The Story of DDT

Think for a moment about the last time you had a bad case of the flu: the headaches, the chills, the vomiting, the congestion, the depressed mood, the inability to function normally for days. But imagine it felt 10 times worse, and lasted for months or years, robbing you of anything resembling a truly human life.

That is life for the hundreds of millions of people who live with–and often die from–malaria.

The malaria parasite is one of nature’s cruelest torturers. Acquired from the bite of the common Anopheles mosquito, this parasite enters the bloodstream and, left to its own devices, wreaks havoc on the lives of its human hosts.

In its milder forms, the malaria parasite leads to cycles of different symptoms including fever, sweat and chills, muscle pains, shock, and breathing problems. More dangerous variants lead to liver failure, coma, and brain damage. And, of course, there are the deaths–millions and millions of individual lives ended prematurely, usually after enough suffering to make death a relief. The most common malaria deaths afflict the most vulnerable–children under 5, pregnant women, and individuals who are already weakened by malnutrition or other diseases.

When you hear of “living in harmony” with nature, remember this: nature gives us unmitigated malaria, while human ingenuity and industry gave us the ultimate weapon against malaria–the industrial, “artificial” chemical DDT. As the National Academy of Sciences said in the 1970s, “[T]o only a few chemicals does man owe as great a debt as to DDT…in little more than two decades, DDT has prevented 500 million human deaths, due to malaria, that otherwise would have been inevitable.”

In 1939, Paul Müller discovered that Dichloro-Diphenyl-Trichloroethane, or DDT, is an effective chemical agent against insects such as flies, mosquitoes, and beetles. gives a good account of the story.

Müller was an independent scientist often referred to in the labs as a lone wolf…Two events occurred that influenced his research into insecticides. The first was a severe food shortage in Switzerland, which demonstrated the need for better insect control of crops. The second event was the Russian typhus epidemic, the largest typhus epidemic in history. Müller, with his background in chemistry and botany, found himself both motivated and prepared for the challenge.

He worked for J.R. Geigy (which eventually became today’s drug giant Novartis), developing tanning methods for protecting clothes from insects, and a safe seed disinfectant that wasn’t based on poisonous mercury compounds, as was common in his era. After these successes, he decided to pursue the perfect synthetic insecticide. He absorbed all the information possible on the subject, came up with properties such an insecticide would exhibit, and set forth on his solitary quest to find it. After four years of work and 349 failures, in September of 1939, Müller placed a compound in his fly cage. After a short while the flies dropped and died. What he had found was DDT.

Others quickly used Müller’s work, which went on to win the Nobel Prize in Medicine, to combat insect-borne diseases. In one success story, 1.3 million people were treated with DDT to defeat a typhus epidemic in Naples during the winter of 1943/44 that no other treatment could stop. The DDT killed the lice that carried the disease, stopping the epidemic at its root. So began an epic war against nature’s deadliest insects.

DDT was a revolution in both effectiveness and safety. Prior to DDT and other modern pest control agents, pesticides typically included poisons such as arsenic or cyanide, which often did more harm than good. Because DDT was the result of industrial engineering and scientific selection aimed specifically at fighting bugs and benefiting humans, it provided a new level of effectiveness and safety. It could kill bugs but be eaten safely by humans.

DDT has numerous qualities desirable in an insecticide. It is a white, almost odorless powder that does not easily break down, even over long periods of time and is only slightly soluble in water. Once DDT was deployed in a given area, it could win enduring victories over deadly insects. Thus, it was used amply; direct deployment on the human body, spraying of parasite-infested areas, inside homes, mosquito-breeding waters, and large-scale deployment over crop fields were commonplace in the early years of use in the US.

Today great efforts are made to find a viable vaccine against malaria and to improve medical treatments for those who have contracted it. But the disease is not an easy target. There are many strains of the parasite and several variants of the Anopheles mosquito can serve as a carrier. Due to the short life-cycles of mosquitoes the malaria parasite can spread rapidly. Fortunately, DDT continues to prove reliable 70 years after its introduction, possessing a mixture of qualities unmatched by alternatives. Its longevity minimizes repeat treatments, further increasing reliability as well as affordability. Its safety for humans and animals makes it usable inside homes and close to potential malaria victims. And DDT has multiple ways of stopping deadly insects; even those that develop a resistance to its poison are still repelled by it.

The historical record is definitive on all these counts. In the decades following Müller’s discovery, DDT proved highly versatile at defeating insect-borne diseases. By the 1960s, thanks to widespread deployment of DDT, malaria was essentially eradicated in the developed world. Acquiring malaria in the Western world today is unthinkable, but in the 1930s it was commonplace. Malaria had been widespread even in industrialized countries, where it killed thousands every year and infected many more. The popular misconception that malaria is only a tropical disease is only plausible because DDT eradicated malaria from northern latitudes within a generation. And DDT’s beneficent impact went far beyond malaria. It has proved effective against many other insect-borne diseases, such as yellow fever and typhus.

Poor countries also benefited greatly from DDT. In Sri Lanka, malaria declined from 2.8 million cases and thousands of deaths in 1948 to fewer than 30 cases and zero deaths in 1964. In India the annual death toll declined from many hundreds of thousands in 1935 to about 1,500 in 1975.

The list of success stories in developing countries is lengthy. With few exceptions, DDT proves effective wherever it is used, and malaria cases spike where its use is discontinued.

A more recent example is South Africa, where DDT was successfully used for malaria control from 1946 to 1996. After switching to another insecticide the cases increased 80-fold. In 2000 DDT was reintroduced and demonstrated its effectiveness once more, reducing cases significantly from a peak in 2000-2001 of more than 60000 cases and more than 400 deaths to less than 6000 cases and only 37 deaths in 2007. The alternative pesticide–synthetic pyrethroids–was unable to match DDT’s results.

Unfortunately, despite the heroically positive impact of DDT, the modern environmentalist movement made this agent of life its number one target in the 1960s. In her famous book Silent Spring the environmentalist icon Rachel Carson chose, of all the features of industrial capitalism, DDT to demonize. Evading its benefits for billions, she made allegations about detrimental effects of DDT and other pesticides on human health and that of various other species (especially birds), based on junk science and anecdotes.

Revealingly, an intellectual and media establishment bred with anti-industrial hostility accepted Carson’s narrative. Blinded to the good of DDT and eager to seize on Carson’s bizarre characterization, they made her a cultural hero, which she remains today.

Although none of Carson’s claims could withstand scrutiny, not even those about birds, the damage in public opinion was catastrophic. In the late 1960s and early 1970s, environmentalist and conservationist groups such as the Audubon Society and the Sierra Club spearheaded a call for a DDT ban.

In 1972, after 7 months of investigation of DDT by the newly founded Environmental Protection Agency (EPA), EPA administrative law judge Edmund Sweeney ruled against a ban. He found, based on the science presented, that “DDT is not a carcinogenic hazard to man,” “DDT is not a mutagenic or teratogenic hazard to man,” “The use of DDT under the regulations involved here do not have a deleterious effect on freshwater fish, estuarine organisms, wild birds or other wildlife,” and that “The evidence in this proceeding supports the conclusion that there is a present need for the essential uses of DDT.”

But EPA head William Ruckelshaus, overruled Sweeney and banned DDT for general use, stating that “the long-range risk of continued use of DDT… is unacceptable and outweighs any benefits,” a statement based on blind anti-industrial ideology defying scientific evidence and decades of experience with widespread DDT use in the US and elsewhere.

Ruckelshaus never attended the 7 month investigation’s hearings. But he did apparently read Silent Spring; in his opinion and order he credited Rachel Carson’s book for raising awareness of the widespread use of DDT and other pesticides.

This marked a major political victory for the environmentalist movement. Although the case against DDT was not based on observable facts and sound science, the greens had acquired political influence.

Ironically, DDT’s success made it easier to demonize. As malaria and other diseases vanished from the industrialized world, the need for DDT was not as immediately perceivable. Western populations became more susceptible to scare stories about industrial chemicals, while oblivious to those chemicals’ life-saving benefits.

One example was the claim–often repeated today–that birds of prey, in particular the Bald Eagle, suffered from eggshell thinning and other effects of DDT, allegedly bringing them to the brink of extinction. As it turns out, the Bald Eagle had been threatened with extinction at least since the early 1920’s, more than 20 years before the first deployment of DDT, and increased in numbers during peak years of US DDT deployment. The connection between eggshell thinning or other detrimental effects and DDT could not be established by following scientific investigations.

Another common environmentalist critique of DDT is that insects develop resistance to it. (This claim was made by Greenpeace’s Ryan Rittenhouse in a recent debate with CIP’s Alex Epstein.) While resistance is a real problem with all chemicals used for controlling insect-borne diseases, DDT again proves superior to alternatives. In addition to its poisoning effect DDT also works as a repellent even if the insects have acquired resistance to it.

Even if these allegations were true they would not justify banning a pesticide with DDT’s track record of enormous benefits. The absence of facts behind the attacks on DDT indicates that environmenalists attack it not out of a concern for human safety, but on an ideological hatred of industrial chemicals.

Parallel to the propaganda efforts to demonize DDT as a dangerous and highly toxic substance, aid organizations and governments applied pressure to halt third-world countries from using DDT to save their citizens. A recent example is Uganda where in 2004 the EU threatened “dire consequences” for the country’s exports if the western anti-DDT standards weren’t met.

Influenced by donor agencies like the United States Agency for International Development (USAID), international bodies like the United Nations Environment Programme (UNEP), and other organizations, countries that depended on the aid were inclined to stop using DDT or not introducing it for disease-control. Belize and Bolivia, among others, have dropped the use of DDT out of fear of losing foreign subsidies.

Declining worldwide use of DDT also resulted in less availability for poor countries. India is the only country left producing DDT in large amounts. To combat this problem 15 African countries recently declared they would start producing the chemical for use against malaria mosquitoes.

Instead of encouraging the proven and effective DDT, a concerted effort was made to promote alternatives such as insecticide-impregnated bed nets and vaccines. The results failed to reach the promised levels. Subsequently, the World Health Organization (WHO), thanks to the influence of anti-malaria advocates on public opinion, changed its guidelines to encourage a more widespread use of DDT, acknowledging the unreasonable fear of environmental and health impacts. According to their own press release that constituted a “reversing” of their policy.

In 2001 at the Stockholm Convention to ban persistent organic pollutants (POPs), also named the “dirty dozen” and including DDT, environmental organizations demonstrated their opposition against DDT for any use. The World Wildlife Fund (WWF), Greenpeace, UNEP, Physicians for Social Responsibility, and many others advocated against an exemption allowing DDT use for human health. Thanks to resistance of developing countries and anti-malaria advocates they had to back down.

Despite recent efforts of environmental groups to re-write their history on DDT, the record is clear. Their advocacy against DDT was never based on facts and sound science but on their anti-industrial, ultimately anti-human ideology. Their stated goal was and continues to be to get rid of this marvellous chemical because it constitutes a fundamental modification of nature by man, not because it does actual harm that outweighs the benefits of its use.

The result of this ideology-driven campaign against the use of DDT is an re-emergence of malaria in places where it was believed to be under control and the continuing high death toll in places where it was not effectively used yet, namely sub-Saharan Africa, parts of South America and Asia.

At its peak malaria infected hundreds of millions of people and killed over one million every year during the past decades. Today it is estimated that still about 650,000 human beings die every year from it. Many of these victims could likely have been avoided had the campaign against DDT not taken place and the success story of this pesticide been allowed to continue and spread into the poorer regions of the world.

The only way to stop the carnage is to embrace DDT, and industrial progress more broadly, as agents of human prosperity and happiness.


Steffen Henne is a Researcher for the Center for Industrial Progress