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endosulfan (Thiodan) Chemical Profile 4/85


      CHEMICAL NAME:      6,7,8,9,10,10-Hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-
                          methano-2,4,3-benzodioxathiopin-3-oxide (56)


      TRADE NAME(S):      Thiodan, Tiovel (56)

      FORMULATION(S):     Wettable powders (35, 50%), emulsifiable concentrates
                          (17.5%,35%,50%, and 2 pounds and 3 pounds/gallon),
                          ULV (25%), granules (2,3,4,5%), dusts (1,2,3,4,5,6%)

      TYPE:               Organochlorine insecticide - miticide

      BASIC PRODUCER(S):  FMC Corp.                  Velsicol Chemical Corp.
                          Agr. Chem. Group           341 East Ohio Street
                          2000 Market St.            Chicago, IL 60611
                          Philadelphia, PA 19103

      STATUS:             Restricted use

      PRINCIPAL USES:  Controls aphids, thrips, beetles, foliar feeding
      larvae, mites, borers, cutworms, bollworms, bugs, whiteflies, leaf-
      hoppers, and slugs on deciduous, citrus, and small fruits, vegetables,
      forage crops, oil crops, fiber crops, grains, tobacco, coffee, tea,
      forest, ornamentals.  Controls termites and tsetse fly (56).

                                I.  EFFICACY

      Important Pests Controlled:  Aphids, beetles, bollworms, spittlebugs,
      termites, tsetse fly, leafhoppers, pear psylla, fleabeetles, stemborers,
      stinkbugs, boll weevils, loopers, corn earworms, peach twig borers,
      armyworms, cyclamen mites, mosquito pupae, and many others (8a).

                           II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:  C9 H6 Cl6 O3 S (62)

      MOLECULAR WEIGHT:   406.9 (62)

      PHYSICAL STATE:     Brown crystalline solid (technical product, at least
                          94% pure).  Endosulfan is a mixture of two stereo-
                          isomers: alpha-endosulfan, endosulfan (I), m.p. 109
                          C, is 64-67% of the technical grade; beta-endosulfan,
                          endosulfan (II), m.p. 213.3 C, is 29-32% (62).

      ODOR:               Of sulfur dioxide (technical product) (62)

      MELTING POINT:      70-100 C (technical product) (62)

      VAPOR PRESSURE:     1.2 Pa at 80 C (technical product) (62)

      SOLUBILITY:         0.32 mg/l water (alpha-endosulfan), 0.33 mg/l water
                          (beta-endosulfan) at 22 C (62).

                        III.  HEALTH HAZARD INFORMATION

      OSHA STANDARD:  None established

      NIOSH RECOMMENDED LIMIT:  None established

      ACGIH RECOMMENDED LIMIT:  TWA (Time Weighted Average) = 0.1 mg/m3;
                                STEL (Short Term Exposure Level) = 0.3 mg/m3
                                (deleted); skin notation (15c).


           A.  ACUTE TOXICITY

               DERMAL:  LD50 = 359 mg (in oil)/kg (rabbit) (62)
                        Nonirritant (11c)

               ORAL:    LD50 = 80-110 mg tech. (in oil)/kg (rat); 76 mg alpha
                        isomer/kg (rat); 240 mg beta isomer/kg (rat); 76.7 mg
                        tech./kg (dog) (62).

               INHALATION:  LC50 (Thiodan 50 WP) = >2 gm/liter of air (rat)
                            LD50 = 350 mg/m3 when the exposure is four hours
                              (male rat) (15b)

               EYES:    Nonirritant (11c)


           In 2-yr feeding trials rats receiving 30 mg/kg diet showed no
      ill-effect; in 1-yr feeding trials NEL for dogs was 3 mg/kg diet (62).
           Dogs tolerated endosulfan orally for a year at dosages up to 0.75
      mg/kg, the highest level tested.  Oral dosages of about 0.5
      mg/kg/day (dietary level of 10 ppm) for 2 years were associated with
      lower survival of female rats and reduced testis weight in males, but
      these findings were of doubtful statistical significance.
      Consistent histopathological findings were apparent only at a dosage
      ten times as great, which produced renal tubular damage and some
      hydropic change of the liver (15b).


           Hazardous to birds, fish, and beneficial insects.  Moderately
      hazardous to honey bees.  Biological magnification slight.  Not
      recommended for use on Concord grapes.  Injury reported on alfalfa,
      birch and chrysanthemums under greenhouse conditions (1).
           It is highly toxic to fish (LC50 (96-hr) for golden ide 2 ug/l
      water) but, in practical use, should be harmless to wildlife and to
      honeybees (62).

           Fish:  Endosulfan is highly toxic.  The LC50 of various fish
      species was determined to range between 0.001 and 0.05 ppm (11c).

           Wildlife Studies:  the LD50 values obtained are as follows:

      Species                              Male                       Female
      _______                              ____                       ______

      Bobwhite Quail                         50                          56
      Japanese Quail                        106                          85
      Mallard Ducks                         243                         205

           No significant difference in sex (11c).

           It is metabolised, in plants and mammals, to the corresponding
      sulphate which is toxicologically similar to endosulfan (the sulphite).
      For most fruits and vegetables 50% of the residue is lost in 3-7 days.
      There is no accumulation in milk, fat or muscle and it is excreted as
      conjugates of the diol and as other highly polar metabolites depending
      on the species (62).

      Approximate Residual Period:  7-15 days on plant surfaces; 1 season on
      unexposed surfaces (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:  Remove contaminated clothing and wash skin
                          thoroughly with soap and water.  Call a physician
                          immediately (11c).

           INGESTION:  Give a saline emetic (tablespoon of salt in glass of
                       water) and repeat until returns are clear.  Call a
                       physician immediately (11c).

           EYE CONTACT:  Flush with plenty of water.  Call a physician
                         immediately (11c).


           Endosulfan is a central nervous system stimulant.  There is no
      specific antidote.  If patient is convulsing, give pentobarbital (0.25
      to 0.50 gram) intravenously.  Otherwise phenobarbital (0.06 to 0.10
      gram) may be given orally.  Do not use oily laxatives as they increase
      absorption.  Patient should be under medical observation for at least
      24 hours in any case of suspected intoxication.  Electroencephalogram
      may show abnormal alpha wave activity (11c).

           Diazepam is the treatment of choice for convulsions.  If ingested,
      induce emesis, then administer magnesium sulfate and observe (56).


      GENERAL:  While dry Thiodan formulations will not support combustion,
      there is the possibility of them giving off sulfur dioxide fumes if a
      fire occurs where they are stored.  For liquid Thiodan formulations
      observe flammable caution statements.  No explosive hazard (for technical
      material) (11c).

      EXTINGUISHER TYPE:  Water spray, CO2, dry chemical, fog (16).

                             VII.  COMPATIBILITY

           Generally compatible except with alkaline materials (1).
      Incompatible with calcium arsentate, lime, or zinc sulfate plus lime.
      Compatible with other pesticides with which it might be used (11c).

                          VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING:  Do not breathe dust or spray mist.  Do not get in
      eyes, on skin, or on clothing.  Wash hands immediately after handling.
      Do not store Thiodan Miscible at temperatures below 20 F.  Provide
      general ventilation plus local exhaust at point of potential fume
      emission.  Protect E.C. from freezing (56).

      PROTECTIVE CLOTHING:  During commercial or prolonged exposure, wear
      clean clothing fastened at neck and wrists for dust protection, change
      clothing daily; wear clean synthetic rubber gloves and a mask or
      respirator of a type passed by MESA for endosulfan protection.
      Protective clothing also required for workers entering treated fields
      within 24 hours of application (56).

      PROTECTIVE EQUIPMENT:  During commercial or prolonged exposure, wear a
      mask or respirator of type passed by MESA for endosulfan protection


                                 (800) 424-9300

           Using respirator sweep up spill and use if possible or package for
      disposal (16).

                               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.

      11c. FMC Corporation.  1974.  Product manual:  Thiodan.  Middleport,

      15b. American Conference of Governmental Industrial Hygienists.  1971.
               Documentation of the threshold limit values for substances in
               workroom air with supplements for those substances added or
               changed since 1971, 3rd ed., 4th printing (1977).  Cincinnati,
               OH.  484 pp.

      15c. American Conference of Governmental Industrial Hygienists.  1984.
               TLVs:  threshold limit values for chemical substances and
               physical agents in the work environment and biological exposure
               indices with intended changes for 1984-85.  Cincinnati, OH.
               116 pp.

      16.  Agway, Inc., Chemical Division.  Material safety data sheet.

      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.