dienochlor (Pentac) Chemical Profile 4/85
CHEMICAL NAME: Bis(pentachloro-2,4-cyclopentadien-1-yl) (56)
DEC INGRED. CODE:
TRADE NAME(S): Pentac (56)
FORMULATION(S): Pentac Aquaflow (a 4-pound active/gallon water-base
flowable) is recommended for non-food use on outdoor and indoor
ornamental crops and interior plantings. Pentac WP (50% active wettable
powder) is recommended for non-food use only on indoor floral crops and
certain outdoor ornamental crops (56).
TYPE: Organochlorine miticide
BASIC PRODUCER(S): Zoecon Corp.
Agricultural Chemicals Division
P.O. Box 10975
Palo Alto, CA 94303
STATUS: General use
PRINCIPAL USES: A specific miticide very effective against most plant
damaging mites on ornamentals. Noteworthy is very low phytotoxicity of
formulations and lack of mite resistance to Pentac after nearly 20 years
of use (56).
Very effective against most plant damaging mites on ornamentals
including the two-spotted spider, tumid spider, strawberry spider,
spruce spider, citrus red, European red, carmine, clover, McDaniel,
privet, and broad mite (56).
No insecticidal activity. A slow acting material initially, so it
should be used in a preventative program or in combination with a knock-
down agent. Long residual action (8a).
It acts by interference with oviposition (62).
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C10 Cl10 (62)
MOLECULAR WEIGHT: 474.6 (62)
PHYSICAL STATE: Tan crystalline solid (pure compound) (62)
MELTING POINT: 122-123 C (pure compound) (62)
VAPOR PRESSURE: 1.3 mPa at 25 C (pure compound) (62)
SOLUBILITY: Sparingly soluble in water (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 = >3160 mg/kg (albino rabbit) (62)
Neither a primary irritant nor sensitizer to human
ORAL: LD50 = >3160 mg tech./kg (male albino rat) (62)
EYES: A single application of 3 mg to rabbit eyes
produced a slight irritation which subsided by the 6th
B. SUBACUTE AND CHRONIC TOXICITY:
To be developed.
IV. ENVIRONMENTAL CONSIDERATIONS
Little or no hazard to birds, fish or beneficial insects.
Relatively nonhazardous to honey bees. Biological magnification
Approximate Residual Period: 2-4 weeks on plants although initially
slow in action (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 POISONING BY ORGANOCHLORINE PESTICIDES
APPREHENSION, EXCITABILITY, DIZZINESS, HEADACHE, DISORIENTATION,
WEAKNESS, PARESTHESIAE, muscle twitching, tremor, tonic and clonic
CONVULSIONS (often epileptiform), and unconsciousness are the major
manifestations. Soon after ingestion, nausea and vomiting commonly
occur. When chemicals are absorbed dermally, apprehension, twitching,
tremors, confusion, and convulsions may be the first symptoms.
Respiratory depression is caused by the pesticide and by the petroleum
solvents in which these pesticides are usually dissolved. Pallor
occurs in moderate to severe poisoning. Cyanosis may result as
convulsive activity interferes with respiration (25).
SKIN CONTACT: Bathe and shampoo the victim vigorously with soap
and water if skin and hair have been contaminated (25).
INGESTION: If victim is alert and gag reflex is not depressed,
give Syrup of Ipecac to induce vomiting (adults and children 12 years
and older: 30 ml; children under 12: 15 ml), followed by 1-2 glasses of
INHALATION: Remove to fresh air (56).
EYE CONTACT: Immediately flush eyes with a directed stream of water
for at least 15 minutes. Call a physician (56).
NOTES TO PHYSICIAN:
CONTROL CONVULSIONS. DIAZEPAM (VALIUM (TM)) is a valuable
anticonvulsant. Adult dosage: 5-10 mg (1-2 ml) slowly, intravenously
(no faster than one ml per minute) or give total dose intramuscularly
(deep). Repeat in 2-4 hours if needed.
Dosage for children under 6 years or 23 kg in weight: 0.1 mg/kg (0.02
ml/kg) intravenously, no faster than half the total dose per minute, or
give total dose intramuscularly (deep). Repeat in 2-4 hours if
needed. Persons suffering SEVERE PROTRACTED CONVULSIONS may require
additional anticonvulsant medication. Agents that have been used
successfully in the past are pentobarbital (Numbutal(TM)), phenytoin
(Dilantin(TM)), thiopental (Pentothal(TM)), and succinylcholine
If the victim is NOT FULLY ALERT, empty the 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 serious
risk that solvent will be aspirated, leading to chemical pneumonitis.
DO NOT give epinephrine or other adrenergic amines, because of the
enhanced myocardial irritability induced by chlorinated hydrocarbons
VI. FIRE AND EXPLOSION INFORMATION
To be developed.
Generally compatible, but ordinarily would not be combined with
other materials (1).
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Causes moderate eye irritation. Avoid contact
with eyes. Avoid inhalation of spray mist. Wash thoroughly after
handling. Store in original container in a dry place separate from
reducing agents. Do not reuse package. Triple rinse and empty
flushings into spray tank. Empty package is to be disposed of in the
manner described as follows: Disposal: bury or burn in accordance with
local, state, or Federal regulations. Consult local or state
environmental authorities or Extension service for details. Do not
contaminate food, feed, ponds, lakes, and waterways including sewers and
domestic water supplies. Toxic to fish and other aquatic organisms.
Products stable for minimum of 2 years with normal storage (56).
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
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.
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.