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Sodium Methyldithiocarb - Chemical Profile 10/84

                             sodium methyldithiocarbamate

      CHEMICAL NAME:      Sodium N-methyldithiocarbamate (56)

      TRADE NAME(S):      Vapam, VPM (48)

      FORMULATION(S):     Aqueous solutions (48)

      TYPE:               Soil fumigant-nematicide-fungicide

      BASIC PRODUCER(S):  Stauffer Chemical Co.
                          Nyala Farm Road
                          Westport, CT 06880

      STATUS:             General use

      PRINCIPAL USES:     Control of soil-borne species of nematodes and some
      fungus on a variety of crops (48).
           General purpose soil fumigant.  Highly effective in control of
      weeds and weed seeds, nematodes, and soil fungi. Penetration and
      effectiveness is improved somewhat by a water seal although this is not
      necessary (56).

                                   I.  EFFICACY

           To be developed.

                             II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:  C2 H4 N Na S2 (26)

      MOLECULAR WEIGHT:   129.2 (26)

      PHYSICAL STATE:     Colorless crystalline dihydrate (pure compound)

      SOLUBILITY:         722 g dihydrate/l water at 20 C (pure compound)

                          III.  HEALTH HAZARD INFORMATION





           A.  ACUTE TOXICITY

               DERMAL:    LD50 = 800 mg/kg (rabbit); irritant (26).
                          LD50 = 1300 mg/kg (rabbit, Vapam Soil Fumigant
                          Solution (29i).

               ORAL:      LD50 = 820 mg/kg (male rat) (26)
                          LD50 = 1700 mg/kg (female rat, Vapam Soil Fumigant
                          Solution) (29i)
                          LD50 = 1800 mg/kg (male rat, Vapam Soil Fumigant
                          Solution) (29i)

               INHALATION:  The acute inhalation LC50 is greater than 4.7
      mg/l in both male and female rats.  A single 4-hour inhalation exposure
      of 4.7 mg/l (greater than 85 percent respirable) produced decreased
      physical activity and blood-like stains about the face in female rats.
      A single 4-hour inhalation exposure of 4.7 mg/l (greater than 85 percent
      respirable) produced decreased physical activity, dyspnea, blood-like
      stains about the face, 6 to 14 percent decrease in mean body weights
      and 10 percent mortality in male rats (Vapam Soil Fumigant Solution)

               EYES:      Mild irritant to rabbit eyes (Vapam Soil Fumigant
      Solution (29i).


           To be developed.

                        IV.  ENVIRONMENTAL  CONSIDERATIONS

           Fumes toxic to living plants (48).
           This product is toxic to fish.  Keep out of lakes, streams and
      ponds.  Do not contaminate water sources by cleaning equipment or
      disposing of wastes (29i).


           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.

           SKIN CONTACT:  Immediately remove contaminated clothing wiping
      away excess material from the skin.  Under a safety shower, flush all
      affected areas with large amounts of water for at least 15 minutes.  Do
      not attempt to neutralize with chemical agents.  Obtain medical advice
      immediately (29i).

           INGESTION:     Immediately dilute the swallowed material by giving
      large quantities of water.  Induce vomiting by gagging the victim with
      a blunt object placed on the back of the victim's tongue.  Continue
      fluid administration until vomitus is clear.  Never give anything by
      mouth to an unconscious person.  Call a physician or the nearest Poison
      Control Center immediately (29i).

           INHALATION:    Remove from contaminated atmosphere.  If breathing
      has ceased, clear the victim's airway and start mouth-to-mouth
      artificial respiration, which may be supplemented by the use of a
      bag-mask respirator or a manually-triggered, oxygen supply capable of
      delivering one liter/second or more.  If the victim is breathing,
      oxygen may be delivered from a demand-type or continuous-flow
      inhalator, preferably with a physician's advice (29i).

           EYE CONTACT:   Immediately flush the eyes with large quantities of
      running water for a minimum of 15 minutes.  Hold the eyelids apart
      during the flushing to ensure rinsing of the entire surface of the eye
      and lids with water.  Do not attempt to neutralize with chemical
      agents.  Obtain medical attention as soon as possible.  Oils or
      ointments should not be used.  Continue the flushing for an additional
      15 minutes if the physician is not immediately available (29i).

                        VI.  FIRE AND EXPLOSION INFORMATION

      GENERAL:  This material is considered noncombustible.  However, under
      fire conditions it may decompose to give off toxic oxides of nitrogen
      and sulfur.  Vapors are extremely irritating to the respiratory tract
      and may cause breathing difficulty and pulmonary edema.  Symptoms may
      be delayed several hours or longer depending upon exposure.
           As in any fire, prevent human exposure to fire, smoke, fumes or
      products of combustion.  Evacuate nonessential personnel from the fire
      area.  When there is a potential for exposure to smoke, fumes, products
      of combustion, etc., firefighters should wear full-face, self-contained
      breathing apparatus and impervious clothing such as gloves, hoods,
      suits and rubber boots.  Use of contaminated buildings, area and
      equipment must be prevented until they are properly decontaminated

      EXTINGUISHER TYPE:  Use standard firefighting techniques in
      extinguishing fires involving this material - use water, dry chemicals,
      foam or carbon dioxide.  If drums are not leaking, keep cooled with a
      water spray.  High pressure water hose may spread product from broken
      containers increasing contamination hazards (29i).

                                VII.  COMPATIBILITY

           Corrosive to brass and copper (48).
           Upon dilution with water or on heating, the material decomposes
      and forms methyl isothiocyanate and hydrogen sulfide, both highly
      poisonous.  Use promptly after mixing with water.  Do not allow
      solution to stand.  This material is not compatible with acidic
      solutions (29i).

                            VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING:  Stable in concentrated solution but unstable on
      dilution.  Avoid contact with skin and eyes (56).
           Do not store below 0 F.  Product crystallizes at lower
      temperatures.  Warm or store at higher temperatures and mix to
      redissolve crystals and assure uniformity before use (29g).
           Do not store near feed or food (29g).

      PROTECTIVE CLOTHING:  Skin contact with liquid or its aerosol must be
      prevented through the use of impervious clothing, gloves and footwear,
      selected with regard for use condition exposure potential.  Eye contact
      with liquid or its aerosol should be avoided through the use of
      chemical safety glasses, goggles or face shield, selected with regard
      for use condition exposure potential (29i).

      PROTECTIVE EQUIPMENT:  When applying in enclosed areas wear a mask or
      respirator of a type approved by the U.S. Bureau of Mines for Vapam
      protection (29g).

                       IX.  PROCEDURES FOR SPILLS AND LEAKS

                                  (800) 424-9300

      Make sure all personnel involved in the spill cleanup follow good
   industrial hygiene practices.
           Small spills can be handled routinely.  Use adequate ventilation
   and wear an air-supplied respirator to prevent inhalation.  Wear
   suitable protective clothing to prevent skin and eye contact.  Use the
   following procedures:
      1.   Spread a suitable absorbent such as clay, sawdust or kitty litter
           on the spilled material.
      2.   Place sweepings in an appropriate chemical waste container.
      3.   Generously cover the contaminated areas with a common household
           detergent (e.g. Tide).  Using a stiff brush and small amounts of
           water, work the detergent into the spill material forming a
           slurry.  Do not splatter on one's self or bystanders, and
           completely avoid skin and eye contact with this material.  Brush
           the slurry into cracks and crevices and allow to stand for 2-3
      4.   Again spread absorbents on the slurried liquid and shovel the
           absorbed material into the container.
      5.   Repeat if necessary.
      6.   Flush the area with water while observing proper environmental
      7.   Seal container and dispose of in approved pesticide landfill or

           Large spills must be handled according to a predetermined plan.
      For assistance in developing a plan, contact the Agricultural Chemical
      Division, Stauffer Chemical Company, Westport, CT 06880 (29i).

                               X.  LITERATURE CITED

      26.  The Pesticide Manual:  A World Compendium, 6th ed.  1979.  C. R.
               Worthing, ed.  The British Crop Protection Council, Croydon,
               England.  655 pp.

      29g. Stauffer Chemical Company.  1982.  Specimen label:  Vapam soil
               fumigation solution for all crops.  Westport, CT.

      29i. Stauffer Chemical Company, Agricultural Chemical Division.  1980.
               Product safety information:  Vapam Soil Fumigant Solution.
               Westport, CT.

      48.  Harding, W.C.  1979-80.  Pesticide profiles, part two:  fungicides
               and nematicides.  Univ. Maryland, Coop. Ext. Service Bull.
               283, 22 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.