Operation Ranch Hand had the planes and men spray the toxic herbicide

Soldier spraying Agent Orange

Agent Orange was sprayed over the southern part of Viet Nam and parts of Laos and Cambodia during the Viet Nam War.  The use of this chemical by the US began in 1961 and lasted until 1971 however, the herbicides and defoliants that were left behind by the US continued to be used by southern Vietnamese forces until 1974.
         

Herbicides were originally developed in the 19^th century to kill weeds and make farming and gardening more efficient, although they were not widely used as it was discovered that these chemicals are toxic.  They were then later tested in military laboratories in England and the U.S. during World War II.  Between that time and its extended use in Viet Nam, Agent Orange was tested in various locations around the world.  In 1961 President Kennedy decided to allow the use of herbicides in the war in Southeast Asia and about a year of testing was carried out over areas in the south of Viet Nam. 

The year 1962 brought Operation: Ranch Hand which took Agent Orange from testing into full time use, this operation focused on using Agent Orange, Agent Blue, and Agent White.  For the first couple of years spraying was relatively light, but towards the end of the war it was stepped up to a larger scale.  Many different means of spraying were used and the area over which the herbicides were dumped increased as time went on. 

Since Agent Orange was being used to strip the land of all vegetation and not just to control weeds, doses 5 to 10 times higher than what was used for American Agriculture was sprayed.  About 13 million gallons of Agent Orange were supplied by several companies to the US military.  The companies that manufactured it include Dow Chemical, Diamond Alkali, Uniroyal Chemical, Thompson Chemical, Hercules, Monsanto, Ansul, and Thompson Hayward.  

A byproduct of the production 2,4,5 T, of one of the components of Agent Orange, was TCDD Dioxin, a highly toxic substance. The US Military requisitioned large quantities of Agent Orange for use in the war. As a result of high demand, the manufacturing process of the herbicides was sped up and temperatures of production of 2,4,5 T was raised, ultimately increasing the overall level of dioxin in each batch.  Even today, traces of Dioxin can still be found in areas of Viet Nam.  For information on Dioxin hot spots, and operation ranch hand please follow the picture links to the side of this page.

Even though herbicides made with 2,4,5 - T was eventually banned in the US because of its' toxicity, AO was still sprayed in Viet Nam.