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dichlorprop (Weedone, Cornox) Herbicide Profile 3/85

                                    dichlorprop
      CHEMICAL NAME:      2-(2,4-dichlorophenoxy)propionic acid (58)
      TRADE NAME(S):      Weedone, Cornox (58)
      FORMULATION(S):     Aqueous solutions of potassium or amine salt;
                          isooctyl and butyl esters (56).
      TYPE:               Chlorophenoxy herbicide
      BASIC PRODUCER(S):  SDS Biotech Corp.
                          7528 Auburn Rd.
                          P.O. Box 348
                          Painesville, OH 44077
      STATUS:             General use
      PRINCIPAL USES:  Dichlorprop is a translocated postemergence
      herbicide effective in the control of some Polygonum sp. and other
      weeds in small grain cereals.  It may be used either alone or in
      combination with other herbicides such as MCPA, benazolin, and
      dicamba.  The latter mixture is an extremely effective broad spectrum
      herbicide controlling such economically important weeds as Anthemis
      spp., Matricaria spp., Stellaria media, Galium aparine, as well as
      Polygonum spp.  Dichlorprop is also used for brush control in
      nonagricultural land (58).
      APPLICATION METHOD(S):  Postemergence foliage application (58).
                                    I.  EFFICACY
           Particularly effective for the control of Polygonum persicaria,
      P. lapathifolium and P. convolvulus.  It also controls Galium aparine
      and Stellaria media but is not consistently effective against P.
      aviculare (62).
                              II.  PHYSICAL PROPERTIES
      MOLECULAR FORMULA:  C0 H8 Cl2 O (58)
      MOLECULAR WEIGHT:   235.1 (58)
      PHYSICAL STATE:     White to tan crystalline solid (pure compound)
                          (58); yellowish solid (tech. a.i.) (56).
      ODOR:               Faint phenolic odor (pure compound) (58)
      MELTING POINT:      116 - 117.5 C (pure compound) (58); 117.5 - 118.1 C
                          (technical) (56); 114 C (technical grade) (62).
      VAPOR PRESSURE:     Negligible at room temperature (62)
      SOLUBILITY:         0.71 g/l water at 28 C (pure compound) (58); 825
                          ppm water at room temperature (tech. a.i.) (56).
                          III.  HEALTH HAZARD INFORMATION
      OSHA STANDARD:  None established
      NIOSH RECOMMENDED LIMIT:  None established
      ACGIH RECOMMENDED LIMIT:  None established
      TOXICOLOGY
           A.  ACUTE TOXICITY
               DERMAL:  LD50 = 1,400 mg/kg (mouse); 2.4% of solution did
                        not irritate skin (58).
               ORAL:    LD50 = 800 mg/kg (rat, tech. a.i.) (56).
                        LD50 = 400 mg/kg (mouse) (58).
               EYES:    A 1% solution did not irritate eyes (58).
           B.  SUBACUTE AND CHRONIC TOXICITY:
           No effect noted in rats fed 12.4 mg/kg per day for 90 days (58).
           In 98-day feeding trials no toxic effect was observed in rats
      receiving 12.4 mg/kg daily, though slight liver hypertrophy occurred at
      50 mg/kg daily (62).
                         IV.  ENVIRONMENTAL CONSIDERATIONS
           LC50 (48-hr) for bluegill was 165 mg dichlorprop-(dimethyl-
      ammonium)/l; 16 mg dichloroprop-isoctyl)/l; 1.1 mg dichlorprop-(2-
      butoxyethyl)/l (62).
                       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 substitute 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.
      FREQUENT SYMPTOMS AND SIGNS OF POISONING
           Chlorophenoxy compounds are moderately IRRITATING to skin and
      mucous membranes.  Inhalation of sprays may cause burning sensations in
      the nasopharynx and chest, and coughing may result.  Prolonged
      inhalation sometimes causes dizziness.
           When INGESTED, high concentrations of chlorophenoxy compounds may
      irritate the mouth, throat, and gastrointestinal tract.  Prompt EMESIS,
      CHEST PAIN (from esophagitis), ABDOMINAL PAIN, and DIARRHEA commonly
      ensue.  Injury to the GI tract does not usually progress to ulceration
      or perforation.  Absorbed chlorophenoxy compounds have caused
      FIBRILLARY MUSCLE TWITCHING, skeletal muscle tenderness, and MYOTONIA
      (stiffness of muscles of the extremities).  Ingestion of very large
      amounts has produced METABOLIC ACIDOSIS, fever, tachycardia,
      hyperventilation, vasodilatation and sweating.  Particular cases have
      been characterized by coma and convulsions (25).
           SKIN CONTACT:  BATHE and SHAMPOO with soap and water to remove
      chemicals from skin and hair.  Individuals with chronic skin disease or
      known sensitivity to chemicals should either avoid using these
      herbicides or take extraordinary measures to avoid contact (25).
           INGESTION:  If substantial amounts of chlorophenoxy compounds have
      been INGESTED, spontaneous emesis usually occurs.  Ordinarily this
      empties the stomach as effectively as intubation and lavage.  If
      vigorous emesis has not occurred and IF VICTIM IS FULLY ALERT, induce
      EMESIS with SYRUP OF IPECAC (adults 12 years and older, 30 ml; children
      under 12 years, 15 ml), followed by 1-2 glasses of water.  Following
      emesis, administer 30-50 gm of ACTIVATED CHARCOAL in a slurry of 6-8
      ounces tap water, to limit absorption of herbicide remaining in the gut
      (25).
           INHALATION:  If symptoms of illness occur during or following
      inhalation of spray, REMOVE victim FROM CONTACT with the material for
      at least two days.  Allow subsequent contact with chlorophenoxy
      compounds only if effective respiratory protection is practiced (25).
           EYE CONTACT:  FLUSH contaminating chemicals from eyes with copious
      amounts of clean water for 10-15 minutes (25).
      NOTES TO PHYSICIAN:
      1.  IF CONSCIOUSNESS LEVEL IS DEPRESSED or other signs of NEUROTOXICITY
          appear, SUSPECT additional or alternative ingested toxicants.
          Evacuate the stomach by INTUBTION, ASPIRATION, and LAVAGE.  Because
          petroleum distillates are commonly included in chlorophenoxy
          formulations, gastric intubation incurs a risk of hydrocarbon
          pneumonitis from aspiration.  For this reason:
          A.  If victim is unconscious or obtunded and facilities are at
              hand, insert an ENDOTHRACHEAL TUBE (cuffed, if available) prior
              to gastric intubtion.
          B.  Keep victim's HEAD BELOW LEVEL OF THE STOMACH during intubation
              and lavage (Trendelenburg, or left lateral decubitus, with head
              of table tipped downward).  Keep victim's head turned to left.
          C.  ASPIRATE PHARYNX as regularly as possible to remove gagged or
              vomited stomach contents.
          After aspiration of gastric contents and washing of stomach,
          instill 30-50 gm of ACTIVATED CHARCOAL in 3-4 ounces of water
          through the stomach tube to limit absorption of remaining toxicant.
          Do NOT instill milk, cream, or other materials containing vegetable
          or animal fats, as these are likely to enhance absorption.
      2.  If bowel movement has not occurred in 4 hours and patient is fully
          conscious, give SODIUM SULFATE, 0.25 gm/kg, as a cathartic.
          Magnesium sulfate and citrate, in comparable dosages, are equally
          suitable if renal function is adequate.  Retained magnesium may
          depress CNS function.
      3.  In SEVERE POISONINGS by very large amounts of ingested
          chlorophenoxy acids, forced ALKALINE DIURESIS may save the victim's
          life.  Assess serum electrolyte concentrations, and serum and urine
          pH.  If a metabolic acidosis is present, infuse solutions of sodium
          bicarbonate at rates sufficient to keep the urine distinctly
          alkaline, continuing until plasma concentrations of chlorophenoxy
          compounds are less than about 10 ug/ml.  (Prescott, L.F. et al.,
          Br. J. Clin. Pharmacol. 7:11 (1979) (25).
                        VI.  FIRE AND EXPLOSION INFORMATION
           To be developed.
                                VII.  COMPATIBILITY
           Dichlorprop is corrosive to metals in the presence of water;
      concentrated solutions (480 g a.e./l) do not corrode tin plate or iron
      if pH is greater than or equal to 8.6 and temperature <70 C (62).
                             VIII.  PROTECTIVE MEASURES
      STORAGE AND HANDLING:  Avoid spray drift to susceptible broadleaf
      plants that are desirable such as cotton, soybeans, and tomatoes.  If
      stored below freezing, it may be necessary to warm to 40 F and agitate
      before using (56).
                        IX.  PROCEDURES FOR SPILLS AND LEAKS
                      IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
                                   (800) 424-9300
                       PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
                               X.  LITERATURE CITED
      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.
      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.
      3/20/85