United States
Environmental Protection
Agency
Office of Pesticides Prograrrs
Washington, DC
EPA £40/9-86-133
July 198S
Hazard Evaluation Division
Standard Evaluation Procedure
Fish Early Life-Stage    Support Document 5o

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          HA2AR0 EVALUATION DIVISION

        STANDARD EVALUATION PROCEDURE

          FISH EARLY LIFE-STAGE TEST
                 Prepared by


            Miachel Rexrode, M.S.

                     and

          Thomas M. Armitage, Ph.D.
Standard Evaluation Procedures Project Manager
              Stephen L. Johnson
          Hazard Evaluation Division
         Office of Pesticide Programs
 United States Environmental protection Agency
          Office of Pesticide Programs
            Washington, B.C.  20460

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                  STANDARD EVALUATION PROCEDURE

                             PREAMBLE


     This Standard Evaluation Procedure (SEP) is one of a set of

guidance documents which explain the procedures used to evaluate

environmental and human health effects data submitted to the

Office of Pesticide Programs.  The SEPs' are designed to ensure

comprehensive and consistent treatment of major scientific topics

in these reviews and to provide interpretive policy guidance

where appropriate.  The Standard Evaluation Procedures will be

used in conjunction with the appropriate Pesticide Assessment

Guidelines and other Agency Guidelines,  While the documents were

developed to explain specifically the principles of scientific

evaluation within the Office of Pesticide Programs, they may also

be used by other offices in the Agency in the evaluation of

studies and scientific data.  The Standard Evaluation Procedures

will also serve as valuable internal reference documents and will

inform the public and regulated community'of important consider-

ations in the evaluation of test data for determining chemical

hazards.  I believe the SEPs will improve both the quality of

science within EPA and, in conjunction with the Pesticide Assess-

ment Guidelines, will lead to more effective use of both public

and private resources..
                                    W. Melonef Director
                               Hazard Evaluation Division

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                          TABLE OF CONTENTS
  I. INTRODUCTION

       A, When Required	   I
       B. Purpose	.	   1
       C. Test Material	. ...	   2
       D. Acceptable Protocols  ..........P....,,.....,. •  2
 II.  MATERIALS, METHODS, AND REPORTING REQUIREMENTS

       A. Biological System	  2
            1. Acceptable Species	  2
            2 . Source	 *  2
            3. Eggs from Adult Fish	  3
            4. Embryo Exposure (Test Begins)	»  3
            5. Post Hatch, Larval Fish	  4
            6. Controls	  5
            7. Data Endpoints ...........................  5
       B. Physical System	  5
            1. Test Water .. . .'	  5
                 a. Saltwater Pish	  5
                 b. Freshwater Fish	  6
            2. Temperature	  6
            3, Photo period	  6
            4 . Dosing Apparatus	  6
            .5. Toxicant Mixing	  6
            6. Test Vessels  .....,,.»	  6
            7 . Embryo Cups 	,.,«...	  6
            8. Flow Rate	  7
            i . Aeration	  7
       C. Chemical System	..»..»....,....  7
            1. Concentrations	  7
            2. Measurement of Other Variables ..........  7
            3. Solvents	  7
       D. Calculations	 *  8
III.  REVIEWER'S EVALUATION

       A. Verification of Statistical Analysis .........  8
       B. Conclusions ..................................  8
            1. Categorization of Results	  8
            2 . Rationale	.'......  9
            3. Reparability	  9
            4. Descriptive Conclusions .................  9
  REFERENCES .	  10

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                     llJ[§H_gARLY LIFE-STAGE


I.  INTRODUCTION

     A.  When Required

     The fish early life-stage test1/ is required to support an
end-use product is intended to be applied directly to water or
is expected to transport to water from the intended use site,
and when any one of the following conditions apply:

     0  If the pesticide is. intended for use such that its
        presence in water is  likely to be continuous or recurrent
        regardless of toxieity, as revealed by studies required
        by 40 CFR §158.130 "'~ ~

     0  If any LC^Q or £€50 value determined in the testing
        required by 40 CFR §158.145 [§§ 72-1, -2, or ~3J is
        less than 1 mg/1;

     '°  If the estimated environmental concentration in water
        is equal to or greater than 0.01 of any £€59 or *LC$Q
        determined in acute testing required by 40 CFR §158.145;
        or

     0  If the actual or estimated environmental concentration
        in water resulting from use is less than 0.01 of any
        EC50 or L^5Q determined in testing required by 40 CFS
        §158.145 and any of the following conditions exists:

             Studies of other organisms indicate the repro-
             ductive physiology of fish and/or invertebrates
             may be affected;

             Physicochenucal  properties indicate cumulative
             effects? or

             The pesticide is persistent in water (e.g., half-
             life in water greater than four days),

     B.  Purpose

     0  To establish chronic  toxieity levels of the active
        ingredient to fish;
    In cases where risk criteria for both fish and invertebrates
    are exceeded, the more sensitive organism must be tested in
    a fish early life-stage or invertebrate life cycle study.
    Both studies may,, however, may be required to complete a
    risk assessment.

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                              -2-
     0  To compare toxicity  information with measured or
        estimated pesticide  residues in art aquatic environment
        in order to assess potential impact to fish;

     8  To provide support for precautionary label statements;
        and

     0  To indicate the need for further laboratory testing or
        field testing.

     C.  Test Material

     Testing must be conducted with the technical grade of the
active ingredient (a,i.)«  If more than one active ingredient
constitutes a technical product, the technical grade of each
active ingredient must be tested separately.

     D,  acceptable Prg_tgcols

     The Ecological Effects Branch (EEB) does not endorse any
one protocol.  It is sometimes necessary and desirable to alter
the -procedures presented in published protocols to meet the
needs of the chemical or test organisms used.  However, EEB
does recommend some protocols as guidance for performing a fish
early life-stage toxicity test.  These protocols include;

     American Public Health Association, American Water Works
     Association and Water Pollution Control Federation  (1985)
     Standard Methods for the Examination of Water and Wa&tewater
     Sixteenth Edition.  Publication Office:  American Public
     Health Association, -1015 18th Street NW, Washington,
     DC 20036.  854 pp.

     Goodman, L.R.   '(1985}  Comparative Toxicological
     Relationship Demonstrated in Early Life.  Stage Tests with
     Marine Fish,  Environ. Res. Lab., Gulf Breeze, PL.
     EPA/60Q/*85/135,

     Middaugh, D.P., M.J. Hemmer, and L.R. Goodman,  1987,
     Methods for Spawning, Culturing and Conducting Toxicity
     Tests with Early Life Stages of Four Atherinid Fishes: The
     inland silverslde, Menj.dj_a beryllina, Atlantic sllverstde,
     M. menidia, tidewater silverside, M. peninsulas, and
     California" grunion, Leuresthes tenuis.  Office of Research
     and Development, U.S. Environmental Protection Agency,
     Environmental  Research Laboratory at Gulf Breeze Florida,
     EPA/600/8-87/D04 (Januraryp'1987) » 56 pp.

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                               -3-


II.   MATERIALS, METHODS, AND REPORTING REQUIREMENTS

      A.  Biologic aJLjS y s t e m

           I.   AcceptableSpecies

      The selected species should have a demonstrated sensitivity
 to  known toxicants.  If possible, they should be species that
 occur in the  area of exposure or be related to exposed species.

      The acceptable freshwater species,(1, 2) are rainbow trout
 (Saj.mg g_a_irdrier i) ,  brook trout [Salve jLinus fontinalis) , coho
 salmon (Onco_rKyiichus kisutch) , Chinook (O. tshawytscha) , bluegill
 (Lepomis macrochirus) , brown trout (S. ;t£u_tta) , lake trout  (S_.
 namaycush) /northern pike (Esox lucius), fatKead minnow
 {Pimephaj-es pj^melas) , white sucker ("Catostomus commersuni) ,
 and channel catfish (Ictalurus punctatus).  The silverside
 species (Menidia roenidia , menldjji bejcyll_i_na, and Mg£ULd_i_a
 peninsulas)  and the sheepshead minnow  (Cyprinodon variegatus)
 are acceptable estuarine species.{1, 2)

           2.   Source

      Gametes  used for conducting a fish early life-stage test
 roay be obtained:  1)  directly from hatcheries or commercial
 sources; 2)  from wild populations of adult fish collected in
 the field;  oc 3) from brood fish cultured in the laboratory*
 Whenever salmon or trout are used, they should be obtained  from
 a hatchery  that has been certified disease-free.

           3.   Eggs from Adult Fish

      Eggs can be obtained either by stripping ripe females or
 by  collecting eggs deposited directly on substrata.  Manual
 removal is  usually conducted on salmon, pike, trout, bluegill,
 and silversides.  This procedure is usually preceded by killing
 or  by anesthetizing ripe females in MS-222 ( » iQO-ppm) or
 quinaldine  {  « 10 ppm).  Eggs are forced from the vent by
 manual or air pressure techniques.  If fish are sacrificed, an
 incision is made along the median ventral line from the vent to
 the pectoral  fins of ripe females.  Care should be taken to
 keep eggs free from mucous and blood.  Eggs still adhering  to
 the ovaries ace not taken,  Eggs from at least three females
 should be fertilized with sperm from at least three males.
 Male specimens (e.g., salmon, trout)  anesthesized with • 100
 ppm of MS-222 can be collected by gently pressing the sides of
 'the abdomen.(1)  Sperra collection from pike is best accomplished
 by  sacrificing the  fish.(l)  The fish are killed and the testes
 removed through an incision in the abdomen.  Testes are placed
 in  clean cheesecloth and squeezed to extrude milt.(l)

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                                -4-
       Fertilized eggs may be shipped but can be damaged by  rough
  handling.   Eggs should be water hardened .for one-hour prior  to
  shipping and kept cool (< 10 °C) . (1)  Preferably eggs and sperm
  should  be  shipped separately with plenty of ice and a blanket
  of  pure oxygen on the sperm.  Unfertilized eggs and semen  can
  be  transported for a period of 24 hours after stripping if they
  are kept in an air-tight container . (1) Using a 0.75 percent
  saline  solution when mixing eggs and semen may facilitate
  fertilization,

       Eggs  can 'be obtained from channel catfish, fathead minnow,
  sheepshead minnow, and bj.uegi.ll by facilitating natural spawning
  either  in  the laboratory or a brood pond.(lf 3, 4, 5, 6}

            4 .   Embryo Exposure (Test B_eg_i_ns_)_
               can  be  either fertilized prior to toxicant exposure
 or  fertilized in  the test solution.  Verification of the precise
 embryonic  stage at the  beginning of the exposure should be
 attempted  if  possible.
                 to/initiate Jrfie study shouldx&e at the &ysd st^ge,
 and E&ficted  from  a  group^of which 70% ate fertilizer;

      A minimum  of  20 embryos are randomly selected per replicate
 cup with  four replicates  per concentration (80 embryos total) . (1)
 Cups containing  embryos  are placed into the exposure chambers,
 Water may  flow  directly  over the embryos in the cup or the cups
 may be oscillated  in the  test solution by means of rocker arm
 apparatus  driven by  a low speed electric motor,

      Embryos  should  be 2  to 24 hours old at the beginning of
 tfce_te.|5t:;L>  Twenty-four hours alter being placed in the incuba-
/tTon c~ups  they  should be  counted and examined for dead or
j heavily fungused individuals, which should be discarded without
 disturbing  the  viable embryos . ( 2}   This counting and examination
 is repeated on  a daily basis.  The range of time-to-hatch in
 each .cup .  is .species  specific as noted in table 1.
             Cu-e_. pLF           ^  -y-    xjn  U.^  44, a.
HAS,  old,  Sc^orvic)   eVu-yCxS j^ay   JJKL,

                        '^   ^   JD  daa
                                                   h,
          -  -W,- -te ••

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                              	c	
Table 1.  Average Time-to-Hatch for Several Species of Fish,
          Relative to Temperature(1)
       Species

Rainbow trout (Salmo gairdneri)
Brook trout (Salvelinus fontinalis)
Coho salmon (Oncorhynchus k_isutch)
Brown trout (Salvelinus trutta)
Lake trout (Salvelinus namaycush)
Chinook (Oncorhynchus tshawytscha)
Northern pike (Esox lucius)
Bluegill (Lepomis macrochirus)
Fathead minnow (Pimephales promelas)
Channel catfish (Ictaluras punctatus)
Sheepshead (Cyprinodon variegatus)

Silverside (Menidia menidia)
                                     Temperature  Days-to-Hatch
                                         10 °C
                                         10 °C
                                         10 °C
                                         10 °C
                                          7 °C
                                         10 °C
                                         15 °C
                                         28 °C
                                         25 °C
                                         26 °C
                                         30 °C
                                         25 °C
                                         25 °C
                                       31
                                       44
                                       55
                                       41
                                       72
                                       56
                                        6
                                        6
                                        5
                                       6-7
                                        4
                                        7
                                        8
          5.,  Post Hatch, Larval Fish

     When hatching is about 90 percent completed or 48 hours
after first hatch, live young fish should be counted.(1)  All
of the normal and abnormal live fish should be released into
the test chambers.(1) Fish numbers can be thinned to at least
30 per treatment.(1)   A test should be terminated if the average
percent of embryos (based on the number of embryos after
thinning) that produce live fry for release into the test
chambers in any control treatment is less than 50 percent or if
the percent hatch in any control embryo cup is more than 1.6
times that in another control embryo cup.(l, 3}

     Test fish over two days old (post hatch swim-ups) must be
fed live newly hatched brine shrimp.
     Fish should
feedings will be
                 be fed at least
      ------        j
meaningful endpoint.
                twice daily.  Time between
species specific, and must be based on a
                    Control and treatment
               of food if growth
teedings will be species specitic,
reliable hatchery feeding schedule.
fish must receive equal amrmni-c- r\f
«.*
amounts
                                                  is to be a
     Dead fish should be removed and recorded when/observed.
At a" minimum, the live fish should be counted (including those
which are lethargic or grossly abnormal in either swimming
behavior or physical appearance) 11, 18, 25, and 32 days after
hatching.(1)

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                               -6-
     Fisb should not be  fed  for  at  least  24 hours  prior  to
termination on day 32.   At termination, all live fish  should  be
weighed  (wet, blotted dry).

          6.  Controls

     A test is not acceptable  if  the average survival  of  the
controls at the end of the test  is  less than 80 percent  or  if
survival in any control  chamber  is  less than 70 percent.fi)
The relative standard deviation -(RSD = 100 x standard  deviation
divided by mean) of. weights  of the  fish that were  alive  at  the
end of the test in any control test chamber must not be  greater
than 40 percent. (1)              ,  _

     A negative control  (no  toxicant or carrier) and a carrier.
control  (when applicable) are  required,   Regardless of the
carrier used, the carrier concentration should be  equal  in  each
exposure concentration and carrier  control.  If they are  not,
the carrier concentration in the  control  (carrier) must  be  at
least as high as that in any toxicant test chamber.

          7,  Data Endpojnts

     A record of the results of an  acceptable test must  include
the number of erobryos hatched, -tine to hatch, mortality of
embryos, larvae, and juveniles,  time to swim-up, measurement of
growth, incidence of pathological "or histological  effects,  and
observations of other effects or  clinical signs in each  treat-
ment,  Endpoints defined in  terms of statistically significant
differences and biologically significant  differences are  based
on contingency table, or other hypothesis testing procedures
and regression analysis, concentration-effect curve analysis,
and other estimation procedures. (1}  Tests for chamber to chamber
heterogeneity within treatments are generally based on analysis
of variance or contingency table  procedures , (1)

     B .  Ph y s i c a 1 S y sj: en?

          1 .  Te s t_ Wa t e r_

              . a .   Saltvater
     1) "*est water may be natural  (sterilized ancl filtered to
remove particles 15 mierons and- larger) or a commercial mixture
(provided that there are no adverse affects to test organisms
or alterations in test material toxicity) ; 2} Natural seawater
is considered to be of constant quality if the weekly range of
salinity is .less than six percent, and if monthly pH range. is
less than 0.8 of a pH unit; 3)* Salinity should -be >_ 15 parts
per thousand; 4) Water must be free of pollutants. (7} Use of
ultraviolet light irradiation is recommended to sterilize the
test water.

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                              -7-
               b.  Freshwater Fish .

     1) Test water can be supplied from a well or-spring provided
that the source  is not polluted; 2) Water should be sterilized
with ultraviolet irridiation and tested for pesticides, heavy
metals, and other possible contaminants; 3) Hardness of 40 to
4-8 mg/L as CaCO3 and pH of 7.2 -to 7.6 is recommended;
4) Reconstituted water can be used.  Detailed descriptions of
acceptable procedures for preparing diluent are found in the
protocols by the American Society of Testing Materials  (1980).(2)

          2.  Temperature  .                                    . .
                         x. ~-—~~
     Test temperature depends upon the test species and should
not deviate by more than 2°C from the appropriate temperature
(refer to section A, 4).

          3-.  Photoperiod               '

     A photoperiod of 16L/8D can be used with a light intensity
of 400 to 800 Lux at the surface 'of the test'solution.  However,
in -general salmonid eggs should be incubated under dim  lighting
(< 20 ft-candles) or total darkness. (1)

          4 .  Dosing Apparatus. -

     Intermittent-flow proportional diluters as described by
Mount and Brungs (8) or continuous-flow serial diluters, as
described by Carton (7) should be employed.  A minimum  of five
toxicant concentrations with a dilution factor not greater than
0.50 and controls should be used.

          5.  Toxicant Mixing      -

     A mixing chamber is recommended to assure adequate mixing
of test material.  Aeration should not be used for mixing.
Separate flow splitter delivery tubes should run -from this
container to each replicate larval tank.(3)  Depending  upon the
apparatus used, a mixing chamber may not be required/ but it
must be demonstrated that the -test solution is completely mixed
before introduction into the test system.  Flow splitting
accuracy must be within 10 percent and should be checked
periodically for accurate distribution of test water to each
tank.(1)

          6. -  Test' Vessels-        -               *

     All test tanks should be of either all glass' or glass with
a stainless steel frame.  Exposure vessels will vary in size
according to the species under test.  Generally, it is  desirable
to have a depth of water of at least 15 to 30 cm.(1)

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                               -8-
           7.   Embryo Cups

      Embryo incubation cups should be made from 120 mL glass
 jars with the bottoms replaced with 40 mesh stainless steel or
 nylon screen.  Cups can be oscillated vertically (2.5 to 4.0
 cm)  in the test water (rocker arm apparatus,  2 rpro motor)  or
 placed in separate chambers with self-starting siphons.   Both
 methods should insure adequate exchange of water and test
 material.

           8.   Flow Rate

      Plow rates to larval cups should provide 90 percent
"replacement in 8 to 12 hours, (3)  Flow rate must be capable of
 maintaining dissolved oxygen at above /5 percent of saturation
 and  maintain  the toxicant level (concentration cannot drop
 below 20 percent with fish in the tank).

           9,   Aeration

      Dilution water should be aerated vigorously insuring  that
 dissolved oxygen concentration will be at or  near 90 to  100
 percent saturation.  Test tanks and embryo cups should not be
 aerated.

           C.   Chemical System

           1.   Concentrations

      A minimum of five concentrations of toxicant and a
 control,  (all replicated)  are used in this chronic  test.   A
 solvent control is added if a solvent is utilized.   At a
 minimum,  the  concentration of toxicant must be measured  in
 one  tank  at each toxicant level every week.  Water  samples
 should be taken about midway between top and  bottom and -the
 sides of  the  tank.  One concentration selected must adversely
 affect a  life-stage and  one concentration must not  affect  any
 life-stage.

           2.   Measurement of Other variables

      Dissolved oxygen must be measured at each'concentration
 at least  once a week.   Freshwater  parameters  in a control  and
 one  concentration must be analyzed once  a week.  These
 parameters  should include  pH, alkalinity, hardness,  and
 conductance.   Natural seawater  must maintain  a constant
 salinity  and  not fluctuate more than six percent weekly or a
 monthly pH  range of less than 0.8  of a pH unit.

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                                — Q —
            3.   Solvents

       If solvents other than water are necessary, they should be
  used sparingly and not to exceed 0.1 mL/L in a flow-through
  system.  The  following solvents are acceptable:(2)

                        dime thy Iforntamide
                        triethylene glycol
                        methanol
                        acetone
                        ethanol

       The development of chemical saturators for use with hydro-
  phobic chemicals may be used with most test chemicals.(6, 9)

       D.'.  Calculations                   •         •

       Data from these toxicity studies are of two types,
  continuous (i.e., length, weight) and discrete  (i.e., number of
  fish hatching or surviving).  In general, continuous data
  should be analyzed with the appropriate analysis of variance
  (ANOVA) technique followed by an appropriate multiple comparison
  test.  Dichotomous data should be analyzed using some form of a
  2x2 contingency table.

       As a part of the ANOVA, it is desirable to plot the
  residuals versus concentration and determine whether there have
  been any obvious violations of homoscedasticity on  the  assumption
  of normality.  All test results must be accompanied by  copies
  of the original (raw) data for the reviewer's evaluation.
  Transcripts of the original raw data may be submitted if they
  provide all of the information available in the original,
  including comments or notes of the investigator.


III.  REVIEWER'S EVALUATION

       The reviewer should identify each aspect of the reported
  procedures and determine if there is any inconsistency  with
  recommended methodologies.  The number of deviations and their
  severity will determine the validity of the study and the
  interpretation of the results.

       A.  Verification of Statistical Analysis        '

       Reviewer should ensure that a maximum allowable toxic
  concentration (MATC)  has been properly derived by recalculating
  the reported  "results.  If the recalculated results  differ
  substantially from the submitted results, the reviewer  should
  no.te this and attempt to explain the differences.

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     B.   Conclusions

          1.   Categorization of Results

     The significance of inconsistencies in the test procedures
must be  determined by the reviewer so that the results of the
test can be categorized as to whether they fulfill Part 158
regulations and are useful in performing a risk assessment.
Categories are described as:

     °  Core;   All essential information was reported and the
        study  was performed according to recommended protocols.
        Minor  inconsis.tencies with standard methodologies may
        be apparent; however, the deviations do not detract
        from  the study's soundness or intent.  Studies within
        this  category fulfill the basic requirements of current
        guidelines and are acceptable for use in a risk
        assessment.

     0  Supplemental:  Studies in this category are scientifi-
        cally  sound; however, they were performed under condi-
        tions  that deviated substantially from recommended
        protocols.  Results do not meet guideline requirements;
        however, the information may be useful in a risk
        assessment.

        Some of the conditions that may place a study in a
        supplemental category include:

          —  Unacceptable test species;
             inappropriate test material; or
             Deviations from recommended test solution charac-
             teristics (variations in DO, temperature, hardness,
             and pH can affect toxicological response),

     0  Invalid;  These studies .provide no useful information.
        They may be scientifically unsound, or they were
        performed under conditions that deviated so significantly
        from  recommended protocols that the results will not be
        useful in a risk assessment.

        Examples of studies placed in this category commonly
        include those where the test system was aerated, test
        vessels were constructed from materials other than
        glass, or there were problems of solubility or volatility
        of the test material.  Unless acceptable chemical.
        analyses of actual toxicant concentrations were performed
        in studies such as these, the reviewer cannot be sure
        that  test organisms were actually exposed to nominally
        designated concentrations.

        A study where the test material was not properly
        identified can also be'invalidated,

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                              -11-
          2.  Rationale

     Identify what makes the study supplemental or invalid.
While all- deviations from recommended protocol should be noted,
the reviewer is expected to exercise judgment in the area of
study categorization.

          '3.  Reparability         ,    ,.     .

     Indicate whether the study may be upgraded or given a
higher validation category if certain conditions are met.
Usually this would involve the registrant submitting more data
about the study.                            .            v

          ' ^*  Descriptive Conclusions  '     .    '

     The reviewer should indicate what' the results were and
how much, information can be drawn from them. - These results are
useful in a risk assessment.       •             •    .     .

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                             -12-


                          REFERENCES
(I)  ASTM Standard E 729-80, Practice  n,r Conducting  Acute
     Toxicity Tests with Fishes, Mac* " ! iw^r tebrates   and
     Amphibians.  American Society fo«- Tent-inn  Br1j L  ..   .  ,
     1916 Rac* street, Philadelphia, PA  19103?   ^ Materials,
(2}   Benoit, D.A.  (1981)  User's
     Chronic Toxicity Tests with
     promelas).  Environ. Res. Lab.-m, j „,.,
     600/8-81-011,

(3)   Hansen, D.J.; Parrish, P.R. ; Sch iltltflfl,
     (1978)   Toxlclty Test Using Sheet,,hq-
     var j.egatus) .  Bioassay Procedure^  r0r I-HB noo3»  ni^^L^ii
     Permit  Program.   EPA-600/9-78-OK,. °r the °Cean  DlsP°sal

(4)   Smith,  W.E.  (1976)  Larval Feed 1 ny  and       Maturation
     of Bluegill in the Laboratory.   fro,.  ri=h-riii*-   TR-
     95-97 pp.                                   cult.  j».
(5)   Sneed,  K.E, ,  H.P. Clemens   (1960)  ,,8ft  f pi h  PituitarieB
     to induce Spawning in Channel CatfUh"  u S  Pish  and
     Wildlife Service, Washington, DC,  %«cial scientific
     Report  - Fisheries No. 329.  12 pp.

(6)   Garten, R.R.   (1980)   A Simple Cont Inuou.-Plow  Toxicant
     Delivery System.   Water Res. i^-y,Ji7-y^
(7)   Mount,  D.I ,  Brungs, w.A.   (1967)  A gimplified  Dosi
     Apparatus for Fish Toxicology Stu
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