What is Agent Orange?       Agent Orange was a herbicide, or defoliant, which was used in Vietnam to kill unwanted plant life and to remove leaves from trees which otherwise provided cover for the enemy.  Agent Orange was a mixture of chemicals containing equal amounts of the two active ingredients, 2,4-D and 2,4,5-T.  The name, "Agent Orange," came from the orange stripe on the 55-gallon drums in which it was stored.  Other herbicides, including Agent Purple, Agent White, and Agent Blue, were also used in Vietnam to a much lesser extent.  Republic of Korea forces used small amounts of Agent Orange in 1968-69 in the area from the Civilian Control line to the southern boundary of the Demilitarized Zone.  According to the Department of Defense, only Republic of Korea troops were involved in the actual spraying of Agent Orange in Korea. However, it is possible that some US Military personnel may have been exposed to herbicides in Korea. Agent Orange and other herbicides used in Vietnam were tested or stored elsewhere, including, many military bases in the United States.         When and where was Agent Orange used in Vietnam?     Fifteen different herbicides were shipped to and used in Vietnam between January 1961 and 1971.  Agent Orange accounted for over most of the herbicides sprayed in Vietnam.  Agent Orange was used between January 1965 and April 1970.  Herbicides other than Agent Orange were used in Vietnam prior to 1965, but to a very limited extent.  However, a recent study released in April 2003 found that while relatively small amounts of highly dioxin-contaminated Agents Purple and Pink were sprayed in the early 1960s, these agents might have deposited a relatively large percentage of the total dioxin.  The total area sprayed with herbicides between 1962 and 1965 was small, less than 7 percent of the total acreage sprayed during the Vietnam conflict.  Rapid increases in the annual number of acres sprayed occurred from 1962 to 1967.  The number of acres sprayed reached a maximum in 1967, leveled off slightly in 1968 and 1969, and declined rapidly in 1970 prior to the termination of spraying in 1971.       During this time more than 19 million gallons of herbicides were sprayed over 6 million acres, some of which were sprayed more than once.  More than 3.5 million acres of South Vietnam approximately 8.5 percent of the country were sprayed one or more time. Spraying occurred in all 4 military zones of Vietnam.       In Korea, Agent Orange was used by the Republic of Korea Forces in 1968-69. Use was restricted to a strip of land just south of the demilitarized zone and North of the civilian control line. The strip extended along the line for many kilometers. Department of Defense officials have advised us that US troops did not do the spraying. Heavily sprayed areas included inland forests near the demarcation zone; inland forests at the junction of the borders of Cambodia, Laos, and South Vietnam; inland forests north and northwest of Saigon; mangrove forests on the southernmost peninsula of Vietnam; and mangrove forests along major shipping channels southeast of Saigon.  Crop destruction missions were concentrated in northern and eastern central areas of South Vietnam.