There were also the tragic accidents associated with the increased presence of pest poisons in everyday life, such as the death of 47 patients at an Oregon hospital where roach powder was confused for powdered milk. Instead of distancing themselves from poison sprays, however, by World War II more and more American consumers were bringing them home from the corner store.
As Americans planted victory gardens to grow their own food, they amassed household-sized collections of agricultural poisons, including lead arsenate, calcium arsenate, nicotine sulfate, bichloride of mercury, and Bordeaux powder, a mixture of copper sulfate and lime. Insecticides, by definition, were poisons, and consumers were used to thinking of them as such despite their growing ubiquity. DDT thus posed an unparalleled paradox. But for every feature that set it apart from the earlier insecticides, it was still a substance meant to kill.
When the pesticide was first released for sale, state officials in Missouri issued a formal warning against it, citing unknown hazards to plants, animals, and humans. Minnesota banned its sale, New Jersey restricted it, and California and New York issued decrees requiring that DDT-containing products bear the skull and crossbones indicating a dangerous poison.
If people learned through experience that DDT could be handled with less caution than such bona-fide poisons as strychnine and bichloride of mercury—which it certainly could—they would lose their respect for the skull and crossbones as a signifier of danger. As states struggled to regulate DDT, journalists struggled to reconcile warnings and promises.
In the years just after the war Colson launched a dogged investigation into DDT, writing to state agencies, manufacturers, and organizations far and wide. The literature she amassed on the pesticide indicated that it might be harmful to humans but offered no conclusive proof that it was.
And the more experts she questioned, the more she was told that DDT had above all saved countless lives around the globe, all while never harming a person. Army soldiers demonstrating DDT-spraying equipment. To her this was reason enough to worry. They noted early on as National Geographic had reported that DDT was deadly to honeybees, butterflies, small fish and reptiles, and, in high enough concentrations, birds and small mammals.
Death to pollinators would lead to fruitless orchards and barren crop fields. As a report by the U. Such expert worries were no secret. Newspapers far and wide reported that the new chemical was a threat to nature. Older agricultural chemicals, such as lead and arsenic, typically got press space only when they poisoned people. The stories we tell over and over again, like that of DDT, explain how we arrived at the present, and they point to a hoped-for future.
The decline in DDT usage was the result of 1 increased insect resistance; 2 the development of more effective alternative pesticides; 3 growing public concern over adverse environmental side effects; and 4 increasing government restrictions on DDT use. In addition to domestic consumption, large quantities of DDT have been purchased by the Agency for International Development and the United Nations and exported for malaria control. DDT exports increased from 12 percent of the total production in to 67 percent in However, exports have shown a marked decrease in recent years dropping from approximately 70 million pounds in to 35 million in Certain characteristics of DDT which contributed to the early popularity of the chemical, particularly its persistence, later became the basis for public concern over possible hazards involved in the pesticide's use.
Although warnings against such hazards were voiced by scientists as early as the mids, it was the publication of Rachel Carson's book Silent Spring in that stimulated widespread public concern over use of the chemical.
After Carson's alert to the public concerning the dangers of improper pesticide use and the need for better pesticide controls, it was only natural that DDT, as one of the most widely used pesticides of the time, should come under intensive investigation. Throughout the last decade, proponents and opponents of DDT have faced one another in a growing series of confrontations. Proponents argue that DDT has a good human health record and that alternatives to DDT are more hazardous to the user and more costly.
Opponents to DDT, admitting that there may be little evidence of direct harm to man, emphasize other hazards connected with its use. They argue that DDT is a persistent, toxic chemical which easily collects in the food chain posing a proven hazard to non-target organisms such as fish and wildlife and otherwise upsetting the natural ecological balance.
All four reports recommended an orderly phasing out of the pesticide over a limited period of time. Public concern further manifested itself through the activities of various environmental organizations.
Beginning in , the Environmental Defense Fund, the National Audubon Society, the National Wildlife Federation, the Izaak Walton League and other environmental groups became increasingly active in initiating court proceedings leading to the restriction of DDT use at both local and Federal levels.
Although the remaining States have provisions for the "restricted use" classification of pesticides, no specific mention is made of DDT. JavaScript appears to be disabled on this computer. Please click here to see any active alerts. DDT dichloro-diphenyl-trichloroethane was developed as the first of the modern synthetic insecticides in the s.
It was initially used with great effect to combat malaria, typhus, and the other insect-borne human diseases among both military and civilian populations. It also was effective for insect control in crop and livestock production, institutions, homes, and gardens. DDT's quick success as a pesticide and broad use in the United States and other countries led to the development of resistance by many insect pest species. The U. DDT has humble origins for a chemical that would eventually reach much of the world.
First discovered in by a German chemistry student named Othmar Zeidler, the compound did not receive serious attention until a year-old chemist named Paul Herman Muller synthesized it again in Muller developed the chemical while trying to identify the particular toxic ingredient in two other insecticides that he had recently invented, Gesarol and Neocid 1. His investigation eventually yielded dichlorodiphenyltrichloroethane, which he named DDT.
Over the next several decades, DDT would become one of the most significant and controversial chemicals of the twentieth century.
The early use of DDT during World War II enjoyed an almost reverential following, but its rampant and often indiscriminant deployment quickly generated significant criticism. The history of DDT in the United States reveals many of the ways in which science has been manipulated and controlled throughout history; calls into question many con- ventional assumptions about the relationships between science, society, and nature; and raises important questions about modern public health programs around the world.
DDT use first began in earnest in the s, pro- pelled largely by the need to protect American soldiers from tropical diseases overseas. The chemical had already proven to be an effective pesticide during efforts to control Colorado potato beetles before the Second World War. Many researchers marveled at how potent even the smallest doses of DDT could be.
Unlike many other insecticides, DDT would continue to kill insects for long periods of time, even after it was left sitting for days.
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