United States Prevention, Pesticides EPA712-C-08-021
Environmental Protection And Toxic Substances October 2008
Agency (7101)
&EPA Fate, Transport and
Transformation Test
Guidelines
OPPTS 835.6200
Aquatic (Sediment)
Field Dissipation
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INTRODUCTION
This guideline is one of a series of test guidelines that have been
developed by the Office of Prevention, Pesticides and Toxic Substances
(OPPTS), United States Environmental Protection Agency for use in the testing
of pesticides and toxic substances, and the development of test data to meet the
data requirements of the Agency under the Toxic Substances Control Act (TSCA)
(15 U.S.C. 2601), the Federal Insecticide, Fungicide and Rodenticide Act
(FIFRA) (7 U.S.C. 136, et seq.), and section 408 of the Federal Food, Drug and
Cosmetic (FFDCA) (21 U.S.C. 346a).
OPPTS developed this guideline through a process of harmonization of
the testing guidance and requirements that existed for the Office of Pollution
Prevention and Toxics (OPPT) in Title 40, Chapter I, Subchapter R of the Code
of Federal Regulations (CFR), the Office of Pesticide Programs (OPP) in
publications of the National Technical Information Service (NTIS) and in the
guidelines published by the Organization for Economic Cooperation and
Development (OECD).
For additional information about OPPTS harmonized guidelines and to
access this and other guidelines, please go to http://www.epa.gov/oppts and
select "Test Methods & Guidelines" on the left side menu.
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OPPTS 835.6200 Aquatic (sediment) field dissipation
(a) Scope—(1) Applicability. This guideline is intended for use in meeting testing
requirements of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (7 U.S.C. 136, et
seq.). It describes procedures that, if followed, would result in data that would generally be of
scientific merit for the purposes described in paragraph (b) of this guideline.
(2) Background. The source materials used in developing this OPPTS test guideline are
OPP 164-2 Field dissipation studies for aquatic uses and aquatic impact uses, OPP 160-4 General
test standards, and OPP 160-5 Reporting and evaluation of data (Pesticide Assessment Guidelines,
Subdivision N - Chemistry: Environmental Fate, EPA report 540/9-82-021, October 1982)..
Additional guidance on properly designing field studies, including information on the conceptual
model approach to environmental testing, may be found in OPPTS 835.6100, Terrestrial field
dissipation.
(b) Purpose. The purpose of aquatic field dissipation studies for pesticides with aquatic and
aquatic impact uses is to determine the extent of dissipation and mobility of pesticide residues under
actual use conditions. Pesticide dissipation may proceed at a different rate in the aquatic
environment than in laboratory aquatic studies. These dissipation studies will generate on-site data
for evaluating potential hazards of a pesticide under actual use conditions, e.g., mobility, formation
of metabolites, and disappearance of parent compound, and provide information with respect to
mechanisms of dissipation in various aquatic environments.
(c) General considerations—(1) Data from aquatic field dissipation studies for end-use
products support aquatic food crop uses, aquatic non-crop uses, which include antifouling paints and
other outdoor protective uses where the pesticide-containing surface is in contact with water, and
also pesticide application to ditchbanks and shorelines, and any aquatic impact uses involving direct
discharge of treated water into outdoor aquatic sites. Such data may also support terrestrial uses
with potential for aquatic exposure if the chemical shows persistence, mobility, aquatic toxicity, or
bioaccumulation.
(2) Endangered species. Field studies should not be conducted in critical habitats or areas
containing or suspected to contain endangered or threatened plants or animals which may be
threatened by the test to be conducted.
(3) Environmental chemistry methods. Procedures and validity elements for independent
laboratory validation of environmental chemistry methods used to generate data associated with this
study can be found in 850.6100. Elements of the original addendum as referenced in 40 CFR
158.1300 for this purpose are now contained in 850.6100. These procedures, if followed, would
result in data that would generally be of scientific merit for the purposes described in 40 CFR
158.1300.
(d) Combined testing. Aquatic field dissipation testing may be combined with the field
accumulation studies in aquatic nontarget organisms, provided that the test standards for each study
are met.
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(e) Test method—(1) Test substance. The test substance should be a typical end-use
product.
(i) If the applicant's product is an end-use product, the test substance should be a product
whose formulation is typical of the formulation category (e.g., wettable powder, emulsifiable
concentrate, granular product) to which the product belongs.
(ii) If the applicant's product is a manufacturing-use product which could be used to make an
end-use product, the test substance should be a product representative of the major formulation
category which includes that end-use product. Except for antifouling paints and other related
protective-use products which fall into one formulation category, if the manufacturing-use product is
usually formulated into end-use products comprising two or more major formulation categories, a
separate study should be performed with a typical end-use product for each such category.
(2) Test sites. Aquatic field dissipation studies should be conducted in at least two different
sites which are representative of the areas where the pesticide is expected to be discharged or
applied. For restricted use patterns where only one typical area is involved, testing should be
performed at two similar sites. Studies should be performed in additional locations if the pesticide is
intended for an aquatic food crop use, and the sites of application vary in climate, terrain, or other
pertinent characteristics.
(3) Application. The test substance should be applied using the method of application stated
in the directions for use specified on the product label and at the highest rate recommended on the
product label. If the products are for use in pulp and paper mills or industrial cooling towers where
direct discharge of pesticide-treated water would be expected, sufficient test substance should be
applied to the receiving water in the study to produce the maximum concentration expected for each
discharge event.
(4) Sampling. Soil, sediment, and water samples serving as test controls should be obtained
from the intended sites of application or from direct aquatic discharges immediately prior to
application or discharge of the test substance, and to the extent possible from the adjacent untreated
areas, at intervals during the course of the study, and at the termination of the study. Soil, sediment,
and water from the treated area should be sampled following treatment for the purpose of
ascertaining the extent of pesticide dissipation in accordance with the following:
(i) Sampling times should include pre-application (control), date of application, and
immediate post-application for each single or multiple application of the test substance.
(ii) For aquatic food crop uses, soil and water should be sampled.
(iii) For aquatic non-crop uses, soil sediment and water should be sampled.
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(iv) For aquatic impact uses resulting in direct discharges, sediment and water should be
sampled.
(v) Soil should be sampled in increments to a depth of 15 cm.
(vi) Sediment should be sampled in increments to a depth of 5 cm.
(vii) Water should be sampled to a depth dependent upon the use patterns of the pesticide and
the site of pesticide action in water (bottom, surface, etc.), and flow meters or comparable techniques
should be used to measure water flow.
(5) Test duration. Residue data should be collected until patterns of decline of the test
substance and patterns of formation and decline of degradation products are established in the media
samples, or to the maximum time specified below for all use patterns in representative areas,
whichever comes first.
(i) Aquatic food crop uses: maximum test duration should be 12 months after application for
soil sampling and one month after application for water sampling.
(ii) Aquatic non-crop uses (all use patterns):
(A) Maximum test duration for sediment sampling should be six months for a single
application, and for multiple applications, the longer of the following: nine months after the first
application, or six months after the last application.
(B) The maximum test duration for water sampling should be one month following each
discharge event.
(iii) Aquatic non-crop uses (products intended for application to ditchbanks and shorelines
only): the maximum test duration for soil sampling should be six months for a single application,
and for multiple applications, the longer of the following: nine months after the first application or
six months after the last application.
(iv) Aquatic impact uses resulting in direct discharges:
(A) The maximum test duration for sediment sampling should be six months following a
single discharge event, and following multiple discharge events, the longer of the following: nine
months after the first discharge or six months after the last discharge.
(B) The maximum test duration for water sampling should be one month following each
discharge event.
(6) Protocol Development. Demint et al (paragraph (g)(2)) describes a procedure for
residues in crops irrigated with water containing trichloroacetic acid. J. Agr. Food Chem. 23:81-84.
Rice et al (paragraph (g)(3)) and Schaefer and Dupras (paragraph (g)(4) describe small-scale
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technique for persistence of dichlobenil in a farm pond. J. Agr. Food Chem. 24: 733-739
Information is also presented in paragraph (g)(3) on background interference and pesticide recovery
from soil and water.
(f) Reporting and evaluation of data. Reporting units should be in the metric system, but
the English system may be used in addition. The systems should not be mixed (e.g.,
kilograms/acre).
(1) Test method. A statement regarding the test method used, including a full description of
the experimental design and procedures.
(2) Test substance. The test substance should be identified including: (i) Chemical name
and percentage of active ingredient, molecular structure of the active ingredient, and qualitative and
quantitative description of the chemical composition, and the names and quantities of known
contaminants and impurities.
(ii) Manufacturer and lot and sample numbers of the test substances.
(iii) Properties of the test substance, including physical state, pH, and stability.
(3) Control values. Due to the wide diversity of pesticide properties, use patterns, and
organisms likely to be exposed in the field environment, specific reporting elements for control
values (as to source, sampling regime, and total number submitted) will depend upon the complexity
and variability of the environment in which the test is to be conducted.
(4) Test equipment. A description of the test equipment used, and photographs or detailed
descriptions of nonstandard equipment.
(5) Water. Characteristics of water obtained from a use site should be reported (e.g., pH,
temperature, oxygen content, flow rate, and percent suspended solids).
(6) Soils. Characteristics of soils/sediments should be reported, including texture (percent
sand, silt, and clay), percent organic matter, moisture content, pH, cation exchange capacity, and
bulk density (under field conditions).
(7) Dates of planting and harvesting. Dates of planting and harvesting of crops, if
applicable.
(8) Application times. Dates and times of pesticide application.
(9) Application methods. Description of application methods.
(10) Sampling techniques. Description of sampling techniques.
(11) Sampling times. Dates and times of sampling.
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(12) Crops and pest development. Dates and stages of crop and pest development, if
applicable.
(13) Treatment intervals. Application-to-harvest (if applicable) and application-to-sampling
intervals for each treatment.
(14) Sampling characteristics. Depth, weight, or volume of each sample, and weights and
volumes of aliquots taken for analysis.
(15) Flow data. Flow data expressed in terms of volume or linear flow.
(16) Decline curves. Decline curves of residues in each major substrate analyzed.
(17) Analysis and identification of degradation products. Analysis and identification of
pesticide residues in field studies should be reported only for those degradation products that were
found to form in the laboratory studies. This position is taken because the purpose of field studies is
to derive levels of degradation products as a result of pesticide use under field conditions.
(18) Calculation and tabular, graphic information. The principal mathematical equations
used in generating and analyzing data, as well as representative calculations using these equations.
When rates of formation and decline of parent compounds or their degradates are reported in any
test, data should be expressed as amounts, concentrations, and corresponding percentages. Rate
constants, when appropriate, should be reported in conjunction with rate data. Tabular data, as well
as graphs for decline curves and soil sorption, should be submitted.
(g) References. The following references should be consulted for additional background
information on this guideline:
(1) U.S. Environmental Protection Agency, (2008). OPPTS 850.6100 Independent
Laboratory Validation of Environmental Chemistry Methods.
(2) Demint, R.J., J.C. Pringle, Jr., A. Hattrup, V.F. Bruns, and P.A. Frank. 1975.
Residues in crops irrigated with water containing trichloroacetic acid. J. Agr. Food Chem. 23:
81-84.
(3) Rice, C.P., H.C. Sikka, and R.S. Lynch. 1974. Persistence of dichlobenil in a farm
pond. J. Agr. Food Chem. 24: 733-739.
(4) Schaefer, C.H., and E.F. Dupras, Jr. 1976. Factors affecting the stability of dimilin in
water and the persistence of dimilin in field waters. J. Agr. Food Chem. 24: 733-739.
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