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One of the most controversial aspects of Plan Colombia is
the requirement for the Colombian Government to carry out fumigation programs
in an effort to eliminate illegal coca cultivations. Along with chemical
herbicides, one of the primary weapons used in these aerial spraying efforts
is the fungal herbicide Fusarium oxysporum. Although Fusarium fumigation
is touted by herbicidal suppliers and the U.S. Department of State as an
economically efficient and environmentally sound method of combating drugs,
the reality of Fusarium usage conflicts sharply with any claims of its
safety and effectiveness. A recent article in the Washington Post describes
massive food crop damage and river poisonings in Colombia's southern department
of Putumayo. The mayor of La Hormiga, a municipality located in the heart
of Putumayo, predicts widespread hunger in the town of 30,000 as a direct
result of spraying. Reports like these are not uncommon or even surprising.
When the history and scientific study of Fusarium fumigation is considered,
the consequences of its mass usage in any environment become quite predictable.
History
The U.S. government first became interested in Fusarium in the 1960s
after the fungus was found to be the causative factor of a blight that
destroyed coca populations in Hawaii. As a response to growing cocaine
use in the U.S., government agencies along with other researchers began
to develop methods of mass production and field application of Fusarium.
Efforts were also made to develop new strains and isolate phytotoxins for
use against other narcotic plants.
In the early 90s, a Fusarium epidemic spread through coca fields of
the Upper Huallaga Valley of Peru. In 1993, during a visit by a U.S. sponsored
human rights delegation to the Huallaga valley, delegates were assailed
with numerous accounts of US DEA planes spraying the fungus over coca fields.
Although it is difficult to prove U.S. involvement with any certainty,
the effects of the Fusarium outbreaks in Peru are clear. As the disease
spread through the valley, the U.S. embassy reported that Fusarium was
not specific to coca and was destroying a wide range of other plant species
including food crops. Moreover, after the initial onslaught of the epidemic,
the fungus appeared to have drastic long-term effects on the soil, making
it difficult to replant crops. As a result, 3,000 peasant families were
forced to find other methods of subsistence. Many farmers were forced
to move deeper into the forest to secure uncontaminated land for crops.
In 1999, Jim McDonough, the new Director of Florida's Office of Drug Control,
lobbied for use of a strain of Fusarium to combat illegal marijuana cultivations.
The idea was rescinded due to various health and environmental concerns
raised by the press, Florida Citizens, and other government agencies, including
the Florida Departments of Environment and Agriculture.
Non-specificity
As was evident during the Huallaga Valley epidemic, Fusarium is not
host specific to coca and is very unstable in the natural environment.
U.S. government studies in Peru showed that the fungus was killing many
other plants including tomato, achiote, and papaya. Further studies by
the International Institute of Biological Control provided similar conclusions
- Fusarium was linked to stress and death of various experimental plant
species. Still, many U.S. scientists maintain that the EN-4 strain currently used in Colombia is specific to plants in the genus Erythroxylum,
which includes coca (not a very reassuring claim considering that over
200 other plant species are included in this genus, many of which are located
in Colombia).šš However, many Colombians have seen the evidence of Fusarium's
non-specificity first-hand. A few years back, a strain of the fungus ravaged
flower growers in the area near Bogota, producing effects similar to those
observed in Peru.
Mutability
Living things are not static entities; Fusarium is not an exception.
One of the persistent fears associated with herbicidal use of this fungus
involves its remarkably high ability to mutate. A good portion of this
mutability can be accounted for by the unusually high number of transposons
embedded in the genome of Fusarium. Transposons are mobile segments of
DNA with the remarkable ability to "jump" between different gene locations.
This relocation of transposons may account for wide variation between generations
and is likely responsible for the tendency of Fusarium to readily adapt to a variety of host species. Indeed, this makes sense
from an evolutionary perspective. A chance mutation that lends a parasitic
organism the ability to exploit a new host organism would be highly adaptive
by eliminating competition and freeing up new resources; therefore, a highly
mutable organism, such as Fusarium, will likely adapt and spread quickly
to new host plants.
Health Threats
Clearly the environmental dangers posed by Fusarium fumigation are worrisome
but the health threats that are linked to the fungus are equally threatening.
Fusarium produces numerous toxins (Fumosin B1, Nivalenol, Fusariotoxin,
etc...) that are associated with fever, nausea, vomiting, and even cancer
in lab animals and humans. A study of immunocompromised patients exposed
to Fusarium revealed a 76% mortality rate. In other words, Fusarium fumigation
wages war not only on coca but on innocent Colombians.
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