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Glyphosate - Chemical Profile 2/85


      CHEMICAL name:      Isopropylamine salt of N-(phosphonomethyl)glycine

      TRADE name(S):      Roundup (56)

      FORMULATION(S):     Roundup is sold as an aqueous solution of the
                          isopropylamine salt of glyphosate and wetting
                          agents (56).

      TYPE:               Herbicide

      BASIC PRODUCER(S):  Monsanto Agricultural Products Co.
                          800 N. Lindberg Blvd.
                          St. Louis, MO 63166

      STATUS:             General use

      PRINCIPAL USES:  For control of many annual and perennial grasses and
      broadleaf weeds plus many tree and woody brush species in cropland
      and noncrop sites.  A foliar-applied translocated herbicide, it may be
      applied in spring, summer, or fall to undesirable vegetation by boom
      equipment, hand-held and high volume rollers, and wipers throughout
      the U.S. and, in some states, by aerial application equipment in
      forestry.  Roundup is nonselective and may be applied to undesirable
      species in four ways in the culture of desirable species: (1) Prior
      to the emergence of the following desirable species: alfalfa, edible
      beans, grasses for seed production, green or English peas, and
      turfgrasses.  (2) Prior to emergence or within (as a directed spray
      or spot treatment) a growing stand of the following desirable species:
      apples, asparagus, barley, citrus, cotton, corn, grapes, nut crops,
      cherries, oats, ornamentals, pears, sorghum (milo), soybeans,
      sugarcane, and wheat.  (3) Within established avocado groves. (4)
      Through selective equipment in cotton or soybeans.
           It may also be applied by conventional means or through selective
      equipment for general weed control in noncrop areas such as industrial,
      recreational, and public areas such as airports, ditch banks, dry
      ditches and canals, fencerows, golf courses, highways, industrial plant
      sites, rights-of-way, etc., and in farmstead weed control (56).

                                   I.  EFFICACY

      Weeds which can be effectively controlled by Roundup herbicide:

      1.  Annuals

          A.  Annual grasses                B.  Annual broadleaves

                Annual bluegrass                  Common lambsquarter
                Crabgrass species                 Common ragweed
                Downy brome                       Fleabane (Erigeron species)
                Panicum species                   Giant ragweed
                Field sandbur                     Kochia
                Foxtail species                   Pennsylvania smartweed
                Shattercane                       Prickly lettuce
                Volunteer wheat                   Redroot pigweed
                                                  Russian thistle
                                                  Smooth pigweed

      2.  Perennials

          A.  Perennial grasses                  B.  Perennial broadleaves

                Bermudagrass                           Canada thistle
                Kentucky bluegrass                     Common mullein
                  (Poa species)                        Curly dock
                Dallisgrass                            Field bindweed
                Fescue species                         Hemp dogbane
                Johnsongrass                           Milkweed (Asclepias
                Napiergrass                              species)
                Paragrass                              Silverleaf nightshade
                Quackgrass                             Swamp smartweed
                Wirestem Muhly (55a)

                             II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:  C3 H8 NO5 P (glyphosate); C6 H17 N2 O5 P
                          (glyphosate-mono(isopropylammonium)) (62).

      MOLECULAR WEIGHT:   169.1 (glyphosate); 228.2 (glyphosate-mono
                          (isopropylammonium)) (62).

      PHYSICAL STATE:     Colorless crystals (pure compound, zwitterion
                          structure) (62)

      ODOR:               None (pure chemical) (54)

      MELTING POINT:      200 C (pure compound) (62)

      VAPOR PRESSURE:     Negligible (pure chemical) (54)

      SOLUBILITY:         At 25 C 12 g/l water (pure compound);
                          glyphosate-isopropylammonium is very soluble
                          in water (62).

                          III.  HEALTH HAZARD INFORMATION





           A.  ACUTE TOXICITY

               DERMAL:  MLD = >7940 mg/kg (rabbit, glyphosate); >7940 mg/kg
                          (rabbit, Roundup formulation) (54).
                        Nonirritating (rabbit, glyphosate); mild irritant
                          (rabbit, Roundup formulation) (54).
                        LD50 = >5000 mg a.i./kg, 3750 mg a.e. (as salt)/kg
                          (rabbit) (62).

               ORAL:    LD50 = 4320 mg/kg (rat, glyphosate); 4900 mg/kg
                          (rat, Roundup formulation) (54).
                        LD50 = 5600 mg a.i./kg, 4050 mg a.e. (as salt)/
                          kg (rat) (62).

               INHALATION:  LC50 = 3.28 mg/l for 4 hour aerosol exposure,
                              slightly toxic (rat) (55b).
                            Rats exposed for 4 hours to a concentration of
                              12.2 mg/liter of air survived with no abnormal
                              reactions.  No relevant gross pathology was noted
                              when they were sacrificed and autopsied 10 days
                              later (Roundup formulation) (54).

               EYES:    (FHSA) Score = 18.4 on a scale of 110, moderately
                          irritating (rabbit) (55b).
                        Slightly irritating to rabbits' eyes (62).


          Technical material was fed to rats and dogs at dietary levels of
      200, 600, and 2000 ppm for 90 days.  No significant differences from
      control animals were observed in mean body weight, food consumption,
      behavioral reactions, mortality, hematology, blood chemistry, or
      urinalyses.  There were no relevant gross or histopathologic changes.
          Two-year feeding studies to rats and dogs and rat production
      studies at dietary levels of 30, 100, and 300 ppm have shown no adverse
      effects (54).
          Tests on the biologically active ingredient in this formulation
      (glyphosate) showed that glyphosate did not cause any mutagenic,
      carcinogenic, teratogenic (birth defects), adverse reproductive
      changes, or neurotoxic effects (55b).
          In 2-yr feeding trials on rats and dogs no ill-effect was observed
      at 300 mg/kg diet (highest dose treated) (62).

                        IV.  ENVIRONMENTAL  CONSIDERATIONS

          Toxicological investigations conducted with bobwhite quail, mallard
      ducks, honey bees, rainbow trout, bluegills, and other species of fish
      show that these species have an extremely high tolerance to glyphosate.

          Strong adsorption to soils is evidenced in part by low
      phytotoxicity produced by soil applications.  Glyphosate leaching is
      very low.

          Microbiological degradation is the major cause of decomposition of
      glyphosphate in soil.  Depending on soil and microfloral population
      types, varying rates of decomposition occur, producing for example,
      from 10 to 60% 14CO2 from glyphosate - C14 over growing season time
      periods or less.  Normally the half life is less than 60 days.

          Negligible loss from photodecomposition and/or volatilization.
      Glyphosate is relatively nonpersistent in soil and offers little or no
      preemergent activity; thus it appears that crops can be planted or
      seeded directly into treated areas following application.  Soil
      residues usually are near or below 10% of that applied within a growing
      season (54).

      Environmental Toxicity Information:

      96-hr TL50 Bluegill:  14 mg/l, slightly toxic
      96-hr TL50 Carp:  3.9 ppm, moderately toxic
      96-hr TL50 Trout:  11 mg/l, slightly toxic
      96-hr LC50 Catfish:  16 mg/l, slightly toxic
      96-hr LC50 Crayfish:  >1000 ppm, practically nontoxic
      96-hr LC50 Fathead minnow:  9.4 mg/l, moderately toxic
      48-hr LC50 Daphnia:  5.3 mg/l, moderately toxic

          Carp contained in a static pond were unaffected at any time during
      the 90-day observation period by exposure to an aerial application of
      Roundup herbicide at the intended use level.  Tissue residue analyses
      indicated that glyphosate will not bioaccumulate (55b).

          LC50 (8-d) for quail and ducks was >4640 mg a.i./kg diet.  LC50
      (96-hr) is: for trout 86 mg a.i./l, 8.2 mg a.e. (as salt)/kg; for
      bluegill 120 mg/l, 10.5 mg a.e. (as salt)/kg (62).


           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.

      KNOWN OR SUSPECTED ADVERSE EFFECTS:  Irritant to eyes and respiratory
      tract (25).

           SKIN CONTACT:  Wash contaminated skin with soap and water (25).

           INGESTION:     Ingestions of small amounts (less than 10 mg/kg
                          body weight) occurring less than an hour before
                          treatment, are probably best treated by:  Syrup of
                          Ipecac, followed by 1-2 glasses of water.  Dose for
                          adults and children over 12 years:  30 ml.  Dose
                          for children under 12 years:  15 ml (25).

           EYE CONTACT:   Flush contaminated eyes with copious amounts of
                          fresh water for 15 minutes (25).


      INGESTIONS of LARGE amounts (more than 10 mg/kg) occurring less than an
      hour before treatment, should probably be treated by gastric lavage:
      A.  INTUBATE stomach and ASPIRATE contents.
      B.  LAVAGE stomach with slurry of ACTIVATED CHARCOAL in 0.9% saline.
          Leave 30-50 gm activated charcoal in the stomach before withdrawing
      C.  SODIUM SULFATE, 0.25 gm/kg in tap water, as a cathartic.
          CAUTION:  Hydrocarbons (kerosene, petroleum distillates) are
                    included in some formulations of these chemicals.
                    Ingestion of very LARGE AMOUNTS may cause CNS depression.
                    In this case, IPECAC IS CONTRAINDICATED.  Also gastric
                    intubation incurs a risk of HYDROCARBON PNEUMONITIS.  For
                    this reason observe the following precautions:
                    (1)   If the victim is unconscious or obtunded and
                          facilities are at hand, insert an ENDOTRACHEAL TUBE
                          (cuffed, if available) prior to gastric intubation.
                    (2)   Keep victim's head BELOW LEVEL OF STOMACH during
                          intubation and lavage (Trendelenburg, or left
                          lateral decubitus, with head of table tipped
                          downward).  Keep victim's head turned to the left.
                    (3)   ASPIRATE PHARYNX as regularly as possible to remove
                          gagged or vomited stomach contents.
      INGESTIONS occurring MORE THAN an HOUR before treatment are probably
      best treated only by ACTIVATED CHARCOAL, 30-50 gm, and SODIUM or
      MAGNESIUM SULFATE, 0.25 gm/kg, as described above.
      There are no specific antidotes for these chemicals.  Because
      manifestations of toxicity do occasionally occur in peculiarly
      predisposed individuals, MAINTAIN CONTACT with victim for at least 72
      hours so that unexpected adverse effects can be treated promptly (25).

                        VI.  FIRE AND EXPLOSION INFORMATION

      GENERAL:  Flash Point (TCC):  >200 F.  Water-based formulation,
      Nonflammable, noncombustible.
      Special Firefighting Procedures:  None.
      Unusual Fire and Expolosion Hazards:  None (55b).

      EXTINGUISHER TYPE:  In case of fire, use water spray, foam, dry
      chemical or CO2 (55b).

                                VII.  COMPATIBILITY

          Tank mixtures with residual type herbicides, such as substituted
      ureas, triazines, or others may reduce activity of glyphosate.  Other
      combinations with foliage absorbed herbicides such as paraquat,
      dalapon, MSMA, phenoxy, or other hormone type herbicides may modify or
      lower action of glyphosphate.  Corrosive to iron and galvanized steel.
      Do not hold spray mixtures in galvanized or unlined steel tanks (except
      stainless) for extended periods.  Following application clean sprayer
      parts by flushing with water (54).

                            VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING: Formulations of glyphosate are quite stable under
      temperatures up to 140 F, however will freeze at -20 F, but will go
      back into solution upon thawing.  Does not require heated facilities.
      Handle with care, avoid contact with eyes, avoid spray drift to
      desirable vegetation.  Mix store, and apply glyphosate solutions in
      stainless steel, aluminum, fiberglass, plastic, or plastic-lined steel
      containers (54).

      PROTECTIVE CLOTHING:  During mixing or pouring operations or other
      activities in which eye contact with undiluted Roundup herbicide is
      likely to occur, splash goggles should be worn.
      In cases in which prolonged or repeated skin contact with Roundup
      herbicide may occur, long-sleeved shirt, long pants and rubber or
      plastic gloves are recommended.  Clothing soaked with Roundup solution
      should be promptly removed and laundered before reuse (55b).

      PROTECTIVE EQUIPMENT:  Respiratory protection is not required for
      normal use and handling.  During periods of abnormal exposure to heavy
      spray or mist, use a NIOSH approved dust/mist respirator (55b).

                       IX.  PROCEDURES FOR SPILLS AND LEAKS

                                  (800) 424-9300

          Open dumping is prohibited.

          This product (Roundup), spray mixture or rinsate that cannot be
      used or chemically reprocessed should be disposed of in a landfill
      approved for pesticides.

          Triple rinse container and offer for recycling, reconditioning, or
      disposal in approved landfill.

          Consult federal, state, or local disposal authorities for
      additional or alternative requirements.

          Avoid skin and eye contact.

          Soak up small amounts with absorbent clays (kitty litter, oil dri,

          Sweep or scoop up spilled material and dispose of in approved

          Wash down surfaces (floors, truck beds, streets, etc.) with
      detergent and water soluion (55b).

                               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.

      54.  Weed Science Society of America, Herbicide Handbook Committee.
               1979.  Herbicide handbook of the weed science society
               of America, 4th ed.  Weed Science Society of America,
               Champaign, IL.  479 pp.

      55a. Monsanto Agricultural Products Company.  1978.  Guide for
               Roundup herbicide.  St. Louis, MO.

      55b. Monsanto Company.  1982.  Material safety data:  Roundup
               herbicide.  St. Louis, MO.

      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.