Between 1962 and 1971, approximately 20,000,000 gallons of chemical herbicides and defoliants were sprayed on South East Asia, predominately Vietnam.
Agent Orange is the code name for one of the herbicides and defoliants used as part of the herbicidal warfare program known as Operation Ranch Hand.
"The goal was to defoliate forested and rural land, depriving the Viet Cong and North Vietnamese Army of cover; another goal was to induce forced draft urbanization, destroying the ability of small farmers to support themselves in the countryside, and forcing them to flee to the cities, thus depriving the north of their rural support base and food supply."
During the Vietnam War, the Da Nang Air Base (south central coast of Vietnam) was a major U.S military base. Agent Orange, and other herbicides were stored and loaded onto airplanes there, as well as at almost 30 other military bases in Vietnam.
Some agencies still report high levels of dioxin in the soil at these former bases, decades later.
The Da Nang Air base is still operational; it's now an International Airport.
I met Mr. R. recently, a 57 year old Vietnam veteran.
He was an airplane mechanic and stationed at Da Nang Air Base, from September 1972, until the US flag was lowered on March 20th, 1973.
He has recently completed treatment for Non-Hodgkins Lymphoma. His treatment was complicated by a stroke and he remains paralyzed on the left side of his body.
Before he got sick he was a welder and a volunteer football and baseball coach for a local high school.
A good site to review on Agent Orange is:
Non-Hodgkins Lymphoma has been linked to Agent Orange exposure.