Is DDT Making a Comeback?


Most of us born and raised since the publication of Rachel Carson's Silent Spring have little or no memory of times in the not-so-distant past when DDT was the prime weapon used to combat mosquitoes around the world. Since its ban in the US in 1972, and other countries in the 70s and 80s, the idea of bringing back this chemical, which can be passed along in the food chain and accumulate in animal fat cells, has been unthinkable in much of the developed world. With malaria now back at full strength in the developing world, particularly Africa, humanitarian, public health and even environmental organizations are rethinking the use of DDT, if only in limited circumstances.

In May the U.S. Agency for International Development (USAID) endorsed the use of DDT for indoor antimalarial treatment in the developing world.

The World Health Organization (WHO) is expected to do the same in short order, according to a comprehensive report published in the current issue of the journal Nature Medicine.

The chemical's return is sure to raise some eyebrows, but people on the front lines of the malaria fight generally support the decision.

"It's about 20 years too late, but it's a good thing," said Don Roberts, a professor of tropical public heath at Uniformed Services University of the Health Sciences in Bethesda, Maryland.

"I think it's going to make a huge difference in the health of people at risk of malaria."

Supporters of returning the pesticide to action against mosquitoes ensure skeptics that DDT will not be sprayed widely over crops and human populations, but rather applied only to building walls to create a barrier against disease-carrying insects. They also claim that the chemical's use will be monitored to prevent unauthorized agricultural applications, and to ensure that mosquitoes don't develop resistance too quickly. Environmental groups such as the Sierra Club are even deferring to public health officials' statements that such limited use will provide the most effective defense against malaria.

Considering the dire circumstances in parts of the developing world, we should take advantage of the tools we have to provide some relief. At the same time, we hope that researchers will continue to experiment with non-toxic means of controlling mosquito populations, and make sure that actions taken to prevent malaria don't create longer-term ecological problems that could also prove devastating to impoverished people. :: National Geographic News