Dow Chemical, the makers of Tebuthiuron, warns that the herbicide should only be used "carefully and in controlled situations" and that "it can be very risky in situations where terrain has slopes, rainfall is significant, desirable plants are nearby and application is made under less than ideal circumstances." But that is exactly what the U.S. government has pressured Colombia to agree to do.
The warning quoted above, conditions under which Tebuthiuron, marketed under the name Spike 20-P, should not be used, essentially describes the terrain in which coca is grown. American officials have long lobbied for the use of Tebuthiuron because it comes in pellet, rather than spray form, and can be dropped by high-flying planes, thus reducing the risk to pilots, if not to the people on the ground below. But Dow AgroSciences, a subsidiary of Dow Chemical, formerly makers of the defoliant Agent Orange, released a statement saying "Tebuthiuron is not labeled for any use on any crops in Colombia, and it is our desire that the product not be used for coca eradication as well."
But Dow's reluctance matters little. Their patent on the herbicide has run out, allowing other companies to manufacture it.
No one knows what the long-term effects of Tebuthiuron are in groundwater or on farmland, and critics, including Colombia's environmental minister, Eduardo Verano, question whether such risks are worth taking with the lives of his countrymen. "We need to reconsider the benefits of the chemical war" he told the New York Times. "The more you fumigate, the more the farmers plant. If you fumigate one hectare, they'll grow coca on two more. How else do you explain the figures?"
The plan, which was drawn up by the State Department's acting assistant Secretary of State for international narcotics and law enforcement affairs, calls for the Colombian military to drop the defoliant, and then only in the southern, rebel-controlled part of the country. The Colombian military, long acknowledged as one of the world's leading abusers of human rights, and more recently as flouting civilian control by the Colombian government, has been engaged in a 35 year-old conflict with rebel guerrillas in the region. It is a war which they have recently admitted they cannot win.