State Department report to Congress on effects on human health and safety of
herbicides used in the Colombian aerial spray program, January 23, 2001
Human Health and the Safety of Herbicides
Glyphosate is a non-selective herbicide. It is the active ingredient in
several formulations that are sold under various tradenames throughout the
world. The U.S. Environmental Protection Agency (EPA) reregistered glyphosate as
an active ingredient after review and evaluation of a large number of studies
(more than 200) describing the human health and environmental fate and effects
of glyphosate. Their evaluation determined that the use of glyphosate, as
labeled for use in the U.S.,
is acceptable provided that the regulatory controls required by the EPA - the labeled instructions - - are followed. This September
1993 Reregistration Eligibility Decision (RED) determined the risks only for
glyphosate, and its formulated products. Another reassessment by EPA in 2000 of the available
toxicology studies confirmed glyphosate's acceptability; as a result, additional
uses on food crops were approved.
Formulated pesticide products usually contain chemicals other than the active
ingredients to assure that the active ingredient performs in an effective manner
at the appropriate concentration. The other chemicals in the formulated products
are referred to as inert (other) ingredients, and they function as solvents,
emulsifying agents, thickeners, carriers, or preservatives. The term inert means
only that the ingredient is not performing an active pesticide function.
The EPA has developed several lists of chemicals that are approved for use as
inert (other) ingredients in pesticide products. The inert ingredients approved
for use in pesticide formulations used on food crops and on livestock animals
are set forth in the Code of Federal Regulations (40 C.F.R. § 180.1001 (c), (d),
and (e)). Each formulated product must be registered (or "licensed") with EPA
before being offered for sale and use. As part of the process to obtain this
registration, the formulator must submit a listing of the
chemicals used to make the product and a battery of chemistry and toxicity
studies. EPA will not register a formulated product for use on food crops or
animals unless (1) the active ingredient is registered, (2) all ingredients are
granted tolerances of residues or exemption from the requirement of a tolerance
as set forth in 40 C.F.R.
§ 180.1001(c), (d), and (e), and (3) EPA makes a finding that the use of the
product will not cause an unreasonable adverse effect to humans or the
environment.
Two adjuvants (COSMO FLUX-411F
and COSMO-IN-D), the glyphosate product, and water are mixed together to make
the spray solution. These two adjuvants are proprietary products that increase
the effectiveness of the spray solution. It should be noted that EPA does not
regulate adjuvants, as they are not pesticide products as defined by the Federal
Insecticide, Fungicide, and Rodenticide Act. The seller of these adjuvants
voluntarily provided the mixture ingredient lists with their Chemical Abstract
Service (CAS) numbers for a review by the EPA. The EPA reviewed the lists of
ingredients for the two adjuvants and determined that the ingredients in both
adjuvants are listed in 40 CFR 180.1001. Therefore, both adjuvants are
acceptable for use on food crops when the label instructions are followed.
Coca Aerial Eradication Chemicals
The Government of Colombia (GOC) attacks the coca crop primarily through
aerial spraying using the herbicide glyphosate. The GOC has chosen to attack the coca crop primarily by
spraying herbicides from the air rather than going into the fields and manually
cutting down the crop for
cost, efficiency. and safety reasons. All of these reasons relate to Colombia's coca crop being:
o Enormous (122,500
hectares) and expanding (having tripled in size since
1993);
o Widely dispersed (ranging from southeast to southwest Colombia. and in the
north); and
o Concentrated increasingly in guerrilla-dominated areas.
It would be nearly impossible--tactically and financially--to match the pace and
breadth of expansion by dispatching teams to eradicate the coca fields manually. It
would be equally as difficult to protect these workers, or their security
forces, from the certain and deadly violence that would escalate as they
encountered hostile coca growers, insurgents and paramilitary forces protecting
illicit fields. Herbicide application by airplane is the most cost-effective way
of coping with the magnitude of the problem and ensuring that eradication
operations do not turn violent. Spray programs can more quickly and easily
adjust their operations to mitigate potential violence in the face of a likely
confrontation with hostile growers and their defenders than can eradication
teams on the ground.
We disagree with the perception that GOC uses extremely toxic chemicals in this
operation and believe that switching to "less effective" chemicals would risk
undermining the eradication effort and increasing coca cultivation, a move that
would inevitably cause greater health and environmental damage to Colombia.
Glyphosate is one of the most widely used agricultural herbicides in the world.
It has been tested widely in the United States, Colombia, and elsewhere in the
world. The U.S. Environmental Protection Agency (EPA) approved glyphosate for
general use in 1974 and recertified it in September 1993. It is approved by EPA
for use on cropland on which numerous crops are grown, forests, residential
areas, and around aquatic areas. EPA has also established maximum residue limits
(tolerances) of glyphosate in numerous food crops for human consumption. In the
United States. 15-30 million pounds were used
on 15-25 million acres annually in the 1990s; in 1997, approximately 51 million
pounds were used. Glyphosate has been one of the top five pesticides, including
herbicides, used in the U.S.
Glyphosate is used widely for many legal agricultural purposes in Colombia,
including for weed control in fruit orchards and coffee plantations; for
treating pre-seeded fields of rice, cotton, corn, sorghum, barley, and soybeans;
and as a maturing agent for the production of sugar cane. Only ten percent of
all the glyphosate used in Colombia is for coca eradication. In
EPA's last comprehensive review of scientific studies on glyphosate, it
concluded that proper use of glyphosate will not cause adverse effects in
humans. Based on adequate scientific studies, glyphosate does not cause risks of
concern for birth defects. mutagenic effects, neurotoxic effects, reproductive
problems, or cancer. In June 1991, EPA classified glyphosate as non-carcinogenic
for humans. based on adequate cancer studies.
Human dietary exposures and risks are minimal. Exposure to workers wearing
standard protective equipment is not expected to pose undue risks due to
glyphosate's low acute toxicity; however, splashes of the product can cause
transient irritation to skin and eyes. "Maibach (1986) evaluated [glyphosate]
and commonly used household products (Johnson & Johnson baby shampoo. Ivory
dishwashing detergent. and Pinesol liquid cleaner) for acute irritation,
cumulative irritation, and photoirritation, as well as allergic and
photoallergic activity... The authors concluded that [glyphosate] herbicide and
the baby shampoo had less irritant potential than either the cleaner or
dishwashing detergent. There was no difference between [glyphosate] and the baby
shampoo in terms of irritation potential."1
Glyphosate bonds tightly with the soil before breaking down and is thus unlikely
to leach through the soil to contaminate underground drinking water. It is one
of the herbicides that EPA has approved for controlling weeds in aquatic
environments. "The toxicity of glyphosate has been evaluated in combination with
several surfactants and/or other herbicides in acute studies with rats and
aquatic species. Based on the results of these studies, it is concluded that the
simultaneous exposure of glyphosate and other materials does not produce a
synergistic response."2 Glyphosate is not persistent in soil. It does not build
up after repeated use and it is biologically degraded over time by soil
microbes.
Fields treated
with glyphosate can be replanted immediately.
The coca
spray mixture consists of water, glyphosate and the inert ingredients in the
formulated product. and two other products also approved for use by the
Colombian government--COSMO FLUX-411F
and COSMO-IN-D--to facilitate spraying. The two products are added along with
the glyphosate formulated product and with water to complete the tank mixture
for the spray solution. COSMO FLUX-411F
is a surfactant. It
increases the herbicide penetration through the waxy layer of
the coca leaf by
allowing more of the spray to stick to the plant. When more of the spray
solution sticks to the plant, the herbicide becomes more effective which means
it can be applied in smaller doses. COSMO-IN-D is an anti-foaming additive. It
is used to minimize the foam created by the mixture-circulating pump inside the
aircraft spray hopper. Without
it, a vacuum could occur within the spray pressure pump,
causing the spray system to shut down during flight. Surfactant and anti-foaming
products, such as these, are commonly used in agricultural spray operations
wound the world. COSMO-IN-D and COSMO FLUX-411F are produced in
Colombia
and Colombia's
Ministry of Health has classified them as toxicology Category IV -- lightly
toxic. The EPA has determined that the ingredients in both are listed in 40 C.F.R. § 180.1001, and that
they are acceptable for use on food products when the label instructions are
followed.
1 Williams, C., Kroes, R., and Munro, I.
(2000). Safety Evaluation and Risk Assessment of the Herbicide Roundup and Its
Active Ingredients. Regulatory Toxicology and Pharmacology 31, 117-165 (2000).
2 Ibid.
Attachment:
Williams, C., Kroes, R., and Munro, I. (2000).
Safety Evaluation and Risk Assessment of the Herbicide Roundup and Its Active
Ingredients. Regulatory Toxicology and Pharmacology 31, 117-165 (2000).
This document, a scientific journal article, is available at
http://usfumigation.org/Restricted/Glyphosate&Humans-Monsanto_prop/index.htm