Overview of the Ecological Risk Assessment Process

in the Office of Pesticide Programs,

U.S. Environmental Protection Agency

__________

Endangered and Threatened Species Effects Determinations

Office of Prevention, Pesticides and Toxic Substances

Office of Pesticide Programs

Washington, D.C.

January 23, 2004

Acknowledgments

Authors, in alphabetical order:

Russell Jones, Office of Pesticide Programs, Biopesticides and Pollution
Prevention Division

John Leahy, Office of Pesticide Programs, Special Review and
Reregistration Division

Michele Mahoney, Office of Pesticide Programs, Environmental Fate and
Effects Division

Linda Murray, Office of Pesticide Programs, Registration Division

Edward Odenkirchen, Office of Pesticide Programs, Environmental Fate and
Effects Division

Richard Petrie, Office of Pesticide Programs, Antimicrobial Division

Carol Stangel, Office of Pesticide Programs, Special Review and
Reregistration Division

Ingrid Sunzenauer, Office of Pesticide Programs, Environmental Fate and
Effects Division

Zigfridas Vaituzis, Office of Pesticide Programs, Biopesticides and
Pollution Prevention

Division

Arthur Jean Williams, Office of Pesticide Programs, Field and External
Affairs Division

Reviewers, in alphabetical order:

Steven Bradbury, Office of Pesticide Programs, Environmental Fate and
Effects Division

William Jordan, Office of Pesticide Programs

Paul Mastradone, Office of Pesticide Programs, Registration Division

Karen McCormack, Office of Pesticide Programs, Environmental Fate and
Effects Division

Larry Turner, Office of Pesticide Programs, Field and External Affairs
Division

Scientists in the Office of Research and Development

Table of Contents

 TOC \f

I.  Purpose and Organization of This Document	7

II.  Statutory Framework	8

A.  Statutory Authority	8

B.  Authority to Require Data	8

C.  Definitions and Types of Pesticides	9

III.  Overview of the Office of Pesticide Programs	11

A.  Mission of the Office of Pesticide Programs	11

B.  Organizational Structure of the Office of Pesticide Programs	11

1.  Science-based Divisions	14

2.  Risk Management Divisions	14

3.  Science-based and Risk Management Divisions	15

4.  Other Divisions	15

C.  Regulatory Processes	16

1.  Section 3 Registrations	16

2.  Experimental Use Permits	17

3.  Emergency Exemptions	17

4.  Special Local Need Registrations	19

5.  Reregistration Process	19

6.  Registration Review	21

D.  Addressing Potential Concerns Related to Listed Species	21

IV.  Overview and Organization of the Environmental Fate and Effects
Division	23

A.  The Environmental Fate and Effects Division’s Procedures	24

B.  Data Requirements and Other Data Sources	25

C.  Processes to Support Sound Science	26

1.  Agency Guidance	26

a.  Guidelines for Ecological Risk Assessments	26

b.  Risk Characterization Handbook	26

c.  Peer Review Handbook	26

2. Tools to Promote Sound Science	27

a.  Pesticide Assessment Guidelines	27

b.  Standard Evaluation Procedures	27

c.  Databases	27

d.  Technology Teams	29

3. Internal Peer Review Mechanisms	29

a.  Data Evaluation Records	29

b.  Risk Assessments and Risk Characterizations	29

c.  Science Policy Panel	30

4.  External Peer Review and Scientific Advisory Panel	30

V.  Overview of OPP’s Screening-Level Ecological Risk Assessment
Process for Aquatic       Life, Wildlife, and Plants	31

A.  Problem Formulation	31

1.  Defining the Regulatory Action	31

2. The Nature of the Chemical Stressor Considered in the Risk Assessment
32

3.  Pesticide Use Characterization	33

4.  Identification of Assessment Endpoints	34

a.  Direct Effects	34

b.  Indirect Effects for Listed Species	34

c.  Effects on Listed Species Critical Habitat	35

5.  Measures of Effects and Exposure: The Use of Surrogate Organisms	35

6.  Identification of Data Gaps	36

B.   Analysis Phase	37

1.  Exposure Characterization	37

a.  Fate and Transport Data Requirements and Study Evaluation	37

b.  Aquatic Organism Exposure Modeling	40

(1).  General Approach	40

(2).  Special Aquatic Exposure Methods for Pesticide

Formulations 	42

c.  Terrestrial Organism Exposure Modeling	43

(1).  General Approach	43

(2).  Special Terrestrial Exposure Methods for Pesticide Formulations	44

d. Non-Target Plant Exposure Modeling	44

2.  Effects Characterization	45

a.  Registrant-Submitted Studies for Direct Effects of Pesticides	47

b.  Open Literature Studies for Direct Effects of Pesticides	47

(1).  ECOTOX	47

(2).  OPP Strategy for Conducting Literature Searches	48

c.  Open Literature Studies for Indirect Effects of Pesticides	49

d.  Open Literature Studies for Critical Habitat Evaluations	49

C.   Risk Characterization	49

1.  Integration of Exposure and Effects Data - The Risk Quotient for
Direct 		Effects	49

2.   Levels of Concern for Direct Effects - The Policy Tool for
Interpreting Risk Quotients for Direct Effects	50

3.  Comparison of Field and Laboratory Data for Direct Effects	51

4.  Indirect Effects Characterization for Listed Species	52

a. Indirect Effect Analyses Where One or More Animal Taxonomic Group RQs
Exceed the Endangered Species LOC	52

b. Indirect Effects Where One or More Plant Taxonomic Group RQs Exceed
the Endangered Species LOC	53

5.  Critical Habitat for Listed Species	54

6.  Description of Assumptions, Uncertainties, Strengths, and
Limitations of the Assessment	54

a.  Assumptions and Limitations Related to Exposure for All Taxa	54

b. Assumptions and Limitations Related to Exposure for Aquatic Species
55

(1).  Location of Species and Receiving Waters to Treated Field	55

(2).  Exposure for Aquatic Species Is Through the Dissolved Phase	55

(3).  Dissipation in the Modeled Water Body	55

(4).  Averaging Times for Aquatic Exposure	56

(5).  A Well-Mixed Pond	56

(6).  Watershed to Pond Ratio	56

(7).  100 Percent Pesticide Treatment of the Pond Watershed	57

(8).  Frequency of Exposure During a Given Year - 1 in 10 Year Return
Frequency	57

(9).  Dilution of Sediment	57

(10).  Spray Drift	58

c. Assumptions and Limitations Related to Exposure for Terrestrial
Animals	60

(1).   Location of Wildlife Species	60

(2).  Routes of Exposure	60

(3).  Incidental Pesticide Releases Associated with Use	62

(4).  Residue Levels Selection	62

(5).  Dietary Intake - The Differences Between Laboratory and Field
Conditions	63

d. Assumptions and Limitations Related to Effects Assessment	64

(1).  Sublethal Effects	64

(2). Age Class and Sensitivity of Effects Thresholds	65

(3).  Use of the Most Sensitive Species Tested	66

e.  Assumptions Associated with the Acute LOCs	67

VI.  Overview of OPP’s Species-specific Ecological Risk Assessment
Process for Aquatic        Life, Wildlife, and Plants	69

A.  Overview and Organization of FEAD	69

B. Purpose of the Species-Specific and Habitat-Specific Assessments	69

C.  Effects Determinations	70

D.  Information and Data Sources Used in the Species-specific and
Habitat-specific Assessments	71

1.  “DANGER” Program	71

2.  Biological Requirements and Habits of Listed Species	71

3.  Sub-county Commodity Information	72

4.  Geographic Features That May Preclude Exposure	72

5.  Incident Information	72

6.  Sales and Use Information	72

7.  Local Use Practices	73

8.  Monitoring Data	73

E.  Exposure Characterization in the Species-Specific and
Habitat-Specific Assessments	73

1.  Geographic Proximity	73

a.  A “DANGER” Query	73

b.  Sub-county Use of the Pesticide	73

2.  Refine Exposure Estimates Using Specific Assessment Methodologies	74

3.  Refine Exposure Based on Biological and Habitat Requirements	74

F.  Risk Characterization	75

1.  Incident Information	75

2.  Sales and Use of the Pesticide	76

3.  Local Use Practices	76

4.  Monitored Levels in the Environment	76

G.  Assumptions	76

H.  Environmental Baseline and Analysis of Cumulative Effects	77

VII.  List of Support Documents	79

VIII.  References	83

Appendices

Appendix A.	Overview of OPP’s Screening-Level Ecological Risk
Assessment Process for Antimicrobial Pesticides	85

Appendix B.	Overview of OPP’s Screening-Level Ecological Assessment
Process for Biological Pesticides 	91

Overview of the Ecological Risk Assessment Process in the

Office of Pesticide Programs, Environmental Protection Agency

I.  Purpose and Organization of This Document tc \l1 "I.  Purpose and
Organization of This Document

The purpose of this document is to provide an overview of the
Environmental Protection Agency’s (EPA) ecological risk assessment
process for the evaluation of potential risk to endangered and
threatened (listed) species from exposure to pesticides.  The
assessments described in this document are conducted by the Office of
Pesticide Programs (OPP).

Organized into eight sections and two appendices, this document begins
with a description of the purpose and organization of the document
(Section I).  It continues with a brief overview of the statutory
framework under which OPP operates (Section II), followed by a
discussion of  OPP’s mission and organizational structure, and basic
information about OPP’s regulatory processes (Section III).  Section
III also acknowledges the importance of evaluating regulatory actions
for their potential impact to listed species and briefly describes the
steps being taken to ensure that listed species concerns are addressed.

Section IV provides an overview of the Environmental Fate and Effects
Division (EFED), which conducts most of the initial screening-level
assessments to evaluate the potential impact of pesticides on non-target
species, including listed species.  This section addresses EFED’s
procedures, data requirements, and processes to support the development
of ecological assessments based on sound science.

Section V provides a comprehensive review of EFED’s screening-level
assessment process, which is based on risk assessment procedures
outlined in guidance documents and standard evaluation procedures.  If a
pesticide is determined to potentially impact listed species, a
species-specific assessment, which is described in Section VI, is
conducted by another OPP division, the Field and External Affairs
Division (FEAD).

Sections V and VI summarize the screening-level and species-specific
assessments that are generally conducted in OPP.  It should be noted,
however, that the ecological risk assessment process within OPP may, on
a case-by-case basis, incorporate additional methodologies, models, and
lines of evidence that are technically appropriate for risk management
objectives.  Examples of additional information and methodologies
include monitoring and incident data and evaluation of routes of
exposure not routinely considered, but suggested by other lines of
evidence.

Finally, the document concludes with a list of support documents
(Section VII), references (Section VIII), and appendices.

II.  Statutory Framework tc \l1 "II.  Statutory Framework

A.  Statutory Authority tc \l2 "A.  Statutory Authority

EPA regulates pesticides under two major federal statutes: the Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Federal
Food, Drug, and Cosmetic Act  (FFDCA), both amended by the Food Quality
Protection Act (FQPA) of 1996.  Under FIFRA, pesticides intended for use
in the United States must be registered (licensed) by EPA before they
may be sold or distributed in commerce.  EPA will register a pesticide
if scientific data provided by the applicant show that, when used
according to labeling directions, it will not cause “unreasonable
adverse effects on the environment”. (FIFRA defines “unreasonable
adverse effects on the environment” as “any unreasonable risk to man
or the environment, taking into account the economic, social and
environmental costs and benefits of the use of any pesticide .....”)
Under FFDCA, the Agency is responsible for setting tolerances (maximum
permissible residue levels) for any pesticide used on human food or
animal feed.

With the passage of the Food Quality Protection Act (FQPA) in 1996, both
major pesticide statutes were amended to establish a more consistent,
protective regulatory scheme grounded in sound science.  FQPA mandated a
single, health-based standard for setting tolerances for pesticides in
foods; provided special protections for infants and children; expedited
approval of safer pesticides; created incentives for the development and
maintenance of effective crop protection tools; and required periodic
re-evaluation of pesticide registrations and tolerances to ensure that
the scientific data supporting pesticide registrations would remain
up-to-date in the future. It should be noted that FQPA also limited the
consideration of benefits when setting tolerances.  FQPA did not address
the consideration of ecological risk.

For this document, the focus will be on environmental risks, which are
regulated under FIFRA.

B.  Authority to Require Data tc \l2 "B.  Authority to Require Data

By law, the Agency has the authority to obtain data under three
provisions of FIFRA:

FIFRA 3(c)(1)(F) - Authorizes the Agency to require data to support an
application for registration of a pesticide.  OPP’s data requirements
are set forth in 40 CFR Part 158, but EPA has broad authority to ask for
additional data or waive requirements, as appropriate. These data
requirements are discussed under Section IV of this document.

FIFRA 3(c)(2)(B) - Provides the authority to require additional data on
currently registered products.  These data must be “required to
maintain in effect an existing registration of a pesticide.”  If EPA
imposes a data requirement under this authority, EPA must allow enough
time to design the study and generate data.  In addition, EPA must
comply with the Paperwork Reduction Act.

FIFRA Section 6(a)(2) - Requires that pesticide registrants inform the
Agency of any relevant adverse effects information relating to their
products, even though it was not  formally requested by EPA.
Information reportable under this provision includes new information
derived from scientific studies, such as efficacy failures of
antimicrobial products and pest resistance.  Incidents of adverse
effects resulting from the use of pesticide products are also reported.
 The information collected under 6(a)(2) is tracked and regularly
distributed to the various divisions in OPP, as appropriate. [See 40 CFR
15 and http://www.epa.gov/pesticides/fifra6a2/ for more information
concerning EPA’s published guidelines and regulations for Section
6(a)(2).]

C.  Definitions and Types of Pesticides tc \l2 "C.  Definitions and
Types of Pesticides

Based on the Code of Federal Regulations (CFR), a pesticide is defined
as:

“Any substance or mixture of substances intended for preventing,
destroying,

repelling, or mitigating any pest, or intended for use as a plant
regulator,

defoliant, or dessicant....” (40 CFR 152.3).

Substances that are not covered in this definition include, but are not
limited to, deodorizers, non-toxic physical barriers against pests,
fertilizers or other plant nutrient substances which do not target pest
species.  Some products meeting the definition of a pesticide are exempt
from requirements of FIFRA, such as those for human drug use only,
pesticide treated articles (clothing, paints, etc.), pheromones used in
traps, food preservatives, or natural repellants such as cedar wood  (40
CFR 152).

Based on 40 CFR 152.3, an active ingredient and an inert ingredient,
respectively, are defined as follows:

“Any substance (or group of structurally similar substances if
specified by the Agency) that will prevent, destroy, repel or mitigate
any pest, or that functions as a plant regulator, dessicant, or
defoliant within the meaning of FIFRA section 2(a), except as provided
in §174.3 of this chapter.”

“Any substance (or group of structurally similar substances if
specified by the Agency), other than an active ingredient, which is
intentionally included in a pesticide product, except as provided in
§174.3 of this chapter.”

Many different types of pesticides are available.  They may be grouped
according to the pests they control, their use pattern, or their
chemical class.  The following list provides some examples of the
categories of pesticides that are grouped according to the pests they
control:

Insecticides - act pesticidally against the growth or survival of
insects.  Also includes specific types such as miticides, mosquito
larvicides or adulticides;

Herbicides - act pesticidally against plants, weeds, or grasses;

Rodenticides - act pesticidally against rats or other rodents;

Avicides - act pesticidally against damaging bird populations;

Fungicides - act pesticidally against fungi on food or grain crops;

Nematicides - act pesticidally against nematodes;

Fumigants - gaseous pesticides used for invertebrate and fungal control;

Antimicrobials - act pesticidally against microscopic organisms on a
variety of sites;

Plant Growth Regulators - accelerate or retard plant growth rates;

Insect Growth Regulators - retard insect growth;

Biopesticides - naturally occurring substances with pesticidal
properties, including microbial pesticides, biochemical pesticides and
plant incorporated protectants;

Piscicides - act pesticidally against unwanted or invasive fish
populations; and

Molluscides - act pesticidally against slugs, snails, or bivalves.

Pesticides may also be categorized into the following general use
patterns in order to determine registration data requirements:
terrestrial, aquatic, greenhouse, forestry, domestic outdoor, and indoor
(40 CFR 158).  The terrestrial, aquatic, and greenhouse patterns are
further divided into food crop and nonfood applications.

Pesticides that have similar chemical structures often have similar
modes of action, as well as comparable fate and transport properties.
Such chemicals may be grouped in the same chemical class.  Some examples
of chemical classes include the following:

Insecticides: chloronicotinyl compounds (e.g., imidacloprid, nicotine),
N-methyl carbamates (e.g., carbaryl, aldicarb), organophosphorus
compounds (e.g., chlorpyrifos, diazinon), and pyrethroids (e.g.,
cyfluthrin, cypermethrin), and others.

Herbicides:  benzoic acids (e.g., dicamba), chloroacetanilides (e.g.,
alachlor, metolachlor), chlorophenoxy acids/esters (e.g., 2,4-D, MCPA),
imidazolinones (e.g., imazamox, imazapyr), sulfonylureas (e.g.,
bensulfuron-methyl, rimsulfuron), thiocarbamates (e.g., butylate,
molinate), and triazines (e.g., atrazine, simazine), and others.

Fungicides: benzimidazoles (e.g., benomyl, thiabendazole), carboxamides
(e.g., carboxin, flutolanil), and dithiocarbamates (e.g., maneb, ziram),
and others.

III.  Overview of the Office of Pesticide Programs tc \l1 "III.
Overview of the Office of Pesticide Programs

A.  Mission of the Office of Pesticide Programs tc \l2 "A.  Mission of
the Office of Pesticide Programs

EPA’s overarching mission is to protect human health and to safeguard
the environment – air, water, and land – upon which life depends.
An important component of this goal is the protection of  human health
and the environment from unreasonable adverse effects resulting from the
use of pesticides and to assure that pesticide residues that may occur
in food are safe.

OPP’s mission is both challenging and complex. OPP regulates the use
of all pesticides in the United States and establishes maximum levels
for pesticide residues in food, thereby safeguarding the nation's food
supply.  Pesticides play a role in many aspects of everyday life, from
agriculture and greenhouses to lawns, swimming pools, hospitals, and
food service establishments. There are about 20,000 registered pesticide
product formulations, containing approximately 675 active ingredients
and 1,835 other ingredients. About 470 pesticide active ingredients are
used in agriculture, and EPA has established more than 9,000 tolerances
(maximum allowable residue limits) for pesticides that may be present in
food.

EPA's regulation of pesticides directly or indirectly affects
approximately 30 major pesticide producers, another 100 smaller
producers, 2,500 formulators, 29,000 distributors and other retail
establishments, 40,000 commercial pest control firms, one million farms,
three and a half million farm workers, several million industry and
government users, and virtually all households.

B.  Organizational Structure of the Office of Pesticide Programs tc \l2
"B.  Organizational Structure of the Office of Pesticide Programs

To fulfill its mission, OPP has nine divisions and the immediate office
of OPP’s Office Director. Approximately 800 people carry out a wide
range of activities related to pesticide regulation and risk management.
In addition, a large number of people in other EPA offices, including
EPA’s regional offices, provide administrative, legal, enforcement,
and research support.  Figure 1 provides a graphical representation of
the organizational structure, which is described later in this section.

 	It should be noted that in OPP, a distinction is made between the role
of the risk assessor and risk manager.  Risk assessors use information
and data concerning pesticide exposure and human and ecological effects
to estimate the likelihood of adverse outcomes with varying pesticide
use scenarios.  Risk managers determine how the pesticide will be
regulated.  In regulating ecological effects, the regulatory decision is
based on the results of the risk assessment and potential mitigation
options, but may also include the integration of social considerations
and economic factors (benefits information), and legal requirements.
Trade-offs between different regulatory actions are evaluated, and value
judgments applied to reach a decision.

Risk management addresses a variety of considerations that range from
scientific to socio-economic considerations.  The risk analysis focuses
on providing an unbiased evaluation of risk, with assumptions and
uncertainties clearly articulated.  By separating the functions of the
pesticide risk assessment and risk management processes, within the
broader risk management framework, the integrity and transparency of the
scientific analyses are maintained.

The policy regarding the interface between risk assessment and risk
management grew out of a National Research Council report in 1983,
referred to as the “Red Book”, which emphasized the distinction
between the two functions (National Research Council, 1983.)  The Red
Book proposed a strong separation of risk assessment and risk
management, but also recognized the need and importance of continual
interaction between the functions.  Although the Red Book focused on
human health, the policy was expanded to address ecological risk as
well.

Figure 1: OPP Organizational Structure

Office of the Director

Environmental Fate and Effects Division

Risk Assessment

Health Effects Division

Risk Assessment

Registration Division

Risk Management

Special Review and Reregistration Division

Risk Management

Biopesticides and Pollution Prevention Division

Risk Assessment and Risk Management

Antimicrobials Division

Risk Assessment and Risk Management

Biological and Economic Analysis Division

Usage Data, Benefits Analysis, and Chemistry Labs

Field and External Affairs Division

Field Programs, Policy, and Regulation Support and Communications

Information Resources and Services Division

Information Management and Systems Support

1.  Science-based Divisions tc \l3 "1.  Science-based Divisions

The following divisions focus primarily on conducting the risk and
benefit assessments for conventional pesticides; they do not perform
risk management functions.  The results of the science assessments,
including the ecological risk assessment for listed species, are
forwarded to the risk management divisions discussed in the next
section.

Environmental Fate and Effects Division (EFED) - Conducts
screening-level risk assessments to assess the ecological risk to
non-target species, including the potential impact on listed species,
and conducts refined ecological risk assessments.  (See Section V for an
overview of OPP’s screening-level assessment process.)  In addition,
EFED evaluates drinking water exposure and sends its evaluations to the
Health Effects Division to be considered in their human health risk
assessments.

Health Effects Division (HED) - Reviews data on pesticide human health
effects and characterizes and assesses risks to humans and domestic
animals, which are considered in risk management decisions.  As part of
the assessment process, HED’s Metabolism Assessment Review Committee
(MARC) considers whether pesticide metabolites and/or breakdown products
are of toxicological concern and should be included in the dietary
exposure/risk assessment and/or tolerance expression for foods and
livestock feeds. In addition, a screening methodology has been developed
to evaluate lower toxicity inert and active ingredients to determine
that there is a reasonable certainty that no harm will result from the
aggregate exposure to the pesticide residues before granting a tolerance
or exemption from the requirement of a tolerance.

HED does not participate directly in the development of an ecological
risk assessment.  However, HED does review acute mammalian toxicity data
conducted on the active ingredient and formulations as well as
two-generation reproductive toxicity tests, which are used by EFED to
characterize mammalian wildlife toxicity.  HED also reviews pesticide
residue dissipation in food crops and animal feed items, which are used
to estimate foliar dissipation half-lives for multiple application
exposure modeling for wildlife. In addition, the information from the
MARC (see Section V. B.2) and from the evaluation of lower toxicity
inert and active ingredients (see Section V.A.2) may be useful for
evaluating pesticide impacts to ecological resources.

Biological and Economic Analysis Division (BEAD) - Assesses pesticide
use and benefits information and operates analytical chemistry and
antimicrobial testing laboratories.

2.  Risk Management Divisions tc \l3 "2.  Risk Management Divisions

The Registration Division and Special Review and Reregistration Division
are responsible for making the final risk management decision on
conventional pesticides, primarily through the registration and
reregistration processes.  These divisions do not conduct risk
assessments.

Both divisions consult with HED and EFED on questions related to the
human and environmental risk assessments, respectively, and potential
mitigation options once they have received the risk assessments and have
begun to develop the regulatory decision.  If necessary, a risk
assessment may be conducted again at the request of the risk management
division.  This may be necessary because of changes made to the
registration related to mitigation options, which could alter the
results of the assessment.

Registration Division (RD) - Coordinates and manages the regulatory
actions involving the entry into the market place of new conventional
pesticide products.  These actions include the registration of new
pesticide products, new uses of existing pesticide products, product and
label amendments, experimental use permits, tolerances, and emergency
exemptions based upon scientific evaluation of data and other
considerations.

Special Review and Reregistration Division (SRRD) - Coordinates and
manages the reregistration of existing pesticides and reassessment of
tolerances based upon a scientific evaluation of data and other
considerations.

3.  Science-based and Risk Management Divisions tc \l3 "3.
Science-based and Risk Management Divisions

In OPP, two divisions perform both risk assessment and risk management
functions.  It should be noted, however, that the role of risk assessor
and risk manager in these divisions are never assumed by the same
person.

Antimicrobials Division (AD) - Provides full regulatory service for
antimicrobial pesticides.  This includes the registration and
reregistration processes; conducting assessments for human
health/dietary risk; residential and industrial worker exposure,
environmental fate and ecological effects, drinking water exposure,
product and residue chemistry, and the efficacy of public health
pesticides.

Biopesticides and Pollution Prevention Division (BPPD) - Focuses on
biologically-based pesticides and measures that will reduce pesticide
risks.  BPPD’s functions include  risk and benefit assessments,  risk
management, tolerance reassessment, and the Pesticide Environmental
Stewardship Program (PESP).  PESP is a voluntary partnership between EPA
and the pesticide user community to reduce risk from pesticide use in
agricultural and non-agricultural settings.

4.  Other Divisions tc \l3 "4.  Other Divisions

The remaining two divisions provide unique support functions for OPP.

FEAD - Coordinates OPP’s policies and regulatory development,
international and field programs, such as Certification and Training,
Agricultural Worker Protection Program, and others.  FEAD also
administers and coordinates the field implementation of the  Endangered
Species Protection Program and conducts species-specific risk
assessments for listed species and their designated critical habitat.
(See Section VI for further detail on the refined assessment process.)
In addition, FEAD provides region/state/tribal coordination and
assistance, legislation and Congressional interaction, and communication
and outreach activities.

Information Resources and Services Division (IRSD) - Provides
information and computer support for OPP, maintains OPP’s Web site and
OPP databases, handles the Public Docket, and processes FIFRA section
6(a)(2) submissions.

C.  Regulatory Processes tc \l2 "C.  Regulatory Processes

The two main regulatory processes in OPP are registration and
reregistration.  Registration focuses on decisions that allow new
pesticide products to enter the market place or that allow registrants
to make changes to the way existing pesticide products are sold,
distributed, or used.  While many registration decisions involve minor
changes or applications for new products that are identical to currently
registered pesticides, EPA devotes considerable resources to the review
of applications involving new active ingredients and applications
involving new uses of currently registered pesticides.

Reregistration is the review of older pesticides to ensure that they
meet current health, safety, and environmental standards.  The goal is
to update labeling and use requirements and reduce risks associated with
older pesticides, which were registered when the standards for
government approval were less stringent than they are today.

1.  Section 3 Registrations tc \l3 "1.  Section 3 Registrations

Section 3 of FIFRA authorizes EPA to register new pesticide products and
new uses of existing pesticide products for use in the United States.
In registering pesticide products, EPA may place restrictions on the
site or crop on which it is used; the method, amount, frequency, and
timing of its use; and the storage and disposal practices. Some
pesticides may be registered for more limited use in certain states.  In
addition, States, Tribes and Territories can place further restrictions
on EPA-registered pesticide products used or sold within their own
jurisdictions.

For a Section 3 registration action, the pesticide manufacturer submits
to EPA a  registration application, which includes the following
information:

Required test data;

Information concerning the manufacturing process;

Product chemistry;

Human and environmental risk data packages;

Tolerance information, consisting of information about pesticide
residues on food; and

Labeling information.

RD processes the application and tracks it. A project manager is
assigned who:

Completes a detailed review of the application;

Assigns and coordinates the appropriate scientific review;

Sets priorities and a timetable;

Coordinates administrative action; and

Communicates with the pesticide applicant or registrant concerning the
review of its application.

RD assigns the scientific review to HED for an evaluation of human
health risks and to EFED for evaluating environmental risks, including
potential risks to listed species. HED integrates all the human health
effects and exposure data into a comprehensive health risk assessment to
assess the potential impact that the pesticide product or active
ingredient will have on the human population.  At the same time, EFED
integrates scientific ecological effects and exposure information into
an environmental risk assessment to assess potential impacts on the
environment.  Both the health and environmental risk assessments undergo
a process of internal peer review by scientific experts.

RD’s policy is to send forward all new chemicals submitted for a
Section 3 registration to EFED and HED for a complete scientific review.
  For ecological risk, EFED provides an initial review and risk
assessment for non-target species, including listed species.  This
assessment is conducted using data, which are required based on the uses
of the pesticide.

Some pesticide uses, such as indoor application, are screened in RD to
determine if there is a potential exposure to non-target organisms.  If
there is no exposure, these uses may not require environmental fate and
ecotoxicity data or a full scientific review.  For example, some
specialized uses, such as indoor greenhouse applications, are screened
to determine if there is a potential to effect non-target organisms
through pesticide disposal.  If not, data are not required and an
ecological assessment is not conducted.

Section 3 amendment actions are screened in Registration Division to
determine if there is an obvious change from the present labeled use.
Those actions which indicate a change in the use are sent to the science
divisions for review.

In cases where EFED’s screening-level ecological risk assessment
raises potential concerns related to listed species, FEAD conducts a
species-specific evaluation to refine the assessment.  EPA is
implementing internal procedures to ensure that FEAD is routinely
notified and has an opportunity to conduct its analysis if potential
concerns related to listed species are identified.

After EFED and HED submit their risk assessments to the Registration
Division, RD reviews the risk assessments and develops potential risk
mitigation measures.  RD makes a registration determination based on the
statutory standards of FIFRA and FFDCA. If the application fails to meet
these standards, RD notes the need for more or better data, labeling
modifications, and/or use restrictions, and communicates the
deficiencies to the applicant.  If the application is approved, EPA will
establish a tolerance if the pesticide is intended for use on food or
feed and publishes a notice in the Federal Register.

2.  Experimental Use Permits tc \l3 "2.  Experimental Use Permits

Under FIFRA section 5 and the regulations (40 CFR 172), EPA may
authorize field testing of unregistered pesticides through an
experimental use permit (EUP).  Generally the Agency issues EUPs for
field experimentation involving 10 acres or more of land or 1 acre or
more of surface water.  The EUP establishes conditions for limiting the
transportation, application, and disposal of unregistered test products.
 The granting of an EUP also limits the sale and distribution of the
test product only between approved participants in the test program, and
use of the test product under conditions specified in the EUP.
Pesticide companies typically request EUPs for efficacy testing and/or
crop-specific residue chemistry data. Use-specific data are required to
support an EUP, but are more limited in scope than for a Section 3.
These data requirements (Section 112-1 in Support Document #34) along
with the application procedures are described in Support Document #34.
RD’s policy is to send forward the core ecological and environmental
fate data set if the EUP is for an outdoor use .  This EFED review
includes  consideration of listed species.

3.  Emergency Exemptions tc \l3 "3.  Emergency Exemptions

Section 18 of FIFRA authorizes EPA to allow States and Federal agencies
to apply a pesticide for an unregistered use for a limited time if EPA
determines that emergency conditions exist.   Most requests for
emergency exemptions are made by state lead agricultural agencies,
although the United States Department of Agriculture (USDA), United
States Department of the Interior, and other Federal agencies also have
requested exemptions. The process generally takes place as follows:

Growers in particular regions identify a potential pest control problem
situation that registered pesticides will not alleviate. The growers
contact their state lead agency (usually the state department of
agriculture) and request that the agency apply to EPA for a Section 18
emergency exemption for a particular use. The state agency evaluates the
requests and submits its request to EPA for an emergency exemption if it
believes the request is warranted. The uses are requested for a limited
period of time, no longer than one year (except in the case of
quarantine exemptions, which may be authorized for three years), to
address the emergency situation only. To be responsive to the states and
growers, EPA attempts to make decisions on the requests within 50 days
of receipt of the application.

During this 50-day time period, EPA performs a multi-disciplinary risk
assessment of the requested use, relying largely on data that have
already been reviewed for the pesticide. A dietary risk assessment, an
occupational risk assessment, and an assessment of the emergency are
conducted prior to making a decision. In addition, an ecological risk
assessment, which includes listed species and non-target organisms, is
also conducted.  Within EFED, these assessments are given a high
priority and thus conducted in an expedited basis.  The procedures for
these risk assessments are the same as for Section 3 registrations, but
are limited to the scope of the Section 18 request.  The Agency's
evaluation also includes an assessment of the progress toward
registration for the use in question.

Section 18 actions are screened in RD to determine if there is potential
outdoor impact prior to referral to EFED for a screening-level risk
assessment.  For any action requiring a screening-level assessment, EFED
conducts an assessment, which includes the evaluation of potential
impacts to listed species.  Because of statutory time restraints, these
reviews require rapid turnaround and often consist of EFED simple
refinements of previous assessments for similar uses and rates in the
same geographic area.  If preliminary concerns are determined, refined
assessments are requested from FEAD

Actions that are repeated for a second year for the same use and
geographic area are not referred for review. However, should they return
for a third year they are again sent to EFED for review to determine if
there have been any changes.

If the emergency appears valid and the risks are acceptable, EPA
approves the emergency exemption request. EPA will deny an exemption
request if the pesticide use may cause unreasonable adverse effects on
health or the environment, or if emergency criteria are not met. As a
matter of course, a state may withdraw an exemption request at any point
in the process.

If a need is immediate, a state agency may issue a “crisis
exemption” under which the State may use the unregistered pesticide
product for up to 15 days or longer if a specific exemption is pending.
The state notifies EPA of this action prior to issuing the crisis
exemption, and EPA performs a cursory review of the use to ensure there
are no obvious concerns.  If concerns are noted, EPA confers with the
state, and under extreme cases may not allow a crisis to be declared. If
the state follows up the crisis with, or has already submitted, an
emergency exemption request, the use may continue under the crisis
exemption until EPA has made a decision on the request.

The nature of crisis exemptions precludes pre-use review of potential
ecological effects, including the assessment for potential impacts to
listed species.  However, if the use is to continue beyond the 15-day
limit that is allowed, the actions are referred to EFED for a
screening-level assessment.  If EFED determines there are concerns
regarding listed species, the action follows the process previously
outlined and FEAD conducts a species-specific assessment..

4.  Special Local Need Registrations tc \l3 "4.  Special Local Need
Registrations

Under Section 24(c) of FIFRA, states may register for use only in that
state an additional use of a federally registered pesticide product or a
new end use product to meet special local needs (SLN) as long as there
is both a demonstrated "special local need," and a tolerance, exemption
from a tolerance, or other clearance under FFDCA.  “Special local
need” means an existing or imminent pest problem within a state for
which the state lead agency, based upon satisfactory supporting
information, has determined that an appropriate federally registered
pesticide product is not sufficiently available.  EPA reviews these
24(c) requests and may approve or disapprove the state action. If the
action is not disapproved, it becomes a permanent registration under
Section 3.   States may not register pesticide products with new active
ingredients under Section 24(c).

5.  Reregistration Process tc \l3 "5.  Reregistration Process

Under Section 4 of FIFRA as amended in 1988, EPA is reviewing older
pesticides (those initially registered before November 1, 1984) to
ensure that they meet current scientific and regulatory standards.  This
process, called reregistration, considers the human health and
ecological effects of pesticides and results in decisions to reduce
risks that are of concern.  EPA also is reassessing tolerances
(pesticide residue limits in food) to ensure that they meet the safety
standard established by FQPA.  EPA has integrated reregistration and
tolerance reassessment to most effectively accomplish the goals of both
programs.

Through the reregistration program, EPA is reviewing the human health
and environmental effects of groups of related pesticide active
ingredients.  When EPA completes the reregistration review and risk
management decision for a pesticide, the Agency generally issues a
Reregistration Eligibility Decision (RED) document. The RED summarizes
the risk assessment conclusions and outlines any risk reduction measures
necessary for the continued registration of the pesticide in the U.S.

EPA may also issue an Interim Reregistration Eligibility Decision (IRED)
for a pesticide that is undergoing reregistration, requires a
reregistration eligibility decision, and also needs a cumulative
assessment under FQPA. The IRED, issued after EPA completes the
individual pesticide's aggregate risk assessment, presents an interim
decision for the pesticide undergoing reregistration.  It may include
risk reduction measures -- for example, reducing risks to workers or
eliminating uses that the registrant no longer wishes to maintain -- to
gain the benefits of these changes before the final RED can be issued
following the Agency's consideration of cumulative risks.

To be declared “eligible” for reregistration, pesticides must meet
current scientific and regulatory standards.  The pesticide must have a
substantially complete database and must not cause unreasonable adverse
effects to human health and the environment when used according to
Agency approved labeling directions and precautions.

In addition, all pesticides with food uses must meet the safety
standard of Section 408 of the FFDCA, as amended by FQPA. FFDCA as
amended by FQPA also requires the reassessment of all existing
tolerances and tolerance exemptions within 10 years, to ensure that they
meet the safety standard of the new law.

Reducing risks is an important aspect of the reregistration program.
EPA works with stakeholders including pesticide registrants, growers and
other pesticide users, environmental and public health interest groups,
the States, USDA and other Federal agencies, and others to develop
voluntary measures or regulatory controls needed to effectively reduce
risks of concern.  Almost every RED includes some measures to reduce
human health and/or ecological risks.  The possible ways of achieving
risk reduction are extensive and include measures such as canceling
pesticide products or deleting uses; declaring certain uses ineligible
or not yet eligible (and then proceeding with follow-up action to cancel
the uses or require additional supporting data); phasing out uses;
restricting use of products to certified applicators; limiting the
amount or frequency of use; improving use directions and precautions;
adding more protective clothing and equipment requirements; requiring
special packaging or engineering controls; requiring no-treatment buffer
zones; requiring spray drift labeling; employing ground water, surface
water, or other environmental and ecological safeguards; and other
measures.

While assessing and mitigating human health risks is a significant
aspect of the reregistration program, assessing and mitigating
ecological risks also is an important part of the reregistration review
process.  In developing REDs and IREDs, the Agency’s internal risk
management process includes an evaluation of each ecological effects
assessment by the ECOR Committee (Ecological Review Group) to ensure
that ecological risks are fully considered and ecological risk
mitigation options are fully vetted. The group consists of staff level
personnel from FEAD, BEAD, RD, EFED, and SRRD.  Issues related to listed
species are discussed by this group and are addressed in the regulatory
document that is prepared.

Specifically, SRRD  has developed the following procedures to ensure
high quality and consistent management of issues related to listed
species during pesticide reregistration.

History of the Chemical Relative to Listed Species - When a chemical is
scheduled for reregistration, the Chemical Review Manager (CRM) conducts
an analysis of the chemical file to determine if the following
information is available:  incidents involving listed species, earlier
risk assessments indicating potential risks of concern, consultations
with the Services, a Biological Opinion or other indications of concern
for risks to listed species.  A summary of this analysis is shared with
the risk assessors and program managers in EFED and FEAD respectively
and is included in the regulatory history section of the RED for the
chemical.

Summary of the Ecological Risk Assessment - When the ecological risk
assessment is delivered to SRRD, the CRM carefully reviews the
assessment, noting discussion of potential risks to listed species.  The
CRM summarizes the risk conclusions in the risk summary section of the
RED.  Additionally, review managers meet with risk assessors to ensure
they have an accurate understanding of the risk conclusions and have
appropriately summarized them in the RED.

ECOR Review and Recommendations - For any chemical with potential risks
to non-targets, including listed species, the CRM schedules a meeting
with ECOR to ensure key experts in FEAD, EFED, RD, and BEAD are aware of
the risk picture.  Working together they develop a strategy to
appropriately address risks to listed species and can initiate
communications with other stakeholders as needed.

Develop the Risk Management Decision - Through ECOR, the CRM works with
experts in FEAD and EFED to develop the risk management decision and
language that reflects the regulatory decision and rationale sections of
the RED.

Ensure Any Post-RED Changes Still Meet the Risk Management Goals - If,
during a public comment period following publication of the RED,
comments are submitted relating to risks to listed species, the CRM
consults with FEAD and OGC if necessary to determine whether the comment
affects listed species’ risks.

Also, if changes in the regulatory decision are indicated from comments
submitted on any issue, the CRM discusses the comment(s) and alternative
risk management options with FEAD and EFED to ensure that any new
decision still meets the goals of the decision reflected in the RED.

6.  Registration Review tc \l3 "6.  Registration Review

 FIFRA 3(g) specifies that EPA establish procedural regulations for
conducting registration review and that the goal of the regulations
shall be the Agency review of pesticide registrations on a 15-year
cycle.  An Advance Notice of Proposed Rulemaking was issued in 2000,
which alerted stakeholders that EPA was beginning to develop the
required procedural regulations.  It explained EPA’s preliminary
interpretation of the authorizing legislation, presented EPA’s goals
in implementing the statutory provisions, presented the Agency’s
initial concept of how the registration review program might operate,
identified several issues that needed to be addressed, and invited
public comment.  Since that time, OPP has continued to work on designing
the program and is working on the proposed rule-making.

D.  Addressing Potential Concerns Related to Listed Species tc \l2 "D.
Addressing Potential Concerns Related to Listed Species

EPA acknowledges the importance of evaluating the regulatory actions
described earlier for their potential to impact listed species.  This
evaluation may include conducting a screening-level assessment to
determine if there is a potential concern.  If a potential concern is
identified, a species-specific assessment by FEAD may be warranted.

The assessments conducted, either at the screening or the more refined
species-specific level, need to be based on a sound scientific process.
This process entails using sound scientific  methods, developing
adequate supporting tools such as databases, and conducing adequate peer
review to further strengthen the process.  OPP continually works on
incremental improvements to aspects of the scientific process, which are
consistent with internal Agency policy and evolving Federal
requirements.

For example, EFED has developed guidance to ensure consistent
consideration and use of information in the open literature for
ecological risk assessments of pesticide effects (Support Document #71).
 This guidance is for use by EFED scientists and steps to implement the
guidance have been initiated.  The database that will be used to search
the open literature will be EPA’S ECOTOX, a comprehensive  tool for
locating chemical toxicity data for aquatic life, terrestrial plants and
wildlife.  Relevant literature for ECOTOX is retrieved using a
comprehensive search strategy designed to locate worldwide aquatic and
terrestrial ecological effects literature.  This database is also
user-friendly, publicly-available, quality-assured and economical.  (See
Section V.B.2.b of this document for further information on the use of
open literature data.)

EPA also recognizes that effective communication and administrative
processes are needed between risk assessment and risk management
divisions if a potential concern related to listed species is
identified.  To help EPA meets its obligations under the ESA, EPA is
enhancing and will continue to improve documentation and communication
of assessment results as they relate to listed species in OPP-related
risk assessment and management decisions.  This will be accomplished by
implementing processes to ensure consistency, timeliness, and
efficiency.  Such documentation will extend beyond the initial screening
level risk assessment efforts and will incorporate a transparent
discussion of any changes to the assessment assumptions, data used for
risk analyses, and the scientific, risk-based, rationale for any
mitigation measures in risk management decisions related to listed and
non-listed species.

IV.  Overview and Organization of the Environmental Fate and Effects
Division tc \l1 "IV.  Overview and Organization of the Environmental
Fate and Effects Division

EFED performs the following specific functions:

Designs and reviews protocols for environmental data collection.  Works
cooperatively with other government or private entities to gather
environmental measurement data;

Reviews, evaluates, and validates data submitted under FIFRA or provided
from other    sources on the properties and effects of pesticides.
Although EFED primarily reviews information on the active ingredient,
data on formulations and degradates are also considered when available
to the Agency;

Assesses and characterizes ecological risk from varying pesticide
scenarios in a screening-level assessment, which includes the
consideration of listed species.  The assessment addresses (1) fate and
transport of pesticides in water, soil, and other environmental media;
(2) toxicity to wildlife and vegetation; (3) exposure to non-target
vegetation, aquatic life, birds, and other wildlife; and (4) effects on
listed species.  EFED also conducts a more refined assessment on a
case-by-case basis.

Assesses and characterizes pesticide residues in drinking water used for
human consumption;

Develops and maintains specific types of databases, such as the
Ecological Incident Information System, and others; and

Develops and advances methods and tools for environmental fate,
ecological risk and    drinking water assessments.

In conjunction with HED, EFED supports OPP’s risk management
divisions, RD and SRRD, in the overall risk assessment of pesticides.
EFED also provides scientific expertise to other Agency programs and
Federal agencies on the environmental fate and effects of pesticides and
their exposure in various environmental media. In addition, EFED
provides the underlying basis for the FEAD risk assessment (Biological
Evaluation), which evaluates the potential impact on particular listed
species as well as identifies where the risk criteria for listed species
have been exceeded at the screening level.

EFED is composed of five Environmental Risk Branches (ERB I - V), the
Immediate Office (IO), and the EFED Information Support Branch (EISB).
The IO includes the Division Director and the Associate Division
Director who manage the division.  Staff in the IO consists of
administrative support personnel, two senior scientists, and a
communications officer who  provide guidance and oversight on key
division projects, implement the communication strategy for the
division, and handle key administrative functions.

EISB supports the division in the areas of additional administrative
services, filing and document storage, database development and
management, contract management, and tracking chemical actions.  The
EISB consists of administrative support staff, contract specialists,
computer experts, and scientists.

ERB-I through V are responsible for risk assessment functions described
earlier.  These branches are composed of biologists, statisticians,
chemists, environmental engineers and scientists, agronomists, and
hydrologists, predominately with Masters of Science and Doctorate
degrees.

To introduce new employees to the risk assessment processes and to keep
current scientists up-to-date, EFED holds training sessions and
workshops.  New employees are trained by providing them with documents
related to the risk assessment processes, including the Support
Documents provided to the Services.   Formal presentations may also be
held, which include topics such as an overview of OPP and the division
and the ecological risk assessment process.  Presentations on the
assessment process may include providing an overview of the assessment
process, the derivation of risk quotients, and risk assessment
methodology refinements; fate and transport; spray drift; and water
resources.

For longer tenured employees, workshops and training sessions are held
to keep scientists up-to-date.  For example, EFED held a workshop
recently on aquatic exposure models used in the European Union to
estimate pesticide concentrations in ground and surface water for use in
risk assessments supporting pesticide registration decisions.  The
purpose of the workshop was to provide new information, examine a new
tool that could be used to meet EFED’s modeling needs, and think about
how these models or a similar approach might be applied to meet modeling
needs.  Similar training sessions have included the use of statistics,
computer software training, and other topics.

A.  The Environmental Fate and Effects Division’s Procedures tc \l2
"A.  The Environmental Fate and Effects Division’s Procedures

EFED scientists review and evaluate studies submitted in support of
registration/reregistration of pesticides to determine if they are
acceptable under FIFRA guidelines. This determination is based on the
design and conduct of the experiment from which the data were derived,
and an evaluation of whether the data submitted fulfill Agency
requirements. In evaluating experimental design, the scientists consider
methods generally recognized by the scientific community, the numbers of
measurements made, and the use of controls in all phases of the
experiment. They evaluate the conduct of each experiment in terms of
whether the study was conducted in conformance with the design, good
laboratory practices were observed, and results were reproducible. The
scientists' review of a study is documented in a Data Evaluation Record
(DER), which provides a summary review of the scientific study.

A template provides guidance for EPA scientists on how to complete a
DER.  Working with the Pest Management Regulatory Agency (PMRA) of
Canada, EPA has developed 18 individual DER templates for the review of
ecological effects and fate studies.  Scientists use these templates to
review and determine, on a case-by-case basis, whether each study is
scientifically sound and provides sufficient information to satisfy
applicable data requirements

In the DER, a study is categorized as to its usefulness in a risk
assessment.  While different terms have been used over the years to
describe the quality and value of environmental fate and ecological
effects studies, there is consistency in the general meaning of the
classifications and their application.  The three general categories
used for classifying scientific studies are (1) Core or Acceptable, (2)
Supplemental, Upgradable, or Ancillary, and (3) Invalid or Unacceptable.
 (For a more detailed discussion, see Support Document #1.)

Studies are generally evaluated by contractors, who generate DERs under
formats specified by EFED.  The contractor DERs are reviewed by EFED
staff scientists assigned to the pesticide assessment in order to
finalize the data review. The branch Work Assignment Manager (WAM)
oversees the contractor’s performance, and QA/QC procedures are
included in the contractor’s statement of work. The branch WAM
contacts the contractor if there are any problems with the review or if
the review process needs to be changed.

After DERs for individual studies are developed, EFED scientists
develop the exposure and effects characterizations and the risk
characterization. These assessments are produced by an interdisciplinary
team of scientists and are combined into an integrated science chapter
which describes the potential impact of a pesticide on non-target
organisms and the environment. Science chapters are sent to either SRRD
or RD.  Drinking water exposure assessments are sent to HED for
incorporation into the human health risk assessments.

B.  Data Requirements and Other Data Sources tc \l2 "B.  Data
Requirements and Other Data Sources

As discussed previously, OPP has the authority, under FIFRA, to require
data in support of the registration of a pesticide product.
Accordingly, OPP has developed regulations (40 CFR Part 158)  which
specify the types and amount of information that pesticide companies
must routinely submit to EPA to support the registration of pesticide
products. Section 158.290 describes the environmental fate data
requirements, Section 158.490 describes the wildlife and aquatic
organisms data requirements, Section 158.540 describes the plant
protection data requirements, and Section 158.590 describes the
nontarget insect data requirements.

The data requirements are grouped according to general use pattern(s)
and are listed as either required (R) or conditionally required (CR). In
most cases, the data listed in Part 158 are sufficient to allow EPA to
evaluate a pesticide application. In those cases where the data are not
sufficient, EPA can impose additional data requirements. These data
requirements may be revised from time to time to reflect statutory
changes, policy changes and new technology.  The current data
requirements are identified in Support Document #29.

Over the course of conducting a risk assessment, the assessors may note
data gaps or identify studies which do not completely satisfy the core
elements for a particular requirement.  In such cases, the risk assessor
will evaluate whether requiring the study (or the repetition of the
study when existing data are not completely satisfactory) would be
likely to materially alter the conclusions of the risk assessment.  This
evaluation considers the nature of the use site for the pesticide, the
types of effects already observed from available acceptable data, and
the present conclusions of the risk assessment.

In the case of registration, risk managers are informed early on of
major data gaps to provide them the opportunity to contact the applicant
and obtain the data. For reregistration, risk managers hold a meeting
with pesticide registrants early in the process to provide them the
opportunity to identify the uses they will support.  This meeting
provides the risk assessor the opportunity to identify any major data
gaps based on an overview of the available data.

If some data are available, then the assessment can be conducted and
uncertainties and assumptions can be identified.  If the assessor
concludes that an additional study will not likely alter the present
conclusions of the risk assessment, they would indicate the data
deficiency to the risk manager and recommend that the study be held in
reserve for reconsideration of its necessity, should future
registrations be considered for the pesticide.  The term “reserve”
is used in its literal sense as meaning something set aside for a
special purpose.  Should a new use scenario in the future be considered
for registration that would likely render the missing information
critical to completion of a new risk assessment, then the data
requirement could be reconsidered by the risk managers.

If a risk assessor concludes that a particular study has the potential
to alter the conclusions of the risk assessment, and the risk manager
believes that such potential creates an uncertainty regarding the
confidence in making a regulatory decision, an interim decision may be
made by the risk manager to grant a registration on the condition of the
completion of an acceptable study.

Other data sources, such as open literature, can also be used in
developing the risk assessment.  Since this information is typically not
collected using the EPA’s test guidelines, it is normally considered
supplemental information.

C.  Processes to Support Sound Science tc \l2 "C.  Processes to Support
Sound Science

Sound scientific assessments are essential and serve as the foundation
for regulatory decision-making in OPP. In order to advance the quality
and consistency of EPA’s ecological risk assessments, the Agency
developed guidance for improving the ecological assessment process, risk
characterization, and peer review process.  EFED follows the Agency
guidance and has also developed associated and complementary processes
for promoting sound scientific assessments specific to pesticide
regulatory decision-making.

1.  Agency Guidance tc \l3 "1.  Agency Guidance

a.  Guidelines for Ecological Risk Assessments tc \l4 "a.  Guidelines
for Ecological Risk Assessments

The  Agency’s Guidelines for Ecological Risk Assessments (Agency
Guidelines, Support Document #7) were issued to advance the quality and
consistency of EPA's ecological risk assessments. As a next step in a
continuing process of ecological risk guidance development, the
guidelines draw from a wide range of source documents including
peer-reviewed issue papers and case studies previously developed by
EPA's Risk Assessment Forum. EFED has been and will be continuing to
advance its assessment processes, using the Agency Guidelines.  This
includes advancements to all three phases of the assessment process,
including problem formulation, analysis, and risk characterization.

b.  Risk Characterization Handbook tc \l4 "b.  Risk Characterization
Handbook

The Risk Characterization Handbook (Support Document #28) states the
Agency’s risk characterization policy.  It provides a single,
centralized body of risk characterization implementation guidance for
Agency risk assessors and risk managers and calls for a transparent
process and products that are clear, consistent, and reasonable.

The Handbook includes two parts.  The first is the risk characterization
guide, which describes the goals and principles of risk
characterization, the importance of planning and scoping for a risk
assessment, the essential elements to address in a risk
characterization, the factors considered in decision-making by risk
managers, and the forms the risk characterization takes for different
audiences.  The second part consists of appendices which contain the
Agency’s Risk Characterization Policy and case studies.

c.  Peer Review Handbook tc \l4 "c.  Peer Review Handbook

The Agency’s Peer Review Handbook (Support Document #30) was issued in
1998 as a single, centralized form of implementation guidance for Agency
staff and manager.  This Handbook builds on an active tradition of peer
review at EPA and reflects the Agency’s long-standing commitment to
peer review.

EFED has actively participated in the peer review process, which is
discussed in more detail later in this Section (IV.C.3).  The Handbook
has served as an important guide and has helped to ensure that OPP
decisions regarding ecological risk are fully supported by sound and
credible science.

2. Tools to Promote Sound Science tc \l3 "2. Tools to Promote Sound
Science

EFED uses a variety of tools to ensure that the work performed meets the
necessary level of quality and includes, but is not limited to, the
following elements: Pesticide Assessment Guidelines, Standard Evaluation
Procedures, the development and expansion of scientific databases, and
Technology Teams.

a.  Pesticide Assessment Guidelines tc \l4 "a.  Pesticide Assessment
Guidelines

EFED has developed Pesticide Assessment Guidelines which provide the
performance requirements and testing and reporting procedures for data
required (Support Document #29) in support of
registration/reregistration of a pesticide.  The guidelines describe
what data are required, test standards that should be considered in
conducting the studies, specific reporting guidance for the tests, and
examples of acceptable protocols, references and other aides to help
with planning and conducting the tests.  They include Subdivision E,
Hazard Evaluation: Wildlife and Aquatic Organisms;  Subdivision J,
Hazard Evaluation: Non-target Plants; Subdivision L, Hazard Evaluation:
Nontarget Insects; and Subdivision N, Chemistry: Environmental Fate
(Support Documents #2, #3, #4, #5, respectively.)

b.  Standard Evaluation Procedures tc \l4 "b.  Standard Evaluation
Procedures

EFED has developed Standard Evaluation Procedures (SEPs) or guidance
documents (Support Documents #8, #34 - #63) for each type of
environmental test that is generally required to support the
registration/reregistration of pesticides. EFED has also developed SEPs
which describe the Agency's pesticide ecological risk assessment
methods. These documents, which have been designed to ensure
comprehensive and consistent scientific review of data, explain the
scientific procedures used by EFED to evaluate environmental fate and
effects data submitted to  OPP.  Revisions to the SEPs or proposals for
new SEPs are discussed and developed within the six EFED Technology
Teams, followed by review and approval by the Science Policy Panel.
After internal approval by the Science Policy Panel and division
management, the SEPs are reviewed by an external science peer review
group, such as the Scientific Advisory Panel.  (The Technology Teams,
Science Policy Panel and Scientific Advisory Panel are discussed in more
detail later in this Section [IV.C.2.d, IV.C.3.c, and IV.C.4,
respectively)

c.  Databases tc \l4 "c.  Databases

EFED continues to develop, advance, and expand its databases and
information systems to support a sound scientific process.  These
include the Ecotoxicity Database, Ecological Incident Information
System, and Environmental Fate Database along with databases that
address ground and surface water.  In addition, EFED also uses EPA’S
ECOTOX, a comprehensive  tool for locating chemical toxicity data for
aquatic life, terrestrial plants and wildlife.  (See Section V.B.2.b.
for further discussion.)

OPP’s Ecotoxicity Database - Over the last 30 years, pesticide
manufacturers have submitted thousands of ecotoxicity studies to support
the registration or reregistration of their pesticide products.
Ecotoxicity studies measure the effects of chemicals on fish, wildlife,
plants, and other wild organisms.   EFED reviewed these studies
according to criteria outlined in the Standard Evaluation Procedure
Manuals and testing methods accepted by the scientific community. After
reviewing these studies, EFED scientists  determined if they were
acceptable for use in the regulatory process.  These data are used,
along with consideration of other publically available effects data, in
establishing the effects endpoints for screening-level risk assessments.
(See Section V.B.2.b.)

In 1991, EFED began electronically summarizing acceptable studies and
has now entered over 15,000 summary records for about 680 pesticide
active ingredients into a computerized database called the Pesticide
Ecotoxicity Database.  These summary records include endpoint
measurements such as the LD50 (the amount or dose of a chemical which
kills 50% of the exposed animals) and the NOEL or No Observed Effect
Level (the highest concentration of a chemical in a toxicity test that
has no significant adverse effect on the exposed population of test
animals).  Although most of the toxicity information in this database
was compiled from studies conducted by commercial laboratories, the
database also contains acceptable studies, which meet the Agency’s
testing requirements, conducted by EPA; U.S. Department of Agriculture;
and the U.S. Geological Survey (the former U.S. Fish and Wildlife
Service).  Further information is also available in Support Document
#32.

Ecological Incident Information System - In 1992, the Agency created a
database called The Ecological Incident Information System (EIIS) to
store information extracted from incident reports.  (Documentation is
provided in Support Document #22.)  The two primary sources of incident
reports are pesticide registrants and government agencies.  Under
Section 6(a)(2) of FIFRA, pesticide manufacturers are required to report
to EPA any information related to known adverse effects to the
environment caused by their registered pesticides.

The second major source of information is investigative reports which
are voluntarily submitted to the Agency from state and other federal
agencies that oversee agriculture, wildlife, natural resources, and
environmental quality. Diagnostic reports are also obtained from the
National Wildlife Health Institute (U.S. Geological Survey), the
Patuxent Wildlife Research Center (U.S. Geological Survey), the
Southwest Wildlife Cooperative Disease Study, and state wildlife
forensic laboratories. In addition, information is also extracted from
accounts of ecological incidents reported in newspapers and reliable
internet sources.

Information included in EIIS includes the date and location of the
incident, the type of adverse effects observed, the number of animals
affected by species, and the identity of the pesticide or pesticides to
which the incident was attributed.  When available, further details may
be entered about the rate and method of pesticide applications, legality
of the pesticide use, weather conditions, and results of any chemical
residue and cholinesterase activity analyses conducted during the
incident investigation.  Often insufficient information is available to
confirm the cause of incidents with certainty.  For each pesticide
identified in the incident report, an EPA employee assigns a certainty
index value to reflect the level of certainty that the specific
pesticide caused the observed effects.  The certainty index is set to
highly probable, probable, possible, unlikely, or unrelated based on
results of residue analysis and other evidence of cause.  The certainty
index is always reported along with the other incident data and should
be carefully considered when interpreting incidents.

Environmental Fate Database - OPP collects and reviews a variety of
environmental fate studies submitted by pesticide manufacturers in
support of the registration and reregistration review of pesticide
products.  After reviewing the data in these studies, OPP scientists
summarize the information in DERs, REDs, and other reports.

In 2000, OPP initiated the development of a pesticide environmental
fate database which will allow the user to search and view the data,
query the fate database, and print reports that are found in these
summary reports.  OPP plans to complete the initial version of this
database by the end of 2004.

d.  Technology Teams tc \l4 "d.  Technology Teams

EFED has six Technology Teams (Tech Teams), which are organized by
scientific disciplines and meet on a regular basis to promote sound
science and work on technical issues within the Division. They include
the Fate and Transport Team, Aquatic Biology Team, Plant Biology Team,
Terrestrial Exposure Assessment Team, and Water Quality and Exposure
Assessment Team.  The purpose of these teams is to:

Facilitate scientific consistency within disciplines, which includes
consistency in data review, use of data in assessments, application of
statistics and modeling, and use of assessment processes and tools;

Provide a forum to keep up with scientific advances and to facilitate
interaction between scientists with similar background or common
scientific interest;

Resolution of technical issues, resulting in new scientific guidance and
procedures; and

Provide a resource of information and guidance for scientific issues and
new ideas.

Once a technical issue has been resolved, a policy is in place which
outlines the basic steps for reviewing and approving new science
guidance and procedures (Support Document #64).  The length of time for
implementation will vary, depending on the issues raised and whether
external peer review is needed. However, provisions have been made to
implement guidance and procedures which need an expedited review and
approval.  It should be noted that special project teams are also
required to use the same procedures.

3. Internal Peer Review Mechanisms tc \l3 "3. Internal Peer Review
Mechanisms

a.  Data Evaluation Records tc \l4 "a.  Data Evaluation Records

All DERs are peer reviewed internally at the branch level by another
EFED scientist with the appropriate expertise. After the branch-level
peer reviewer approves and finalizes the DER, copies are sent to the
EFED Tracking Team who forwards it to the appropriate risk management
division.

b.  Risk Assessments and Risk Characterizations tc \l4 "b.  Risk
Assessments and Risk Characterizations

All risk assessments and risk characterizations are reviewed within a
task team consisting of scientists from different disciplines. After the
team reviews these documents, they are peer reviewed within the branch
or in another EFED branch by a scientist with appropriate expertise.

Following branch-level review, divisional peer review is conducted by
the Risk Assessment and Risk Characterization Review Panel (Review
Panel) which consists of interdisciplinary scientists who peer review
all major risk assessments and risk characterizations for new chemicals
and for reregistration actions. This Panel is an important internal peer
review mechanism and is composed of senior scientists in the division.
In addition, FEAD scientists participate and provide technical comments
on the assessment process in general and as it relates to listed
species.  After panel members have reviewed a specific risk assessment,
they meet with scientists, provide feedback, and ask questions
concerning the assessment.

c.  Science Policy Panel tc \l4 "c.  Science Policy Panel

The Science Policy Panel is comprised of five experienced, highly
qualified experts in the environmental and ecological risk assessment of
pesticides.  They are responsible for providing assistance to Tech Teams
in policy problem formulation, review of proposed science policies for
consistency and quality, and in developing implementation and
communication plans for new policies.  They are also responsible for
participating in the EFED budget process and making recommendations
regarding new projects and establishing priorities.

4.  External Peer Review and Scientific Advisory Panel tc \l3 "4.
External Peer Review and Scientific Advisory Panel

All significant new science guidance and procedures as well as tools and
methodologies  are reviewed by the FIFRA Scientific Advisory Panel
(SAP), EPA’s peer review body for current scientific issues related to
pesticides.  It is comprised of nationally and internationally
recognized scientific experts in toxicology, pathology, environmental
biology, and related sciences; and members are appointed by the
Administrator.

For example, the FIFRA SAP has peer reviewed the new tools and
methodologies OPP has been developing in its initiative to refine the
ecological assessment process for pesticides.  This initiative, which
began in 1997, was in response to recommendations from a meeting with
the SAP in 1996 and built upon previous efforts in the Division.
Throughout the development of this initiative, OPP has returned to the
SAP several times to seek comments and recommendations on the progress
being made.  In some cases, EFED has sought guidance from the SAP on
problematic issues and questions before proceeding further.  Input from
the SAP  early in the development of tools and methods is critical to
their successful implementation in the risk assessment process.

V.  Overview of OPP’s Screening-Level Ecological Risk Assessment
Process for Aquatic

       Life, Wildlife, and Plants tc \l1 "V.  Overview of OPP’s
Screening-Level Ecological Risk Assessment Process for Aquatic
Life, Wildlife, and Plants

This section provides an overview of the screening-level assessment
process to evaluate the potential impact of pesticides on non-target
organisms.  (Section VI provides an overview of the species-specific
assessment.)  As previously mentioned, this process is consistent with
the Agency’s Guidelines for Ecological Risk Assessment (Support
Document #7).   Although this section reviews the general assessment
process for screening-level assessments, this assessment process may, on
a case-by-case basis, incorporate additional methods, models and lines
of evidence that EPA finds technically appropriate for specific risk
management objectives.

The majority of screening-level assessments are conducted in EFED for
conventional pesticides.  However, some screening-level assessments are
also conducted in AD and BPPD for non-conventional pesticides.  The
ecological assessments conducted by AD and the microbial assessments
conducted by BPPD are largely based on the process described in this
section. However, BPPD also conducts assessments for biochemicals,
which, because of their unique nature, do not typically follow the same
procedures and are more qualitative in nature.  The assessment processes
conducted by AD and BPPD are described in Appendices A and B,
respectively.

A.  Problem Formulation tc \l2 "A.  Problem Formulation

Before the risk assessment process begins, risk assessors and risk
managers discuss (1) the potential value of conducting a risk
assessment, (2) goals for ecological resources, (3) range of management
options, (4) objectives of the risk assessment, (5) the focus, scope and
timing of the assessment, and (5) resource availability. The
characteristics of an ecological risk assessment are directly determined
by agreements reached by risk managers and risk assessors during early
planning meetings.  In addition to discussions between risk assessors
and risk managers, information provided by the pesticide registrants is
also taken into consideration when developing the problem formulation.
It should be noted that the problem formulation will document, when
necessary, any aspects of the analysis that extend beyond the initial
screening level risk assessment efforts.  The problem formulation will
allow for an analysis of any changes in risk estimates based on
different assessment assumptions, including those that may be related to
proposed mitigation options, and data used for risk analyses.

1.  Defining the Regulatory Action tc \l3 "1.  Defining the Regulatory
Action

Prior to initiation of the risk assessment process, risk managers
communicate the nature of the regulatory action to the risk assessors.
For risk assessment activities supporting REDs, these communications are
initiated with personnel from SRRD.  For regulatory actions involving
new pesticide active ingredients or new uses of active ingredients with
existing registrations (FIFRA Section 3 actions), emergency exemptions
(FIFRA Section 18 actions), and special local needs uses (FIFRA Section
24c actions), the regulatory communications are initiated with personnel
from RD.

During this problem formulation phase, risk assessors and risk managers
consider the following questions:

What is the regulatory basis for the requested action under FIFRA?  How
does this action affect the temporal and geographic scope of the impact
area of the risk assessment?

What are the management goals and regulatory issues?  How will the risk
assessment clarify decisions concerning risk management options?

Are there any policy considerations that everyone should be aware of?

What precedents are set by similar risk assessments and previous
decisions?

2. The Nature of the Chemical Stressor Considered in the Risk Assessment
tc \l3 "2. The Nature of the Chemical Stressor Considered in the Risk
Assessment

The Agency routinely incorporates measures of exposure and effects for
the pesticide active ingredient in the risk assessment process for all
regulatory decisions.  Additionally, EPA examines available formulated
product information, environmental fate data, and toxicological data to
determine the need to expand beyond the focus on the active ingredient
to consider pesticide formulations, inert ingredients, or degradates of
the active ingredient in a particular risk assessment to support
registration of a specific pesticide product.  Available formulated
product information, environmental fate data, and toxicological data may
come from a number of sources.  These include section 6(a)(2) data, open
literature data retrieved through ECOTOX (see Section V.B.2.b), and
direct submissions in support of registration.  The methods for
incorporating environmental fate and effects data for formulations and
active ingredient degradates into the risk assessment processes are
described in Section V.B. 1 and 2, in which exposure and effects are
discussed.

The Agency is currently developing procedures for assessing toxicity and
risks associated with inert ingredients and surfactants in formulations
(See Support Document #24) and will perform either qualitative or
quantitative assessments of potential risk associated with these
chemicals.  The decision to perform either type of assessment is based
on available information on the chemical characteristics of the inert
ingredient and any information on the inert ingredient’s toxicological
characteristics.  Information on an inert ingredient’s toxicological
characteristics may include available ecological effects information
from the literature, or information on closely related chemical
analogues and quantitative structure-activity relationships.  Use of
structural analogy or structure activity models is consistent with
techniques employed in other Agency programs (e.g., the approach used by
OPPT in evaluating new chemicals in commerce through the
Premanufacturing Notification process).  This information is used to
determine if inert ingredients can be classified as (1) generally
recognized as safe, (2) available data are insufficient to confirm
little or no toxicity and would require additional study, or (3) there
is sufficient toxicological and exposure concern to warrant a
quantitative risk assessment similar to those conducted for active
ingredients.

It is important to note that existing and vetted quantitative
structure-activity relationships have focused on industrial chemicals,
the types of compounds commonly found as inert ingredients and
surfactants in pesticide formulations.  Establishing these relationships
has been facilitated by the non-specific modes of toxic action of these
compounds and are typically based on simple correlations between their
acute potency to aquatic organisms as measured by lethality (e.g., LC50
values) and basic physical/chemical properties of the compounds.
Application of quantitative structure activity relationships developed
for industrial chemicals to predict effects for pesticide active
ingredients is not scientifically defensible due to their different, and
highly specific, modes of toxic action for these active ingredients when
compared to industrial, organic chemicals.

The Agency does not routinely include, in its screening risk
assessments, an evaluation of mixtures of active ingredients, either
those mixtures of multiple active ingredients in product formulations or
those in the applicator’s tank.  In the case of the product
formulations of active ingredients, each active ingredient is subject to
an individual risk assessment for regulatory decision regarding the
active ingredient on a particular use site.  If effects data are
available for a formulated product, it is documented in the risk
assessment and the quantitative or qualitative use of such formulation
information follows procedures outlined in the discussion on exposure
and effects characterization.

In accordance with risk assessment guidance, the Agency documents the
scope of the chemical stressors considered in the risk assessment, the
rationale for their consideration, the methods used to evaluate the
attendant risks, and their contribution to the overall conclusions of
the risk assessment.

3.  Pesticide Use Characterization tc \l3 "3.  Pesticide Use
Characterization

For each regulatory action, product labeling provides information on the
proposed and/or existing uses of the pesticide product.  The pesticide
labeling is the legal document that provides the user with instructions
for use, use restrictions, and hazard statements  (see Support Documents
#67 and #68).  Risk assessors use the information on the product
labeling to define the nature of the pesticide use in the field.  Use
factors on the labeling are important for determining input parameters
for exposure models and the magnitude of exposure to non-target
organisms, including geographic locations most likely to be exposed.
Labeling information crucial to ecological assessments include:

Type of formulation, such as bait, granule, wettable powder,
emulsifiable concentrate, etc.;

Product purity, which is the proportion of that product that is the
pesticide active ingredient;

Proposed and/or existing application rates;

Treated crop(s) and, if specified, target pest(s);

Geographic limitations of use, if any;

Application methods, such as aerial, ground, foliar, soil surface, soil
incorporated, etc.;

Application timing, such as season and time of day;

Frequency of application, application intervals, and maximum number of
applications per season; and

Hazard advisory statements: protective measure for wildlife/aquatic
habitats, groundwater, etc.

In addition to the information on the label, scientists consult with
BEAD and the registrant for information on the following topics:

Nature of the target pests,

Geographical distribution of the pests, crop, and market of the
pesticide,

Temporal pattern of the pesticide’s use, and

Any unique aspects of the use of the pesticide under field conditions.

The characterization of pesticide use allows the risk assessors and risk
managers to focus the risk assessment on specific use patterns that are
representative of a larger variety of use patterns.  Such groupings may
consider the types of agricultural scenarios, the methods for pesticide
application, and commonality of applications rates and timing.  In this
way, modeling and assessment resources can be concentrated on scenarios
that reasonably represent the highest exposures among a suite of use
scenarios.

4.  Identification of Assessment Endpoints tc \l3 "4.  Identification
of Assessment Endpoints

The Agency Guidelines define assessment endpoints as “explicit
expressions of the actual environmental value that is to be protected”
which are “operationally defined by an ecological entity and its
attributes” (Support Document #7). The ecological entity can be a
species, a functional group of species, a community, an ecosystem, or
another entity of importance or concern.  An attribute is the
characteristic of the entity that is important to protect and is
potentially at risk.

The selection of clearly defined assessment endpoints is important
because they provide direction and boundaries in the risk assessment for
addressing risk management issues of concern. Each assessment endpoint
needs one or more “measures of effect,” which are changes in the
attributes of an assessment endpoint itself or changes in a surrogate
entity or attribute in response to exposure to a pesticide.

a.  Direct Effects tc \l4 "a.  Direct Effects

The typical assessment endpoints for screening-level pesticide
ecological risk assessments are reduced survival and reproductive
impairment for both aquatic and terrestrial animal species from both
direct acute and direct chronic exposures. These assessment endpoints,
while measured at the individual level, provide insight about risks at
higher levels of biological organization (e.g., populations).  Hallam
and Lassiter (1994) assert that toxicants do not affect populations or
communities except through the impact on the individuals comprising the
population or community and the demographics of  birth, growth, and
death that govern population dynamics. Similarly, Tanner (1978)
indicates that the number of individuals within a population change
(intrinsic rate of increase) primarily because of births (fecundity) and
deaths (survival) and secondarily from migration in and out of a
specific area.  Investigations by Hakoyama et al. (2000) concerning risk
factors of wildlife population extinctions suggest that toxicant effects
on individual survivorship have important implications for both
population rates of increase and habitat carrying capacity.  If effects
on the survival and reproduction of individuals are limited, it is
assumed that risks at the population level from such effects will be of
minor consequence. However, as the risk of reductions in survival and/or
reproduction rates increase, the greater the potential risk to
populations.

For terrestrial plants, the screening assessments are concerned with
perpetuation of populations of non-target species (crops and non-crop
plant species).  Existing testing requirements have the capacity to
evaluate emergence of seedlings as well as vegetative vigor. Although it
is recognized that the endpoints of seedling emergence and vegetative
vigor may not address all terrestrial plant life cycle components, it is
assumed that impacts at emergence and in the active growth stages have
the potential to impact individual competitive ability and reproductive
success.

For aquatic plants, the assessment is concerned with the maintenance and
growth of standing crop or biomass.  Measurement endpoints for this
assessment focus on algal growth rates and biomass measurements as well
as similar measurements for vascular plants.

b.  Indirect Effects for Listed Species tc \l4 "b.  Indirect Effects for
Listed Species

Screening-level assessments of indirect effects for listed species are
discussed in Sections B.2.c and C.4  of this chapter.  Species-specific
assessments for indirect effects on listed species are developed, when
required, after the screening-level evaluation is completed. (See
Section VI for further discussion.)

c.  Effects on Listed Species Critical Habitat tc \l4 "c.  Effects on
Listed Species Critical Habitat

Screening-level assessments of effects upon critical habitat for listed
species are discussed in Sections B.2.d and C.5 of this chapter.
Species-specific assessments for critical habitat of listed species are
developed, when required, after the screening-level evaluation is
completed.  (See Chapter VI for further discussion.)

5.  Measures of Effects and Exposure: The Use of Surrogate Organisms tc
\l3 "5.  Measures of Effects and Exposure: The Use of Surrogate
Organisms

Rarely are toxicity data available for the species identified in the
risk assessment endpoints.  In the majority of cases, the
screening-level risk assessment process relies on a suite of toxicity
studies performed on a limited number of organisms in the following
broad groupings:

Birds (mallard duck and bobwhite quail) used as surrogate for
terrestrial-phase amphibians and reptiles,

Mammals (laboratory rat),

Freshwater fish (bluegill sunfish, rainbow trout, and fathead minnow)
used as a surrogate for aquatic phase amphibians,

Freshwater invertebrates (Daphnia magna),

Estuarine/marine fish (sheepshead minnow),

Estuarine/marine invertebrates (Crassostrea virginica and Mysidopsis
bahia),

Terrestrial plants (corn, soybean, carrot (radish or sugar beet), oat
(wheat or ryegrass), tomato, onion, cabbage (cauliflower or brussels
sprout), lettuce, cucumber), and

Algae and aquatic plants (Lemna gibba, Skeletonema costatum, Anabaena
flos-aquae, Selenastrum capricornutum, Clorell vulgaris, Scenedesmus
subspicatus)

Within each of these very broad taxonomic groups, an acute and a chronic
endpoint are selected from the available test data.  The selection is
made from the most sensitive species tested within that organism group.
If additional toxicity data for more species of organisms in a
particular group are available, the selection need not be limited to the
species listed above, but may be expanded to include data for other
species/studies that meet the data quality classification of
“supplemental.”  (See Support Document #1 for discussion of the data
classification scheme.)  Available scientific information from alternate
sources (e.g. searches conducted using the ECOTOX database described in
Section V.B.2.b.1) is also examined for species within a taxonomic group
for which other taxa are typically used as surrogates. For example, fish
data are commonly used to evaluate impacts to amphibians.  But, if
toxicity data are available in the open literature on amphibians, these
data may be used instead of the data on the surrogate species.  In
situations where such additional data are available, decisions are made
regarding the quality and utility of such information in the risk
assessment (e.g., a review of the validity and reliability of study
protocols), which is consistent with the Agency’s risk assessment
guidance.  The extent to which such additional data are either employed
or rejected is described through a transparent, concise discussion.
Regardless of the extent of data beyond the regulation-required set of
toxicity studies, the risk assessment relies on selection of endpoints
from the most sensitive species tested in acceptable studies.

Exposures estimated in the screening-level risk assessment for
non-target organisms are likewise not specific to a given species.
Aquatic organism (plant and animals) exposures are based on a set of
standardized water body assumptions (water body size, watershed size,
proximity to field, etc.) that result in high-end estimates of exposure
(see Section V.B.1.b).  Estimates of exposure for terrestrial birds and
mammals assume that animals are in the treatment area, and exposure
estimates involve grouping taxa based on food preferences (e.g.,
obligate insectivores, herbivores, granivores) and generic weight
classes.  Exposure for terrestrial plants considers surface runoff from
treated fields as well as direct application via pesticide spray drift.

6.  Identification of Data Gaps tc \l3 "6.  Identification of Data Gaps

When a data package is received for a registration of a new active
ingredient or a new use, the submissions are reviewed to ensure that the
environmental fate and ecological effects data sets are complete for the
proposed pesticide use.  For actions in which a database for the active
ingredient is already available (i.e., reregistration, new uses of
existing active ingredients, Section 18s, etc.), the risk assessor
reviews the adequacy of existing and new submissions and previous
assessments.  In either case, whenever possible, data gaps are noted
early on in the risk assessment process and communicated to the risk
manager as discussed in Section IV.B.  Data gaps are addressed as a
source of uncertainty in the risk assessment conclusions, and the risk
assessment discusses the potential for additional data to affect the
risk assessment conclusions.  In the absence of data, adverse effects
may be assumed to occur until a study is submitted to indicate
otherwise.

Once data gaps in the ecological effects and environmental fate
databases are identified, the risk assessment team must determine
whether it is possible to perform the risk assessment.  A
screening-level ecological risk assessment is possible when the data
submitted on ecological effects and environmental fate of the pesticide
are scientifically valid and complete based on the Agency’s review
criteria in the Standard Evaluation Procedures (see Support Documents
#35 - #63).   Studies for effects are classified in one of three
categories:  core, supplemental, and invalid.   Core data are from
studies found to be scientifically valid and conducted consistent with
Agency testing guidelines.  Supplemental data are from studies found to
be scientifically valid but do not follow all requirements set forth in
Agency testing guidelines.  Invalid data are from scientifically unsound
studies.  Similar classifications of data are set forth for
environmental fate studies.

In some instances, a core study may not be available for a particular
data requirement listed in 40 CFR 158. In this case, the risk assessment
team may consider other sources of information to address the data gap
(e.g., submitted studies considered to be supplemental and data from
other sources not submitted as part of fulfillment of 40 CFR 158).  If
supplemental or non-guideline study data are available to address the
type of information described by the associated guideline, then it may
be used in the risk assessment after its use is carefully considered.
Professional judgment is used by the risk assessment team to determine
the utility of the available supplemental data for the proposed risk
assessment.  This latter evaluation may include reference to data
quality objectives for specific types of studies, the degree to which
adequate documentation is available to evaluate the technical merit of
the data, and whether the data are applicable to the assessment
endpoints established for the risk assessment.  The Agency’s risk
assessment guidelines instruct risk assessors to clearly and concisely
document the evaluation of all data considered in the risk assessment.
Even if supplemental or non-guideline data are used to address a data
gap in the risk assessment, the risk assessment team will still note the
gaps in the guideline study requirements and provide the risk manager
with a determination of the potential impact of those gaps upon the
confidence of the risk assessment.

There may be other instances where there is a lack of scientifically
valid data (i.e., neither core or supplemental data are available).  In
this situation, certain aspects of the risk assessment may not be
performed.  In such situations, discussions with the risk manager ensue
to determine whether these data gaps will seriously limit regulatory
decision-making.  In the absence of data needed to make the required
findings under FIFRA, EPA cannot register or reregister a pesticide.

B.   Analysis Phase tc \l2 "B.   Analysis Phase

1.  Exposure Characterization tc \l3 "1.  Exposure Characterization

In most cases, an exposure characterization conducted in support of a
regulatory decision of a pesticide provides a quantitative analysis of
the critical environmental fate and transport properties of the
pesticide active ingredient.  However, there are situations where
formulations are of demonstrated higher toxicity than the active
ingredient alone, or where degradates occur in significant amounts or
are of significant toxicological concern.  In such situations, exposure
characterizations would include a quantitative or qualitative analysis
of the risk implications of organism exposure to these degradates or
formulations in addition to the active ingredient.  The Agency’s risk
assessment guidance instructs risk assessors to clearly and concisely
describe the nature of the stressors evaluated in the risk assessment.
This includes documentation of the potential significance of degradates
and formulations in the risk assessment of pesticides.  Section
V.B.1.a., which is found below, and materials in Support Document #78,
relating to HED’s Metabolism Assessment Review Committee (Section
V.B.2.), describe the process for including degradates in the risk
assessment.  Sections V.B.1.b.(2) and V.B.1.c.(2) discuss specific
exposure methods  for the quantitative consideration of pesticide
formulations in the risk assessment.

The quantitative expressions of the fate and transport properties, along
with the information related to the use of the pesticide active
ingredient and the physical, chemical, and biological conditions of the
use sites are used to estimate the potential exposure of plants,
wildlife, and aquatic life to pesticide residues in environmental media.
 This characterization includes information on how often, how long, and
the amount of  pesticide active ingredient and its degradates of concern
to which an organism may be exposed.  The exposure characterization is
based on environmental fate and transport data, modeling, and monitoring
information.

In order to quantitatively predict the fate and transport of a pesticide
once it is introduced into the environment, OPP scientists review
laboratory and field studies that measure how  pesticide active
ingredients interact with soils, air, sunlight, surface water, and
ground water.  These studies provide information concerning:

The degradation of the pesticide active ingredient (how fast and by what
process it is degraded in the environment) and how persistent the
pesticide active ingredient is in the environment;

The breakdown products that result from the degradation processes;

The mobility of a pesticide active ingredient or its degradates or
metabolites and how it will move from the application site; these
studies predict the potential of the pesticide to volatilize into the
atmosphere, move into ground or surface waters, or bind to the soil; and

How much of a pesticide active ingredient and its degradates or
metabolites will accumulate in the environment.

a.  Fate and Transport Data Requirements and Study Evaluation tc \l4 "a.
 Fate and Transport Data Requirements and Study Evaluation

The Agency regulations found in 40 CFR 158.290 (Support Document #29)
describe the types and amount of data the Agency commonly uses for
assessing the environmental fate of an active ingredient. These data are
generated from controlled laboratory and field studies, which are
conducted under approved Guidelines and Good Laboratory Practices.  They
are used to determine the persistence, mobility, and bioconcentration
potential of a pesticide and its major degradates in the environment.

The types of data required may vary depending on where the pesticide is
used.  Some of these studies, such as hydrolysis, photolysis, aquatic
and soil metabolism, and terrestrial dissipation, are routinely
conducted for all outdoor use pesticides.  Others are conditionally
required and are triggered by use or application patterns and basic
product chemistry data.

Controlled environmental fate and transport laboratory studies are used
to determine the persistence, mobility, and bioconcentration potential
of a pesticide active ingredient and its major degradates.  Persistence
studies assess what happens to a pesticide active when it interacts with
water, soil, air, and sunlight.  Mobility studies attempt to predict the
potential of the active ingredient to volatilize into the atmosphere,
move into ground or surface waters, or bind to soil.   Bioconcentration
studies evaluate the potential of an active ingredient to partition to
aquatic biota and the degree to which bioconcentration can be reversed
should external exposure to the active ingredient or degradates be
reduced or eliminated.  These studies are designed to help characterize
how a pesticide active ingredient dissipates once it is released into
the environment and to identify the major degradates that may result
from these processes.

Degradation studies include hydrolysis, photodegradation in water,
photodegradation in air, and photodegradation on soil.  The hydrolysis
study determines the potential of the pesticide active ingredient to
degrade from the influence of water alone.  Photodegradation studies
determine the potential of the active ingredient to degrade in water,
soil, or air when exposed to sunlight.  During these studies, data are
also collected concerning the identity, formation and persistence of
major degradates.

Metabolism studies include aerobic soil metabolism, anaerobic soil
metabolism, anaerobic aquatic metabolism, and aerobic aquatic
metabolism.  The soil microbial metabolism  studies determine the
persistence of the pesticide active ingredient when it interacts with
soil microorganisms under aerobic and anaerobic conditions.  The aquatic
metabolism studies produce similar data, but are generated by active
ingredient interaction with microorganisms in a water/sediment system.
These studies also identify the significant degradates that result from
biological degradation.

Mobility studies, which include leaching, adsorption/desorption, and
volatility, provide information on the mode of transport and eventual
destination of the pesticide active ingredient in the environment.
Scientists can predict the degree of pesticide mobility in soil from
data generated from leaching and adsorption/desorption studies.

Bioconcentration studies in aquatic organisms are used to estimate the
potential of a pesticide active ingredient, under controlled laboratory
conditions, to partition to the organisms from respiratory and dermal
exposures.  These studies also provide information on the degree to
which bioconcentration of a pesticide or degradate can be reversed
should pesticide levels in the surrounding aquatic environment be
reduced.

Field studies which identify the environmental dissipation processes,
assess the transformation, transport, and fate of pesticide active
ingredient under actual use conditions with typically applied pesticide
product at representative field sites.  These studies characterize the
relative importance of each route of dissipation of the pesticide active
ingredient and its major degradates.  Data generated from field
dissipation studies can provide more realistic estimates (albeit limited
in time and space) of the persistence and transport of an active
ingredient and its degradates when the pesticide product is applied
under actual use conditions.

Guidance for reviewing environmental fate and transport studies is
provided in Subdivision N Guidelines and the associated Standard
Evaluation Procedures (Support Documents #5, # 41 - #44, #60 - #62.).
However, OPP may also review sources of data other than those conducted
according to the Subdivision N Guidelines, such as non-guideline studies
submitted by the pesticide registrant and data published in the
scientific literature.  It is important to note that the manner in which
additional non-guideline data are incorporated into a risk assessment is
established on a case-by-case basis.  The risk assessment team uses
professional judgment in evaluating such aspects as:

The data quality objectives of the study,

Availability of documentation sufficient for evaluating the technical
merit of the methods and results analysis, and

General applicability of the results as compared to the exposure
scenarios that are considered important in the risk assessment.

The Agency recognizes the importance of using the best available science
in characterizing environmental exposure.  Non-guideline data may be
used to address data gaps in the assessment, even to the extent of
providing quantitative values for dissipation pathway inputs for
exposure modeling.  These data may even be useful for addressing fate
issues that are not specifically identified in the existing guideline
studies.  The risk assessment team must clearly and concisely document
the environmental fate information considered in the risk assessment.
Though data from non-guideline studies may be considered supplemental
information in a risk assessment, they cannot be used to satisfy
guideline requirements to support registration.

In addition to assessing the environmental fate of active ingredients,
the Agency requirements indicate that the formation of degradates be
monitored in the fate studies.  This is often accomplished through the
use of radio-labeled compound to ensure that detection limits are
sufficiently low to allow for detailed tracking of the production of
degradates.   Degradates formed at greater than or equal to 10% of the
applied radioactivity in the environmental fate studies are considered
significant (i.e., major degradates) and must be identified (see Support
Document #5).  The 10% criterion is a general guideline, meaning that
degradates approaching concentrations of 10% of the applied
radioactivity are usually identified as well.  In addition, degradates
of known toxicological or ecotoxicological concern must be quantified
and identified even when present at less than 10% of the applied
radioactivity.

In order to identify degradates of toxicological concern, environmental
fate scientists engage in discussions with human health reviewers in HED
and ecotoxicology reviewers in EFED.  (Support Document #78 provides
additional information on the process used by the Agency to identify
degradates of concern.)  In accordance with Agency risk assessment
guidance, the risk assessment team must clearly and concisely document
the rationale of including or excluding degradates from consideration in
the risk assessment.

Once the individual studies are reviewed and determined to be
appropriate for inclusion in the risk assessment, OPP relies on the
results of these studies to provide the quantitative fate and transport
inputs for ecological exposure modeling.  Selection of these input
values are specific to the exposure model being used. ( Guidance for the
selection process can be found in Support Documents #9, #17, and #18.)
The following sections (B.1.b,c,and d) discuss exposure modeling methods
available to OPP for screening-level risk assessments.

b.  Aquatic Organism Exposure Modeling tc \l3 "b.  Aquatic Organism
Exposure Modeling

(1).  General Approach tc \l5 "(1).  General Approach

For aquatic organisms, such as plants, fish, aquatic-phase amphibians,
and invertebrates, OPP generally uses computer simulation models to
estimate exposure to a pesticide active ingredient.   These models
calculate estimated environmental concentrations (EECs) in surface water
using laboratory data that describe how fast the pesticide breaks down
to other chemicals and how it moves in the environment.  Section V.B.1.b
(2) describes the Agency’s approach for exposure modeling in
situations where available information suggests that ecological risks
from formulated products should be considered.

In aquatic organism modeling, a tiered system of modeling is used to
efficiently allocate resources to assessment efforts of varying
complexities and potential risks.  The intent of the lower tiers is to
provide a screening approach to estimate the concentration of a
pesticide in water from sites that are highly vulnerable to runoff or
leaching.  OPP is confident that when a pesticide is not predicted to
cause adverse effects on the environment using EECs generated from
screening- level tiers, that the possibility of harming the environment
is low.  The assessment moves to a more refined one that is based on
conditions more reflective of actual use site conditions, when Levels of
Concern (LOCs), discussed later in this section, are exceeded using EECs
based on generic assumptions (non-use site specific).

The first screening model employed is a generic one that is not specific
to the particular use-site.  This model, GENEEC2 (GENeric Estimated
Environmental Concentration), is used to screen chemicals to determine
the ones which potentially pose sufficient risk to warrant more detailed
or refined modeling.  The GENEEC2 calculates high-end estimates of
surface water concentrations of pesticides in a generic farm pond.  The
Agency considers this scenario a high-end estimate for the following
reasons:

The input value for the application rate and number of applications is
the labeled maximum;

The entire watershed is assumed to be cropped and treated with the
pesticide, and the watershed area is high relative to the volume of the
water body;

No buffer is assumed between the pond and the treated field;

Runoff is assumed to be from a 6-inch rainfall over a 24-hour period;
and

The geographic location of use is regarded as representative of high-end
potential for pesticide runoff and is not necessarily representative of
runoff conditions for the labeled use.

GENEEC2 provides a rapid screen to separate the low risk pesticides from
those that need more refined assessments. The model estimates high level
exposure values of pesticides in surface water using the following
inputs:

Basic chemical characteristics,

Pesticide label use and application information,

Adsorption of the pesticide to soil or sediment,

Direct deposition of spray drift into the water body, and

Degradation of the pesticide in soil before runoff and within the water
body.

GENEEC2 is a single-event model, based on a single, large
rainfall/runoff event occurring on a 10-hectare field that removes a
large quantity of pesticide at one time from the field to a pond that
has a 20,000-liter water volume and is 2-meter deep. (See the GENEEC2
User's Manual and GENEEC2 Model Description for more information, which
may be obtained from the following url:
www.epa.gov/oppefed1/models/water/index.htm.)

If the LOC for risk to non-target species is not exceeded using GENEEC2
EECs, OPP is confident that there is no risk of concern.  If the LOC is
exceeded using GENEEC2 EECs, a small possibility exists, albeit
unlikely, that an extreme exposure could exceed toxicity thresholds
established in the effects characterization.  However, the risk
assessment team cannot discount the possibility that GENEEC2 model
assumptions leading to such high-end exposure predictions may not be
realistic for the labeled use of the pesticide.  In those instances
where exposure levels exceed the levels associated with the toxic
threshold, a more realistic exposure characterization is established
using a more comprehensive model (PRZM-3 and EXAMS II) and runoff
conditions more reflective of labeled use sites.

 The PRZM-3 and EXAMS II model provides more realistic, use-site
specific EEC values by refining the model inputs for pesticide transport
and transformation down through the crop root and unsaturated zone, and
runoff and spray drift loading in the farm pond.

PRZM-3 is a process or "simulation" model that calculates what happens
to a pesticide in treated fields on a day-to-day basis. It considers
factors such as rainfall and plant transpiration of water, as well as
how and when the pesticide is applied. It has two major components:
hydrology and chemical transport.

The hydrologic component for calculating runoff and erosion of soil is
based on the USDA Natural Resource Conservation Service curve number
technique and the Universal Soil Loss Equation.  Evapotranspiration of
water from the root zone of the soil profile is estimated either
directly from pan evaporation data or is based on an empirical formula
(Penman 1948). Total evapotranspiration of water includes evaporation
from crop interception, evaporation from soil, and transpiration by the
crop. Water movement is simulated by the use of generalized soil
parameters, including field capacity, wilting point, and saturation
water content.  To reflect the high-end of the distribution of pesticide
exposures across varying sites, OPP selects hydrologic scenarios  based
on the targeting of model outputs.

The chemical transport component of PRZM-3 simulates pesticide
application on the soil or on the plant foliage. Dissolved, adsorbed,
and vapor-phase concentrations in the soil are estimated by
simultaneously considering the processes of pesticide uptake by plants,
surface runoff, erosion, decay, volatilization, foliar wash-off, and
sorption.

Each PRZM modeling scenario represents a unique combination of climatic
conditions, crop-specific management practices, soil-specific
properties, site-specific hydrology, and pesticide-specific application
and dissipation processes. Each PRZM simulation is conducted using up to
36 years of rainfall data to cover year-to-year variability in runoff.
PRZM-3 allows the user to consider pulse loads and predict peak events.
Daily edge-of-field loadings of pesticides dissolved in runoff waters
and sorbed to sediment, as predicted by PRZM, are discharged into a
standard water body ("standard pond" for ecological assessments)
simulated by the EXAMS model.

EXAMS II is also a process model that simulates the processes that
occur in the water body rather than on the agricultural field. EXAMS II
takes the runoff and spray drift loadings generated by PRZM and
estimates the concentration in the pond on a day-to-day basis.  It
accounts for volatilization, sorption, hydrolysis, biodegradation, and
photolysis of the pesticide in the aquatic environment.  Since EXAMS is
a steady-state model, the water bodies are modeled as having constant
volume.  Multiple-year pesticide concentrations in the water column are
calculated from the simulations as the annual daily peak, maximum annual
96-hour average, maximum annual 21-day average, maximum annual 60-day
average, and annual average. The 1 in 10 year maximum values for each
averaging period are used to calculate risk quotients. An input
parameters selection manual, which provides guidance in selecting input
values for using these models, can be found in Support Document #9.

For surface water modeling, PRZM/EXAMS assumes 5% and 1% spray drift for
aerially and ground applied pesticides, respectively.  The 5% assumption
is based on a linear interpolation of spray drift data presented in
Akesson (1990).  (See Section V.C.4.10 for a comparison of these assumed
drift levels with other drift modeling outputs.)  The risk
characterization section of the risk assessment includes a discussion of
the potential impact of alternative drift estimates on the overall
confidence of the risk assessment conclusions.

For pesticides that are currently on the market, water monitoring data
may be available   from EPA databases, U.S. Geological Survey, National
Water-Quality Assessment Program, industry, states, and universities.
These data are evaluated on a case-by-case basis to determine the
likelihood, extent, and nature of pesticide concentration in water under
current use practices and actual field conditions.  The risk assessment
team considers such study aspects as the points and frequency of sample
collection, the analyte suite, and detection limits when determining how
such data will be incorporated into the risk assessment. When reliable
surface water monitoring data are available, EPA uses it to help
characterize the levels of pesticide that are being detected in the
environment.  Monitoring, though, does not necessarily target pesticide
use areas or the time of year when pesticide concentrations may be at
their peak, and for this reason may not   provide a reliable estimate of
acute exposure.   If monitoring data shows higher confirmed detections
than estimated by modeling, the higher monitoring values may be used in
the risk assessment, and a re-evaluation of the model input parameters
may be initiated to explore the impact of selected input values on the
model output.

More detailed descriptions of these aquatic models can be found on
EPA’s Web site at the following url:
www.epa.gov/oppefed1/models/water/index.htm

(2).  Special Aquatic Exposure Methods for Pesticide Formulations tc \l5
"2).  Special Aquatic Exposure Methods for Pesticide Formulations

In situations where available toxicity data indicate that a pesticide
formulation for registration in the United States may be more toxic to
aquatic biota than indicated by active ingredient effects testing, it
may be necessary to consider aquatic exposure to the formulation.
Exposure modeling in these instances is limited to situations where
direct instantaneous introduction of the formulation to surface waters
occurs by direct application to those waters or by incidental
application as a result of drift.  The screening-level assessment model
for such direct or incidental application is based on the standard farm
pond scenario used for EXAMS modeling.

The limitation on the quantitative exposure modeling for formulations
is based on the expectation that the varying physical-chemical
properties of individual components of pesticide formulations will
result in progressively different formulation constituents in
environmental media over time.  As the proportions of formulation
components in environmental media differ from the proportions in the
tested formulation, the assumption that environmental residues are
toxicologically equivalent to tested formulations cannot be supported
beyond the time period immediately following product application.  This
assumption is especially important in the case of runoff from treated
areas to surface waters.  In this case, partitioning and degradation
properties for each formulation component suggest that the final
proportion of the residues of these components in the receiving surface
waters would not represent what was introduced and what was tested in an
aquatic organism toxicity study using the formulated product.

While EPA does not require the same data on end-use products as the EU,
the operation of the adverse effects reporting provisions in FIFRA
section 6(a)(2) and implementing regulations assure that EPA has the
same database for performing its ecological risk assessments as the EU.
The Agency’s methods for considering formulated product exposure in
the screening-level aquatic organism risk assessment is functionally
equivalent to the approaches developed by the European Union for
evaluating pesticide formulation risks (see Support Document #80 - EU
Council Directive 91/414/EEC).

c.  Terrestrial Organism Exposure Modeling tc \l4 "c.  Terrestrial
Organism Exposure Modeling

(1).  General Approach tc \l5 "(1).  General Approach

Terrestrial wildlife exposure estimates are typically calculated for
birds and mammals, emphasizing a dietary exposure route for uptake of
pesticide active ingredients.  These exposures are considered as
surrogates for terrestrial-phase amphibians as well as reptiles.  For
exposure to terrestrial organisms, OPP primarily looks at the residues
of pesticides on food items and assumes that organisms are exposed to a
single pesticide residue in a given exposure scenario.  Two approaches
are used for estimating exposure to terrestrial wildlife, which are
dependent on the application method: (1) spray applications and (2)
granular, bait, and treated seed applications.  Section V.B.1.c.2
describes the Agency’s approach for exposure modeling in situations
where available information suggests that formulation risks should be
considered.  It should be noted that, although the screening-level
terrestrial wildlife risk assessment focuses, in large part on dietary
exposure the Agency does consider the relative importance of other
routes of exposure in situations where data indicate that pesticide
exposures through routes other than dietary may be potentially
significant contributors to wildlife risk.  (Such data could be
identified, for example, through the ECOTOX database.  See Section
VI.B.2.b.1.)  OPP, in its risk characterization (see section VI.C),
discusses the impact of consideration of other routes of exposure that
have been identified as potentially important on the degree of certainty
associated with screening-level risk assessment conclusions.

For spray applications, estimation of pesticide concentrations in
wildlife food items   focuses on quantifying possible dietary ingestion
of residues on vegetative matter and insects.  The residue estimates are
based on a nomogram that relates food item residues to pesticide
application rate.  The nomogram is based on an EPA database called UTAB
(Uptake, Translocation, Accumulation, and Biotransformation), a
compilation of actual measured pesticide residue values on plants
(Nellessen and Fletcher 1992), and work from Fletcher et al. (1994).
(See Support Document #15).

In avian risk assessments, dietary residues are compared with toxicity
endpoints based on dietary concentration (e.g., LC50 for acute effects).
 Conversely residues may be first converted to an ingested whole body
dose. In the case of small mammals, for example, no dietary-based
toxicity information is available so residues are converted to an
ingested dose and compared to single oral-dose toxicity endpoints (i.e.,