EPA-540/9-82-021
October 1982
Pesticide Assessment Guidelines
Subdivision N
Chemistry:
Environmental Fate
Prepared by Staff of
Environmental Fate Branch
Hazard Evaluation Division
Office of Pesticide Programs
Guidelines Coordinator
Robert K. Hitch
Hazard Evaluation Division
Office of Pesticide Programs
U.S. Environmental Protection Agency
Office of Pesticides and Toxic Substances
Washington, D.C. 20460
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SPA ^
October 18, 1982
PESTICIDE ASSESSMENT? GUIDELINES
SUBDIVISION N
CHEMISTRY:
ENVIRONMENTAL FATE
by Staff of
Environmental Fate Branch
Hazard Evaluation Division
Office of Pesticide Programs
Guidelines' Coordinator
Robert K. Hitch
Hazard Evaluation Division
Office of Pesticide Programs
O.S. Environmental Protection Agency
Office of Pesticide and Toxic Substances
Washington, D,C. 20460
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Foreword
Subdivision N describes protocols vMch may be used to perform
environmental fate testing to support the registration of pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).
It is a non-regulatory companion to 40 CFR Part 158, Data Require-
ments for Registration. A public meeting was held in July, 1982 to
accept conments on the FIFRA guidelines. Because of the importance of
the issues raised in the Subdivision N comments, a review conmittee
comprised of representatives of industry, environmental groups and
academia read and approved the Agency revision. This guideline refers
to requirements established in 40 CFR Part 158 so that this document can
be read as a complete package and so that the protocols may be explained
in their proper context.
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Subdivision N
ENVIRONMENTAL FATE
Table of Contents
Discussion
I. Organization and Philosophy 1
II. Response to Public Comment 9
A. General Information and Requirements 9
B. Benchmark Concept 13
C. Degradation Studies . .14
D. Metabolism Studies 18
E. Pesticide Residue Mobility Studies 21
F. Dissipation Studies; Combination Products and
Tank Mixtures 23
G. Accumulation Studies 23
H. Sections of 1978 Proposal to be Issued as
Separate Subdivisions 27
I. Appendix to 1978 Proposal 28
Guidelines
Chemistry Requirements: Environmental Fate
§ 160 General Information and Requirements .30
§ 160—1 General Information 30
§ 160-2 Definitions 35
• ' § 160-3 . Use Pattern 37
§ 160-4 General Test Standards 39
§ 160-5 Reporting.and Evaluation of Data 41
§ 161 Degradation Studies 44
§ 161-1 Hydrolysis Studies 44
§ 161-2 Photodegradation Studies in Water 46
§ 161-3 Photodegradation Studies on Soil 49
§ 161-4 Data for Photodegradation Studies in Air 52
§ 162 Metabolism Studies 54
§ 162-1 Aerobic Soil Meatbolism Studies 54
§ 162-2 Anaerobic Soil Metabolism Studies 57
§ 16Jr3 Anaerobic Aquatic Metabolism Studies 59
§ 16Jt^-4 Aerobic Aquatic Metabolism Studies 62
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§ 163 Mobility Studies 64
§ 164
§ 165
§
$
§
163-1
163-2
163-3
Leaching and Adsorption/Desorption Studies
Laboratory Volatility Studies
Field Volatility Studies
64
71
74
Dissipation Studies
!
§
§
!
§
164-1
164-2
164-3
164-4
164-5
Field Dissipation Studies for Terrestrial Uses
Field Dissipation Studies for Aquatic Uses and
Aquatic Impact Uses
Dissipation Studies for Forestry Uses
Dissipation Studies for Combination Products
and Tank Mix Uses
Long Term Soil Dissipation Studies
Accumulation Studies
§
§
§
§
165-1
165-2
165-3
165-4
Confined Accumulation Studies on Rotational
Crops
Field Accumulation Studies on Rotational Crops
Accumulation Studies , on Irrigated Crops
Laboratory Studies of Pesticide Accumulation
78
81
85
89
91
95
95
97
101
103
in Fish
§ 165-5 Field Accumulation Studies of Aquatic ,
Non-Target Organism 107
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1
I. ORGANIZATION AND PHILOSOPHY
A. Purpose
The data generated by the environmental fate studies described
in these guidelines are used by the Agency, along with other data,
to assess the hazards posed by use of a pesticide product, in order
to determine whether the product should be registered. In particular,
the Agency needs these data to assess;
(1) Direct consequences to man through exposure to pesticide
residues remaining after application, either upon
reentering treated areas or frcm consuming inadvertently-
contaminated food?
(2) Indirect consequences to man from the presence of widely
distributed and persistent pesticide residues in the
environment which may result in loss of usable land,
water, and wildlife resources; and
(3) Potential environmental exposure of other nontarget
organisms such as fish and wildlife to pesticide residues.
Another specific purpose of the environmental fate data
requirements is to help registration applicants and the Agency
estimate expected environmental concentrations of pesticides in
specific habitats where endangered species or other populations at
risk 'are found. ' '•'''••
Pesticides can be introduced into the environment by applica-
tion to water, soil, and air. Following introduction to any of
these media, pesticides may be transported from one medium to
another by processes that are partly influenced by the chemical
characteristics of the pesticide. Transport is also influenced
by physical forces in the environment such as meteorological condi-
tions, flow of surface water, location and flow of ground water,
tidal action, and topographic characteristics. The physical and
chemical characteristics of soil, sediments, particulates, and
water also influence the transport and fate of pesticides.
No single test scheme can predict precisely the length of time
a pesticide will remain in one particular location, or by what
mechanism and at what rate it will be transported, transformed, or
degraded. A test sequence at best can provide data which a skilled
evaluator can integrate with other information to provide a rough
estimate of the concentration of the pesticide and a tentative
conclusion about its persistence or rate of disappearance. On the
basis of such conclusions, the evaluator can often rule out the
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possibility of a pesticide entering certain environments at a
concentration that presents a significant risk to man and/or non-
target organisms. On the other hand, the pesticide nay enter
certain environments at a concentration that would present a
significant risk. In these situations, field monitoring studies
may provide the information necessary to evaluate the significance
of the risk to nontarget organisms.
B. approach
Proposed rule, 40 CFR Part 158, specifies the kind of data and
information that must be submitted^to SPA to support the registra-
tion of each pesticide under the Federal Insecticide, Fungicide
and Rodenticide Act. The Agency intends to promulgate Part 158 as
a final rule during 1983. This subdivision provides detailed
information that should be included in a test report.
The guidelines also describe circumstances under which an
applicant should consult with the Agency before initiating a test.
In addition, the references Specified in these guidelines provide
useful information for designing test protocols and, in some cases,
examples for acceptable protocols for conducting the required testing*
The sections of this subdivision of the guidelines have been
reorganized since they were proposed as rulemaking in 1978. The
following description of the section series, complete with new
numbers and the corresponding numbering system as proposed July 10,
1978., will explain'this; reorganization* . • , • '-'•
Section 1SO-1 "General Information" (formerly § 163.62-1,
"Purpose: Hazard .Evaluation" and § 163.62-3 "Scope and Requirements*)
describes the purpose of the prescribed-environmental fate studies
as they relate to environmental hazard assessment. Two tables
have .been included which summarize the basic Part 158 environmental
fate data, requirements as they relate to intended use patterns of
a pesticide. ;
Section 160-2 "Definitions" {formerly § 163.62-2) contains
definitions of terms used in this subdivision.
Section 160-3 "Use Patterns" (formerly § 163.62-6 "Use Patterns
Associated With Data Requirements") categorizes use patterns of
pesticides intended for outdoor application.
Section 160-4 "General Test Standards" (formerly § 163.62-4
"Basic Standards for Testing") provides a discussion of the general
requirements for test design and test substances applicable to
most tests.
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Section 160-5 "Reporting and Evaluation of Data" (formerly
§ 163.62-5 "Reporting of Data") provides reporting requirements
that apply to most or all studies.
Section series 161 through 165 (formerly §§ 163.62-7 through
163.62-11) contain specific provisions pertaining to each of the
studies required to support the registration of manufacturing-use
and end-use products, lach of the five sections series pertains
to a single test or related group of tests.
Thus, §§ 161-1 through -4 (formerly § 163.62-7 "Data Require-
ments; Degradation") relate to physicoehemical degradation of
pesticides in the environment and describe data requirements for
studies of hydrolysis and photodegradation in soil, water, and
air. Pesticides introduced into water in the environment may
undergo hydrolysis (degradation of the pesticide as a. result of
interaction with water) and be transformed into new chemicals with
properties different from their precursors. The extent to which
this process occurs in water can be determined from quantitative
data on rate of hydrolysis and half-life determinations. Pesticides
introduced into water in the environment can also undergo transfor-
mation by photolysis (breakdown by sunlight) into new chemicals
with different properties than the original chemical. In certain
circumstances, photolysis can also be a major route of degradation
of pesticide.residues on soil or in the vapor.phase. Data on rate
of photolysis and halflives establish the importance of photolysis
in sunlight as a dominant.process in the transformation of pesti-
cides in water. The data generated from both hydrolysis; and
photolysis studies., are then used to determine: rate- of degradation
of the' pesticide .and identification of pesticide. residues' which
may adversely; affect nantarget organisms' in the environment.
Sections- 162-1 through -4 (formerly §163.62-8 "Data,Require-
ments! Metabolism") describe the Agency's requirements for data
related to metabolism, which will be used to assess- the persistence
of--a pesticide' in a 'natural environment.'- These data requirements
concern aerobic (in the presence of oxygen) and anaerobic (without
oxygen) soil metabolism/ and aerobic and anaerobic aquatic metabo-
lism. The data generated from the metabolism studies described in
this section are essential to determining the nature and avail-
ability of pesticide residues to rotational crops and to aiding in
the assessment of environmental hazards related to the persistence
of a pesticide in.the environment after its disposal.
Sections 163-1 through -3 (formerly § 163.62-9 "Data Require-
ments:. Mobility") describe the data requirements related to pesti-
cide mobility. The data generated from the studies required in'
§§ 1631 through--3 provide information regarding pesticide trans-
port and are used to assess potential environmental hazards related
to contamination of human and animal food, loss of usable land and
water resources to man through contamination of water (including
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ground water), and habitat loss to wildlife resulting from pesti-
cide residue movement or transport in the environment.
These data requirements pertain to leaching, adsorption/
desorption, and volatility of pesticides, and provide information
both as to the mode of transport and eventual destination of the
pesticide. For example, a pesticide with a high vapor pressure
relative to its sorptive tendency (i.e., water solubility, soil
absorptivity) is likely to volatilize from the medium where it
was applied. A pesticide with a low vapor pressure and relatively
high water solubility, in contrast, is more likely to leach through
the soil. Volatile chemicals are prime candidates for photolysis,
and therefore may cause the presence of photo-oxidants in the air
(atmosphere) or otherwise contribute to adverse atmospheric effects.
However, nonvolatile chemicals will either bind to the soil or
leach, depending on their affinity for particular surfaces and
their water solubility. Pesticides that adsorb tightly are gen-
erally less subject to environmental transport in the gaseous
phase or in solution and may accumulate in the soil. Substances
which1 are not tightly adsorbed, however, can be transported through
soils to aquatic systems and to the atmosphere*
Sections 164-1 through -6 (formerly § 163.62-10 "Data Require-
ments: Field Dissipation") establish requirements for data from
terrestrial, aquatic, aquatic impact, and forestry field dissipa-
tion studies. A pesticide combination and tank mix dissipation
study and a long term field dissipation study may also be required
under certain situations. The data generated'from the studies des-
cribed in these sections are used to assess-th6•potential environ-
mental hazards (under actual field use conditions) related to
reentry into treated areas,'-;hazards "from residues" in rotational'
crops and other food sources, and the loss- of land and water
resources. . ''.'"'' ; '': ' ' • ' ':ii" '
Sections 165-1 through -5 (formerly § 163.62-11 "Data Require-
ments: ccumulation") describe'data requirements for accumulation
studies. These studies deal with pesticide residue uptake and •
accumulation in rotational crops,- irrigated crops, and- fish. The
data generated from these studies are used as part of an assessment
of the potential adverse effects of these residues on nontarget
organisms. These data also reveal pesticide levels in food supplies
that originate from wild sources or from rotational crops. Rota-
tional crop studies are necessary to establish realistic crop
rotation restrictions (time from application to time when crops
can be rotated) and to determine if tolerances may be needed for
residues on such crops. Data'from irrigated crop studies are used
to determine the amount of pesticide residue taken'up by represen-
tative crops from irrigation water transported 'from some other
pesticide—treated area. These'studies will allow the Agency to
establish label restrictions regarding application of pesticides
in sites where the residues"can transport to irrigated crops,-
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These data will also provide information that will aid the Agency
in establishing any corresponding tolerances that would be needed
for residues on such crops. Data from pesticide accumulation
studies in fish are used to establish label restrictions (e.g., to
prevent applications in certain sites so that there will be minimal
residues entering edible fish or shellfish such as catfish or
crayfish inhabiting rice'fields). These residue data will also be
used to determine if any tolerance or action levels are needed for
residues in aquatic animals eaten by humans.
Proposed §| 163.62-12 "Data Requirements: Beentry" and 163.62-
13 "Data Kequirementst Disposal and Storage" were reserved in the
1978 proposed guidelines. Data requirements for reentry are now
treated in Subdivision K of these guidelines; disposal and storage
data requirements will be treated in Subdivision 1 (reserved).
References that appeared in the Appendix to the 1978 proposed
guidelines nave been carefully scrutinized for adequacy and useful-
ness. Some were deleted and several new references have been
added. All references now include explanatory annotations which
better describe the usefulness of each cited reference to the
registrant. In the revised guidelines the references have been
grouped according to subject matter and relocated at the end of
each section.
A listing of current sections and paragraphs in Subdivision
N and the equivalent former sections and paragraphs in the environ-
mental chemistry portion of Subpart D in the 1978 proposed guide-
lines appears in Table 1.
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Table 1. Location of current: and proposed guidelines.
Subject • . Current ' Proposed
GENERAL INFORMATION AND REQUIREMENTS
Purpose and scope of 160-1(a) 163.62-3
data requirements
Application of requirements -1(b) «.*«.
Approach of subdivision (subpart) -1(c3 -3(a)
Summary tables -1(d) -3 (a)
Organization and content -1(e) -3(b)
of sections
Definitions 160-2 163.62-2
Use patterns 160-3 163.62-6
General -3(a) 163.62-6
Terrestrial uses -3(b) -6(a)
Aquatic uses -3(c) -6(b)
Aquatic impact uses -3(d) -6(c)
Forestry -3(e) -6(d)
General test standards 160-4 163.62-4
Overview -4(a) .....
Personnel -4(b) -4(a)
Test controls -4(c) -4(b)
Test substance -4(d) -4{c)
Field studies -4(e) -4(d)
Inter-relationship between . -4(f) .....
studies with respect to
soil 'type ,
Reporting and evaluation 160-5 163.62-5
of data • ' '
Overview -5(a) ......'
Nature of submission -5(b) -5(a)
Content -5(c) -5(b}»(c)
Content (data evaluation} -5(e)(10) 163.62-1(a),(b)
DEGRADATION STUDIES
General 163.62-7(a)
Hydrolysis studies 161-1 -7(b)
Photodegradation studies -2 -7(c)
in water
Photodegradation studies -3 -7(c)
in soil
Photodegradation studies -4 -7(c}
in air
METABOLISM STUDIES
General 163.62-8(a)
Aerobic soil metabolism 162-1 -8(b)
studies
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Table 1. (continued)
Anaerobic soil metabolism
studies
Anaerobic aquatic metabolism
studies
Aerobic aquatic metabolism
studies
Microbial metabolism
General
Effects of microbes on
pesticides •
Effects of pesticides on
microbes
Activated sludge metabolism
MOBILITY STUDIES
General
Leaching studies
Laboratory volatility
'studies
Field volatility studies
Adsorption/desorption
Water dispersal
DISSIPATION STUDIES
General
Field dissipation studies
for terrestrial 'uses
Field dissipation studies
for aquatic uses and
aquatic impact uses
Specialized aquatic uses
Dissipation studies for
forestry uses
Aquatic impact uses
Direct discharge
Indirect discharge
Wastewater treatment
Dissipation studies for
combination products
and tank mix uses
Long-term soil dissi-
pation studies
ACCUMULATION STUDIES
General
-2
-3
-4
163-1
164-2
164-1
161-1,-2
162-3,-4
163-1
164-2
165-4,-5
161-1
164-4
-5
-8(c)
-8(d)
-8(e)
-8(f)
-8(f)(3)
-8(g)
163.62-9(a)
-9(b)
-9(c)
-9(c)
-9(d)
-9(e)
163.62-10(a)
-10(c) 3)
-1-0 (f)
163.62-11 (a)
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Table 1, (continued) f:
Lab/greenhouse/small plot 165-1 -11(b)
accumulation studies
for rotational crops
Field accumulation studies -2 -11(b)
on rotational crops
Accumulation studies on -3 -11(c)
irrigated crops
Lab studies of pesticide -4 -11{d)
accumulation in fish
Field accumulation studies in -5 -11(e)
aquatic noritarget organisms
REENTRY {Subdivision K) 163.62-12
DISH3SAL AND STORAGE ' (.Subdivision-P) 163.62-13
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II. RESPONSE TO PUBLIC COMMENT
The Agency received comments from 63 commenters regarding the
1978 proposed environmental chemistry guidelines. In many cases,
the commenters provided amended test protocols for consideration by
the Agency and provided references or background material. In
response to the public comments, the Agency has modified or clarified
many sections of the guidelines. For purposes of this discussion,
only the more significant and controversial issues reflected by
public comments are discussed. Many minor recommendations which do
not warrant discussion here were adopted by the Agency.
A. General Information and Requirements.
.1. Data requirements for manufacturing-use products. In the
Preamble to the 1978 proposed Guidelines, EPA asked for public
comment on the question whether the data requirements of this
subdivision should be extended to manufacturing-use products.
After serious consideration of this issue, the Agency has con-
cluded that extending the data requirements to such pesticides is
appropriate. The Agency was influenced by the views of commenters
on this issue who generally favored a data submission requirement
which makes the basic manufacturer of an active ingredient respons-
ible for providing most of the environmental fate data.
Therefore, a section of 40 CFR Part 158, entitled "Formulators'
Exemption" (§ 158.50), requires'a registrant of a manufacturing-use
product to submit (or cite) any data pertaining to the safety of an
active ingredient in its product if the same data are required to
support the registration of an end-use -product that could legally
be produced from the. registrant's manufacturing-use products. (An
end-use product is a pesticide product bearing label directions for
immediate end-use as. a pesticide)* Section 158.50 also provides
that such data must be submitted by an applicant for registration
of the. end-use product, except that the producer of the end-use
product will generally not have to submit or cite data pertaining
to registered products which the end-use producer purchases and
uses to formulate the end-use product. This decision reflects the
Agency's expectation that manufacturing-use product registrants
will be the major source of registration data, and that end-use
product femulators will, in most cases, need to supply much less
data. This decision is consistent with the provisions of, and
Congressional intent behind, sec. 3(c)(2)(D) of FIFRA, which pro-
vides that:
No applicant for registration of a pesticide who proposes
to purchase a registered pesticide from another producer
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10
in order to formulate such purchased pesticide into an
end-use product shall be required to—
(i) submit or cite data pertaining to the safety of
such purchased productj or
{ii), offer to pay reasonable compensation otherwise
required by [f 3(c)(1)(D) of FIFRA] for use of any such
•• • data. ; ...-. ..-,.....-. . .
Implicit in sec. 3(c).(2)(D) is Congress' expectation that it
would be the registrant of the manufacturing—use product who would
provide significant amounts of data pertaining to the safety of its
product. (See, e.g.. Sen. Rep. No. 334, 95th Cong., 1st Sess., pp.
8-9.)
Moreover, if data requirements were imposed solely on registrants
of end-use products, sec. 3(c)(2)(D) might be read to prevent the
Agency from obtaining data on the grounds that the data pertain to
the safety of a purchased product.
2. Clarification of Data and Test Substance Requirements
Many public comments revealed that the proposed guidelines
created confusion as to which registrants have an obligation to
submit data (the "data requirements") and what test substances
must be used to generate required data (the "test substance
requirements"). For example, several people commented that it
was 'unreasonable to require an aerobic soil metabolism study to
be performed with, all formulated products. Instead, they argued .
that EPA should require testing only -with the active ingredients
in.pesticide products. In fact, the proposed environmental fate.
guidelines did require use of the active ingredient, not-the '
formulated product, as the test substance in" aerobic soil metabo- •
li'sm studies. [See proposed § 163«62-8(b) and § 162 .8-4 (c) (1) (i)
of the FIFRA sec. 3 regulations.] Thus, the Agency concluded from
this .comment and many like it that there was~a:'need to clarify the
data requirements and test substance requirements in the environ-
mental fate guidelines. •
EPA has taken a number of steps to make;these requirements
clearer. First, the Agency has included many new definitions- and
additional explanatory material to clarify which-products are
covered by a particular use pattern. (See §§ 160-2 and 160-3.)
Specifically, EPA has issued a definition for'each of • the use
'patterns which serve as the basis for the environmental fate data
requirements. In addition, EPA has provided explanatory' material • in
§ 160-3 which gives numerous examples of specific uses which are
covered by the use pattern' definitions.
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11
Second, the Agency has added a section titled "Application
status and submittal times" to § 158.30 of 40 CFR f 158 which
specifies when data must be submitted for both full registration
and conditional registration [FIFRA sec.3(c){5) and 3(c)(7),
respectively].
Third, as discussed above, the Agency has addressed each
different study in a separate section of the guidelines. Each of
these sections now contains both a "When required" paragraph that
states which products must be supported by a particular kind of
data and who must submit such data, as well as a "Test substance"
paragraph that identifies the substance which must be used in ,
performing the study. Generally, the "When required" paragraphs
state that a particular test will be required for all end-use
products having a specific use pattern category, and for all
manufacturing-use products which nay legally be formulated into
such end-use products.
Finally, EPA has revised the Table of Use Patterns and Data
Requirements that appeared in the proposal. This table, which
originally appeared in § 163.62-3, has been divided into two tables
that are located in § 160-1 of the current guidelines. The first
table covers terrestrial uses and forestry uses, and the second
table covers aquatic uses and aquatic impact uses. It must be
noted that these tables are intended for quick reference and do not
include all data requirements and exemptions from data requirements
found in the "When required" paragraphs of the individual sections.
For example, Table 1 indicates that a photodegradation study on
soil is required to support the registration of' end—use products
with certain terrestrial uses. The table does not include the
provision in the "-When required" paragraph for that study which
excludes products injected into the soil or incorporated into soil
during application. Most of. the requirements which are not covered
by the tables are listed in an accompanying footnote,
3. Testing a representative end-use product. The Agency seeks to
avoid imposing a burden of duplicative testing on applicants for
registration. Therefore, where 40 CFR §158 specifies that the test
substance shall be a typical end-use product, testing may be
performed on a representative formulation. It is not necessary to
repeat the test using other similar products. A typical end-use
product is defined in §160-2(b)(23) as:
A pesticide product that is representative of a major
formulation category (e.g., emulsifiable concentrate,
granular product, wettable powder) and contains the
active ingredient of the applicant's product.
The use of a typical end-use product in environmental fate testing
is needed for tests which determine the extent of overall pesticide
dissipation under actual use conditions. In Subdivision N, all
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12
tests in §1S4 (dissipation studies) and sane in §165 (accumulation
studies) are in this category. Moreover, since manufacturing-use
products may be formulated into end-use products belonging to
several different formulation categories, testing is required with
a typical end-use product from each formulation category. Accord-
ingly, the test substance section of these tests now contains a
provision which states:
If the applicant's product is a manufacturing-use
product intended for [forestry use], the test sub-
stance shall be a product representative of the
major formulation category for that general use
pattern. (If the manufacturing-use product is
usually formulated into end—use products comprising
two or more major formulation categories, a separate
study must be performed with a typical end—use
product for each category.
4. Definitions. In the 1978 proposed guidelines, only one defini-
tion — "material balance"— was included for the data require-
ments pertaining to environmental fate studies* In the course of
clarifying and revising the subdivision, it became apparent that
major terms used -throughout the environmental fate sections needed
definition. In particular, definitions were needed relating to
pesticide use patterns. The four major use categories now employed
in the subdivision {terrestrial, forestry, aquatic, and aquatic
impact) are now defined, and all of the subcategories (e.g, orchard,
aquatic noncrop, etc.) are also defined. See § 160-2. Examples
of uses within these categories are provided in § -160-3 (Use Pat- "
terns)» .. ' .•• .';.'•' .' • . ' ' _ •.
5," •Personnel requirements. A number of conmenters raised objec-
tions to proposed § 163.62-4(a), which provided that:
All testing and evaluation must be done under
the direction of personnel-who have the
education, training and experience to perform
the testing and evaluation in accordance with
sound scientific' experimental' procedures. . - '
That section also provided that the Agency may request a resume of
the qualifications of personnel performing, supervising, reviewing
or evalimting testing. ' Most conmenters objected particularly to
the reference to a resume, and stated that if the Agency were to
have the opportunity to request resumes, the applicant should have
an opportunity to request a resume of the Agency reviewer to deter-
mine if the reviewer is qualified to review the data furnished.
It was also pointed out by one coamenter that the proposed provision
was overly broad in that testing is not always performed under the
direction of managers and supervisors who have the education,
training and.-experience to perform actual testing.
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13
In response to public comments, the Agency has withdrawn this
test standard.
6- Data requirements for small-package, low-toxicity pesticides.
Several commenters objected to the imposition of environmental fate
data requirements for small-package, low-toxicity pesticide products,
They considered the environmental Impact of suck products to be
minimal, and contended that such products should be exempt from
these data submission requirements because of the "Agency's obliga-
tion to take into account the differences in concept and usage
between various classes of pesticides."
The Agency recognizes the position of such conmenters, but
does not agree. Exclusion of the broad category "small-package,
low— toxic i-ty pesticide products" is too general and may preclude
the Agency from obtaining information necessary for an assessment
of environmental hazards resulting from pesticide products intended
for domestic-use applications. For some products, great quantities
(on an aggregate use basis) of small-package low-toxicity products
used in domestic-use applications can result in adverse environ-
mental effects, even though, a single application of such a product
would not cause any specific adverse effect beyond intended injury
to the target pests. The Agency recognizes that many smal 1- package ,
lowtoxicity, low-volume products do not pose an environmental hazard
even when viewed ,from an aggregate-use standpoint, and for these,
recommends that registration applicants consider submitting requests
for waivers of certain data requirements, in accordance with
§ 158.45 of 40 CFR § 158 [referred to at § 160-1 (g) of this subdivi-
sion ' '
However, it should be noted that a single set of acceptable
data for each chemical is all that is needed by the Agency. Thus,
it is unlikely that individual' small package producers will actually
be required to conduct such studies, since these studies will
ordinarily be conducted and resultant data furnished by a producer
of the active ingredient.
B. BENCHMARK CONCEPT.
One comment er expressed the view that the Agency should use1
benchmark techniques in hazard assessment, and that the data require-
ments of the guidelines should be drafted with this in mind. ' The
benchmark concept involves using presently available information
about chemicals for which data have been generated to predict the
behavior of chemicals whose behavior patterns are unknown. The
Agency recognizes the advantages of benchmark techniques as a
means of hazard assessment, and does not rule out their future
use. However, it does not believe that 'such techniques have been
developed to the point where the Agency can rely on such data to
predict environmental fate as a substitute for requiring actual
data about the chemical for which registration is sought.
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C. DEGRADATION STUDIES
1. Hydrolysis, Many commenters suggested revisions in proposed
§ 163.62-7(b), which set forth proposed requirements for hydrolysis
testing. The commenters believe that their proposed revisions to
the data requirements would reduce the time and expense involved in
performing hydrolysis testing but would still permit the Agency to
obtain the data necessary for hazard evaluation.
The proposed version of the guidelines required laboratory
hydrolysis studies at two concentrations, two temperatures, and
three pH values. Many commenters recommended that the Agency per-
mit hydrolysis testing to be conducted at one concentration and at
one temperature. Some of these commenters stated that additional
testing at different concentrations or temperatures would be
appropriate in :the event that initial testing results identified
hydrolysis as a major route of degradation of the pesticide.
The Agency agrees with the commenters that testing at one
temperature and concentration will yield satisfactory data for
hazard analysis. Therefore, the Agency has revised its provisions
regarding the test procedure for hydrolysis testing. The guide-
lines now require "one or more concentrations of the test substance"
to be tested, with an upper limit on the; permissible concentration
of 250 parts per million. The guidelines also permit testing at
one temperature, and provide that the temperature of the hydrolysis
reaction shall be maintained at 25 £ 1°C. However, the Agency has
retained the requirement that the study be run at pH 5, 7, and 9
because, in its judgment, the three pH-'s are necessary to span
normally-encountered environmental conditions*
2. Soil .Photodegradation. . Studies of the photodegradation.or -
photolysis of.a.pesticide on soil surfaces were required by proposed
§ 163»62-7(c)» Numerous commenters objected to the requirement and
suggested either deleting or modifying the.section. EPA has retained
the requirement but has adopted a number of suggestions for its
modification. See § 161-3 of this subdivision.
One commenter recommended restricting the requirement for soil
photolysis data to those products for which photodegradation is
likely to be a significant mechanism of decomposition. The proposed
guidelines required soil photolysis data to support the registration -
of any end—use product with a terrestrial non-crop use, a fruit/nut
tree (orchard) crop use, a fieldvegetable crop use, an aquatic use,
a forestry use,, or direct discharge aquatic•impact use.
The Agency agrees with the commenters that this data require-
ment in the proposed guidelines was overly broad and has added a
"When required" paragraph to § 161-3 of the current guidelines
which states :that soil photolysis data are required to support the
registration of only those end-use products with terrestrial crop
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uses or forestry uses. The section expressly excludes from the
data requirement products with uses which will not result in
pesticide residue on the soil surface, i.e., "uses involving
injection of the product into the soil or incorporation of the
product into the soil upon application ..."
Most of the comments focused on the test methodology. Some
commenters suggested deleting the requirement because of the
difficulty and cost of the study or because of the difficulty in
interpreting the data. Others argued for its deletion on the
grounds that con par able information could be obtained from a
"sensitized" water photolysis study. Finally, some commenters
proposed specific changes in the "test methodology* The change most
frequently suggested was that the study be performed on an inert
surface rather than on soil. ;.-
EPA recognizes that a soil photolysis study requires expensive
and sophisticated testing techniques. Nonetheless, the Agency
believes that it i£ appropriate to- require the study for products
which are likely to leave pesticide residues on the soil surface
since soil surface photolysis can be an important factor in the
degradation of many pesticides not incorporated into the soil. The
Agency has expanded the list of references to include more informa-
tion on the performance of these studies which should aid those
who find the study difficult to perform.
The;Agency has considered but does not agree with the sugges-
tion of one ccnunenter that aqueous photolysis studies using water
with and1 without p'hotosensitizers would provide the same informa-'
tirm that1 would be generated by a soil photolysis., study. A photo-
sensitiaer•is a substance which alters the rate or the path of
decomposition of a chemical. The commenter's suggestion is
apparently based on the assumption that the photodegradation
process on soil differs from that in water "only in that -photosen-.
sitizers: are present'in- the former. EPA agrees with the c'onmenter
that photolysis in water and soil may differ because of the presence
of photoj&ensitizers and that soil-is more likely to have such
con pounds. However, this is not the only way in which soil and
water may differ. • The Agency anticipates that the amounts and
kinds of photoproducts and second order degradation products may
differ for studies done in soil and water. For example, a photo-
product 'formed in water is likely to be hydrolyzed, but the same
photoproduct formed in soil could also react with soil organic
matter or be metabolized by soil microbes. Consequently, the Agency
rejects the suggestion to rely on aqueous photolysis studies.
A number of commenters critized the proposed soil photolysis
data requirement because of their belief that EPA would not be able
to interpret the data. In particular, EPA would be unable to dis-
tinguish between degradation resulting from exposure to sunlight
and degradation caused by chemical reactions with the water or
organic matter in the soil or by microbial populations in the soil.
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The Agency agrees that the study required by the proposed guidelines
would not have produced data that could enable it to distinguish
among these various degradation mechanisms. In order to do so, the
Agency has added a test standard requiring a "dark control/" i.e.,
a requirement-that'the study be performed both in light and in
darkness. [See § 161-3(c)(2)(v).] The differences obtained under
the two conditions will indicate to what extent decomposition is
attributable to photolysis.
Ccnuaenters also suggested that the results of a soil photolysis
study are of limited usefulness because the test is performed on
only one type of soil. Various types of soils will produce different
results due to differences in organic matter content, microbial
populations, and photosensitizers. EPA agrees that the differences
between soil types will significantly limit the Agency's ability to
make quantitative extrapolations of photolysis data from a test
soil to another soil type. The Agency, however, does not intend to
perform quantitative extrapolations based on these data; rather the
Agency's purpose is to obtain an understanding of the importance of
photolysis of soil surface pesticide residues and to identify major
metabolites formed by this mechanism. The Agency concludes that
the test is capable of generating data which satisfy this purpose,
and therefore has retained the . requirement. i • , .
Finally, EPA has considered the frequently-offered suggestion
to permit the use of an inert surface such as glass or Teflon
instead of soil in this study. Although these studies would be
somewhat less expensive, the data generated would not permit the
Agency to evaluate the • effects of degradation frqcn':the .combined •'.;-
factors associated with both sunlight and soil, ijinDce: natural and -
more cannon situation. ' Therefore, the Agency .has,:; .rejected the
proposed revision. '.•••.•' • • • .' ',- . ,.-,''
3. Air photolysis. Most of the public comments onproposed
§ 163.62-7(c) recommended deleting the requirement for air
photolysis studies. While the Agency has not accepted this
recommendation, the Agency has.revised the proposed provision to
provide that the data-will be required-only on a .• qase-by-case
basis and to establish standards for the performance of the test.
Several' comments noted that the results of an air photolysis study
are not needed for non-volatile compounds and compounds that do
not vaporize readily. Other conments suggested that the data are
needed only to evaluate possible hazards to workers reentering a
treated area. EPA agrees with-both canments and has added "When
required" paragraphs which provide, in § 161-4(b);
Data from a laboratory photo degradation study
in the vapor phase will be required by the
Agency on a case-by-case basis to support the
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registration of an end-use product with orchard
or field-vegetable crop uses that involve
potentially significant exposure to workers.
Data from such a study will also be required
to support the registration of a manufacturing-
use product which legally could be used to
make such an end-use product. The Agency
will make an assessment of what constitutes a
significant exposure to workers based on the
information required by § 163-2(b)(2).
and in § 163-2(b)(2)s
Data from a laboratory volatility study will be
required on a case-by-case basis by the Agency
to support the registration of each end-use
product intended for commercial greenhouse,
orchard, or field/vegetable crop uses that
involve signficant inhalation exposure to
workers. Such studies will also be required
to support the registration of each manufactur-
ing-use product which legally could be used to
make any end-use product for which laboratory
volatility data are required.
(2) The Agency will evaluate the follow-
ing information provided by the registration
applicant to make an assessment of what con-
stitutes a significant inhalation exposure to
workers; . .
(i) , Vapor pressure at 25°C and water
solubility of the pesticide active ingredient
(§§ 64-9 and 64-8 of Subdivision D);
(ii) Soil adsorption coefficient (K
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(vli) Inhalation toxicity of the pesticide (§§ 81-3
and 82-4 of subdivision F).
In accordance with these paragraphs, the Agency will consider
both the volatility of the pesticide and the possibility of worker
exposure in determining which products will be required to provide
air photolysis data. •
Other comments stated that requirement for air photolysis data
should be deleted because the study is costly and complicated and
the results are difficult to interpret. The Agency acknowledges
that the test procedures are expensive and difficult to perform and
that data are rarely easy to analyze. Nonetheless, the test
procedures are reliable, and useful data have been generated from
such studies* [See the references in § 161-4(e).] Therefore, when
these data are needed to evaluate potentially hazardous exposures,
the Agency will require the data.
D. METABOLISM STUDIES
1. Aerobic Soil Metabolism Studies. While most ccnunenters recognized
the Agency's need for data from an aerobic soil metabolism study,
they had many ceminents on how such a study should be performed.
[See proposed § 163.62-8(b).] The three data requirements in this
study %ftiich received the most comment were:
- The requirement to use three different types of" soil;
- The requirement to continue the study until "ninety percent
loss of the pesticide occurs"? and
- The requirement to identify every residue which constitutes
more than ten percent of the initial application or 0.01 ppm,
whichever is greater.
After reviewing the comments on the requirement to perform the
aerobic soil metabolism study on three different soil types, the
Agency agrees with the reasons advanced in support of reducing the
requirement to one soil type. A number of ccmmenters stated that
the variation in results from soil to soil was conparatively small
and that there were rarely qualitative differences in the degrada-
tion products formed in different types of soil. Thus, the kind
of soil seemed to influence only the rate of degradation. They
stated, moreover, that rate calculations determined in a laboratory
test such as the aerobic soil metabolism study are not highly
reliable for predicting degradation rates under field conditions.
Accordingly, they concluded that the results of an aerobic soil
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metabolism study performed on more than one type of soil would be
only marginally useful for the Agency. Many ccnuaenters also
pointed out that by reducing the number of soil types required
from three to one, the Agency could lower the cost of the study.
The Agency has been persuaded by these reasons, and has reduced
the requirement to only one soil type. See § 162-1 (e)(2)(i) of
the current guidelines.
The Agency has also revised the requirements concerning the
duration of an aerobic soil metabolism study. The proposed guide-
lines stated that if the data were used to support the registration
of a product with a forestry use, a terrestrial crop use, or a
terrestrial non-crop use, the stddy should last one year or until
90 percent of the active ingredient had degraded and the pattern of
formation and decline of metabolites had been established, whichever
was shorter. Several ceminenters stated that the 90 percent loss
criterion was inappropriate.
The Agency agrees with the comments. In some cases it will be
possible to establish degradation rates for the active ingredient
and rates of formation and decline of the degradation products
before the active ingredient has degraded 90 percent. In other
cases, the active ingredients may degrade very rapidly, so that
there will not have been enough time to evaluate the pattern of
formation and decline of degradation products by the time that 90
percent of the active ingredient has degraded. In short, the 90
percent degradation figure often may not be relevant to the evalua-
tion of patterns of formation and decline of degradates, one of
the Agency's primary concerns in determining the duration of an
aerobic soil metabolism study. In order to reflect this reasoning,
the Agency has prepared f 162-1 (c) (2)-(viii) to read:
Data must be collected until patterns
of decline of the parent compound and
patterns of formation and decline of
degradation products are established in
soil, or for one year, whichever comes
• first . . .
Finally, the Agency has modified the provisions concerning
the level of sensitivity required for the analytical methods used
to identify the residues of degradation products remaining in
soil. The proposal, § 163.62-8(b), required the identification of
residues which constitute ten percent of the initial application
level or 0.01 ppm, whichever was greater, and further provided
that the experimental dose rate must approximate the field appli-
cation rate. Public comments identified two problems with this
requirement* First, the ten percent criterion was too broad for
pesticides applied at high rates (e.g., greater than 5 ppm). If a
pesticide is normally applied at 20 ppm (as is the case for some
soil fumigants), an applicant would, for example, only have to
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identify residues in excess of 2 ppm, 200 times higher than the
requirement imposed for other pesticides. Thus, a ten percent
criterion would not only deny the Agency access to residue data
necessary to make a hazard assessment, but could also indirectly
encourage the use of higher application rates. Second, detection
of residues which constituted only 0.01 ppm might be difficult.
As a result of the many comments received on this issue, the
Agency has revised the criteria for identification of soil residues.
The criterion based on 10% of the original application level has
been deleted, and the requirement for identification of residues at
the 0.01 ppm level is to be taken as a suggested goal to be met or
surpassed. See § 162-l(c)(2)(vi). The Agency believes that O.Ol
ppm is a valid target level in light of the data received from
many registrants and the current literature where this level is
either met or surpassed. It is recognized, however, that this
level of analysis cannot be achieved for all pesticide chemicals
and their degradation products. Therefore, registration applicants
will not be penalized for not being able to meet the 0.01 ppm goal
due to limitations of the analytical method.
2. Studies of microbial effects. In the 1978 proposed guidelines,
the Agency proposed the following sets of data requirements pertain-
ing to microbial effects in relation to pesticides:
§ 163»62-8(f)(2) Effects of microbes on pesticides;
§ 163,62-8{f){3) Effects of pesticides on microbes? and
§ 163»62-8{g) Activated sludge metabolism.
Subsequent to the proposal, public comments, Agency internal dis-
cussion* and the recommendation of the FIFRA Scientific Advisory
Panel all focused on the need for the Agency to obtain more defini-
tive information on test procedures and better assessment of the
value of test results before promulgating final rules on this
subject. The Agency agrees with these arguments, and has not
included these data requirements in Subdivision N.
This decision should not be interpreted to suggest that the
Agency is no longer interested in microbial effects, nor that their
importance in environmental fate of pesticides is not important.
It merely reflects agreement among scientists both within and
outside the Agency that until useful conclusions can be drawn from
properly designed studies, no studies should be required. In this
regard, the Agency invites submittal of more suitable and useful
test protocols and examples of test results and evaluations that
support the protocols.
The microbial effects studies provided in the 1978 guidelines,
and the microbial studies in the Subpart; J proposal (45 FR 72948)
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do not encompass the full scope of microbial effects studies that
should be examined if a serious examination of environmental effects
involving microorganisms is to be undertaken. When suitable studies
can be designed to produce useful, cogent data regarding microbial
effects, the Agency is likely to include all such studies within
& single, separate subdivision.
HSTICIBE RESH30E MOBIU^TT STODIES
1. Soil column leaching studies. Proposed § 163.62-9(b) established
data requirements intended to provide the Agency with information
about the propensity of a pesticide to leach through soil. The
leaching study required was a soil column laboratory study using
a minimum of four soils, one of which must be used to study leaching
of pesticide residues after the pesticide had been aged in soil
under aerobic conditions.
A number of ccmmenters recommended deletion of the requirement
for column leaching studies. The consensus of the ccmmenters was
that such studies are wasteful of time and resources, because the
Agency can obtain sufficient information about the leaching proper-
ties of a pesticide from data obtained from adsorption/desorption
studies. One commenter gave as an additional reason for deleting
the requirement that the Agency had itself recognized a number of
problems associated with soil column leaching studies. Another
commenter took the opposite view, and recommended that .adsorption/
desorption- .data requirements .be deleted a'nd the soil column'
laboratory study requirements be retained*
In response to public comments, the Agency has combined its
data requirements pertaining to adsorption/desorption and leaching.
The guidelines now provide that a laboratory study is required to
provide a quantitative estimate of mobility in soil* but that? with
some limitations, the investigator may select which technique to
use. A brief discussion of the three techniques follows. Thin-
layer chromatography is one laboratory technique which permits the
investigator to determine the movement of pesticides in soil coated
on glass. A soil column study is another laboratory procedure
which provides data on the movement of pesticides in soil. How-
ever, the soil used for the study is placed in a vertical column
(cylinder), and movement of the pesticide from the top to the
bottom is measured. A batch equilibrium study, on the other hand,
involves the collection of data on the partitioning of a. pesticide
between soil and water; in this study, the pesticide is first
added to water which is thereafter mixed with soil. The Agency
believes that it can give applicants the choice of which techniques
to use to measure leach ability and still obtain adequate data for
the assessment of pesticide mobility.
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Therefore, the guidelines now permit data relating to products
intended for terrestrial and forest uses to be obtained using soil
thin-layer chroma.tography, a soil column study, or a batch equilibrum
{adsorption/destfrption) study. A batch equilibrium study must be
performed^ however, for pesticides intended for aquatic or aquatic
impact uses.
2. Sffects of Pesticides on Groundwater. Several ccmmenters
recommended that the guidelines take into account the potential
effects of pesticides on ground water. The Agency agrees and
believes that the requirements of Subdivision N will provide the
Agency with data that will enable it to ascertain and assess
possible ground water contamination by pesticides.
Ground water includes both the aquifers which store water
below the earth's surface and other subsurface water sources. It
is a valuable resource which has been increasingly used both as a
primary and supplementary source of water in many regions through-
out the United States. However, since it is a hidden resource,
its proper management has often been difficult to achieve. The
pollution of ground water is difficult to detect because it usually
takes place very slowly. Moreover,1 once the water is contaminated,
the loss of usefulness of the water and the effort £0 restore the
water to a useful state may extend over a long period of tine.
, The Agency considers 'that it is probably more -cost efficient
to prevent the contamination of ground water than to remove pollu-
tants from it. Therefore, as part -of the assessment of environ-
mental fate, of a pesticide1, the Agency will' evaluate.'.its '.potential;:~-"
for ground Water contamination. The "char act eristics of the .-pesti—• '*••
cide that are most pertinent to this -inq'uiry are'::'".!, '" . •• •-. . ':r-'
- Leachability;', . • :' ' ••-.• . •'•••' • .
- Adsorption/desorption characteristicsj
- Resistance td chemical, 'photochemical, and biological
degradation;
- Solubility in water; and
- Volatility.
The tests described in Subdivision N provide the Agency with data
from which it can assess these characteristics of a pesticide.
It should be noted that, while the data requirements for
leaching studies have now been modified, this change is not con-
sidered likely to reduce the Agency's ability to assess the risk
that a pesticide will contaminate ground water. In the 1978 pro-
posed guidelines, the Agency required that an applicant conduct
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both soil thin-layer chromatography teStiiig and a soil .column
leaching study to measure leachability. As a result of public
comment, however, the Agency has been convinced that it can obtain
satisfactory data from either of these studies, or from an adsorp-
tion/ desorption study. Therefore, the guidelines now provide that
an applicant submit data from any one of these three studies.
DISSIPATION STUDIES: COMBINATION PRODUCTS AND TANK MIXES
A few commenters recommended deleting proposed § 163.62(10(f),
which prescribes data requirements for pesticides applied in a
combination or tank mix. The conmenters questioned whether the
Agency has evidence of any adverse effects associated with such
combinations, or evidence that a pesticide will behave differently
when added to soil at the same time as another pesticide than if it
had been applied alone. The Agency has data that indicate that the
persistence of a pesticide in soil may increase as a result of its
application with another pesticide serially or in a mixture. Based
on such information, the Agency believes that the data required by
proposed § 163.62-10(f) is useful in hazard evaluation and has
retained the data requirement, but only on a case-by-case basis.
Refer to PR Notice 82-1, entitled "Revised Policy on Label Claims
for Tank Mixing" (January 12, 1982) for a further discussion.
At the suggestion of several conmenters, the Agency has amended
the provision to require incorporation of the test substance in
soil only for those use patterns that require soil incorporation as
recommended by label instructions.
G. ACCUMULATION STUDIES
1. Rotational crop studies. Ccmmenters have suggested a number of
revisions in proposed § 163.62-11(b), which establishes data
requirements for studies of pesticide accumulation in rotational
crops. The Agency has substantially revised the requirements for
these studies, now in §§ 165-1 and -2, to take their comments into
account. The main suggestions and Agency responses are as follows:
(a) Several ccmmenters objected to the requirement for a
laboratory or greenhouse study and proposed an amendment to permit
a small plot outdoor study. The ccmmenters stated that an outdoor
study would more closely approximate growing conditions than would
a laboratory study. The Agency has now revised the requirements in
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response to these comments to permit -the applicant: to furnish data
from a "confined" (as contrasted to "field") study which can be a
laboratory, greenhouse, or outdoor small-plot study.
(b) Several contnenters recommended that the guidelines estab-
lish a trigger that would determine when field studies would be
required. The suggested trigger level of 0*1 ppm of unincorporated
extractable residue was proposed by two commenters. A third com-
menter proposed that a field study should not be required unless
there is a single extractable component greater than 0.02 ppm,
expressed as parent pesticide ccmpound, present in the raw agricul-
tural commodity. The guidelines, at § 165-2(b)(1) now provide
that a field study is required "when significant C1^ pesticide
residues of concern to the Agency are detected in the crops analyzed
in the confined accumulation study, § 165-1." Significant residues
are defined in§165-1{d) {1) as "parent compound, closely-related
degradates, metabolites and/or their conjugates in the crop, but
shall exclude C14 activity in the crop associated with that being
incorporated into the carbon pool and ultimately into natural plant
constituents." : ' • . • ' • ; • " . L'-'"' • • ' •' •• • • •
(c) Several commenters suggested that the Agency establish
tolerances for residues in rotational crops. The Agency now has
a procedure for establishing such tolerances* On January 13, 1981,
the Agency issued a policy statement entitled "Tolerance for
Pesticides Residues in Rotational and Follow-Op Crops, Meat, Milk,
Poultry and Eggs, and for Other Indirect or Inadvertent Residues."
Federal Register, Vol. 46 No. 8, p. 3016, Jan. 13, 1981. In that
statement1, the Agency announced that it will .follow' the general "
policy of-responding to requests by setting toler-ances for pesticides
residues resulting from crop rotation or crop replacement practices.
2. Fish accumulation studies. The Agency received numerous comments
concerning the proposed data requirements for fish accumulation
studies. These commenters addressed four main concerns:
- Commenters proposed that the Agency establish a tier approach "
to data requirements pertaining to pesticide accumulation in
fish. ' ' ''• . • ' ' -•' ' '
— Ccmmenters questioned the .need for and procedures specified
for the static (catfish) accumulation test.
- Commenters expressed concern whether the fish accumulation
data requirements in the environmental fate subpart are
redundant of or compatible with the fish accumulation data
requirements of proposed § 163.72-6 in Subpart E {now § 72-6
of Subdivision E).
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- Comraenters recommended changes in prescribed test procedures
for performing the studies.
The Agency has responded favorably to many of the proposed
revisions of this section, and as a result, the fish accumulation
test requirements have changed considerably from those previously
proposed.
Several commenters proposed that the requirement for a flow-
through study should be contingent on whether the parent and/or
significant environmental degradation product has octanol/water
partition coefficients greater than 1000 and half-lives in water
greater than 4 days. The Agency agrees generally with these commen-
ters that a flow-through study need not be performed in every
instance, and that there is a high correlation between octanol/water
partition coefficient and pesticide accumulation in fish. Never-
theless, the Agency does not believe that testing procedures have
been developed that would permit the Agency to use data on octanoV
water partition coefficient on a routine basis to determine whether
further testing is required. Therefore, the guidelines now provide
that the flow-through test requirement may be waived if the appli-
cant can provide evidence that the probability for accumulation is
low, based on the physical properties of the pesticide and any
other characteristics that bear on its environmental fate. In
this way, the Agency has retained the flexibility to require the
study for products for which the physical property correlations
have been established or for which the use patterns, application
rates or environmental fate and transport increase the possibility
for accumulation. . -.
A number of comments were received questioning:the need for
the proposed static "catfish" accumulation study. Ccramenters
expressed concern -that no established standard procedures exist for
performing the study; that there is a likelihood that the test fish
will suffer'adverse health effects? that the conditions for the
study bear little resemblance to actual environmental conditionsi
and that several chemical factors.decrease the value of the test in
assessing accumulation potential. The Agency has carefully studied
these comments and has concluded that the major benefit that the
study offers, the ability to judge the accumulation potential of
pesticide degradation products, is outweighed by the collective
shortcomings of the study as currently proposed. More Importantly,
though, some of these kinds of studies have neither been validated
nor verified, and suitable design criteria related to standardization
of the techniques are yet to be developed. The Agency has decided,
therefore, to delete the static test from the guidelines. The
Agency encourages further research in this area, with hope that
suitable low-
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Ccmmenters also suggested changes in test procedures for fish
accumulation studies, many of which have been incorporated into -the
guidelines. Host significantly, the Agency now requires identifi-
cation of chemical residues only from the two samples with the
highest residue levels. Residues below a specified level need not
be identified. "•o%'- '- 'r • v - - •' . ~" • ; - ""...'• '. '
Lastly, conmenters expressed concern about the relationship
between proposed Subparts D and E, both of which required data on
accumulation of pesticides in fish.
Subdivision N now requires the following laboratory and field
accumulation studies on fish:
(a) Section 165-4 provides that a laboratory flow-through expo-
sure study is required to support the registration of end-use
products intended for outdoor uses (except domestic outdoor
and greenhouse uses), enduse products intended for aquatic
impact uses resulting in direct discharges into the environ-
ment, and manufacturing-use products that could legally be
used to make such end-use products. However, such data
will not normally be required where the applicant can pro-
vide evidence that the pesticide and/or its principal
degradates will not reach water, will not persist in water,
or are unlikely to accumulate in fish.
(b) Section 165-5 provides for a field accumulation study to
measure pesticide residues in edible portions of fish under
more limited- circumstances: if'the end-use product is
.intended .for forestry use, aquatic non-crop use, or aquatic
impact use that results in direct discharge; if a laboratory
accumulation test shows evidence of accumulation, and if no
tolerance or action level for fish has been granted.
Subdivision E provides for both laboratory and field accumula-
tion studies (§§ 72-6 and 72-7, respectively), both on a case-by-
case basis.. " . • • .
Although Subdivisions E and N both contain data requirements
pertaining to the accumulation of pesticides, the Agency believes
that it is necessary to retain the requirements in both subdivi-
sions. First, the data requirements in-the two subdivisions serve
different purposes. Subdivision N contains data requirements
designed to obtain information about the hazard from accumulation
of pesticides in fish used as edible food sources for humans, and
incidentally, other animals that feed on fish or fish products.
Subdivision E, on the other hand, contains data requirements
intended to provide information on adverse effects of pesticides
on fish as nontarget organisms in the environment.
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Second, the applicant will not be required to perform dupli-
cate tests to furnish redundant data to satisfy the requirements
of both subdivisions. Where one study will satisfy the require-"
ments of both subdivisions, data furnished in response to the
requirements of one subdivision may be crossreferenced in the
registrant's submission under the other.
The Agency emphasizes that the Subdivision E guidelines require
accumulation testing on fish only on a case-by—case basis, with the
decision whether to test and what procedure to follow being made
after consultation between the registrant and the Agency. Laboratory
accumulation testing under § 72-6 of Subdivision E will be required
if the active ingredient or its principal degradation products are
"likely to persist in the aquatic environment, or if they accumulate
in the organs and tissues of mammals or avian species* Simulated
or actual field testing under § 72-7 will be required if there is
evidence that the pesticide is likely to cause adverse effects on
fish.' .- • • . •. : •
3. Microecosystems studies« The issue was raised that micro-
ecosystem testing is not required in the environmental fate guide-
lines for accumulation studies. The model ecosystem approach,
once perfected, could give valuable data as to pesticide mobility,
transport, toxicity, distribution, aceumulatI6n~7 and fate, it may
be useful, therefore, for the study of current problem areas and
pesticides that are currently registered for use. But more impor-
tantly, it may eventually be very helpful in providing useful data
in future registrations of certain new pesticides as the state of
the science of this technique improves•• .', '.•..'".
Scientists'are aware, however, that microecosysterns :are very
complex, and dafea generated by these systems on transformation,
transport, and accumulation of pesticide residues are often diffi-
cult to interpret. To be useful, several different systems would
have to be used. This could result in substantial cost to prospec-
tive registrants. More importantly, though, most such systems have
neither been validated nor verified, and suitable design criteria
related to standardization of the techniques are yet to be developed.
The Agency encourages further research in this area, with the hope
that suitable low-cost reproducible systems that yield the needed
information can be developed.
H. SUCTIONS OP 1978 PROPOSAL TO BE ISSUED AS SEPARATE SUBDIVISIONS
1* Reentry. A commenter suggested that the Agency should not defer
the issuance of re-entry guidelines but should impose data require-
ments relating to re-entry at the same time that these and other
data requirements are imposed. The commenter expressed concern
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28
that an applicant or registrant rai^it be burdened with duplicative
testing requirements if these studies could not be conducted simul-
taneously. The conmenter suggested that reentry data include a
determination of hazards due to chronic effects, allergic reactions,
and diminished health.
Guidelines have been written by the Agency to establish data
requirements to support the establishment of re-entry intervals for
pesticides. These requirements are in Subdivision K "Pesticide
Assessment Guidelines: Re-entry Protection.*
2* Disposal. Die 1978 proposal asked for suggestions as to what
data should be required relating to pesticide disposal. In response
to that request, one commenter suggested that the Agency could
require data on incineration parameters and chemical degradation.
All comments received in connection with the proposal will be
addressed in the development of Subdivision P, "Data to Support
Disposal Instructions." This subdivision will take into account
the disposal statements in Subdivision H, "Labeling Guidelines
for Pesticides and Devices," the proposed guidelines on disposal
developed under the Resource Conservation and Recovery Act, and
the fact that disposal of pesticide containers must be addressed
as well as pesticides. ' •'' • , " ..
3. Pesticide ResidueDatafor Tolerances and Tobacco. Sections
in proposed Subpart D dealing with tolerance clearance and with
pesticides in tobacco, §§163.63-1 and 163.64-1, respectively,
will be addressed in a separate subpart entitled Subdivision O,
"Pesticide. Assessment .Guidelines i ••' Residue' Chemistry. ".• . .•
APPENDIX TO 1978 PROPOSAL
Several ccmmenters pointed cut that the Appendix to the 1978
proposed guidelines stated that acceptable test procedures were not
available for Items No. 10 (Volatility)/'12 (Water Dispersal), 13
(Field Dissipation), 14 (Aquatic Food Crop), 15 (Aquatic NonCrop),
17 (Combination and Tank Mixes), 18 (Long Term Study), and 19
(Accumulation). They consequently recommended that the comparable
guidelines sections include only testing for which established
protocols are available. Other ccmmenters have indicated to the
Agency that many Appendix references were either inaccurate, irrele-
vant to the subject matter addressed, or out of date and not reflec-
tive of the current state of the art in environmental fate studies.
In response to these concerns, the Agency has thoroughly
reviewed the references. Those which were judged to be no longer
useful for their intended purpose were deleted and replaced by
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29
references to suitable information. In an attempt to make the
references more instructive and useful, the Agency has included
explanations as to extent of usefulness of each reference.
All references are now located at the ends of the appropriate
sections to which they properly correspond, rather than in a single
large appendix section.
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30
SUBDIVISION N - CHEMISTRY REQUIREMENTS: ENVIRONMENTAL FATE
Series 160: GENERAL INFORMATION AND REQUIREMENTS
§ 160-1 General information.
(a) Purpose and scope. Pesticides interact with the environ-
ment with possible adverse consequences for man and other nontarget
species. The purpose of this subdivision is to describe in more
detail the Agency's requirements for data concerning the environ-
mental fate of pesticides, which are set forth at 40 CFR § 158.130.
These data must be submitted to support the registration of most
manufacturing-use products. The Agency will use these data in
the identification and assessment of the potential hazards asso-
ciated with each of the anticipated uses of a pesticide in the
different environments in which they are used.
(b) Application of requirements. (1) Application status and
compliance. The requirements imposed by 40 CFR § 158.130 and
described in this subdivision apply to products already registered
as well as those being proposed for registration. The Agency will
notify registrants of products already registered, either (occa-
sionally) through the data call-in program, or (routinely) upon
development of a registration standard, as to when they must
satisfy the data requirements of this subdivision* Refer to
§ 158.30 of 40 CFR §158 for details of application status and sub-
mittal times.
(2)' "When required" and "Test substance" requirements. The
registration applicant should be careful to distinguish between the
"When required" and the "Test substance" paragraph requirements of
each section of this subdivision;
(i) The ""When required" paragraphs pertain to the circum-
stances under which data shall be required, and specify the cate-
gories of products for which data must be generated to support
registration applications. The test data are ordinarily required
to support the registration of each end-use product with the pre-
scribed use pattern and each manufacturing-use product used to make
such an end-use product.
(ii) The "Test substance" paragraphs relate to the test
procedure required to produce acceptable data, and state whether
the test substance for a particular study may be the technical
chemical, a typical end-use product, or a radioactively-labeled
analytical grade chemical. ,
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31
(3) Testing to meet requirements. Since studies de-
scribed in this subdivision would ordinarily be conducted by
the basic manufacturer, pesticide formulators would not often
be expected to conduct such tests themselves to develop data to
support the registration of their individual products, They
may do so if they wish, but they may also rely on the basic
pesticide manufacturer's data already developed. See §158.50
of 40 CFR § 158 for details of the data submittal exemption
for pesticide formulators.
(c) Approach of subpart. (1) This subdivision describes
the Agency's requirements for data pertaining to environmental
fate of pesticide chemicals* The data requirements are divided
into five categories of tests (degradation, metabolism, mobility,
field dissipation, and accumulation).
(2) The need for data pertaining to some or all of these
tests depends primarily on the pesticidal use pattern. For
purposes of this subdivision, pesticides which are used oudoors
are categorized by one or more of the following use patterns:
terrestrial, aquatic, forestry, and aquatic impact. Applicants
should consult the use pattern index (Appendix A of 40 CPE § 158}
to determine which use pattern category includes their specific
use patterns.''
(d) Summary tables. (1) Tables 1 and 2 summarize many of
the data requirements set forth in 40 CFR Part 158 and described in
this subdivision. Table 1 lists data requirements for terrestrial
and forestry use patterns, and Table 2 lists data requirements for
aquatic and aquatic impact use patterns* 'Terms used in these
tables have been defined in f 160-2 and described in more detail
with examples in § 160-3.
(2) The data requirements for long-term soil dissipation
studies are not included in the tables. Also, the following
specialized use patterns are not included in the tables: special-
ized aquatic uses (e.g., antifouling paints on ships and related
protective or preservative uses), field volatility, and combination
and tank mixes. These uses are covered in the text under the appro-
priate specific data requirements.
(3) As an aid to identification of testing requirements which
may support more than one use pattern. Tables 1 and 2 are presented
in a modified bar graph format. Any two or more identified use
patterns which are connected by a line on the table have identical
environmental fate testing requirements and therefore the data
derived from any one test will satisfy the data requirements for
all designated use patterns. Where a line does not connect use
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32
patterns on the table, the stringency of the testing retirements
differs sufficiently among the identified use patterns so that the
data derived from any one test will not satisfy the data require-
ments for all other designated use patterns. In the case of soil ,
field dissipation data requirements for terrestrial and forest use
patterns, however, some degree of substitution of data requirements
among identified use patterns is possible. For example, data derived
from studies for use patterns (e.g., orchard crop) conducted under
more rigorous testing requirements may substitute for or be used
to satisfy the data requirements for use patterns (e.g., terres-
trial non-crop) that require less rigorous testing requirements,
but the reverse is not permissible.
(e) Organization and content of sections» (1) Section 160-2
contains definitions applicable to this subdivision.
(2) Section 160-3 describes the use patterns of pesticides
which form the basis for the requirements of this subdivision.
(3) Section 160-4 describes general standards for tests to
be performed pursuant to this subdivision.
(4) Section 160-5 contains general requirements for the
reporting and evaluation of data.
(5) Section series 161 through 165 provide the specific test
standards and reporting requirements for each major data requirement
category: "•';•.
(i) Section series 161 deals with degradation studies;
' (ii) Section series 162 deals with metabolism studies;
(lii) Section series 163 deals with mobility studies;
(iv) Section series 164 deals with dissipation studies; and
(v) Section series 165 deals with accumulation studies.
(f) . References»' (i) At the end of each section are
referenced examples of published literature containing acceptable
procedures and supplemental background or ancillary material which
may be consulted in developing test protocols. To aid the regis-
tration applicant in finding appropriate information within the
list of publications, the Agency has added a brief annotation
following each reference* The annotations point out the usefulness
of each publication for development of protocols.
(ii) The Agency recognizes that more than one referenced
study may be used in developing a protocol in a given area. In all
cases, if the referenced procedure(s) used to develop an alternate
protocol contain(s) other information that is inconsistent with
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33
Table I.
Summary of Environmental Fate Data Requirements for
Terrestrial and Forestry Use Patterns.
Terrestrial Uses
Field
and
Domestic Green- Non- Orchard Veg.
Data Requirements* Outdoor House Crop Crop Crop
Degradation
Hydrolysis
Photodegradation
—water
-soil
Metabolism
Aerobic Soil
anaerobic Soil**
Anaerobic Aquatic
Mobility
Leaching***
Field Dissipation
Soil****
Water
Forest
Accumulation
Rotational Crop
Irrigated-Crop
Fish
Aquatic Nontarget
==x
x=
Fores-
try.
Test
Identical
for Aquatic
S Aquatic
Impact Use
Patterns
Yes
Yes
No
No
No
No
=X
X
Yes
Yes
Yes
**
****
Data requirements cited in § 161—4 (Photodegradation studies in air)»
§ 163-2 (Laboratory volatility studies), § 163-3 (Field volatility
studies), § 164-4 (Dissipation studies for combination products and
tank mix uses), and § 164-5 (Long—term soil dissipation studies) are
not included in this table.
The anaerobic aquatic metabolism data may be substituted for the
anaerobic soil metabolism data but the reverse is not permissible.
For domestic outdoor and greenhouse uses a batch equilibrium (adsorp-
tion/desorption) study must be conducted.
Data derived from studies for use patterns (e.g., field and vegetable
crop) conducted under more rigorous testing requirements may substitute
for or be used to satisfy the data requirements for use patterns (e.g.,
orchard crop) that require less rigorous testing requirements, but the
reverse is not permissible.
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• I • . 34
Table 2. Summary of Environmental Fate Data Requirements for Aquatic
and Aquatic Impact Use Patterns.
Aquatic .'Uses ; Aquatic Impact Uses
Test Identical
: for Terrestrial
Direct Indirect and Forestry
Data Requirements* Food Crop Non-Crop Discharge Discharge Use Patterns
Degradation
Hydrolysis
PhotOdegradation
-water
-soil' ' '
Metabolism
Aerobic Aquatic
Anaerobic Aquatic**
Mobility
Leaching***
Field Dissipation
Soil (sediment)
Water '
Forest •
Accumulation
Rotational Crop
Irrigated Crop
Fish
. Aquatic' Nontarget
X X
X X=
X
x»maMmsBBB»aBK«mx
x=
Yes
Yes
No
No
No
=X
Yes
Yes
'Yes
Data requirements cited in § 161-4 (Photodegradation studies in air),
§163-2 {Laboratory volatility studies), § 163-3 (Field volatility
studies), § 164-4 (Dissipation studies for combination products and
tank' mix uses) , and § 164-5 (Long-term soil dissipation studies) are
not included in this table.
The anaerobic aquatic metabolism data may be substituted-' for the
anaerobic soil metabolism data; but the reverse is not permissible.
Mobility studies for aquatic and aquatic impact uses are not
applicable for leaching, but are for interpretation of surface
runoff mobility and dispersion in an'aquatic habitat. Therefore,
a batch equilibrium (adsorption/desorption) study must be conducted.
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35 -•: .
test standards and requirements as specified in the guidelines,
then the alternate protocol must be modified to conform with the
test requirements in the guidelines.
(iii) In 40 F8 26802 (June 25, 1975, pages 26878-26896), the
Agency provided a detailed discussion of many of the tests described
in §§ 161-1 through 165-4. This information may be of help to the
registrant.
(g) Waivers. Refer to 158.50 of 40 CFR § 158 for details on
the policy for waiver of data requirements.
§ 160-2 Definitions.
(a) Terms used in this subdivision shall have the meanings
set forth in FIFRA in f 162.3 of the FIFRA Sec. 3 regulations, and
in § 60-2 of Subdivision D.
(b) In addition, for the purposes of this subdivision:
(1) The term "agricultural use" means the use of a pesticide
product in the production of animals and plants for food, feed,
fiber, lumber, flowers, ornamental value, pets, condiments, bever-
ages, chemicals, fuels, smoking and chewing products, and related
commodities and purposes.
(2) The terra, "aquatic crop" means a planting of "vegetation
and the produce thereof for which all or part of'the life cycle
involves immersion or suspension of above-ground plant parts in
water. * • '
(3) The term "aquatic food crop use" means the use of a
pesticide product at any aquatic site for the purpose of controlling
pests or providing protection from pests in any aquatic crop grown
for the production of human food or .domestic animal feed, or for
plant regulating purposes in such crops.
(4) The term "aquatic impact use" means use of a pesticide
product on water in an enclosed facility or aquatic site that is
not accessible to- wildlife, birds, fish, or aquatic organisms but
from which treated water may subsequently be discharged into natural
or outdoor bodies of water accessible to wildlife, birds, fish, or
other aquatic organisms.
(5) The term "aquatic noncrop use" means the use of a pesticide
product for the purpose of controlling pests or providing protection
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36
from pests in or adjacent to any aquatic site other than that used
for production of human food or domestic animal feed, or for plant
regulating purposes on such plants*
(6) The term "aquatic use" means use of a pesticide in or
adjacent to any outdoor aquatic'.site readily accessible to wildlife
or to aquatic and semiaquatic animals and plants.
(7) The term "direct discharge" of a pesticide means the
release, treatment, or' application of a pesticide product directly
to water at sites within or directly connected to bodies of water
to which wild animals, birds, fish, and similar, organisms have free
access* " '
(8) The term "domestic outdoor use" means the domestic (non-
commercial) application of a pesticide product around (but not in)
the home*
(9) The term "field and vegetable crop use* means use of «
pesticide product for the purposes of controlling pests or providing
protection from pests in any field crop and/or vegetable crop, or
for plant regulating purposes in such crops.
(10) The term "forestry use" means use of a pesticide product
for the purpose of controlling pests or providing protection from
pests in forests, forest tree''nurseries, or reforestation sites, or
for plant regulating purposes on plants at such sites.
(11) The term "greenhouse use" means use of a pesticide
product for the purpose of controlling pests or providing protection
'from pests in crops grown in commercial greenhouses, or for plant
regulating purposes on such plants.
(12) The term "indirect discharge" of a pesticide means'
release, treatment, or'application of a pesticide product'.to water
at sites not directly connected to bodies of water to which wild
animals, birds, fish, and similar organisms have free access.
(13) The term "material balance" means an accounting of the
quantities of a chemical and its degradates in a defined system
based on total radioactivity and/or other recognized analytical
methodology.
(14) The term "nonagricultural use" means the use of a
pesticide product for all purposes other than those included under
the term "agricultural uses."
(15) The term "orchard crop use" means use of a pesticide
product for the purpose of controlling pests or providing protection
front pests in trees, vines, and shrubs grown or maintained for
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37
production of fruits and nuts, ox^'Edr of the FIFRA sec. 3
regulations* For the purposes of this subdivision, uses of pesticides
in greenhouses, for pulp and paper mill water treatments, and for
industrial cooling water treatments are considered outdoor uses.
(17) The term "plant regulatory purposes" means those purposes
indicated in sec. 162.3 (ff)(14) of the FIFRA sec. 3 regulations.
(18) The term "serial application" refers to the label-
recominended use of a pesticide on a site before or after application
of another pesticide to that site, such that the presence of one of
the pesticides may affect (usually enhance or complement) the
effectiveness and usefulness of the other.
(19) The term "tank mix" refers to the mixture of two or more
different pesticide products in a spray tank or other application
equipment for the purpose of subsequent application of all products
simultaneously.
(20) The term "terrestrial crop" means a planting of vegetation
and the produce thereof for which the entire life cycle of the
plants involves germination, growth, and 'maturation in association
with anchorage in soil above the water table.
(21) The term "terrestrial noncrop use" means -the use of '
a pesticide product for the purpose of controlling pests or provid-
ing protection from pests in any terrestrial vegetation other than
that used for production of human food or domestic animal feed-,
or for plant regulatory purposes on such plants.
(22) The term "terrestrial use" means use of a pesticide in
greenhouses or in any or all outdoor land sites except forests and
forestry use sites.
(23) The tern "typical end-use product" means a pesticide
product that is representative of a major formulation category
(e.g., emulsifiable concentrate, granular product, wettable powder)
and contains the active ingredient of the registration applicant1s
product.
§ 160-3. Use Patterns.
(•a) General. Environmental fate data are required for pesti-
cides intended for outdoor uses. Outdoor-uses include most agricul-
tural uses of pesticides and many non-agricultural uses, mostly in
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38
the terrestrial and aquatic non-crop categories. To help specify
data requirements to which a pesticide is subject, the Agency has
grouped pesticides into the following categories: terrestrial,
aquatic, aquatic impact, and forestry uses.
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39
extend beyond the nan-made structures. These consequences may
have an impact on organisms in such environments as holding
ponds, wastewater treatment facilities, and natural or open aquatic
environments, fiquatic impact uses are divided into two categories:
direct discharges, and indirect discharges and wastewater treatment.
(1) Direct discharge. This category includes the practice of
discharging end-use products directly into the natural aquatic
environment in association with their use or the typical method of
disposal of pesticide-treated water. Also included are pesticides
that are discharged into any man-made aquatic facility where the
water is not intercepted by the facility and thus flows directly
into natural or open aquatic environments. Since cooling tower
water is commonly discharged into lakes, streams, and rivers, most
pesticides used to control bacteria or other pests in cooling towers
are considered to have direct discharge uses.
C 2 3 Indirect discharges and wastewater treatments» This
category includes the practice of applying or supplying pesticides
to wastewater treatment facilities where the water is captive, such
as for filter fly control. Water in such facilities is generally
released only occasionally into natural or open aquatic environments.
(e) Forestry uses. Forestry uses involve pesticide applica-
tions to areas that include both terrestrial and aquatic environ-
ments (e.g., woods, marshes, streams) consisting principally of
forest and reforestation sites.
§ 160-4 general'test 'standards.
(a) Overview. The standards contained in this section apply
to all studies in this subdivision unless another section of this
subdivision contains a specific standard on the same subject. In
such a case, the specific standards in the other section apply
to the conduct of that particular study. .!
(b) Test substance. (1) Data submitted in support of an
application for registration shall be derived from tests conducted
with the technical (or purer) grade of the active ingredient, a
radioactively-labeled analytical grade of the active ingredient, or
a typical end-use product, as specified in the test procedure for
the particular test.
(2) Although the guidelines permit use of either radiolabeled
or non-radiolabeled material as the test substance for some studies,
the applicant should be aware that, under almost all circumstances,
use of the radiolabeled test substance would generally be the
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40
logical choice for developing satisfactory data. This is particu-
larly true for studies that require a material balance.
(3) The composition of the test substance should be determined,
including the names and quantities of known contaminants and impuri-
ties, as far as is technically feasible.
(4) The applicant should assign and record lot and sample
number of the test substance.
(5) In addition to or in lieu of testing otherwise required
by this subdivision, the Administrator may require testing to be
conducted with:
(i) fin analytically pure grade of an active ingredient;
(ii) The technical grade of an active ingredient;
(iii) An intentionally added inert ingredient of a pesticide
formulation;
(iv) A contaminant or impurity of an active or inert ingredient;
(v) A plant or animal metabolite or degradation -product of an
active or inert ingredient;
(vi) A pesticide formulation; or
(vii) Any additional substance which could act as a synergist
to the, product for which registration is sought. ' • -:'•••. .:.
(c) Fieldstudies. {1) Location* Field studies should be
conducted in areas considered representative of major areas" where ,,
the pesticide -is intended to be used.
(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.
''(d) Inter-relationship among studies with respectto soil type.
The same soil type should be used for the accumulation study on
rotational crops (§ 165-1), the study of photodegratation on soil
surfaces (§161-3), the aerobic soil metabolism study (§162-1),
the anaerobic soil metabolism study (§ 162-2), the leaching study
(§ 163-t}, and the terrestrial field dissipation study (§ 164-1).
The Agency will consider requests for exceptions to this require-
ment on a case-by-case basis.
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41 ' ' "
§ 160—5 Reporting and evaluation of data.
(a) Overview. This section describes general reporting and
evaluation requirements which apply to studies in the subdivision.
Each test report submitted under this subdivision should satisfy
the reporting requirements of this section, unless a specific
section elsewhere in this subdivision directs otherwise•
(b) Submission. Data submitted in response to 40 CFR Part 158
should be provided in a single report to the extent possible. Any
data that have been furnished in response to the requirements, of
another subdivision and that are also required by this subdivision
either should be referenced to specific pages in other volumes or
should be duplicated and submitted in the volumes containing environ-
mental fate .'data. •
(c) Content. The test report should include a complete and
accurate description of test procedures and evaluation of the test
results. It should also contain a summary of the data, an analysis
of the data,•sufficient data for the Agency to verify calculated
statistical values, and a statement of conclusions to be drawn
from the analysis. The summary should contain sufficient detail to
permit the reader to understand the conclusions of the author. In
addition to the specific information required by || 161-1 through
165-5 of this subdivision, the test report should include the follow-
ing informations
(1) General information* Each report should contains
(i) bates on which study began and ended;
(ii) Name and address of laboratory or institution performing
the testf . .•'.••
(iii) Location where the test was performedi
(iv) Names of principal investigators?
(v) Signatures of each of the senior scientific personnel
responsible for the study; and
(vi) Certification by the applicant that the report is a
complete and unaltered copy of the report provided by the testing
facility.
(2) Test method. Each report should contain a statement
regarding the test method used, including a full, description of
thu experimental design and procedures.
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42
(35 Test substance » (i) The report should identify the test
substance, and should include chemical name and percentage of active
ingredient, molecular structure of the active ingredient, and
qualitative and quantitative description of the chemical composition,
including the results of the analysis conducted in accordance with
§ 160-4(d) (3), when applicable?
(ii) Manufacturer and lot and sample numbers of the test
substances; and
(iii) Properties of the test substance, including physical
state, pH, and stability, when not reported for Subdivision D.
(4) Control Values . Due to the wide diversity of pesticide
properties, use patterns, and organisms likely to be exposed in
the field environment, specific reporting requirements 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.
(5) Test equipment . The report should include a description
of the test equipment used, and photographs or detailed descriptions
of nonstandard equipment.
(6) Units of measurement. Reporting units should be in the
metric system, but the English system may be used, in addition*
In no instance should the systems be mixed (e.g., kilograms/acre).
: Calculations and tabular, 'graphic information* Each
report should contain the "principal mathematical equations used in
'generating and analyzing data> .is' well as representative calcula- . ::
tions 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 correspond-
ing percentages. Rate constants, when required, should be reported
in conjunction with rate data. Tabular data, as well as graphs
for decline curves and soil so rpt ion, should be submitted.
(8) , Analysis for and identification _of degradation products.
Analysis and identification of pesticide residues in field studies
is required only for those degradation products that were found to
form in the lab studies. This position is taken because the purpose
of the lab studies is to identify degradation products and derive
kinetics while the purpose of field studies is to derive levels of
degradation products as a result of pesticide use under field
conditions. Results from the field studies are used in the regulatory
proces s . . ' '•••'•'
(9) Media characteristics . (.i3 Soils . Characterization of
soils utilized in laboratory soil photodegradat ion, metabolism,
and mobility studies, and soils sampled at all field use sites
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43 •
must be reported, including texture (percent sand, silt, and clay) ,
percent organic matter, moisture content, pH, cation exchange
capacity, and bulk density (under field conditions ). Soil from
foreign sources may be used in those lab studies requiring soil,
providing the foreign soil will have the same characteristics
as soil in the United States common to the proposed use area.
Characteristics to be matched are:
0 soil class •
0 % organic matter
0 pH soil
0 ratio of soil bacteria to soil fungi to soil actinomycetes
Field studies are to be conducted in the United States.
Water. In cases of aquatic field tests, characteristics
of water obtained from a use site must be reported (e.g., pH,
temperature, oxygen content, flow rate, and percent suspended
solids } .
(10) Data evaluation. Data submitted from studies described
in this subdivision will be evaluated by the Agency for relevance
to the proposed use, technical adequacy, completeness and overall
scientific value, and will be used in assessing the potential
occurrence of the following environmental hazards:
s
Direct hazards to humans;
Direct hazards to fish and wildlife;
Potexrtial for contaminating groundwater;
Potential for magnification in the food chain; and
Potential for uptake by rotational crops.
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44
Series 161: DEGRADATION STUDIES
§ 161*-1 Hydrolysis studies.
(a) Purpose. Hydrolysis studies are used to establish the
significance of chemical hydrolysis as a route for degradation of
a pesticide and to identify, if possible, the hydrolytic products
formed which may adversely affect nontarget organisms and may
contaminate their food.
(fc) Whenrequired. Hydrolysis data are required by 40 CFR
§158 to support the registration of an end-use product intended
for outdoor or aquatic impact use, and to support each application
for registration of a manufacturing-use product which may legally
be used to formulate such an end-use product. See, specifically,
40 CFR §158.50 and §158.130 to determine whether these data must be
submitted. Section II-A of this Subdivision contains an additional
discussion of the "Formulators1 Exemption" and who must submit
the required data as a general rule.
(c) Test standards. Hydrolysis data submitted in response
to 40 CFR § 158.130 should be derived from tests which comply with
the general test standards of §160-4 of this subdivisions and all
of the following specific test standards:
(1) Test substance. (i) These studies shall be conducted
with each active ingredient in the product*
(ii) Where radioisotopic analytical techniques axe used
(they are preferred), studies shall be conducted with the analytical
grade of. each active ingredient in.the product.
(iii) Where non-radioisotopic analytical techniques are used,
studies shall be conducted with the technical or purer grade of
each active ingredient in the product.
(2) Test procedures. (i) Laboratory hydrolysis studies
should be conducted in darkness.
(ii) One or more concentrations of the test substance should
be used for this study. The concentrations) selected should be
within the aqueous solubility range of the pesticide and at
a level high enough to define the kinetics of the reaction and
also permit isolation and identification of hydrolysis products
formed. However, the maximum concentration(s) selected should
not exceed 250 ppm. For pesticides of low water solubility (less
than 10 ppm), an appropriate solubilizing cosolvent may be added
to increase water solubility. However, use of such agents should
be avoided whenever possible, and, if used, the concentration of
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45
cosolvent in the final solution should not exceed 1 percent by
volume»
(iii) The water used for this study should be free of all live
bacteria, and the glassware should be sterilized to minimize the
possibility of mierobial degradation of the test substance.
(iv) Precautions should be taken during the test to minimize
loss of test substance through volatilization.
(v) The temperature of the hydrolysis reaction should be
maintained at 25 +_ T°C.
(vi) Hydrolysis experiments should be carried out in solu-
tions buffered at pH's of 5, 7, and 9.
(vii) Results of hydrolysis experiments using high concentra-
tions of buffer should be carefully evaluated to determine whether
buffer catalysis effects have occurred.
(viii) Aliquots should be taken at zero time and at sufficient
sampling time intervals to define decline of the pesticide and
appearance of degradates. The duration of the test need not exceed
30 days.
(d) Reporting and evaluation of data. In addition to data
meeting the applicable reporting requirements specified in § 160-5,
the test report should contain the following specific informations
(i) The method of adjusting pH.
(ii) Identification of each hydrolysis product produced in
greater than 10 percent yield at any point during the course of
the study, and material balance and-half-life estimates for the
parent substance.
(e) References. (1) The following references contain
experimental procedures for conducting hydrolysis studies:
(i) Krzeminski, S.P., C.K. Brackett, and J.D« Fisher.
1975. Fate of microbicidal 3—isothiazolone compounds in the
environment: modes and rates of dissipation. J. Agr. Food
Chem. 23:1060-1068. [The effects of temperature and solution pH
on hydrolysis rates are illustrated in this paper.]
(ii) Gomaa, H.M., I.H. Suffet, and S.D. Faust. 1969.
Kinetics of hydrolysis of diazinon and diazoxon. Residue Rev.
29:171-190. [This article contains excellent and concise discus-
sions of the kinetics and mechanisms of acid/base catalyzed
hydrolysis of an organophosphorus pesticide and its products. It
also discusses the effect of temperature on hydrolysis rate, and
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46
illustrates calculation of energies of activation for the hydrolysis
reactions. This article is recommended for information on theory
and development of rate constants» but the more recent and defini-
tive gas chromatographic/mass spectrographic {GC-MS) technique is
recommended for identification of hydrolysis products rather than
the methods used here.]
(iii) Under the Toxic?Substances Control Act, the Agency has
proposed test standards for public review regarding hydrolysis (and
certain other studies). These may be found in 44 FR 16240, (March
16, 11979}, entitled ?Toxic Substances Control: Discussion of
Premanufacturing Testing Policy and Technical Issuesi Request for
Comment."
(iv) [Reserved for: OECD Guidelines for Testing Chemicals.
Section 1, Number 111. Hydrolysis as a Function of pH.]
(v) [Reserved]
(2) Information on GC-MS for identification of pesticides
and products can be found in:
(i) Ryan, J.F. 1977. Residue Analysis Applications of Mass
Spectrometry. Pp. 1-49 in Analytical Methods for Pesticides
and Plant Growth Regulators. IX. Spectroscopic Methods of Analysis.
6. Zweig and J. Shenna (eds). Academic Press, Inc. N. Y.
(ii) Wolfe, N.L., R.G. Zepp, G.L. Baughman, R.C. Fincher, and
J.A* Gordon. 1976. Chemical and Photochemical Transformation of
Selected Pesticides in'Aquatic Systems. Ecological Research Series.
OSEPA 600/3-76-067. 141 pp. [This publication contains reviews
and experiments on the photolysis of various pesticides in water.
Extensive information .is presented that may be useful for the design
of experiments and evaluation of data.]
§ 161-2 ' Photodegradation studies in water.
(a) Purpose. Pesticides introduced into aqueous systems in
the environment can undergo photolytic transformation by sunlight.
Data on rates of photolysis and half-lives are needed to establish
the importance of this transformation process and the persistence
characteristics of photoproducts formed.
(b) When required. Data from a photodegradation study in
water are required by 40 CFR § 158 to support the registration of
an end-use product intended for any terrestrial use (except green-
house and domestic outdoor use), aquatic use, or forestry use, or
for any aquatic impact uses involving direct discharges of treated
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47
water into outdoor aquatic sites* Data from such a study are also
required to support each application for registration of a manu-
facturing-use product which may legally be used to formulate such
an end-use product. See, specifically, 40 CFR § 158.50 and §158.130
to determine whether these data must be submitted. Section II-A of
this subdivision contains an additional discussion of the "Fornula-
tors* Exemption" and who must submit the required data as a general
rule. - .
(c) Test standards». Photodegradation data submitted in
response to CFR §158.130 should be derived from tests which comply
with the general test standards of §160-4 of this Subdivision and
all of the following specific test standards.
(1) Test substance. These studies shall be conducted with
each active ingredient in the product.
(i5 Where radioisotopic analytical techniques are used
(they are preferred), studies shall be conducted with the analytical
grade of each active ingredient in the product.
(ii) Where non-radioisotopic analytical techniques are used,
studies shall be conducted with the technical or purer grade of
-each active ingredient in the product.
•(2) Test procedures. (i) Studies should be conducted at
25+ 1«C.
(ii) One or more concentrations of the test substance should
be used 'for this'study at levels which will define the kinetics of' • .
the reaction and permit isolation and identification of photoproducts
formed. For pesticides of low water solubility, an appropriate
solubilizing co-solvent may be added to increase water solubility.-
'However, use of such agents should be avoided whenever possible,
and, if used, the concentration of co-solvent in the final solution
should not exceed 1 percent by volume. The cosolvent should not
act as a photosensitizer in the rate study.
(iii) Precautions should be taken during.the test to' minimize
loss of test substance through volatilization.
(iv) Photolysis rate determination and photoproduct identifi-
cation experiments should be carried out at a pH that minimizes
hydrolytic breakdown as determined in § 161-1. The pH selected
should be maintained by the use of an appropriate buffer. The
buffer solution should be prepared in distilled or deionized water
free of all live bacteria, and the glassware should be sterilized.
to minimize the possibility of microbial degradation of the test
substance. For compounds that reversibly ionize or protonate
within the pH range of environmental concern, aqueous photolysis
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48
rate determination studies (only) shall be carried out at pH's of 5,
7, -and' 9. •' • : . •-,.'..
(v) Samples should be exposed to either natural or simulated
(including UV greater than 290 nm wavelength) sunlight conditions.
If high intensity radiation studies are conducted to.' allow'shorter
testing periods (e.g., use of Crosby reactor, as described in
reference (i) of paragraph (e) of this section), data should be
provided relating the intensity of the radiation used to that of
natur'al sunlight'*' "•• ••''-- .'••.. - , • /-. •.-.,.. . :-. .. ..•.-'''•••,...'
(vi) Non—irradiated samples of one or more concentrations of
test substance in water held in darkness should be used as experi-
mental controls.
(vii) Aliquots for analysis should be taken at four or more
sampling time intervals, with at least one observation made after
one-half of the test substance is degraded or after the equivalent
of 30 days natural sunlight (12 hours of light per day), whichever
.comes.first.
(viii) A supplemental rate and photoproduct identification study
may also be carried out in the presence of a photosensitizer.
(d) Reporting and evaluation ofdata. In addition to the
applicable information specified in § 160-5, the test report
should contain the following specific information;
(1) If sunlight is used as the light source, a record of the
intensity.of incident sunlight, time of exposure, latitude, time
of year, atmospheric cover, and other major variables which affect
incident light. '' •
(2) If artificial light is used as the light source, the
nature of the source, intensity, wave length distribution, and
time of exposure, as well as the relationship of the light intensity
employed to that of natural sunlight.
(3) Identification of each photoproduct produced in greater
than 10 percent yield at any point during the course of the study,
and material balance and half-life estimates for the parent substance.
(e) References. The following references contain experimen-
tal procedures for conducting water photolysis studies;
(i) Nakagawa, M., and D.G. Crosby. 1974. Photodecomposi-
tion of nitrofen. J. Agr. Food Ghent. 22;849-853. [This detailed
study provides procedures for photolysis of a pesticide in water
under either artificial or natural sunlight.]
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49
(ii) Newsom, H.C., and W.G. Woods. 1973. Photolysis of the
herbicide dinitramine (N3,N3-diethyl-2»4-dinitro-6-trifluQromethyl-_m-
phenylenediamine). J. Agr. Food Chem. 21:598-601. [This article
contains procedures for study of pesticide photolysis in natural
water.] . .
(iii) Niles, G.P., and M.J. Zabik. 1975. Photochemistry of
bioactive compounds. Multiphase photodegradation and mass spectral
analysis of basagran. J. Agr. Food Chem. 23:410-415. [Procedures
for photolysis in aqueous solution, on soil, and as a thin film are
discussed in this article.]
(iv) Su, G.C.C., and M.J. Zabik. 1972. Photochemistry of
bioactive compounds* Photolysis of arylamidine derivatives in
water. 0[. Agr. Food Chem. 20:320-323. [Procedures here are
well defined and useful for a laboratory study of pesticide pho-
tolysis in natural water.]
(v) (Reserved)
(2) Supplemental information for developing a protocol to
conduct a water photolysis study for reentry assessment is given in
the following references:
(i) Wolfe, N.L., R.G. Zepp, G.L. Baughman, R.C. Fincher, and
J.A. Gordon. 1976. Chemical and Photochemical Transformation of
Selected Pesticides in Aquatic Systems. Ecological Research Series.
USEPA 600/3-76-067. 141 pp. [This publication contains reviews and
•experiments.on the transformation of various pesticides in water.
Extensive information is presented that may be-useful for the 'design
of experiments and evaluation of data.]
(ii) Under the Toxic Substances Control Act, the Agency has
proposed test standards for public review regarding photolysis (and
certain other studies). These may be found in 44 FR 16240 {March 16,
1979), entitled "Toxic Substances Control: Discussion of Premanu-
facturing Testing Policy and Technical Issues} Request for Comment."
§ 161-3 Photodegradation studies on soil.
^a' Purpose. Pesticides are applied to the surface of soil
and/or on the exposed surfaces of'plants, and are then subject to
photodegradation. This study will provide data on photolytic pesticide
dissipation and on the nature and persistence of photoproducts formed
by soil surface catalyzed photolysis.
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50
(b) When required. Data from a photodegradation study on soil
surfaces are required by 40 CFR § 158 to support "the registration of
an end-use product intended for orchard crop use, field and vegetable
crop use, or forestry use. Data from such a study are also required
to support each application for registration of a manufacturing-use
product which may legally be used to formulate such an end-use
product. However, such data are not required to support the regis-
tration of end-use products with uses involving application to
soils splely by injection of the product into the soil or by incor-
poration of the product into the soil upon application. See,
specifically 40 CFR §158.50 and §158.130 to determine whether these
data must be submitted. Section II-A of this Subdivision contains an
additional discussion of the "Formulators" Exemption" and who must
submit the required data as a general rule.
(c) Test standards. Soil phdtodegradation data submitted in
response to 40 CFR § 158.130 should be derived from tests which comply
with the general test standards of § 160-4 of this Subdivision and
all of the following specific test standards:
CD Test substance. ISiese studies shall be conducted with
each active ingredient in the product.
(i) Where radioisotopic analytical techniques are used (they
are preferred), studies shall be conducted with the analytical
grade of each active ingredient of the product.
(ii) Where non-radioisotopic analytical techniques are used,*
studies shall be conducted with the technical or purer grade of ...eaten
'active ingredient in the product.
(2) Test procedures, (i) One or more concentrations of the
test substance should be used for this study at levels that will
permit isolation and identification of photoproducts formed.
(ii) One of the soils (e.g., sandy loam, silt loam, or other
soil appropriate to the application site) specified in § 162-1
(Aerobic soil metabolism study) should be used, if data from that
study are also submitted.
(iii) Samples of soil should be exposed to either natural or
simulated sunlight conditions.
(iv) Samples of soil treated with the pesticide at the same
application rate as irradiated soil samples and maintained in darkness
should be used as experimental controls.
(v) Soil samples should be taken for analysis at four or more
sampling time intervals, with at least one observation made after
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51
one-half of the test substance has degraded or 30 days, whichever
cones first. The maximum duration of the study need not exceed
30 days*
(d) Reporting and evaluation of data. In addition to the
applicable information specified in § 160-5, the test report
should contain the following specific information:
(1) If sunlight is used as the light source, a record of the
intensity of incident sunlight, time of exposure, latitude, time
of year, atmospheric cover, and other major variables which affect
incident light.
(2) If artificial light is used as the light source, the
nature of the source, intensity, twave length, distribution, and
time of exposure.
(3) Identification of each photoproduct produced in greater
than 10 percent yield at any point during the course of the study,
and material balance and half-life estimates for the parent substance*
(e) References. (1) The following references contain experi-
mental procedures for conducting soil photolysis studies:
(i) Koshy, K.T., A.R. Friedman, A.L. van der Slik, and D.R.
Graber. 1975* Photolysis of benzoic acid 2-(2,4,6-trichlorophenyl)-
hydrazide. J. Agr. Food Chem. 23:1084-1088. [A procedure for
photolysis of a thin film of pesticide by artificial light is
•described" in 'this- paper.;] •. •••.'.-''.' • ' -
(ii) Niles, G.P.» and M.j; Zabik. 1975. Photochemistry of
bioactive compounds. Multiphase photodegradation and maps spectral
analysis of basagran. J[. Agr. Food Chem. 23:410-415. [Procedures
for photolysis in aqueous solution, on soil, and as a tbjin 'film.are
discussed in this article*]
(2) Under the Toxic Substances Control Act, the A|gency has
proposed test standards for public review regarding
(and certain other studies). These may be found in 44
(March 1S, 1979), entitled "Toxic Substances Control:
of Premanufacturing Testing Policy and Technical Issues;
for Comment." This discussion can provide supplemental
for developing a protocol to conduct a soil photolysis s
photolysis
FR 16240,
Dijscussion '
Request
information
tudy.
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• 52
§ 161-4 Data requirements for photodegradation studies in air.
(a) Purpose. When pesticides are used, humans and other non-
target organisms could be exposed to relatively high concentrations
of pesticide photoproducts in air. This study will provide data
on photolytic pesticide dissipation and on the nature and persistence
of photoproducts formed from pesticides in the vapor phase.
(b) When required. Data from a laboratory photodegradation
study in the vapor phase are required by 40 CFR § 158 on a case-by-
case basis to support the registration of an end-use product in-
tended for orchard or field vegetable crop uses that involve poten-
tially significant exposure to workers. Data from such a study
are also required to support each application for registration of
a manufacturing-use product which legally could be used to formu-
late such an end-use product. The Agency will make an assessment
of what constitutes a significant inhalation exposure of workers
based on the information required by § 163-2{bj(2) of this subdivi-
sion. iSee, specifically, 40 CFR 158.50 and 158.130 to determine
whether these data must be submitted. Section il-A of this Sub-
division contains an additional discussion of the "Formulators"
Exemption" and who must submit the required data as a general
rule. • .' '': '
(c) Test standards« Air photodegradation data submitted in
response to 40 CFR § 158*130 should be derived from tests which
comply with the general test standards in § 160-4 and all of the
following specific test- standards:. • . • . . ' '•• .r;;:;
C1) Test substance. •These studies shall be conducted with
one of the following test substances:
(i) Where radioisbtopic analytical techniques are used (they
are preferred), studies shall be conducted with the analytical grade
of each active ingredient in the product; or
(ii) Where non-radioisptopic analytical techniques are used,
studies shall be conducted with the technical or purer grade of each
active ingredient in the product.
(2) Test procedures, (i) One or more concentrations of the
test substance should be used for this study and at levels that
will permit isolation and identification of photoproducts formed.
(ii) Air samples should be exposed to a. spectrum of light pro-
viding or simulating expected use conditions. Temperature should
be held relatively constant at 30°C.
(iii) Samples of air treated with the pesticide at the same
application rates for irradiated samples and maintained in darkness
should be used as experimental controls.
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53 •
(iv) Air samples should be [analyzed at four or more sampling
tine intervals with at least one observation made after one-half of
the test substance has degraded or 30 days, whichever comes first.
The maximum duration of the study need not exceed 30 days.
(d) Reporting and evaluation of data. In addition to the
applicable information specified in § 160-5, the test report should
contain the following specific information:
(1) If sunlight is used as the light source, a record of the
intensity of incident sunlight, time of exposure, and other major
variables which affect incident light such as latitude, time of year,
and atmospheric cover.
(2) If artificial light is used as the light source, the nature
of the source, intensity, wave length distribution, and time of
exposure.
(3) Identification of each photoproduct produced in greater
than 10 percent yield at any point during the course of the study,
and material balance and half-life estimates for the parent substance.
(e) References. The following references contain information^^
for developing a protocol to conduct an air photolysis study:
(1) Crosby, D.6., and K.w. Moilanen. 1974. Vapor-phase
photodecomposition of aldrin and dieldrin. Arch. Environ. Contain.
Toxicol» 2:62-74. [The reaction vessel described here allows the
investigation of vapor phase photolysis while minimizing the effect
of reactions on vessel walls*]
(2) tinder the Toxic Substances Control Act, the Agency has
proposed test standards for public review regarding photolysis (and
certain other studies). These may be found in 44 FR 16240, (March
16, 1979), entitled "Toxic Substances Control: Discussion of
Premanufacturing Testing Policy and Technical Issues? Request for
Comment."
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54
Series 162s METABOLISM STUDIES
§ 162-1 Aerobic soil metabolism studies.
(a) Purpose. Pesticides which come into contact with soil can
be metabolically transformed. The purpose of soil metabolism studies
is to determine the nature and extent of formation of pesticide
degradation products to which rotational crops and nontarget organisms
will be exposed, and to facilitate assessment of potential disposal
problems.
(b) When required. Data from an aerobic laboratory soil
metabolism study are required by 40 CFR § 158 to support the
registration of an end-use product intended for terrestrial use or
forestry use, and to support each application for registration of a
manufacturing-use product which may legally be used to formulate such
an end-use product. See, specifically, 40 CFR § 158.50 and § 158.130
to determine whether these data must be submitted* Section II-A of
this subdivision contains an additional discussion of the "Formulators"
Exemption" and who must submit the required data as a general use.
(c) Test standards. ' Aerobic -Soil metabolism data submitted 'in
response to 40 CFR § 158.130 should be derived from tests which comply
with the general tests standards in § 160-4 and all of the following
test standards: .
(1) Test substance. The study shall be conducted: using each •;?;
active ingredient in the product. ;*;:i:
(i) If'• radioisotopic analytical techniques .are used, (they are
preferred), the study shall 'be. conducted with the analytical grade
of each active ingredient- in the product.
(ii) If non-radioisotopic analytical techniques -are used, the
study shall be. conducted with the technical or purer grade of each
active ingredient in the product,
(2) Test procedures. (i) Rate, type, and degree of metabolism
.of the pesticide and its major degradates should be determined in a
sandy loam, silt loam, or other soil representative of the soil at
the intended application sites.
(ii) One or more concentrations of the test substance should be
added to soil at levels sufficient to permit measurement of the
disappearance of parent compound and identification of major degradates
formed.
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-55 ' ' .
(iii) Treated soil should be maintained at any constant temperature
between 18 and 30 °C with a recommended soil moisture content at 75
percent of 0«33 bar moisture.
(iv) Preferred soil sampling times are at pre-treatment, at 1,
3, 7, and 14 days, and 1, 2, 3, 4, 6, 9 and 12 months post-treatment.
(v) Sufficient soil samples should be taken at each sampling
interval to ensure interpretable results.
(vi) Residues occurring at a level of 0.01 ppm or greater at
normal field application rates under the label treatment schedule
should be identified when feasible. The Agency realizes that search-
ing for and identifying unknown compounds at the 0.01 ppm level in
environmental substrates is possible for some but not all compounds.
•Therefore, the 0.01 ppm level is to be taken as a suggested goal to
be met or surpassed. However, registration applicants will not be
penalized for not being able to meet the 0.01 ppm goal due to
limitations of the analytical method.
(vii) Data should be collected until patterns of decline of the
test substance and patterns of formation and decline of degradation
products are established in soil, or for one year, whichever comes
first, when terrestrial crop, noncrop, and forestry uses are involved.
an aerobic soil metabolism study extending to two half-lives of the
test substance or to six months duration, whichever comes first, is
required for pesticides intended only for greenhouse uses and/or
domestic outdoor uses.
{d) Reporting and evaluation of- data. In addition to the
applicable reporting-requirements specified in § 160-5, the test
report should contain the following specific information: ~"
{1) Representative residue data for soil samples analyzed in
accordance with paragraph (c)(2) of this section?
(2) Soil temperature;
(3) Description of soil source and characteristics!
(4) Material balance?
(5) Half-life estimates?
(6) Identity of residues occurring at levels of 0.01 ppm or
greater; and
(7) Residue decline curves.
(e) References. (1) The following references contain experimental
procedures for conducting aerobic soil metabolism studies:
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56
(i) Bartha, R., and D. Kramer. 1965. Features of a flask
and method for measuring the persistence and biological effects of
pesticides in soil. Soil Sci. 100;68-70. [The apparatus described
in this paper provides a simple, rapid method for demonstrating
microbial degradation, persistence, and relative toxicity of a
xenobiotic in soil under laboratory conditions.]
(ii) Betts, P.M., C.W. Giddings, and J.R. Fleeker. 1976. De-
gradation of 4-aminopyridine in soil. J. Agr. Food Chem. 24:571-574,
[This paper contains procedures for study of radio-labeled pesticide
in soils and in cultures of soil microorganisms*]
(iii) Ferris, Ian G., and I. Paul Lichtenstein, 1980. Interac-
tions between agricultural chemicals and soil microflora and their
effects on the degradation of [14C]-parathion in a cranberry soil.
J. Afric. Food Chem. 28s1011-1019. [This paper illustrates the
importance of interactions of soil microorganisms and agricultural
chemicals in the degradation of other pesticides,and contains
procedures for necessary investigations The procedures include
methods for treatments and incubation of soil, for trapping of
volatile products, for extraction of materials from soil, and for
'analyses.] ,'•'•• ' : - : '. ', ' '• : -. . • -
(iv) Fleeker, J.R«,H.M. lacy, I.R. Schultz, and E.G. Houkom.
1974. Persistence and metabolism of thiophanate-methyl in soil.
J. Agr....... Food Chem. 22s592-595. [The soil metabolic procedures in
this paper are recommended for development of a protocol.]
(v) Parr, J.F., and S. Smith. 1969. A multipurpose mani-
fold assembly: Use in evaluating microbiological effects of pesti-
cides.' Soil Sci .107; 271-'276. [The procedure here, is useful for
soil respiration studies, and the style and directions are clear.]
(vi) Parr, J.F. and S. Smith. 1973. Degradation of triflura-
lin under laboratory conditions and soil anaerobiosis. Soil Sci.
115j55-63. [This paper contains a procedure for the investigation
of metabolism of a pesticide in soil using the apparatus discussed
in Parr and Smith (1969). The procedures contained in this paper
are reported to allow separation of effects of volatilization,
photolysis, and nonbiological degradation from microbiological
metabolism with respect to dissipation of a pesticide from soil.]
(vii) Schooley, D.A., K.M. Creswell, L.E. Staiger, and G.B.
Quistad. 1975. Environmental degradation of the insect growth
regulator isopropyl (2E,4E)-ll-methoxy-3,7,11-trimethy!2,4-dodeca-
dienoate (methoprene). IV. Soil Metabolism. J. Agr. Food
Chem. 23:369-373. [This is an excellent study, and contains proce-
dures for investigation of metabolism of a pesticide in soil.]
(viii) Smith, R.A., W.S. Belles, K.W. Shen, and W.G. Woods.
1973. The degradation of dinitramine (N3,N3-diethyl 2,4~dinitro-6-
trifluoromethylm-phenylenediamine) in soil. Pest. Biochem. Physiol.
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57
3:278-288. [The procedures reported in this study were well planned
and executed, and they describe the required tests.]
(ix) Starr, R.I., and D.J. Cunningham. 1975. Leaching and
degradation of 4-aminopyridine-^4c in several soil types. Arch.
Environ. Contam. Toxicol. 3s72-83. [This paper provides a procedure
for a soil metabolism study with a radio-labeled pesticide using
soils varying in pH, organic matter content, and sand-silt-clay
content.]
(2) Supplemental information for developing a protocol for the
determination of non-extractable residues is given in the following
references: (i) Kazano, H., P.C. Kearney, and D.D. Kaufman.
1972. Metabolism ofmethylcarbamate insecticides in soils. J.
Agr. Food Ghent, 20t975-979* [Among the points of special considera-
tion in this study are the reporting of soil characteristics, the
flow sheet and detail of experimental work, and the reporting of
recoveries of parent compound and metabolite from soil.]
(ii) Stevenson, F.J. 1965. Gross Chemical Practionation of
Organic Matter. Pp. 1409-1421 in Methods of Soil Analysis. C.A.
Black, D.D. Evans, J.L. White, L.E. Ensminger, and F.I. Clark (eds.).
Amer. Soc, Agron. Publ. No. 9. Madison, Wisconsin. [The procedures
outlined in this publication may be useful for isolation of and
accounting for pesticide added to soil. However, care must be
exercised when interpreting metabolism from extracts done with acid
or alkali, since artifacts can arise with such drastic extraction
procedures»] '
§ 162-2' Anaerobic soil_metabg_lisn studies.
(a) Purpose. The purpose of an anaerobic soil metabolism
study is to determine the rate .and pattern of pesticide metabolism
under anaerobic conditions. This information is used to ascertain
effects of flooding or waterlogging on a'well-aerated soil, a
condition which can have an effect on many oxidation-reduction
systems that, in turn, may indirectly affect pesticide metabolism
and fate.
(b) When required. (1) Data from an anaerobic soil metabo-
lism study are required by 40 CFR § 158 to support the registration
of an end-use product intended for field-vegetable crop use, and
to support each application for registration of a manufacturing-use
product which any legally be used to make such an end-use product.
See, specifically, 40 CFR § 158.50 and §158.130 to determine whether
these data must be submitted. Section II-A of this Subdivision contains
an additional discussion of the "Formulators1 Exemption" and who
must submit the required data as a general rule.
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(2) Data from an anaerobic soil metabolism study need not be
submitted if data from the anaerobic aquatic metabolism study
described in f 162.3 of this subdivision have been submitted.
(c) Test standards. Anaerobic soil metabolism data submitted
in response to 40 CPR § 158.130 should be derived from tests which
comply with the general test standards in § 160-4 and all of the
following specific their test standards:
(1) Test substance. This study shall be conducted using each
active ingredient in the product.
(1) if radioisotopic analytical techniques are used (they are
preferred)f studies shall be conducted with the analytical grade
of each active ingredient in the product.
(ii) If non-radioisotopic analytical techniques are used,
studies shall be conducted with the technical or purer grade of
each active ingredient in the product.
(2) Test procedures, (i) The study should be conducted on
the same soil selected for testing in the aerobic soil metabolism
study, 5 162-1, if data from that study are also submitted.
(ii) A sample of the soil treated with one or more concentra-
tions of the test substance and incubated for 30 days or one half-
life ( whichever is shorter) should be converted from aerobic to
anaerobic conditions by either water-logging or purging the soil
with inert gases. Where organic content of the soil is deficient, •"•&••••'•'
organic amendments should be supplied to the treated soil within
30 days to ensure a substrate for anaerobic metabolism.
(iil) Treated soil should be maintained at a constant temperature
between 18 and 30°C after anaerobic conditions have been established.
(The temperature chosen should be the same as that selected in the
aerobic soil metabolism study § 162-1, if that study is also required.)
(iv) Preferred sampling intervals are 30 and 60 days after
anaerobic conditions have been established.
(v) The length of the study need not extend beyond 60 days.
(vi) Residues occurring at a level of 0.01 ppra or greater at
normal field application rates under the label treatment schedule
should be identified, when feasible [refer to § 162-1(c)(2)(vi)].
(d) Reporting and evaluation of data. In addition to the
applicable reporting requirements specified in § 160-5, the test
report should contain the following specific informations
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(1) Representative residue data for soil samples analyzed
in accordance with paragraph (c)(2) of this section.
(2) Selected soil temperature;
(3) Description of soil source and characteristics?
(4) Material balance}
(5) Half-life estimates;
(6) Identity of residues occurring at levels of 0.01 ppm or
greater;
(7) Residue decline curves*
(e) References. (1) The following reference contains experi-
mental procedures for conducting anaerobic soil metabolism studies:
Gowda, T.K.S., and N. Sethunathan. 1976. Persistence of endrin
in Indian rice soils under flooded conditions. J. Agr. FoodChem.
24s750-753. {Procedures are reported in this publication for the
study of relative persistence of a pesticide in several flooded
soils. This paper also provides information of the effects of pH,
organic matter content, and microorganism metabolism on persistence
of the compound.]
(2) Refer to § 162-1(e) for further references on methods to
conduct soil metabolism studies.
§ 162-3 .'Anaerobic aquatic metabolism studies.
Purpose. The purpose of an anaerobic aquatic metabolism
study is to assess the nature and extent of formation of pesticide
residues in water and in hydrosoil, since these residues may then
be taken up by irrigated crops and passed on to other parts of the
aquatic food web. Anaerobic conditions are more likely to prevail
where pesticides are found in aquatic environments than in strictly
terrestrial environments.
(b) When required. Data from an anaerobic aquatic metabolism
study are required by 40 CFR § 158 to support the registration of
an end-use product intended for aquatic use, forestry use, or for
any aquatic impact uses involving direct discharges .of treated
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water into outdoor aquatic sites. Data from such a study are also
required to support each application for registration of a manufac-
turing-use product which may legally be used to make such an end-use
product. See, specifically, 40 CFR § 158.50 and § 158.130 to determine
whether these data must be submitted. The anaerobic soil metabolism
study in § 16-22 of this Subdivision may not be substituted for
this study. Section II-A of this subdivision contains an additional
discussion of the "Formulators' Exemption" and who must submt the
required data as a general rule.
(c) Test standards. Anaerobic aquatic-metabolism data sub-
mitted in response to 40 CFR § 158.130 should be derived from tests
which comply with the general test standards in § 160-4 and all of
the - following test standards:
(1) Test substance. This study shall be conducted using each
active Ingredient in the product•
(i) If anaerobic analytical techniques are used (they are
preferred), studies shall be conducted with the analytical grade
of each active ingredient in the product.
(.ii) If non-radioisotopic analytical techniques are used,
studies shanr~be conducted with the technical or purer grade of
each active ingredient in the product.
(2) Test procedures. (i) Rate, type, and degree of meta-
bolism of the pesticide should be determined in the laboratory in
water plus sediment obtained from and representative of that found
at an intended use site. The preferred substrate for this laboratory
study is sediment covered with water, but the use of a flooded
soil may be adequate.
(ii) If the test is performed using flooded soil, oxygen
depletion should be established by flooding for 30 days prior to
adding the test substance. The test substance should be applied at
a rate sufficient to permit measuring the disappearance of.the
parent compound and identification of major degradates« Where
organic content of the soil is deficient, organic amendments should
be supplied within 30 days of application of test substance to
ensure a substrate for anaerobic metabolism.
(iii) Treated soil/sediment should be maintained at any constant
temperature between 18 and 30°c.
(iv) Data should be collected until patterns of decline of the
test substance and patterns of formation and decline .of degradation
products are established in water and sediment, or for one year,
whichever comes first.
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(v) Residues occurring at a leyel of 0.01 ppm or greater at
normal field application rates under the label treatment schedule
should be identified, when feasible. [Refer to f I61-l{c) (2Mvi)]
(d) Reporting and evaluation ofdata. In addition to the
applicable reporting requirements specified in § 160-5, the test
report should contain the following specific information:
(1) Representative residue data for water and sediment sam-
ples analyzed in accordance with paragraph (c)(2) of this section*
(2) Soil/sediment temperature, and
(3) Description of soil/sediaent/water source and charac-
teristics;
(4) Material balance;
(5) Half-life estimates;
(6) Identity of residues occurring at levels of 0.01 ppm or
greater; and
(7) Residue decline curves.
(e) References. The following references contain experimen-
tal procedures for conducting anaerobic aquatic metabolism studies;
(i) • . Gowda, X»K*S*, and N. Sethunathan. 1976. Persistence of
endrin in.Indian rice soils under''flooded conditions. J. Agr.
Food Chem. 24;750753. [Although the procedure used in this study
can provide useful information, it is not necessary to measure the
redox potential to establish anaerobiosis if the 30-day flooding
requirement is met.]
(ii) Hance, R.J., and G. Chesters. 1969. Ihe fate of hydroxya-
trazine in a soil and a lake sediment. Soil Biol. Biochem. 1:309-315.
[Although this is a study of a metabolite rather than a pesticide,
it is a useful model to illustrate use of a sediment and a soil,
establishment of anerobiasis by use of streams of nitrogen or
air, comparison of aerobic and anaerobic aquatic metabolism, and
use of sterile and inoculated media for study of metabolism with a
radio-labeled compound.]
(iii) Miyazaki, S., H.C. Sikka, and R.S. Lynch. 1975. Meta-
bolism of dichlobenil by microorganisms in the aquatic environment.
J. Agr. FoodChem. 23:365-368. [This report provides a good
model on which to base experimental protocols.]
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62
| 162-4 Aerobic aquatic metabolism studies*
Purpose. The purpose of aerobic aquatic metabolism
studies is to determine the effects on a pesticide of exposure to
aerobic conditions in water or sediment during the period of dis-
persal of the pesticide throughout the aquatic environment, and to
compare rates and formation of metabolites with those observed
under conditions of anaerobic aquatic metabolism.
,;•"'>.'-.. x . ' • "••>
(b) Whenrequired. Data from an aerobic aquatic metabolism
study are required by 40 CFK §158 to support the registration of an
end-use product intended for aquatic use or for any aquatic impact
uses involving direct discharges of treated water into outdoor
aquatic sites, and to support each application for registration of
a manufacturing-use product which may legally be used to formulate
such an end-use product. See, specifically, 40 CFR § 158.50 and
§ 158.130 to determine whether these data must be submitted. Section
II-A of this Subdivision contains an additional discussion of the
"Formulators' Exemption" and who must submit the required data as a
general rule. •" • "••'••••"• :
(c) Teststandards. Aerobic aquatic metabolism data submit-
ted in response to 40 CFR § 158.130 should be derived front tests which
comply with the general test standards in § 160-4 and all of the
following specific test standards:
{1) Test substance. This study shall be conducted using each
active ingredient in the product. "
(i) If radioisotopic analytical techniques are used (they are
preferred), studies shall be conducted with the analytical grade
of each active ingredient in the product.
(ii) If non—radioisotopic analytical techniques are used,
studies shall be conducted with the technical or purer grade of
each active ingredient in the product.
(2) Test procedures» (i) Pesticide metabolism should be de-
termined in the laboratory in water plus sediment obtained from
and representative of that found at an intended use site. The
test substance should be added to water at a rate sufficient to
permit measuring the disappearance of the parent compound in water
and identification of major degradates in water and sediment.
(ii) The treated water/sediment should be maintained at a con-
stant temperature between 18 and 30 °C. (The temperature chosen
should be the same as that selected in the anaerobic aquatic metabo-
lism study, § 162-3, if that study is also being conducted.)
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(iii) Data should be collected until patterns of decline of the
test substance and patterns of formation and decline of degradation
products are established in water and sediment or for 30 days,
whichever comes first.
(iv) Residues occurring at a level of 0.01 ppm or greater at
normal field application rates under the label treatment schedule
should be identified, when feasible [Refer to § 162-l(c)(2)(vi)J.
(v) For additional procedures and supplementary information
on aerobic aquatic metabolism studies, see § 162-4(e).
(d) Reporting and evaluation of data* In addition to data
submitted in response to the applicable reporting requirements
specified in § 16-05, the test report should contain the following
specific informations
(1) The results of analysis of each water and sediment sample
required in paragraph (c){2) of this section;
(2) Soil/sediment temperaturei
(3) Description of soil/sediment/water source and characteristics;
(4) Material balance?
(5) Half-life estimatesi
(6) Identification of residues occurring at levels of 0.01
ppm or.greater; and
(7) Residue decline curves.
(e) References. The following references contain experimen-
tal procedures for conducting aerobic aquatic metabolism studies:
(1) Krzeminski, S.F., O.K. Brackett, and J.D. Fisher. 1975.
Fate of microbial 3—isothiazolone compounds in the environment:
Modes and rates of dissipation. J. Agr.Food Chem. 23:1060-1068,
(2) Krzeminski, S.F., C.K. Brackett, J.D. Fisher, and J.F.
Spinnler. 1975. Fate of micccrobicidal 3-isothazolone compounds
in the environment: Products of degradation. J. Agr. Food Chem.
23:1068-1075.
[These two papers in combination constitute an excellent model for
an aerobic metabolic study* The papers compare degradation and
accumulation in several systems and contain an extensive compilation
of well-identified metabolites. Of special interest is the inhibition
and induction in metabolism reported here.]
(3) Schaefer, C.H., and E.F. Dupras, Jr. 1976. Factors
affecting the stability of dimilin in water and the persistence of
diailin in field waters. J. Agr. Food Chem. 24:733-739.
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64
Series 163; MOBILITY STUDIES
§ 163-1 Leaching and adsorption/desorption studies.
(a) Purpose* The movement of pesticide residues by means of
leaching through the soil profile or transport to and dispersion
in the aquatic environment may cause contamination of food, result
in loss of usable land and water resources to man due to contamina-
tion of groundwater supplies, or cause habitat loss to wildlife.
Therefore, laboratory studies are required to predict:
(1) The leaching potential or pesticides and their degradates
through the soil profile at terrestrial sites; and
(2) The movement of pesticides and their degradates to and
dispersion in aquatic sites.
(b) When required. Leaching or absorption/ desorption data
are required by 40 CFR § 15S to support the registration of an end-
use product intended for domestic outdoor use , greenhouse use,
terrestrial noncrop use, orchard crop use, field-VegetafsTe~crop
use, forestry use, aquatic use, and aquatic Impact uses involving
direct discharges of treated water into outdoor aquatic sites.
Such data are also required to support each application for
registration of a manufacturing— use product which may legally be
used, to make., such an end-use product*.'". See, specifically, '40 CFR
f 158.50 and § 158.130 to determine whether these data must be
submitted. Section II-A of this Subdivision contains an additional
discussion of the "Formula tors" .Exemption" and who must submit the
•.required data .as a general; rule*
. • .'. • • (-c) Test standards. 'Leaching or absorption/ desorption data
submitted in response to 40 CFR § 158.130 should be derived from
tests which comply with the general test standards in § 160-4 and
all of the following specific test standards:
{ 1 ) Test substance. Studies shall be conducted using each
active ingredient in the product.
(i) If radioisotopic analytical techniques are used (they are
preferred) , studies shall be conducted with the analytical grade of
each active ingredient in the product;
(ii) If non-radioi so topic analytical techniques are used,
studies shall be conducted with the technical or purer grade of
each active ingredient in the product.
Test procedure, (i) Analytical technique selection . A
laboratory study should be conducted to provide a quantitative
estimate of pesticide mobility in soil or absorption/ desorption on
sediments.- ".•/' ' ' •
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Amount of test substance.An amount of test substance equal
to the highest recommended rate for a single application of the
pesticidal active ingredient should be added to the soils/sediment
utilized in these studies.
(iii) Soil selection. Each study should include, at a minimum,
four soils, such as sand (agricultural), sandy loam, silt loam,
clay, or clay-loam, each having a pH within the range of 4-8.
•However, if the pesticide is to be limited to use with one specific
soil type, then the soils selected should include that specific
soil type. In addition, if the pesticide is intended for an aquatic
use or for an aquatic impact use involving direct discharges of
treated water into outdoor aquatic sites, batch equilibrium
(adsorption/desorption) studies on one aquatic sediment obtained
from or representative of the proposed use area should be provided.
(A) At least one of the soils selected should have an organic
matter content less than or equal to one percent (sand or sandy
loam preferred).
(B) One of the soils should be the soil used for § 162-1
(aerobic soil metabolism study). This soil preferably should be a
sandy-loam soil. This soil shall be used to study leaching of
pesticide degradates.
(iv) Preparation of soil for study of pesticide degradates.
The test substance should be aged under aerobic conditions for 30
days or one half-life (whichever is shorter), in the soil selected
in paragraph (c)(2)(iii)(B) of this section. The treated soil
should be maintained at a constant temperature between 18 and 30°C.
The -temperature chosen-shall be the same as that selected in the
aerobic soil metabolism study § 162-1) if that study is also
required. The treated soil should be maintained at a soil moisture
content of 75 percent of 0.33 bar moisture content during the aging
period. At the end of the aging period, either a portion of the
aged soil containing the pesticide and its degradates or extracts
obtained from the aged soil should be tested by one of the methods
set forth below:
(A) The extract may be tested on soil thin layer chromato-
graphic (TLC) plates as required by paragraph (c)(2)(v)(A) of this
section; or
(B) The portion of aged soil may be added to the prepared
soil columns as required by paragraph (c)(2)(v)(B) of this section;
or .' ' - .
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66
(C) Alternatively, the mobility of individual degradates which
have been demonstratee independently to occur in soil after the
aging period specified in paragraph (c)(2)(v) of this section.
(v) Analysis methods. For terrestrial noncrop uses, orchard
crop uses, field-vegetable crop uses, and forestry uses, the mobility
of the test substance and its degradates in soil should be assessed
either by soil thiri layer chromatography, soil column, or batch
equilibrium (adsorption/desorption) procedures described below in
paragraphs (A), (B), and (C)» respectively. For domestic outdoor
uses, greenhouse uses, aquatic uses, and aquatic impact uses, the
mobility of the test Substance and its degrada€es in soil shall be
assessed only by the batch equilibrium (adsorption/desorption)
procedure. Whatever procedure is selected must be followed for
all soils' studied. ' •''••' ; '• - : •'&•-* •':" ...•••'
(A3 Soil thin-layer chronatography (TLC) study. Soil TLC
studies to predict the leaching potential of pesticides and their
degradates in soil should be performed as followss TLC plates
should be prepared using the soils described in paragraph (c)(2)(iii)
of this section, to which both the test substance (parent pesticide
and degradates) are applied. Application of reference pesticide
standards on each TIC -plate in addition to the test substance is
required, to assess the relative mobility of the test substance to
that of other pesticides whose laboratory and field leaching behavior
is already known. For experimental procedures on soil and plate
preparation, pesticide application, plate development, pesticide
visualization, and Rf calculations, see reference (1)(ii) of
paragraph (e) of this'section. '' ; ''•*' ' • '. '• ••'•••
(B) Soil:'column study. '''.Soil column studies1 to define the
vertical distribution of the test substance and its degradates in
the soil profile should be!performed as followst The column(s)
should be from 30 to 300 cm in height, consisting of soils described
in § 1631(c)(2)(iii), and should be eluted with a volume of water
equal to [groundwater recharge values of] 20 inches (50.8 cm)
times the cross sectional area of the column* A distribution
curve of the test substance in the column shall be determined by
quantification of the test substance and its degradates in 6 cm
segments and in the eluate. For experimental procedures on conducting
a. soil column study, see references (1)(i), (iii), (iv) and (v) of
paragraph (e) of this section.
(C) Batch equilibrium fadsorption/desorption) study. Adsorp-
tion/desorption coefficients calculated from a batch equilibrium
study are used along with solubility data to predict the extent or
depth of pesticide leaching in the different soil types tested,
and also the extent of pesticide adsorption/desorption on sediments
when aquatic or aquatic impact uses are proposed. The study should
be conducted using the soils described in paragraph (c)(2)(iii) of
this section, plus one representative aquatic sediment (if an
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67
aquatic or aquatic impact use involving direct discharge is proposed).
The test substance including its degradates identified in and
extracted from the aerobic soil metabolism-study {§ 162-1) should
be equilibrated with the soils and aquatic sediment selected for
this study at four concentrations in a 0.01 N or M Ca ion solution.
If necessary, a small amount of acetone or other solvent may be
used to achieve solution of poorly soluble pesticides or degradates.
For experimental procedures on conducting batch equilibrium (adsorp—
tion/desorption) studies, including calculation of Kd values, see
references (3)(i) through (xii) and (4)(i) and (ii) of paragraph
(e) of-this section.
(d) Reporting and evaluation of data. In addition to the
applicable reporting requirements specified in § 160-5, the test
report should contain the following specific information:
(1) Soil thin layer chromatography (TLC). The mobility of
pesticides and their degradates should be reported as mobility
class 1 to 5, corresponding to Rf values of 0.0 to 0.09 [immobile
(class 1)]» 0.10 to 0.34 [low (class 2)], 0.35 to 0.64 [intermediate
(class 3)3, 0.65 to 0.89 [mobile (class 4)] ,-;,,and 0.90 to 1.0 [very ,
mobile (class 5)], respectimely. Values of soil/water relationships
(K(j) should be repcirted using appropriate Rf to KQC/K^ equations.
Examples of calculations used in determining K
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68
(ii) Helling, C.S. 1971. Pesticide mobility in soils. I.
Parameters of thin-layer chromatography. Soil Sci. Soc.Amer. Proc.
35s 732-737. [This paper discusses the usefulness of soil thin-layer
chromatography and details experimental parameters.]
(iii) Krzeminski, S.F., C.K. Brackett, and J.D. Fisher. 1975.
Fate of microbicidal 3-isothiazolone compounds in the environment:
modes and rates of dissipation. J. Agr. FoodChem. 23:1060-1068.
[Shis paper contains a procedure for a column leaching study.]
(iv) Lichtenstein, E.P., K.R. Schulz, and T.W. Fuhremann.
1972. Movement and fate of dyfonate in soils under leaching and
nonleaching conditions. J. Agr. Food Chem. 20:831-838. [Both GLC
and radio-tracer analyses were used in this study with radio-labeling
in two positions to allow illustration of different types of degra-
dation products and their movement in soils.]
(v) Weber, J.B., and T.F. Peeper. 1977. Herbicide Mobility
in Soils, Pp. 73-78 in Research Methods in Weed Science. B.
Truelove (ed.). S. Weed Sci. Soc. Second Edition. Auburn Printing,
Inc. Auburn, Alabama. [This paper provides a brief but descriptive
analysis of procedures for the study of herbicide leaching in
soil, and it discusses the two major types of columns used for
these studies'. ' • . • . •'-.-.•.' •;.,.. -
(2) The following references contain supplemental information
pertaining to mobility studies:
(i) Bailey, G.W., and J.L. White. 1970. Factor influencing the
adsorption and movement of • pesticides in soils. Residue Rev. 32::29—
92. [This is a- good' general review discussing -pitfalls to be aware
of in planning or interpretation of leaching experiments.] .
(ii) Hamaker, J.W., and J^M. Thompson. 1972. Adsorption. Pp.
49-143 in Organic Chemicals in the Soil- Environment. Vol. I. C.A.I.
Goring and J.W. Hamaker (eds.). Marcel Dekker, Inc., New York.
[This is a basic review of the theoretical foundation of pesticide
adsorption on soils and an excellent source for equations and the
derived constants characterizing pesticidesoil adsorption. The tables
of data may aid in initial range-finding.]
(iii) Leistra, M., and W.A. Dekkers. 1976. Computed effects
of adsorption kinetics on pesticide movement in soils. J.SoilSci.
28:340-350. -[This is a. theoretical paper that may be useful for
interpretation of leaching studies, since it illustrates the importance
of rainfall pattern'with respect to pesticide leaching.]
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69 ..
(iv) Leistra, M., J.J. Smelt, and R» Zanvoort. 1975. Per-
sistence and mobility of bromacil in orchard soils. Weed Res.
15:177-181. [This article is recommended for those planning and
intarpreting pesticide leaching experiments. It reports that the
leaching of a pesticide in field experiments was substantially
lower than predicted by calculation from results of soil-TLC
experiments.] • .• . •
(v) Lindstrom, p.T., L. Boersma, and P. Stockard. 1971* A
theory on on the mass transport of previously distributed chemicals
in a water saturated sorting porous medium: Isothermal cases.
Soil Sci. 112:291-300. [This paper presents a theoretical model
for predicting pesticide movement from adsorption data and flow
rates.] • -: jfj- -^ ••••...
(vi) Oddson, J.K., J. Letey, and L.V. Weeks. 1970. Predicted
distribution of organic 'chemical in solution and adsorbed as a function
of position and time for various chemical and soil properties. Soil
Sci. Soc. Amer. 34:412-417. [This paper presents a theoretical model
for the movement of•pesticides in soils.]
(vii) Van Genuchten, H.T., P.J. Wierenga, and G.A. O'Connor.
1977. Mass transfer studies in sorbing media: III. Experimental
evaluation with 2,4,5-T. Soil Sci. Soc. Amer. 41:278-285. [This
paper presents comparisons of model calculations and experimental
data, and it may be->useful for planning or interpretation of leaching
experiments.] ,*" ' ' •
' • ' ' r,» 'I '
4 " " •' ' ' • • • • . '
(3) The following references contain experimental procedures for
conducting adsorption/desorption studies:
(i) Aharonson, N., and U. Kafkafi. 1975.. Adsorption, mobi-
lity and persistence of'. thiabendazole and methyl 2-benzJjmidazolecar-
bamate in soils. J. Agr. Food Chen. 23:720-724. [The techniques
and methods used in this study are useful for both adsorption/d
esorption and leaching studies.]
(ii) Farmer, W.F., and Y. Aochi. 1974. Picloram sorption
by soils. Soil Sci. Soc. Amer. Proc. 38:418-423. [Methods of
adsorption and deterption can be found in this study.]
(iii) Grover'^ R., and R.J. Hance.. 1970. Effect of ratio of
soil to water on, adsorption of linuron and atrazine. Soil Sci.
109:136—138. [This paper presents information on the soil-water
ratio to be used in laboratory studies of pesticide adsorption to
SOilS.] ' . . ;
(iv) Hamaker, J.W., C.A.I. Goring, and C.R. Youngson. 1966.
Sorption and leaching of 4-amino-3,5,6-trichloropicolinic acid in
soils. Advances in Chemistry Series 60:23-37. [The techniques
and methods used in this study are standard except for the time
allowed for equilibration. The data presented demonstrates'the
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70
effect of pH on adsorption of an ionized species and the inverse
relationship between partition coefficient and adsorption.]
(v) Hance, R.J. 1967. The speed of attainment of sorption
equilibria in some systems involving herbicides. Weed,Res. 7:29-36.
[This study illustrates the use of range finding experiments to
find an equilibration time for meaningful adsorption experiments.
Techniques for adsorption and desorption experiments and use Q"£
Freundlich isotherms are presented in this paper.]
(vi) Harvey, R.G. 1974. Soil adsorption and volatility of
dinitroanilineherbicides. Weed Sci. 22:120-124. [Use of absorp-
tion isotherms for the calculation of latent heat of adsorption
and the effect of adsorption -on volatility of pesticides are il-
lustrated in this paper.] .
(vii) Leistra, M., and WiA. Dekkers. 1976. Computed effects
of adsorption kinetics on pesticide movement in soils. J» SoilSci.
28:340-350. [This is a simulation of pesticide behavior on soils in
the field by computer.]
(viii) Leistra, M., and W.A. Dekkers. 1977. Some models for
the adsorption kinetics of pesticides in soil. J. Environ. Sci.__
Health B12(2):85~103. [This continuation of the 1976 paper (above)
discusses the multimechanism, multirate phenomena responsible for the
differences observed in rates of adsorption and rates of desorption.]
: (ix) Murray, D.S., P.W. Santelmann, and iJ.M. Davidson. 1975.
Comparative adsorption, desorption, and mobility of dipropetryn
and prometryn in soil. J-» AgxV Food Chen* 23:578-582. [The cor-
relation between adsorption, cation exchange capacity, organic
matter, and clay content is illustrated in this paper,, and adsorp-
tion/ desorption is compared with soil TLC experiments.]
(x) Saltzman, S., L. Kliger, and B. Yaron. 1972. , Adsorption/
desorption of parathion as affected by soil organic matter. J. Agri.
Food Chem. 20:12241226. [The importance of organic matter in absorp-
tion of pesticides by soil is discussed in this report.]
(xi) Savage, K.E>,' and R.D. Wauchope. 1974. Fluometuron ad-
sorption/ desorption equilibria in soil. Weeds 22:106-110. [This
paper discusses equations used for computation of adsorption
isotherms and provides information for equation selection for
quantitative depiction of adsorption and desorption.]
(xii) Wu, C.H., N. Buehring, J.M. Davidson, and P.W. Santelmann.
1975. Napropamide adsorption, desorption, and movement in soils.
Weed Sci. 23:454457. [Column'leaching and soil TLC experiments
conducted and reported here are correlated with adsorption/desorption
experiments.]
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' ' '71. • :,: :.- '
(xiii) (Reserved for: OECD Guidelines for Testing Chemicals. Section
1, Number 106. Adsorption/Desorption.)
(4) The following references contain supplemental informa-
tion for developing a protocol for adsorption/desorption studies:
(i> Bailey, G.W., and J.L. White. 1970. Factors influenc-
ing the adsorption, desorption, and movement of pesticides in
soils. Residue Rev. 32: 29-92. [This review provides background
information on the principles underlying the processes of adsorption
and mobility of pesticides in soil.]
(ii) Weber, J.B. 1977. Soil Properties, Herbicide Sorption,
and Model Soil Systems. Pp. 59-72 in Research Methods in Weed
Science. 2nd Id. S. Weed Sci. Soc. B. Truelove (ed). Auburn
Printing, Inc. Auburn, Ala. [This is a general review of experi-
mental methods for determination of soil properties, herbicide
adsorption, and construction of simple model soil systems.]
§ 163-2 Laboratory volatility studies.
(a) Purpose« Volatilization can be a major mode for the move-
ment of pesticides from treated areas. The vapors resulting from
volatilization of some pesticides can cause adverse effects to man
via inhalation .exposure at sites of application or biological
effects in nontarget organisms at some distance from the treated
site. The Agency is particularly concerned about commercial green-
house applications involving intensive use of volatile pesticides,
use patterns which .are characteristically, involved with commodities
having high economic value and high labor requirements; .such uses
can result in significant inhalation exposure to workers and appli-
cators." • •.... •.•-•
(b) When required. (1) .Data"from a laboratory volatility
study are required by 40 CFR § 158 on a case-by-case basis to
support the registration of each end-use product intended for
commercial greenhouse, orchard, or field-vegetable crop uses that
involve significant inhalation exposure to workers. Data from
such a study are also required to support each application for
registration of a manufacturing-use product which may legally be
used to formulate such an end-use product. See, specifically, 40
CFR § 158.50, § 158.130, and "the following discussion in § 163.3-2
(b)(2) to determine whether these data must be submitted. Section
II-A of this subdivision contains an additional discussion of the
"Formulators* Exemption" and who must submit the required data as a
general rule.
(2) The Agency will evaluate the following information pro-
vided by the registration applicant to make an assessment of what
constitutes-a significant inhalation exposure to workers:
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72
(i) Vapor pressure at 25"C and water solubility of the pes-
ticide active ingredient {§§63-9 and 63-8 of Subdivision D);
(ii) Soil adsorption coefficient (K
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73
inhalation exposure to workers. Applicants may omit the laboratory
studies and perform a greenhouse and/or field study instead. (See
§ 163-3.)
(i) Laboratory experimental conditions should represent, to
the extent possible, an environment where the pesticide is intended
for use. . . . .
(ii) The rate of test-substance application to soil should
approximate the intended rate of field usage*
(iii) The following factors should be addressed in designing a
laboratory volatility studys
(A) Properties of the pesticide such as vapor pressure, and
water solubility, which can influence the trapping medium and air
sampling ratesi
(B) Properties relating to the soil, such as adsorption to
soil and soil texture, to avoid untoward reduction of the rate of
volatility (e.g., sandy soil is preferred)?
(C5 Environmental factors, such as air temperature, humidity,
and movement, to avoid untoward dehydration or flooding of the
soil, and to assure efficiency of sampling.
(iv) Air samples should be collected and analyzed for residues
in the laboratory experimental equipment used. Monitoring should
be conducted continuously or at intervals which increase with time
after the start of the experiment. Monitoring should continue until
the nature of the residue decline curve has been clearly established.
(d) Reporting and evaluation of data. In addition to the
basic reporting requirements specified in f 160-5, the test report
should include the following specific information:
(1) Volatility data expressed as ug/cm2/hourj
(2) Air concentrations expressed as ug/m^ or mg/m3?
(3) Vapor pressure expressed as torr (or the equivalent ex-
pressed in other conventional units)?
(4) Temperature and relative humidity;
(5) A description of the soil usedj and
(6) A description of the laboratory test equipment used.
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"74
(e) References. (15 The following references contain
laboratory studies of pesticide volatility; information in these
papers could be useful for protocol development:
(i) Kearney, P.C., and A. Kontson. 1976. A simple system
to simultaneously measure volatilization and metabolism of pesticides
from soils. J. Agr. Food Chem. 24:424-426. [A polyurethane foam
trap and a potassium hydroxide trap were used to recover sequentially
the parent compound and degradation product from air.]
(ii) Spencer, W.F. and M.M. Claith* 1974. Factors affecting
vapor loss of trifluralin from soil. J.Agr. Food Chem. 22:987-991.
[The laboratory methods used for determining volatilization of
chemicals used in this study allow measurement of effects of several
variables. The use of hexane as a trapping medium limits the gas
flow rates and volumes that can be used.]
(iii) Spencer, W.F., T.D. Shoup, M.M. Cliath, W.J. Farmer, and
R. Haque. 1979. Vapor pressure and relative volatility of ethyl
and methyl parathion. J. Agr. Food Chem. 27:273-278. [Polyurethane
foam traps and GLC detection largely specific for the compounds of
interest were used here. Specific detection avoids interference that
may cause falsely high vapor levels in field testing.]
(2) Volatilization studies require methods for the trapping,
extraction, cleanup, and quantitation of pesticides. A review of
reported methods for laboratory investigations of pesticides in
air can be found in: :•••'••••.•.. , •
(i) Lewis, R.:G«: 1976. Sampling and Analysis of Airborne-...
Pesticides. Pp. 51-94 in Air Pollution frdm Pesticides and Agri-
cultural Processes. R.B. Lee (ed.). CSC Press, Inc. Cleveland,
Ohio. ''-.''• • - : - ' . ....-..;.
(ii) [Reserved]
§ 163-3 Field volatility studies.
(a) Purpose. Volatilization can be a major mode for the move-
ment of pesticides from treated areas. The vapors resulting from
volatilization of some pesticides can cause adverse effects to man
via inhalation exposure at sites of application or biological
effects in nontarget organisms at some distance from the treated
site. The Agency is particularly concerned about commercial green-
house applications involving intensive use of volatile pesticides,
use patterns which are characteristically involved with commodities
having high economic value and high labor requirements; such uses
can result in significant inhalation exposure to workers and appli-
cators.
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75
(b.) Hhen required. Data from a volatility study conducted
on-site in a commercial greenhouse and/or in the field will be
required by 40 CFR § 158 on a case-by-case basis only for those
pesticides that the Agency considers pose a potentially significant
inhalation exposure to workers [see § 163-2(b)] and, based on the
results of the laboratory study described in § 163-2, that also
demonstrate, in the opinion of the Agency, a significant rate of
volatilization from soil. See, specifically, 40 CFR § 158.50 and
§158.130 to determine whether these data must be submitted. Section
II-A of this Subdivision contains an additional discussion of the
"Formulators1 Exemption" and who must submit the required data as a
general rule.
(c) Test standards. Field volatility data submitted in res-
ponse to 40 CFR § 158.130 should be derived from tests which comply
with the general test standards in § 160—4 and all of the following
specific test standards:
(1) Test substance. The test substance shall be a typical
end-use product.
(i) If the applicant's product is an end-use product, the
test substance shall 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
that legally could'be used to make an end-use product- for which
volatility data are required, the test substance shall be a product
representative of the major formulation category which includes
that end-use product. (If the end-use products that could be made
from the manufacturing-use product belong to two or more major
formulation categories, a separate study must be performed for
each such category.) '
.(2) Test procedures. (i) The test substance should be ap-
plied to a site which is typical of one of the sites to which the
product would be applied.
(ii) The test substance should be applied to soil at the rate
and by the method stated in the label directions for the pesticide.
(iii) The following factors should be addressed in designing a
greenhouse or field volatility study:
(A) Properties of the pesticide such as vapor pressure and
water solubility, which can influence the trapping medium and air
sampling rates?
(B) Properties relating to the soil, such as adsorption to
soil and soil texture, to avoid untoward reduction of the rate of
volatility (e.g., sandy soil is preferred); :
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76
(C) Environmental factors, such as air temperature, humidity,
and movement, to avoid untoward dehydration or flooding of the
soil, and to assure efficiency of sampling.
(iv) Air samples should be monitored for residues at treated
sites at intervals which increase with time after pesticide appli-
cation. For example, the following schedule of sampling times
might be appropriate for some situations! 0 and 12 hours, 1, 2, 4,
7, 14,' and 21 days. Sampling should be continued until the nature
of the dissipation curve has been clearly established.
(d) Reporting and evaluation ofdata. In addition to infor-
mation meeting the basic reporting requirements specified in
§ 160-5, the test report should include the following specific
information:
(1) Volatility data expressed as g/ha/dayi
(2) Air concentrations expressed as ug/m^ or ng/m^j
(3) Vapor pressure expressed as torr (or the equivalent
expressed in other conventional units}; and
<4) Meterologic conditions (temperature, relative humidity,
wind velocity and direction, and cloud cover) during the time of
the field study.
{«}- References.- (1), The following references contain sup-
plemental information for -developing a protocol to conduct field.
volatility., studies!. , • •
(i) Cliath, M.M., W.F. Spencer, W.J» Farmer, T.D. Shoup, and
R. Srover. 1980. Volatilization of S-ethyl N,N-dipropylthiocarba-
mate from water and wet soil during and after flood irrigation of
an.alfalfa field. J. Agr« Food Chem. 28:610-613. [This is a •
well-designed and well-executed field study of volatilization with
simultaneous study of other modes of dissipation of a pesticide.]
(ii) Harper, L.A., A.W. White, Jr., R.R. Bruce, A.W. Thomas,
and R.A. Leonard. 1976. Soil and microclimate effects on trifluralin
volatilization. J. Environ. Qual» 5:236-242. [Ethylene glycol vapor
traps and non-specific GLC quantitation were used in this study. The
influence of water in soil and thus rainfall during the study on
volatilization of a pesticide are illustrated as are effects of wind,
turbulence, and temperature.]
(iii) Parmele, L.H., E.R. Lemon, and &.W. Taylor. 1972.
Micrometeorological measurement of pesticide vapor flux from bare
soil and corn under field conditions. Water, Air, and Soil Pollut.
1:433-451. [This study used hexylene glycol.vapor traps and sampling
periods adjusted to compensate for decrease in pesticide vapor
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77
concentration during the study, Pesticide vapor flux from soil was
calculated and related to micrometeorological measurements.]
(iv) Soderquist, C.J., D.G. Crosby, K.W. Moilanen, J.N. Sexber,
and J.E. Woodrow. 1975. Occurrence of trifluralin and its photo-
products in air. J. Acpc.food Chem. 23i304-309. [Although this
study was concerned with photolysis of pesticides in air, there
are procedures in this paper for measurement of volatilization of
a pesticide from soil.]
(2) Volatilization studies require methods for the trapping,
extraction, cleanup, and quantitation of pesticides. A review of
reported methods for field investigations of pesticides in air can
be found in:
(i) Lewis, R.G. 1976. Sampling and Analysis of Airborne
Pesticides. Pp. 51-94 in Air Pollution from Pesticides and Agricul-
Itural Processes. M.l. Lee (ed.), CHC Press, Inc. Cleveland,
Ohio.
(ii) [Reserved]
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78
Series 164: DISSIPATION STUDIES
§ 164-1 Field dissipation studies for terrestrial uses.
(a) Purpose. The purpose of field dissipation studies for
pesticides with terrestrial uses is to determine the extent of
pesticide residue dissipation under actual use conditions. These
studies will generate data required for the evaluation of mobility,
degradation, and dissipation of residues, These studies are required
because pesticide dissipation may proceed at a different rate under
field conditions and therefore result in the formation of levels of
degradates differing from those observed in laboratory studies.
(b) When required. Data from a terrestrial field dissipation
study are required by 40 CFR § 158 to support the registration of
an end-use product intended for any terrestrial use (except green-
house use), and to support each application for registration of a
manufacturing-use product which may legally be used to make such
an end-use product. See, specifically, 40 CFR § 158.50 and § 158.130
to determine whether these data must be submitted. Section II-&
of this Subdivision contains an additional discussion of the
"Formulators' Exemption" and who must submit the requiired data
as a general rule.
to) Tgst st.an_dard3. Field dissipation data submitted in
response to 40 CFR 158.130 should be derived.from testing which
complies with the "general test standards in § 160-4. and all of .the
following specific test standards:
{1) •Testsubstance* The test substance shall be a typical
end—use product. . - . • • •
(i) If an applicant's product is an end-use product, the test
substance shall 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
that legally could be used to make an end-use product for which
terrestrial field dissipation data are required, the test substance
shall be-a product-representative of the major formulation category
which includes that enduse product. {If the manufacturing-use
product is usually formulated into end-use products comprising two
or more major formulation categories, a separate study must be
performed with a typical end-use product for each such category.)
(2) Test procedures. (i) Sites. Field dissipation studies
should be conducted in at least two different sites which are
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79
representative of the areas where the pesticide is expected to be
used. For restricted use patterns where only one typical area is
involved, data from two similar sites are needed. Studies at
additional locations may be needed if the product is intended
for a terrestrial crop use, and the sites of application vary
appreciably in climate, terrain, or other pertinent characteristics.
(ii) 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.
(iii) Soil sampling. Soil from the treated area should be
'sampled following treatment for the purpose of ascertaining the
extent of pesticide dissipation.
(A) Soil samples serving as test controls should be obtained
from the intended application sites immediately prior to application
of the test substance and, to the extent possible, from adjacent
untreated areas at intervals during the course of the study and at
the termination of the study.
(B) Sampling times should include pre-application, date of
application, and immediate post-application. In the case of multiple
applications, only immediate post-application samples (and not
preapplication and date of application samples) should be taken in
addition.
CC) Soil samples should be taken in increments, to a maximum
depth of 15 cm, provided: that the results of studies ,on pesticide
leaching indicate'that the test substance is not likely to- leach
into soil to a. depth greater than than 15 em? and • •
(D) If data on leaching indicate that the test substance is
likely to leach into soil to a depth greater than 15 cm^ or if the
pesticide is incorporated into soil, then samples should be taken to
a depth sufficient to define the extent of leaching.
(iv) 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 soil, or to
the time periods specified below, whichever comes first:
(A) Field and vegetable crop uses: 18 months;
(B) Orchard crop and pastureland uses: 12 monthsj
(C) Domestic outdoor, park, ornamental, and turf uses: four
months; and
(D) Rights-of-way, shelter belts, and related uses: two
months.
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80
(d) Reporting and evaluation of data. In addition to the
basic reporting requirements specified in § 160-5, the test report
should include the following specific information:
(1) Residue decline curves in the tested soil; and
(2) Field test data, including:
(i) Amount of rainfall and irrigation water (accumulated from
first application to each sampling)?
(ii) Water table;
(ill) Srade (slope)}
(iv) Soil and air temperature data;
(v) Techniques and times of planting and harvesting;
(vi) Application time and method?
(vii) Sampling times and techniques;
(viii) Dates and stages of crop and pest development?
(ix) Application-to-harvest (if applicable) and application-
to-sampling intervals for each treatment? and
(x) Depth, weight, or. volume of each sample taken for analysis*
(e5 .References. (1) -The-following references contain in-
formation that could be useful for development of a protocol for.
conducting field dissipation studies:
• • (i) Caro, J.H., H.P. Freeman, and B.C. Turner. 1974. Per-
sistence in soil and losses in runoff of soil-incorporated carbaryl
in a small watershed. J. Agr. Food Ghent. 22:860-863. [This is a
wellplanned and well-executed field dissipation study.]
/(ii) Miller, C.H.,.T.J. Monaco, and T.J. Sheets. 1976. Studies
on nitralin residues in soils. Weed Sci. 24:288-291. [The
experimental design and sampling procedures in this paper are well
devised.]
(iii) Polzin, W.J., I.F. Brown, Jr., J.A. Manthey, and G.W.
Probst. 1971. Soil persistence of fungicides - Experimental design,
sampling, chemical analysis, and statistical evaluation. Pest.
Monit. J_. 4:209215. [The factors causing variability in field
dissipation studies are considered and analyzed in this paper,
However, this study is more detailed than required for pesticide
registration.]
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.81 ..
'- '"•'. '•• '•• .- <-*, ^ ., " . - "* '
(iv) Smith, A.E., and A. Walker. 1977. A quantitative study
of asulam persistence in soil. Pestic. Sci. 8:449-456. [The
experimental design and statistical analyses of data in this paper
are described in detail for field dissipation studies.]
(2) The following reference contains supplemental information
fot developing a protocol for field dissipation studies:
(i) Goring, C.A.I., D.A. laskowski, J.w. Bamaker, and R.w. Meikle.
1979. Principles of Pesticide Degradation in Soil. Pp. 135-172 in
Environmental Dynamics of Pesticides. R. Haque and V.H. Freed
(eds.). Plenum Press. New York. [This is an excellent review for
analyses of data and for an understanding of factors affecting
persistence of pesticides in soil.]
(11) [Reserved.]
§ 164—2 Field dissipation studies for aquatic uses and aquatic
impact uses.
Purpose. The purpose of aquatic field dissipation studies
for pesticides for aquatic uses is to determine the extent of
dissipation and mobility of pesticide residues under actual use
conditions. 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 disap-
pearance of parent compound) and provide information with respect
to mechanisms of dissipation in various aquatic environments. An
aquatic field dissipation study is,also required because pesticide
dissipation may proceed at a different rate in the aquatic environ-
ment than in laboratory aquatic studies.
(b) When required. (1) Except as provided in § 164-2(b)(25,
data from an aquatic field dissipation study are required by 4,0 CFR
§ 158 to support the registration of an end-use product intended
for aquatic food crop uses, for 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 for any
aquatic impact uses involving direct discharge of treated water
into outdoor aquatic sites. Data from such a study are also required
to support each application for registration of a manufacturing-
use product which may legally be used to make such an end-use prod-
uct. See, specifically, 40 CFR § 158.50 and § 158.130 to deter-
mine whether these data must be submitted. Section II-A of this
Subdivision contains an additional discussion of the "Formula-tors"
Exemption" and who must submit the required data as a general
rule.
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82
(2) Pesticides intended for use as antifouling paints and for
similar related protective aquatic uses are exempt from the aquatic
field dissipation data requirements of 40 CFR § 158.130 if the
following conditions are met:
(i) The octanol/water partition coefficient of the product is
approximately 1000 or less; and
(ii) The half-life of the active ingredient in water is less
than four days as demonstrated by the hydrolysis studies, § 161-1.
(c) Combined testing. Testing conducted to fulfill this data
requirement may be combined with the testing conducted to meet the
requirements of § 165-4 < field accumulation studies in aquatic
nontarget organisms), provided that the test, standards for each
study are met.
(d) Test standards. aquatic field dissipation data submitted
in response to 40 CFR § 158.130 should be derived from testing which
complies with the general test standards in § 160-4, and all of the
following test standards:
(1) Test substance. The test substance shall be a typical end-
use product.
(i) If the applicant's product is an end-use product, the
test substance shall be a product whose formulation is typical
of the 'formulation category (e.g., wettable powder, emulsifiable . . •, • s,;
concentrate, granular product) to • which the product belongs.
(ii) If the applicant's product is a manufacturing-use pro- ' ,•:--•
duct that legally could be used to make an end-use product for
which aquatic field dissipation data are required, the test substance
shall 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 must 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, data from two similar sites are needed. Studies in
additional locations may be needed if the pesticide is intended for
an aquatic food crop use, and the sites of application vary in
climate, terrain, or other pertinent characteristics.
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83
(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 thfe 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 applica-
tion or from direct aquatic discharges immediately prior to appli-
cation 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. . • • • •
(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
(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
shall 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 eoines 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.
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84
(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 max!"".™ 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) Ifi5e~siaximum test duration for water sampling should be one
month following each discharge event.
(e) Reporting and evaluation of data. In addition to the
basic reporting requirements '-specified in § 160—5, the test • •'•'•;.:.--«-.
report should include the following specific information: , -•.••r&s.,
(1) Decline curves of residues in each major substrate analyzed?
and . ' "'•-''
(2) Field test data, including:
(i) Dates of planting and harvesting of crops, if applicable?
(ii) Application time(s) and method;
(iii) Sampling times and techniques?
(iv) Dates and stages of crop and pest development, if appli-
cable;
(v) Application-to-harvest (if applicable) and application—
to-sampling intervals for each treatment;
(vi) Depth, weight, or volume of each sample, and weights and
volumes of aliquots taken for analysis ? and
(vii) Flow data expressed in terms of volume or linear flow.
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85
(f) References» (1) The following references contain sup-
plemental information for developing a protocol for conducting
aquatic crop studies:
(i) Demint, R.J., J.C. Pringle, Jr., A. Battrup, V.F. Brims,
and P.A. Frank. 1975. Residues in crops irrigated with water
containing trichloroacetic acid. J_. Agr. Pood Chem. 23:81-84.
[This paper presents a procedure for assessment of pesticide carry-
over in irrigation water,]
(ii) Rice, C.P., B.C. Sikka, and R.S. Lynch. 1974. Persistence
of dichlobenil in a farm pond. J_. Agr. Food Chem. 22:533-534.
[This paper presents procedures for assessment of fate of a pesticide
in a water-sediment system.]
(iii) 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. 24s733-739. [This
paper contains a small-scale technique for assessment of the fate
of a pesticide in a water-sediment ecosystem.]
(2) The following references contain supplemental information for
developing a protocol for conducting aquatic non—crop studies:
(i) Rice, C.P., B.C. Sikka, and R.S. Lynch. 1974. Per-
sistence of dichlobenil in a farm pond. J» Agr. Food Chem. 22:533-
534. [This paper contains a procedure for assessment of fate of a
pesticide in •«. watersediment .system. Information on background
interference :and pesticide recovery.from soil and water are presented.]
. - • (ii) 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. Ajr. Food Chem. 24i733-739. [This
paper contains a -small-scale technique for assessment of fate of
a pesticide.]
§ 164-3 Dissipation studies for forestry uses.
(a) Purpose. Data from a residue dissipation study, conducted
under actual use conditions, will indicate the extent and rate of
pesticide residue dissipation and mobility in both aquatic and
terrestrial environments which are encompassed in forestry sites.
(b) When required. Data from a field dissipation study for
forestry uses are required by 40 CFR § 158 to support the registra-
tion of an end-use product intended for forestry use, and by each
applicant for registration of a manufacturing-use product which may
legally be used to make such an end-use product. See, specifically,
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40 CFR § 158.50 and § 158.130 to determine whether these data must be
submitted. Section II-A of this subdivision contains an additional
discussion of the "Formulators1 Exemption" and who must submit the
required data as a general rule.
(c) Combined testing. Testing conducted to fill this data
retirement may be combined with testing conducted in accordance
with § 165-5 (field accumulation studies in aquatic nontarget
organisms), provided that the test standards for each study are
met.
(d) Test standards. Forestry dissipation data submitted in
response to 40 CFR § 158.130 should be derived from testing which
complies with the general test standards in § 160-4 and all of the
following specific test standards:
(1) Test substance. "The test substance shall be a typical
end-use product.
(i3 If the applicant's product is an end-use product, the
test substance shall 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
that legally could be used to make an end-use product intended for
forestry use, the test substance shall be a product representative
of the major formulation category which includes that end-use
product. [If the manufacturing-use product is usually formulated
•into end-use products comprising two or more major formulation
categories, a separate.study must be performed with a typical
end-use product for each such -category.] • ' ' . '
(2) Test procedures, (i) Sites. A dissipation study should
be conducted in at least one location representative of the areas
in which the pesticide product would usually be used. Studies at
additional sites may be necessary if the product is intended for
use in forest sites with substantially differing characteristics.
(ii) 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
label.
(iii) Environmental components. The level of pesticide
residues shall be measured in the following items:
(A) Foliage (if the pesticide is foliar-applied);
(B) Leaf litter;
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(C) Soil under leaf litter;
(0) Exposed soil;
(K) Standing (pond) water;
(F) Moving (stream) water; and
(G) Sediments from both ponds and streams*
(iv) Controls . Test control samples of the environmental
components described in paragraph (d)(2)(iii) of this section
should be obtained from the intended sites of application imme-
diately prior to application of the test substance and, to the
extent possible, from adjacent untreated areas at intervals during
the course of the study and at the termination of the study.
(v) sampling intervals* (&) For exposed soil, soil under
leaf litter, and foliage, sampling times should include, at a minimum,
preapplication (control), date of application, and three samplings
within the first week post application for each single or multiple
application of the test substance.
(B) For sediments , standing (pond) water, and moving (stream)
water, sampling should include, at a minimum, pre-application (control),
date of application, and immediately post- application for each
single or multiple application of the test substance.
(v) 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
sampled or the maximum times specified below, whichever comes first:
12 months after the last application for soil and leaf litter, 6
months after the last application for ^sediment, and. !• month after the.
last application for water (pond and stream).
(vi) Dissipation curves. Decline curves shall be constructed
for residues in leaf litter, soil, foliage, and standing water.
Reporting- and evaluation of data. In addition to" the basic.
reporting requirements specified in § 160-5, the test report should
include the following specific information:
(1) Decline curves of residues in each major substrate
analyzed; and
(2) Field test data, including:
• (i) Precipitation (accumulated from first application to each
sampling) j
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(ii) Water table;
(iii) Grade (slope); •
(iv) Application tine?
(v) Sampling time?
(vi) Dates and stages of pest development;
(vii) Application-to-sampling intervals for each treatment;
(viii) Depth, weight, or volume of each sample, and weights
and volumes of aliquots taken for analysis; and
(ix) When water flow is measured, flow data expressed in
terms of volume or linear flow.
(f) References, The following references contain supplemental
information for developing a protocol for conducting forest field
dissipation studies:
(1) Symons, P.E.K. 1977. Dispersal and toxicology of the
insecticide fenitrothion? predicting hazards of forest spraying.
Residue Rev. 68s1—31. [This review provides general information
and an overview of problems that have occurred in a forest environ-
ment in association with use of an insecticide for control of a
forest pest. Pesticide residues in organisms and physical environment,
and dissipation of the residues are discussed.]
• - (2) Roberts, J.R», fireenhalgh, R», and Marshall, W.K«, eds.
1977. Proceedings of a Symposium-on Feni'trothion: The Long-term
Effects of its 0se in Forest Ecosystems* . (Natl«,Bes« -Council Can.$
Ottawa," Canada) HRCC/CNRC No. 16073:573-614. '[Individual papers within
these proceedings contain protocols for the study of pesticide
dissipation in a forest ecosystem.]
(3) Giles, R.H., Jr. 1970. The Ecology of a Small Forested
Watershed Treated with the Insecticide Malathion-S 35. wildlife
Monographs. No. 24. The Wildlife Society. Washington, D.C. [This
paper contains experimental procedures for conducting terrestrial/aquatic
'(forest) dissipation studies. Studies contained in the reference
are more extensive than generally required.]
(4) Maguire, R.J. and E.J. Hale. 1980. Fenitrothion sprayed
on a pond: kinetics of its distribution and transformation in water
and sediment. £. Agr. Food Chem. 28:372-378. [This paper contains
protocols 'for the study of dissipation of a pesticide from a pond
within a forest and from segments within that environment.]
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(5) Peiper, G.R. 1979, Residue analysis of carbaryl on
forest foliage and in stream water using HPLC. :Bull_. Environ»
Contam. Toxicol» 22:167-171. [This paper contains studies of
residue concentrations and dissipation of those residues from plant
surfaces and from forest streams after serial pesticide application.]
(6) SzetOf S.Y., H.R. MacCarthy, P.C. Oloffs and R.F. Shepherd,
1978. Residues in Douglas-fir needles and forest litter following
an aerial application of acephate (Orthene). J. Inviron. Sci.
Health (B) 13s87-1Q3. [This paper contains protocols for the study
of distribution, transformation, and dissipation of a pesticide
within a forest canopy after aerial application.]
| 164-4 Dissipation studies for combination products and tank mix
uses*
(a) Purpose. The objective of this study is to determine the
dissipation characteristics of a pesticide in soil when applied as
a tank mix or in combination with other pesticides, whether in a
combination product or pursuant to labeling directions recommending
the simultaneous or serial application of two or more products.
The Agency requires these data to ascertain if overall soil
persistence of pesticides is affected by the simultaneous or serial
application of two or more pesticides.
(b) When required. A laboratory or field soil dissipation
study is required by 40 CFR § 158 on a case-by-case basis to support
the registration of an end-use product containing more than one
active ingredient intended for use as a component in tank mixtures,
or customarily applied serially with another pesticide product.
See, specifically, 40 CPR § 158.50 and } 158.130 to determine
whether these data must be submitted. Section II-A of;this subdi-
vision contains an additional discussion of the "Formulators1
Exemption" and who must submit the required data as a general rule,
^c) Test standards. The dissipation studies described in
paragraph of this section should be derived from testing which com-
plies with the general test standards in § 160-4 and all of the
following specific test standards:
(1) Test substance. (i) For studies on combination products,
if the end-use product contains two or more active ingredients
(combination product), the test substances shall be the end-use
product and similarly formulated products containing each active
ingredient singly.
(ii) For studies on tank mixtures, if the use directions
state that two or more end-use products containing different active
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ingredients may be applied as a tank mixture, the test substances
shall be the mixture of the end—use products prepared in accordance
with the label directions, and each separate end-use product.
(iii) For studies on serial applications, if the use directions
state that two or more end-use products containing different active
ingredients may be applied serially, the test substances shall
consist of the two or more end—use products to be used in the
sequence specified in the label directions*
(2) Test procedures, (i) Application. ISie test substance(s)
should be applied at the highest rate recommended by product labeling
and as follows:
(A) For combination products, apply the test substances at
the label-recommended field application rates to both light- and
heavy-textured soils. Incorporate the test substances into the
soil if recommended by label directions*
(B) For tank-mixed pesticides, apply the test substances at
the label-recommended field application rates to both light- and
heavy-textured soils. Incorporate each test substance into the
soil if recommended by label directions.
(C) For serially-applied pesticides, apply the test substances
individually and as the sequential combination at the label-
recommended field application rates to both light- and heavy-textured
soils. Incorporate each test substance into the soil if recommended
by label directions.
(ii) Soil sampling. .Soil from the treated' area or laboratory
container should be sampled following treatment for the .purpose of
ascertaining the extent of pesticide dissipation*
(A) Soil samples obtained from the intended site(s) of
application or from the laboratory containers immediately prior to
application of the test substance should be used as experimental
controls.
(B) Sampling times should include pre-application, date of
application, and immediate post-application. In the case of multiple
applications, only immediate post-application samples (and not
preapplication and date of application samples) are to be taken in
addition.,
(C) Soil samples should be taken in increments to a depth of
15 cm, unless results of studies on pesticide mobility indicate
that the test substance is likely to leach into soil deeper than 15
cm*
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(D) If data on leaching indicate that the test substance is
likely to leach into soil deeper than 15 cm, or if the pesticide is
incorporated into soil deeper than 5 cm* samples should be taken to
a depth sufficient to include most of the leached pesticide.
(iii) 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 soil, or for
a maximum duration of six months, whichever occurs sooner.
(d) Reporting and evaluationof data. In addition to the
basic reporting requirements specified in § 160-5, the applicable
reporting requirements as specified in | 164-i-Kd) apply.
(e) References. The following references contain supplemental
information for developing a protocol to conduct a combination or
tank mix study:
(i) Kaufman, D.D., J. Blake, and D.E. Miller. 1971.
Methylcarbamates affect acylanilide herbicide residues in soil. J.
Agr. Food Chem. 19:204-206. {This paper provides techniques to
assess a complex pesticide degradation problem.]
(ii) Kaufman, D.D., P.C. Kearney, D.W. Von Endt, and D.E.
Miller. 1970. Methylcarbamate inhibition of phenylcarbamate
metabolism in soil. J. Agr. Food Chem. 18s513-519. [This precursor
of the 1971 paper (above) contains procedures that may be useful
for ^the design, .of experimental studies required on combination and
tank mixes.]' .
§ 164-5 Long-term soil dissipation studies.
^a^ Purpose. The objective of this study is to enable the
Agency to assess the fate of pesticide residues that do not readily
dissipate in the soil environment. Slow pesticide dissipation in
soil may increase the residue burden imposed by pesticides by
increasing their residence time in the environment.
(b) When required. (1) Data from a. long-term soil dissipation
study are required by 40 CFR § 158 to support the registration of
any end-use product:
(i) If it contains an active ingredient with residues that do
not reach 50 percent dissipation in soil prior to recommended
subsequent application of that same active ingredient to the same
sites utilized for the field dissipation study described for field
and vegetable crops in § 164-1 and for aquatic food crops in § 164-
2(b)(l); or
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(ii) If the aerobic soil metabolism study described in | 162-
1 demonstrates that, for field and vegetable crop uses and aquatic
food crop uses, the total of pesticide (excluding bound) residues
in soil are greater than fifty percent of the amount of pesticide
initially applied at the time when a subsequent application would
occur.
(2) Data from a long-term soil dissipation study are also
required to support each application for registra-tion of a
manufacturing-use product that legally could be used to make an end-
use product meeting the criteria of paragraphs (b)(1) (i) or (ii) of
this section. See, specifically, 40 CFR § 158^50 and § 158. 130 to
determine whether these data must be submitted. Section II-A of
this Subdivision contains an additional discussion of the "Formulators*
Exemption* and who must submit the required data as a general rule.
(c) Test standards • long-term soil dissipation data submitted
in response to 40 CFR § 158.130 should be derived from testing which
complies with the general test standards iii § 160-4 and all of the
following test standards ':•
(1) Test substance. The test substance shall be a typical
enduse product.
(i) If the applicant's product is an end-use product, the
test substance shall be a product with a formulation 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 "
that legally could be used to make an end-use ' product for which
longterm soil dissipation data are required, the test substance
shall be a product representative of the major .formulation category
which includes that end— use product. [If the manufacturing— use
product is usually formulated into end-use products' comprising two
or more major formulation categories, a separate study must be
performed with a typical end-use product for each such category.]
(2) Test procedures. The applicant should follow .the' test
procedure applicable to the use pattern or patterns of the product:
Field and vegetable crop uses. (A) The test substance
should be applied using the method and highest rate of application
stated in the directions for use specified in the product label.
(B) Soil sampling (methods and scheduling) should be performed
in accordance with the standards set forth in § 164-1 (c) (2) (iii) .
(C) Total duration of this study need not exceed three years
or extend two years beyond the length of the terrestrial field
dissipation study for field and vegetable crop uses .
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(ii) Aquatic food crop uses. (A)' The test substance should
be applied using the method and highest rate of application stated
in the directions for use specified on the product label.
(B) Soil sampling (method and scheduling) shall be performed
in accordance with the standards set forth in § 164-2(d)(45«
(C) Total duration of this study need not exceed three years
or extend two years beyond the length of the aquatic field dissipation
study for aquatic food crop uses.
(d) Reporting and evaluation of data. In addition to the
applicable reporting requirements specified in § 160-5, the specific
reporting requirements described in § 164-l(d) apply for studies
involving field and vegetable crop usesf and. those in 164-2(e)
apply for studies involving aquatic food crop uses.
(e) References. The following references contain supplemental
information for developing a protocol to conduct a long—term soil
dissipation study:
(1) Burnside, O.C. 1974. Trifluralin dissipation in soil
following repeated annual applications. Weed Sci. 22;374-377.
[This paper reports a long—term pesticide dissipation study with
repeated applications at different levels of treatment and with
replication. Assessment of residue levels was accomplished by
bioassays- with several crops and by a chemical analysis of soil
extracts. The/use• of -this. bioassay technique can indicate the
quantity of active, herbicide remaining, but the technique is
limited to- herbicides. A chemical pesticide residue analysis is
more generally applicable.] .
(2) Caro, J.H., H.P. Freeman, and B.C.'Turner. 1974. Persis-
tence in soil and losses in runoff of soil-incorporated carbaryl
in a small watershed. £. Agr. Food Chem. 22:860-863. [This paper
is recommended as a model for the design of a long-term study
protocol. The use of- a field standard applied with the subject
pesticide might aid in interpretation of dissipation kinetics.]
(3) Demint, R.J., J.C. Pringle, Jr., A. .Hattrup, V.F. Burns,
and P.A. Frank. 1975, Residues in crops irrigated with water
containing trichloroacetic acid. J_. Agr. Food Chen. 23:81-84.
[The methods described here may be useful in designing protocols
for long-term study of pesticides applied in irrigation water.]
.(4) Miller, C.H., T.J. Monaco, and T.J. Sheets. 1976.
Studies on nitralin residues in soils. Weed Sci. 24:286-291.
[This study evaluated the effect of residue build-up from
repeated application of three levels of nitralin to soils. Both
biological and chemical assays were used with a sensitive crop for
the'bioassay. Combination of the two assays may in some.cases.'aid
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in interpretation of data. The use of plastic for storing samples
should be avoided to prevent possible interferences from desorbed
plastic components or loss of residues by sorption to the plastic.]
(5) Polzin, W.iJ», I.F. Brown, Jr., J.A. Manthey, and G.W.
Probst. 1971, Soil persistence of fungicides - Experimental design,
sampling, chemical analysis and statistical evaluation, Pest.
Monit.J. 4:209215. [This paper was not intended as a long-term
study, but rather was a study to improve the reliability of soil
persistence data. It is cited here as a guide for improving soil
sampling protocols.]
(6) Rice, C.P., H.C. Sikka, and R.S. Lynch. 1974. Persis-
tence of dichlobenil in a farm pond. J. Agr. Food Chem. 22:533-534.
[This paper reports dissipation of pesticide from water and the
associated sediment in a pond. The use of blanks and fortified
samples to evaluate recovery of pesticide from substrates and
interference to quantitation as was done in this paper are good
practice.]
(7) 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. [Several
of the phenomena observed in this paper are worth considering.
Dissolution of pesticide formulation can be the rate*limiting step
in a pesticide dissipation, and the whole system must be sampled,
including strata, to give an accurate material balance. The
evaluation of'pesticide•stability in samples Is recommended espe-
cially if-there will be delay between • sampling and analysis."]"' '"•*;;•/•
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Series 165s ACCUMULATION STUDIES
§ 165-1 Confined accumulation studies on rotational crops*
(a) Purpose. Data from confined (laboratory/greenhouse/out-
door small plot) accumulation studies on rotational crops will
enable the Agency to determine the nature and amount of pesticide
residue uptake in rotational crops. Such data are used to establish
realistic crop rotation restrictions (time from application to a
time when crops can be rotated) or to provide information for
determining if tolerances are needed in rotational crops.
(b) When required. Data from a confined accumulation study
on rotational crops are required by 40 CFR § 158 to support the
registration of an end—use product intended for field-vegetable
crop use, aquatic crop use, or use on any other site on which it is
reasonably foreseeable that any food or feed crop may be produced
after application of a pesticide. Such data are also required to
support each application for registration of a manufacturing-use
product which legally could be used to make such an end-use product.
See, specifically, 40 CFR § 158.50 and § 158.130 to determine whether
these data must be submitted. Section II-A of this Subdivision
contains an additional discussion of the "Formulators1'; Exemption"
and who must submit the required data as.a general rule.
(c). Test standards• Rotational crop accumulatipn data submitted
in response to 40 CFR § 158.130 should be derived froia testing which
complies with the general test standards in § 160-4 and all of the
following.specific test standards:
(1.) Test substance. This study shall be conducted using the
radioactively-labeled analytical grade of the active ingredient.
(2) Test procedures. (i3 This study should be performed
using a sandy loam Soil which has been treated with the test
substance applied at a rate equivalent to that expected under actual
field use conditions. However, if the label instructions of the
product limit its use to one soil type other than the sandy loam,
then the study should be run with the soil type specified on the
label.
(ii) Following soil treatment, the pesticide should be aged
under aerobic conditions in the soil for a time approximating the
anticipated agricultural practice (e.g., 1 year for crops rotated
the following year, 120 days for crops rotated immediately after
•harvest, and 30 days for assessing circumstances of crop failure).
Growing the treated crop in the soil during the aging period is not
precluded.
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(iii) Crops planted in the treated and aged soil should include
those expected in the proposed rotational schedule and, where pos-
sible, be representative of each of the following crop groupings:
root (e.g., beets, carrots)? small grain (e.g., wheat, barley),
and leafy vegetable (e.g., spinach, lettuce). The selected crops
shall be analyzed for residues at appropriate harvest intervals*
(Residue analyses should be performed on selected crops at multiple
intervals if both immature and mature crops are normally harvested
in the course of usual agricultural practices.)
(iv) Residues in the soil should be analyzed at the time of
treatment, at the time of planting of the rotational crop, and at
the time of harvest of the rotational crop. However, if this
confined accumulation study is carried in the same soil and at the
same time as the aerobic soil metabolism study (§162—1) or the
terrestrial field dissipation study (§164-1), then the soil residue
analyses from these studies will suffice. See also f160-4(e) of this
Subdivision.
(d) Reporting and evaluation of data. In addition to the
applicable reporting requirements specified in § 160-5, the following
data should be reported:
(1) The registration applicant should characterize and, when
feasible, identify and provide analytical values for significant
residues in the crops tested. Significant residues include parent
compound, closely-related degradates, metabolites and/or their
conjugates in. the crop, but do not include C14 activity in the
crop associated with that being incorporated into the carbon pool
and ultimately into natural plant constituents. 'In cases where
identification of residues is not feasible due to' insufficient
sample, then pooling of samples obtained from replicate experiments
conducted simultaneously should be carried out to enable residue
identification to be achieved. From the results of this study, the
Agency will determine whether additional studies to measure the
accumulation of pesticide residues in rotated crops under actual
field conditions are needed. If such field studies are needed,
the registration applicant will need to determine whether to conduct
the field study described in § 165-2 of this Subdivision or to carry
out residue uptake studies described in Subdivisic-n O (Residue
Chemistry Data Requirements) necessary to support' the establishment
of a tolerance in the rotated crop. (See also FR 46(83, 3016,
January 13, 1981.)
(2) Depending on the crop tested, separate analyses should
be conducted on different portions of the plant. For example,
both the aerial and root portions of root crops should be analyzed.
(3) Analyses, including a description of data variability,
for residues of parent compound and degradates in soil for each
sampling interval.
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(4) A description of the growing conditions should be reported.
If the study is conducted outdoors, rainfall data, temperature
monitoring data, and general climatic conditions should be reported
for the test period.
(e) References. The following references contain information
for developing a protocol for study of the uptake of residues in
rotational crops:
(1) Burnside, O.C. 1974. Trifluralin dissipation in soil
following repeated annual applications. Weed Sci. 22:374-377.
[The general methods used by this author could be adapted to small-
scale field studies. The techniques used in this study should be
considered for development of a protocol to obtain data on pesticide
uptake with rotational crops.]
(2) Burnside, O.C., C.R. Fenster, and G.A. Wicks. 1971.
Soil persistence of repeated annual applications of atrazine. Weed
Sci. 19: 290-293. [This paper contains procedures for investigation
of pesticide fate with different soils and cropping practices»J
(3) Sirons, G.J., R. Frank, and T. Sawyer. 1973. Residues
of atrazine, cyanazine, and their phytotoxic metabolites in a clay
loam soil. J_* Agr. fdc>a~Chem, 21:1016-1020. [This is not a study
of uptake of a pesticide in a rotational crop system, but the
procedures used could be applicable to design such a study. The study
of a phytotoxic metabolite is included in this study.]
(4.) -Bull,-D.L., and G.W. Ivie,'1982. Fate of 0-[4-[{4-
chlorophenyl)thio]phenyl] O-ethyl S-propyl phosphorothioate (RH-
0994} in soil. J.' AGR. Food Chem 3£; 150-155. [This paper is a
good example of procedures for a combined soil metabolism and
rotational- crop uptake study. The- paper differs from the require-
ments of § 165-1 in that the 14C residues in the rotated crops
were not characterized.] •
§ 165-2 Field accumulation studies on rotational crops.
(a) Purpose. Data from field accumulation studies on rota-
tional crops will enable the Agency to determine under actual
field-use conditions the nature and amount of pesticide residue
uptake in rotational crops. Such data are used to establish rea-
listic crop rotation restrictions (time from application- to a time
when crops can be rotated) and to provide information for determining
if tolerances are needed in rotational crops.
(b) When required. Data from a field accumulation study to
determine the uptake of soil residues by rotational crops are
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required by 40 CFR § 158 to support the registration of an end-use
product, and to support each application for for registration of
a manufacturing-use product used to make such an end-use product,
only under the following circumstances:
(1) When significant C^1* pesticide residues of concern to the
Agency are detected in the test crops analyzed in the confined
accumulation study, § 165-1[See § 165-1(d){1) for a discussion of
significant residues]; or
(2) When a subsequent crop is treated with the same active
ingredient as the initial crop.
(3) Seer specifically, 40 CFR § 158.50 and § 158.130 to
'determine whether these data must be submitted. Section II-A
of "this Subdivision contains an additional discussion of the
*Formulators" Exemption" and who must submit the required data
as a general rule.
(c) Test standards. Field accumulation data submitted in
response to 40 CFR § 158.130 should be derived from testing which
complies with the general test standards in § 160-4 and all of the
following test standards:
(1) Test substance. The test substance shall be a typical
end-use product.
(i) If the applicant's product is an end-use product, the
test substance shall 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
that legally could be used to make an end-use product for which
rotational crop accumulation data are required, the test substance
shall be a product representative of the major formulation category
which includes that end-use product. (If the manufacturing-use
product is usually formulated into end-use products comprising two
or more major formulation categories, a separate study must be
performed with a typical end-use product for each such category.)
(2) Test 'procedure. (i) Sites. Field accumulation studies
should be conducted in at least two different sites which are repre-
sentative of the areas where rotated crops are expected to be
grown. The soil type at one of the test sites should be the same as
that used in the confined accumulation study of § 165-1. For
restricted use patterns where only one typical area is involved,
data from two similar sites should be submitted. See, specifically,
40 CFR § 158.50 and § 158.130 to determine whether these data must
be submitted. Section II-A of this Subdivision contains an addi-
tional discussion of the "Formulators1 Exemption™ and who must
submit the required data as a general rule.
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(ii) Application. (A) The soil at the test site should be
treated with the test substance applied by the method stated in
the directions for use specified on the product label and at the
highest recommended label rate*
(B) Following soil treatment, the pesticide should be aged
under aerobic conditions in the soil for a time approximating the
anticipated agricultural practice (e.g., one year for crops rotated
the following year, 120 days for crops rotated Immediately after
harvest, and 30 days for assessing circumstances of crop failure).
Growing the treated crop in the soil during the aging period is
not precluded.
(iii) Sampling. (A) Representative root, small grain, and
leafy vegetable crops typical of the area where the product is to
be applied should be planted as rotational crops.
(B) If the registration applicant is proposing a tolerance
for residues in a rotated crop, then that crop should be planted,
harvested, and analyzed for residues at test sites selected in
accordance with the requirements of 40 CFR § 158.125, described
in detail in Subdivision o (Residue Chemistry Data Requirements).
(C) The rotational crops should be analyzed for residues at
appropriate harvest times. (Residue analyses should be performed
on selected crops at multiple intervals if both immature and mature
crops are normally harvested in the course of usual agricultural
practices.) ' .
1 (D) Residues in the soil should be analyzed at times of treat-
ment, at time of planting rotational crops, and at the time of
rotational crop harvest. These soil analyses may not be needed if
the aerobic soil metabolism study {§ 162-1) or the terrestrial
field dissipation study {§ 164-1) provide soil residue data that
demonstrate essentially complete dissipation of the pesticide by
the time the original crop is harvested. (In some cases, this
study can be combined with the aerobic soil metabolism study and
the terrestrial field dissipation study.)
(iv) Test duration. Residue data should be collected in soil
and rotational crops until the time that the rotational crop is
normally harvested.
Jd) Reporting and evaluation of data. ' In addition to the
applicable reporting requirements specified in § 160-5, the follow-
ing data should be reported;
(1) Field test data including:
(i) Dates of planting and harvesting;
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(ii) Amount of rainfall and irrigation water (accumulated
from application to harvest); " . . .
(iii) Depth of Crater table?
{iv) Slope of test site(s);
(v) Temperature monitoring data and a description of the
general climatic conditions at the test site during the study?
(vi) Techniques and times of planting, culture, and harvesting;
(vii) Application time and method;
(viii) Sampling times and techniques;
(ix) Stages of crop development at times of sampling;
(x) Application-to-harvest interval; and
(xi) Depth, weight, or volume of each sample taken for analysis,
(2) Analysis for residues of parent compound and degradates
in the crops« Depending on the crop, separate analyses should
be conducted on different portions of the plant* For example,
analysis of both the aerial and root portions of root crops should
be conducted*
(3) Analyses for residues of parent compound and degradates
in soil for each sampling interval. '
(4) .A description of residue data variability in soil and
rotational crops.
(e) ' References. 'The following references contain information
for developing a protocol for study of the uptake of residues in
rotational crops:
(1) Burnside, O.C. 1974. Trifluralin dissipation in soil
following repeated annual applications. Weed Sci. 22s374-377.
[The general methods used by this author could be adapted to small-
scale field studies. The techniques used in this study should be
considered for'development of a protocol to obtain data on pesticide
uptake with rotational crops.]
(2) Burnside, O.C., C.R. Fenster, and G.A. Wicks. 1971.
Soil persistence of repeated annual applications of atrazine. Weed
Sci. 19:290-293. [This paper contains procedures for investigation
of pesticide fate with different soils and cropping practices.]
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(3) Sirons, G.J., R« Frank, and T. Sawyer. 1973. Residues
of atrazine, cyanazine, and their phytotoxic metabolites in a clay
loam soil. £. Agr. Food Chem. 21:1016-1020. [This is not a study
of uptake of a pesticide in a rotational crop system, but the
procedures used could be applicable to design such a study. The
study of a phytotoxic metabolite is included in this study.]
(4) [Reserved]
§ 165-3 Accumulation studies on irrigated crops.
(a) Purpose. The purpose of these studies is to determine
residue uptake and levels in representative crops which are expected
to be irrigated with water from a field treated with a pesticide
(e.g., reclaimed waste water or water from a rice field used to
irrigate upland crops). Such studies are needed to establish realistic
label restrictions to prevent residues in irrigated crops and/or to
provide information for a determination as to whether tolerances
may be needed in the irrigated crop.
(b) When required. Data from a study of residue accumulation
in irrigated crops under actual field use conditions are required
by 40 CFR § 158 to support the registration of an end-use product
intended for aquatic food crop or aquatic non-crop uses, for uses
in and around-.holding ponds used for irrigation purposes, or for
uses involving effluents or discharges to water used"for crop
"irrigation. Data from such a study are also required to support each
application for•• registration .of a manufacturing—use product which
legally could be used to make such an end-use product. See,
specifically, 40 CFR § 158.50 and § 158.130 to determine whether these
data must be submitted* Section II-A of this Subdivision contains
an additional discussion of the "Formulators1 Exemption" and who must
submit the required data as a general rule.
(c) Test standards. Irrigated crop accumulation data submitted
in response to 40 CFR § 158.130 should be derived from testing which
complies with the general test standards in § 160-4 and all of the
following specific test standards:
(1) Test substance. The test substance shall be a typical
end—use product.
(i) If the applicant's product is an end-use product, the
test substance shall be a product whose formulation is typical o.f
the formulation category (e.g., wettable powder, emulsifiable
concentrate, granular product} to which the product belongs.
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(ii) If the applicant's product is a manufacturing-use product
that legally could be used to make an end-use product for which
irrigated crop accumulation data are required, the test substance
shall be a product representative of the major formulation category
which includes the end-use product. (If the manufacturing-use
product is usually formulated into endr-use products comprising two
or more major formulation categories, a separate study must be
performed with a typical end-use product for each such category . )
(2) Test procedures* (i) Field accumulation studies on
irrigated crops should be conducted in at least two different sites
which are representative of the areas where irrigated crops are
expected to be grown.
(ii) Application, de irrigated crops should receive irriga-
tion water containing the test substance at the highest expected
concentration either consistent with the maximum rate recommended
on the product label at the original site of application (aquatic
food crop, aquatic non— crop, holding ponds) or consistent with the
maximum rate calculated from direct discharges.
(iii) Irrigation. Irrigated crops should be irrigated at the
maximum frequency consistent with good agricultural practices.
(iv) Sampling. (A) Foliage and/or crop produce samples
should be collected from the test crops receiving irrigation water
containing the test substance prior to the first irrigation treatment
and at the earliest possible normal harvest interval following the
..last irrigation treatment. • • ' . ' . • ' - • ;••'•'"
(B) Water samples should be collected from the irrigation
water at the time of each irrigation.' ' •-
(C) Soil samples should be collected from the site of the
irrigated crop prior to the first irrigation treatment, one day
after each irrigation treatment, and at harvest of the irrigated
crop. • ' ' •.••••• •
(iv) Analysis. Residue data should be obtained for the soil,
irrigation water, and irrigated crop samples collected during the
course of this study.
( d) Reporting and evaluation of data. In addition -to data '
submitted in response to the applicable reporting requirements
specified in § 160-5, the test report should contain the following
information;
(i) Analysis for residues of parent compound and degradates
in the test crops, the irrigation water, and soil. Decline curves
of the residues in soil should be included.
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(ii) A description of residue data variability for the test
crop, irrigation water, and soil sampled in this study.
(iii) Field test data, including:
(A) Dates of planting and harvesting;
(B) Method and frequency (times) of irrigation treatments;
(C) Sampling times and techniques;
(D) Stages of crop development at sampling times;
(1) Irrigation-to-harvest and irrigation-to-sampling intervals
for each irrigation treatment;
(F) Depth, weight, or volume of each sample, and weights and
volumes of aliquots taken for analysis;
(G) Flow data for irrigation water expressed in terms of
volume or linear flow; and
(H) Rainfall data, temperature monitoring data, and a
description of the general climatic conditions at the test sites*
(e) References. The following reference contains supplemental
information for developing a protocol for conducting an accumulation
study in irrigated crops: • .
(1) Demint, R.J., J«C» Pringle, Jr., A. Hattrup, V«F» Brans,
and .P.A. Prank. 1975. Residues in crops irrigated with water
containing trichloroacetic acid. J_. Agr. Food Ghent. 23:81-84,
[This paper presents a procedure for assessment of pesticide
carryover in irrigation water.]
(2) '[Reserved.]
§ 165-4 Laboratory studies of pesticide accumulation in fish.
(a) Purpose. The purpose of these studies is to determine if
pesticide residues accumulate in fish used as human food sources
and to determine the extent of pesticide residues in edible portions
of such fish. Data from pesticide accumulation studies in fish are
used by the Agency to establish label restrictions (e.g., to prevent
pesticide applications to certain sites so that there will be
minimal residues entering edible fish or shellfish such as catfish
or crayfish inhabiting rice fields). The data may also be used to
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provide information for the setting of tolerances or action levels
in these organisms where necessary.
(b) When required. (1) Data from a fish accumulation study
are required by 40 CFH § 158 to support the registration of an end-
use product intended for outdoor use (except domestic outdoor and
greenhouse uses), or aquatic impact uses involving direct discharge
of treated water into outdoor aquatic sites, except when any of the
criteria in paragraph (b)(2) of this section are satisfied. Data
from such a study are also required to support each application for
registration of a manufacturing-use product that could be legally
used to produce such an end-use product^ except when any of the
criteria in paragraph (b)(2) of this section are satisfied. See,
specifically, 40 CFR § 158.50 and § 158.130 to determine whether
these data must be submitted. Section II~A of this Subdivision
contains an additional discussion of the "Formulators" Exemption"
and who must submit the required data as a general rule.
(2) Fish accumulation data will not normally be required in
situations where the registrant can offer evidence acceptable to the
Agency showing that the active ingredient and/or its principal
degradation product(s):
(i) Will not reach water, or
(ii) Will not persist in water (i.e., has a half-life of
approximately four days or less), or
• "f-r** .
(iii) Has a relatively low potential for accumulation in fish
as indicated by an octanol/water .partition coefficient less than * _ ;
approximately 1000. *
(c) Combinedtesting. Testing conducted as described in this
section may be combined with testing conducted to meet the requirements
of § 72-6 of Subdivision E, Hazard Evaluation: Wildlife and Aquatic
Organisms, provided the test standards of each study are met,
(d) Test ^standards. Fish accumulation data submitted in res-
ponse to 40 CFR § 158.130 should be derived from testing which complies
with the general test standards in § 160-4 and all of the following
specific test standards:
(1) Test substance. Accumulation studies shall be conducted
using the active ingredient as the radioactively-tagged analytical
grade or as the technical grade. If the study requires testing
with a degradation product, the purest form that the applicant can
obtain shall be used.
(2) Test procedures. (i) Residue studies should be conducted
with radioisotopic (preferred) or non-radioisotopic analytical
techniques.
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(ii) Flow-through exposure studies are recommended. Exposure
systems must maintain a constant concentration of chemical in a non-
colloidal solution (use of carrier solvents to introduce the test
substance to dilution water is permissible).and the concentration
must not exceed 1/10 of the 96-hour ££50 of the test species.
Within these constraints, the concentration of the test substance
should be high enough to facilitate chemical identification of
residues in fish. Bluegill sunfish or channel catfish are the
preferred.species, although other species may be; appropriate. A
control (non-treated) group of fish is recommended.
(iii) Exposure duration is 28 days with depuration (withdrawal)
of 14 days with suggested sampling times and total residue analyses
. as follows s ..-•;.'
(A) Water: days 0, 7, 14, 21, and 28 of the accumulation
period;
(B) Fish: total residues in whole body, edible tissue, and
viscera should be determined on days 0, 3, 7, 14, 21r and 28 of the
accumulation period, and days 1, 3, 7, 10, and 14 of the depuration
period.
(iv) Residues in two samples of edible tissue and two samples
of viscera containing the highest residue levels during the
accumulation period should be identified (if sufficient material
exists). In general, extractable residues present at 0.05 ppm or
greater should be•• identified. . •. .
(v) The Agency recognizes that special circumstances may be
present (e.g., the occurrence of multiple persistent degradates,
particular use patterns, or accumulation mechanisms).under which
alternative experimental designs may be desirable. Therefore, the
registration applicant may wish to discuss with the Agency the
appropriateness of alternative experimental designs;for:fish
accumulation studies'(e.g., short-term kinetic' studies or simulated
field studies).
(e) Reporting and evaluationof data. In addition to the
applicable reporting requirements specified in § 160-5, the following
should be reported:
(1) A detailed description of the test conditions should be
provided. This should include water characteristics (e.g., dissolved
oxygen, pH, temperature, and dissolved salts), information on the
test organisms (scientific name, source, weight, observed mortality,
disease treatment, and acclimation procedures), and test methodology
{detailed protocol, organism loading ratio, lighting, temperature,
feeding schedule, and similar information).
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(2) Total residue levels in whole body, edible tissue, and
viscera, and in exposure water at all sampling times, including a
description of data variability, shall be reported, as well as the
identity of residues at specifed times.
(f) References. (1) The following reference is a review of
accumulation of pesticides in fish:
Hamelink, J.L., and A. Spacie. 1977. Fish and chemicals: The
process of accumulation* Ann. Rev. Pharmacol« Toxicol. 17:167-
177. [This paper contains information on the parameters, kinetics,
and processes that influence the accumulation of pesticides in
fish. It could provide useful background information for design of
accumulation studies*]
(2) The following references contain experimental procedures
relative to design of studies of pesticide accumulation with sunfish:
(i) Branson, D.R., G.E. Blau, H.C. Alexander, and W.B. Neely.
1975. Bioconcentration of 2,2',4,4*-tetrachlorobiphenyl in rainbow
trout as measured by an accelerated test. Trans» Am. Fish. Soc.
104:785792. [Accelerated accumulation tests such as those reported
in this paper may be an acceptable substitute for full-length studies
under certain conditions* Examples might include instances where
concerns about multiple persistent degradates exist.]
(ii) Krzeminski, S.F., C.K. Brackett, arid J.D. Fisher. 1975.
Fate of microbicidal 3-isothiazolone compounds in the environment:
Modes and rates of dissipation. J. Agr. Fogd Chegu 23:1060-1068.
[This is an example of a flow-through study.' It demonstrates high
levels of steadystate accumulation under steady dosing conditions
and a rapid residue decline.when the dosing rate goes to, zero..]
(iii) Macek, K.J., M.E. Barrows, R«F. Frasny, and B.H., Sleight,
III. 1975. Bioconcentration of 14Opesticides by bluegill sunfish
during continuous aqueous exposure. Pp. 119—142 in Structure
Activity Correlations in Studies of Toxicity and Bioconcentration
with Aquatic Organisms. G.D. Veith and D.E. Konasewich (eds).
Great Lakes Advisory Board. International Joint Commission.
Windsor, Ontario, Canada.
[•This is a good prototype for design of a protocol for study of
pesticide accumulation in fish,]
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§ 165-5 Field accumulation studies of aquatic non-target organisms.
(a) Purpose. Field accumulation studies are required to
determine if, following aquatic non-crop applications of pesticides,
pesticide residues are accumulated in the edible tissues of fish
that normally inhabit sites in or adjacent to these treated areas.
The residue-bearing fish subsequently may be used as human food
sources. Furthermore, these studies are needed to establish realistic
label restrictions necessary to protect man and the environment and
to provide information for determining if tolerances or action
levels may be needed. These studies complement the laboratory data
required for those uses by taking into account the contributions of
pesticide degradation, partitioning, and movement under field use
conditions in determining the amount and nature of the residues
available to the nontarget aquatic organisms via accumulation.
' ' ' : ' :';; .' : '• . -," . '
(b) When required. (1) Data from a field accumulation study
in aquatic nontarget organisms are required by 40 CFR § 158 to
support the registration of an end-use product:-
(i) which is intended for forestry use, aquatic non-crop use,
or aquatic impact use that results in direct discharges of treated
water into outdoor aquatic sites;
(ii) For which data from the laboratory fish accumulation study
(§165-4) show a potential for residues of the pesticide to accumulate*
(iii) For which no tolerance or action level for fish has
been granted.
(2) Data from such a study are also required to support each
application for registration of a manufacturing-use product which
legally could be used to make an end-use product described in
paragraph (b)(1) of this section. See, specifically, 40 CFR
§ 158.50 and § 158.130 to determine whether these data must be
submitted. Section II-A of this Subdivision contains an additional
discussion of the "Formulators" Exemption" and who must submit the
required data as a general rule.
(c) Combined testing. Testing conducted as described in this
section may be combined with testing conducted to meet the requirements
of § 164-2 (field dissipation studies for aquatic uses and aquatic
impact uses) or § 165-4 (laboratory studies of pesticide accumulation
in fish), provided the test standards of each study are met.
(d) Test standards. Aquatic non-target field accumulation
data submitted in response to 40 CFR § 158.130 should be derived from
testing which complies with the general test standards in § 160-4
and all of the following specific test standards:
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(1) Test substance. The test substance should be a typical
end-use product representative of a major formulation category
(e.g., wettable powder, emulsifiable concentrate, granular product)
and containing the active ingredient of the applicant's 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 to which the product belongs.
(i±) If the applicant's product is a manufacturing-use product
that legally could be used to make an end-use product for which non-
target organism-field accumulation data are required. The test
substance shall be a product representative of the major formulation
category which includes that end-use product; (If the manufacturing-
use product is usually formulated into end-use products comprising
two or more major formulation categories, a separate study must be
performed with a typical end-use product for each such category.)
(2) Test procedure. (i) The rate and method of test substance
application should approximate the intended' use pattern of the
pesticide.
(ii) Fish (bottom, middle, and surface feeders, if available)
including water, should be sampled in representative application
areas* ^ _
(iii) Sampling times for fish and water should include pre-
application, date of application, and immediate post-application
for 'each single or multiple-application of the test substance, and
then at 3, 7, 14, 21, and 28 days following the last application.
(iv) Residue analyses should be performed on the whole body
and edible tissue of fish and on the water samples for each sampling
interval.
(e) Reporting and evaluation of data. In addition to the
applicable reporting requirements specified in § 160-5, the reporting
requirements specified in §§ 164-3(e) and 165-4(e) apply.
(f) References. (1) Consult the references cited in § 164-
2(f) for guidance on the general conduct of aquatic non—target
organism field accumulation studies.
(2) Consult the references cited in § 165-4(f) for guidance
in the sampling and residue analysis of fish.
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