Report
on Issues Related to the Aerial Eradication of Illicit Coca in Colombia
Released by the Bureau for
International Narcotics and Law Enforcement Affairs. September 2002
Department
of State’s Comments on EPA August 19, 2002 Letter
The Department wishes to respond to three concerns
raised by the EPA in its August 19 response to Secretary Powell. First, EPA
expressed concern about the level of eye toxicity of the glyphosate formulated
product which the Department has been using in the aerial spray program in
Colombia (e.g., EPA Response at pp. 2, 33). Secondly, EPA replied that
it could not evaluate the toxicity of the tank mixture (glyphosate formulation,
water, surfactant) as sprayed in Colombia because the Department did not supply
toxicity tests on that mixture (e.g., EPA Response at pp. 2, 33). These
two concerns prompted EPA to recommend "that DOS consider using an
alternative glyphosate product (with lower potential for acute toxicity) in
future coca and/or poppy aerial eradication programs." (EPA Response at p.
12) Finally, EPA raised questions regarding the potential for spray drift to
legitimate crops from aerial eradication (e.g., EPA Response at p. 59).
Glyphosate formulation:
As this report was being prepared, the Department has
worked with its supplier of glyphosate to identify a slightly different
formulation that is less of an eye irritant because it uses a different inert
surfactant. This formulation is also known to have as low or lower toxicity
ratings in all other categories as well. Although this alternative formulation
has only recently been registered in Colombia, it has been extensively tested
and widely used elsewhere, including the U.S., and is registered for
non-agricultural use in the U.S. by the EPA.
This alternative formulation addresses EPA’s concern
in its response to the Department of State. The Department plans to switch to
this alternative formulation for use in the aerial spray program in Colombia as
soon as the alternative formulation can be manufactured, purchased, and
delivered.
Toxicity tests:
EPA indicated that it could not verify the potential
toxicity of the spray mixture: the glyphosate formulation diluted with water
and fortified with additional surfactant. The Department has commissioned
toxicity tests of the spray mixture being used in Colombia. The most relevant
portion of the studies has been completed; it confirms that the risk of eye
irritation is low to persons not handling or mixing the concentrated glyphosate
formulation. The Department also expects the full tests to demonstrate that
this mixture poses no health risk for humans. The EPA-certified laboratory that
is performing the studies is doing so in a professional, scientific manner,
which has required a considerable amount of time. The results will be forwarded
to the Committees, and to the EPA, as soon as the Department receives final
copies of the studies.
The Department has also commissioned toxicity tests
for the spray mixture using the alternative glyphosate formulation discussed above.
These will be performed as soon as that formulation is available for mixing in
field conditions.
Spray drift:
The EPA used a computer model
to indicate a possibility that non-target plants hundreds of feet away might be
exposed to a fraction of the glyphosate application, depending on spray droplet
size and wind conditions. USDA scientists and the Colombian Environmental
Auditor to the spray program regularly look for evidence of spray drift as part
of ground truth verification missions. These experts, who actually go to the
fields, have concluded consistently that evidence of spray drift is rare.
Post-spray field visits indicate that if this drift occurs, it is most often in
trace amounts that have no observable adverse consequences on non-target
plants.