cyanazine (Bladex) Herbicide Profile 12/84
CHEMICAL FACT SHEET FOR:
FACT SHEET NUMBER: 41
DATE ISSUED: DECEMBER 31, 1984
1. DESCRIPTION OF CHEMICAL
- Generic Name: cyanazine
- Common Name: cyanazine (WSSA, BSI, ISO); SD 15418 and WL 19805
- Trade Names: BLADEX 80 WP or 80W, BLADEX 4-WDS or 4L, BLADEX 15G
- EPA Shaughnessy Code: 100101
- Chemical Abstracts Service (CAS) Number: 21725-46-2
- Year of Initial Registration: 1971
- Pesticide Type: Herbicide
- Chemical Family: Triazine
- U.S. and Foreign Producers: Shell Chemicals (U.S.A.)
2. USE PATTERNS AND FORMULATIONS
- Application sites: To control annual grasses and broadleaf weeds in
corn, grain sorghum, cotton, and wheat fallow. Application for
soybean use is pending.
- Types of formulations: Wettable powder, flowable suspension, granular
- Types and methods of application: Aerial and ground sprays,
application through irrigation systems.
- Application rates:
- 1.25-4.75 lbs. a.i./A for corn, preemergence
- 1.2-2.0 lbs. a.i./A for corn, postemergence
- 0.5-1.3 lbs. a.i./A for cotton, preemergence
- 0.6-1.0 lbs. a.i./A for cotton, early postemergence directed
- 0.8-1.6 lbs. a.i./A for cotton, postemergence layby
- 1.0-1.6 lbs. a.i./A for grain sorghum, tank mixed with propachlor
- 0.8-1.2 lbs. a.i./A for grain sorghum, tank mixed with propazine
- Usual carriers: Water or liquid fertilizers for preemergent use on
corn. Water only on postemergence treatments, grain sorghum, and
3. SCIENCE FINDINGS
- Physical state: crystalline
- Color: white
- Odor: none
- Vapor pressure: 1.6 x 10(-9) mm Hg at 20 degrees C
- Melting point: 166.5 - 167 degrees C
- Flammability: non-flammable
- Octanol/water partition coefficient: not available
- Stability: Stable at pH values of 5, 7, and 9 for >30 days. Stable
in sunlight, and at 75 for 100 hours.
- Solubility: Water (23 degrees C) - 160 ppm, benzene (20 degrees C) -
1.5%, xylene - <10%, ethanol (20 degrees C) - 4.5%, chlorobenzene -
<10%, chloroform - 21.0%, methylcyclohexanone - 21.0%
- Unusual handling characteristics: none reported
- Acute effects
- Acute oral LD50 - 334 mg/kg (male rats), 156 mg/kg (female rats)
- Acute dermal LD50 - >2,000 mg/kg (rabbits) (Category III)
- Acute inhalation toxicity - LC50 >2.28 mg/kg (Category III)
- Primary eye irritation - mild eye irritation (Category II)
- Major routes of exposure: dermal, inhalation
- Chronic effects
- Oncogenicity: results inconclusive
- Teratology: F-344 rats - increased incidence of anophthalmia and
microphthalmia at 25 mg/kg/day, NOEL = 10 mg/kg/day. Increased
incidence of diaphragmatic hernia in all treated groups. More
data are required to ascertain the nature of this effect.
Sprague-Dawley rats - slight decrease in maternal body weight at
30 mg/kg/day. NOEL = 3 mg/kg/day. Rabbits - maternal toxicity
and fetotoxicity at 2 mg/kg/day. NOEL = 1 mg/kg/day.
- Mutagenicity: data gap
- Immunotoxicity: data gap
Physiological and Biochemical Behavioral Characteristics
- Translocation: When applied to soil, cyanazine is absorbed by the
roots and translocated to the leaves.
- Absorption and leaching characteristics: Cyanazine is reversibly
adsorbed to soil particles. The degree of adsorption varies with
soil texture, water content, and organic matter content. Leaching
rate into the soil was measured on a sandy loam soil and found to
be comparable to that of atrazine.
- Microbial breakdown: Cyanazine is degraded in the soil primarily
- Loss from photodegradation and/or volatilization: Under field
conditions there is only a minimal loss of cyanazine by either
photodecomposition or volatilization.
- Resultant average persistence: Half-life about 2 weeks under
conditions favorable for plant growth.
- Half-life in water: unknown.
- Hazards to birds: Data are incomplete. Preliminary data show low
toxicity, suggesting minimal hazards.
- Hazards to fish and aquatic invertebrates: Data are incomplete.
Preliminary data show low toxicity, suggesting minimal hazards.
- Potential problems with endangered species: No hazards indicated.
- List of crops and tolerances (CFR 180.307): corn, fodder - 0.2 ppm;
corn, forage - 0.2 ppm; corn, fresh (Inc. sweet)(K+CWHR) - 0.05 ppm;
corn, grain - 0.05 ppm; cotton, seed - 0.05 ppm; sorghum, forage -
0.05 ppm; sorghum, fodder - 0.05 ppm; sorghum, grain - 0.05 ppm;
wheat, forage, green - 0.1 ppm; wheat, grain - 0.1 ppm; wheat,
straw - 0.1 ppm.
- List of food contact uses: corn, cotton (oil), sorghum, wheat.
- Results of tolerance assessment: No ADI can be set at this time.
4. SUMMARY OF REGULATORY POSITION AND RATIONALE
- Use classification: Reclassified (by the Registration Standard) as a
Restricted Use chemical because of teratogenic effects, and because
it is found in groundwater.
- Use, formulation, or geographic restrictions: Manufacturing-use
products may only be formulated into end-use products intended for
use as a herbicide on corn, cotton, sorghum, or fallow land, or
- Unique label warning statements:
- Use classification statements: Labels of all formulated products
must bear the following statements:
- RESTRICTED USE PESTICIDE: Because cyanazine can leach into
groundwater, and has produced birth defects in laboratory animals,
this product may be applied only by certified applicators or
persons under their direct supervision.; and
- Cyanazine is a pesticide which can travel (seep or leach) through
soil and can contaminate groundwater which may be used as drinking
water. Cyanazine has been found in groundwater as a result of
agricultural use. Users are advised not to apply cyanazine where
the water table (groundwater) is close to the surface and where
the soils are very permeable, i.e. well-drained soils such as
loamy sands. Your local agricultural agencies can provide further
information on the type of soil in your area and the location of
- Precautionary statements: Labels of manufacturing-use products and
end-use products (EUPs) must bear the statements: (Hazards to
- WARNING: May be fatal if swallowed. Harmful if inhaled or
absorbed through the skin. Causes substantial but temporary eye
injury. Avoid breathing dust (vapor or spray mist). Avoid
contact with skin, eyes, or clothing. Do not get in eyes or on
clothing. Wear a face shield. Wash thoroughly with soap and
water after handling and before eating or smoking. Remove contam-
inated clothing and wash before reuse.; and
- Use of this product may be hazardous to your family's health.
This product has been determined to cause birth defects in
laboratory animals. Exposure of women of child-bearing age to
cyanazine should be avoided.
- Statements of practical treatment:
- If on skin: Wash with plenty of soap and water. Get medical
- If in eyes: Flush with plenty of water. Call a physician.
- If swallowed: Call a physician or Poison Control Center. Drink
1 or 2 glasses of water and induce vomiting by touching back of
throat with finger. Do not induce vomiting or give anything by
mouth to an unconscious person.
- Environmental hazard statement: The following specific statements
must appear on the labels of all manufacturing use products:
- Do not discharge effluent containing this product into lakes,
streams, ponds, estuaries, oceans, or public waters unless this
product is specifically identified and addressed in an NPDES
permit. Do not discharge effluent containing this product to
sewer systems without previously notifying the sewage treatment
plant authority. For guidance, contact your State Water Board or
Regional Office of the EPA.
- The labels of EUPs intended for outdoor use must bear one of the
following statements, depending on the formulation of the product:
- Granular products must bear the statement: Do not apply
directly to water or wetlands. In case of spills, collect for
user or properly dispose of the granules. Do not contaminate
water by cleaning of equipment or disposal of wastes.
- Non-granular products must bear the statement: Do not apply
directly to water or wetlands. Do not contaminate water by
cleaning of equipment or disposal of wastes.
- The label of all products (except those, if any, intended solely
for household use) must bear the appropriate container disposal
statement, as will be given in Appendix IV-5 of the guidance
- The required statements listed in this standard must appear on the
labels of all MUPs and EUPs released for shipment after June 30,
1985. After review of data to be submitted under this standard,
the Agency may impose additional label requirements.
- Summary of risk/benefit analysis: Cyanazine produces teratogenic
effects in laboratory animals. Exposure to the public through the
dietary route is not sufficiently large to exceed the risk criterion
in 40 CFR 162.11. Margins of safety are adequate for that route.
However, the dermal exposure rates of mixer/loaders and applicators
are comparable to levels at which effects occur in experimental
animals. This triggers the risk Criterion in 40 CFR 162.11, sending
cyanazine into the Special Review Process. The benefits of cyanazine
are primarily from its effectiveness as a herbicide to corn, which
accounts for 96% of total use. Available alternatives to cyanazine
do not have as broad a spectrum of weed control. The most widely
used alternative is atrazine, which may have more persistent residues
and leaches through the ground at the same rate as cyanazine. On
cotton (3% total use) the alternatives again do not provide as broad
a spectrum of weed control.
5. SUMMARY OF MAJOR DATA GAPS
Dates when major data gaps are due to be filled:
- Statement of composition (1), Discussion of formation of unintentional
ingredients (1), Preliminary analysis of samples (1), Certification
of limits (1,2), Analytical methods and data for enforcement of
limits (1,2), Density, Bulk Density, or Specific Gravity (1),
Dissociation Constant (1), Octanol/water partition coefficient (1),
pH (1,2), Oxidizing/Reducing Action (1,2), Flammability (1,2),
Explodability (1,2), Storage Stability (1,2), Livestock residues,
Plant residues, Animal residues, Storage stability data, Magnitude of
the residue for each food use, Hydrolysis, Photodegradation (water,
soil), Metabolism studies in lab, Mobility studies - leaching and
absorption/desorption, Dissipation studies in field, Primary eye
irritation (2,3,4), Primary dermal sensitization (4), Avian dietary
toxicity, and Acute toxicity to freshwater invertebrates - all due six
months after publication of the Standard.
- Monitoring of surface and groundwater - due 18 months after publica-
tion of the Standard.
- Reproduction (2-generation), Chromosomal aberration, and Other
genotoxic effects - due 20 months after publication of the Standard.
- Teratogenicity - due one year after publication of the Standard.
- 90-day feeding (rodent, non-rodent), and Oncogenicity - due four
years after publication of the Standard.
(1) - Data are required on the technical material.
(2) - Data are required on the 94% technical, which is used as a
manufacturing use product, and the 28.2% flowable intermediate.
(3) - Data are required on all wettable powder formulations.
(4) - Data are required on all liquid formulations.
6. CONTACT PERSON AT EPA
U.S. Environmental Protection Agency
401 M Street S.W.
Washington, DC 20460
THE INFORMATION PRESENTED IN THIS CHEMICAL INFORMATION FACT SHEET
IS FOR INFORMATIONAL PURPOSES ONLY AND NOT TO BE USED TO FULFILL
DATA REQUIREMENTS FOR PESTICIDE REGISTRATION AND REREGISTRATION.