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pronamide (Kerb) Herbicide Profile 4/86

                        CHEMICAL FACT SHEET FOR:
                      1.  DESCRIPTION OF CHEMICAL
- Generic Name:  3,5-dichloro-N(1,1-dimethyl-2-propynyl)benzamide or
- Common Name:  pronamide (WSSA), RH-315
- Trade Name:  Kerb
- EPA Shaughnessy Code:  101701
- Chemical Abstracts Service (CAS) Number:  23950-58-5
- Year of Initial Registration:  1972
- Pesticide Type:  herbicide
- Chemical Family:  substituted benzamide
- U.S. and Foreign Producers:  Rohm and Haas
                     2.  USE PATTERNS AND FORMULATIONS
- Application sites:  Alfalfa, apples, globe artichokes, birdsfoot
  trefoil, blackberries, blueberries, cherries, clover, crown vetch,
  endive, grapes, lettuce, nectarines, peaches, pears, plums, rasp-
  berries, sainfoin, azalea, Douglas fir, fir, forsythia, holly,
  juniper, pine, rhododendron, yew, Christmas tree plantations,
  bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass.
- Types of formulations:  94% active ingredient techical grade,
  50% formulation intermediate, and 50% wettable powder.  Less than
  or equal to 1% granular formulations mixed with fertilizer end-use
- Types and methods of application:  End-use product is applied
  preplant, preemergence, or early postemergence by ground spray,
  incorporation, or aerial application.  Hand spray application is
  limited to ornamentals and nursery stock.
- Application rates:  0.5 to 4.0 lbs. a.i./A, depending on crop and
  weed problem.
- Usual carrier:  Water
                         3.  SCIENCE FINDINGS
Chemical Characteristics
- Physical state:  Crystalline solid
- Color: White
- Melting point: 155-156  degrees C
- Specific gravity: 0.48 gm/cc
- Solubility:
    Solvent                       ppm at 25 degrees C
      Dimethyl sulfoxide                  33
      Dimethyl formamide                  33
      Mesityl oxide                       20
      Isophorone                          20
      Methyl ethyl ketone                 20
      Cyclohexanone                       20
      Methanol                            15
      Isopropanol                         15
      Chlorobenzene                       12
      Butyl cellosolve                    10
      Xylene                              10
      Acetonitrile                        10
      Kerosene                            10
      Nitrobenzene                         5
      Ethylene dichloride                  5
      Water                               15
- Vapor pressure:  8.50 x 10(-5) Torr at 25 degrees C
- Stability:  Considered relatively stable
Toxicological Characteristics
- Acute effects:
  - Acute oral toxicity (rat):  16,000 (10,666-24,000) mg/kg,
    Toxicity Category IV
  - Acute dermal toxicity (rabbit):  Greater than 10 g/kg, Toxicity
    Category III
  - Acute inhalation toxicity (rat):  Greater than 3.2 mg/L,
    Toxicity Category III
  - Primary eye irritation (rabbit):  Slight eye irritant, Toxicity
    Category III
  - Primary skin irritation (rabbit):  Not a primary dermal irritant,
    Toxicity Category IV
  - Dermal sensitization (guinea pig):  Technical material is not a
    skin sensitizer, Toxicity Category IV.
- Subchronic effects:
  - Feeding study (dog):  Lowest effect level (LEL) is 4050 ppm
    (approximately 90 mg/kg/day).  NOEL is 1350 ppm (approximately
    30 mg/kg/day).
- Chronic effects:
- Chronic feeding (rat):  NOEL is 300 ppm (highest dose tested)
  (15 mg/kg)
  - Chronic feeding (dog):  NOEL is 7.5 mg/kg
  - Teratology (rabbits):  Maternal NOEL 5 mg/kg/day; LOEL 20 mg/kg/
    day; developmental LOEL 80 mg/kg/day; NOEL 20 mg/kg/day.
  - Oncogenicity (mice):  Positive
- Major routes of exposure:  Mixers and applicators would be expected
  to receive the most exposure via skin contact.
Physiological and Biochemical Behavioral Characteristics
- Foliar absorption:  To obtain activity, pronamide must move into
  the root zone of the weeds.  Little activity is obtained from
  foliar contact alone.
- Translocation:  Pronamide is readily absorbed by plants through
  the root system, translocated upward, and distributed into the
  entire plant.  The degree of translocation from leaf absorption
   is not appreciable.
- Mechanism of pesticidal action:  Pronamide appears to act as a
  cell division inhibitor.  Its main activity is against root
  development in germinating seeds or young seedlings, or, in the
  case of perennial grasses, against both root and vegetative bud
  development.  Pronamide is taken up by the roots and needs to be
  carried into the root zone by rainfall, irrigation, or incorporation.
Environmental Characteristics
- Available data are insufficient to fully assess the environmental
  fate of pronamide.  Pronamide is stable to hydrolysis at pH 4.7-8.8.
Ecological Characteristics
- Results of studies indicate that pronamide is practically nontoxic
  to birds, mammals, and fish, and possibly as much as moderately
  toxic to aquatic invertebrates.  These results are:
  - Aquatic invertebrate toxicity (Daphnia magna):  Greater than
    5.6 ppm (no more than moderate toxicity)
  - Avian acute toxicity (Japanese quail):  8,700 mg/kg (practically
  - Avian acute toxicity (mallard duck):  20,000 mg/kg (practically
  - Avian 8-day dietary toxicity (mallard duck):  Greater than 10,000
    ppm (practically nontoxic)
  - Avian 8-day dietary toxicity (bobwhite quail):  Greater than
    10,000 ppm (practically nontoxic)
  - Avian dietary toxicity (bobwhite quail):  Greater than 4,000 ppm
    (practically nontoxic)
  - Avian subacute toxicity (bobwhite quail):  Greater than 30 ppm
    (300 ppm was highest dose tested, and no deaths occurred;
    therefore, no toxicity level could be determined.)
  - 96-hour acute fish toxicity:  bluegill, >100 ppm; rainbow trout,
    72 (47-110) ppm; goldfish, 350 (312-392) ppm; guppy, 150 (113-
    200) ppm; catfish, <500 ppm but 200 ppm.  Practically nontoxic
    to warmwater fish, slightly toxic to coldwater fish.
Tolerance Assessment
- List of crops and tolerances (40 CFR 180.317):
  Commodity                          Tolerance (ppm)
  Alfalfa, fresh                        10.0
  Alfalfa, forage                       10.0
  Alfalfa, hay                          10.0
  Apples                                 0.1
  Artichokes                             0.1
  Blackberries                           0.05
  Blueberries                            0.05
  Boysenberries                          0.05
  Cattle, fat                            0.02
  Cattle, kidney                         0.2
  Cattle, liver                          0.2
  Cattle, meat byproducts (except        0.02
    kidney and liver)
  Cattle, meat                           0.02
  Cherries                               0.1
  Clover                                 5.0
  Crown vetch                            5.0
  Eggs                                   0.02
  Endive (escarole)                      2.0
  Goats, fat                             0.02
  Goats, kidney                          0.2
  Goats, liver                           0.2
  Goats, MBYP (except kidney and         0.02
  Goats, meat                            0.02
  Grapes                                 0.1
  Hogs, fat                              0.02
  Hogs, kidney                           0.2
  Hogs, liver                            0.2
  Hogs, MBYP (except kidney and          0.02
  Hogs, meat                             0.02
  Horses, fat                            0.02
  Horses, kidney                         0.2
  Horses, liver                          0.2
  Horses, MBYP (except kidney and        0.02
  Horses, meat                           0.02
  Lettuce                                1.0
  Milk                                   0.02
  Nectarines                             0.1
  Peaches                                0.1
  Pears                                  0.1
  Plums                                  0.1
  Poultry, fat                           0.02
  Poultry, kidney                        0.2
  Poultry, liver                         0.2
  Poultry, MBYP (except kidney and       0.02
  Poultry, meat                          0.02
  Raspberries                            0.05
  Sainfoin                               5.0
  Sheep, fat                             0.02
  Sheep, kidney                          0.2
  Sheep liver                            0.2
  Sheep MBYP (except kidney and          0.02
  Sheep, meat                            0.02
  Trefoil                                5.0
- Results of tolerance assessment:  The Provisional Acceptable Daily
  Intake (PADI) for pronamide was based on the NOEL of 7.50 mg/kg in
  the 2-year dog study.  It should be noted that this PADI is based
  on systemic toxicity (non-oncogenic).  The current PADI is 0.0750
  mg/kg/day, and the current published tolerance for pronamide has a
  calculated Total Maximum Residue Concentration (TMRC) of 0.0409
  mg/day (1.5 kg diet).  The percentage of PADI utilized is 0.91%.
Summary Science Statement
- Pronamide has been found to be oncogenic in male mice and has been
  tentatively classified as a Group C oncogen (possible human
  carcinogen), pending consideration of additional data.  Acute toxicity
  studies indicate Toxicity Category III.  Pronamide is practically
  nontoxic to birds, mammals, and fish, and possibly as much as
  moderately toxic to aquatic invertebrates.  Available data are
  insufficient to fully assess the environmental fate of pronamide.
- Use classification:  Wettable powder end-use products are being
  classified as restricted use pesticides.  Wettable powder formulations
  of pronamide pose risks, through dermal exposure, to mixers
  and applicators, which can be reduced to an acceptable level by
  requiring that pronamide only be applied by certified applicators.
- Unique label warning statements:
  - Manufacturing-use products:
    - Caution:  Harmful if absorbed through the skin or inhaled.
      Causes moderate eye irritation.  Avoid contact with the skin,
      eyes, or clothing.  Avoid breathing dust.  Wash thoroughly with
      soap and water after handling.  Remove contaminated clothing
      and wash before reuse.
    - Do not discharge effluent containing this product into lakes,
      streams, ponds, estuaries, oceans, or public water unless this
      product is specifically identified and addressed in an NPDES
      permit.  Do not discharge effluent containing this product into
      sewer systems without previously notifying the sewage treatment
      plant authority.  For guidance, contact your State Water Board
      or Regional Office of the EPA.
  - All end-use products:
    - General precautions:  Avoid contact with eyes, skin, or clothing.
    - Protective clothing:  When mixing, loading, or applying this
      product, wear mid-forearm, waterproof gloves, long-sleeved
      shirt and long pants, preferably one piece (coveralls).
      Hand-spray or hand-spreaders also require the use of waterproof
      boots or shoe coverings.  Wash non-disposable gloves, boots,
      and shoe coverings thoroughly with soap and water before
    - If water-soluble packaging is used, mixers and loaders are
      exempted from protective clothing requirements.
    - Protective clothing/equipment is not needed during application
      if an enclosed tractor cab with filtered air supply or enclosed
      cockpit is used.
    - Any article of clothing worn while handling product must be
      cleaned before reusing.  Clothing should be laundered separately
      from household articles.  Clothing which has been drenched or
      heavily contaminated should be disposed of in accordance with
      state or local regulations.
    - Do not apply directly to water.  Do not contaminate water by
      cleaning of equipment or disposal of wastes.
    - Crops other than those on which pronamide may be applied may
      not be planted in pronamide-treated soil.
    - Hand-spray applications of pronamide can be made only to orna-
      mentals and nursery stock.
- All wettable powder end-use products:  These products must be packaged
  in water-soluble packaging and bear the following statements:
  - RESTRICTED USE PESTICIDE.  Because pronamide has produced tumors in
    laboratory animals, this product is for retail sale to and use only
    by certified applicators or persons under their direct supervision,
    and only for those uses covered by the certified applicator's
  - Dilution instructions:  The enclosed pouches of this product are
    water-soluble.  Do not allow pouches to become wet before adding
    them to the spray tank.  Do not handle the pouches with wet hands or
    gloves.  Always reseal overwrap bag to protect remaining unused
    pouches.  Do not remove water-soluble pouches from overwrap except
    to add directly to the spray tank.  Add the required number of un-
    opened pouches as determined by the dosage recommendations into the
    spray tank with agitation.  Depending on the water temperature and
    the degree of agitation, the pouches should dissolve completely
    within approximately five minutes from     the time they are added
    to the water.
- All granular end-use products:  Site treated with this product must be
  thoroughly watered after application.
                      5.  SUMMARY OF MAJOR DATA GAPS
Date Required                               Due Date (after
                                          issuance of Standard)
- Chronic toxicity (rodent)                            50 months
- Oncogenicity (rat)                                   50 months
- Teratogenicity (rat)                                 15 months
- Reproduction (rat)                                   39 months
- Mutagenicity - gene mutation                          9 months
- Mutagenicity - structural chromosomal                12 months
- Mutagenicity - other genotoxic effects               12 months
- Special testing - general metabolism                 24 months
- Special testing - dermal penetration                 12 months
Environmental fate                                   9-39 months
Residue chemistry                                  January, 1988
                  6.  CONTACT PERSON AT EPA
Robert J. Taylor (PM-25)
U.S. EPA, TS-767C
401 M Street S.W.
Washington, DC  20460