Praised for its ability to kill insects effectively and cheaply and reviled as an ecological hazard, DDT continues to engender passion across the political spectrum as one of the world’s most controversial chemical pesticides. In DDT & the American Century: Global Health, Environmental Politics, and the Pesticide That changed the World, David Kinkela chronicles the use of DDT around the world from 1941 to the present with a particular focus on the United States, which has played a critical role in encouraging the global use of the pesticide.
In the following excerpt from DDT & the American Century (pp 15-16, 17-18), Kinkela traces the discovery of the chemical and its development for widespread use during World War II.
DDT was an unlikely hero of the war. In 1939, Paul Müller, a relatively unknown scientist working for the Swiss chemical company Geigy A.G., made a remarkable discovery. Charged with finding and agricultural chemical to control the Colorado potato beetle, an invasive species that threatened the important Swiss crop, Müller uncovered a chemical formula developed nearly seventy years earlier, in 1874. At that time, Othmar Zeidler, a graduate student at the University of Strasbourg, synthesized a crystalline compound, combining chloral hydrate with chlorobenzene in the presence of sulfuric acid. Zeidler’s innovation was dichloro-diphenyl-trichloroethane, more commonly known as DDT. Because Zeidler’s synthesis was only an experiment to fulfill his thesis requirement, he did not recognize the insecticidal properties of the compound. Consequently, his work was shelved.
Years later, when Müller rediscovered the chemical formula, he was immediately amazed. Initial tests demonstrated DDT’s efficacy against Müller’s test subjects, houseflies. What amazed Müller more than DDT’s immediate effectiveness was its persistency. Day after day, Müller returned to the laboratory to find dead flies in the experimental container that had been treated with DDT only once. Encouraged by these findings, Geigy immediately deployed DDT on infested potato fields. Almost magically, the Colorado potato beetle infestation ended within a year. By 1940, DDT proved to be an effective agricultural pesticide with seemingly limited or no toxicological impacts on humans.
But Müller’s discovery generated little international publicity. Europe was engulfed in a continental war, and the United States remained an interested observer. But as the United States entered the war, which expanded across continents and into the tropics, where the threat of insect-borne diseases increased, military health officials on all sides of the conflict demanded new methods to control disease, and DDT was positioned to play an important role in the war effort.
At the start of the war, pyrethrum, a botanical compound derived from chrysanthemum petals, seemed to offer much promise. A popular and effective insecticide, pyrethrum had been used to control body lice during the Napoleonic wars and remained a widely used form of pest control in the United States. American chemical producers proclaimed that pyrethrum offered soldiers “Freedom from Pestilence.” Enlisting “Jonny Pyrethrum,” another U.S. manufacturer notes, demonstrated that the chemical industry was “doing a big job for Uncle Sam in controlling the pest that affects the health of our men on every war front—yes pyrethrum is on malaria patrol.”[ref]Advertisements in Soap and Sanitary Chemicals, January and February 1944.[/ref]
Such optimism would be short lived. By 1939, the U.S. imported 13.5 million pounds of pyrethrum from two major producer-nations, Kenya and Japan, with Japan producing over 90 percent of the chrysanthemum blossoms.[ref]Tsutsui, “Landscapes in the Dark Valley,” 297-311.[/ref] The war brought an abrupt end to the Japanese market and, as the war progressed, Kenyan production could not keep up with demand. As a result, U.S. military officials looked to military and civilian scientists to develop an alternative insecticide.[ref]Pat Jarrett, “The Story of Pyrethrum,” Agricultural Chemicals vol. 1 (December 1946), 27-30, 49.[/ref] Brigadier General James S. Simmons, army chief of preventive medicine, informed a group of civilian researchers that the most important thing they could do for military medicine was to find “a substitute for pyrethrum.”[ref]Quoted from Russell, War and Nature, 127. Russell’s book is perhaps the most comprehensive study of the military control of insect pests. As he accurately demonstrates, the language of eradication and annihilation served a dual purpose that merged military and public health work during the Second World War. I argue that health rather than annihilation is an important trope to examine in this period.[/ref]
Finding the substitute for pyrethrum would fall under the jurisdiction of the Bureau of Entomology and Plant Quarantine (BEPQ) [part of the U.S. Department of Agriculture (USDA)].
[ . . . ]
The scientific and institutional linkages developed for disease prevention and control during the war were not limited to the United States; they were in fact global. Rather than being an isolated research station, the Orlando laboratory [of the BEPQ] was part of an international network of scientists focusing on limiting the impact of insect-borne infections during the war. Research conducted by military and civilian scientists in Mexico, Brazil, Trinidad, Australia, Algeria, Egypt, and Italy developed new understandings of disease within different environments. This expansive scientific undertaking would ultimately reshape the postwar period. Yet, during the war, U.S. science remained steadfast in its commitment to vanquish foreign enemies, human and insect alike.
[Edward Fred] Kipling and his fellow scientists at the Orlando laboratory faced the sea of disease head-on and were determined to navigate and conquer the treacherous world that lay beyond U.S. borders. The enormous promise of DDT provided a means to envision this victory, but much was unknown about the chemical few had ever heard of. The question was whether DDT could fill the vacuum left by the undersupply of pyrethrum.
Despite the limits of initial wartime markets, the Swiss manufacturer Geigy attempted to capitalize on Müller’s discovery. In 1940, Geigy began marketing two DDT products; one was a louse powder called Neocid, and the other a spray insecticide sold under the name Gesarol. Used primarily as agricultural agents within Switzerland, Neocid and Gesarol provided remarkable protection against a number of insect pests. Building on the success of early experiments, Geigy provided samples to Allied and Axis powers, and in so doing set off a series of experiments linking DDT to diverse ecologies, insects, and human bodies. It was a turning point for public health.
From DDT & the American Century: Global Health, Environmental Politics, and the Pesticide That Changed the World by David Kinkela. Copyright (c) 2011 by the University of North Carolina Press.
David Kinkela is assistant professor of history at the State University of New York-Fredonia.