- Growing up, we're educated on the power of science to explain the physical world, but today's guest offers a more complex view of the role of science and public life and the stories it offers all of us as we grapple with everything from pesticides to vaccines, and even climate change.

She's Elena Conis, this week (upbeat ambient music) on Story in the Public Square.

Hello, and welcome to a Story in the Public Square, where a storytelling meets public affairs.

I'm Jim Ludes from the Pell Center at Salve Regina University.

- I'm G. Wayne Miller with the Providence Journal.

- This week, we're joined by Elena Conis, a professor at the University of California, Berkeley who's the author of "How to Sell a Poison: The Rise, Fall, and Toxic Return of DDT".

She joins us today from California.

Elena, thank you so much for being with us.

- Thank you so much for having me.

It's a pleasure to be here.

- You know, we wanna congratulate you on all of your work.

I saw my parents yesterday however, and mentioned your book to them and their eyes became wide when I mentioned DDT.

I think of a certain generation, that's the response, but for a younger audience, I'm not sure that that response is what happens.

So why did my parents respond the way they did to the mention of DDT?

- I'm not surprised at all that they did.

This was a chemical that we developed during the Second World War and used and abandoned after that war.

And so folks today who were alive during the Second World War after usually have vivid memories of us spraying it all over the place and in every kind of facet and corner of our lives, we sprayed it to kill insects, on farms, but also in homes and communities, on shade trees and parks and fairgrounds.

And we didn't spray just a little bit of it, we sprayed a lot of it.

And then we realized that that was a really bad idea.

So people who remember it being sprayed, probably also remember it being banned and remember the shock of learning that we had used something so essentially carelessly before we knew the full story about its harms.

- Well, we were gonna talk about some of those harms in a little bit, but one of the passages that really sort of struck me and echoed today was the description of using DDT to combat polio.

And so I wonder for the audience, if you would walk us through that a little bit, but in particular, I wanna explore the enthusiasm that people had to try something, anything out of a motivation of fear, which sort of resonated with our experience over the last couple of years.

And we think about hydroxychloroquine and ivermectin, that sort of sounded familiar to me.

- Absolutely.

Yeah, this is such an interesting historical episode that I think has been largely forgotten.

So one of the reasons DDT was so widely used during World War II was because it was so good at killing insects that spread diseases, like malaria typhus, dengue, yellow fever, it killed lice, it killed mosquitoes and a whole host of other insects.

What this meant was that during the war, this pesticide, this chemical acquired a reputation for being, people called this at the time, a wonder drug, a chemical that was capable of protecting people from disease.

And in the war, that meant that troops could go into places where typically malaria would be a bigger threat than enemy combatants, and they wouldn't have to worry about malaria at all.

So we ended the second world war with this idea that DDT was this incredibly powerful way of protecting us from infectious diseases.

Now interestingly, this was a time, mid to late 40s, and then after the war, the early 50s, when we in the US were getting most of our infectious diseases under good control, largely with things like antibiotics and vaccines, diseases like measles, Scarlet fever, et cetera were really on the decline, but there was one exception and that was polio.

And polio was becoming worse and worse by the year.

It was an infectious or communicable disease that largely, but not exclusively affected children.

And it left the sickest children paralyzed, sometimes for life and could be fatal in the worst cases.

So people were desperate to find anything to protect themselves and their families from polio.

Scientists didn't have a good idea how it spread, but one theory was that polio was spread by flies.

So now you can probably put the pieces together in your head.

Very, very quickly, communities came to the conclusion that, well, if this wonder chemical saved the troops, let's use it at home and try to save our communities and our families.

So communities started spraying DDT in the hopes that by killing every fly in sight, they would protect themselves from polio.

To make a very long story short, this practice went on for about a good seven, eight years, long after scientists had studied it closely and said, this isn't working, this is not a way to stop polio, but people were so desperate for something, anything to help them feel safe and protected from the disease that they used it anyway.

And that's certainly something that in many ways, many of us can certainly sympathize with today.

- You know, this episode is a wonderful example of the overall book, which is a wonderful history of science and that push and pull between what we know and what we think we know.

Towards the end of the book, you say that science is social and that resonates here too.

Could you explain that concept to the audience?

- Absolutely.

So science is, just to put it really simply, it's a process.

It's a process that we use for observing and understanding the world around us.

And that process can yield knowledge that can accomplish incredible feats, stop or prevent or cure diseases, put humankind in space, (chuckles) and all the way down to the nano level, but it is simply that, it's a process.

And it's a process that is engaged in by people.

So people bring all of their humanness to the process of carrying about science.

They bring their biases, their hopes, their fears, their assumptions.

One thing that was so interesting to me about the polio episode is that here was an episode in which scientists put forth the theory that polio was spread by flies, and then to the public, that seemed to make sense because flies were associated with quote unquote filth.

Filth seemed to be a way of spreading other diseases, particularly diarrheal diseases, like cholera and the like.

And so it seemed to make sense to people, we kill the fly, scientists said that they might be responsible for spreading polio.

But again, science is a process, but particularly during and after the war, we had looked to it increasingly as a source of firm answers.

And so we were really slow to change course.

As the process unfolded and scientists said, no, wait, hold on, we need to investigate more, we were already and running.

And that's not simply a public problem, there were so many forces at play.

The US Army for instance really wanted to use DDT even though some government scientists during the war said, we need way more time to study it.

It has some effects that are troubling to us.

But in the context of war, the army said, we're not gonna worry about those problems now, we're gonna worry about them later.

So all of this is just a function of what it means to be human, what it means to solve problems today, to interact with other people, to address our fears with the information that we have in the present and see if we can hold onto or postpone how that information might change in the future.

- So from the postwar period until the early 1960s and specifically 1962, when Rachel Carson published "Silent Spring", were there any voices raised that this substance, DDT could be harmful to people and also to other species and also to the environment?

Were there any sort of lone voices out there talking about that?

- Absolutely.

And they actually weren't so alone.

So from the very earliest uses of DDT, some scientists, like some of the government scientists I had mentioned a moment ago, noted that in their own tests, DDT had a couple of characteristics that seemed troubling.

One of the characteristics was that it was very persistent.

You sprayed DDT and you didn't have to spray it again for months.

While the US Army loved this, farmers loved this, but some scientists, specifically entomologists said, well, this is going to be great for bugs that we don't want around, but what about the bugs that we actually need for our survival?

What about the pollinators?

The bees?

If DDT is so persistent, we really have to think about what larger effects its use is going to have on insects as a whole.

And then there were scientists who said, not only is it persistent in the environment, it also seems to be persistent in lab animals.

And some of them noticed that it was accumulating inside some animals that they were studying in the lab.

It was building up in their body fat, and that included their breast milk in the case of female animals.

So there were scientists who said, we need a lot more time to study this.

And then there were the small farmers, particularly after the war, small farmers and beekeepers who started to notice that not only was DDT in much broader use than many of the insecticides that they were used to before the war, it was being used on, in different ways, crop dusts were spraying it over large swaths of land and in some cases, and there's one story that I tell in the book about a small town in Southeastern Georgia, the farmers there began to feel like these chemicals being sprayed from above, and DDT was one of a whole class of chemicals, but the most familiar to the broader public at the time, they began to feel like those chemicals were having effects that they could see on their own farms, killing their bees, harming their baby chicks, making the milk come from their cows taste a little funny, and making them feel not so good when they were inhaling this dust and this spray that was being applied from above.

So small farmers started to protest along with entomologists and others in this one small town in Southeast Georgia, a woman named Duffy Colson tried for years to start what she called a "Health Movement", rallying her neighbors to the cause.

They all signed petitions, they wrote to everybody they could think of, their politicians locally at the state level, all the way up to Washington.

And in the end, Congress did hold hearings, not just on DDT, but on the new chemicals that we were using in the environment and in the food supply generally in the 1950s.

So Rachel Carson's book, we give it a lot of credit for really turning public opinion, but it really represented a kind of build up of all of this protest and concern over time.

- So behind all this is a large market and demand for this product.

And so obviously corporations are manufacturing it and selling it.

Can you tell us who some of those corporations were and what we're talking about in terms of profits or the amount of money that's being made on this during, again, during this period into 1972?

- Absolutely.

- I imagine it's a lot of money was made selling a poison.

- Well, this is a really interesting part of the story, because DDT was actually first synthesized back in the 1870s and then sort of rediscovered for its insect killing properties during the war, it was produced in the US off patent during the war and its chemical formula was published during the war in a scientific journal.

So after the war, pretty much anybody who knew some basic chemistry started to manufacture it.

The big manufacturers had been manufacturing it during the war and continued to after the war, and these included companies we still know of today, like Monsanto, Sherwin Williams, which we largely know is a paint company, Dow, DuPont, and the like.

But also a number of small companies what we still sometimes call mom and pop shops, places that just operated like a small feed and seed or a small local pharmacy, and had a chemist on hand who could mix things, because before the war, people would mix their own pesticides.

And so it made sense to track down DDTs formula and make it for themselves.

What this meant was that for the big companies, for whom making DDT was profitable during the war, after the war, DDT began to become a money loser for them.

Everybody was making it, so the price was falling and falling and falling.

But what these big companies did realize was that there was tremendous appetite for pesticides as we began to call them.

And so these big companies began to invest in newer and better and patented pesticides that they could charge more and more for.

Eventually, to kind of fast forward a few steps, they, for the most part wanted DDT out of the way so that they could bring their proprietary, patented pesticides to market and make more money selling those.

So it's a complicated story.

- It is.

One of the things that I admired about the book was the individuals trying to figure out what was going on in their families and in their communities who kept sort of running into stonewalls and not being able to really understand it.

For our audience today, can you give us a sense of what are the human health consequences of DDT exposure?

- Absolutely.

So to answer that, I wanna go back to Duffy Colson, this small farmer in Southeast Georgia running her farm, trying to run her farm in the late 1940s, and feeling not healthy.

Her complaint was every spring as the crop dusters flew overhead, she would develop headaches, sore throat, runny nose, and just start to feel run down.

Interestingly, around the same time doctors and communities all across the US were starting to notice a strange syndrome that they ended up calling virus X.

They classified it as including a combination of respiratory and gastrointestinal systems combined with fatigue.

And in some cases what felt almost like paralysis.

Virus X has long been forgotten.

But in reading back over these sources, I became very convinced that people were exposed to so many pesticides in such great amounts, that it actually was making them sick in a way that doctors couldn't detect in the clinic.

At the same time however, scientists were still studying DDT and other chemicals in the lab, which largely meant, or often meant looking at their effects in animals.

And they noticed not only was it accumulating in fat, like I mentioned before, not only was it accumulating in breast milk, they also noticed, and it took them a long time to piece this together that it had effects similar to a hormone.

In particular, they noticed reproductive hormones.

And for instance, scientists who gave the chemical and some other chemicals in lab tests to roosters effectively noticed that when those roosters reproduced, they had diminished testicles, smaller cones, in fact, they noted, they started to look more like hens, and it took a long time, decades really before scientists realized that DDT was what we would eventually come to call an endocrine disruptor.

It's a chemical that mimics hormones and can act like a hormone in the body, amplifying or copying some hormones, blocking other hormones.

This is one of just many, many, many chemicals that can do this.

Others actually are better at it than DDT.

But DDT, we didn't really know it was one of the first of the examples of this that we had identified.

What we've learned also over time is that when you're exposed to chemicals that mimic hormones, they can have really profound and really long lasting effects on the human body.

They can affect reproductive development, they can cause changes that can result in cancer down the line.

So DDT eventually was linked to several different forms of cancer.

In the book, I focus on breast cancer in particular, because it's the one where it seems like we had such strong clues early on that we just didn't pick up on, we weren't capable of seeing, but this is just one form of cancer that DDT was linked to.

And DDT was just one of this larger class of endocrine disrupting chemicals to have these effects on humans.

- So DDT was banned in 1972, and by all rights, you would think that would've been the end of the story, DDT is gone, or at least no longer being sold, cannot be sold, but it wasn't the end of the story, and a prominent tobacco company became involved.

Tell us about that, 'cause I found this to be not only revealing, but almost stunning in what came out of that.

- It stunned me, and it's actually a large part of why I was interested in writing a whole book about a chemical that most people don't know about anymore and that we think it has a story of, a case that's been closed or settled.

In the late 1960s, actually the mid to late 1960s, a few social movements started to take on the fight against pesticides, the Farm Workers Movement, the Environmental Movement, and they began to demand greater limits on DDTs use.

Ultimately, one of these movements, the Environmental Movement took their fight to the government.

They took it to the courts and eventually they took it to the government.

And in the early 1970s, the newly formed EPA announced that it was gonna hold what they called consolidated hearings.

And here all of the complaints about DDT and give the manufacturers their turn at defending the chemical, also in these same hearings.

And something really interesting happened here, the chemical companies were actually quite conflicted.

And then behind the scenes, there was another industry involved, the tobacco companies, which nobody saw coming.

But the tobacco companies had been interested in DDT from the start.

This was a chemical that could control lots of pests on tobacco, as it was being grown, as it was being cured and stored in warehouses and transported.

It was vulnerable to all sorts of pests, and DDT seemed to be a good way to keep those pests in check.

It had other effects on tobacco, it actually affected its burn rate and its flavor.

None of these were bad news for the tobacco industry.

However, after "Silent Spring", there was a lot more scrutiny on DDT and this wasn't just happening in the US, European nations and other nations were also looking more carefully at DDT.

But the reason why I highlighted European nations was that they started to pass regulations in the late 1960s.

They started to announce new rules that would limit the amount of DDT allowed on any imported crops.

And that included tobacco.

And in particular, the companies of West Germany and Britain announced that they were going to set DDT limits so low that US tobacco companies would no longer be able to export their products to those countries.

And at the time, those countries accounted for a third of the US tobacco market, a really big figure.

So the tobacco companies wanted farmers to stop using DDT.

They asked their growers to stop using it, but with everybody else still using it and the chemical is so persistent, the tobacco still contained DDT.

So then they too turned to the government and started asking the USDA, could you do something about this?

Interestingly, before we banned DDT at the national level, the USDA announced that it could no longer be used on tobacco and a couple of other crops, but tobacco was one of the earliest national bans.

And this curious fact has been overlooked, but behind the scenes, tobacco had a strong interest in seeing DDTs use completely stopped.

I'll just mention briefly, the big chemical companies too weren't eager to defend DDT in these national hearings, because again, they wanted to sell proprietary chemicals.

They had a whole bunch of on patent pesticides that were gonna be far more profitable than DDT, and they were all too willing to see DDT go and get out of the way.

- Elena, one of the things that, we've got about two minutes left here, but one of the things that struck me was the, I don't wanna call it politicization of science, but the use of science to sow doubt.

You talk about the tobacco industry liking the negative attention on DDT and the chemical industry, 'cause it took some of the heat away from them.

How do consumers sift through all of this information to know what they should do and what they should avoid to protect their families?

- Oh, this is such a good question and such a hard one.

And I need to add one brief part of the story because the tobacco industry that was all too happy to see DDT get out of the way in the late 60s, 25 years later, bankrolled a campaign, a communications campaign to quote unquote, "bring DDT back".

Long story short.

There were a couple of anti tobacco measures globally that were about to go into effect and they wanted the public to distrust global health setting agencies like the WHO, they also wanted the public to think that disease associated with tobacco is not as serious as other diseases.

And so they funded this campaign to get the public to think DDT should never have been banned in the first place and that we needed to bring it back specifically to control diseases like malaria.

Now how can the public know what to think when they don't even understand the forces or the motivations behind some of the communications that they're hearing in the media and in the press?

It's extraordinarily difficult to know.

What I have come away from this story thinking about is the more we know about who's telling us what to believe and why they're telling us what we should believe, the better off we are.

We really need to understand the interests and the motivations of the people who we take as experts and who we'd look to, to explain to us in scientific terms often how to stay safe in this world.

The more we know about their interests, the more we can trust what they're telling us.

Their interests might not always be completely above reproach, but that honesty will go a lot further toward creating trust than I think we've been able to achieve so far.

- Well, Elena, this is a really important read and with a surprising twist at the end.

She's Elena Conis, the book is "How to Sell a Poison".

It is worth the read.

(upbeat ambient music) That's all the time we have this week, but if you wanna know more about Story in the Public Square, you can find us on Facebook and Twitter or visit pellcenter.org where you can always catch up on previous episodes.

For G. Wayne Miller, I'm Jim Ludes, asking you to join us again next time for more Story in the Public Square.