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Physical/Chemical Parameters:Endrin


      PESTICIDE NAME: Endrin
      Trade name(s): Endrin
      Manufacturer(s): Shell International Chemical Co., Ltd.
                       London, England
      I.  Basic information
          A. Molecular structure: C12H8Cl6O
          B. Chemical name: 1,2,3,4,10,10-Hexachloro-6,7-epoxy-
      1,4,4a,5,6,7,8,8a-octahydro- endoa-5,8-dimethanonapthalene
          C. Derivatives: 6 metabolites
          D. Molecular weight: 379 g/mole
          E. Solubility in water: 0.23 mg/l
          F. Common physical appearance: emulsifiable concentrate, wettable
      powder, dust and dust concentrate
          G. Oral LD50(rat): 10 mg/kg
          H. Pesticide classification: chlorinated hydrocarbon insecticide
          I. Restricted use list (N.Y.): yes
             EPA priority pesticide list:  yes
          J. Crop use: No information available
      II. Text
           Endrin is an immobile, persistent organochlorine insecticide which
      is widely treated in the scientific literature.  It is strongly
      adsorbed in soils and desorption is difficult.  Endrin converts in soil
      to more stable compounds which are formed as early as 7d after
      application of the parent specie.  There is more rapid degradation of
      endrin under sterile conditions than in non-sterile soil and in flooded
      as opposed to non-flooded conditions.  The half-life of endrin has been
      estimated to be 4-8yrs.
      III. Soils information
           A. Degradation and transformation
           The degradation of endrin has been reported to be of both a
      chemical and a biological nature.  In flooded alluvial, laterite, clay
      loam, saline, and sandy soils, the endrin concentration declined
      rapidly in all but the sandy soil (possibly due to low organic
      matter).  At 55d, the endrin concentration in the soils other than the
      sandy was 5% of the original application. Additionally, it was found
      that degradation occurred at either negative or positive redox and that
      more rapid degradation was evidenced in sterile than in non-sterile
      soils, i.e., 30-40% residue in autoclaved soil after 55d.  From this it
      was concluded that degradation is both chemical and biological.  More
      metabolites were present in the non-sterile soil, a result of microbial
      decomposition.  If rice straw were added, degradation of endrin and its
      metabolites increased(2).  Another study found that endrin breakdown to
      metabolites occurred 7-25d after flooding the soil(3).
           The tables below present data concerning degradation and
      transformation of endrin in soil.  The reference is given in
      parentheses at the end of each title.
      Endrin-14C recovered, cpm x 104/20g soil, in various flooded soils(see
      incubation day zero for initial application)(2)
      Incub.         clay         red
       days          loam         loam       sandy
        0            68.8         58.3        67.5
       25            44.7         58.1        58.1
       55            23.4         20.2        41.5
      Endrin degradation in peanut and soybean cropped soils with a
      pre-application of 0.14ppm endrin and subsequent additions of 1,2 and 4
      lbs/A a.i.(1)
      AT PLANTING     Applic. Rate     Peas      Soybeans
                         1 lb/A      0.32ppm    0.47ppm
                         2           0.90       1.11
                         4           2.08       1.49
      AT HARVEST         1           0.23       0.17
      (5mo after         2           0.51       0.49
       applic.)          4           0.60       0.48
           B. Adsorption and transport
           Because the adsorption of endrin is strong, desorption is not
      extensive.  The tables below present data concerning adsorption of
      endrin.  The reference is given in parentheses at the end of each
      Adsorption of endrin in organic and sandy soils(5)
      Organic soil: 1min - 58%, 30min - 75%, 2hr - 87%, 4hr - 95%
      Sandy soil:          70           80         85         95
      Adsorption parameters of endrin in various soils(5)
              org.     sedim.     sl         sand
      l/n    1.08     0.99      1.12        1.03
       K     3404      258       112          58
      IV. References (*denotes key reference)
      *1.Dorough, H.W. and N.M. Randolph. 1967.
          Tex.Ag.Exp.Sta.Miscell.Publ. 854.
      *2.Gowda, T.K.S. and N. Sethunathan. 1976.  J.Ag.FoodChem. 24. 750-3.
       3.Gowda, T.K.S. and N. Sethunathan. 1977.  SoilSci. 124. 5-9.
       4.Kahn, S.U. 1980.  Pesticides in the Soil Environment.
          Amsterdam:Elsevier Press.
      *5.Sharom, M.S., J.R.W. Miles, C.R. Harris, F.L. McEwen. 1980. Water
          Research. 14. 1095-1100.