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methoxychlor (Marlate)


      CHEMICAL NAME:      2,2-bis(p-methoxyphenyl)-1,1,1-trichloroethane (56)


      TRADE NAME(S):      Marlate, Flo Pro Mc Seed Protectant, Chemform (dis-
                          continued), Moxie (discontinued), Prentox, Double-M

      FORMULATION(S):     Wettable powders, emulsifiable concentrates, oil
                          solutions, dusts, flowables (56).

      TYPE:               Organochlorine insecticide

      BASIC PRODUCER(S):  Hopkins Agricultural Chemical Co.
                          P.O. Box 7532
                          Madison, WI 53707

                          Kincaid Enterprises, Inc.
                          P.O. Box 671
                          Nitro, WV 25143

                          Prentiss Drug and Chemical Co., Inc.
                          21 Vernon St.
                          CB 2000
                          Floral Park, NY 11001

      STATUS:             General use

      PRINCIPAL USES:  Widely used because of its long residual action
      against many species of insects and its low toxicity to humans and
      warm-blooded animals.  For control of certain insect pests on fruit and
      shade trees, vegetables, dairy and beef cattle, home gardens, and
      around farm buildings (except poultry houses).  (An excellent
      replacement for DDT where application may constitute a hazard to
      warm-blooded animals or susceptible plants.  It is rarely phytotoxic,
      and injury is usually negligible even on DDT-susceptible crops such as
      cucurbits) (56).

                                   I.  EFFICACY

      Important Pests Controlled: Houseflies, lice, ticks, weevils, stored
      grain beetles, leafhoppers, Japanese beetles, armyworms, codling moths,
      plum curculio, spittlebugs, scale (crawlers), lygus bugs, and many
      others (8a).
           Aphids and mites are not controlled (8a).

                             II.  PHYSICAL PROPERTIES

      MOLECULAR FORMULA:  C16 H15 Cl3 O2 (62)

      MOLECULAR WEIGHT:   345.7 (62)

      PHYSICAL STATE:     Colorless crystals (pure compound); gray powder
                          (technical product, contains 88% or more of
                          methoxychlor and 12% or less of related isomers)

      ODOR:               Pungent (34c)

      MELTING POINT:      89 C (pure ); 77 C (setting point, technical product)

      SOLUBILITY:         0.1 mg/l water at 25 C (technical product) (62).

                          III.  HEALTH HAZARD INFORMATION

      OSHA STANDARD:  15 mg/m3 averaged over an 8-hr. work shift (14).

      NIOSH RECOMMENDED LIMIT:  None established

      ACGIH RECOMMENDED LIMIT:  TWA (Time Weighted Average): 10 mg/m3 (15c).


           A.  ACUTE TOXICITY

               DERMAL:  Application to skin of rabbits of 2820 mg (in dimethyl
                        sulfoxide) produced no symptom (62).

               ORAL:    LD50 = 6000 mg tech./kg (rat) (62)


           In 1-yr feeding trials no toxic effect was observed in dogs
      receiving 300 mg/kg daily; in 2-yr trials in rats there was no effect at
      200 mg/kg diet, but some reduction in growth occurred at 1600 mg/kg diet
           Lehman (1952) found that a dietary level of 100 ppm (equivalent to
      350 mg/man/day) for two years was the lowest dosage producing no
      symptoms, although tissue change was absent at 200 ppm and appeared only
      at levels of 500 ppm or higher.  Tegeris and associates (1966) found that
      dogs fed 1 gm/kg per day for 6 months lost weight.  At 2 gm/kg most
      animals died within nine weeks.  Pigs were more resistant (15b).
           Although some liver tumors were observed in rats fed up to 2000 ppm
      in the diet, it is not possible to evaluate adequately the
      carcinogenicity of methoxychlor due to inadequate reporting of these
      data; three other feeding studies produced no evidence of carcinogenesis.
      In mice given 5 mg orally over 3 days and in rats given 20 mg there was a
      uterotrophic effect manifested as a marked increase in weight of the
      uterus (14).

                        IV.  ENVIRONMENTAL  CONSIDERATIONS

           Little or no hazard to birds, fish and beneficial insects.
      Relatively nonhazardous to honey bees.  Biological magnification
      unlikely.  Considered to be nonphytotoxic (1).
           Toxic to fish and bees (8a).

      Approximate Residual Period:  Several weeks on plant surfaces; over 1
      year on bark; long residual in soil and water (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:  Bathe and shampoo the victim vigorously with soap
      and water if skin and hair have been contaminated (25).

           INGESTION:  If victim is alert and gag reflex is not depressed,
      give Syrup of Ipecac to induce vomiting (adults and children 12 years
      and older: 30 ml; children under 12: 15 ml), followed by 1-2 glasses
      of water (25).

           INHALATION:  If a person breathes in large amounts of methoxychlor,
      move the exposed person to fresh air at once (14).

           EYE CONTACT:  Wash with lots of water for at least 15 minutes.
      Seek medical attention, if necessary (34c).


      Adult dosage:  5-10 mg (1-2 ml) slowly, intravenously (no faster than
      one ml per minute) or give total dose intramuscularly (deep).  Repeat
      in 2-4 hours if needed.
      Dosage for children under 6 years or 23 kg in weight:  0.1 mg/kg (0.02
      ml/kg) intravenously, no faster than half the total dose per minute, or
      give total dose intramuscularly (deep).  Repeat in 2-4 hours if needed.
      Persons suffering SEVERE PROTRACTED CONVULSIONS may require additional
      anticonvulsant medication.  Agents that have been used successfully in
      the past are pentobarbital (Numbutal (TM)), phenytoin (Dilantin (TM)),
      thiopental (Pentothal (TM)), and succinylcholine (Anectine (TM)).
      If the victim is NOT FULLY ALERT, empty the stomach immediately by
      INTUBATION, ASPIRATION, and LAVAGE, using isotonic saline or 5% sodium
      bicarbonate.  Because many pesticides are dissolved in petroleum
      distillates, emesis and intubation of the stomach involve a serious
      risk that solvent will be aspirated, leading to chemical pneumonitis.
      DO NOT give epinephrine or other adrenergic amines, because of the
      enhanced myocardial irritability induced by chlorinated hydrocarbons

                        VI.  FIRE AND EXPLOSION INFORMATION

           Nonflammable (34c).

                                VII.  COMPATIBILITY

           Generally compatible but do not mix with lime or alkaline materials
      (1).  Reacts with strong oxidizers such as chlorine and permanganates

                            VIII.  PROTECTIVE MEASURES

      STORAGE AND HANDLING:  Protect containers from damage.  Store in cool,
      dry area away from fire hazard and out of direct sunlight (34c).

      PROTECTIVE CLOTHING:  Wear splash-proof goggles and impervious gloves,
      apron and boots (34c).

      PROTECTIVE EQUIPMENT:  For levels up to 150 mg/m3 use a chemical
      cartridge respirator with dust, mist and fume filter, including
      pesticide respirator meeting these requirements, a supplied-air
      respirator, or self-contained breathing apparatus.
             For levels up to 750 mg/m3 use the above with full facepiece or
      gas mask with organic vapor canister with dust, fume and mist filter,
      including pesticide respirators meeting these requirements.  For levels
      up to 7500 mg/m3 use a powered air-purifying respirator with
      high-efficiency filter and organic vapor cartridge including pesticide
      respirators meeting these requirements, or a Type C supplied-air
      respirator in a positive pressure or continuous flow mode (34c).

                       IX.  PROCEDURES FOR SPILLS AND LEAKS

                                  (800) 424-9300

           Persons not wearing protective equipment and clothing should be
      restricted from areas of spills until cleanup has been completed.

      If methoxychlor is spilled, the following steps should be taken:

      1.   Ventilate area of spill.
      2.   Collect spilled material in the most convenient and safe manner
           and deposit in sealed containers for reclamation, or for disposal
           in a secured sanitary landfill.  Liquid containing methoxychlor
           should be absorbed in vermiculite, dry sand, earth, or a similar

      Waste disposal method:  Methoxychlor may be disposed of in sealed
      containers in a secured sanitary landfill (14).

                               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.

      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.

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

      34c. New York State Department of Health, Bureau of Toxic Substances
               Management.  1981.  Chemical fact sheet:  methoxychlor.
               Albany, NY.

      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.