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         ATE
U ALITY
          ADVISORY
         ENDOSULFAN  SULFATE
        Criteria and  Standards  Division
             i  Water Regulations and  Standards
                  United  States
          EInviranmental Protection Rgency
                MRRCH  1 9 8 G

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                           WATER QUALITY ADVISORY
                               Number  4 .

                            ENDOSULFAN SULFATE

                     Criteria  and Standards  Division
                Office of Water Regulations  and Standards
             United States Environmental Protection Agency


      The  advisory concentration for Endosulfan Sulfate in ambient water
for the protection  of  freshwater  aquatic life is estimated to  be  0.056
ug/L.  The  advisory concentration for the protection of saltwater
aquatic organisms is  estimated to be   0.0087 ug/L. Care should be
taken in the application  of this  advisory,  with  consideration  of its
derivation, as  stated in  the  attached support document.

    A value given to  protect  aquatic  life can be derived  from  no
observed effect levels (NOEL),  the  lowest concentration  found  in the
data which has been observed  to cause acute or chronic toxicity or
other experimental  data which may be  applicable.  When there is no
valid experimental  evidence,  a value may be derived from a model which
uses structure-activity relationships (SAR) as its basis. The  advisory
concentrations should  be  used with  caution, since they are  derived
from minimal experimental evidence,  or in the case of SAR derived
values, no data on  the specific chemical.

    The advisory  concentration for  Endosulfan Sulfate  in  ambient water
for the protection  of  human health  is estimated  to  be  74  ug/L, based
on data and information which are available to U.S.  EPA. Care  should
be taken in the application of this advisory, with  consideration of
its derivation, as  stated in  the attached  support document.

    An advisory concentration can be  derived  from a number of  sources:
The Office of Drinking Water Health Effects Advisories; Acceptable
Daily Intake(ADI)  values  from EPA;  Office of  Pesticides and Toxic
Substances risk assessments;  Carcinogen Assessment  Group(CAG)  cancer
risk  estimates; risk estimates derived  from the  open literature; or
other sources which will  be given in the support document.  The
advisory concentrations derived from  these  sources will vary in
confidence and usefulness, based on the amount and quality of  data
used as well as the assumptions behind the  original  estimates. The
user  is advised to  read the background  information carefully to
determine the strengths or deficiencies of the values given in the
advisory.
                     U.S. Environmental Protection Agency
                     Region 5, Library (PL-12J)
                     77 West Jackson Boulevar.d, 12th Floor
                     Chicago, IL  60604-3590

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      HUMAN HEALTH AND AQUATIC LIFE
     LITERATURE SEARCH AND DATA BASE
              EVALUATION FOR
            ENDOSULFAN SULFATE
   U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF WATER REGULATIONS AND STANDARDS
     CRITERIA AND STANDARDS DIVISION
             WASHINGTON, D.C.

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                          TABLE OF CONTENTS
INTRODUCTION 	     1
SCOPE OF SEARCH 	     2
SUMMARY OF FINDINGS 	     3
    Aquatic Toxicity 	     3
         Endosulfan 	     3
         Endosulfan Sulfate 	     3
    Health Effects 	     7
         Endosulfan 	     1
         Endosulfan Sulfate 	    11
CRITERIA EVALUATION AND RECOMMENDATIONS 	    12
    Aquatic Toxicity 	    12
    Human Health 	    12
REFERENCES 	    16
                            LIST OF TABLES


Table 1.  Summary of Aquatic Toxicity Literature
          Review of Endosulfan 	     4
Table 2.  Summary of Human Health Effects Literature
          Review of Endosulfan 	     8
Table 3.  Data Requirements for Calculation of Aquatic Life
          Interim Criteria—Endosulfan Sulfate 	    13
Table 4.  Data Requirements for Calculation of Human Health
          Interim Criteria—Endosulfan Sulfate 	 	    14

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                    HUMAN HEALTH AND AQUATIC LIFE
                   LITERATURE SEARCH AND DATA BASE
                            EVALUATION FOR
                          ENDOSULFAN SULFATE
                 U.S. ENVIRONMENTAL PROTECTION AGENCY
              OFFICE OF WATER REGULATIONS AND STANDARDS
                   CRITERIA AND STANDARDS DIVISION
                           WASHINGTON,  D.C.
                             INTRODUCTION


    Endosulfan is an organochlorine of the cyclodiene group with the
chemical name 6,7,8,9,10,10-hexachloro-l,5,5a,6,9,9a-hexahydro-6,9-
methano-2,4,3-benzo-dioxathiepin-3-oxide.  The  most  commonly used
trademark of endosulfan is Thiodan.  The principle producers of
endosulfan are Excel  Industries,  Ltd., India; FMC Corp., USA;
Hinduston Insecticides Ltd.,  India; Hoechst  AG,  West Germany; Hooker
Chemical and Plastics Corp., USA., I. Pi. Ci.   S. p. A., Italy.,
Maichteshim-Agan, Israel; and Velsicol  Chemical Corp., USA.
Endosulfan sulfate is a metabolite of both the A and B endosulfan
isomers of the parent compound endosulfan.   Endosulfan sulfate has
been found in tissues of both fish and rats as well as in soils where
it is reported to be more persistent than the parent compound (McEwen
and Stephenson,  1979).

    Production of endosulfan in the United States was 3 million pounds
in 1974  (U.S.  EPA,  1980).  -The pesticide  is  used in  agriculture for
control of a number of insect species and mites on deciduous, citrus
and fruit trees,  vegetables, forage crops, grains, tobacco, coffee,
tea,  and forest trees (McEwen and Stephenson, 1979).   Endosulfan is a
brown,  crystalline solid with a terpene-like odor and the following
physiochemical characteristics:


           Molecular weight         406.95
           Vapor pressure           9 x 10-3 mm Hg at 8C°C
           Solubility in water      60-150 ppm
           Melting point            70-100P°C.

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     Endosulfan has a low water solubility and is relatively short-
lived in water systems (McEwen and Stephenson,  1979).  Endosulfan
sulfate is an oxidation product of endosulfan with  the chemical name
6,7,8,9,10,10-hexachloro-l,5,5a,6,9,9a-hexahydro-6-9-methano-2,4,3-
benzodioxathiepin-3,3 dioxide.  Endosulfan  sulfate  reaches maximum
concentrations on plant surfaces and in soils 10 to 12 days after
application of the parent compound (Cassil and Drummond,  1965).
Fourteen days after application,  endosulfan sulfate comprised  about 50
percent of total endosulfan residues on leaves  of sugar beets  (Goebel
et al.,  1982).  Endosulfan sulfate levels in soil were 2 to 7 times
greater than the parent compound 2 to 15 months  after application of
0.5 kg  active ingredient  of endosulfan per hectare  to sugar beet
fields (Goebel et al.,  1982).  Additionally,  levels of the sulfate
metabolite in water were up to 3 times greater than  endosulfan shortly
after heavy application of parent compound to adjacent rice fields
(Goebel et al., 1982).

    Although certain soil bacteria metabolize endosulfan  to endosulfan
sulfate, fungi are the major microbial producers of the metabolite in
soils (Rup and Saxena, 1982).   Endosulfan sulfate forms in both the
presence and absence of ultraviolet radiation;  its production  is
positively correlated with  temperature  (Cassil and  Drummond,  1965.,
Goebel et al., 1982).  The metabolite has a molecular weight of 422.9,
a melting point of 181°C,  and less volatility than the parent  com-
pound,  resulting  in  greater persistence time (Goebel et  al.,  1982).

    Endosulfan sulfate is also a metabolic  byproduct  in animals
which is excreted  rapidly and is reportedly similar in toxicity to
the parent compound in rats (Cassil and Drummond,  1965; McEwen and
Stephenson,  1979., Das and Garg, 1981,  Matthiessen  et al.,  1982).

    The EPA published an Ambient Water Quality Criteria  Document for
endosulfan which set criterion levels for aquatic life  and human
health effects for endosulfan only  (EPA, 1980).  Endosulfan sulfate
was mentioned throughout the document but was not included  in  criteria
development.  The investigation presented here evaluates  data  compiled
subsequent to the development of the endosulfan  criteria  and evaluates
endosulfan sulfate data with respect to requirements for  criteria
development.


                           SCOPE OF SEARCH


    Sources were identified though a computerized literature search of
TOXLINE, TOXBACK,  NTIS and Toxicology Data Base  focusing  primarily on
dose-response studies published from 1965 to the present. Quality
assurance/quality control measures used during  the study  were eva-
luated for the use of positive and negative controls, replication, and
chemical analysis of  test concentrations.  Other information,  such as
bioaccumulation/bioconcentration, food chain, ecological, and health
effects data were obtained where available.

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    Studies were evaluated with respect to guidelines established by
the U.S.  EPA in "Guidelines  and Methodology Used in Preparation of
Health Effect Assessment Chapters of the Consent Decree Water Quality
Criteria Documents" (FR 45:79347,  November 28, 1980)  and the "Guide-
lines for Deriving Numerical National Water Quality Criteria for the
Protection of Aquatic Life  and Their Uses"  (Stephan et  al.,  1985).

    Data on the toxicity of endosulfan sulfate to aquatic organisms
and a review of human health effects are presented.  Interim criteria
are estimated based on the summarized data and recommendations are
made for additional studies.


                         SUMMARY OF FINDINGS

                           Aquatic Toxicity

Endosulfan

    Few studies on the aquatic toxicity of endosulfan have been
reported using species native  to the U.S.  since the publication of the
ambient water quality criteria for  endosulfan in 1980 (U.S. EPA,
1980).   Acute toxicity values reported since 1980 for invertebrates
ranged from  2.3 ppb for the stonefly Pteronarcys sp.  to 9500 ppb for
the fresh water fairy shrimp Artemia salina (Table 1). Acute values
for Daphnia magna and Daphnia p_u_lex ranged from  130 to  740 ppb, which
fall within the range of acute values  (62-740 ppb) for cladocera
reported in  the 1980 water  quality  criteria for endosulfan (U.S. EPA,
1980).   The mean value for acute toxicity for Daphnia magna was 435
ppb and the mean chronic value was  18 ppb.  Therefore, the acute-
chronic ratio was 21, which also  falls within those  ratios (4.9-38)
reported in the 1980 criteria document.   Acute values for inverte-
brates published since  1980  include 5.8 ppb for  the amphipod  (Gammarus
lacustris);  2.3 ppb for the stonefly  (Pteronarcys  sp.);  and 60-70 ppb
for the damsel fly  (Ischnura sp.).  Although these values are in close
agreement with acute values  reported in the 1980 criteria document,
the authors of these studies did not report quality assurance or
control procedures.  The range  of acute values  for the  remaining fresh
water invertebrate  species  was from 10 ppb  for  the snail  (Ancylus  sp.)
to 9500 ppb for the fairy shrimp (Artemia salina).  These values were
also reported without mention  of quality assurance methods.

    The acute values for fishes exposed to endosulfan ranged from  1.1
ppb for rainbow trout  (Sa_lmo gairdneri) to 11 ppb  for carp  (Cyprinus
carpio).   Although these values are in close agreement with acute
values  for  the same species  in the  1980 water quality criteria,
detailed quality control methods  were not  mentioned  in  these studies.

Endosulfan Sulfate

    No reports of acute endosulfan sulfate toxicity to aquatic
organisms were found.   One  study,  however,  reported exposing a green

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alga, Chlorella vulgaris,  and bluegreen alga, Phormidium sp.,  to
endosulfan sulfate for 120 hours and 14 days,  respectively (Goebel  et
al.,  1982).  Levels of endosulfan  sulfate  less than 10 ppm had no
effect on photosynthetic efficiency of Chlorella while levels  greater
than 2 ppm caused decreased cell division.   A 20 ppm endosulfan sul-
fate exposure produced a color change in Phormidium, while 1.25 ppm
had no effect.   It is uncertain  from this  report whether these algae
were exposed to the metabolite directly or indirectly as a result of
exposure to the parent compound.

    Endosulfan sulfate residues have been reported in fish tissues
that were exposed to endosulfan.  After 28 days of exposure to
endosulfan and significant bioconcentration was observed in the
striped mullet (Mu^gJ.1. cephalus);  endosulfan sulfate comprised nearly
all  of  the endosulfan residues  detected (Schimmel et  al.,  1977).
Similarly, endosulfan sulfate accounted for nearly all residues of
endosulfan in three species of marine fishes exposed to endosulfan  for
4 days  (Schimmel et al.,  1977).  In contrast, however, nearly  all of
the endosulfan residues detected in fathead minnows (Pimephales
promelas) were the A and B isomers,  indicating an  inability by this
species to completely metabolize  endosulfan (U.S.  EPA, 1980).   The
excretion of endosulfan sulfate and endosulfan by fishes is rapid,  and
is complete 2-14 days after dosing (Gorbach, 1972; Schimmel et al.,
1977) .

    Endosulfan sulfate has been detected in waters and sediments
contaminated with the parent compound.  Endosulfan sulfate  levels in
water were 0.06 to 0.19  ppb,  while endosulfan levels  were  0.1 to 0.13
ppb after application of parent compound to nearby rice fields in Java
(Gorbach et al.,  1971).   Following a fish  kill in Sincoe,  Ontario,
bottom sediments of the  affected pond had endosulfan sulfate levels of
1.1 to 1.2  ppb  and endosulfan levels of 0.9 to 1.0 ppb while neither
compound was detected in the water (Frank,  1972).   After application
of endosulfan  (6 times in 3 months)  to  nearby vegetation at the rate
of 58.5  g/hectare  in  Botswana, the ratio of  endosulfan sulfate to
endosulfan in  fish tissues increased with time from about 1 to over 6
in waters with levels of 0.2 to 4.2  ppb  endosulfan (Matthiessen et
al., 1982).

                            Health Effects

Endosulfan

    Acute toxicity (LD50) values for endosulfan to rats ranged from 8
mg/kg by intraperitoneal injection to 781 mg/kg for dermal exposure
(Table 2).  After  a single oral  dose of  40 ppm and repeated oral doses
of 20 ppm,  increases  in  blood glucose were reported  at both levels
with a decrease in plasma calcium reported at the higher dosage (Garg
and Kunwar, 1980).  LD50 values for mice  ranged from  6.9 to 13.5 mg/kg
by intraperitoneal injection and 147 to 359 mg/kg for rabbits  by
dermal  and percutaneous  exposure.   An LC50 for guinea pigs was 1,000
mg/kg from dermal exposure and 30 mg/kg for dogs  from oral exposure.

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Chronic effects for rats included a reduction in weight gain from oral
exposure to 0.5 ppm for 9 weeks (Das and Garg,  1981)  and increased
female mortality and decreased male testicular weight at 5 ppm for 2
years of oral  exposure  (Gupta and Gupta, 1979).   Two years of dietary
exposure for dogs at levels of 3 ppm resulted in no observed toxic
effects (Goebel et al., 1982).   OPP has judged the NOEL for dogs to be
30ppm,  based on two long  term  (1 and 2  years) studies.

    Teratogenic effects were observed at levels of 5 and 10 mg/kg
endosulfan after intraperitoneal injection to pregnant rats during
embryogenesis  (Gupta and Gupta,  1979).   On the other hand,  no effects
on female rats or offspring were observed at dietary levels of 1.5 ppm
during the 15th-16th day of pregnancy or at 50 ppm in a three genera-
tion study  (Goebel et  al.,  1982).

    Effects of endosulfan on mutagenicity were contradictory.
Although mortality occurred at 22-55 ppm after 5 days of exposure by
intubation in rats,  no inhibition  of mitosis or chromosome damage was
evident in cells of bone marrow and seminiferous tubules (Dikshith and
Datta,  1978).   Additionally, 48 hours of oral exposure to rats at 43.3
ppm caused no increase in clastogenesis (chromosonal breakage)  in bone
marrow cells (Usha Rani et al.,  1980).   No evidence of  mutagenicity
was found in Salmonella sp. by microsomal assays  (Quinto et al.,  1981)
However, a significant increase in mutation,  gene conversion,  and
chromosonal breakage occurred at 1 percent endosulfan (weight/volume)
in solution for the fungus Sacchavomyces cerevasia (Yadav et al.,
1982).   Furthermore,  after 24 hours exposure of 100 and 200 ppm in the
diet of the fruit fly Drosophila melanogaster, an increase was found
in the percent of sex-linked recessive lethal genes in first instar
larvae and 2-day old adults (Velazquez et al., 1984).

    Exposure to endosulfan  in the diet  of rats (223 and 952 ppm)  and
mice (2 and 3.9 ppm)  for up  to  106  weeks resulted in  high mortality of
male rats while no carcinogenicity was evidenced in female rats and
mice (NCI,  1978).  However,  subsequent  histopathological examinations
indicated significant increases in sarcomas and carcinomas (primarily
in endocrine organs) of female rats at both low and high doses
(Reuber,  1981).  Although no significant increase in carcinomas
occurred in male rats, a high incidence of sarcomas was found,  but was
not significantly greater than controls  (Reuber,  1981).   Because of
extremely high and variable doses of endosulfan and high incidences of
neoplasms in control rats,  the carcinogenicity of endosulfan to rats
is uncertain from this  study  (Reuber,  1981).


Endosulfan Sulfate

    Although the toxicity of endosulfan sulfate to mammals has been
reported to be similar to the parent compound, B endosulfan and endo-
sulfan sulfate had LD50 values of 76 mg/kg while B endosulfan exhi-
bited an LD50 of 240 mg/kg  (Goebel et al.,  1982).   Endosulfan sulfate
was less effective than the parent compound in altering mitochondrial


                                  11

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enzymes in rat liver homogenates (Dubey et al.,  1984).   Additionally,
endosulfan sulfate showed negative results for mutagenicity in Ames
tests (Quinto et al., 1981).

    The majority of data from the literature with respect to endosul-
fan sulfate and mammals deals with tissue levels of the metabolite
after oral exposure to endosulfan.   Endosulfan sulfate was the most
common metabolite in the organs, tissues, and feces of rats  (Whitacre,
1970)  and accounted for 15-80 percent of total endosulfan residues in
adipose tissues of rats fed  0.5 and 100 ppm of parent compound for 9
to 18 weeks (Das and Garg,  1981).   Endosulfan sulfate was the major
form of endosulfan in liver, small intestine, visceral fat, and feces
of mice fed endosulfan  at  10 ppm for 28 days (Deema et  al.,  1966).

              CRITERIA  EVALUATION AND RECOMMENDATIONS

                           Aquatic Toxicity

    Until required studies are conducted, a AWQ criterion for
endosulfan sulfate cannot be calculated.  The current freshwater and
salt water aquatic life criteria (24-hour average) for endosulfan are
0.056  ppb and .0087  respectively (U.S.  EPA,  1980).  Only two studies
were found since the publication of the criterion which provide
additional data appropriate  for criteria calculations.  The mean acute
values for Daphnia magna and Crangona septemspinosa fall within the
ranges reported for these and similar species in the 1980 criteria.
It is unlikely that the incorporation of these acute values would
alter the current criteria.

    Endosulfan sulfate has been detected at significant levels in
tissues of fishes and in the waters and sediments adjacent to areas of
endosulfan application.  No data on the acute or chronic toxicity of
endosulfan sulfate to aquatic organisms were found in this investiga-
tion.   Because of the lack of these data, neither recommendation for
an interim criterion nor comparison with the existing endosulfan
criterion can be made.   Data elements required for criteria develop-
ment formulae as defined by  EPA  (Stephan et al.,  1985)  are listed in
Table 3.   This advisory recommends the use of endosulfan criteria
values in the absence of other data.

                             Human Health


    The current criterion level for endosulfan is 74 ug/L for
ingestion water  (U.S.   EPA,  1980).  This criterion was based upon a
no-observed-effect level  (NOEL)  of 0.4 ppm for mice fed endosulfan for
78 weeks (U.S.  EPA,  1980).   Because no  acceptable data were found
(Table 4) reporting a NOEL less than 0.4 ppm for  mammals,  no revision
of the 1980 criterion for endosulfan is warranted.  Although acute
toxicity values for endosulfan sulfate  are similar to endosulfan for
rats,  no long-term studies of toxicity for endosulfan sulfate have
been published.  Because studies required by EPA (FR 45:79347) for


                                  12

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      TABLE 3.  DATA REQUIREMENTS FOR CALCULATION OF AQUATIC LIFE
                INTERIM CRITERIA—ENDOSULFAN SULFATE
  Criterion Requirements
     Aquatic Toxicity
Available Data
  Acceptability
of Available Data
Acute Test Results from tests on:

  A salmonid (class Osteichthyes)         NO

  A warm water species                    NO
  commercially or recreationally
  important (class Osteichthyes)

  Another family in the phylum            NO
  Chordata (fish, amphibian, etc.)

  A planktonic crustacean                 NO
  (cladoceran, copepod, etc.)

  Benthic crustacean  (ostracod,           NO
  isopod, scud, crayfish, etc.)

  Insect  (mayfly, dragonfly,              NO
  damselfly, stonefly, mosquito, etc.)

  Phylum  other than Arthropoda/           NO
  Chordata (Rotifera, Annelida,
  Mollusca)

  Another family of insect                NO

Acute-chronic ratios with species from
three different families:

  One fish                                NO

  One invertebrate                        NO

  Acutely sensitive freshwater            NO
  animal  species

Acceptable test results from a test with:

  Freshwater algae                        NO

  A vascular plant                        NO

Bioaccumulation factor with a fresh-      NO
water species (if a maximum permissible
tissue concentration is available)
                                  13

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         TABLE 4.  DATA REQUIREMENTS FOR CALCULATION OF HUMAN
                   HEALTH INTERIM CRITERIA--ENDOSULFAN SULFATE

 Criterion Requirements                                 Acceptability
  Human Health Effects             Available Data     of Available Data

Non-Threshold:
  Carcinogen                             NO
  Tumor incidence tests (Incidence of    NO
    tumor formation significantly more
    than the control for at least one
    dose level), or
  Data set which give the highest        NO
    estimate of carcinogenetic risk, or
  Lifetime average exposure tests, or    NO
  Human epidemiology studies             NO
    (if available, not required)

Threshold:
  Non-carcinogens
  No observed adverse effect level       NO
    (at least 90-day), or
  Lowest observed effect level           NO
    Lowest observed adverse effect       NO
    level

Acceptable Daily Intake:
  Daily water consumption                YES                YES
                                                     (EPA assumption)
  Daily fish consumption                 YES                YES
                                                     (EPA assumption)
  Bioconcentration factor                NO
  Non-fish dietary intake                YES                YES
                                                     (EPA assumption)
  Daily intake by inhalation             NO

Threshold Limit Value:
  (Based on 8-hour time-weighted         NO
    average concentrations in air)

Inhalation Studies:
  Available pharmacokinetic data         NO
  Measurements of absorption efficiency  NO
  Comparative excretion data             NO
                                  14

-------
calculation of a water quality criterion for endosulfan sulfate are
currently lacking (Table 4),  no recommendation of an interim criterion
nor comparison with the existing criterion for endosulfan can be made.
This advisory is recommending that concentrations of endosulfan sul-
fate not exceed the criterion for endosulfan, 74 ug/L,  in the absence
of other data.
                                  15

-------
                              REFERENCES

Cassil, C. C., and P. E.  Drummond.   1965.  A plant surface oxidation
product of endosulfan.  J. Econ.  Entomol. 58:356.

Das,  N., and  A. Garg.  1981.  Effect of endosulfan in female  rats
growing on low and high protein cereal diet.   Pestic.  Biochem.
Physiol.    15:90-98.

Deema, 0.,  E. Thompson,  and G. W. Ware.  1966.  Metabolism, storage
and excretion of 14C endosulfan in the mouse.   J. Econ.  Entomol.
59:546.

Dikshith,  T.S.S., and K. K. Datta.   1978.   Endosulfan:   Lack  of
cytogenetic effects in male rats.   Bull.  Environ. Contam.  Toxicol.
20:826.

Borough, H. W.,  I. Huhtanen,  T. C. Marshall, and H.  E. Bryant.   1978.
Fate of endosulfan in rats and toxicological  considerations of apolar
metabolites.   Pesticide Biochemistry and Physiology.  8:241-252.

Dubey, R.  K., V. Beg Mirza, and J.  Singh.   1984.   Effects of endosul-
fan and its metabolites on rat liver mitochondrial respiration and
enzyme activities in  vitro.   Biochem. Pharmacology.   33:3405-3410.

Federal Register.   1980.   Guidelines and  methodology used  in  prepara-
tion of health effect assessment chapters of the consent decree  water
quality criteria documents.  November 28, 1980.   45:79347-79356.

Frank, R.   1972.  A  fish kill near Simcoe,  Ontario.  Unpublished
report.  Ontario Ministry of Agriculture  and Food, Guelph, Ontario.
In:  National Research  Council of  Canada, 1975.   (As cited in U.S.
EPA,  1980)

Garg, A.  and K.  Kunwar.   1980.  Endosulfan intoxication-blood glucose,
plasma electrolytes,  Ca  levels and hexokinase in rats.   Indian J.
Biochem.  Biophys.  17:113.

Goebel, H., S.  Gorbach, W. Knauf,  R. Rimpau, H. Huttenbach.   1982.
Properties, effects,  residues, and  analytics  of  the  insecticide
endosulfan.  Vol.  28.  In:  Residue reviews,  residues of pesticides
and other  contaminants in the  total  environment.  Springer-Verlag, New
York, NY.

Gorbach,  S. G.   1972.   Terminal  residues  of  endosulfan.   Proc. 2nd
Int.  Congr.  Pestic. Chem.  6:283.  (As cited in U.S. EPA, 1980)

Gorbach, S.,  R. Haarting, W. Knauf,  and H. Werner.   1971.  Residue
analyses in the water system if East Java (River Brantas,  ponds,
seawater)  after continued large-scale application of Thiodan in  rice.
Bull. Environ.  Contam. Toxicol.   6:40.
                                  16

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U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard. 12th Floor
Chicago, IL  60504-3590

-------
Gupta, P. K. and R. C. Gupta.  1979.  Pharmacology, toxicology, and
degradation of endosulfan.  A review.  Toxicology.  13:115-130.

Johnson, W. W., and A. T.  Finley.  1980.   Handbook of acute toxicity
of chemicals to fish and  aquatic  invertebrates.  Res. Bull. 137,  U.S.
Dept. Int. Fish. Wildl. Serv., Washington, DC.

Matthiessen,  P.,  P. J.  Fox, R. J.  Douthwaite, and A. B. Wood.   1982.
Accumulation of endosulfan residues in fish and their predators after
aerial spraying for the tsetse fly in Botswana.  Pestic.  Sci.   13:39-
48.

McEwen,  F. L.,  and G. R. Stephenson.   1979.   pp. 177-179.   In:  The
use and significance of pesticides in the environment.  John Wiley and
Sons, Inc., New York.

National Cancer Institute  (NCI).   1978.   Bioassay  of endosulfan for
possible carcinogenicity.  Natl. Cancer Inst. Div.  Cancer Cause and
Prevention.  Bethesda,  Maryland.  DHEW Pub.  No. (NIH) 78-1312.   (As
cited in U.S.  EPA, 1980)

Nebeker,  A. V.  1982.   Evaluation  of  a Daphnia  magna renewal life-
cycle test method with silver and endosulfan.  Water Res.  16:739-744.

Quinto,  I., G.  Martire, G. Vricella,  F. Riccardi, A. Perfumo,  R.
Giulivo,  and F. DeLorenzo.  1981.   Screening of 24 pesticides  by
Salmonella/microsone assay:  Mutagenicity of benazolin,  metoxuron and
paraoxon.  Mutat.  Res. 85:265.

Reuber,   M. D.   1981.   The role of toxicity in the  carcinogenicity of
endosulfan.  Sci. Total  Environ.  20:23-47.

Rup, L.  and D.  M.  Saxena.   1982.   Accumulation, metabolism and effects
of organochlorine insecticides on microorganisms.  Microbiological
Reviews.   46:95-127.

Schimmel, S. C.,  J. M.  Patrick,  and A. J. Wilson.  1977.  Acute toxi-
city and bioconcentration of endosulfan by estuarine anhnals.   ASTM
Spec. Tech. Publ.  634:241-252.

Stephan, C. E., 0. I.  Mount, D.  J. Hansen, J. H. Gentile, G. A.
Chapman,  and W. A. Brungs.   1985.  Guidelines for  deriving numerical
national water quality criteria for the protection of aquatic
organisms  and their uses.  U.S.  Environmental Protection Agency,
Office of Research and  Development, Environmental  Research
Laboratories,  Duluth,  MN.

United States Environmental  Protection  Agency  (U.S. EPA).  1980.
Ambient water quality  criteria for endosulfan.   EPA-440/5-80-046.
U.S.  EPA,  Washington, DC.   National Technical Information Service
PB81-117574.
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