A girl smiles for a photograph at a center for children who have been affected by dioxin exposure in the village of Hoa Nhon, near Da Nang, Vietnam. The Da Nang Association of Victims of Agent Orange/Dioxin says that more than 1,400 children around the city suffer from mental and physical disabilities because of dioxin exposure, a legacy of the U.S. military's use of Agent Orange and other herbicides during the Vietnam War more than 40 years ago. About 60 children attend the Hoa Nhon center each day. Many of them have mental disabilities. Children learn to read and write, sew clothes, make handicrafts and help their families raise crops and livestock. May 29, 2012.