gliocladium virens GL-21 (WRC-GL-21) EPA Pesticide Fact Sheet 11/90
EPA Pesticide Fact Sheet
Name of Chemical: Gliocladium virens GL-21
Reason for Issuance: Registration of New Biological Pesticide
Date Issued: November 1990
Fact Sheet Number: 217
- Generic Name: Gliocladium virens GL-21
- Trade Names: WRC-GL-21 and WRC-AP-1
- EPA Shaughnessy Code: 128900-8
- Year of Initial Registration: 1990
- Pesticide Type: Biofungicide
- U.S. and Foreign Producers: W.R. Grace & Co., 7379 Route 32
Columbia, MD 21044
2. USE PATTERNS AND FORMULATIONS
- Application sites: The manufacturing use product (MP) is for use only
in the formulation of fungicides. The end-use product (EP) is for use
in the control of damping-off diseases, particularly those caused by
Pythium and Rhizoctonia, of greenhouse ornamental and food crops.
- Types of formulations: A liquid MP Containing 20% active ingredient
and a granular EP containing 12% active ingredient.
- Types and methods of application: The EP is blended with soil or
soilless plant growing media at least 3 days prior to planting or
incorporated into the media surface in plant beds prior to or at
- Application rate: The EP is applied at the rate of 1 - 1 1/4
ounces/cubic foot of media when blended or at the rate of 3/4 -
1 ounce/square foot of bed surface.
3. SCIENCE FINDINGS
Summary Science Statement:
The toxicological data which were submitted for this active
ingredient included reports of an acute oral toxicity/pathogenicity
study, an acute pulmonary toxicity/pathogenicity study and an acute
intravenous toxicity/pathogenicity study. The studies were performed
using rats. All studies were classified as acceptable. The review of
these studies indicates that the biofungicide is not toxic to, infective
in, or pathogenic to rats by oral or pulmonary routes of exposure and
not infective or pathogenic to rats by intravenous injection. Mycelium
of the fungus was used for the injections and was found to be acutely
toxic and lethal to test animals due to mechanical clogging of
capillaries, however, these mortalities were not considered to be
relevant in this case since injection is not a normal route of exposure
and the product consists of chlamydospores rather than mycelium.
Acute dermal toxicity testing was not required for this biofungicide
based on the facts that the end-use product consists of large pellets,
the label will require that gloves be worn when handling the product and
application will be by soil incorporation. A primary eye irritation
study was not required since protective eye covering must be worn. The
inert materials in the product have been exempted from the requirement
for a tolerance in Section 180.1001 and no indications of toxicity were
reported in workers following 1-2 years of working with the organism.
Although Gliocladium strains are known to produce certain toxins,
data were submitted which showed that only one of the known toxins
(gliotoxin) was produced in detectable amounts. Since gliotoxin is
sensitive to oxidation, the levels that may exist in the product are not
considered to be of toxicological significance since the toxin will be
rapidly degraded. This conclusion is supported by the demonstrated lack
of toxicity in the oral and pulmonary studies conducted on rats.
Data requirements for evaluating adverse effects on birds, wild
mammals, freshwater fish, freshwater aquatic requirement for tests on
aquatic birds was waived because it is not expected that the fungus will
enter the aquatic environment since its only use is as a seed treatment.
Data requirements for evaluating adverse effects on freshwater fish and
invertebrates, estuarine and marine organisms, nontarget plants and
insects and honey bees were waived. The seed treatment use pattern
makes it unlikely that Trichoderma would enter aquatic environments,
contact nontarget plant species or that honey bees or other insects
would be exposed to the organism.
Because only minimal exposure, if any, to nontarget organisms may
occur from the use of this biofungicide as a seed treatment, there is
not expected to be a "may effect" situation with regard to endangered
Data for environmental fate (Tier II) are not required for this
biofungicide because no more than negligible environmental exposure
associated with the seed treatment use is likely and the initial (Tier
I) tests were waived or not required.
Property MP and EP
Physical state powder
Density/bulk density fluffed - 28.8 lbs/cu ft.
packed - 43.6 lbs/cu ft.
Storage stability 184 days at 20 degrees C
Corrosion characteristics N/A
- Acute effects: Data were submitted for acute toxicity/ pathogenicity
as determined in oral, pulmonary and intravenous tests. Data were
classified acceptable. The tests indicated that the product was not
toxic to, infective in or pathogenic to rats.
- Other toxicity information: Information was submitted which
demonstrated that no human or animal pathogens were detected during
the manufacturing process. Information was included on the history of
the production process, a summary of sources of operator exposure and
number of exposure hours for a typical employee. No hypersensitivity
or other toxicological effects attributable to working with the
organism were reported.
Data on the ecological effects of the biofungicide were included only
for an avian oral pathogenicity/toxicity study on bob white quail. The
test organism was practically nontoxic to terrestrial avian species by
ingestion. Data requirements for all other ecological effects testing
were waived based on the nature of the fungus and the facts that it is
unlikely that the organism will enter aquatic environments and minimal
exposure would be likely due to the seed treatment use pattern.
The use of the end-use product will be beneficial in the control of
damping-off and seed rot diseases of seedling plants which may be a
source of economic loss by reducing the stand of plants in the field.
The availability of a biological fungicide would provide a less toxic
alternative to the currently registered chemical seed treatments.
5. TOLERANCE ASSESSMENT
An exemption from the requirement for a tolerance for residues of
Trichoderma harzianum Rifai Strain KRL-AG2 on beans, (green and dry),
cabbage, corn (field and sweet), cotton, cucumbers, peanuts, potatoes,
sorghum, soybeans, sugar beets, and tomatoes when used as a seed
treatment in accordance with good agricultural practices was requested.
Since testing of the biofungicide showed not evidence of effects which
would be of toxicological concern, an exemption will be granted.
6. SUMMARY OF MAJOR DATA GAPS
No data gaps exist for this active ingredient.
7. CONTACT PERSON AT EPA
Susan T. Lewis
Product Manager (21)
Registration Division (H-7505C)
Environmental Protection Agency
401 M St., SW.
Washington, DC 20460
DISCLAIMER: The information presented in this Pesticide Fact Sheet is
for informational purposes only and may not be used to fulfill data
requirements for pesticide registration and reregistration.