![](media/image1.wmf){width="1.3576388888888888in"
height="1.375in"}UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

**March 31, 2008**

PC Code: 111401

DP Barcode: 348151

**[MEMORANDUM]{.underline}**

**Subject:** Registration Review: Preliminary Problem Formulation for
Ecological Risk, Environmental Fate, Endangered Species, and Drinking
Water Assessments for Profenofos

**To:** Christina Scheltema, Chemical Review Manager

> Kevin Costello, Team Leader
>
> Reregistration Branch
>
> Special Review and Reregistration Division
>
> Office of Pesticide Programs

**From:** Kristina Garber, Biologist

> Anita Pease, Senior Biologist

Environmental Risk Branch 4

Environmental Fate and Effects Division

Office of Pesticide Programs

**Through:** Elizabeth Behl, Chief

Environmental Risk Branch 4

Environmental Fate and Effects Division

Office of Pesticide Programs

The Environmental Fate and Effects Division (EFED) has completed the
preliminary problem formulation (attached) for the ecological risk,
environmental fate, endangered species, and drinking water assessments
to be conducted as part of the Registration Review of the
organophosphate insecticide/miticide, profenofos (PC Code 111401).
Functioning as the first stage of the risk assessment process for
registration review, this problem formulation provides an overview of
what is currently known about the environmental fate and ecological
effects associated with profenofos and its degradates. It also describes
the preliminary ecological risk hypothesis and analysis plan for
evaluating and characterizing risk to non-target species and the
environment in support of the registration of profenofos.

![](media/image2.wmf){width="1.8965277777777778in"
height="0.74375in"}Number range CHAPTER

![](media/image3.wmf){width="2.426388888888889in"
height="0.7152777777777778in"}

**Problem Formulation for the**

**Environmental Fate, Ecological Risk, Endangered Species, and Drinking
Water Assessments**

**in Support of the Registration Review of Profenofos**

![](media/image4.wmf){width="2.7715277777777776in"
height="1.4423611111111112in"}

Profenofos (CAS 41198-08-7)

+---------------------------------------+------------------------------+
| ***Prepared by:***                    | ***U. S. Environmental       |
|                                       | Protection Agency***         |
| Kristina Garber, Biologist            |                              |
|                                       | ***Office of Pesticide       |
| Anita Pease, Senior Biologist         | Programs***                  |
|                                       |                              |
|                                       | ***Environmental Fate and    |
|                                       | Effects Division***          |
|                                       |                              |
|                                       | ***Environmental Risk Branch |
|                                       | IV***                        |
|                                       |                              |
|                                       | ***1200 Pennsylvania Ave.,   |
|                                       | NW***                        |
|                                       |                              |
|                                       | ***Mail Code 7507P***        |
|                                       |                              |
|                                       | ***Washington, DC 20460***   |
+---------------------------------------+------------------------------+
| ***Reviewed by:***                    |                              |
|                                       |                              |
| Thomas Steeger, Senior Biologist      |                              |
|                                       |                              |
| R. David Jones, Senior Agronomist     |                              |
|                                       |                              |
| Elizabeth Behl, Branch Chief          |                              |
+---------------------------------------+------------------------------+

**March 31, 2008**

**Table of Contents**

[1. Purpose 4](#purpose)

[2. Problem Formulation 4](#problem-formulation)

[2.1. Nature of Regulatory Action 4](#nature-of-regulatory-action)

[2.2. Previous Risk Assessments 4](#previous-risk-assessments)

[3. Stressor Source and Distribution
6](#stressor-source-and-distribution)

[3.1. Mechanism of Action 6](#mechanism-of-action)

[3.2. Overview of Pesticide Usage 6](#overview-of-pesticide-usage)

[3.3. Environmental Fate and Transport
7](#environmental-fate-and-transport)

[3.3.1. Degradation 8](#degradation)

[3.3.2. Transport 9](#transport)

[3.3.3. Terrestrial Field Dissipation 9](#terrestrial-field-dissipation)

[3.3.4. Bioaccumulation 9](#bioaccumulation)

[4. Receptors 10](#receptors)

[4.1. Effects to Aquatic Organisms 10](#effects-to-aquatic-organisms)

[4.2. Effects to Terrestrial Organisms
11](#effects-to-terrestrial-organisms)

[4.3. Incident Database Review 13](#incident-database-review)

[4.4. Ecosystems Potentially at Risk
14](#ecosystems-potentially-at-risk)

[5. Assessment Endpoints 14](#assessment-endpoints)

[6. Conceptual Model 15](#conceptual-model)

[6.1. Risk Hypothesis 15](#risk-hypothesis)

[6.2. Conceptual Diagram 16](#conceptual-diagram)

[7. Analysis Plan 17](#analysis-plan)

[7.1. Stressors of Concern 18](#stressors-of-concern)

[7.2. Measures of Exposure 18](#measures-of-exposure)

[7.3. Measures of Effect 19](#measures-of-effect)

[7.4. Integration of Exposure and Effects
20](#integration-of-exposure-and-effects)

[7.5. Deterministic and Probabilistic Assessment Methods
21](#deterministic-and-probabilistic-assessment-methods)

[7.6. Endangered Species Assessments
21](#endangered-species-assessments)

[7.7. Drinking Water Assessment 22](#drinking-water-assessment)

[7.8. Preliminary Identification of Data Gaps
22](#preliminary-identification-of-data-gaps)

[7.8.1. Fate 22](#fate)

[7.8.2. Effects 23](#effects)

[8. References 27](#references)

[APPENDIX A: Preliminary EECs for aquatic habitats and RQs for aquatic
organisms.
32](#appendix-a-preliminary-eecs-for-aquatic-habitats-and-rqs-for-aquatic-organisms.)

[APPENDIX B: Preliminary EECs and associated RQs for terrestrial mammals
and birds
36](#appendix-b-preliminary-eecs-and-associated-rqs-for-terrestrial-mammals-and-birds)

[APPENDIX C: Preliminary EECs and associated RQs for terrestrial and
riparian plants
39](#appendix-c-preliminary-eecs-and-associated-rqs-for-terrestrial-and-riparian-plants)

#   {#section .unnumbered}

# 1. Purpose

The purpose of this problem formulation is to provide an understanding
of what is known about the environmental fate and ecological effects of
the registered uses of profenofos. Profenofos is an organophosphate used
as an insecticide and miticide on cotton. This document will provide a
plan for analyzing data relevant to profenofos and for conducting
environmental fate, ecological risk, endangered species and drinking
water assessments for its registered uses. Additionally, this problem
formulation is intended to identify data gaps, uncertainties, and
potential assumptions used to address those uncertainties relative to
characterizing the ecological risk associated with the registered uses
of profenofos.

# 2. Problem Formulation

## 2.1. Nature of Regulatory Action

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA),
all pesticides distributed or sold in the United States generally must
be registered by EPA. In determining whether a pesticide can be
registered in the U.S., EPA evaluates its safety to non-target species
based on a wide range of environmental and health effects studies. In
1996, FIFRA was amended by the Food Quality Protection Act, and EPA was
mandated to implement a new program for the periodic review of
pesticides, *i.e*., registration review
(<http://www.epa.gov/oppsrrd1/registration_review/>). The registration
review program is intended to ensure that, as the ability to assess risk
evolves and as policies and practices change, all registered pesticides
continue to meet the statutory standard of no unreasonable adverse
effects to human health and the environment. Changes in science, public
policy, and pesticide use practices will occur over time. Through the
new registration review program, the Agency periodically reevaluates
pesticides to make sure that as change occurs, products in the
marketplace can be used safely.

As part of the implementation of the new Registration Review program
pursuant to Section 3(g) of the Federal Insecticide, Fungicide and
Rodenticide Act (FIFRA), the Agency is beginning its evaluation of
profenofos to determine whether it continues to meet the FIFRA standard
for registration. This problem formulation for the environmental fate,
ecological risk, endangered species, and drinking water assessment
chapter in support of the registration review will be posted in the
initial docket opening the public phase of the review process.

## 2.2. Previous Risk Assessments

A national-level ecological risk assessment was completed as part of the
interim reregistration eligibility decision (IRED) for profenofos in
August 2000 (USEPA 2000). The IRED was finalized in July 2006 after the
cumulative human health risk assessment of the organophosphate (OP)
class of pesticides was completed (USEPA 2006). The ecological risk
assessment included in the profenofos IRED was based on laboratory fate
and ecotoxicological data submitted by the registrant in support of
reregistration and from data in publicly available literature, and
incident reports of adverse effects on non-target organisms associated
with the use of profenofos. The primary environmental concerns
identified in the 2000 environmental fate and ecological risk assessment
were associated with risks to freshwater and estuarine/marine fish and
invertebrates (USEPA 2000). Estimated risks to aquatic invertebrates,
which are not typically captured in incident reports, were higher than
those expected for fish, based on modeled exposure concentrations. The
Agency's levels of concern (LOCs) were exceeded for these aquatic
animals. Fish kill incidents received under FIFRA 6(a)(2) and summarized
in the Agency's Ecological Incident Information System (EIIS) provide
further evidence that profenofos poses a hazard to fish when used under
typical use conditions on cotton. For non-target terrestrial organisms,
the risk from profenofos exceeded acute and chronic levels of concern
for birds; acute levels of concern for small mammals; and triggered risk
concerns for endangered species. In addition, profenofos was reported as
highly toxic to honeybees.

Based on the results of the IRED, a number of mitigation measures were
implemented to address ecological risks for profenofos. The profenofos
label was modified to: (1) reduce the seasonal maximum application rate
from 6 to 5 lb a.i./A/season; (2) limit the 1 lb a.i./A rate to only
lepidopteran pests up to twice per season; (3) reduce the maximum
application rate under all other conditions to 0.75 lb a.i./A; (4)
require 300-ft spray drift and 100-ft run-off buffer zones around water
bodies for aerial and ground applications, respectively; (5) prohibit
use in Reeves County, Texas, and within one mile of the Dexter National
Fish Hatchery in New Mexico; and (6) prohibit application or drift of
profenofos to crops or weeds on which bees are foraging.

An emergency exemption petition (Section 18) risk assessment for use of
profenofos on rice (in Texas) was also completed in 2007 (USEPA 2007a).
The results of the Section 18 assessment indicated that the proposed use
of profenofos on rice for seed in Texas may result in acute and chronic
risk for terrestrial and aquatic animals. Potential risks to terrestrial
invertebrates and terrestrial and aquatic plants were identified as
well.

> **\
> *Final Biological Opinion on Profenofos in Response to Request for
> Consultation***

EPA reinitiated a formal consultation with the U. S. Fish and Wildlife
Service (USFWS) in 1989 regarding profenofos impacts on endangered
species. This consultation was on selected portions of five previous
"cluster" biological opinions evaluating pesticides for certain crops
(corn, cotton, soybeans, sorghum, wheat, barley, oats and rye), forestry
use pesticides, mosquito larvicides, and rangeland and pastureland
pesticides. As a result, the USFWS issued a formal Biological Opinion
(USFWS 1989), which identified reasonable and prudent measures and
alternatives to mitigate potential effects on Federally-listed
threatened/endangered species from the use of profenofos. The opinion
identified 6 amphibians, 77 fish, 38 freshwater mussels, and 10
arthropods potentially affected by the use of profenofos. Of the 131
species identified, 21 (16%) were classified as "in jeopardy".

# 3. Stressor Source and Distribution

## 3.1. Mechanism of Action

Profenofos, O-(4-bromo-2-chlorophenyl) O-ethyl S-propyl
phosphorothioate, is an insecticide/miticide belonging to the
organophosphate class of pesticides. Organophosphate toxicity is based
on the inhibition of the enzyme acetylcholinesterase, which cleaves the
neurotransmitter acetylcholine. Inhibition of acetylcholinesterase by
organophosphate insecticides interferes with proper neurotransmission in
cholinergic neurosynapses and neuromuscular junctions.

## 3.2. Overview of Pesticide Usage

Profenofos was originally registered for use in the United States in
1982. It is used to control cotton pests including aphids, lygus bugs
(*Lygus spp.*), and cotton bollworm (*Helicoverpa zea*). Currently,
labeled use of profenofos includes only applications to cotton. There is
one active Section 3 product containing profenofos (registration \#
100-669). According to this product label, profenofos can be applied to
cotton by aerial or ground methods. For general use, the maximum single
application rate is 0.75 lb a.i./A. Additional applications can be made
up to 5 lbs a.i/A/season (this is equivalent to 6 applications of 0.75
lb a.i./A plus 1 application of 0.5 lb a.i./A). For lepidopteran pests,
the maximum single application rate per season is 1 lb a.i./A with 2
applications per season for a total of 2 lbs a.i./A/ season.

[]{.mark}

As of 2002, an estimated 153,000 pounds of profenofos were applied
annually in the United States (**Figure 1**). According to National
Agricultural Statistics Services data from 2000-2007, cotton was planted
in Alabama, Arizona, Arkansas, California, Florida, Georgia, Kansas,
Louisiana, Mississippi, Missouri, New Mexico, North Carolina, Oklahoma,
South Carolina, Tennessee, Texas and Virginia (USDA 2007). Therefore,
potential application sites of profenofos are expected to include these
states.

![](media/image5.png){width="6.731944444444444in"
height="5.207638888888889in"}

Figure 1. Historical Extent (2002) of profenofos usage.

(Source
http://ca.water.usgs.gov/pnsp/pesticide_use_maps/show_map.php?year=02&map=m6084
).

[]{.mark}

## 3.3. Environmental Fate and Transport

[]{.mark}

Registrant-submitted data defining the physical, chemical, fate and
transport characteristics associated with profenofos are summarized in
**Table 1**. As part of registration review, available fate studies for
profenofos have been reevaluated. The fate and transport of profenofos
in the environment is briefly discussed below.

+--------------------------------+-------------------+-----------------+
| **Table 1. General chemical    |                   |                 |
| and environmental fate         |                   |                 |
| properties of profenofos.**    |                   |                 |
+================================+===================+=================+
| **Chemical/Fate parameter**    | **Value**         | **Source        |
|                                |                   | (MRID)**        |
+--------------------------------+-------------------+-----------------+
| Molecular Weight (g/mol)       | 373.63            | Product         |
|                                |                   | chemistry       |
+--------------------------------+-------------------+-----------------+
| Vapor Pressure (torr)          | 3.46 E^-06^       | 41905001        |
+--------------------------------+-------------------+-----------------+
| Octanol-water Partition        | 4.83 (25 °C)      | EFGWB Science   |
| Coefficient (Log K~OW~)        |                   | Chapter (USEPA  |
|                                |                   | 1996)           |
+--------------------------------+-------------------+-----------------+
| Octanol-air Partition          | 10.7              | EPIsuite,       |
| Coefficient (Log K~OA~)        |                   | v.3.20          |
+--------------------------------+-------------------+-----------------+
| Water Solubility (mg/L; at 25  | 20                | IRED (USEPA     |
| °C)                            |                   | 2000)           |
+--------------------------------+-------------------+-----------------+
| Henry\'s Law Constant          | 2.38 x 10^‑7^     | EFGWB Science   |
| (atm-m^3^ mol^‑1^)             |                   | Chapter (USEPA  |
|                                |                   | 1996)           |
+--------------------------------+-------------------+-----------------+
| Hydrolysis half lives (days)   | 104 - 108 (pH 5)  | 416276309,      |
|                                |                   |                 |
|                                | 24 - 62 (pH 7)    | 41939001        |
|                                |                   |                 |
|                                | 0.3 (pH 9)        |                 |
+--------------------------------+-------------------+-----------------+
| Aqueous photolysis half-life   | stable            | 41879901,       |
|                                |                   | 41939002        |
+--------------------------------+-------------------+-----------------+
| Soil Photolysis half-life      | 9.5               | 44683901        |
| (days)^1^                      |                   |                 |
+--------------------------------+-------------------+-----------------+
| Aerobic Soil Metabolism        | 3                 | 42334302        |
| half-life (days)               |                   |                 |
+--------------------------------+-------------------+-----------------+
| Anaerobic Soil Metabolism      | 12.4              | 42334303        |
| half-life (days)               |                   |                 |
+--------------------------------+-------------------+-----------------+
| Anaerobic Aquatic Metabolism   | 4                 | 42218101        |
| half-life (days)               |                   |                 |
+--------------------------------+-------------------+-----------------+
| Organic carbon normalized      | 185 ^2^           | EPIsuite,       |
| partition coefficients (K~OC~) |                   | v.3.20          |
+--------------------------------+-------------------+-----------------+
| Fish Bioconcentration Factor   | 29x (body)        | 00085952,       |
| (BCF)                          |                   |                 |
|                                | 45x (head)        | 92148059        |
|                                |                   |                 |
|                                | 682x (viscera)    |                 |
+--------------------------------+-------------------+-----------------+

^1^Represents environmental soil photolysis half-life (12 h light, 12 h
dark).

^2^Estimated value.

### 3.3.1. Degradation

Available laboratory studies indicate that profenofos degrades by
microbial metabolism as well as the abiotic process of hydrolysis.
Aerobic and anaerobic soil metabolism half-lives are similar, ranging 3
to 12.4 days. Degradation due to hydrolysis varies with pH, with
half-life values of 104-108 days for acidic (pH 5) waters, 24-62 days
for neutral waters (pH 7) and 0.3 days for alkaline waters (pH 9). Under
anaerobic aquatic conditions, the half-life of profenofos due to
metabolism is 4 days. In water, under sterile conditions, profenofos is
stable to photolysis; however, in soil, under non-sterile conditions,
profenofos has a photolysis half-life of 9.5 days.

[]{.mark}

The predominant degradate of profenofos observed in laboratory studies
(including hydrolysis, photolysis and metabolism) was
4-bromo-2-chlorophenol, which was formed by hydrolysis of the
organophosphate group from the phenyl ring of profenofos. Also formed in
equimolar parts with this degradate is O-ethyl-S-propyl phosphorthioate.

### 3.3.2. Transport 

No scientifically valid studies are available to define the mobility of
profenofos or its degradates in soil. The estimated organic carbon
partition coefficient (K~oc~) of 185 (EPIsuite, v.3.20) suggests that
profenofos may be moderately mobile in soil.

Laboratory studies show that some profenofos residues may be released to
the atmosphere through volatilization. Over 30 days, volatility of
profenofos residues averaged 6.13 x 10^‑3^ µg/cm^2^/hr and the vapor
pressure averaged 3.46 x 10^‑6^ torr (MRID: 419050-01). In this study,
4‑bromo‑2‑chlorophenol was the major volatile residue.

[]{.mark}

### 3.3.3. Terrestrial Field Dissipation

The submitted field studies do not provide adequate information for more
than a rough qualitative assessment of profenofos dissipation in the
field, in large part because profenofos degraded during storage. Both
profenofos and its degradate, 4‑bromo‑2‑chlorophenol, dissipated from
the surface to 6 inches in cotton and bare-ground plots in California
and Texas with a half-life of several days (MRIDs: 428513-01,
429009-01). Neither profenofos, nor 4-bromo-2-chlorophenol was detected
below 12 inches in either study (minimum detection limit of 10 ppb).
Because the studies were conducted in soil and weather conditions that
resulted in a moisture deficit there was little or no excess water
available for downward movement through the soil.

###  3.3.4. Bioaccumulation

In a bioconcentration study with bluegill sunfish, profenofos residues
concentrated in fish tissues at a factor of 29X for whole fish. The
dominant chemical identified in the viscera is 4‑bromo‑2‑chlorophenol
(33‑48% of the recovered radioactivity). Once fish were moved to water
not containing profenofos, depuration was rapid, with 96% of profenofos
residues eliminated from fish tissues within 8 days (MRIDs 00085952 and
summarized in 92148059).

The octanol-water partition coefficient (Log K~OW~ = 4.83) indicates
that profenofos has the potential to bioaccumulate in aquatic
ecosystems; however, bioaccumulation may be limited by metabolism of
profenofos to 4-bromo-2-chlorophenol and other degradates.

The estimated log octanol-air partition coefficient (Log K~OA~) of 10.7
(EPIsuite, v.3.20) suggests that bioaccumulation of profenofos in
terrestrial food chains is possible (Kelly *et al*. 2007).

Potential bioaccumulation of profenofos will be considered in future
risk assessments.

# 4. Receptors

Consistent with the process described in the Overview Document (USEPA
2004), the risk assessment for profenofos relies on a surrogate species
approach. T**Number range CHAPTER**oxicological data generated from
surrogate test species, which are intended to be representative of broad
taxonomic groups, are used to extrapolate to potential effects on a
variety of species (receptors) included under these taxonomic groupings.
Based on previous assessments (*e.g*., see the IRED, USEPA 2000), no
major degradates of toxicological concern were identified; therefore,
the focus of the assessment is parent profenofos.

Acute and chronic toxicity data from studies submitted by pesticide
registrants along with the available open literature are used to
evaluate the potential direct and indirect effects of profenofos to
aquatic and terrestrial receptors. This includes toxicity on the
technical grade active ingredient, degradates, and when available,
formulated products (*e.g.*, "Six-Pack" studies). The open literature
studies are identified through EPA's ECOTOXicology (ECOTOX) database
(USEPA 2007*d*), which employs a literature search engine for locating
chemical toxicity data for aquatic life, terrestrial plants, and
wildlife. The evaluation of both sources of data may also provide
insight into the direct and indirect effects of profenofos on biotic
communities from loss of species that are sensitive to the chemical and
from changes in structure and functional characteristics of the affected
communities. Open literature data from ECOTOX on profenofos will be
available in September 2008, and subsequently evaluated for possible
quantitative and/or qualitative inclusion in this risk assessment.

A summary of the aquatic and terrestrial toxicity data used to derive a
preliminary evaluation of risk for profenofos is provided in Sections
4.1 and 4.2, respectively. In addition, a summary of ecological
incidents associated with profenofos and a description of ecosystems
potentially at risk are provided in Sections 4.3 and 4.4, respectively.

## 4.1. Effects to Aquatic Organisms

A summary of the most sensitive aquatic toxicity data from
registrant-submitted studies is provided in **Table 2**. Profenofos is
classified as very highly toxic to freshwater and estuarine/marine fish
and invertebrates on an acute exposure basis. Chronic effects in
freshwater fish and invertebrates and estuarine/marine invertebrates
include diminished survival and growth. No chronic data are available
for estuarine/marine fish. Toxicity data for aquatic plants are also not
available for profenofos.

+------------+---------+-----+------+---------+---------+----------+
| **Table 2. |         |     |      |         |         |          |
| Summary of |         |     |      |         |         |          |
| most       |         |     |      |         |         |          |
| sensitive  |         |     |      |         |         |          |
| endpoints  |         |     |      |         |         |          |
| from       |         |     |      |         |         |          |
| submitted  |         |     |      |         |         |          |
| aquatic    |         |     |      |         |         |          |
| toxicity   |         |     |      |         |         |          |
| studies    |         |     |      |         |         |          |
| for        |         |     |      |         |         |          |
| pro        |         |     |      |         |         |          |
| fenofos.** |         |     |      |         |         |          |
+============+=========+=====+======+=========+=========+==========+
| *          | **Taxa  | *   | **Du | **Mean  | **Cit   | **Acute  |
| *Species** | Repres  | *En | rati | concen  | ation** | Toxicity |
|            | ented** | d-p | on** | tration |         | Classifi |
| **(common  |         | oin |      | (µg     | *       | cation** |
| name)**    |         | t** | **(  | a.      | *MRID** |          |
|            |         |     | hour | i./L)** |         |          |
|            |         |     | s)** |         |         |          |
+------------+---------+-----+------+---------+---------+----------+
| *Lepomis   | Fre     | LC~ | 96   | 14.1\*  | 400     | Very     |
| ma         | shwater | 50~ |      |         | 9801-01 | highly   |
| crochirus* | fish    |     |      |         |         | toxic    |
|            | and     |     |      |         | (Mayer  |          |
| (Bluegill  | aquati  |     |      |         | and     |          |
| Sunfish)   | c-phase |     |      |         | Ell     |          |
|            | amp     |     |      |         | ersieck |          |
|            | hibians |     |      |         | 1986)   |          |
+------------+---------+-----+------+---------+---------+----------+
| *          |         | NO  | 31   | 2.0     | 00      | NA       |
| Pimephales |         | AEC | (d   |         | 0859-58 |          |
| promelas*  |         |     | ays) |         |         |          |
|            |         |     |      |         | (       |          |
| (Fathead   |         |     |      |         | LeBlanc |          |
| Minnow)    |         |     |      |         | et al.  |          |
|            |         |     |      |         | 1979)   |          |
+------------+---------+-----+------+---------+---------+----------+
|            |         | LO  |      | 4.4     |         |          |
|            |         | AEC |      |         |         |          |
+------------+---------+-----+------+---------+---------+----------+
| *Daphnia   | Fre     | EC~ | 48   | 0.93\*  | 41      | Very     |
| magna*     | shwater | 50~ |      |         | 6273-04 | highly   |
|            | Invert  |     |      |         |         | toxic    |
| (Water     | ebrates |     |      |         | (Bel    |          |
| Flea)      |         |     |      |         | lantoni |          |
|            |         |     |      |         | 1990)   |          |
+------------+---------+-----+------+---------+---------+----------+
|            |         | NO  | 42   | 0.2     | 00      | NA       |
|            |         | AEC | (d   |         | 0859-64 |          |
|            |         |     | ays) |         |         |          |
|            |         |     |      |         | (       |          |
|            |         |     |      |         | LeBlanc |          |
|            |         |     |      |         | and     |          |
|            |         |     |      |         | Sur     |          |
|            |         |     |      |         | prenant |          |
|            |         |     |      |         | 1980)   |          |
+------------+---------+-----+------+---------+---------+----------+
|            |         | LO  |      | 0.33    |         |          |
|            |         | AEC |      |         |         |          |
+------------+---------+-----+------+---------+---------+----------+
| *Lagodon   | Est     | LC~ | 96   | 7.7\*   | 00      | Very     |
| rhomboids* | uarine/ | 50~ |      |         | 0859-60 | highly   |
| (Pinfish)  | Marine  |     |      |         |         | toxic    |
|            | Fish    |     |      |         | (Hei    |          |
|            |         |     |      |         | tmuller |          |
|            |         |     |      |         | 1980)   |          |
+------------+---------+-----+------+---------+---------+----------+
| *          | Est     | LC~ | 96   | 2.4     | 00      | Very     |
| Mysidopsis | uarine/ | 50~ |      |         | 0859-63 | highly   |
| bahia*     | Marine  |     |      |         |         | toxic    |
|            | Invert  |     |      |         | (Ho     |          |
| (Mysid     | ebrates |     |      |         | llister |          |
| shrimp)    |         |     |      |         | 1980)   |          |
+------------+---------+-----+------+---------+---------+----------+
|            |         | NO  | 28   | 0.22    | 00      | NA       |
|            |         | AEC | (d   |         | 0859-63 |          |
|            |         |     | ays) |         |         |          |
|            |         |     |      |         | (Ho     |          |
|            |         |     |      |         | llister |          |
|            |         |     |      |         | 1980)   |          |
+------------+---------+-----+------+---------+---------+----------+
|            |         | LO  |      | 0.35    |         |          |
|            |         | AEC |      |         |         |          |
+------------+---------+-----+------+---------+---------+----------+
| \* Based   |         |     |      |         |         |          |
| on nominal |         |     |      |         |         |          |
| conce      |         |     |      |         |         |          |
| ntrations. |         |     |      |         |         |          |
+------------+---------+-----+------+---------+---------+----------+

[]{.mark}

## 4.2. Effects to Terrestrial Organisms

Available data on the toxicity of profenofos to terrestrial plants and
animals are summarized in **Tables 3 and 4**, respectively.

Tier II seedling emergence and vegetative vigor data are available to
assess the toxicity of profenofos to terrestrial plants. In the Tier II
seedling emergence test, the dicotyledonous (dicot) cucumber (*Cucumis
sativus*) was the most sensitive species, based on plant dry weight.
Effect concentrations for 25% of the plants (EC~25~) could not be
established for any of the other dicots tested, although lettuce
(*Lactuca sativa*) and cabbage (*Brassica oleracea*) dry weight were
also affected at concentrations below the maximum application rate. No
adverse effects were observed in monocotyledonous plants (monocots) at
the highest test concentration in the Tier II seedling emergence test.
In Tier II vegetative vigor studies, there were no adverse effects for
any of the tested monocots or dicots at the highest treatment level (1.0
lb a.i./A).

+----------+-------+------+-------------+-------+---------+---------+
| **Table  |       |      |             |       |         |         |
| 3.       |       |      |             |       |         |         |
| Summary  |       |      |             |       |         |         |
| of       |       |      |             |       |         |         |
| s        |       |      |             |       |         |         |
| ubmitted |       |      |             |       |         |         |
| toxicity |       |      |             |       |         |         |
| studies  |       |      |             |       |         |         |
| for      |       |      |             |       |         |         |
| ter      |       |      |             |       |         |         |
| restrial |       |      |             |       |         |         |
| o        |       |      |             |       |         |         |
| rganisms |       |      |             |       |         |         |
| exposed  |       |      |             |       |         |         |
| to       |       |      |             |       |         |         |
| profe    |       |      |             |       |         |         |
| nofos.** |       |      |             |       |         |         |
+==========+=======+======+=============+=======+=========+=========+
| **S      | **Me  | *    | **Mean      | *     | **Study | **C     |
| pecies** | asure | *End | Conc        | *Test | Cl      | itation |
|          | of    | -poi | entration** | Subs  | assific | MRID**  |
| *        | eff   | nt** |             | tance | ation** |         |
| *(common | ect** |      | **(lbs      | (%    |         |         |
| name)**  |       |      | a.i./A)**   | a.    |         |         |
|          |       |      |             | i.)** |         |         |
+----------+-------+------+-------------+-------+---------+---------+
| Cucumber | See   | EC   | 0.13        | 90.4  | Acc     | 41      |
| (dicot)  | dling | ~25~ |             |       | eptable | 6273-07 |
|          | Emer  |      |             |       |         |         |
|          | gence |      |             |       |         | (       |
|          |       |      |             |       |         | Chetram |
|          | (Tier |      |             |       |         | 1990)   |
|          | 2)    |      |             |       |         |         |
|          |       |      |             |       |         |         |
|          | (dry  |      |             |       |         |         |
|          | we    |      |             |       |         |         |
|          | ight) |      |             |       |         |         |
+----------+-------+------+-------------+-------+---------+---------+
|          |       | N    | 0.11        |       |         |         |
|          |       | OAEC |             |       |         |         |
+----------+-------+------+-------------+-------+---------+---------+
| All      | See   | N    | \>1.0       | 90.4  | Acc     | 41      |
| tested   | dling | OAEC |             |       | eptable | 6273-07 |
| monocots | Emer  |      |             |       |         |         |
|          | gence |      |             |       |         | (       |
|          |       |      |             |       |         | Chetram |
|          | (Tier |      |             |       |         | 1990)   |
|          | 2)    |      |             |       |         |         |
+----------+-------+------+-------------+-------+---------+---------+
| All      | Veget | N    | \>1.0       | 90.4  | Acc     | 41      |
| tested   | ative | OAEC |             |       | eptable | 6273-05 |
| monocots | Vigor |      |             |       |         |         |
| and      |       |      |             |       |         | (       |
| dicots   | (Tier |      |             |       |         | Chetram |
|          | 2)    |      |             |       |         | 1990)   |
+----------+-------+------+-------------+-------+---------+---------+

Profenofos is classified as moderately toxic to mammals and birds on an
acute oral basis, and highly toxic to birds on a sub-acute dietary
exposure basis. Body weight was reduced in parents and offspring in the
rat (*Ratus norvegicus*) 2-generation reproduction study. Avian
reproduction studies indicate that profenofos causes reproductive
impairment (*i.e*., reduction in egg production) to Northern bobwhite
quail (*Colinus virginianus*). Profenofos is highly toxic to honey bees
(*Apis mellifera*) on an acute contact exposure basis.

[]{.mark}

+---------+----------+-----+-------------+------+---------+---------+
| **Table |          |     |             |      |         |         |
| 4.      |          |     |             |      |         |         |
| Summary |          |     |             |      |         |         |
| of most |          |     |             |      |         |         |
| se      |          |     |             |      |         |         |
| nsitive |          |     |             |      |         |         |
| en      |          |     |             |      |         |         |
| dpoints |          |     |             |      |         |         |
| from    |          |     |             |      |         |         |
| su      |          |     |             |      |         |         |
| bmitted |          |     |             |      |         |         |
| terr    |          |     |             |      |         |         |
| estrial |          |     |             |      |         |         |
| t       |          |     |             |      |         |         |
| oxicity |          |     |             |      |         |         |
| studies |          |     |             |      |         |         |
| for     |          |     |             |      |         |         |
| profen  |          |     |             |      |         |         |
| ofos.** |          |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| **Sp    | **Taxa   | *   | **Mean      | **   | **Cit   | **Acute |
| ecies** | Repre    | *En | Conc        | Test | ation** | T       |
|         | sented** | d-p | entration** | S    |         | oxicity |
| **      |          | oin |             | ubst | *       | Cl      |
| (common |          | t** |             | ance | *MRID** | assific |
| name)** |          |     |             | (%   |         | ation** |
|         |          |     |             | a.i  |         |         |
|         |          |     |             | .)** |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| Mouse   | Mammals  | LD~ | 298         | T    | 00      | Mod     |
|         |          | 50~ | mg/kg-bw    | ech. | 1052-26 | erately |
|         |          |     |             |      |         | toxic   |
+---------+----------+-----+-------------+------+---------+---------+
| *Rattus |          | NO  | 7.3         | 89   | 43      | NA      |
| norv    |          | AEL | mg/kg-bw    |      | 2133-08 |         |
| egicus* |          |     |             |      |         |         |
|         |          |     |             |      | 43      |         |
| (Lab    |          |     |             |      | 2133-09 |         |
| oratory |          |     |             |      |         |         |
| Rat)    |          |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
|         |          | LO  | 29          |      |         |         |
|         |          | AEL | mg/kg-bw\*  |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| *Anas   | Birds,   | LD~ | 55 mg/kg-bw | 89.4 | 41      | Mod     |
| platyrh | terr     | 50~ |             |      | 6273-01 | erately |
| ynchos* | estrial- |     |             |      |         | toxic   |
|         | phase    |     |             |      | (P      |         |
| (       | amp      |     |             |      | edersen |         |
| Mallard | hibians, |     |             |      | 1990)   |         |
| Duck)   | and      |     |             |      |         |         |
|         | reptiles |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| *       |          | LC~ | 57          | T    | 43      | Highly  |
| Colinus |          | 50~ | mg/kg-diet  | ech. | 1073-01 | toxic   |
| virgi   |          |     |             |      |         |         |
| nianus* |          |     |             |      | (Brewer |         |
|         |          |     |             |      | and     |         |
| (N      |          |     |             |      | Tal     |         |
| orthern |          |     |             |      | iaferro |         |
| B       |          |     |             |      | 1994)   |         |
| obwhite |          |     |             |      |         |         |
| Quail)  |          |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
|         |          | NO  | \<1         | 90.6 | 00      | NA      |
|         |          | AEC | mg/kg-diet  |      | 0866-61 |         |
|         |          |     |             |      |         |         |
|         |          |     |             |      | (Fink   |         |
|         |          |     |             |      | and     |         |
|         |          |     |             |      | Beavers |         |
|         |          |     |             |      | 1978)   |         |
+---------+----------+-----+-------------+------+---------+---------+
|         |          | LO  | 1           |      |         |         |
|         |          | AEC | mg/         |      |         |         |
|         |          |     | kg-diet\*\* |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| *Apis   | Ter      | LD~ | 0.0953      | 90.4 | 41      | Highly  |
| mel     | restrial | 50~ | µg/bee      |      | 6273-08 | toxic   |
| lifera* | inver    |     |             |      |         |         |
|         | tebrates |     |             |      | (Winter |         |
| (Honey  |          |     |             |      | 1990)   |         |
| Bee)    |          |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+
| \*Based |          |     |             |      |         |         |
| on      |          |     |             |      |         |         |
| re      |          |     |             |      |         |         |
| duction |          |     |             |      |         |         |
| in body |          |     |             |      |         |         |
| weight. |          |     |             |      |         |         |
|         |          |     |             |      |         |         |
| \*      |          |     |             |      |         |         |
| \*Based |          |     |             |      |         |         |
| on      |          |     |             |      |         |         |
| repro   |          |     |             |      |         |         |
| ductive |          |     |             |      |         |         |
| impa    |          |     |             |      |         |         |
| irment. |          |     |             |      |         |         |
+---------+----------+-----+-------------+------+---------+---------+

[]{.mark}

## 4.3. Incident Database Review

A preliminary review of the Ecological Incident Information System
(EIIS) maintained by the Agency's Office of Pesticide Programs (OPP)
indicates a total of 26 reported ecological incidents associated with
the use of profenofos. All reported incidents involved mortalities to
aquatic animals and occurred between 1989 and 1999 in Alabama, Georgia,
Louisiana, and Mississippi. Although past and current registrations for
profenofos have been limited to use on cotton, 17 of the 26 incidents
were reported for cotton uses, while two of the areas were defined as
agricultural areas, and the remaining five areas were undefined. Two of
the profenofos uses associated with the incidents were accidental
misuses of the chemical, 12 incidents were associated with registered
uses, and the remaining 12 incidents were undetermined. The certainty
that the incidents were associated with profenofos exposure was
considered unlikely (3 incidents), possible (7 incidents), probable (10
incidents) and highly probable (6 incidents). No incidents associated
with adverse field effects of profenofos to non-target terrestrial
animals or plants have been reported in the EIIS.

Although the number of reported incidents has dropped considerably since
mitigation measures were implemented following the 2000 IRED, the
absence of reported incidents from 2000 to the present should not be
construed as the absence of incidents. Incident reports for non-target
plants and animals typically provide information on mortality events
only. Reports for other adverse effects, such as reduced growth or
impaired reproduction, are rarely received. EPA's changes in the
registrant reporting requirements of incidents may also account for the
reduced number of reported incidents. Registrants are now only required
to submit detailed information on 'major' incidents. Minor incidents are
generally reported aggregately and are not included in EIIS. In
addition, there have been changes in state monitoring efforts due to
lack of resources. However, the incident data that are available
indicate that exposure pathways are complete and that exposure levels
are sufficient to result in field-observable effects. It is also
important to note that the incident data indicate that the potential
risks to aquatic animals discussed in the ecological risk assessment in
support of the reregistration eligibility decision were supported by
actual incidents occurring in the field.

## 4.4. Ecosystems Potentially at Risk

The ecosystems at risk are often extensive in scope; therefore, it may
not be possible to identify specific ecosystems during the development
of a nation-wide ecological risk assessment. However, in general terms,
terrestrial ecosystems potentially at risk could include the treated
field and immediately adjacent areas that may receive drift or runoff.
Areas adjacent to the treated field could include cultivated fields,
fencerows and hedgerows, meadows, fallow fields or grasslands,
woodlands, riparian habitats and other uncultivated areas.

Aquatic ecosystems potentially at risk include water bodies adjacent to,
or down stream from, the treated field and could include impounded
bodies such as ponds, lakes and reservoirs, or flowing waterways such as
streams or rivers. For uses in coastal areas, aquatic habitat also
includes marine ecosystems, including estuaries.

# 5. Assessment Endpoints

Assessment endpoints represent the actual environmental value that is to
be protected, defined by an ecological entity (species, community, or
other entity) and its attribute or characteristics (USEPA 1998). For
profenofos, the ecological entities may include the following: birds,
mammals, terrestrial-phase amphibians, reptiles, freshwater fish and
invertebrates, aquatic-phase amphibians, estuarine/marine fish and
invertebrates, terrestrial plants, insects, and aquatic plants and
algae. The attributes for each of these entities may include growth,
reproduction, and survival.

# 6. Conceptual Model

For a pesticide to pose an ecological risk, it must reach ecological
receptors in biologically significant concentrations. An exposure
pathway is the means by which a pesticide moves in the environment from
a source to an ecological receptor. For an ecological pathway to be
complete, it must have a source, a release mechanism, an environmental
transport medium, a point of exposure for ecological receptors, and a
feasible route of exposure.

The conceptual model for profenofos provides a written description and
visual representation of the predicted relationships between profenofos,
potential routes of exposure, and the predicted effects for the
assessment endpoint. A conceptual model consists of two major
components: risk hypothesis and a conceptual diagram (USEPA 1998).

Based on preliminary estimated environmental concentrations (EECs) and
effects data, preliminary risk quotients (RQs) were calculated for
aquatic animals (**Appendix A**) and terrestrial animals and plants
(**Appendices B and C**). Based on maximum application rates and
available fate data for profenofos, estimated acute and chronic RQ
values are sufficient to exceed levels of concern (LOCs) for
Federally-listed threatened/endangered (listed) and non-listed fish and
invertebrates. Risks are also expected for non-listed and listed birds
and mammals due to acute and chronic exposures to profenofos. Risks are
expected as well for non-listed and listed species of dicots inhabiting
semi-aquatic areas based on exposures of profenofos originating from the
maximum application rate. Because of the potential risk from direct
effects to the listed and non-listed taxa described above, listed
species in all taxa may potentially be affected indirectly due to
alterations in their habitat and prey items (*e.g*., food sources,
shelter, and areas to reproduce). These preliminary conclusions are used
to derive the risk hypothesis and conceptual diagram discussed below.

## 6.1. Risk Hypothesis

A risk hypothesis describes the predicted relationship among the
stressor, exposure, and assessment endpoint response along with the
rationale for their selection. For profenofos, the following ecological
risk hypothesis is being employed for this ecological risk assessment:

> *Based on the application methods, mode of action, fate and transport,
> and the sensitivity of non-target aquatic and terrestrial species,
> profenofos has the potential to reduce survival, reproduction, and/or
> growth in non-target terrestrial and aquatic organisms when used in
> accordance with the current label. These non-target organisms include
> Federally listed threatened and endangered species as well as
> non-listed species.*

##  6.2. Conceptual Diagram

[]{.mark}

The environmental fate properties of profenofos indicate that runoff,
spray drift, volatilization and direct spray represent potential
transport mechanisms of profenofos to aquatic and terrestrial habitats
where non-target organism may be exposed. These transport mechanisms
(*i.e*., sources) are depicted in the conceptual models below (**Figures
2 and 3**) along with the receptors of concern and the potential
attribute changes in the receptors due to exposures of profenofos.

[]{.mark}

**Figure 2. Conceptual model for profenofos effects on aquatic
organisms. Dotted lines indicate exposure pathways that have a low
likelihood of contributing to ecological risk.**

[]{.mark}

Figure 3. Conceptual model for profenofos effects on terrestrial
organisms.

# 7. Analysis Plan

In order to address the risk hypothesis, the potential for adverse
effects on the environment is estimated. The use, environmental fate,
and ecological effects of profenofos are characterized and integrated to
assess the risks. This is accomplished using a risk quotient (ratio of
exposure concentration to effects concentration) approach. Although risk
is often defined as the likelihood and magnitude of adverse ecological
effects, the risk quotient-based approach does not provide a
quantitative estimate of likelihood and/or magnitude of an adverse
effect. However, as outlined in the Overview Document (USEPA 2004), the
likelihood of effects to individual organisms from particular uses of
profenofos is estimated using the probit dose-response slope and either
the level of concern (discussed below) or the actual calculated risk
quotient value.

This analysis plan will be revisited and may be revised depending upon
the data available in the open literature and the information submitted
by the public in response to the opening of the Registration Review
docket.

##  7.1. Stressors of Concern

As discussed above, profenofos degrades into 4-bromo-2-chlorophenol and
O-ethyl-S-propyl phosphorthioate. Based on previous assessments (*e.g*.,
see the IRED, USEPA 2000), no major degradates of toxicological concern
were identified. Therefore, the focus of this assessment is expected to
be the parent, profenofos. However, the Agency will review all available
current degradate ecotoxicity data to identify any additional stressors
of concern for this assessment.

In its ecological risk assessments, the Agency does not routinely
include 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 (that is, a registered product containing more than
one active ingredient), 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 containing more than one active ingredient, the data
may be used qualitatively or quantitatively in accordance with the
Agency's Overview Document and the Services' Evaluation Memorandum
(USEPA 2004; USFWS/NMFS 2004).

Available toxicity data for environmental mixtures of profenofos with
other pesticides will be presented as part of the ecological risk
assessment. It is expected that the toxic effect of profenofos, in
combination with other pesticides used in the environment, is likely to
be a function of many factors including but not necessarily limited to:
(1) the exposed species, (2) the co-contaminants in the mixture, (3) the
ratio of profenofos and co-contaminant concentrations, (4) differences
in the pattern and duration of exposure among contaminants, and (5) the
differential effects of other physical/chemical characteristics of the
receiving waters (*e.g.* organic matter present in sediment and
suspended water). Quantitatively predicting the combined effects of all
these variables on mixture toxicity to any given taxa with confidence is
beyond the capabilities of the available data and methodologies.
However, a qualitative discussion of implications of the available
pesticide mixture effects data on the confidence of risk assessment
conclusions will be addressed as part of the uncertainty analysis.

##  7.2. Measures of Exposure

In order to estimate risks of profenofos exposures in aquatic and
terrestrial environments, all exposure modeling and resulting risk
conclusions will be made based on maximum application rates for cotton
discussed in Section 5. Measures of exposure are based on aquatic and
terrestrial models that predict estimated environmental concentrations
of profenofos using maximum labeled application rates and methods, as
well as any mitigation measures specifically indicated on the label
(*e.g.* spray drift buffers). The models used to predict aquatic EECs
are the Pesticide Root Zone Model coupled with the Exposure Analysis
Model System (PRZM/EXAMS). The model used to predict terrestrial EECs on
food items is T-REX. The model used to derive EECs relevant to
terrestrial and wetland plants is TerrPlant. These models are
parameterized using relevant reviewed registrant-submitted environmental
fate data.

[]{.mark}

PRZM (v3.12.2, May 2005) and EXAMS (v2.98.4.6, April 2005) are screening
simulation models coupled with the input shell pe5.pl (Aug 2007) to
generate daily exposures and 1-in-10 year EECs of profenofos that may
occur in surface water bodies adjacent to application sites receiving
profenofos through runoff and spray drift. PRZM simulates pesticide
application, movement and transformation on an agricultural field and
the resultant pesticide loadings to a receiving water body via runoff,
erosion and spray drift. EXAMS simulates the fate of the pesticide and
resulting concentrations in the water body. The standard scenario used
for ecological pesticide assessments assumes application to a 10-hectare
agricultural field that drains into an adjacent 1-hectare water body
that is 2 meters deep (20,000 m^3^ volume) with no outlet. PRZM/EXAMS is
used to estimate screening-level exposure of aquatic organisms to
profenofos. The measure of exposure for aquatic species is the 1-in-10
year return peak or rolling mean concentration. The 1-in-10 year peak is
used for estimating acute exposures of direct effects to aquatic
organisms. The 1-in-10-year 60-day mean is used for assessing chronic
exposure to fish and aquatic-phase amphibians. The 1-in-10-year 21-day
mean is used for assessing aquatic invertebrate chronic exposure.

[]{.mark}

Exposure estimates for terrestrial animals assumed to be in the target
area or in an area exposed to spray drift are derived using the T-REX
model (version 1.3.1, 12/07/2006). Number range CHAPTERThis model
incorporates the Kenega nomograph, as modified by Fletcher *et al.*
(1994), which is based on a large set of actual field residue data. The
upper limit values from the nomograph represent the 95^th^ percentile of
residue values from actual field measurements (Hoerger and Kenega,
1972). The Fletcher *et al.* (1994) modifications to the Kenega
nomograph are based on measured field residues from 249 published
research papers, including information on 118 species of plants, 121
pesticides, and 17 chemical classes. EECs for terrestrial plants
inhabiting dry and wetland areas are derived using TerrPlant (version
1.2.2, 12/26/2006). This model uses estimates of pesticides in runoff
and in spray drift to calculate EECs. EECs are based upon solubility,
application rate and minimum incorporation depth.

[]{.mark}

The AgDRIFT spray drift model (version 2.01; dated 5/24/2001) is used to
assess exposures of terrestrial plants to profenofos deposited on
terrestrial habitats by spray drift. AgDRIFT will also be used to
determine the appropriate PRZM/EXAMS parameter values for modeling the
percent drift corresponding to the buffers indicated on the label.

##  7.3. Measures of Effect

Ecological effects data are used as measures of direct and indirect
effects to biological receptors. Data are obtained from
registrant-submitted studies or from literature studies identified by
ECOTOX. The ECOTOX database (USEPA 2007*d*) provides more ecological
effects data in an attempt to bridge existing data gaps. ECOTOX is a
source for locating single chemical toxicity data and potential chemical
mixture toxicity data for aquatic life, terrestrial plants, and
wildlife.  ECOTOX was created and is maintained by the USEPA, Office of
Research and Development, and the National Health and Environmental
Effects Research Laboratory\'s Mid-Continent Ecology Division.

Information on the potential effects of profenofos on non-target animals
is also collected from the Ecological Incident Information System (EIIS;
USEPA 2007b). The EIIS is a database containing adverse effect
(typically mortality) reports on non-target organisms where such effects
have been associated with the use of pesticides.

Where available, sublethal effects observed in both registrant-submitted
and open literature studies will be evaluated qualitatively. Such
effects may include behavioral changes (*e.g.*, lethargy and changes in
coloration). Quantitative assessments of risks, though, are limited to
those endpoints that can be directly linked to the Agency's assessment
endpoints of impaired survival, growth and reproduction.

Number range CHAPTERThe assessment of risk for direct effects to
non-target organisms makes the assumption that toxicity of profenofos to
birds is similar to terrestrial-phase amphibians and reptiles. The same
assumption is made for fish and aquatic-phase amphibians.

The acute measures of effect used for animals in this assessment are the
LD~50~, LC~50~ and EC~50~. LD stands for \"Lethal Dose\", and LD~50~ is
the amount of a material, given all at once, that is estimated to cause
the death of 50% of the test organisms. LC stands for "Lethal
Concentration" and LC~50~ is the concentration of a chemical that is
estimated to kill 50% of the test organisms. EC stands for "Effective
Concentration" and the EC~50~ is the concentration of a chemical that is
estimated to produce a specific effect in 50% of the test organisms.
Endpoints for chronic measures of exposure for listed and non-listed
animals are the NOAEL/NOAEC and NOEC. NOAEL stands for "No
Observed-Adverse-Effect-Level" and refers to the highest tested dose of
a substance that has been reported to have no harmful (adverse) effects
on test organisms. The NOAEC (*i.e.*,
"No-Observed-Adverse-Effect-Concentration") is the highest test
concentration at which none of the observed effects were statistically
different from the control. The NOEC is the
No-Observed-Effects-Concentration. For non-listed plants, only acute
exposures are assessed (*i.e.*, EC~25~ for terrestrial plants and EC~50~
for aquatic plants); for listed plants either the NOAEC or EC~05~ is
used.

##  7.4. Integration of Exposure and Effects

Risk characterization is the integration of exposure and ecological
effects characterization to determine the potential ecological risk from
the use of profenofos on cotton and the likelihood of direct and
indirect effects to non-target organisms in aquatic and terrestrial
habitats. The exposure and toxicity effects data are integrated in order
to evaluate the risks of adverse ecological effects on non-target
species. For the assessment of profenofos risks, the risk quotient (RQ)
method is used to compare exposure and measured toxicity values. EECs
are divided by acute and chronic toxicity values. The resulting RQs are
then compared to the Agency's Levels of Concern (LOCs) (USEPA 2004).
These criteria are used to indicate when profenofos's uses, as directed
on the label, have the potential to cause adverse direct or indirect
effects to non-target organisms. In addition, incident data from the
EIIS will be considered as part of the risk characterization.

##  7.5. Deterministic and Probabilistic Assessment Methods

The quantitative assessment of risk will primarily depend on the
deterministic point-estimate based approach described in the risk
assessment. An effort will be made to further qualitatively describe
risk using probabilistic tools that the Agency has developed. These
tools have been reviewed by FIFRA Scientific Advisory Panels
(<http://www.epa.gov/scipoly/sap/index.htm>) and have been deemed as
appropriate means of refining assessments where deterministic approaches
have identified risks.

##  7.6. Endangered Species Assessments

Consistent with the Agency's responsibility under the Endangered Species
Act (ESA), the Agency will evaluate risks to Federally-listed threatened
and/or endangered (listed) species from registered uses of profenofos.
This assessment will be conducted in accordance with the Overview
Document (USEPA 2004), provisions of the ESA, and the Services'
*Endangered Species Consultation Handbook* (USFWS/NMFS, 1998).

The assessment of effects associated with the registration of profenofos
is based on an action area. The action area is considered to be the area
directly or indirectly affected by the federal action, as indicated by
the exceedance of Agency Levels of Concern (LOCs) used to evaluate
direct or indirect effects. The Agency's approach to defining the action
area under the provisions of the Overview Document (USEPA 2004)
considers the results of the risk assessment process to establish
boundaries for that action area with the understanding that exposures
below the Agency's defined LOCs constitute a no-effect threshold. For
the purposes of this assessment, attention will be focused on the
footprint of the action (i.e., the area where profenofos application
occurs), plus all areas where offsite transport (i.e., spray drift,
runoff, etc.) may result in potential exposure that exceeds the Agency's
LOCs. Specific measures of ecological effect that define the action area
for listed species include any direct and indirect effects and/or
potential modification of its critical habitat, including reduction in
survival, growth, and reproduction as well as the full suite of
sublethal effects available in the effects literature. Therefore, the
action area extends to a point where environmental exposures are below
any measured lethal or sublethal effect threshold for any biological
entity at the whole organism, organ, tissue, and cellular level of
organization. In situations where it is not possible to determine the
threshold for an observed effect, the action area is not spatially
limited and is assumed to be the entire United States.

## 7.7. Drinking Water Assessment

A drinking water assessment will be conducted to support future human
health risk assessments of profenofos. The drinking water assessment
will incorporate model estimates of profenofos in surface and ground
waters. Concentrations of profenofos in surface waters will be estimated
using PRZM/EXAMS (see description above). Ground water estimates of
profenofos concentrations will be estimated using the Screening
Concentration in Ground Water (SCI-GROW) model (v.2.3, July 2003). The
drinking water assessment will also include a summary of available
surface and ground water monitoring data.

## 7.8. Preliminary Identification of Data Gaps

###  7.8.1. Fate

The environmental fate data requirements for profenofos are partially
fulfilled with some data gaps still remaining (**Table 5**). Data gaps
include: an aerobic aquatic metabolism half-life and quantification of
leaching and adsorption/desorption of profenofos on various U.S. soils.
The data gaps are discussed below.

+-----+----------------+------+----------+--------+-------------------+
| *   |                |      |          |        |                   |
| *Ta |                |      |          |        |                   |
| ble |                |      |          |        |                   |
| 5.  |                |      |          |        |                   |
| Ava |                |      |          |        |                   |
| ila |                |      |          |        |                   |
| ble |                |      |          |        |                   |
| e   |                |      |          |        |                   |
| nvi |                |      |          |        |                   |
| ron |                |      |          |        |                   |
| men |                |      |          |        |                   |
| tal |                |      |          |        |                   |
| f   |                |      |          |        |                   |
| ate |                |      |          |        |                   |
| d   |                |      |          |        |                   |
| ata |                |      |          |        |                   |
| for |                |      |          |        |                   |
| p   |                |      |          |        |                   |
| rof |                |      |          |        |                   |
| eno |                |      |          |        |                   |
| fos |                |      |          |        |                   |
| and |                |      |          |        |                   |
| rem |                |      |          |        |                   |
| ain |                |      |          |        |                   |
| ing |                |      |          |        |                   |
| d   |                |      |          |        |                   |
| ata |                |      |          |        |                   |
| g   |                |      |          |        |                   |
| aps |                |      |          |        |                   |
| .** |                |      |          |        |                   |
+=====+================+======+==========+========+===================+
| *   | *              | **MR | **       | **Data | **comments**      |
| *Gu | *Description** | ID** | Classifi | Gap?** |                   |
| ide |                |      | cation** |        |                   |
| lin |                |      |          |        |                   |
| e** |                |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Hydrolysis     | 4162 | Ac       | No     | \*MRID 44683901   |
| 5.2 |                | 7309 | ceptable |        | is under review.  |
| 120 |                |      |          |        | This review will  |
|     |                |      |          |        | be completed as   |
|     |                |      |          |        | part of           |
|     |                |      |          |        | registration      |
|     |                |      |          |        | review.           |
|     |                |      |          |        |                   |
|     |                |      |          |        | \*\*MRID 41627311 |
|     |                |      |          |        | was originally    |
|     |                |      |          |        | classified as     |
|     |                |      |          |        | "acceptable" and  |
|     |                |      |          |        | was used to       |
|     |                |      |          |        | fulfill this      |
|     |                |      |          |        | guideline         |
|     |                |      |          |        | requirement.      |
|     |                |      |          |        | Reevaluation of   |
|     |                |      |          |        | this study        |
|     |                |      |          |        | indicates that it |
|     |                |      |          |        | is invalid since  |
|     |                |      |          |        | test soils were   |
|     |                |      |          |        | autoclaved prior  |
|     |                |      |          |        | to treatment with |
|     |                |      |          |        | profenofos.       |
+-----+----------------+------+----------+--------+-------------------+
|     |                | 4193 | Ac       |        |                   |
|     |                | 9001 | ceptable |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Ph             | 4187 | Ac       | No     |                   |
| 5.2 | otodegradation | 9901 | ceptable |        |                   |
| 240 | in water       |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
|     |                | 4193 | Ac       |        |                   |
|     |                | 9002 | ceptable |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Ph             | 4162 | Supp     | No     |                   |
| 5.2 | otodegradation | 7310 | lemental |        |                   |
| 410 | in soil        |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
|     |                | 4468 | Unde     |        |                   |
|     |                | 3901 | termined |        |                   |
|     |                |      | at this  |        |                   |
|     |                |      | time\*   |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Ph             | 4203 | Supp     | No     |                   |
| 5.2 | otodegradation | 0401 | lemental |        |                   |
| 370 | in air         |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Aerobic soil   | 4233 | Ac       | No     |                   |
| 5.4 | metabolism     | 4302 | ceptable |        |                   |
| 100 |                |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Anaerobic soil | 4233 | Ac       | No     |                   |
| 5.4 | metabolism     | 4303 | ceptable |        |                   |
| 200 |                |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Aerobic        | none | none     | *      |                   |
| 5.4 | Aquatic        |      |          | *Yes** |                   |
| 300 | Metabolism     |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Anaerobic      | 4221 | Ac       | No     |                   |
| 5.4 | Aquatic        | 8101 | ceptable |        |                   |
| 400 | Metabolism     |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Leaching and   | none | none     | *      |                   |
| 5.1 | adsorption/    | \*\* |          | *Yes** |                   |
| 230 |                |      |          |        |                   |
|     | desorption     |      |          |        |                   |
| 83  |                |      |          |        |                   |
| 5.1 |                |      |          |        |                   |
| 240 |                |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Laboratory     | 4190 | Supp     | No     |                   |
| 5.1 | Volatility     | 5001 | lemental |        |                   |
| 410 |                |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 83  | Terrestrial    | 4285 | Supp     | No     |                   |
| 5.6 | Field          | 1301 | lemental |        |                   |
| 100 | Dissipation    |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
|     |                | 4290 | Supp     |        |                   |
|     |                | 0901 | lemental |        |                   |
+-----+----------------+------+----------+--------+-------------------+
| 16  | B              | 8    | Supp     | No     |                   |
| 5-4 | ioaccumulation | 5952 | lemental |        |                   |
|     | in Fish        |      |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+
|     |                | 9214 |          |        |                   |
|     |                | 8059 |          |        |                   |
+-----+----------------+------+----------+--------+-------------------+

*Aquatic Metabolism*

Acceptable data have not been provided to quantify the metabolism of
profenofos under aerobic aquatic conditions. According to Code of
Federal Regulations 40 (CFR40 2007) Part 158 Subpart D (data
requirements for pesticides) aerobic aquatic metabolism are required for
pesticides with terrestrial uses. Since profenofos use on cotton is
considered to be terrestrial, aerobic aquatic metabolism data for
profenofos should be submitted to fulfill OPPTS Guideline 835.4300.
These data are used to estimate the degradation of profenofos in aquatic
systems and ultimately to derive aquatic EECs using PRZM/EXAMS. In the
case that these data are unavailable at the time risk assessments are
conducted, PRZM/EXAMS input parameter guidance default values will be
employed to account for aerobic aquatic metabolism (See **Table A.1. of
Appendix A**).

*Leaching and Adsorption/Desorption*

At this time, there are no acceptable studies to quantify the adsorption
and desorption characteristics of profenofos in U.S. soils. EFED
recommends that the Special Review and Reregistration Division (SRRD)
request the submission of an acceptable study under OPPTS Guideline
835.1230 to define K~d~ and K~OC~ values of profenofos in U.S. soils. In
the absence of these data, EFED will assume that there is no sorption of
profenofos to soils or organic matter on the treatment site. In order to
implement this in derivation of aquatic EECs, a K~OC~ value of 0 will be
used to parameterize PRZM/EXAMS. Input of a K~OC~ value \>0 is expected
to result in lower aquatic EECs. If acceptable data are provided, the
uncertainties associated with this assumption will be reduced.

### 7.8.2. Effects

Although many submissions have been made to provide data on the effects
of profenofos to aquatic and terrestrial organisms, several data gaps
still exist (**Tables 6 -- 8**). Data gaps include the following: avian
acute oral toxicity, early-life stage estuarine/marine fish toxicity,
and aquatic plant growth studies. The data gaps are discussed below.

+-----+--------------+-------+----------+-------+--------------------+
| *   |              |       |          |       |                    |
| *Ta |              |       |          |       |                    |
| ble |              |       |          |       |                    |
| 6.  |              |       |          |       |                    |
| Ava |              |       |          |       |                    |
| ila |              |       |          |       |                    |
| ble |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| col |              |       |          |       |                    |
| ogi |              |       |          |       |                    |
| cal |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| ffe |              |       |          |       |                    |
| cts |              |       |          |       |                    |
| d   |              |       |          |       |                    |
| ata |              |       |          |       |                    |
| for |              |       |          |       |                    |
| te  |              |       |          |       |                    |
| rre |              |       |          |       |                    |
| str |              |       |          |       |                    |
| ial |              |       |          |       |                    |
| a   |              |       |          |       |                    |
| nim |              |       |          |       |                    |
| als |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| xpo |              |       |          |       |                    |
| sed |              |       |          |       |                    |
| to  |              |       |          |       |                    |
| p   |              |       |          |       |                    |
| rof |              |       |          |       |                    |
| eno |              |       |          |       |                    |
| fos |              |       |          |       |                    |
| and |              |       |          |       |                    |
| rem |              |       |          |       |                    |
| ain |              |       |          |       |                    |
| ing |              |       |          |       |                    |
| d   |              |       |          |       |                    |
| ata |              |       |          |       |                    |
| g   |              |       |          |       |                    |
| aps |              |       |          |       |                    |
| .** |              |       |          |       |                    |
+=====+==============+=======+==========+=======+====================+
| *   | **D          | **MR  | **       | *     | **Comments**       |
| *Gu | escription** | ID/** | Classifi | *Data |                    |
| ide |              |       | cation** | G     |                    |
| lin |              | **A   |          | ap?** |                    |
| e** |              | ccess |          |       |                    |
|     |              | ion** |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Avian oral   | 41627 | Ac       | **Ye  | \*Avian acute oral |
| 0.2 | toxicity     | 301\* | ceptable | s\*** | toxicity data are  |
| 100 |              |       |          |       | not available for  |
|     |              |       |          |       | passerines, which  |
|     |              |       |          |       | are required under |
|     |              |       |          |       | the new 40 CFR     |
|     |              |       |          |       | Part 158. An acute |
|     |              |       |          |       | oral toxicity      |
|     |              |       |          |       | study using        |
|     |              |       |          |       | passerines must be |
|     |              |       |          |       | submitted to       |
|     |              |       |          |       | fulfill this data  |
|     |              |       |          |       | requirement.       |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Supp     |       |                    |
|     |              | 99113 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Avian        | 000   | Supp     | No    |                    |
| 0.2 | dietary      | 99114 | lemental |       |                    |
| 200 | toxicity     |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 431   | Ac       |       |                    |
|     |              | 07302 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 431   | Ac       |       |                    |
|     |              | 07301 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 99115 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Avian        | 000   | Supp     | No    |                    |
| 0.2 | reproduction | 72150 | lemental |       |                    |
| 300 |              |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 83076 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 86661 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Honeybee     | 416   | Ac       | No    |                    |
| 0.3 | acute        | 27308 | ceptable |       |                    |
| 020 | contact      |       |          |       |                    |
|     | toxicity     |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+

+-----+--------------+-------+----------+-------+--------------------+
| *   |              |       |          |       |                    |
| *Ta |              |       |          |       |                    |
| ble |              |       |          |       |                    |
| 7.  |              |       |          |       |                    |
| Ava |              |       |          |       |                    |
| ila |              |       |          |       |                    |
| ble |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| col |              |       |          |       |                    |
| ogi |              |       |          |       |                    |
| cal |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| ffe |              |       |          |       |                    |
| cts |              |       |          |       |                    |
| d   |              |       |          |       |                    |
| ata |              |       |          |       |                    |
| for |              |       |          |       |                    |
| a   |              |       |          |       |                    |
| qua |              |       |          |       |                    |
| tic |              |       |          |       |                    |
| a   |              |       |          |       |                    |
| nim |              |       |          |       |                    |
| als |              |       |          |       |                    |
| e   |              |       |          |       |                    |
| xpo |              |       |          |       |                    |
| sed |              |       |          |       |                    |
| to  |              |       |          |       |                    |
| p   |              |       |          |       |                    |
| rof |              |       |          |       |                    |
| eno |              |       |          |       |                    |
| fos |              |       |          |       |                    |
| and |              |       |          |       |                    |
| rem |              |       |          |       |                    |
| ain |              |       |          |       |                    |
| ing |              |       |          |       |                    |
| d   |              |       |          |       |                    |
| ata |              |       |          |       |                    |
| g   |              |       |          |       |                    |
| aps |              |       |          |       |                    |
| .** |              |       |          |       |                    |
+=====+==============+=======+==========+=======+====================+
| *   | **D          | **    | **       | *     | **comments**       |
| *Gu | escription** | MRID/ | Classifi | *Data |                    |
| ide |              | A     | cation** | G     |                    |
| lin |              | ccess |          | ap?** |                    |
| e** |              | ion** |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Freshwater   | 4009  | Supp     | No    | \*A saltwater fish |
| 0.1 | fish --      | 80101 | lemental |       | early-life stage   |
| 075 |              |       |          |       | test (850.1400) is |
|     | Acute        |       |          |       | required for       |
|     | toxicity     |       |          |       | profenofos because |
|     |              |       |          |       | the acute toxicity |
|     |              |       |          |       | value for          |
|     |              |       |          |       | saltwater fish is  |
|     |              |       |          |       | \< 1 mg/L.         |
|     |              |       |          |       |                    |
|     |              |       |          |       | \*\*A freshwater   |
|     |              |       |          |       | fish full          |
|     |              |       |          |       | life-cycle test    |
|     |              |       |          |       | (835.1500) was     |
|     |              |       |          |       | requested for      |
|     |              |       |          |       | profenofos based   |
|     |              |       |          |       | on the 2006 IRED;  |
|     |              |       |          |       | however, a waiver  |
|     |              |       |          |       | was granted for    |
|     |              |       |          |       | this request,      |
|     |              |       |          |       | given that an      |
|     |              |       |          |       | acceptable early   |
|     |              |       |          |       | life stage         |
|     |              |       |          |       | freshwater fish    |
|     |              |       |          |       | study is           |
|     |              |       |          |       | available.         |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | TN    | Supp     |       |                    |
|     |              | 2399  | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 83075 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Supp     |       |                    |
|     |              | 85953 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 72148 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Supp     |       |                    |
|     |              | 85958 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 72149 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | TN    | Ac       |       |                    |
|     |              | 2400  | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Saltwater    | 000   | Ac       | No    |                    |
| 0.1 | fish --      | 85960 | ceptable |       |                    |
| 075 |              |       |          |       |                    |
|     | Acute        |       |          |       |                    |
|     | toxicity     |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Freshwater   | 416   | Ac       | No    |                    |
| 0.1 | i            | 27304 | ceptable |       |                    |
| 010 | nvertebrates |       |          |       |                    |
|     | --           |       |          |       |                    |
|     |              |       |          |       |                    |
|     | Acute        |       |          |       |                    |
|     | toxicity     |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Supp     |       |                    |
|     |              | 85964 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 001   | Supp     |       |                    |
|     |              | 08015 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 2     | Supp     |       |                    |
|     |              | 52706 | lemental |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Saltwater    | 000   | Ac       | No    |                    |
| 0.1 | i            | 85963 | ceptable |       |                    |
| 025 | nvertebrates |       |          |       |                    |
|     | --           |       |          |       |                    |
| 85  |              |       |          |       |                    |
| 0.1 | Acute        |       |          |       |                    |
| 035 | toxicity     |       |          |       |                    |
|     |              |       |          |       |                    |
| 85  |              |       |          |       |                    |
| 0.1 |              |       |          |       |                    |
| 045 |              |       |          |       |                    |
|     |              |       |          |       |                    |
| 85  |              |       |          |       |                    |
| 0.1 |              |       |          |       |                    |
| 055 |              |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 85961 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 85959 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
|     |              | 000   | Ac       |       |                    |
|     |              | 85962 | ceptable |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Freshwater   | 000   | Ac       | No    |                    |
| 0.1 | invertebrate | 85964 | ceptable |       |                    |
| 300 | --           |       |          |       |                    |
|     |              |       |          |       |                    |
|     | life cycle   |       |          |       |                    |
|     | test         |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Saltwater    | 000   | Ac       | No    |                    |
| 0.1 | i            | 85963 | ceptable |       |                    |
| 350 | nvertebrates |       |          |       |                    |
|     | --           |       |          |       |                    |
|     |              |       |          |       |                    |
|     | life cycle   |       |          |       |                    |
|     | test         |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Freshwater   | 000   | Ac       | No    |                    |
| 0.1 | fish --      | 85958 | ceptable |       |                    |
| 400 |              |       |          |       |                    |
|     | early life   |       |          |       |                    |
|     | stage test   |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Saltwater    | None  | Not      | **Ye  |                    |
| 0.1 | fish --      |       | Ap       | s\*** |                    |
| 400 |              |       | plicable |       |                    |
|     | early life   |       |          |       |                    |
|     | stage test   |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+
| 85  | Fish --      | None  | Not      | N     |                    |
| 0.1 |              |       | Ap       | o\*\* |                    |
| 500 | life cycle   |       | plicable |       |                    |
|     | test         |       |          |       |                    |
+-----+--------------+-------+----------+-------+--------------------+

  ---------------------------------------------------------------------------------------------------
  **Table 8.                                                                    
  Available                                                                     
  ecological                                                                    
  effects data                                                                  
  for plants                                                                    
  exposed to                                                                    
  profenofos and                                                                
  remaining data                                                                
  gaps.**                                                                       
  --------------- ----------------- ---------- -------------------- ----------- ---------------------
  **Guideline**   **Description**   **MRID**   **Classification**   **Data      **comments**
                                                                    Gap?**      

  850.4100        Terrestrial Plant None       Not applicable       No          \*Non-target aquatic
                  toxicity: Tier I                                              plant data are
                  seedling                                                      required for
                  emergence                                                     profenofos at the
                                                                                Tier 1 level.

  850.4225        Terrestrial Plant 41627307   Acceptable           No          
                  toxicity: Tier 2                                              
                  seedling                                                      
                  emergence                                                     

  850.4150        Terrestrial Plant None       Not applicable       No          
                  toxicity: Tier I                                              
                  vegetative vigor                                              

  850.4150        Terrestrial Plant 41627305   Acceptable           No          
                  toxicity: Tier 2                                              
                  vegetative vigor                                              

  850.4400        Aquatic Plant     None       Not applicable       **Yes\***   
                  Growth: algae                                                 

  850.4400        Aquatic Plant     None       Not applicable       **Yes\***   
                  Growth: vascular                                              
                  plants                                                        
  ---------------------------------------------------------------------------------------------------

*Avian Acute Oral Toxicity*

Acceptable acute avian oral toxicity data were submitted for exposures
of mallard duck to profenofos; however, data are not available for
passerines, which are required under the new 40 CFR Part 158 (CFR 40
2007) data requirements for conventional pesticides (72 FR 60934; USEPA
2007c). The new Part 158 data requirements specify that acute avian oral
toxicity data be submitted for either a mallard duck or bobwhite quail
AND a passerine species. Based on the results of previous ecological
risk assessments for profenofos and derivation of preliminary RQs in
this problem formulation (Section 6 and Appendix B), risks are expected
for non-listed and listed birds due to acute exposures to profenofos.
Therefore, an avian oral toxicity test (OPPTS Guideline 850.2100;
http://www.epa.gov/opptsfrs/publications/OPPTS_Harmonized/850_Ecological_Effects_Test_Guidelines/Drafts/850-2100.pdf)
is required for passerine birds, as specified in 40 CFR Part 158 (CFR40
2007). EFED suggests that SRRD request submission of a passerine study
protocol for review by the Agency prior to initiation of this study. If
oral acute toxicity data are not submitted for passerines, EFED will
assume acute risk for passerine species.

*Chronic Toxicity Studies with Estuarine and Marine Fish*

Chronic toxicity data are not available for estuarine and marine fish.
In the absence of these data, an acute-to-chronic ratio (ACR) would
normally be derived; and the chronic toxicity to estuarine and marine
fish would be estimated based on the ACR for freshwater fish. However,
an ACR cannot be derived because the freshwater fish data necessary for
calculating the ACR are not available. Chronic data are not available
for the most acutely sensitive freshwater species (bluegill sunfish;
*Lepomis macrochirus*), and definitive acute data are not available for
the most chronically sensitive freshwater species (fathead minnow).
Based on the results of previous ecological risk assessments for
profenofos and derivation of preliminary aquatic RQs in this problem
formulation (Section 6 and Appendix A), risks are expected for
non-listed and listed fish due to chronic exposures to profenofos in
aquatic habitats. In addition, the majority of reported ecological
incidents associated with the use of profenofos have involved fish
kills. Therefore, an estuarine/marine fish early life-stage toxicity
test (OPPTS Guideline 850.1400;
http://www.epa.gov/opptsfrs/publications/OPPTS_Harmonized/850_Ecological_Effects_Test_Guidelines/Drafts/850-1400.pdf)
is required in order to fulfill the data requirement. In the absence of
chronic toxicity data for estuarine and marine fish, EFED will assume
chronic risk to these taxa.

*Aquatic Plant Studies*

Toxicity data for vascular and non-vascular aquatic plants are not
available. Based on the 40 CFR Part 158 data requirements, Tier I level
non-target aquatic plant data are required for all insecticides. In
addition, available data for non-target terrestrial plants show impacts
to cucumber seedling emergence at a concentration less than the maximum
single application rate for profenofos. Therefore, this data gap must be
filled, and non-target aquatic plant data for algae and vascular plants
(OPPTS Guideline 850.4400;
http://www.epa.gov/opptsfrs/publications/OPPTS_Harmonized/850_Ecological_Effects_Test_Guidelines/Drafts/850-4400.pdf)
are required for profenofos at the Tier 1 level. In the absence of Tier
I data, EFED will assume risk to both vascular and non-vascular aquatic
plants.

# 8. References

CFR 40. 2007. Code of Federal Regulations 40 Parts 150 to 189.
Protection of the Environment. U.S. Government Printing Office.

Fletcher, J.S., J.E. Nellessen, and T.G. Pfleeger. 1994. Literature
review and evaluation of the EPA food-chain (Kenaga) nomogram, an
instrument for estimating pesticide residues on plants. Environ. Tox.
Chem. 13:1383-1391.

Number range CHAPTERHoerger, F. and E. E. Kenaga, 1972. Pesticide
Residues on Plants: Correlation of Representative Data as a Basis for
Estimation of their Magnitude in the Environment. [In]{.underline} F.
Coulston and F. Korte, eds., *Environmental Quality and Safety:
Chemistry, Toxicology, and Technology,* Georg Thieme Publ., Stuttgart,
West Germany, pp. 9-28.

Mayer, F.; Ellersieck, M. 1986. *Manual of Acute Toxicity:
Interpretation and Data Base 410 Chemicals and 66 Species of Fresh-Water
Animals*. US Fish & Wildlife Service; Resource Publication (160): 579 p.

U.S.Department of Agriculture (USDA). 2007. National Agricultural
Statistics Service. United States Department of Agriculture. Available
online at: <http://www.nass.usda.gov/>.

U.S. Environmental Protection Agency (USEPA). 1998. Guidelines for
Ecological Risk Assessment. Risk Assessment Forum, Office of Research
and Development, Washington, D.C. EPA/630/R-95/002F. April 1998.
<http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=30759>

USEPA. 2000. Interim Registration Eligibility Decision (IRED):
Profenofos. U.S. Environmental Protection Agency, Office of Pesticide
Programs, Washington, DC. August, 2000.

USEPA. 2002. Guidance for Selecting Input Parameters in Modeling the
Environmental Fate and Transport of Pesticides, Version II. US
Environmental Protection Agency, Washington DC. Online at:
http://www.epa.gov/oppefed1/models water/input_guidance2_28_02.htm.

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the
Office of Pesticide Programs. U.S. Environmental Protection Agency,
Office of Prevention, Pesticides and Toxic Substances, Office of
Pesticide Programs, Washington DC. January 23, 2004.

USEPA. 2006. Reregistration Eligibility Decision (IRED): Profenofos.
U.S. Environmental Protection Agency, Office of Pesticide Programs,
Washington, DC. July, 2006.

USEPA. 2007a. Profenofos: transmittal of section 18 for profenofos to
control rice panicle mite on rice in Texas. U.S. Environmental
Protection Agency, Office of Pesticide Programs, Washington, DC.
September 2007.

USEPA. 2007b. Ecological Incident Information System.
<http://www.epa.gov/espp/consultation/ecorisk-overview.pdf>

USEPA. 2007c. 40 CFR Part 158. Pesticides; Data Requirements for
Conventional Chemicals: Final Rule. 72 FR 60934. October 26, 2007.

USEPA. 2007*d*. ECOTOXicology Database. Office of Research and
Development National Health and Environmental Effects Research
Laboratory's (NHEERL's) Mid-Continent Ecology Division (MED).
<http://cfpub.epa.gov/ecotox/>

U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries
Service (NMFS). 1998. Endangered Species Consultation Handbook:
Procedures for Conducting Consultation and Conference Activities Under
Section 7 of the Endangered Species Act. Final Draft. March 1998.

[SUBMITTED FATE STUDIES:]{.underline}

[MRID]{.underline}

000859‑52 Cargile, N.L., and J.E. Cassidy. 1977. The metabolism of
o‑^14^C‑CGA‑15324 in bluegill sunfish. Report No. ABR‑77076. Unpublished
study performed and submitted by Ciba‑Geigy Corporation, Greensboro, NC.

416273‑09 Ziegler, D.A., and S.A. Hallenbeck. 1988. Hydrolysis of
profenofos in aqueous solutions. Laboratory Project ID 1091A.
Unpublished study performed by Analytical Development Corporation,
Colorado Springs, CO, and submitted by Ciba‑Geigy Corporation,
Greensboro, NC.

416273‑10 Das, Y.T. 1989a. Photodegradation of
\[phenyl(U)^14^C\]profenofos on soil under artificial sunlight.
Laboratory Project Number ISSI No. 89131. Unpublished study performed by
Innovative Scientific Services, Inc., Piscataway, NJ, and submitted by
Ciba‑Geigy Corporation, Greensboro, NC.

416273‑11 Yu, W.C. 1987. Determination of adsorption/desorption
constants of profenofos. Laboratory Project Study Number 14300.
Unpublished study performed by Cambridge Analytical Associates, Inc.,
Boston, MA and submitted by Ciba‑Geigy Corporation, Greensboro, NC.

418799‑01 Das, Y.T. 1989b. Photodegradation of
\[phenyl(U)‑^14^C\]profenofos in aqueous solution buffered at pH 5 under
artificial sunlight. Laboratory Project No. 89132. Unpublished study
performed by Innovative Scientific Services, Inc., Piscataway, NJ, and
submitted by Ciba‑Geigy Corporation, Greensboro, NC.

419050‑01 Carpenter, M. 1991. Laboratory volatility of ^14^C‑profenofos.
ABC Laboratories\' No. 39119. Ciba‑Geigy Protocol No. 141‑90.
Unpublished study performed by ABC Laboratories, Columbia, MO; submitted
by Ciba‑Geigy Corporation, Greensboro, NC.

419390‑01 Das, Y.T. 1990a. Hydrolysis of \[phenyl(U)‑^14^C\]profenofos
in aqueous solutions buffered at pH 5, 7, and 9. Laboratory Project No.
90122. Ciba‑Geigy Protocol No. 146‑90. Unpublished study performed by
Innovative Scientific Services, Inc., Piscataway, NJ, and submitted by
Ciba‑Geigy Corporation, Greensboro, NC.

419390‑02 Das, Y.T. 1990b. Photodegradation of
\[phenyl(U)‑^14^C\]profenofos in aqueous solution buffered at pH 5 under
artificial sunlight. Laboratory Project No. 90121. Ciba‑Geigy Protocol
No. 147‑90. Unpublished study performed by Innovative Scientific
Services, Inc., Piscataway, NJ, and submitted by Ciba‑Geigy Corporation,
Greensboro, NC.

420304‑01 Kieatiwong, S. 1991. Photodegradation of \[^14^C\]‑profenofos
in the vapor phase by natural sunlight. Laboratory Project ID: PTRL
Project No. 310W. Ciba‑Geigy Protocol No. 12‑91. Unpublished study
performed by Pharmacology and Toxicology Research Laboratory, Richmond,
CA, and submitted by Ciba‑Geigy Corporation, Greensboro, NC.

422181‑01 Das, Y. T. 1992a. Metabolism of \[phenyl(U)‑^14^C\]profenofos
under anaerobic aquatic soil conditions. ISSI No. 90123, Ciba‑Geigy
Study No. 156‑90. Unpublished study performed by Innovative Scientific
Services, Inc., Piscataway, NJ, and submitted by Ciba‑Geigy Corporation,
Greensboro, NC.

423343‑02 Das, Y.T. 1992b. Metabolism of \[phenyl(U)‑^14^C\]profenofos
under aerobic soil conditions. ISSI No. 91030; Ciba‑Geigy Study No.
18‑91. Unpublished study performed by Innovative Scientific Services,
Inc., Piscataway, NJ, and submitted by Ciba‑Geigy Corporation,
Greensboro, NC.

423343‑03 Das, Y. T. 1991. Metabolism of \[phenyl(U)‑^14^C\]profenofos
under anaerobic soil conditions. ISSI No. 91031, Ciba‑Geigy Study No.
19‑91. Unpublished study performed by Innovative Scientific Services,
Inc., Piscataway, NJ, and submitted by Ciba‑Geigy Corporation,
Greensboro, NC.

428513‑01 Selman, F., and Larson, M. 1993a. Terrestrial Dissipation of
Profenofos (Curacron 8E) on Bareground and Cotton in California.
Unpublished study performed by Pan-Agricultural Laboratories, Inc.,
Madera, CA and Agricultural & Priority Pollutants Laboratories, Inc.,
Fresno, CA; submitted by Ciba Plant Protection, Greensboro, NC.

429009‑01 Selman, F., and Larson, M. 1993b. Terrestrial Dissipation of
Profenofos (Curacron 8E) on Bareground and Cotton in Texas. An
unpublished study performed by Pan-Agricultural Laboratories, Inc.
Madera, CA and Enseco‑Cal Labs, West Sacramento, CA and submitted by
Ciba Plant Protection, Greensboro, NC.

921480‑59 Swidersky, P. 1990. Phase 3 summary of MRID 00085952: The
metabolism of 0-^14^C‑CGA‑15324 in bluegill sunfish: Project MI2‑130‑4F.
Report No. ABR‑77076. Unpublished study performed by Ciba‑Geigy
Corporation, Greensboro, NC and EG & G Bionomics, Wareham, MA.

[SUBMITTED EFFECTS STUDIES:]{.underline}

000721-46 Ciba-Geigy Corporation (1978) Commentary and Reports of
Investigations Made with Respect to the Environmental Safety of Curacron
(CGA-15324, Profenfos) to Wildlife. Summary of studies 237826-B through
237826-H. (Unpublished study received Mar 20, 1979 under 100-598;
CDL:237826-A).

000859-58 LeBlanc, G.A.; Hoberg, J.R.; Dean, J.W. (1979) The Toxicity of
CGA- 15324 to Fathead Minnow (*Pimephales promelas*) Eggs and Fry:
Report #BW-79-6-490. (Unpublished study received Nov 6, 1981 under
100-598; prepared by EG & G, Bionomics, submitted by Ciba- Geigy Corp.,
Greensboro, N.C.; CDL:246216-L).

000859-60 Heitmuller, T. (1980) Acute Toxicity of Profenofos to Pinfish
(*Lagodon rhomboides*): Report No. BP-80-2-35. (Unpublished study
received Nov 6, 1981 under 100-598; prepared by EG & G, Bionomics,
submitted by Ciba-Geigy Corp., Greensboro, N.C.; CDL: 246216-N).

000859-63 Hollister, T.A. (1980) Acute and Chronic Toxicity of
Profenofos to Mysid Shrimp (*Mysidopsis bahia*): Report No. BP-80-2-40.
(Unpublished study received Nov 6, 1981 under 100-598; prepared by EG &
G, Bionomics, submitted by Ciba-Geigy Corp., Greensboro, N.C.;
CDL:246216-Q).

000859-64 LeBlanc, G.A.; Surprenant, D.C. (1980) The Chronic Toxicity of
CGA- 15234 to the Water Flea (*Daphnia magna*): Report #BW-80-2- 611.
(Unpublished study received Nov 6, 1981 under 100-598; prepared by EG &
G, Bionomics, submitted by Ciba-Geigy Corp., Greensboro, N.C.;
CDL:246216-R).

000866-61 Fink, R.; Beavers, J.B. (1978) Final Report: One-generation
Repro- duction Study\--Bobwhite Quail: CGA-15324 Technical: Project No.
108-151. (Unpublished study received Nov 6, 1981 under 100- 598;
prepared by Wildlife International, Ltd., submitted by Ciba-Geigy Corp.,
Greensboro, N.C.; CDL:246218-AB)

001052-26 Bathe, R. (1974) Acute Oral LD50 of Technical CGA-15324 in the
Mouse: Project No. Siss 3647. (Unpublished study received Feb 14, 1979
under 100-598; prepared by Ciba-Geigy, Ltd., Switz., submitted by
Ciba-Geigy Corp., Greensboro, NC; CDL:097794-F).

001052-42 Ciba-Geigy Corp. (1979) Follow-up to EPA Meeting of November
13, 1978, on Curacron Potential For Chronic Exposure to Aquatic
Organisms: Report No. ABR-79026. (Compilation; unpublished study
received Mar 20, 1979 under 100-598; CDL:237827.

416273-01 Pedersen, C. (1990) Profenofos Technical: 21-Day Acute Oral
LD50 Study in Mallard Ducks: Lab Project Number: 89 DD 75. Unpub- lished
study prepared by Bio-Life Associates, Ltd. 40 p.

416273-04 Bellantoni, D. (1990) Profenofos Technical: A 48-Hour Static
Acute Toxicity Test with the Cladoceran (Daphnia magna): Lab Project
Number: 108A. Unpublished study prepared by Wildlife Interna- tional
Ltd. 20 p.

416273-05 Chetram, R. (1990) Profenofos: Tier 2 Vegetative Vigor
Nontarget Phytotoxicity Study using Profenofos Technical (Curacron): Lab
Project Number: LR90-408. Unpublished study prepared by Pan-
Agricultural Laboratories, Inc. 133 p.

416273-07 Chetram, R. (1990) Profenofos: Tier 2 Seedling Emergence
Notarget Phytotoxicity Study using Profenofos Technical (Curacron): Lab
Project Number: LR90-410. Unpublished study prepared by Pan-
Agricultural Laboratories, Inc. 135 p.

416273-08 Winter, P. (1990) Profenofos: An Acute Contact Toxicity Study
with the Honey Bee: Lab Project Number: 108-321. Unpublished study
prepared by Wildlife International Ltd. 17 p.

431073-01 Brewer, L.; Taliaferro, L. (1994) Profenofos Technical: CGA
15324: Eight-Day Dietary LC50 Study in Northern Bobwhite: Lab Project
Number: 019301. Unpublished study prepared by Ecotoxicity and Biosystems
Associates, Inc. 108 p.

431073-02 Taliaferro, L. (1994) Profenofos Technical: CGA 15324:
Eight-Day Dietary LC50 Study in the Mallard Duck: Lab Project Number:
019302. Unpublished study prepared by Ecotoxicity and Biosystems
Associates, Inc. 110 p.

432133-08 Minor, J.; Richter, A. (1994) A Two-Generation Reproduction
Study in Rats with CGA-15324 Technical: Final Report: Lab Project
Number: F-00102. Unpublished study prepared by Ciba-Geigy Corp.,
Environmental Health Center. 822 p.

432133-09 Gilles, P. (1994) A Two-Generation Reproduction Study in Rats
with CGA-15324 Technical: Amendment 1 to Final Report: Lab Project
Number: F-00102. Unpublished study prepared by Ciba-Geigy Corp.,
Environmental Health Center. 9 p.

921480-04 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085810. One Generation Reproduction Study of Profenofos (CGA-15324) in
Bobwhite Quail: Report No. 108-173. Prepared by WILDLIFE INTERNATIONAL
LTD. 24 p.

921480-06 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00072150. One Generation Reproduction Study of Profenofos (CGA-15324) in
Mallard Duck: Report No. 108-153. Prepared by WILDLIFE INTERNATIONAL
LTD. 21 p.

921480-08 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00083075. Acute Toxicity of Profenofos (CGH 15324) Technical to Bluegill
(Lepomis macrochirus): Report No. BW-78-12-371. Prepared by EG &G
Bionomics. 16 p.

921480-09 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00072149. Acute Toxicity of Profenofos (CGA-15324) Technical to Rainbow
Trout (Salmo gairdneri): Report No. BW-79-1-382. Prepared by EG &G
Bionomics. 18 p.

921480-10 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085960. Acute Toxicity of Profenofos (CGA-15324) to Pinfish (Lagodon
rhomboides): Report No. BP-80-2-35. Prepared by EG & G Bionomics Marine
Research Lab. 17 p.

921480-11 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085962. Acute Toxicity of Profenofos to Eastern Oysters (Crassostrea
virginica): Report No. BP-80-2-37. Prepared by EG & G Bionomics Marine
Research Lab. 18 p.

921480-12 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085961. Acute Toxicity of Profenofos to Pink Shrimp (Penaeous
duorarum): Report No. BP-80-2-36. Prepared by EG & G Bionomics Marine
Research Lab. 17 p.

921480-13 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085964. Chronic Toxicity of Profenofos Technical to Daphnia magna
under Flow-through Conditions: Report No. BW-80-2-611. Prepared by EG&G
Bionomics. 20 p.

921480-14 Plautz, J. (1990) Ciba-Geigy Corp. Phase 3 Summary of MRID
00085958. Toxicity of Profenofos (CGA-15324) Technical to Fathead Minnow
(*Pimephales promelas*): Report No. BW-79-6-490. Prepared by EG&G
Bionomics. 17 p.

#  APPENDIX A: Preliminary EECs for aquatic habitats and RQs for aquatic organisms.

PRZM (v3.12.2, May 2005) and EXAMS (v2.98.4.6, April 2005) are
simulation models. These models are run using the input shell pe5.pl
(Aug 2007) to generate daily exposures and 1-in-10 year estimated
environmental concentrations (EECs) for profenofos. The conceptual model
for exposure represents surface water bodies adjacent to application
sites receiving profenofos through runoff and spray drift. PRZM
simulates pesticide application, movement and transformation on an
agricultural field and the resultant pesticide loadings to a receiving
water body via runoff, erosion and spray drift. EXAMS simulates the fate
of the pesticide and resulting concentrations in the water body. The
standard scenario used for ecological pesticide assessments assumes
application to a 10-hectare agricultural field that drains into an
adjacent 1-hectare water body, 2-meters deep (20,000 m^3^ volume) with
no outlet. PRZM/EXAMS was used to estimate screening-level exposure of
aquatic organisms to profenofos. The measure of exposure for aquatic
species is the 1-in-10 year return peak or rolling mean concentration.
The 1-in-10 year peak is used for estimating acute exposures of direct
effects to the CRLF, as well as indirect effects to the CRLF through
effects to potential prey items, including: algae, aquatic
invertebrates, fish and frogs. The 1-in-10-year 60-day mean is used for
assessing chronic exposure to the CRLF and fish and frogs serving as
prey items; the 1-in-10-year 21-day mean is used for assessing chronic
exposure for aquatic invertebrates, which are also potential prey items.
Input parameters for PRZM/EXAMS and the resulting EECs are in **Tables
A.1 and A.2**, respectively.

[]{.mark}

[]{.mark}

+--------------------------------+---------+---------------------------+
| **Table A.1. PRZM/EXAMS input  |         |                           |
| parameters.**                  |         |                           |
+================================+=========+===========================+
| **Input Parameter**            | **      | **Justification**         |
|                                | Value** |                           |
+--------------------------------+---------+---------------------------+
| **Chemical specific**          |         |                           |
+--------------------------------+---------+---------------------------+
| Molecular Wt. (g/mol)          | 373.63  | Product chemistry data    |
+--------------------------------+---------+---------------------------+
| Solubility in water (mg/L at   | 200     | 10X solubility^1^         |
| 25^o^C)                        |         |                           |
+--------------------------------+---------+---------------------------+
| Vapor pressure (torr)          | 3.46    | Product chemistry data    |
|                                | x10^-6^ |                           |
+--------------------------------+---------+---------------------------+
| Henry's Law Constant           | 2.38 x  | Product chemistry data    |
| (atm-m^3^/mol)                 | 10^‑7^  |                           |
+--------------------------------+---------+---------------------------+
| Koc (mL/g~oc~)                 | 0       | Since no acceptable data  |
|                                |         | are available, Koc is     |
|                                |         | assumed to be 0.          |
+--------------------------------+---------+---------------------------+
| Aerobic Soil Metabolism        | 9       | 3X available value (3d)   |
| Half-life (days)               |         | ^1^                       |
+--------------------------------+---------+---------------------------+
| Aerobic Aquatic Metabolism     | 4.5     | 0.5X aerobic soil         |
| Half-life (days)               |         | metabolism half-life      |
|                                |         | parameter value (9 d) ^1^ |
+--------------------------------+---------+---------------------------+
| Anaerobic Aquatic Metabolism   | 12      | 3X available value (4d)   |
| Half-life (days)               |         | ^1^                       |
+--------------------------------+---------+---------------------------+
| Hydrolysis Half-life (days)    | 62      | Longest hydrolysis rate   |
|                                |         | available for pH 7        |
+--------------------------------+---------+---------------------------+
| Aqueous Photolysis Half-life   | 0       | Assume stable^1^          |
| (days)                         |         |                           |
+--------------------------------+---------+---------------------------+
| **Use specific**               |         |                           |
+--------------------------------+---------+---------------------------+
| Chemical application method    | 2       | Foliar applications       |
| (CAM)                          |         |                           |
+--------------------------------+---------+---------------------------+
| Application rate (kg/ha)       | 1.12    | (for 2 applications per   |
|                                |         | season)                   |
|                                | 0.84    |                           |
|                                |         | (for 6 applications per   |
|                                |         | season, plus one          |
|                                |         | application at 0.56       |
|                                |         | kg/ha)                    |
+--------------------------------+---------+---------------------------+
| Application efficiency         | 0.95    | Aerial application        |
+--------------------------------+---------+---------------------------+
| Spray drift fraction           | 0.024   | For aerial applications,  |
|                                |         | the label indicates that  |
|                                |         | applications cannot be    |
|                                |         | made within 300 ft of any |
|                                |         | body of water. This       |
|                                |         | reduces estimates of      |
|                                |         | spray drift to 2.4%       |
|                                |         | (according to Tier I      |
|                                |         | modeling with AgDRIFT).   |
+--------------------------------+---------+---------------------------+
| Application interval (days)    | 5       | Label instructions        |
|                                |         |                           |
|                                |         | (registration 100-669)    |
+--------------------------------+---------+---------------------------+
| Initial application date       | July 1  | Within the crop growing   |
|                                |         | period for all 4 PRZM     |
|                                |         | cotton scenarios.         |
+--------------------------------+---------+---------------------------+
| ^1^According to input          |         |                           |
| parameter guidance for         |         |                           |
| PRZM/EXAMS (USEPA 2002).       |         |                           |
+--------------------------------+---------+---------------------------+

[]{.mark}

[]{.mark}

[]{.mark}

[]{.mark}

[]{.mark}

+----------------------+--------------+----------------+--------------+
| **Table A.2.         |              |                |              |
| Preliminary aquatic  |              |                |              |
| EECs for aerial      |              |                |              |
| applications of      |              |                |              |
| profenofos to        |              |                |              |
| cotton.**            |              |                |              |
+======================+==============+================+==============+
| **PRZM scenario**    | **Peak EEC** | **21-day EEC** | **60-day     |
|                      |              |                | EEC**        |
|                      | **(1-in-10   | **(1-in-10     |              |
|                      | year)**      | year)**        | **(1-in-10   |
|                      |              |                | year)**      |
+----------------------+--------------+----------------+--------------+
| **2 aerial           |              |                |              |
| applications per     |              |                |              |
| year at 1 lb a.i./A  |              |                |              |
| (1.12 kg/ha)**       |              |                |              |
+----------------------+--------------+----------------+--------------+
| CA cotton STD        | 4.61         | 1.68           | 0.790        |
+----------------------+--------------+----------------+--------------+
| MS cotton STD        | 35.1         | 9.04           | 3.31         |
+----------------------+--------------+----------------+--------------+
| NC cotton STD        | 13.6         | 6.12           | 2.59         |
+----------------------+--------------+----------------+--------------+
| TX cotton OP         | 41.6         | 36.2           | 28.4         |
+----------------------+--------------+----------------+--------------+
| **6 aerial           |              |                |              |
| applications per     |              |                |              |
| year at 0.75 lb      |              |                |              |
| a.i./A (0.84 kg/ha)  |              |                |              |
| plus one application |              |                |              |
| at 0.5 lb a.i./A     |              |                |              |
| (0.56 kg/ha)**       |              |                |              |
+----------------------+--------------+----------------+--------------+
| CA cotton STD        | 13.4         | 4.96           | 2.34         |
+----------------------+--------------+----------------+--------------+
| MS cotton STD        | 42.4         | 15.8           | 7.97         |
+----------------------+--------------+----------------+--------------+
| NC cotton STD        | 26.4         | 11.2           | 5.26         |
+----------------------+--------------+----------------+--------------+
| TX cotton OP         | 67.4         | 18.9           | 7.11         |
+----------------------+--------------+----------------+--------------+

  -------------------------- ----------------------------- --------------
  Table A.3. Agency Levels                                 
  of Concern (LOCs).                                       

  **Risk Presumption**       **Taxa**                      **LOC**

  Acute Risk                 Birds, mammals, aquatic       0.5
                             animals                       

                             Plants                        1

  Acute Restricted Use       Birds, mammals                0.2

                             Aquatic animals               0.1

  Acute Endangered Species   Birds, mammals                0.1

                             Aquatic animals               0.05

                             Plants                        1

  Chronic Risk               Birds, mammals, aquatic       1
                             animals                       
  -------------------------- ----------------------------- --------------

[]{.mark}

[]{.mark}

  ------------------ ----------- ------------- ------------- --------------
  **Table A.4.                                               
  Preliminary RQs                                            
  for freshwater                                             
  fish and                                                   
  invertebrates.**                                           

  **Scenario**       **Acute     **Chronic     **Acute       **Chronic
                     Fish^1^**   Fish ^2^**    Invert ^3^**  Invert ^4^**

  **2 aerial                                                 
  applications per                                           
  year at 1 lb                                               
  a.i./A (1.12                                               
  kg/ha)**                                                   

  CA cotton STD      0.327       0.395         5.0           8.4

  MS cotton STD      2.489       1.655         37.7          45.2

  NC cotton STD      0.965       1.295         14.6          30.6

  TX cotton OP       2.950       14.2          44.7          181

  **6 aerial                                                 
  applications per                                           
  year at 0.75 lb                                            
  a.i./A (0.84                                               
  kg/ha) plus one                                            
  application at 0.5                                         
  lb a.i./A (0.56                                            
  kg/ha)**                                                   

  CA cotton STD      0.950       1.17          14.4          24.8

  MS cotton STD      3.007       3.985         45.6          79

  NC cotton STD      1.872       2.63          28.4          56

  TX cotton OP       4.780       3.555         72.5          94.5

  1 Based on LC50 =                                           
  14.1 ug/L for                                              
  bluegill sunfish.                                          

  2 Based on NOAEC =                                          
  2.0 ug/L for                                               
  fathead minnow.                                            

  3 Based on EC50 =                                           
  0.93 ug/L for                                              
  waterflea.                                                 

  4 Based on NOAEC =                                          
  0.2 ug/L for                                               
  waterflea.                                                 
  ------------------ ----------- ------------- ------------- --------------

  ------------------ ----------- ------------- ------------- --------------
  **Table A.5.                                               
  Preliminary RQs                                            
  for                                                        
  estuarine/marine                                           
  fish and                                                   
  invertebrates.**                                           

  **Scenario**       **Acute     **Chronic     **Acute       **Chronic
                     Fish^1^**   Fish ^2^**    Invert ^3^**  Invert ^4^**

  **2 aerial                                                 
  applications per                                           
  year at 1 lb                                               
  a.i./A (1.12                                               
  kg/ha)**                                                   

  CA cotton STD      0.599       NA            1.9           7.64

  MS cotton STD      4.558       NA            14.6          41.1

  NC cotton STD      1.766       NA            5.7           27.8

  TX cotton OP       5.403       NA            17.3          164.5

  **6 aerial                                                 
  applications per                                           
  year at 0.75 lb                                            
  a.i./A (0.84                                               
  kg/ha) plus one                                            
  application at 0.5                                         
  lb a.i./A (0.56                                            
  kg/ha)**                                                   

  CA cotton STD      1.740       NA            5.6           22.5

  MS cotton STD      5.506       NA            17.7          71.8

  NC cotton STD      3.429       NA            11.0          50.9

  TX cotton OP       8.753       NA            28.1          85.9

  1 Based on LC50 =                                           
  7.7 ug/L for                                               
  pinfish.                                                   

  2 Chronic toxicity                                          
  data are not                                               
  available for                                              
  estuarine/marine                                           
  fish.                                                      

  3 Based on EC50 =                                           
  2.4 ug/L for mysid                                         
  shrimp.                                                    

  4 Based on NOAEC =                                          
  0.22 ug/L for                                              
  mysid shrimp.                                              
  ------------------ ----------- ------------- ------------- --------------

# APPENDIX B: Preliminary EECs and associated RQs for terrestrial mammals and birds

**B.1. Terrestrial animals**

[]{.mark}

The T-REX model (version 1.3.1) is used to calculate dietary and
dose-based EECs of profenofos for mammals and birds. Exposure to mammals
and birds is based on the maximum application rate and minimum interval
between applications, according to the registered profenofos label for
cotton. Input values for T-REX are located in **Table B.1**. Upper-bound
Kenega nomogram values are utilized to derive EECs for profenofos
exposures to terrestrial mammals and birds based on dietary- and
dose-based exposures (**Table B.2**). A 1-year time period is simulated.
Consideration is given to different types of feeding strategies for
mammals and birds, including herbivores, insectivores and granivores.
For dose-based exposures, three weight classes of mammals (15, 35 and
1000 g) and birds (20, 100, and 1000 g) are considered. Toxicity values
used to define effects to mammals and birds from acute and chronic
exposures are described in the effects characterization section of this
document.

[]{.mark}

+-------------------------------------------------+--------------------+
| **Table B.1. Input parameters for deriving      |                    |
| terrestrial EECs for profenofos using T-REX.**  |                    |
+-------------------------------------------------+--------------------+
| **Parameter Description**                       | **Value**          |
+-------------------------------------------------+--------------------+
| Application Rate (lbs a.i./A)                   | 1^a^               |
+-------------------------------------------------+--------------------+
| Foliar Half-life (days)                         | 1.3^b^             |
+-------------------------------------------------+--------------------+
| Application Interval (days)                     | 5                  |
+-------------------------------------------------+--------------------+
| Number of Applications                          | 2^a^               |
+-------------------------------------------------+--------------------+
| ^a^ Based on 2 applications @ 1.0 lb a.i./A.    |                    |
|                                                 |                    |
| ^b^ 1.3-day foliar half-life (based on the      |                    |
| 90^th^ percentile of the foliar dissipation     |                    |
| half-lives for profenofos in Willis and         |                    |
| McDowell (1986).                                |                    |
+-------------------------------------------------+--------------------+

[]{.mark}

+--------------------+-------+------+------+------+------+------+------+
| **Table B.2. T-REX |       |      |      |      |      |      |      |
| calculated EECs of |       |      |      |      |      |      |      |
| profenofos on food |       |      |      |      |      |      |      |
| residues.**        |       |      |      |      |      |      |      |
+--------------------+-------+------+------+------+------+------+------+
| **Food Type**      | **    | **   |      |      | **   |      |      |
|                    | Dieta | Dose |      |      | Dose |      |      |
|                    | ry-Ba | -Bas |      |      | -Bas |      |      |
|                    | sed** | ed** |      |      | ed** |      |      |
|                    |       |      |      |      |      |      |      |
|                    | **(p  | **   |      |      | **   |      |      |
|                    | pm)** | (mg/ |      |      | (mg/ |      |      |
|                    |       | kg-b |      |      | kg-b |      |      |
|                    | **(ma | w)** |      |      | w)** |      |      |
|                    | mmals |      |      |      |      |      |      |
|                    | and   | *    |      |      | **(  |      |      |
|                    | bir   | *(ma |      |      | bird |      |      |
|                    | ds)** | mmal |      |      | s)** |      |      |
|                    |       | s)** |      |      |      |      |      |
+--------------------+-------+------+------+------+------+------+------+
|                    | **All | *    | **   | *    | *    | **   | *    |
|                    | Size  | *Sma | Medi | *Lar | *Sma | Medi | *Lar |
|                    | Clas  | ll** | um** | ge** | ll** | um** | ge** |
|                    | ses** |      |      |      |      |      |      |
|                    |       | *    | *    | **(  | *    | **   | **(  |
|                    |       | *(15 | *(35 | 1000 | *(20 | (100 | 1000 |
|                    |       | g)** | g)** | g)** | g)** | g)** | g)** |
+--------------------+-------+------+------+------+------+------+------+
| Short Grass        | 2     | 24   | 16   | 3    | 29   | 16   | 7    |
|                    | 56.69 | 4.73 | 9.14 | 9.22 | 2.34 | 6.71 | 4.64 |
+--------------------+-------+------+------+------+------+------+------+
| Tall Grass         | 1     | 11   | 7    | 1    | 13   | 7    | 3    |
|                    | 17.65 | 2.17 | 7.52 | 7.97 | 3.99 | 6.41 | 4.21 |
+--------------------+-------+------+------+------+------+------+------+
| Broadleaf          | 1     | 13   | 9    | 2    | 16   | 9    | 4    |
| plants/sm insects  | 44.39 | 7.66 | 5.14 | 2.06 | 4.44 | 3.77 | 1.98 |
+--------------------+-------+------+------+------+------+------+------+
| Fruits/pods/lg     | 16.04 | 1    | 1    | 2.45 | 1    | 1    | 4.66 |
| insects            |       | 5.30 | 0.57 |      | 8.27 | 0.42 |      |
+--------------------+-------+------+------+------+------+------+------+
| Seeds (granivore)  | 16.04 | 3.40 | 2.35 | 0.54 | 1    | 1    | 4.66 |
|                    |       |      |      |      | 8.27 | 0.42 |      |
+--------------------+-------+------+------+------+------+------+------+

[]{.mark}

Acute dose-based RQs for mammals are derived using the reported LD~50~
298 mg/kg. The acute listed species LOC of 0.1 is exceeded for small and
medium-sized mammals ([\<]{.underline} 35 g) that feed on short and tall
grass, broadleaf plants, fruits, pods, and small insects, as well as
large mammals (1000 g) that feed on short grass, broadleaf plants and
small insects, based on acute, dose-based exposures of mammals to
profenofos (**Table B.3**). Chronic dietary-based RQs for mammals are
derived using the reported NOAEC of 100 ppm (mg/kg-diet). Chronic
dose-based RQs are calculated using the NOAEL of 7.3 mg/kg-bw/day. For
chronic dietary- and dose-based exposures, the chronic LOC is exceeded
for all mammal size classes that feed on short and tall grass, broadleaf
plants, and small insects (**Table B.4**).

[]{.mark}

+---------------------+---------------+--------------+----------------+
| **Table B.3. Acute  |               |              |                |
| RQs for mammals of  |               |              |                |
| different size and  |               |              |                |
| feeding classes.**  |               |              |                |
+---------------------+---------------+--------------+----------------+
| **Food Type**       | **Dose-Based  |              |                |
|                     | RQs**         |              |                |
+---------------------+---------------+--------------+----------------+
|                     | **Small (15   | **Medium (35 | **Large (1000  |
|                     | g)**          | g)**         | g)**           |
+---------------------+---------------+--------------+----------------+
| Short Grass         | **0.37^a^**   | **0.32^a^**  | **0.17**       |
+---------------------+---------------+--------------+----------------+
| Tall Grass          | **0.17**      | **0.15**     | \<0.10         |
+---------------------+---------------+--------------+----------------+
| Broadleaf plants/sm | **0.21^a^**   | **0.18**     | **0.10**       |
| insects             |               |              |                |
+---------------------+---------------+--------------+----------------+
| Fruits/pods/lg      | \<0.10        | \<0.10       | \<0.10         |
| insects             |               |              |                |
+---------------------+---------------+--------------+----------------+
| Seeds (granivore)   | \<0.10        | \<0.10       | \<0.10         |
+---------------------+---------------+--------------+----------------+
| Bolded RQs values   |               |              |                |
| [\>]{.underline}    |               |              |                |
| acute endangered    |               |              |                |
| species LOC of 0.1. |               |              |                |
|                     |               |              |                |
| ^a^ RQ value        |               |              |                |
| [\>]{.underline}    |               |              |                |
| acute restricted    |               |              |                |
| use LOC of 0.2.     |               |              |                |
+---------------------+---------------+--------------+----------------+

[]{.mark}

  ------------------ ----------------- -------------- ------------ ---------------
  **Table B.4.                                                     
  Chronic RQs for                                                  
  mammals of                                                       
  different size and                                               
  feeding classes.**                                               

  **Food Type**      **Dietary-Based   **Dose-Based                
                     RQs**             RQs**                       

                     **All Size        **Small (15    **Medium (35 **Large (1000
                     Classes**         g)**           g)**         g)**

  Short Grass        **2.57**          **15.25**      **13.03**    **6.98**

  Tall Grass         **1.18**          **6.99**       **5.97**     **3.20**

  Broadleaf          **1.44**          **8.58**       **7.33**     **3.93**
  plants/sm insects                                                

  Fruits/pods/lg     0.16              0.95           0.81         0.44
  insects                                                          

  Seeds (granivore)  0.16              0.21           0.18         0.10

  Bolded values                                                    
  [\>]{.underline}                                                 
  chronic LOC of                                                   
  1.0.                                                             
  ------------------ ----------------- -------------- ------------ ---------------

[]{.mark}

Acute dose-based RQ values are calculated using the value available for
the mallard duck (LD~50~ = 55 mg a.i./kg-bw). The acute endangered
species LOC of 0.1 is exceeded for all size classes and feeding types of
birds, with the exception of large birds that eat fruits, pods, seeds,
and large insects. In addition, the acute risk LOC of 0.5 is exceeded
for all feeding types for the small 20 g bird and for medium and large
sized birds (100 to 1000 g) that consume short and tall grass, broadleaf
plants, and small insects. (**Table B.5**).

[]{.mark}

+--------------------------+-------------+-------------+-------------+
| **Table B.5. Dose-based  |             |             |             |
| RQ values for acute      |             |             |             |
| exposures to birds.**    |             |             |             |
+--------------------------+-------------+-------------+-------------+
| **Food Type**            | **20 g**    | **100 g**   | **1000 g**  |
+--------------------------+-------------+-------------+-------------+
| Short Grass              | **1         | **          | **          |
|                          | 0.24^a,b^** | 4.59^a,b^** | 1.45^a,b^** |
+--------------------------+-------------+-------------+-------------+
| Tall Grass               | **          | **          | **          |
|                          | 4.69^a,b^** | 2.10^a,b^** | 0.67^a,b^** |
+--------------------------+-------------+-------------+-------------+
| Broadleaf plants/sm      | **          | **          | **          |
| insects                  | 5.76^a,b^** | 2.58^a,b^** | 0.82^a,b^** |
+--------------------------+-------------+-------------+-------------+
| Fruits/pods/seeds/lg     | **          | **0.29^a^** | 0.09        |
| insects                  | 0.64^a,b^** |             |             |
+--------------------------+-------------+-------------+-------------+
| Bolded RQs values        |             |             |             |
| [\>]{.underline} acute   |             |             |             |
| endangered species LOC   |             |             |             |
| of 0.1.                  |             |             |             |
|                          |             |             |             |
| ^a^ RQ value             |             |             |             |
| [\>]{.underline} acute   |             |             |             |
| restricted use LOC of    |             |             |             |
| 0.2.                     |             |             |             |
|                          |             |             |             |
| ^b^ RQ value             |             |             |             |
| [\>]{.underline} acute   |             |             |             |
| risk LOC of 0.5.         |             |             |             |
+--------------------------+-------------+-------------+-------------+

[]{.mark}

Acute dietary-based RQ values, which are calculated using the LC~50~ for
bobwhite quail (57 mg/kg-diet), exceed the acute endangered species LOC
for all feeding types and the acute risk LOC for birds that feed on
short and tall grass, broadleaf plants, and small insects. Chronic
dietary-based RQ values are calculated using the bobwhite quail NOAEC
(\<1 mg/kg-diet). Although definitive chronic avian RQs could not be
derived, the chronic risk LOC is exceeded birds consuming all types of
food items (**Table B.6**).

[]{.mark}

+-------------------------------------+--------------+----------------+
| **Table B.6. Acute and chronic,     |              |                |
| dietary-based RQ s for birds by     |              |                |
| food type.**                        |              |                |
+-------------------------------------+--------------+----------------+
| **Food Type**                       | **Acute RQ** | **Chronic RQ** |
+-------------------------------------+--------------+----------------+
| Short Grass                         | *            | **\>256.69**   |
|                                     | *4.50^a,b^** |                |
+-------------------------------------+--------------+----------------+
| Tall Grass                          | *            | **\>117.65**   |
|                                     | *2.06^a,b^** |                |
+-------------------------------------+--------------+----------------+
| Broadleaf plants/small insects      | *            | **\>144.39**   |
|                                     | *2.53^a,b^** |                |
+-------------------------------------+--------------+----------------+
| Fruits/pods/seeds/large insects     | **0.28^a^**  | **\>16.04**    |
+-------------------------------------+--------------+----------------+
| Bolded acute RQ values              |              |                |
| [\>]{.underline} endangered species |              |                |
| LOC of 0.1; bolded chronic RQ       |              |                |
| values [\>]{.underline} chronic LOC |              |                |
| of 1.0.                             |              |                |
|                                     |              |                |
| ^a^ Acute RQ value [\>]{.underline} |              |                |
| acute restricted use LOC of 0.2.    |              |                |
|                                     |              |                |
| ^b^ Acute RQ value [\>]{.underline} |              |                |
| acute risk LOC of 0.5.              |              |                |
+-------------------------------------+--------------+----------------+

# APPENDIX C: Preliminary EECs and associated RQs for terrestrial and riparian plants 

The TerrPlant model (version 1.2.2) is used to calculate EECs for
non-target plant species inhabiting dry and semi-aquatic areas (**Table
C.1**). Selected model parameters include: an application rate of 1.0
lbs a.i./A to represent the maximum single application rate of
profenofos; and a runoff value of 0.02 (selected based on profenofos
solubility, which is 20 mg/L). EECs for these crops correspond to aerial
and ground application methods, which assume 5% and 1% spray drift,
respectively. EECs relevant to terrestrial plants consider pesticide
concentrations in drift and in runoff. Since TerrPlant does not consider
multiple applications, exposures could be underestimated in cases where
plants are exposed through multiple applications of profenofos. Based on
the single maximum aerial or ground application rate of profenofos, the
LOC is exceeded for non-listed and listed species of dicots inhabiting
semi-aquatic areas (**Table C.2**). No adverse effects were observed in
any of the four tested monocots at the highest test concentration (1.0
lb a.i./A) of profenofos in the seedling emergence and vegetative vigor
plant studies; therefore, risks are not expected for terrestrial monocot
plant species.

[]{.mark}

  -----------------------------------------------------------------------
  **Table C.1. EECs                                       
  (lbs a.i./A)                                            
  generated by                                            
  TERRPLANT (v. 1.2.2)                                    
  for evaluation of                                       
  exposure of dry and                                     
  semi-aquatic area                                       
  plants to                                               
  profenofos.**                                           
  --------------------- ---------------- ---------------- ---------------
  **Use Pattern**       **Loading to     **Loading to     **Drift**
                        adjacent dry     semi-aquatic     
                        areas**          areas**          

  Cotton (aerial)       0.07             0.25             0.05

  Cotton (ground)       0.03             0.21             0.01
  -----------------------------------------------------------------------

  -------------- ----------------- --------- ------------------ --------------
  **Table C.2.                                                  
  RQ values for                                                 
  plants in dry                                                 
  and                                                           
  semi-aquatic                                                  
  areas exposed                                                 
  to profenofos                                                 
  through runoff                                                
  and/or spray                                                  
  drift.\***                                                    

  **Plant Type** **Listed Status** **Dry**   **Semi-Aquatic**   **Spray
                                                                Drift**

  Dicot          non-listed        0.23      **1.62\***         \<0.1

  Dicot          listed            0.27      **1.91\***         \<0.1

  \*If RQ \>                                                    
  1.0, the LOC                                                  
  is exceeded,                                                  
  resulting in                                                  
  potential for                                                 
  risk to that                                                  
  plant group.                                                  
  -------------- ----------------- --------- ------------------ --------------