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EPN Chemical Profile 1/88


      CHEMICAL NAME:      Ethyl p-nitrophenyl thionobenzenephosphonate (31a)


      TRADE NAME(S):      EPN (56)

      FORMULATION(S):     Wettable powders, granules, emulsifiable formulations
                          5 lb. EPN (5 lbs./gal.) (56)

      TYPE:               Organophosphate insecticide-miticide

      BASIC PRODUCER(S):  E.I. du Pont de Nemours and Co., Inc.
                          Biochemical Dept.
                          DuPont Building
                          Wilmington, DE 19898

      STATUS:  Restricted use.  RPAR issued 9/19/79; criteria possibly met or
      exceeded: neurotoxicity.  Final Notice of Determination and Decision
      Document forwarded to Acting AA on June 30, 1983 (22).

No Special Review for EPN

    On July 21, 1987, EPA issued a proposed decision not to initiate a
special review of EPN.  The proposed decision was based on the fact that
there were no remaining viable registrations for EPN.  Since EPA received no
comments on the proposed decision, the Agency has announced not to initiate a
special review.  All registrations of technical EPN and formulated products
containing EPN have been voluntarily cancelled.  The sale and use of existing
stocks will be allowed until August 31, 1988.  After that date all remaining
stocks must be disposed of as permitted by state law (Federal Register,

      PRINCIPAL USES:  For control of insects such as European corn borer,
      rice stem borer, bollworm, tobacco budworm, and boll weevil (56).

                                    I.  EFFICACY

      Important Pests Controlled: Rice stem borer, boll weevils, Oriental fruit
      moth, cotton bollworms, plum curculio, fruit moths, peachtree borers,
      mites, European cornborers, scale, budmoths, leafrollers, codling moths,
      pear psylla, aphids, thrips, armyworms, leaf miners, Mexican bean
      beetles, and many others (8a).
           Acts similar to parathion only it is somewhat more persistant (8a).

                             II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:   C14 H14 NO4 P5 (62)

      MOLECULAR WEIGHT:    323.3 (62)

      PHYSICAL STATE:      Light yellow crystalline powder (pure compound);
                           dark amber-colored liquid (technical product) (62).

      MELTING POINT:       36 C (pure compound) (62)

      VAPOR PRESSURE:      126 uPa at 25 C (pure compound) (62)

      SOLUBILITY:          Practically insoluble in water (pure compound) (62)

                           III.  HEALTH HAZARD INFORMATION

      OSHA STANDARD:  0.5 mg/m3 averaged over an 8-hour work shift (14)

      NIOSH RECOMMENDED LIMIT:  None established

      ACGIH RECOMMENDED LIMIT:  TWA (Time Weighted Average) = 0.5 mg/m3;
                                STEL (Short Term Exposure Level) = 2 mg/m3
                                (deleted); skin notation (15c).


           A.  ACUTE TOXICITY

               DERMAL:  LD50 = 230 mg/kg (male rat), 25 mg/kg (female rat)
                        LD50 = 420 mg/kg (rabbit) (56)
                        LD50 = 90-150 mg/kg (female rabbit); 30-50 mg/kg
                          (male rabbit) (31a).
                        Moderate to no skin irritation (31a)

               ORAL:    LD50 = 33-42 mg/kg (male rat); 14 mg/kg (female rat);
                          50-100 mg/kg (mouse); all dogs tested survived at 20
                          mg/kg, all were killed by 45 mg/kg (62).

               INHALATION:  LC50 = 0.076 mg/l (male rat); 0.024 mg/l
                            (female rat) (31a).

               EYES:    When treated with 0.1 ml of undiluted 44.8% liquid
                        formulation, unwashed eyes (rabbit) had moderate
                        conjunctival irritation and mild corneal opacity.
                        In all washed eyes the compound caused transient mild
                        conjunctival irritation and transient slight corneal
                        opacity.  All eyes were normal within 2-7 days (31a).


           In 2-year feeding studies with rats, 75 ppm was a no-effect level
      for females and 150 ppm a no-effect level for males; highest levels fed
      (225 ppm for females and 450 ppm for males) retarded growth only.  EPN
      was not stored in vital organs or in depot fat.  In one-year studies
      with dogs (male and female), 2 mg/kg/day was a no-effect level.  In a
      21 month hen neurotoxicity study, no clinical signs of delayed
      neurotoxicity were seen in hens fed 18 ppm.  Delayed neurotoxicity was
      seen at 54 ppm.
           Ames Mutagenicity Study:  Negative.
           6 mg of EPN per day fed to human volunteers for 47 days produced
      no effects.  Daily dose of 9 mg for 56 days produced reversible
      inhibition of blood cholinesterase.  No neurotoxic effects were
      reported (31a).

                         IV.  ENVIRONMENTAL CONSIDERATIONS

           Moderately hazardous to birds, fish, and beneficial insects.
      Hazardous to honey bees.  Biological magnification unlikely.  Injurious
      to McIntosh and related varieties of apples (1).

      Rainbow Trout                LC50 (96-hr. exposure) = 190 ppb
      Bluegill Sunfish             LC50 (96-hr. exposure) =  80 ppb
      Daphnia magna                LC50 (48-hr. exposure) = 320 ppb
      Bobwhite Quail               LC50 (8-day feeding)   = 437 ppm
      Mallard Duck                 LC50 (8-day feeding)   = 294 ppm

      Bobwhite Quail               LD50 = 220 mg/kg
      Ringnecked Pheasant          LD50 = 165 mg/kg

           EPN  showed little tendency to leach.  Other evidence shows
      ultraviolet degradation of EPN, which probably contributes to its rapid
      environmental disappearance (31a).

      Approximate Residual Period:  3 weeks on plants; 80 days 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.


           Symptoms of acute poisoning develop during exposure or within 12
      hours (usually within four hours) of contact.  HEADACHE, DIZZINESS,
      CRAMPS, DIARRHEA, and SWEATING are common early symptoms.  Blurred or
      dark vision, confusion, tightness in the chest, wheezing, productive
      cough, and PULMONARY EDEMA may occur.  Incontinence, unconsciousness
      and convulsions indicate very severe poisoning.  SLOW HEARTBEAT,
      salivation, and tearing are common.  TOXIC PSYCHOSIS, with manic or
      bizarre behavior, has led to misdiagnosis of acute alcoholism.  Slowing
      of the heartbeat may rarely progress to complete sinus arrest.
      RESPIRATORY DEPRESSION may be fatal.  Continuing daily absorption of
      organophosphate at intermediate dosage may cause an INFLUENZA-LIKE
      ILLNESS characterized by weakness, anorexia, and malaise (25).

           SKIN CONTACT:  Bathe and shampoo victim with soap and water if
      there is any chance that skin and hair are contaminated (25).

           INGESTION:  If victim is alert and respiration is not depressed,
      give Syrup of Ipecac, followed by 1-2 glasses of water to induce vomting.
      Adults (12 years and over): 30 ml; children: 15 ml (25).

           INHALATION:  Remove from exposure and have patient lie down and
      keep quiet.  If patient is not breathing, start artificial respiration
      immediately.  Never give anything by mouth to an unconscious person

           EYE CONTACT:  Flush with water for 15 minutes and get medical
      attention (31a).


      Administer ATROPINE SULFTE intravenously, or intramuscularly, if IV
      injection is not possible.
      In MODERATELY SEVERE poisoning:  Adult dosage:  0.4-2.0 mg repeated
      every 15 minutes until atropinization is achieved:  tachycardia (pulse
      of 140 per minute), flushing, dry mouth, dilated pupils.  Maintain
      atropinization by repeated doses for 2-12 hours or longer depending on
      severity of poisoning.
      Dosage for children under 12 years:  0.05 mg/kg body weight, repeated
      every 15 minutes until atropinization is achieved.  Maintain
      atropinization with repeated dosage of 0.02-0.05 mg/kg.
      SEVERELY POISONED individuals may exhibit remarkable tolernce to
      atropine; two or more times the dosages suggested above may be needed.
      Administer PRALIDOXIME (Protopam (TM)-Ayerst, 2-PAM) in cases of severe
      poisoning in which respiratory depression, muscle weakness and
      twitchings are severe.
      Adult dosage:  1.0 gm intravenously at no more than 0.5 gm per minute.
      Child's dose (under 12 years):  20-50 mg/kg (depending on severity of
      poisoning) intravenously, injecting no more than half the total dose
      per minute.
      Dosage of pralidoxime may be repeated in 1-2 hours, then at 10-12 hour
      intervals if needed.  In very severe poisonings, dosage rates may be
      doubled (25).

                         VI.  FIRE AND EXPLOSION INFORMATION

           To be developed.

                               VII.  COMPATIBILITY

           Generally compatible except with Bordeaux and zinc-lime mixtures

                            VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING:  May be fatal if swallowed.  Poisonous if inhaled.
      Extremely hazardous by skin contact.  Rapidly absorbed through skin.
      Repeated exposure may, without symptoms, be increasingly hazardous.  Do
      not breathe vapor, do not get in eyes, on skin, on clothing.  Use with
      adequate ventilation.  Keep away from heat and open flame.  Keep
      container closed.  Store at 65-100 F (56).

      PROTECTIVE CLOTHING:  Wear clean heavy natural rubber gloves, rubber
      boots, and clean waterproof or freshly laundered protective clothing
      (coveralls, cap).  Destroy and replace gloves frequently (31a).

      PROTECTIVE EQUIPMENT:  When mixing or otherwise handling, wear goggles
      and a pesticide respirator jointly approved by the Mining Enforcement
      and Safety Administration and by NIOSH (31a).

                       IX.  PROCEDURES FOR SPILLS AND LEAKS

                      IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
                                   (800) 424-9300

           In case of spillage, cover with an absorbent such as soda ash,
      lime, clay, or sawdust.  Sweep up and bury.  Wash area thoroughly with
      strong lye solution; then flush with water (31a).

                               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.

      14.  U. S. Department of Health and Human Services, National Institute
               for Occuptational Safety and Health.  1981.  Occupational
               health guidelines for chemical hazards.  F. W. Mackinson, R.
               S. Stricoff, L. J. Partridge, Jr., and A. D. Little, Inc.,
               eds.  DHHS (NIOSH) Publ. No. 81-123.  Washington, DC.

      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.

      22.  U.S. Environmental Protection Agency, Office of Pesticide
               Programs.  1983.  June 1983 status report on rebuttable
               presumption against registration (RPAR) or special review
               process, registration standards and the data call in
               programs.  Washington, DC.  45 pp.

      25.  Morgan, D.P.  1982.  Recognition and management of pesticide
               poisonings, 3rd ed.  U.S. Environmental Protection Agency,
               Washington, DC.  120 pp.

      31a. E. I. du Pont de Nemours and Co., Inc.  1983.  Technical data
               sheet for EPN.  Wilmington, DE.

      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.