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Some Vietnamese children still live with Agent Orange problem

Maika Elan / AP

Chu Thanh Nhan, 12, sits in an empty classroom at a rehabilitation center in Danang, Vietnam. The children were born with physical and mental disabilities that the center's director says were caused by their parents' exposure to the chemical dioxin in the defoliant Agent Orange.

Maika Elan / AP

Dang Cong Chinh, center, plays with other children at a rehabilitation center in Danang, Vietnam.

Maika Elan / AP

Le Trung Hong Phuc, 9, plays with colored blocks at a rehabilitation center in Danang, Vietnam.

The U.S. for the first time will begin cleaning up leftover dioxin that was stored at the former military base that's now part of Danang's airport in central VietnamDioxin, which has been linked to cancer, birth defects and other disabilities, is the dangerous chemical left from the defoliant Agent Orange.

The U.S. military dumped some 20 million gallons of Agent Orange and other herbicides on about a quarter of former South Vietnam between 1962 and 1971, decimating about 5 million acres of forest.

The Agent Orange issue has continued to blight the U.S.-Vietnam relationship because dioxin can linger in the environment for decades, entering the food supply through the fat of fish and other animals. -- The Associated Press contributed to this blog post.

Keystone / Getty Images

Communist troops captured Saigon on April 30, 1975, ending one of the most bitter conflicts ever to involve the United States.

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