United States
                             Environmental Protection
                             Agency
                     Office of Water
                     4601
            EPA811-F-95-0030-T
                   October 1995
                             National  Primary Drinking
                             Water Regulations
                             Endrin
  CHEMICAL/ PHYSICAL PROPERTIES

  CAS NUMBER: 72-20-8

  COLOR/ FORM/ODOR:
    Odorless white crystals

  M.P.: 200° C    B.P.: decomp. 245° C

  VAPOR PRESSURE: 2x10"7 mm Hg at 25° C

  OCTANOL/WATER PARTITION (Kow):
    Log Kow = 5.6(calc.)
DENSITY/SPEC. GRAV.:  1.7 at 20° C

SOLUBILITY: 0.2 mg/L of water; Slightly
   soluble in water

SOIL SORPTION COEFFICIENT:
  . Koc =34,000 (est); low mobility in soil

ODOR/TASTE THRESHOLDS:  N/A

BlOCONCENTRATION FACTOR:
   1335 to 10,000 in fish; expected to
   bioconcentrate in aquatic organisms.
HENRY'S LAW COEFFICIENT:
  4x1 Or7 atm-cu m/mole

TRADE NAMES/SYNONYMS:
  Nendrin; EN 57; Endrex; Endricol;
  Hexadrin; Mendrin; Oktanex; Com-
  pound 269; Hexachloroepoxy-
  octahydro-endo.endo-dimethano-
  naphthalene
DRINKING WATER STANDARDS              '
  MCLG:      0.002 mg/L
  MCL:       0.002 mg/L
  HAL(child):  1 - to 10-day: 0.02 mg/L
             Longer term: 0.003 mg/L

HEALTH EFFECTS SUMMARY
  Acute: EPA has found endrin to potentially cause the
following health effects from acute exposures at levels
above the MCL: tremors, labored breathing, mental con-
fusion, convulsions.
  Drinking water levels which are considered "safe" for
short-term exposures: For a 10-kg (22 Ib.) child consum-
ing 1 liter of water per day, upto a ten-day exposure to
0.02 mg/L or up to a 7-year exposure to 0.003 mg/L.
  Chronic:   Endrin has the  potential to cause the
following  health effects from  long-term exposures at
levels above the MCL: convulsions and damage to liver
tissue.
  Cancer: There is inadequate evidence to state whether
or not endrin has the potential to cause cancer from a
lifetime exposure  in drinking water.

USAGE PATTERNS
  Endrin is an aliphatic chlorinated insecticide which has
been used mainly on field crops such as cotton, maize,
sugarcane, rice, cereals, ornamentals, and other crops.
tt has also been used for grasshoppers in non-cropland
and to control voles and mice in orchards.
                  Once widely used in the US, most uses were cancelled
                in 1980. Production in 1980 was reported to be 100,000
                Ibs.

                RELEASE PATTERNS
                  Endrin's former source in the environment is from use
                as an insect, bird and  rat-killer. It has been used on
                agricultural crops, cotton seeds, control of birds on build-
                ings and mice in orchards. Its major use has been on
                cotton crops. The  U.S. EPA presently considers the
                pesticide cancelled.

                ENVIRONMENTAL FATE
                  Endrin is very persistent, but it is known to photode-
                grade to delta-ketoendrin (half-life 7 days - June). Endrin
                released to soils will persist for extremely long periods of
                time  (up to 14 yr  or more). Biodegradation may be
                enhanced somewhat in flooded soils or under anaerobic
                conditions. Its low water solubility and strong adsorption
                to soil makes leaching into groundwater unlikely. How-
                ever, the detection of endrin in  certain  groundwater
                samples suggest that leaching may be possible in some
                soils.
                  Endrin's low vapor pressure suggests only  limited
                evaporation from soil. However, several studies have
                suggested that moderate to extensive loss of endrin from
                soils and crops was due to evaporation. Runoff from rain
                or irrigation of particle-associated endrin will carry par-
                ticle-associated endrin to water systems
                  Endrin released to water systems will not hydrolyze or
                biodegrade. It will be subject to photoisomerization to
October 1995
         Technical Version
             Printed on Recycled Paper

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ketoendrin. It will extensively sorb to sediment. Evapora-
tion from water will not be significant.
  Fate of endrin in the atmosphere is unknown, but it
probably will be primarily associated with participate
matter and be removed mainly by rainout and dry depo-
sition.
  There is significant bioconcentration of endrin  in fish,
with BCFs of 1335-10,000 reported. In addition, there is
moderate to extensive bioconcentration in shellfish (BCF
of 500-1250) and in snails (BCF of 49,000).
  Monitoring data demonstrates that endrin continues to
be a contaminant in air, water, sediment, soil, fish, and
other aquatic organisms. Human exposure appears to
come mostly from food or occupational exposure.
                                                           OTHER REGULATORY INFORMATION
                                                           MONITORING:
                                                           FOR GROUND/SURFACE WATER SOURCES:
                                                             INITIAL FREQUENCY- 4 quarterly samples every 3 years
                                                             REPEAT FREQUENCY- If no detections during initial round:
                                                                           2 quarterly per year if serving >3300 persons;
                                                                           1 sample per 3 years for smaller systems
                                                           TRIGGERS - Return to Initial Freq. if detect at > 0.00001 mg/L
                                                                                     METHOD NUMBERS
                                                                                     505; 508; 508.1; 525.2
         ANALYSIS:
         REFERENCE SOURCE
         EPA 600/4-88-039


         TREATMENT:
         BEST AVAILABLE TECHNOLOGIES
         Granular Activated Charcoal
                                                           FOR ADDITIONAL INFORMATION:
                                                           * EPA can provide further regulatory and other general information:
                                                           • EPA Safe Drinking Water Hotline - 800/426-4791

                                                           4 Other sources of lexicological and environmental fate data include:
                                                           • Toxic Substance Control Act Information Line - 202/554-1404
                                                           • Toxics Release Inventory, National Library of Medicine - 3QM496-65
                                                           • Agency for Toxic Substances and Disease Registry - 404/639-6000
                                                           • National Pesticide Hotline - 800/858-7378
October 1995
Technical Version
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