The United Nations Environmental Program (UNEP) will allow developing countries whose populations suffer heavily from malaria to continue spraying the controversial insecticide DDT (dichlorodiphenyltrichloroethane) until an effective vaccine is found. UNEP’s decision, which was announced in early May, is seen as acknowledging a need among developing countries to use DDT to fight malaria, while urging rapid development of vaccines for a sustainable long-term strategy.

DDT was instrumental in eliminating malaria in North America and Europe in the mid-twentieth century, but concerns over harmful environmental effects largely ended its use in the 1970s. Among DDT’s most vocal critics is the Worldwide Fund for Nature (WWF), which cites evidence of devastating consequences for wildlife thousands of miles away from where the chemical was used. While studies have suggested DDT may pose threats to human health, including reproductive and neurological damage, a conclusive link has not been established.

Proponents of DDT from both developing and industrialized countries contend that DDT’s protective qualities and low cost outweigh environmental hazards in poor countries.

In Africa, where malaria kills approximately one million people a year, most of them children, the relatively inexpensive DDT remains an attractive option. Malaria is estimated to cost the continent approximately $12 billion each year, a cost that includes lost productivity, school absenteeism and treatment.

The conflict has taken center stage in countries such as Mozambique, where over one third of deaths of children under five are due to malaria. Mozambique’s government claims that donors’ aversion to DDT leads to less effective anti-malarial projects. An agreement between the government and the Global Fund to Fight AIDS, Tuberculosis and Malaria allotted $12 million in 2004 for anti-malarial programs such as insecticide-treated bednets, which successfully protect against the disease. Yet despite these efforts, most Mozambican children still lack access to treated bednets and other means of protection.