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phosphamidon (Dimecron) Chemical Profile 8/90


      CHEMICAL NAME:      O,O-dimethyl-O-(2-chloro-2-diethyl carbamoyl-
                          1-methyl-vinyl) phosphate (56)

      TRADE NAME(S):      Dimecron (56)

      FORMULATION(S):     Liquid (8 pounds active gallon), soluble
                          concentrates (20, 50, and 100% w/v) (56).

      TYPE:               Organophosphate insecticide

      BASIC PRODUCER(S)   Ciba-Geigy
                          P.O. Box 18300
                          Greensboro, North Carolina 27419

                          Chevron Chemical Co./Ortho Div.
                          940 Hensley Street
                          Richmond, CA 94804

      STATUS:             Restricted use.  Voluntary cancellation by
                          manufacturer (Ciba-Geigy) in May 1990.

      PRINCIPAL USES:  Main use against sucking insects, stemborers in rice,
      and against aphids in various crops (56).

                                   I.  EFFICACY

      Important Pests Controlled:  Aphids, stemborers, lygusbugs, leafhoppers,
      leaf miners, spruce budworm, beetles, thrips, codling moth, grasshoppers,
      mites, scale, bollworms, Mexican bean beetles, white flies and many
      others (8a).
           A systemic translocated compound through both the roots and the
      leaves.  A selective compound with only slight contact and practically
      no ovicidal activity.  When mixed with Phaltan (fungicide) a synergistic
      effect occurs (8a).

                             II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:  C10 H19 Cl NO5 P (62)

      MOLECULAR WEIGHT:   299.7 (62)

      PHYSICAL STATE:     Yellow liquid (pure compound) (62)

      BOILING POINT:      94 C/0.04 mmHg (pure compound) (62)

      VAPOR PRESSURE:     3.3 mPa at 20 C (pure compound) (62)

      SOLUBILITY:         Completely miscible in water at 20 C (pure compound)

                          III.  HEALTH HAZARD INFORMATION

      OSHA STANDARD:  None established

      NIOSH RECOMMENDED LIMIT:  None established

      ACGIH RECOMMENDED LIMIT:  None established


           A.  ACUTE TOXICITY

               DERMAL:  LD50 = 374 mg/kg (rat); slight irritant to skin of
                          rabbits (62).
                        LD50 = 267 mg/kg (rabbit) (56)

               ORAL:    LD50 = 17.4 mg/kg (rat) (62)


           In 2-yr feeding trials the NEL was:  for rats 1.25 mg/kg daily; for
      dogs 0.1 mg/kg daily (62).

           Animals placed in an atmosphere containing 0.125 mg/l of
      phosphamidon for 6 hours a day, 5 days a week for a period of 90 days
      did not show any marked toxic effects (17a).

                        IV.  ENVIRONMENTAL  CONSIDERATIONS

           Moderately hazardous to birds, fish and beneficial insects.
      Hazardous to honey bees.  Biological magnification unlikely.  Injury has
      been reported on certain varieties of fruits and ornamentals (1).

           It is highly toxic to birds and honeybees (62).

           Fish toxicity:  maximum level (ppm) no effect = 100.0
                           minimum level (ppm) complete kill = 1000.0 (17a).

           In tests conducted in Canada, the short term mortality of young
      salmon and trout in streams sprayed with phosphamidon was no greater
      than that in the unsprayed control site.  Phosphamidon applied at
      one pound of actual per acre did not affect oysters or the
      microorganisms used for food by oysters (17a).

           Phosphamidon applied to wooded areas at one pound of actual per
      acre did not affect deer, rabbits, mice, chipmunks or toads.  However,
      some effects on birds have been observed (17a).

           Predaceous insect and mite populations have not been seriously
      reduced by applications of phosphamidon insecticide (17a).

      Approximate Residual Period:  2 weeks as systemic in plants; short life
      in soil (1).  The initial half-life in and on plants is 1 to 5 days as
      a rule (56).


           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.


           Symptoms of acute poisoning develop during exposure or within 12
      hours (usually within four hours) of contact.  HEADACHE, DIZZINESS,
      CRAMPS, DIARRHEA, and SWEATING are common early symptoms.  Blurred or
      dark vision, confusion, tightness in the chest, wheezing, productive
      cough, and PULMONARY EDEMA may occur.  Incontinence, unconsciousness
      and convulsions indicate very severe poisoning.  SLOW HEARTBEAT,
      salivation, and tearing are common.  TOXIC PSYCHOSIS, with manic or
      bizarre behavior, has led to misdiagnosis of acute alcoholism.  Slowing
      of the heartbeat may rarely progress to complete sinus arrest.
      RESPIRATORY DEPRESSION may be fatal.  Continuing daily absorption of
      organophosphate at intermediate dosage may cause an INFLUENZA-LIKE
      ILLNESS characterized by weakness, anorexia, and malaise (25).

           SKIN CONTACT:  Bathe and shampoo victim with soap and water if
      there is any chance that skin and hair are contaminated (25).

           INGESTION:  If victim is alert and respiration is not
      depressed, give Syrup of Ipecac, followed by 1-2 glasses of water to
      induce vomiting.  Adults (12 years and over):  30 ml; children:  15 ml


      Administer ATROPINE SULFATE intravenously, or intramuscularly, if IV
      injection is not possible.
      In MODERATELY SEVERE poisoning:  Adult dosage:  0.4-2.0 mg repeated
      every 15 minutes until atropinization is achieved:  tachycardia (pulse
      of 140 per minute), flushing, dry mouth, dilated pupils.  Maintain
      atropinization by repeated doses for 2-12 hours or longer depending on
      severity of poisoning.
      Dosage for children under 12 years:  0.05 mg/kg body weight, repeated
      every 15 minutes until atropinization is achieved.  Maintain
      atropinization with repeated dosage of 0.02-0.05 mg/kg.
      SEVERELY POISONED individuals may exhibit remarkable tolerance to
      atropine; two or more times the dosages suggested above may be needed.
      Administer PRALIDOXIME (Protopam (TM)-Ayerst, 2-PAM) in cases of severe
      poisoning in which respiratory depression, muscle weakness and
      twitchings are severe.
      Adult dosage:  1.0 gm intravenously at no more than 0.5 gm per minute.
      Child's dose (under 12 years):  20-50 mg/kg (depending on severity of
      poisoning) intravenously, injecting no more than half the total dose
      per minute.
      Dosage of pralidoxime may be repeated in 1-2 hours, than at 10-12 hour
      intervals if needed.  In very severe piosonings, dosage rates may be
      doubled (25).

                        VI.  FIRE AND EXPLOSION INFORMATION

           To be developed.

                                VII.  COMPATIBILITY

           Corrosive to and decomposed by iron and alkaline materials (1).
      Do not mix with copper oxychloride.  Do not combine with captan, folpet,
      or sulfur.  Non-corrosive.  Compatible with other pesticides (8a).

                            VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING:  Not for use or storage in or around the home
      (17b).  Poisonous if swallowed, inhaled, or absorbed through skin.  Do
      not contaminate feed or foodstuffs.  Do not get in eyes, on skin or
      clothing.  Do not breathe mist.  Keep container closed.  Wash thoroughly
      after handling.  Do not drink any alcoholic beverage before or during
      spraying since alcohol promotes absorption of organic phosphates (56).

      PROTECTIVE CLOTHING:   Wear natural rubber gloves, protective clothing,
      and goggles (17b).

      PROTECTIVE EQUIPMENT:  Wear a mask or respirator of a type passed by
      the U. S. Bureau of Mines for phosphamidon protection (17b).

                       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.

      17a. Chevron Chemical Company, Ortho Division.  1970.  Experimental
               data sheet:  Ortho phosphamidon.  San Francisco, CA.

      17b. Chevron Chemical Company, Ortho Division.  1974.  Specimen label:
               Ortho phosphamidon 8 spray.  San Francisco, CA.

      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.