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Page 5

Expected ecological effects of herbicide spray campaigns in Colombia

Many individuals and institutions have expressed concern about damage to ecosystems resulting from the spray campaigns. For example, in 2001, a report from Colombia's Comptroller-General's office reported that the spray campaigns were damaging the environment and failing to curb drug production. The report stated that "the majority of the environmental damages are irreversible," and called for a halt to spraying until scientists were able to study the herbicide's environmental effects. 46

Also in 2001, the IX General Assembly of Ecofondo-a consortium of over 200 Colombian environmental organizations including both NGOs and some regional governmental bodies- approved a statement rejecting Plan Colombia and saying that it "seriously affects biodiversity and strategic regional and national ecosystems." 47 The World Wildlife Fund (WWF) has expressed concern about the environmental effects of the spraying through letters to members of the U.S. Congress and to U.S. newspapers. Earthjustice, a U.S.-based non-governmental organization, has submitted a statement to the UN Commission on Human Rights arguing that the spraying has violated human rights through its human health and environmental impacts. 48

These and other expressions of concern about environmental effects of the spray campaigns are well founded. By definition, broad-spectrum herbicides kill a wide range of plants; thus they may destroy rare plant species and disrupt habitats. In addition, the herbicides being sprayed in Colombia may exert toxic effects on wildlife directly. All the concerns about possible adverse ecological effects of the spray campaigns are compounded by the lack of basic information on characteristics of the spray formulations and the concentrations in which they are being applied, as well as the lack of any monitoring system to detect damage if it occurs.

Biodiversity and ecosystem complexity

The areas targeted by spray campaigns in Colombia are characterized by delicate ecosystems and populated by rare and endangered species. The World Wildlife Fund (WWF) notes that "Colombia is among the richest countries for plants and animals on the planet and has been a WWF priority for more than 20 years." 49 Many plant, bird, and other species are endemic to these areas, so the destruction of their habitats could well mean their extinction. According to the website of the Colombian Ministry of the Environment, Colombia is home to 55,000 plant species, of which 1/3 are endemic, making Colombia the country with the second highest number of plants in the world; Colombia is also home to the greatest number of bird species in the world, with 60% of the bird species in South America and 19% of the bird species found worldwide. 50

As discussed above, the herbicide concentrations and rate of application used in Colombia appear to be inconsistent with the label instructions for herbicide application in the US. As the World Wildlife Fund has pointed out, U.S. EPA's evaluations of pesticides' environmental effects "are valid only when there is adherence to the formulation, application, storage, disposal, worker safety and general safety precaution requirements specified by the manufacturer." Even if existing application guidelines are followed, they may be inappropriate for Colombia. WWF notes that EPA's evaluation of glyphosate's environmental effects is based on "the typical usage patterns for which the product will be applied in the U.S.," and that EPA has not evaluated application of glyphosate in tropical forest ecosystems. 51

The very complexity of ecosystems in southern Colombia may make them particularly vulnerable to disruption. American Birds Conservancy (ABC) staff scientist Linda Farley argues that due to the complexity of the ecosystems affected by the spray campaigns, herbicide damage may be more severe than the damage that would result from similar herbicide applications in the temperate ecosystems where application protocols have been designed and tested. According to Farley, the complexity of tropical ecosystems increases the likelihood that damage to one organism will translate into damage to others. 52 Interdependent and coevolved relationships that could be affected by spraying include "pollination systems, insect and plant mutualisms and host-plant interactions, [and] vertebrate habitat requirements."

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46 Michael Easterbrook, "Government Study Raises Doubts on Drugs," Associated Press (September 2, 2001).

47 IX General Assembly of Ecofondo, "Un Pronunciamiento Frente a la Paz y el Plan Colombia" (Bogotá, April 28-29, 2001), available from Ecofondo at

48 Earthjustice and Amazon Alliance, "Spraying Toxic Herbicides on Rural Colombian and Ecuadorian Communities," Written Statement of Earthjustice and Amazon Alliance for Agenda Item 10: Economic, Social, and Cultural Rights, United Nations Commission on Human Rights, 58th Session, March 18-April 26, 2002. Available at, visited February 10, 2002.)

49 Kathryn S. Fuller, President, World Wildlife Fund, "Fumigation Dangers," Chicago Tribune July 23, 2001.

50 Colombian Ministry of the Environment web page:, visited March 1, 2002.

51 William Eichbaum (Vice-President, Endangered Spaces Program, World Wildlife Fund), letter to Senator Russ Feingold, November 21, 2001.

52 Linda Farley, Pesticides and Birds Campaign, American Bird Conservancy, "The Environmental Effects of Glyphosate, "Roundup" on Colombian Ecosystems," (November 20, 2000), available at (visited November 7, 2001).