San Diego

Researchers from the United States and Vietnam met this week in Hawaii to finalize field-testing methods for the nations' first bilateral research project on dioxin pollution from the defoliant Agent Orange.

The scientists plan to begin sampling soil throughout Vietnam this winter to create a database for research on the health and environmental impacts of dioxins spread by the US military during the Vietnam War.

Deadly action: spraying with Agent Orange some 30 years ago left many 'hot spots' of pollution. Credit: AP

“This research programme can be a benefit to the whole world,” says Christopher Portier, director of environmental toxicology at the US National Institute of Environmental Health Sciences (NIEHS), which is planning the project. “But it first must be beneficial to the Vietnamese.”

An international conference on dioxin and other herbicides is set to take place in Hanoi in March. Preliminary results from initial testing may be available for that meeting, officials say.

More than 30 years ago, the US military used Agent Orange as a defoliant on vast stretches of Vietnamese jungle. Aeroplane spraying, along with dioxin dumping and storage facilities, left many 'hot spots' where chemical pollution is thought to be extensive.

Individual researchers from the United States, Canada and other countries have found that dioxin residue has polluted food supplies, including fish. Subsequent studies have shown that those eating the fish have high levels of dioxins, which can cause cancer, immune disorders and birth defects.

During the past two years, the NIEHS and the US Environmental Protection Agency have worked to develop a $400,000 research project designed to provide a comprehensive overview of dioxin in Vietnam (see Nature 406, 818; 2000).