PESTICIDE ASSESSMENT GUIDELINES
SUBDIVISION N
CHEMISTRY:
ENVIRONMENTAL FATE
Series 163-1
Leaching and Adsorption/Desorption Studies
ADDENDUM 6 ON DATA REPORTING
Prepared by:
Samuel M. Creeger
and
E. Brinson Conerly
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
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Subdivision N - Leaching and Msorption/Desorption Studies
Table of Contents of Addendum
Discussion Page
Introduction 2
Response to Public Comments 2
Guideline
Title/Cover Page 5
Table of Contents 5
I. Abstract 6
II. Introduction 6
III. Materials/Methods 7
IV. Results/Discussion 9
V. Conclusions 9
VI. Certification 9
VII. Tables/Figures 9
VIII. References 9
IX. Appendix(es) 10
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PESTICIDE ASSESSMENT GUIDELINES
ENVIRONMENTAL FATE
Leaching and Adsorption/Desorption Studies
Subdivision N, Section 163-1
DATA REPORTING
INTRODUCTION
A. Purpose
Information from this study enables the Agency to determine the
mobilities of the pesticide and its degradates. The information
is used to predict the likelihood of the compound and degradates
moving in the environment, in particular, the potential for ground
water contamination.
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 sutmittal
packages. Some of the requirements of PR Notice 86-5 are mandatory.
RESPONSE TO PUBLIC COMMENTS
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
concerning environmental fate DRGs first, followed by the specific comments.
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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 DRG 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
procedures.
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 OF CONTENTS:
Should the TABLE OF CONTENTS include the title of each table and
figure or simply the page on Which each section begins?
Response;
Each table and figure should be listed specifically in the table of
contents.
2. Comment;
In Section I.D., please explain what is meant by an aged soil thin-
layer study.
Response;
The aging refers to the pesticide in the soil. The test pesticide
may be applied to the soil, aged, extracted, and a thin-layer analysis
done on the extract. This procedure is intended to identify and
characterize both degradates and parent.
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3. Comment;
Please explain what an aged adsorption/desorption study is.
Response;
The aging refers to the pesticide in the soil. The test pesticide
may be applied to the soil, aged, extracted, and adsorption/desorp-
tion testing done on the extract; or, alternatively, applied to the
soil, aged, and the batch adsorption/desorption done. This procedure
is intended to identify and characterize both degradates and parent.
An aged batch adsorption/desorption study may be used to fulfill the
requirement for data on mobility of the aged pesticide, although an
aged column leaching study would be acceptable.
4. Comment - Section III;
The use of the word 'narrative' is incorrect and [it should] be deleted
or rewritten to convey the intended meaning.
Response;
We disagree, per the definition in Random House Collegiate Dictionary
© 1973.
5. Comment - Section III:
[Let] millicuries per millimole (mCi/mmol) and disintegrations per
minute per micrcgram (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.
Response;
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.
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.
Response;
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
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should demonstrate that it actually measures what it is intended to
measure.
7. Comment:
Likewise, the inclusion of a "material balance" is not clearly
understood and needs further clarification.
Response;
Material balance" is a measure of how completely the starting
material (usually, but not always, radiolabelled) is recovered in the
analyzed end products. For further details, see Subdivision N of
the Pesticide Assessment Guidelines available from OTIS.
8. Comment;
It is suggested that it be noted that figures and/or photographs are
generally necessary only when specialized equipment is used.
Response;
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
section.
Response;
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.
GUIDELINE
TITLE/COVER PAGE
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.
TABLE GF CONTENTS
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.
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I. ABSTRACT
This section should contain the overall summary of the study and mention
at least the following points:
A. The soil leaching potential of the pesticide (use the name of the
pesticide used throughout the report) was studied by one of the
methods cited in the Guidelines (column leaching, soil thin-layer
or adsorption/desorption) and indicate whether unaged or aged.
B. Indicate the site of radiolabeling, if relevant.
C. If the column leaching method was selected, then indicate the classes
of soil studied, how much pesticide was applied to the top of each
column (in terms of milligrams and pounds active ingredient per
acre), how much water was applied to the top of each column (in
terms equivalent to acre inches), the distribution of the pesticide
residues through the columns after elution (in terms of percent of
applied pesticide per segment of the column) and what percent of
the applied was found in the leachate. In this section, also
provide the identity of the residues found in the columns and
in the leachate in terms of percent of pesticide initially found.
In the aged column study, provide the above plus the initial con-
centration of the pesticide in the soil that is being aged, the
length of the aging period, the weight of the treated, aged soil
aliquot taken to overlay the untreated soil column and the con-
centration of residues in the aged soil aliquot after the aging
period.
D. If the soil thin layer method was selected, then indicate the
classes of soil studied, the thickness of the soil layer on the
plates, how many micrcgrams of chemical were spotted on each
plate, the distance of the elution front and the calculated Rf
values.
In the aged soil thin layer study, provide the above plus the con-
centration of the chemical in the soil that is being aged, the length
of the aging period and the method in applying the aged residues
to the untreated soil thin layer plate.
E. If the adsorption/desorption method was selected, then indicate the
classes of soils studied, the concentrations of pesticide studied,
and the K^ values obtained.
In the aged adsorption/desorption study, provide the above plus the
concentration of the pesticide in the soil that is being aged, the
length of the aging period and a brief description of the method
of removing the soil aged residues from the soil.
II. INTRODUCTION
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
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supports the position of the registrant. Background and historical infor-
mation relative to the study should be placed in this section.
III. MATERIALS/METHODS
Materials and methods may be described in separate sections if desired.
The instructions below are for a single section combining the two.
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. The chemical and radiochemical purity of the pesticide, the
site of radiolabeling, and the activity of the pesticide in
Curies/mole and disintegrations per minute per gram (dpm/gm)
or other standard specified units are to be reported here.
If non-radiolabeled pesticide was used, the composition of
the test material should be reported here.
2. The source, purity and/or composition of the water or sol-
ution used for eluting/partitioning is to be reported here.
B. Soils
The soils used in the imaged and aged leaching studies are to be
described in this section by listing the following:
1. Percentage of sand, silt, clay;
2. Percentage of organic matter;
3. pH;
4. Cation exchange capacity;
5. Source; and
6. Textural class — e.g. "sandy loam".
C. Equipment
The description of the experimental design and equipment used should
be placed here, especially column design and assembly, the soil
thin layer plate material and developing tank, or equipment used
in the adsorption/desorption.
D. Test method
1. General
The detailed description of the test method should be placed
here. For example:
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a. Any preparation (such as sieving) or modification (such
as milling) done to the soil;
b. How the soil column and soil thin layer plates were
prepared;
c. How the soil was aged for the aging studies;
d. How the chemical was applied to the soil, the description
of the elution or partitioning process, how long elution
took or how much time was allowed for soil-water partition-
ing equilibrium to be reached;
e. For the column studies, the description of the soil extru-
sion process, soil column sectioning and other preparations
for sampling of both the soil and leachate for analysis;
f. For the soil thin layer studies, a description of the proc-
edures used for developing the treated soil thin layer
plate, visualizing the developed spots on the soil thin
layer plate and, if applicable, scraping the spots for
analysis;
g. For the adsorption/desorption studies, a description of how
the soil was treated with pesticide, how the partitioning
process was initiated and how the soil and water phases were
separated and prepared for analysis;
h. The descriptions of the dates and conditions under which
the soil and leachate samples were stored and the thawing
procedure (if frozen), in addition to the storage stability
data;
i. How long samples will be retained and under what conditions
they will be retained (in case additional work is needed);
and
j. What special problems or difficulties arose during the
study that necessitated deviation from the intended test
protocol and the effects the deviations had on the results.
2. Analytical Method(s)
a. The full description of each method used in this study
should be placed in this section. This should also include
appropriate method validation data, recovery and detection
limit data, quality control procedures and results, sample
chromatograms, sample calculations and a material balance.
The detailed description of the procedures used in prep-
aration and handling of the sample throughout the method
should also be placed here. Note that methods for degrad-
ation products, when appropriate, are included.
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b. The identity of the instrumentation, equipment and reagents
used and the operating conditions of the instrumentation
should be placed here.
IV. RESULTS/DISCUSSION
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
section.
C. This section also should discuss the leaching potential of the parent
compound and, when applicable, the degradative products arising
during aging.
V. INCLUSIONS
This section should contain the discussion of the degree and significance
of the leaching potential of the parent compound, and, when applicable,
the degradative products.
VI. CERTIFICATION
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 title page changes required by PR Notice 86-5).
VII. TABLES/FIGURES
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 degradative products
discussed in the study.
C. Narrative and tables explaining the steps taken in identifying and
quantifying the parent compound and products should be presented here
in addition to any graphical presentations of the data (accompanied
with 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.
VIII. REFERENCES
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IX. APPENDDC(ES)
This is optional. You may attach graphs, raw data, printouts, calcula-
tions, and the like, which nay further support the study. Reprints of
methods ard other studies, raw data, copies of relevant letters/memos and
material not fitting in any of the other sections should be placed here.
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