Between 1961 and 1971, the U.S. sprayed 20 million gallons of an herbicide known as Agent Orange over Vietnam. The purpose was to decimate the canopy of the native jungle and gain a military advantage over the Vietcong in the Vietnam War. After half a century, the consequences of this chemical war are still palpable to the Vietnamese. According to Red Cross estimates more than 3 million people have been affected by the chemical Dioxin present in Agent Orange.

“It was only after independence that we heard about Agent Orange,” recalls Tran Quoc Viet, a war photographer, “and learned how scary its effect was.” At the time, the pollutant contaminated water and food sources, and it is estimated that at least 150.000 children were born with severe congenital disabilities afterward. Thousands of U.S. veterans who came into contact with it during the war were also poisoned, along with children born to them after it ended. “It enters your bloodstream and then your DNA,” says UC Davis Professor Emeritus Larry Berman. “And it lives there as a time bomb.”

In Toxic – U.S. Warfare in Vietnam, Big Story correspondent Jason Motlaugh hears directly from the survivors of a conflict that ended in 1975 but is still claiming victims to this day.