Series 162-1

 Aerobic Soil Metabolism Studies

           Prepared by:

        Samuel M. Creager
        E. Brinson Gonerly
    Exposure Assessment Branch
    Hazard Evaluation Division
            Edited by:

          Anne Bradford
    Exposure Assessment Branch
    Hazard Evaluation Division
         Project Manager:

    Elizabeth M.K. Leovey, PhD
    Hazard Evaluation Division
   Office of Pesticide Programs
US Environmental Protection Agency

       Subdivision N - Aerobic Soil Metabolism Studies

                Table of Contents of Addendum

Discussion                                               Page

Introduction                                               2

Response to Public Comments                                2


       Title/Cover Page                                    5

       Table of Contents                                   5

   I.  Abstract                                            5

  II.  Introduction                                        6

 III.  Materials/Mettods                                   6

  IV.  Results/Discussion                                  8

   V.  Conclusions                                         8

  VI.  Certification                                       8

 VII.  Tables/Figures                                      8

VIII.  References                                          8

  IX.  Appendix(es)                                        9


                               ENVIRONMENTAL FATE

                        Aerobic Soil Metabolism Studies

                          Subdivision N, Section 162-1

                                 DATA REPORTING

      A.   Purpose

           Information from this study enables the Agency to determine what
           the aerobic soil metabolism rate and metabolic products are for
           the pesticide.  The information is used to predict the likelihood
           of the compound persisting in the environment, and also whether
           degradates of concern are likely to be produced and to persist.

      B.   Objective

           This Data Reporting Guideline (DRG) is designed to aid the
           petitioner/registrant in generating reports which are compatible
           with the Agency's review process.  Data submitters are encouraged
           to submit complete reports for efficient review by the Agency-
           PR Notice 86-5, effective on November 1, 1986 (available from
           the Office of Pesticide Programs, US EPA), pertains to the physical
           formatting of reports (which are referred to as "studies") and
           submittal packages.  Some of the requirements in PR Notice 86-5
           are mandatory.


     The purpose of this section is to acknowledge and address the concerns ex-
 pressed in the letters of comment received by the Agency in response to the
 public notice in FEDERAL REGISTER, Volume 51, No. 199, p.  36753, Oct. 15, 1986.

      This addendum to the Pesticide Assessment Guidelines [Subdivision N] is to
 be considered an all-encompassing document.  The Exposure Assessment Branch
 (EAB) has reviewed the comments submitted by the registrants and/or commit-
 tees in regard to the Data Reporting Guideline (DRG).  This Guideline is not
 intended to create new data requirements,  but to provide for consistent
 reporting of the necessary environmental fate data required to perform a
 scientifically sound hazard assessment.  This approach should eliminate
 most, if not all, of the recycling of submissions between EAB scientists and
 the registrant.

      This discussion has been arranged to consider the general comments referring
to environmental fate DRGs first, followed by the specific comments concerning
this DRG.

 General Comments

     1.   Comment on the location of a specific reporting item:

          Considering the need to maintain a consistent format, revisions were
          made to the DPS in response to these comments wherever possible.

     2.   Ingredient information from testing laboratories:

          It appears some sponsors do not make this information available to
          testing laboratories.  In such a situation, the sponsor bears the
          responsibility since he is submitting the data for registration.

     3.   Standard evaluation procedures (SEPs):

          SEPs are guidance documents which explain the procedures used to eval-
          uate environmental effects data submitted to the Office of Pesticide
          Programs.  They are also available from the National Technical In-
          formation Service.  This DRG is compatible with the Agency's review

     4.   Appendix(es) - Inclusion of published and previously submitted data:

          Previously submitted material, both published and unpublished, may be
          "resubmitted" by reference to Agency file numbers [e.g. Master Record
          Identification (MRID) number].  In the case of published work which
          has not been submitted before, it is prudent to submit a copy with
          the application rather than to assume availability in Agency files.

Study-Specific Comments

     1.   Comment - TABLE CF CONTENTS:

          Should the TABLE CF CONTENTS include the title of each table and
          figure or simply the page on which each section begins?


          Each table and figure should be listed specifically in the TABLE OF

     2.   Comment - Section I:

          The average temperature and temperature range should also be specified.


          We agree, and have made this modification.

     3.   Comment - Section III:

          The use of the word 'narrative' is incorrect and [it should] be deleted
          or rewritten to convey the intended meaning.


     We disagree, per the definition in Random House Collegiate Dictionary

4.   Comment - Section III:

     [Let] millicuries per millimole (mCi/mmol) and disintegrations per
     minute per microgram (dpm/ug) replace curies/mole and dpm/g... The
     millimole (or micromole) is more representative of the range of
     concentration used in studies [and] dpm/ug is preferred, as [it] is
     not only more generically accepted but also routinely used in
     calculations of pesticide concentration.


     The Agency has no objection to the units this commenter prefers.  In
     any case, units should be clearly specified and used consistently
     throughout a report.

5.   Comment - Test Method:

     Further clarification is needed on pesticide treatment of the soil.
     It is assumed that the request pertains to prior treatment incurred
     under normal agricultural practice.  If so, how historically inten-
     sive does the record need to be?


     The request refers to actual pesticide treatment of the actual test
     soil.  Ideally, test soil would have received no pesticide treatment
     for three to five years prior to the test.

6.   Comment - Analytical Method(s);

     The request for method validation, recovery and sensitivity data,
     quality control procedures and results, would appear to relate to
     unlabeled (i.e., "cold") methods of analysis involving GLC or HPLC.
     If so, it should be so stated.


     Method validation, sensitivity, recovery,  and quality control are not
     concepts limited to any specific method(s) of analysis.  Unless the
     method of analysis is a recognized standard method, the applicant
     should demonstrate that it actually measures what it is intended to

7.   Comment;

     Likewise, the inclusion of a "material balance" is not clearly
     understood and needs further clarification.


          "Material balance" is a description of how completely the starting
          material (usually, but not always, radiolabeled)  is recovered in the
          analyzed end products.  For further details,  see Subdivision N of
          the Pesticide Assessment Guidelines available from NTIS.

     8.   Comment;

          It is suggested that it be noted that figures and/or photographs are
          generally necessary only when specialized equipment is used.


          The Agency agrees.

     9.   Comment;

          Having a separate heading of TABLES/FIGURES may be confusing.
          ...[I]t ought to be noted that tables and figures can be presented
          within the text of the results and discussion or as a separate


          Small tables and figures which do not interrupt the flow of the
          text may be included in the main body of the report.  However,
          extensive tables of data, full page graphs,  etc.  are preferably
          placed in a separate section at the end.



     Title page and additional documentation requirements (i.e. requirements
     for data submission and statement of data confidentiality claims),
     if relevant to the study report, must precede the content of the study
     formatted below.  These requirements are described in PR Notice 86-5.


     This page should indicate the overall organization of the study and what
     material is on which page(s).  Tables and figures should be listed in the
     table of contents.


     This section should contain the overall summary of the study and mention
     at least the following points:

     A.   The soil metabolism of the pesticide (use the name of the pesticide
          used throughout the report) was studied according to the general
          protocol of the Guidelines;


       B.   Indicate the site of radiolabeling,  if relevant;

       C.   Indicate the concentration(s) of the pesticide studied;

       D.   Indicate the soils in which the metabolism was conducted;

       E.   Indicate that the study was conducted in darkness;

       F.   Indicate half-life estimates for parent and significant  degradates;

       G.   Indicate the identity of the metabolic productsi  and what  percent of
            the initial pesticide concentration  they each represent  when
            analyzed throughout the study;

       H.   Indicate the sampling intervals; and

       I.   Indicate the temperature(s)  at which the study was  conducted,
            including average and range.


       This section should open with a description of the purpose of the study,
       what requirement it is intended to satisfy and (if applicable)  how it
       supports the position of the registrant.   Background and historical infor-
       mation relative to the study should be placed in this  section.


       The applicant may elect to describe materials and methods in  separate
       sections or combine into a single section.   The instructions  below combine
       the two into one section.

       This section should be in narrative form.  All details with regard to the
       materials,  equipment,  experimental design,  and procedures used  in con-
       ducting the study should be placed in this section. If  the study was done
       in several  phases, e.g. preliminary ("range-finding")  and definitive,
       describe each phase in detail.   In addition,  the following are  to be
       included, when appropriate:

       A.   Chemical

            1.  Provide the chemical purity of the material,  and state method of
                analysis if appropriate.

            2.  If radiolabelled material is used, then provide the  chemical and
                radiochemical purity of  the material, its activity in  Curies/mole
                and disintegrations per minute per gram (dpm/g) or other specified
                standard units of radioactivity, the site of  radiolabelling,  the
                isotope used, and the source when appropriate.

       B.   Soils

            Describe the characteristics of the  soils used and  their sources.
            Include the following items:

     1.   Percentage of sand, silt, clay;
     2.   Percentage of organic natter;
     3.   pH;
     4.   Cation exchange capacity; and
     5.   Moisture capacity.

C.   Equipment

     The description of the experimental design and equipment used should
     be placed here.

D.   Test method

     1.   General

          The detailed description of the test method should be placed
          here.  For example:

          a.   The method of preparation of soils and apparatus used (such
               as sieves);

          b.   The set-up and arrangement of the test apparatus (such as
               biometer flasks, trapping solutions, and the like);

          c.   The method of adding the pesticide to the soil;

          d.   The method and technique of sampling the soil, handling the
               sample and, if applicable, storing the sample;

          e.   The intervals of sampling and the number of replicates

          f.   Precautions for assuring complete recovery and trapping of
               volatile parent compound and/or products;

          g.   The method of maintaining the temperature and darkness
               during the study;

          h.   The level of moisture maintained in the soil during the
               study and how it was maintained; and

          i.   The history of pesticide treatment of the soil.

     2.   Analytical Method(s)

          This should include the following data:

          a.   The full description of each method used in this study;
               the method validation data, recovery and detection limit
               data, quality control procedures and results, sample
               chronatograms, sample calculations and a material balance;
               the detailed description of the procedures used in prep-
               aration and handling of the sample throughout the method

                       (Note that methods for degradation products, when
                       appropriate, are included); and

                  b.   The identity of the instrumentation, equipment and reagents
                       used and the operating conditions of the instrumentation.


        A.   This section should contain the scientific results of the study.

        B.   The results of the analysis of the samples are to be placed in this

        C.   This section also should contain the derived/projected half-lives for
             the parent compound and, when applicable, the metabolic products.


        This section should contain the discussion of the degree and significance
        of the aerobic soil metabolism of the parent compound, and, when applic-
        able, the metabolic products.


        This should include:

        A.   Signatures of each of the senior scientific personnel responsible for
             the study; and

        B.   Certification by the applicant that the report is a complete and unal-
             tered copy of the report provided by the testing facility (except for
             changes in the title page as required by PR Notice 86-5).


        A.   Figures/photographs of the equipment used in the methods and flow
             diagrams of particularly complex extraction/clean-up procedures are
             to be included here.

        B.   This section should contain the table of structures and chemical
             names/designations for the parent compound and metabolic products
             discussed in the study.

        C.   Narrative and tables explaining the steps taken in identifying and
             quantifying the parent compound and degradation products should be
             presented here; also, any graphical presentations of the data
             (accompanied by the tables of the actual values from which the graphs
             were constructed).

        D.   Tables and figures should be numbered using arabic numerals for
             figures and roman numerals for tables.



      At the registrant's option, reprints of methods and other studies cited,
      raw data, graphs, printouts, calculations, copies of relevant letters/
      memos and material not fitting in any of the other sections should be placed