sethoxydim (Poast) Chemical Profile 3/85
CHEMICAL NAME: 2-[1-(ethoxyimino)butyl]-5-[2-ethylthio)propyl]-3-
TRADE NAME(S): Poast (58)
FORMULATION(S): Liquid emulsifiable concentrate (1.5 lb/gal - 184
BASIC PRODUCER(S): Nippon Soda Co., Ltd.
2-2-1, Ohtemachi, Chiyoda-kv,
Tokyo 100, Japan
BASF Wyandotte Corp.
100 Cherry Hill Rd.
Parsippany, NJ 07054
PRINCIPAL USES: For selective postemergence control of annual and
perennial grasses in soybeans, cotton, peanuts, sugar beets, flax, rape
seed (Canola/Canada), alfalfa, vegetables, and many other
dicotyledoneous crops (56).
APPLICATION METHOD(S): Ground or aerial postemergence spray (58).
Important Weeds Controlled: All annual grasses except Poa spp. and
most perennial grasses.
All broadleaf plants and sedges are tolerant to this product.
Rainfall within 4-5 hours of application will not reduce grass control.
Noticeable control of perennials the following season has been
observed. Some fesque species are tolerant (8b).
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C17 H29 O3 NS (58)
MOLECULAR WEIGHT: 327.5 (58)
PHYSICAL STATE: Oily liquid, amber (pure compound) (58)
ODOR: Odorless (pure compound) (58)
DECOMPOSITION TEMPERATURE: Unstable at room temperature if
BOILING POINT: >90 C/3 x 10-5 mmHg (pure compound) (62)
VAPOR PRESSURE: 1.6 x 10-7 mmHg at 25 C (pure compound) (58)
SOLUBILITY: 25 - 4700 mg/l water at 20 C (pH 4-7) (pure
III. HEALTH HAZARD INFORMATION
OSHA STANDARD: None established
NIOSH RECOMMENDED LIMIT: None established
ACGIH RECOMMENDED LIMIT: None established
A. ACUTE TOXICITY
DERMAL: LD50 = >5000 mg/kg (rat) (62).
Product is non-toxic by dermal route. Dermal
irritation in rabbits from formulation is moderate.
The active ingredient has low dermal toxicity, is
non-irritating to skin and is not a skin sensitizer
LD50 >4 g/kg (rat, formulated product) (65b).
ORAL: LD50 = 3200 mg/kg (rat) (62).
LD50 = 4920 mg/kg (rat, formulated product) (56).
LD50 = 2676 - 3,125 mg/kg (rat, technical compound)
INHALATION: Rat inhalation LC50 for one hour is >30 mg/l for
formulated compound. The active ingredient has low
inhalation toxicity (58).
EYES: Eye irritation in rabbits from formulation is moderate.
The active ingredient is nonirritating to eyes (58).
B. SUBACUTE AND CHRONIC TOXICITY:
In a 90-day dietary rat and mouse study the minimum effect level
was 900 ppm.
In a 6-month dietary dog study, the minimum effect level was 600
For Active Ingredient:
Teratogenicity (rat and rabbit) - negative.
Reproduction studies (2 generations rat) - negative (65b).
IV. ENVIRONMENTAL CONSIDERATIONS
Behavior In Or On Soils
1. Adsorption and leaching characteristics in basic soil types:
These characteristics are under investigation.
2. Microbial breakdown: Under investigation.
3. Loss from photodegradation and/or volatilization: Photolysis is
under investigation. Loss from volatilization is mimimal.
4. Resultant average persistence at recommended rates:
Soil Half-Life of Parent
loamy sand pH 6.8 4-5 days
loam pH 7.4 11 days
Soil persistence is rather short and the magnitude depends on soil
type, moisture, and possibly other environmental conditions
still to be investigated. Efficiency is not dependent upon
soil persistence, but soil activity prevents germination of
grasses immediately after application (58).
The technical formulation has demonstrated low toxicity to rodents,
rabbits, birds, fish, aquatic invertebrates and pollinating insects (58).
V. EMERGENCY AND FIRST AID PROCEDURES
The chemical information provided below has been condensed from
original source documents, primarily from "Recognition and Management
of Pesticide Poisonings", 3rd ed. by Donald P. Morgan, which have been
footnoted. This information has been provided in this form for your
convenience and general guidance only. In specific cases, further
consultation and reference may be required and is recommended. This
information is not intended as a substitute for a more exhaustive
review of the literature nor for the judgement of a physician or other
If poisoning is suspected, do not wait for symptoms to develop.
Contact a physician, the nearest hospital, or the nearest Poison
EFFECTS OF OVEREXPOSURE: Contact with eyes causes irritation,
redness, corneal clouding which may persist a few days. Prolonged skin
contact produces irritation, redness and swelling. Irritating to the
nose, throat and lungs if mists are inhaled. If swallowed may cause
sedation, stomach upset, diarrhea, possible liver damage (65b).
Ataxia, sedation, lachrymation, salivation, tremor, hematuria,
SKIN CONTACT: Wash skin thoroughly with soap and water. Remove
contaminated clothing and launder before wearing again. If irritation
develops, get medical attention (65b).
INGESTION: If swallowed, do not induce vomiting. Consult a
physician at once (65b).
INHALATION: If inhaled, move to fresh air. Aid breathing, if
necessary. If irritation develops get medical attention (65b).
EYE CONTACT: Flush with flowing water at least 25 minutes.
Consult a physician for eyes (65b).
VI. FIRE AND EXPLOSION INFORMATION
GENERAL: Flash point 146 F (T.C.C.). Flammability limits in air (% by
volume): Lower 1%, Upper 7%. Firefighters should be equipped with
full turn-out gear and self-contained breathing apparatus (65b).
EXTINGUISHER TYPE: Water fog, foam, CO2, dry chemical (65b).
No incompatibilities known. Non-corrosive (58).
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Storage stability: 2 years (tests continuing)
(58). Keep out of reach of children. Avoid prolonged contact with
skin or clothing. Do not get in eyes. Do not take internally (65b).
PROTECTIVE CLOTHING: Goggles or side shield safety glasses, as
conditions warrant (65b).
PROTECTIVE EQUIPMENT: Cannister or cartridge respirator for herbicides
and hydrocarbon solvent mists if exposure to spray mist or vapors will
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
Wear rubber gloves, goggles and boots when cleaning up liquid
spill. Cover contaminated area with absorbent material until dry.
After absorbent is removed, wash down the area with trisodium
phosphate, household lye. Poast is a regulated product. Spills should
be contained, absorbed and placed in suitable containers for disposal
in an RCRA licensed facility (65b).
X. LITERATURE CITED
8b. Thomson, W.T. 1981. Agricultural chemicals - book 2:
herbicides. Revised ed. Thomson Publications, Fresno, CA.
56. Farm Chemicals Handbook, 70th ed. 1984. R. T. Meister, G. L.
Berg, C. Sine, S. Meister, and J. Poplyk, eds. Meister
Publishing Co., Willoughby, OH.
58. Weed Science Society of America, Herbicide Handbook Committee.
1983. Herbicide handbook of the weed science society of
America, 5th ed. Weed Science Society of America, Champaign,
IL. 515 pp.
62. The Pesticide Manual: A World Compendium, 7th ed. 1983. C.R.
Worthing, ed. The British Crop Protection Council, Croydon,
England. 695 pp.
65b. BASF Wyandotte Corporation. 1982. Material safety data sheet:
sethoxydim. Wyandotte, MI.