Definition
ChEBI: A member of the class of thiadiazoles that is 1,2,4-thiadiazole which is substituted at positions 3 and 5 by trichloromethyl and ethoxy groups, respectively. A fungicide, it has been used particularly for the control of Phytophthora and
Agricultural Uses
Fungicide: Etridiazole is a fungicide used in some countries
as a seed treatment on barley, beans, corn, cotton, peanuts,
peas, sorghum, soybeans, safflower, and wheat. It is
also used on cotton for in-furrow application at planting,
on ornamental plants and shrubs by horticultural nurseries,
on non-bearing citrus and non-bearing coffee, and
for golf course fairways, tees and greens. Some states
hold Special Local Need registrations for use on tobacco
transplants.
Trade name
AATERRA®; BANROT® (With
Thiophanate-methyl); DWELL®[C]; ETHAZOLE®;
4-WAY®; KOBAN®; MF-344®; OLIN MATHIESON®
2,424; OM® 2424; PANSOIL®; TERRACHLOR-SUPER X® (with Pentachloronitrobenzene); TERRACLOR SUPER
X® (with Pentachloronitrobenzene); TERRACOAT®;
TERRAFLO®; TERRAMASTER®; TRUBAN®
Potential Exposure
Aromatic hydrocarbon; Thiazole fungicide Etridiazole is a fungicide used in some countries as
a seed treatment on barley, beans, corn, cotton, peanuts,
peas, sorghum, soybeans, safflower, and wheat. It is
also used on cotton for in-furrow application at planting, on
ornamental plants and shrubs by horticultural nurseries, on
nonbearing citrus and nonbearing coffee, and for golf
course fairways, tees and greens. Some states hold Special
Local Need registrations for use on tobacco transplants
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions) if
breathing has stopped, and CPR if heart action has stopped.
Transfer promptly to a medical facility. When this chemical
has been swallowed, get medical attention. Give large
quantities of water and induce vomiting. Do not make an
unconscious person vomit. Do not induce vomiting when
formulations containing petroleum solvents are ingested
Shipping
UN2810 Toxic liquids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical
Name Required. Military driver shall be given full and
complete information regarding shipment and conditions in
case of emergency. AR 50-6 deals specifically with the
shipment of chemical agents. Shipments of agent will be
escorted in accordance with AR 740-32.
Incompatibilities
Diazo compounds can detonate. This
applies in particular to organic azides that have been sensitized by the addition of metal salts or strong acids. Toxic
gases are formed by mixing materials of this class with
acids, aldehydes, amides, carbamates, cyanides, inorganic
fluorides, halogenated organics, isocyanates, ketones,
metals, nitrides, peroxides, phenols, epoxides, acyl halides,
and strong oxidizing or reducing agents. Flammable gases
are formed by mixing materials in this group with alkali
metals. Explosive combination can occur with strong oxidizing agents, metal salts, peroxides, and sulfides. This
chemical is sensitive to prolonged exposure to heat. This
chemical is incompatible with strong oxidizing agents
Description
Etridiazole (20) was first described in 1969 and is a
contact fungicide for control of soilborne diseases caused
by Pythium and Phytophthora. Formulated as a WP
(Terrazole), etridiazole may be used in a preventive
program for control of Pythium blight in turf and of
damping-off in ornamentals. It is also formulated in
mixture with pentachloronitrobenzene (quintozene) as
Terraclor Super X, which is applied in-furrow to cotton
for control of seedling diseases (Rhizoctonia, Pythium,
Fusarium). Application rates in cotton are equivalent to 1
to 1.5 and 0.26 to 0.39 kg ai ha?1 for PCNB and etridiazole,
respectively.
Waste Disposal
Incineration would be an
effective disposal procedure where permitted. If an efficient
incinerator is not available, the product should be mixed
with large amounts of combustible material and contact
with the smoke should be avoided. In accordance with
40CFR165, follow recommendations for the disposal of
pesticides and pesticide containers
Uses
5-Ethoxy-3-(trichloromethyl)-1,2,4-thiadiazole is a fungicide that can be incorporated into the soil or compost to control Phytophthora spp. and Pythium spp. Useful in cannabis testing kits as a component of pesticide mixes (P698235).
Uses
Etridiazole is a contact fungicide with protective and curative
action that is used to control Phytophthora and Pythium spp. in ornamentals,
cotton, peanuts, vegetables and turf.
Production Methods
The commercial production of etridiazole involves synthesising the compound through a multi-step process starting with a chlorinated thiadiazole precursor. The key intermediate is typically 5-ethoxy-3-(trichloromethyl)-1,2,4-thiadiazole, which is formed by chlorinating and ethoxylating a thiadiazole ring system. This reaction introduces the trichloromethyl and ethoxy functional groups that are essential for the fungicidal activity of etridiazole. The synthesis is carried out under controlled conditions to ensure purity and minimize environmental hazards.
Mechanism of action
Contact with protective and curative action. Lipid peroxidation inhibitor.
Metabolic pathway
The main metabolic pathways of etridiazole in mammals are dechlorination
of the 3-trichloromethyl moiety followed by oxidation yielding
the carboxylic acid derivative or glutathione-mediated dechlorination.
Catabolism of the glutathione conjugate via the mercapturic acid pathway
affords the cysteine conjugate that is in turn N-acetylated to give the
mercapturic acid.
Degradation
The DT50 for hydrolysis of etridiazole is 103 days (25 °C, pH 6). The compound
was hardly decomposed at 20 °C by sunlight over 7 days (PM).
The rate of hydrolysis of etridiazole increased with pH and temperature
and the only product was 3-carboxy-5-ethoxy-1,2,4-thiadiazole (2) (EPA,
1980).
Toxicity evaluation
Etridiazole has low acute toxicity toward mammals
(rat: oral LD50 1,100 mg/kg; rabbit: dermal LD50 >
5,000 mg/kg; rat: inhalation LC50 (4 h) 5.7 mg/L), and
birds (mallard duck: LC50 1,650 mg/kg; bobwhite quail:
LC50 > 5,000 mg/kg). It is also nonteratogenic. However,
chronic administration to rats was associated with an
increased incidence of thyroid follicular cell tumors, and
etridiazole (Terrazole) is included by the EPA in its list of
Group B2 carcinogens.
The only noteworthy ecotoxicological effect concerns
the aquatic toxicity of the combination product, Terraclor
Super X, which is highly toxic towards both fish and
Daphnia. However, this can be attributed more to the
PCNB component (bluegill sunfish: LC50 0.1 mg/L, EPA
designation “highly toxic”) than to etridiazole (LC50
3.27 mg/L, “moderately toxic”). Risk in practice would be mitigated by the use pattern of the product involving
in-furrow soil application.
