mefluidide (Embark) Herbicide Profile 3/85
CHEMICAL NAME: N-[2,4-Dimethyl-5-[[(trifluoromethyl)sulfonyl]amino
]phenyl] acetamide (56)
TRADE NAME(S): Embark, Vistar, Mefluidide (56)
FORMULATION(S): 2-S; Diethanolamine salt of mefluidide; equivalent
to 2 pounds of mefluidide per gallon (56).
TYPE: Herbicide - growth regulator
BASIC PRODUCER(S): 3M Company
St. Paul, MN 55144
STATUS: General use
PRINCIPAL USES: Embark is registered as a plant growth regulator to
suppress seedhead formation and to regulate the vegetative growth of
various turfgrass species and woody ornamentals.
Vistar is registered as a postemergence herbicide in soybeans for
the control of seedling and rhizomatous johnsongrass, shattercane,
volunteer corn, volunteer wheat, and volunteer sorghum. It is also
labeled for use in tank mix with Basagran herbicide and as a sequential
application with Blazer herbicide to control a wide spectrum of grass
and broadleaf weeds (56).
APPLICATION METHOD(S): Mefluidide may be applied foliarly with properly
calibrated ground equipment to actively growing turf before or after
mowing. Ornamental and nonornamental woody plants may be sprayed to
runoff with a boom sprayer just prior to or following trimming and
shaping. Application for the control of weeds in soybeans may be made
when the crop is in the 2 to 6 trifoliate stage of growth (8b).
Important Weeds Controlled: Johnsongrass, shattercane, volunteer corn
and volunteer sorghum (8b).
Rainfall within 8 hours after application may effect results
adversely. Supresses the weed growth and often controls it. Control
occurs as a twisting and stunting of the plant. Initial effects may not
be seen for 10 days. Poor control will be obtained if weeds are under
stress at time of application (8b).
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C11 H13 F3 N2 O3 S (62)
MOLECULAR WEIGHT: 310.3 (62)
PHYSICAL STATE: Colorless crystalline solid (pure compound) (62)
ODOR: Odorless (pure compound) (58)
MELTING POINT: 183-185 C (pure compound) (62)
VAPOR PRESSURE: <13 mPa at 25 C (pure compound) (62)
SOLUBILITY: 180 mg/l water at 23 C (pure compound) (62)
III. HEALTH HAZARD INFORMATION
OSHA STANDARD: None established
NIOSH RECOMMENDED LIMIT: None established
ACGIH RECOMMENDED LIMIT: None established
A. ACUTE TOXICITY
DERMAL: LD50 = >20,000 mg/kg (rabbit) (Embark PGR) (57a).
LD50 = >4000 mg/kg (rabbit) (62).
Rabbits primary skin irritation study - no
irritation to abraded and nonabraded skin (58).
ORAL: LD50 = >1920 mg tech/kg (mice); >4000 mg/kg (rat)
INHALATION: Rats 4-hr acute aerosol inhalation LC50 - >8.5
mg/liter of air (54).
EYES: Mildly irritating to the rabbit eye (62).
B. SUBACUTE AND CHRONIC TOXICITY:
No teratogenic effect was observed in rabbits and no mutagenic
effect was observed in Salmonella typhimurium (62).
Dogs 90-day feeding no-effect at 1000 ppm in diet; rats 90-day
feeding no-effect at 6000 ppm in diet (58).
IV. ENVIRONMENTAL CONSIDERATIONS
The acute oral LD50 for mallard ducks is >4640 mg/kg (62).
The LC50 (5d) for mallard duck and bobwhite quail (observed on the
8th day) was >10,000 mg/kg diet. The LC50 (96h) for rainbow trout and
bluegill is >100 mg/l (62).
Behavior In or On Soils
1. Adsorption and leaching characteristics in basic soil types:
Mefluidide and/or its breakdown products will leach in soil.
Organic matter and acidic soil conditions have a retarding effect
on leaching characteristics. Adsorption on the soil after short
(3 hr) contact periods is insignificant.
2. Microbial breakdown: Microbial acion does play a part in
the breakdown of mefluidide in soil.
3. Loss from photodecomposition and/or volatilization: Mefluidide on
dry soil surfaces is relatively stable to photodecomposition;
however, in aqueous solutions mefluidide is susceptible to
photodecoposition. Volatilization is considered to be minor.
4. Persistence in soils at recommended rates: The chemical is not
persistent in soil, and has a half life of 2 days (58).
Trout 4-day LC50 >1200 ppm
Bluegill 4-day LC50 1600 ppm
Ducks 8-day LC50 >1000 ppm in diet
Quail 8-day LC50 >1000 ppm in diet (58)
LC50 Rainbow trout = >1000 ppm (Embark PGR) (57a)
LC50 Bluegill sunfish = >1000 ppm (Embark PGR) (57a)
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 sub-
stitute for a more exhaustive review of the literature nor for the
judgement of a physician or other trained professional.
If poisoning is suspected, do not wait for symptoms to develop.
Contact a physician, the nearest hospital, or the nearest Poison
SYMPTOMS OF POISONING: Absence of adverse toxicological effects
precludes description of symptoms of poisoning (58).
SKIN CONTACT: Wash thoroughly with soap and water in case of skin
EYE CONTACT: In case of eye contact, immediately flush eyes with
water for at least 15 minutes and call a physician (54).
VI. FIRE AND EXPLOSION INFORMATION
Nonflammable - formulation contains water (54).
Possible incompatibiities: Liquid fertilizers which are acidic in
nature. Slight corrosion of metallic sprayer parts may occur upon
prolonged contact (58).
Tests with spray solutions of Embark PGR on metals such as
galvanized and stainless steel, zinc, aluminum, copper, yellow brass
and bronze and on eleven types of granite and marble resulted in no
staining or corrosion (57a).
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Formulation exhibited good stability during
accelerated aging at 60 C for up to 9 months. Store formulation at
temperatures above 4 C. Avoid inhalation, ingestion, or contact with
the skin or eyes (58).
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
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.
57a. 3M Company, Agrichemicals. 1978. Product performance manual:
Embark 2-S, plant growth regulator. St. Paul, MN.
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.
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