Agent Orange in Vietnam: A toxic legacy

Agent Orange is an herbicide that contains dioxin, a highly toxic compound linked to serious birth defects and health problems.

Vietnamese officials say more than 4 million Vietnamese citizens are suffering health problems related to Agent Orange.

The United States says the actual number of Agent Orange victims is lower and that further scientific study is needed to determine the link between Agent Orange and health.

U.S. forces sprayed more than 20 million gallons of Agent Orange and other herbicides on southern and central Vietnam from 1961 to 1971 to kill crops and strip Vietnamese guerrillas of ground cover.

Dioxin attaches itself to dirt and sediment and stays for generations.

Vietnam has identified three Agent Orange "hot spots" in need of immediate cleanup at former U.S. air bases in Danang, Bien Hoa and Phu Cat.