27 years have passed since the US banned the use of DDT and the ecological gains are obvious. The rare peregrine falcon was removed from the endangered species list last month, and will soon be joined by the bald eagle
Sheryl Gay Stolberg, New York Times
27 years have passed since the US banned the use of DDT and the ecological gains are obvious. The rare peregrine falcon was removed from the endangered species list last month, and will soon be joined by the bald eagle. Brown pelicans are thriving in Florida, and ospreys have returned to the shores of Long Island. Now the UN is drafting an agreement, which could lead to a worldwide ban on DDT.
The talks, which are supposed to resume on September 6 in Geneva and last until the 11th of the month, arouse the opposition of public health officials. According to them, DDT is necessary to stop the spread of malaria, which causes the death of up to 2.7 million people every year, mainly children in developing countries. "A child dies of malaria every 12 seconds," says Diane Wirth, a malaria expert at the Harvard School of Public Medicine, and chair of the American Association of Tropical Medicine and Hygiene.
Wirat is one of about 370 medical researchers in 57 countries who are calling for the new agreement to allow the spraying of DDT in small quantities inside homes. The scientists claim that the elimination of the use of the cheap and effective pesticide should be done gradually, and only if the Western countries conduct studies on the more expensive alternatives and help finance them.
Most countries no longer use DDT for agricultural purposes, or do not admit it. But according to experts, 23 countries still use it to control malaria. Mainly China and India. Mexico committed to stop spraying in 2007 and the World Bank loaned India 200 million dollars to search for alternatives to the substance.
The DDT dilemma stems from a UN plan to eliminate the use of 12 toxic chemical substances, classified as persistent organic pollutants. They all accumulate in the food chain and can travel thousands of kilometers through air, water and through bird migration.
In her book "Silent Spring" from 1962, marine biologist Rachel Carson documented the toxic effects of DDT. She showed how the red-breasted maggots, which had fed on elm leaves that had been sprayed with the substance, died. Following the book, the Environmental Protection Agency was established in 1970 and two years later the use of DDT was banned in the United States.
The negotiations on the group of polluters should be completed at the end of next year. In the meantime, the experts argue with each other on every issue, starting with the question of whether DDT is harmful to human health (the evidence is inconclusive), and ending with the question of whether the recent increase in malaria rates in Mexico is due to the reduction in the use of the substance or from last year's hurricanes, which caused the environment to breed mosquitoes (it seems that both the answers are correct).
On one side are the World Wildlife Fund and Doctors for Social Responsibility - a group of doctors dealing with environmental health. They cite studies that show that even spraying small amounts of DDT in homes causes the substance to appear in the milk of nursing mothers. The foundation calls for a ban on DDT in 2007. The exact date is disputed.
From the second past there are two organizations of scientists - the Association of Tropical Medicine, and the International Malaria Foundation. The foundation claims that setting a zero hour for the DDT ban imposes an "immoral burden on the poorest countries in the world". Until last week, 137 scientists, including three Nobel laureates, signed the letter.
The debate is ongoing at the same time as the deadly return of malaria in areas where it was previously contained. The World Health Organization estimates that 500-300 million new cases of malaria are added every year. There are drugs to treat the disease, but there are patients who cannot afford to buy them. Also, the resistance of the mosquitoes to the drugs is an aggravating problem. The best preventive measure is therefore to be well protected from mosquito bites.
Some believe that DDT's proven ability to repel mosquitoes makes it a perfect solution. Others, including Dr. Mary Galinsky, founder of the International Malaria Foundation and a molecular biologist, say they are willing to look at other alternatives. Meanwhile, the World Health Organization is formulating a plan to reduce the use of DDT. Even if the plan is interesting, the question is - who will pay?
In Israel, as in most Western countries, the use of DDT has been strictly prohibited since the XNUMXs. However, partial use of DDT continues, explains Dr. Erna Metzner, who coordinates the field of pesticides at the Ministry of the Environment. "Today, DDT can only be used to control sand flies, which are much more difficult to fight than other mosquitoes," she says.
The Anopheles mosquitoes, which transmit the malaria disease, fight with the help of other substances. Malaria is not common in Israel. "We are reluctant to use this preparation, because everyone knows its harmful environmental effects. But we also don't want to go to the other extreme, which would leave people hurt," says Dr. Uri Shalom, head of the pest control division at the Ministry of the Environment.
Israel is not a partner in the international initiative to completely ban the use of DDT until 2007, says Dr. Shalom. But according to him, he intends to completely ban the use of DDT "as soon as an alternative preparation is found".
© Published in "Haaretz" on 02/09/1999
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