Clean Up Efforts


Click on the image to launch a Google Earth interactive display of known and potential dioxin “hot spots” in Vietnam from the use of toxic herbicides. Created by the War Legacies Project,  the map is based on research conducted by Hatfield Consultants and their Vietnamese counterparts at the 10-80 Committee. Their research was funded by the Ford Foundation through a grant to the Ministry of Health in 2002. (Also available for Google Maps)

Agent Orange/dioxin residues in Vietnam can be and are being cleaned up, using well-known and cost-effective methods. Additional resources would allow scale-up and expansion of these best practices to all existing “hot spots.” Dioxin-contaminated herbicides were sprayed over about 5 million acres of upland and mangrove forests and about 500,000 acres of crops — a total area the size of Massachusetts, about 24 percent of southern Vietnam. Some areas of Laos and Cambodia along the Vietnam border were also sprayed. Dioxin is not water-soluble. It breaks down in sunlight or clings to soil particles and is washed away in rainwater, so little remains in areas that were sprayed by air.[i] However, Hatfield Consultants (Canada) has found “hot spots” of high dioxin concentrations in areas where the dioxin-contaminated herbicides were stored, leaked or spilled. These are mostly on and around former U.S. military installations. Dioxin leached into the soil or was transported by runoff into the sediments of nearby rivers, lakes and ponds.

About Hot Spots: Research continues, but as of August 2011, Hatfield and Vietnamese officials had located 28 dioxin hot spots, primarily where the Ranch Hand program was based. The most significant are at the Da Nang, Phu Cat and Bien Hoa airports that were used by the U.S. military.[ii] Safety standards for dioxin vary from country to country and by substance tested: food, air, water or soil. As most exposure to dioxin is through the food chain, the greatest concern for human exposure is the dioxin level in soil and sediment.

  • The general standard in most countries is that dioxin levels must not exceed 1,000 ppt (parts per trillion) TEQ (toxic equivalent) in soil and 100 ppt in sediments. Levels beyond that require immediate remediation. Average dioxin contamination in the soil of industrialized nations is less than 12 ppt.
  • In Vietnam, researchers found dioxin levels of up to 365,000 ppt at Da Nang, 262,000 ppt on the Bien Hoa base and 236,000 ppt in former storage areas on the Phu Cat base.[iii]

Hot Spots Cleanup: The U.S. Agency for Toxic Substance and Disease Registry has determined that dioxin levels higher than 1,000 ppt in soil require intervention, including surveillance, research, health studies, community and physician education, and exposure investigation.[iv] The first step is to prevent access to contaminated areas by constructing fences and other barriers to protect the local population from further exposure. Second, containment measures such as concrete caps, filtration systems and sediment traps can prevent dioxin from being transported to secondary sites such as ponds and streams, and from there up the food chain to people. Then the isolated soils can be cleaned of dioxin through appropriate technical means. 

Dioxin cleanup: The cost of cleanup depends on the severity of the contamination, the type of soil affected and later uses planned for the area. Hatfield Consultants and its Vietnamese counterpart,

Office of National Steering Committee 33, estimate that a total of 234,780 cubic meters of soil and sediment need remediation at Bien Hoa, Da Nang and Phu Cat, the worst known sites – enough material to cover a football field nine feet deep. In mid-2010, the UNDP/Global Environmental Fund estimated the remediation cost for all three sites at $58.7 million.[v]  In mid-2011 the cost to clean up the dioxin at the Da Nang airport increased from an earlier estimate of $34 million to $43 million, bringing the total estimated costs for the three dioxin hotspots to $67.7 million.

Actions by Vietnam and the United States: In 2003, the U.S. Environmental Protection Agency began a $2.4 million project in cooperation with the Vietnamese to investigate the situation at Da Nang, funding U.S. government agencies and their contractors. In 2007, the Joint Advisory Committee of U.S. and Vietnamese agencies began holding yearly meetings. In the same year, Congress allocated $3 million to address remediation of dioxin hotspots in Vietnam and to support public health programs in the surrounding communities.[vi] A second allocation of $3 million was included in the FY2009 Foreign Operations spending bill, and a third allocation of $15 million, substantially increasing U.S. government support, was approved for FY2010. In April 2011, Congress approved $18.5 million for FY2011, of which $3 million was specifically reserved for health activities.  The U.S. Agency for International Development (USAID) has disbursed $3 million from Congressional appropriations in 2007, 2009 and 2010 to three non-governmental organizations for programs to support those with disabilities in the Da Nang area over the period 2008-2011. USAID is expected to increase that level to $3 million/year from 2012.  In October 2009, USAID allocated $1.69 million to a U.S. engineering firm to assess dioxin contamination there and design a remediation plan. In October 2010, Secretary of State Hillary Clinton announced U.S. government support for a project to clean up the Da Nang hot spot which is now costed at $43 million.[vii]

NGO Activities: The lead NGO has been the Ford Foundation, which through April 2011 provided $17.1 million in grants in Vietnam to test for and contain dioxin-contaminated soils, develop treatments and support centers for Vietnamese who have been exposed, restore landscapes, and educate the U.S. public and policymakers.  Ford has also worked to increase awareness about Agent Orange/dioxin among donors and to encourage new donors such as UNICEF, UNDP, The Atlantic Philanthropies and the Bill & Melinda Gates Foundation. In May 2011 the Ford initiative on Agent Orange transited to the Aspen Institute. Many U.S. and Vietnamese NGOs have projects that provide services to the disabled in Vietnam.

For More Information Contact: Janice Joseph at the Aspen Institute Agent Orange in Vietnam Program, 477 Madison Avenue Suite 730 New York, NY 10022., 212 895-8000

August 2011 


[i] Dwernychuk, Wayne et al. “The Agent Orange Dioxin Issue in Vietnam: A Manageable Problem.” Paper Presented at Dioxin 2006, Oslo, Norway

[ii] Vo Quy, “Statement to the House Subcommittee on Asia, the Pacific and Global Environment,” Washington DC, June 4, 2009,

[iii] Committee 33 PowerPoint Presentation: “Overcoming consequences of toxic chemicals/dioxin: A difficult and long-term task.” April 2009 and Office of the National Steering Committee 33, Ministry of Natural Resources & the Environment, and Hatfield Consultants, “Environmental and Human Health Assessment of Dioxin Contamination at Bien Hoa Airbase, Vietnam,” July 2011.

[iv] Hatfield Consultants “Summary of Dioxin Contamination at Bien Hoa, Phu Cat and Da Nang Airbases, Viet Nam.” PowerPoint presentation for the meeting of the U.S.-Vietnam Dialogue Group On Agent Orange/Dioxin, Washington, DC June 2009. .

[v] Committee 33 PowerPoint Presentation: “Overcoming…

[vi] Michael Martin, “Vietnamese Victims of Agent Orange and U.S.-Vietnam Relations” Congressional Research Service Report. (May 2009) p. 9

[vii] $500,000 is being used to finance a staff person for dioxin issues at the U.S. embassy in Hanoi and for more expert exchanges.