Trichoderma harzianum (T-22G, F-Stop) - EPA Pesticide Fact Sheet 11/90
EPA Pesticide Fact Sheet
- Name of Chemical: Trichoderma harzianum Rifai Strain KRL-AG2
- Reason for Issuance: Registration of New Biological
- Date Issued: November 1990
Fact Sheet Number: 218
- Generic Name: Trichoderma harzianum Rifai Strain KRL-AG2
- Trade Names: F-Stop Biological Fungicide Concentrate and F-Stop
Biological Fungicide Seed Protectant
- EPA Shaughnessy Code: 128903
- Year of Initial Registration: 1990
- Pesticide Type: Biofungicide
- U.S. and Foreign Producers: Eastman Kodak Company, 343 State Street,
Rochester, New York 14650
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 and seed rot diseases caused by Pythium
species on beans (green and dry), cabbage, corn (field and sweet),
cotton, cucumbers, peanuts, potatoes, sorghum, soybeans, sugar beets,
- Types of formulations: Both products are identical and are powdered
formulations containing 98% of the active ingredient. The active
ingredient is a genetically modified strain of Trichoderma harzianum
derived by protoplast fusion of two auxotrophic mutants of
- Types and methods of application: The EP is a seed treatment applied
as a water-based slurry or in combination with diluents, carriers
and/or adjuvants approved for coating seed through standard slurry or
mist type commercial seed treating equipment.
- Application rate: The EP is applied at the rate of 5 ounces of
product per 100 pounds of seed.
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 indicated that the biofungicide is not toxic to, infective
in, or pathogenic to rats by oral, pulmonary or intravenous routes of
A request that acute dermal toxicity testing be waived for this
biofungicide was made based on the fact that the parent organism is wide
spread and innocuous in nature. To support the waiver, additional
information on worker exposure was requested. Information on the history
of the production process, a summary of sources of operator exposure and
the number of exposure hours for a typical employee were submitted. The
major potential source of worker exposure occurred during the
fermentation process. No workers have shown evidence of dermal
sensitivity to the organism and at other steps in the manufacturing
process no indication of adverse effects were shown. Based on this
information and the results of the acute studies, the acute dermal
toxicity testing was waived because there is little likelihood of acute
effects from dermal exposure.
A primary eye irritation study was conducted on rabbits. The
Trichoderma harzianum strain initially caused slight irritation to the
eyes but no irritation was noted at 7 days after treatment. No
incidents of hypersensitivity in humans have occurred during the
development of the products.
The company was also requested to identify any sources of bacterial
contamination and the steps in the manufacturing process where
contamination might occur to ensure the absence of pathogenic
microorganisms and/or toxins. No human or animal pathogens were
detected in any of the production batches of the products.
To support the lack of adverse effects on wildlife, an avian oral
pathogenicity/toxicity study on bob white quail was submitted which
indicated that the test organism is practically nontoxic to terrestrial
avian species by ingestion. The 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
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 no 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.
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.