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dienochlor (Pentac) Chemical Profile 4/85


      CHEMICAL NAME:      Bis(pentachloro-2,4-cyclopentadien-1-yl) (56)


      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).

                                 I.  EFFICACY

           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
                          skin (56).

               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
                        day (62).


           To be developed.

                        IV.  ENVIRONMENTAL  CONSIDERATIONS

           Little or no hazard to birds, fish or beneficial insects.
      Relatively nonhazardous to honey bees.  Biological magnification
      unlikely (1).

      Approximate Residual Period:  2-4 weeks on plants although initially
      slow in action (1).


           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
      Control Center.


      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
      water (25).

           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).


      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.

                                VII.  COMPATIBILITY

           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

                                  (800) 424-9300

                               X.  LITERATURE CITED

       1.  Harding, W.C.  1979.  Pesticide profiles, part one: insecticides
               and miticides.  Univ. Maryland, Coop. Ext. Serv. Bull. 267.
               30 pp.

       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.