fenvalerate (Pydrin) Chemical Profile 3/85
CHEMICAL NAME: cyano(3-phenoxyphenyl)methyl 4-chloroalpha-
(1-methylethyl) benzeneacetate (56)
TRADE NAME(S): Pydrin, Ectrin (56)
FORMULATION(S): Pydrin in 2.4 pounds a.i. per gallon emulsible
concentrate. Presently packaged in 1-quart glass,
1-gallon plastic, and 5,30, and 55-gallon metal
containers. Ectrin in 10 gram eartags and 10% liquid
formulation in 1 quart container (56).
TYPE: Synthetic pyrethroid insecticide
BASIC PRODUCER(S): Shell Chemical Company, A Division of Shell Oil
P. O. Box 3871
Houston, TX 77001
SDS Biotech Corp.
7528 Auburn Rd.
P.O. Box 348
Painesville, OH 44077
STATUS: Restricted use
PRINCIPAL USES: Insects on fruit, field crops, and vegetables.
Pydrin was conditionally registered by EPA in early 1979 for use
on cotton, and in late 1980 for use on peanuts, potatoes, and pears
(dormant). Tolerances have been established for cotton, peanuts,
potatoes, pears, apples, peaches, pecans, filberts, cabbage, melons,
pumpkins, winter squash, summer squash, tomatoes, cucumbers, field corn,
sweet corn, dry beans, dry peas, broccoli, cauliflower, soybeans,
artichokes, eggplant, peppers, fat of milk, and meat and meat byproducts.
Ectrin used in dairy and beef cattle eartags for control of
hornflies, faceflies, Gulf Coast ticks, spinose ear ticks, and as an aid
to control stable flies and house flies (56).
Important Pests Controlled: Cotton bollworm, cotton leaf perforator,
leafhoppers, thrips, tobacco budworm, lygus bugs, and many lepidopterous
Gives good residual control with a fast knockdown (8a).
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C25 H22 Cl NO3 (62)
MOLECULAR WEIGHT: 419.9 (62)
PHYSICAL STATE: Viscous yellow or brown liquid, sometimes partly
crystallized at room temperature (technical grade)
ODOR: Mild chemical odor (56)
VAPOR PRESSURE: 37 uPa at 25 C (technical grade) (62)
SOLUBILITY: < 1 mg /l water at 20 C (technical grade) (62)
III. HEALTH HAZARD INFORMATION
OSHA STANDARD: None established
NIOSH RECOMMENDED LIMIT: None established
ACGIH RECOMMENDED LIMIT: None established - for xylene (solvent in
Pydrin): TWA (Time Weighted Average) = 435
mg/m3; STEL (Short Term Exposure Limit) =
655 mg/m 3 (18a).
A. ACUTE TOXICITY
DERMAL: LD50 = 2500 mg/kg (rabbit); >5000 mg/kg (rat) (56).
May be irritating to the skin (8a).
ORAL: LD50 = 451 mg/kg (DMSO, rat); >3200 mg/kg (aqueous
suspension, rat) (56).
LD50 = 451 mg/kg (rat), > 1600 mg/kg (domestic fowl)
INHALATION: Irritating to the nose and throat (18a)
EYES: Can cause eye irritation or damage (18a)
May be irritating to the eyes (8a).
B. SUBACUTE AND CHRONIC TOXICITY:
In 2-yr feeding trials NEL for rats was 250 mg/kg diet (62).
IV. ENVIRONMENTAL CONSIDERATIONS
Some hazard to fish, beneficial insects and honey bees. Biological
magnification unlikely. Nonphytotoxic (1). Pydrin is highly toxic to
bees and extremely toxic to fish (18a).
The LC50 (96 hr) for rainbow trout is 3.6 ug/l (62).
Approximate Residual Period: 1-3 weeks on plants or exposed surfaces (1).
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
FREQUENT SYMPTOMS AND SIGNS OF UNDUE EXPOSURE TO PYRETHRUM, PYRETHRINS,
PYRETHROIDS AND PIPERONYL BUTOXIDE
A STUFFY, RUNNY NOSE and scratchy throat from inhalation of partly
purified pyrethrum extract is the most common adverse effect of these
agents. Asthmatic WHEEZING may be precipitated by exposure of
predisposed individuals. Sudden bronchospasm, swelling of oral and
laryngeal mucous membranes, and shock (anaphylaxis) have been reported
after pyrethrum inhalation. Delayed appearance of dyspnea, cough and
fever, with patchy lung infiltrates on x-ray, suggest hypersensitivity
pneumonitis. Nervous irritability, tremors, and ataxis have occurred
rarely in persons who have had massive inhalation exposure to
pyrethrins. Halocarbon propellents in bug-bomb products present a risk
of CARDIAC ARRHYTHMIA and possibly fibrillation if inhaled to excess.
Hydrocarbons used as solvents in spray products are likely to result in
COUGH, FEVER, and CHEST PAIN (hydrocarbon pneumonitis) if these liquids
are inadvertently aspirated (25).
SKIN CONTACT: Irritating to skin. Wash thoroughly with soap and
water. If abnormal skin sensations occur (i.e., tingling, burning, or
itching), immediately apply vegetable oil to affected areas. Reapply
every 30 minutes if symptoms recur and use until symptoms are gone. Get
medical attention if irritation is severe (18a).
INGESTION: No specific antidote is known. In cases of ingestion
carry out gastric lavage with care to prevent aspiration. Treat
EYE CONTACT: Can cause eye irritation or damage. Flush with plenty
of water for 15 minutes. Get medical attention (18a).
NOTES TO PHYSICIAN:
If victim is not fully alert, empty stomach immediately by intubation,
aspiration, and lavage, using isotonic saline or 5% sodium
bicarbonate. Because many pesticides are dissolved in petroleum
distillates, emesis and intubation of the stomach involve a risk that
solvent will be aspirated, leading to chemical pneumonitis. Do not
administer or instill milk, cream, or other substances containing
vegetable or animal fats, which enhance absorption of lipophilic
substances, such as pyrethrins and pyrethroids.
Diazepam (Valium (TM)), 5-10 mg in adults, 0.1 mg/kg in children, given
orally or slowly IV, should control nervousness and tremors in rare
cases having these symptoms after extraordinary exposure to pyrethrins
and pyrethroids (25).
VI. FIRE AND EXPLOSION INFORMATION
Technical Pyrdrin has a high flash point and is a relatively
minor fire hazard. However, Pydrin 2.4 EC will burn if exposed to an
ignition source. Do not use, pour, or store near heat or open flame.
With sufficient heat, either product may decompose, releasing noxious
fumes such as hydrogen cyanide, which could be fatal if inhaled. Fire
fighters should use a supplied air pressure - demand self-contained
breathing apparatus for protection against both toxic and oxygen
deficient atmospheres. Respirators with canisters or cartridges should
not be used (18a).
Generally compatible with most insecticides and fungicides (1).
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Store in a locked cool place well away from water,
feed, or foodstuffs and inaccessible to animals or children. Keep away
from heat or open flames (18a). Avoid contact with mouth, eyes, and
PROTECTIVE CLOTHING: Wear neoprene rubber gloves if material could
contact hands. In addition to goggles, wear other clean, liquid-
resistant protective equipment (boots, body covering, hat, face shield)
as necessary to protect against spills or splashes (18a). While
handling, wear protective gloves and goggles or full face shield (56).
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
1. Isolate the affected area and keep out unauthorized personnel.
2. If anyone has been affected by Pydrin, remove the person from
continued exposure. Call a physician or poison control center and
give first aid.
3. If the leak is indoors, ventilate the area as thoroughly as
4. Stop any leaks by repositioning the containers or by patching or
otherwise repairing the leaks, but take care to avoid contact with
the insecticide. Pack the damaged containers in a salvage drum.
Fill the drum with compatible cushioning and absorbent material.
5. Cover the spill area with a generous amount of clay or other
absorbent materials, such as sawdust or earth. Never use alkaline
absorbents or soda ash in the cleanup. Ventilate the area. Sweep
the contaminated absorbent onto a shovel and put the sweepings in
another salvage drum. If leakage occurs on soil, dig up enough of
the surface to remove the contamination and place it in a salvage
For Decontamination of Contaminated Areas and Equipment
Wash down the affected areas and exposed equipment with water
containing a mild (low-alkaline) liquid household detergent, then
rinse with water. Absorb waste water as above or drain it to a
sump for future collection and disposal. Scoop up contaminated
absorbent and place it in the salvage drum (18a).
X. LITERATURE CITED
1. Harding, W.C. 1979. Pesticide profiles, part one: insecticides
and miticides. Univ. Maryland, Coop. Ext. Serv. Bull. 267.
8a. Thomson, W. T. 1976. Agricultural chemicals - book 1:
insecticides, acaricides, and ovicides. Revised ed. Thomson
Publ., Indianapolis, IN. 232 pp.
18a. Shell Chemical Company. 1981. Agricultural chemicals safety
manual: Pydrin insecticide safety guide. Houston, TX.
25. Morgan, D.P. 1982. Recognition and management of pesticide
poisonings, 3rd ed. U.S. Environmental Protection Agency,
Washington, DC. 120 pp.
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.
62. The Pesticide Manual: A World Compendium, 7th ed. 1983. C.R.
Worthing, ed. The British Crop Protection Council, Croydon,
England. 695 pp.