Between and , cases of malaria fell from approximately , to practically none because of the use of DDT. DDT is still used today in parts of South America, Asia, and Africa with the aim of controlling malaria in places that may not be able to afford more expensive and potentially safer alternatives. Because of the ban on DDT in the United States in , restrictions have been applied to its use; DDT can legally be produced in the United States but may only be sold to or used by foreign countries.
Two of the major reasons behind the ban of DDT were the scientific evidence that exhibited buildup in the fatty tissues of wildlife while persisting in the natural environment and proved the existence of an evolutionary resistance that insects began to develop towards the chemical.
Malaria is a mosquito-borne disease that can be found primarily in tropical and impoverished areas of the Earth. It can cause fevers, headaches, and may even lead to death. In , the first stages of spraying were carried out upon nearly , houses, with the goal of reaching nearly three million households by In South America, malaria was the leading health problem in Ecuador, with about half of the population infected by the disease.
Malaria contributed to the three leading causes of infant mortality in Venezuela, which became the first country to begin a national DDT program in Eradication of malaria in Venezuela was reported to have covered , square miles within a population of 2. After Cuba partnered with the Rockefeller Foundation in using DDT to spray the houses, malaria was no longer a major health problem in some of its rural provinces.
Russell of the Rockefeller Foundation. However, in , an increase in anophelism was attributed to the end of DDT application a few years earlier. These case studies of the effectiveness of DDT in controlling malaria show how important international governments considered the insecticide in the fight against infant deaths and rapid population decline.
During the s, rice cultivation in Greece was restricted because of malaria but permitted again in because of the anti-malaria campaign, making rice an export crop for Greece. Daniel E. Wright was considered the pioneer in the use of DDT to control malaria in Greece and became the Lieutenant Colonel of the Public Health Service in as a malariologist. In a letter to Dr. The first such use came in by the United States to control a typhus outbreak in Naples. The chemical was sprayed carelessly throughout the slums without regard to possible side effects for about three million people, as the full extent of its toxicology was not known.
The typhus outbreak was brought under almost immediate control in only three weeks, as 73, people were sprayed per day and 1,, people were treated, demonstrating the awesome power that the new chemical had on infectious diseases. During the s, about twenty years before the introduction of DDT, the Bureau of Chemistry of the Department of Agriculture set standards for residues on food from insecticides. During the s, scientific research, the emergence of other health problems, such as asbestos, and the creation of public interest groups all led to challenges to the use of DDT.
The Public Health Service concluded that if people exposed to abnormal amounts of residues were healthy, then the general public would be too. They also decided that the burden of proof be laid upon those that would ban a chemical and not those who produced it. This meant that they supported placing the burden of proof upon those who produce the chemicals and therefore expose the public to danger.
Unfortunately, the conflict was heavily in favor of the producers, which shows the value of political power and the associated lack of public interest in the issue. Their concern was not as much about the preservation of public health and safety as much as it aimed to help the chemical industry avoid difficulty and therefore receive annual funds.
In , the Department of Agriculture temporarily banned DDT while Congress called for a national embargo on the chemical. Two primary fears that resulted in the stricter regulation of DDT were possible bans on other chemicals and the higher costs of alternatives.
There were also many who did not agree with what Carson had to say about DDT in her book. In , the American Public Health Association reported that, although DDT was still a major threat, the use of the insecticide on cotton fields in Central America was contributing to the resistances to DDT that the mosquitoes began to develop.
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Experimental parasitology. Danboise in preparation of this article. Reader Feedback. Search The Journal. Banned for agricultural uses worldwide by the Stockholm Convention on Persistent Organic Pollutants , the use of DDT is still permitted in small quantities in countries that need it, with support mobilized for the transition to safer and more effective alternatives.
Carson used DDT to tell the broader story of the disastrous consequences of the overuse of insecticides, and raised enough concern from her testimony before Congress to trigger the establishment of the Environmental Protection Agency EPA. Her work attracted outrage from the pesticide industry and others. Following the hearings, President Kennedy convened a committee to review the evidence Carson presented.
The committee's review completely vindicating her findings. One of the new EPA's first acts was to ban DDT, due to both concerns about harm to the environment and the potential for harm to human health. There was also evidence linking DDT with severe declines in bald eagle populations due to thinning eggshells. Since DDT was banned in the U. Recently, Carson's work has again been targeted by conservative groups.
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