nicknamed individuals are among those who make Skeptoid possible for all the rest of us.
Skeptoid is supported by private grants and donations from listeners just like you.
So if you've got a weird nickname, or even if you don't, come to skeptoid.com and click Go Premium.
Your support will bring the show to an average of 100 new listeners.
You're listening to Skeptoid, a listener-supported program.
I'm Brian Dunning from Skeptoid.com.
Hello, everyone.
This is Adrian Hill from Skookum Studios in Calgary, Canada, the land of maple syrup and mousse.
And I'm here to ask you to consider becoming a premium member of Skeptoid for as little as $5 per month.
And that's only the cost of a couple of Tim Horton's double doubles.
And that's Canadian for coffee with double cream and sugar.
Why support Skeptoid?
If you are like me and don't like ads, but like extended versions of each episode, premium is for you.
If you want to support a worthwhile nonprofit that combats pseudoscience, promotes critical thinking, and provides free access to teachers to use the podcast in the classroom via the Teacher's Toolkit, then sign up today.
Remember that skepticism is the best medicine.
Next to giggling, of course.
Until next time, this is Adrienne Hill.
From PRX
Export Selection