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## Environmental Fate and Ecological Risk Assessment for the Registratio n Review of Profenofos

Profenofos

O

- (4

- bromo

- 2

- chlorophenyl) O

- ethyl S

- propyl phosphorothioate

CAS Registry Number 41198

- 08

- 7

PC Code 111401

Prepared by:

Michelle Colletti, Chemist Michael Wagman, Biologist William P. Eckel, Ph.D. , Senior Scienc e Advisor, ERB VI

U. S. Environmental Protection Agency Office of Pesticide Programs

Environmental Fate and Effects Division

Environmental Risk Branch VI 1200 Pennsylvania Ave., NW

Mail Code 7507P Washington DC 20460 Reviewed by:

Nathan Miller

, Biolog ist , ERB VI

Paul Mastradone, Senior Chemist, EISB

Mark Corbin, Branch Chief, ERB VI

September 15 , 2015Page 4 of 75



## Table of Contents

1. Executive Summary

................................ ................................ ................................ ................................ ................. 5

2. Problem Formulation

................................ ................................ ................................ ................................ ............ 12

2.1. Nature of Regulatory Action

................................ ................................ ................................ ....................... 12

2.2. Mode of Action

................................ ................................ ................................ ................................ .............. 12

2.3. Use Characterization

................................ ................................ ................................ ................................ .... 12

2.4. Conceptual Model

................................ ................................ ................................ ................................ ......... 14 3. Analysis

................................ ................................ ................................ ................................ ................................ ... 20 3.1. Exposure Characterization

................................ ................................ ................................ ................................ 20 3.2. Ecological Effects Characterization

................................ ................................ ................................ .................. 26

4. Risk Characterization

................................ ................................ ................................ ................................ ........... 35

4.1. Risk Estimation

................................ ................................ ................................ ................................ ................... 35 4.2. Risk Description

................................ ................................ ................................ ................................ .................. 39

5. Federally Threatened and Enda ngered (Listed) Species Concerns

................................ ............................. 44

5.1. Action Area

................................ ................................ ................................ ................................ ................... 46

5.2. Taxonomic Groups Potentially at Risk

................................ ................................ ................................ ....... 46

6. Literature Cited

................................ ................................ ................................ ................................ ..................... 48 Appendix A

– Summary of Risk Conclusions by Taxa

................................ ................................ ......................... 50 Appendix B

— Input Parameters and Output for the STIR model

................................ ................................ .... 51 Appendix C

— Chemical Structure and Characteristics of Profenofos Degradates

................................ ......... 53 Appendix D . Example Input and Outputs for the SIP Model

................................ ................................ ........... 55 Appendix E. Example Input and Outputs for the KABAM Model

................................ ................................ . 56 Appendix F. Predictive Data for Parent Profenofos and its Degradates from QSAR Modeling using

ECOSAR v1.11

................................ ................................ ................................ ................................ ....................... 62 Appendix G. Length of Time for Profenofos Residues to Decrease Below LOCs after Application.

............. 68 Appendix H. AgDrift Analysis of Spray Drift Effects to Off

- field Organisms.

................................ ............... 75Page 5 of 75

1. Executive Summary

EFED has completed the Registration Review draft ecological risk assessment for profenofos

. Profenofos is an insecticide /miticide belonging to the organophosphate class of pesticid es

. Profenofos is registered for use only on cotton and must be applied by enclosed cab ground application equipment. It is used to control cotton bollworm, tobacco budworm, and certain other insects, and mites. The only currently registered end

- use pro duct, Curacron ® 8E Insecticide

Miticide (EPA Reg No. 100

- 669) , is an emulsifiable concentrate that is diluted with water and/or vegetable oil. Current label restrictions prohibit profenofos applications within 100 feet of any body of water and treating cr ops within 14 days of harvest when diluted with water or 30 days

when diluted with oil.

Profenofos is fairly non

- persistent and degrades primarily by microbial metabolism as well as the abiotic process of hydrolysis. Degradation from hydrolysis varies with pH, with half

- lives ranging

from less than a day for alkaline (pH 9) waters to over 100 days for acidic (pH 5) water s

. Although not highly mobile, profenofos may reach surface waters through spray drift or runoff. Profenofos is not likely to volatil ize

.

The major degradates tracked in submitted studies appear to have limited toxicity compared with the parent profenofos. O

- ethyl

- S

- propyl phosphorothioate was not tracked in the submitted studies through radiolabeling and no empirical information on i ts fate or toxicity is available

. This degradate may degrade further into O

- ethyl phosphate and 1

- propanethiol.

Risk Conclusions

Aquatic Organisms Multiple lines of evidence indicate potential for risk to aquatic organisms. These includ e the modeled exp osure values, ecotoxicity information, and incident data. This assessment considered the toxicity of parent profenofos only, but Quantitative Structure Activity Relationship (QSAR) analysis indicates that certain degradates for which empirical data are not available, may have toxicity approaching the parent, al though the stability of these degradates is uncertain. If these degradates are stable, th e n risk to fish may be greater than presented in this assessment

.

KABAM analysis indicates that profenofos ha s the potential to bioaccumulate, and cause adverse

effects to bird s and mammals that consume fish, especially on a chronic basis.

Aquatic Invertebrates

T here is potential for acute and chronic risk to both listed and non

- listed species of

freshwater and estuarine/marine aquatic invertebrates. Acute RQs range from 4.3 to 11.3 while chronic RQs range from 23

— 25

. Incident data confirm the hazard to aquatic

invertebrates. No sediment toxicity studies were available to evaluate the risk of profenofos to be nthic inv ertebrates in the sediment ; however

, since the maximum benthic

pore water estimated environmental concentrations ( EECs ) are approximately an order of magnitude lower than water column EECs and risk to aquatic invertebrates is already

indicated wit h the available data, the lack of sediment toxicity data is not considered aPage 6 of 75

major data gap. Modeled benthic pore water concentrations however are sufficiently high enough that listed and non

- listed species of benthic invertebrates would likely be

conside red to be at risk if they are of similar sensitivity as other aquatic invertebrates for

which data is available.

AgDrift analysis indicates that the spray drift of profenofos residues have the potential to adversely impact listed aquatic invertebra te spe cies habitating water bodies at distances between 265 feet (using low booms and nozzles producing coarser droplet spectra) and 810 feet (using high booms and nozzles producing finer droplet spectra) from the edge of the application area.

Fish There is p otential for acute and chronic risk to both listed and non

- listed species of freshwater and estuarine/marine fish (and aquatic

- phase amphibians, for which fish are considered surrogates). Acute RQs range from 0.73 to 1.34 , while chronic RQs range

from 12 to 21 . Incident data confirm the hazard to fish. Current labeling, which specifies hazards to fish and restricts application near water, may address this risk concern to some degree.

Aquatic Plants

P otential for risk to listed and non

- listed speci es of vascular plants is unlikely. Although there is some uncertainty regarding the toxicity of profenofos to non

- vascular plants, the screening

- level risk assessment indicates that risk to this tax on is also unlikely and the

lack of this data is not cons idered a major data gap for the risk assessment.

Terrestrial Organisms The screening

- level risk assessment for birds and mammals uses conservative assumptions such

as a default half

- life value for foliar dissipation and conservative acute avian toxicity e ndpoints.
However, e ven when refined assessment measures are used, the potential for risk persists overall

for these taxa

, al though not all terrestrial animals would be considered to be at risk.

Birds

T here is potential for acute and chronic risk to b oth listed and non

- listed avian species ( as well as reptiles and terrestrial

- phase amphibians, for which birds are considered surrogates). Acute RQs range from 0.18 to 92 while chronic RQs range from >50 to
>800

. Chronic risk to birds is likely to be hig her than assessed in this risk assessment due to the quantitative use of the lowest observed adverse effects concentration ( LOAEC )

in lieu of a no observed adverse effects concentration ( NOAEC ) due to the ( nondefinitive ( i.e. “less tha n”) nature of the NO AEC. A major data gap in the risk assessment is t he lack of a chronic dietary dose concentration that does not result in effects to birds

.

AgDrift analysis indicates that profenofos residues from spray drift have the potential to adversely impact off

- fi eld listed birds species at distances between 15 feet feet (using low booms and nozzles producing coarser droplet spectra) and 125 feet (using high booms and nozzles producing finer droplet spectra) from the edge of the application area.Page 7 of 75

Mammals

T here is potential for acute and chronic risk to both listed and non

- listed species of

mammals. Acute RQs range from 0.01 to 2.25 while chronic RQs range from 6 to 951

.

Beneficial Terrestrial Invertebrates

T here is potential for acute and chronic risk to both listed and non

- listed species of beneficial terrestrial invertebrates based on acute contact exposure to residues from spray drift or from direct application when applications are made and beneficial invertebrates

are present. As this pesticide is an inse cticide/ acaricide, it is also likely to have effects on

beneficial terrestrial invertebrates. The acute contact RQ for honey bees on the field exposed to profenofos through spray droplets is 14.2. The current label language may mitigate risk from acute c ontact basis to honey bees because it prohibits treatment while bees are foraging in/or adjacent to the treatment area. However, other, non

- Apis bees and other beneficial insects may still be at risk

, as their presence may be less conspicuous to the pesti cide applicator. Additionally, dietary risk to both adult and juvenile life stages of

terrestrial invertebrates cannot be precluded due to the lack of acute and chronic oral data

with adult and larval honey bees , which is considered a major data gap in th e risk

assessment.

AgDrift analysis indicates that profenofos residues from spray drift have the potential to adversely impact non

- listed off

- field terrestrial invertebrates at distances between 10 feet (using low booms and nozzles producing coarser drop let spectra) and 90 feet (using high booms and nozzles producing finer droplet spectra) from the edge of the application area.

Terrestrial Plants The results of this screening

- level risk assessment indicate that the current use of profenofos is not expec ted to cause direct adverse effects to listed and non

- listed terrestrial plants. Although there is some uncertainty regarding the toxicity of profenofos formulations to the vegetative vigor of terrestrial plants, the screening

- level risk

assessment indica tes that risk to this tax on is unlikely and the lack of vegetative vigor data with a typical end

- use product (TEP) is not considered a major data gap for the risk

assessment. There is some potential for risk to listed species occurring on the agricultural

field as application rates are higher than the endpoints from the available seedling emergence study

.

Incident Reports

From 1989 to 1999

, there were 23 incidents reported where fish or aquatic invertebrates suffered mortalities and profenofos was consid ered to be at least a “possible” cause of the incident. The incident data provide additional lines of evidence for risk conclusions to aquatic fish and

invertebrates.Page 8 of 75

D esignations of “uncertain” for taxa in this assessment are a result o f incomplete eco toxicology

data. Where uncertainty designations are made for a taxon, efforts have been made to

characterize the risk picture. For instance, multiple lines of evidence support the potential for

effects to fish and aquatic invertebrates , whereas for nonvas cular aquatic plants , available lines

of evidence indicat e that the potential for risk may be low er

.

Table 1 summarizes the taxa that may potentially be directly at r isk from exposure to profenofos

. Additional description is further summarized in Appendi x A

.

Table 1 : Summary of Risk Determinations for Profenofos 1

U se Fish 2 Aquatic

Invertebrates 3 Aquatic

Plants 4 Terrestrial Plants Birds 5 Mammals Terrestrial

Invertebrates Acute Chronic Acute Chronic Listed NonListed Monocots Di cots Acute Chronic Acute Chronic Acute Chronic Listed Non - Listed Listed Non

Listed

Cotton X X X X X X X X X U a

1 A bolded and shaded “ X ” indicates risk is expected to listed and non

- listed species. A “U” indicates that risk is uncert ain due to a lack of data. A blank box indicates that no risk is expected. See Risk Characterization section for more information. 2 Fish includes both estuarine/marine and freshwater fish and are also considered surrogates for aquatic

- phase amphibians. 3 Aquatic Invertebrates includes both

estuarine/marine and freshwater invertebrates. 4 Aquatic Plants includes both vascular and non

- vascular plants. 5 Birds are considered surrogates for reptiles and terrestrial

- phase amphibians.

a Chronic risk is un certain due to a lack of chronic oral data for adult and juvenile honey bees.

Potential effects to federally

- listed endangered and threatened species (listed species) based on LOC exceedances require an in

- depth listed species evaluation determining the p otential co

occurrence of listed species and use pattern of profenofos. Only species in cotton

- growing areas are expected to be at risk of exposure. Identified potential risks to listed species are summarized

in Table 2.

Table 2. Potential Effects to F ederally Listed Taxa Associated with Direct Effects from the Registered Use of Profenofos.

Listed Plant Taxon Potential Direct Effects

Terrestrial and semi

- aquatic plants

– monocots and dicots No

Aquatic nonvascular plants 1 No Aquatic vascular plants No

Listed Animal Taxon Potential Direct Effects

Acute Chronic

Terrestrial invertebrates Yes Uncertain 2

Mammals Yes Yes

Birds Yes Yes Reptiles Yes Yes Amphibians 3 Yes Yes

Freshwater fish Yes Yes

Freshwater invertebrates Yes Yes

Estuarine/marine fi sh Yes Yes

Estuarine/marine invertebrates Yes Yes

1 There are currently no listed species of aquatic non

- vascular plants.Page 9 of 75 2 Chronic risk to listed species of terrestrial invertebrates is uncertain due to the lack of chronic data for juvenile and adu lt

ho ney bees.

3 Acute and chronic risk to this taxa is expected for both the terrestrial and aquatic

- phase in the amphibian life cycle.Page 10 of 75

Basic Uncertainties

 The r isk assessment is based on parent profenofos only. E mpirical ecotoxic icity data are only avai lable for the degradate

, 4

- bromo

- 2

- chlorophenol effects’ to aquatic non

- vascular plants . Th erefore, th is assessment uses QSAR to characterize potential risk from other profenofos degradates. There is some evidence that certain degradates have toxicity

ap proaching that of parent profenofos, but their stability is uncertain and their inclusion would not change any risk conclusions.

 Chirality of the compound creates uncertainty around the fate characterisitcs ( i.e. microbial degradation) and ecotoxicity of the compound. Therefore, the assessment may underestimate or overestimate the potential risk posed by the use of profenofos . None of the submitted data addressed the issue of chirality or identify which chiral isomer was used in each study

.

 Aerobic Aqu atic Metabolism (OCSPP Guideline 835.4300). No q uantitatively acce ptable

data are available for aerobic aquatic metabolism

. Therefore, e stimates for modeling

were based on defaults derived from the EFED Input Parameter Guidance (EFED, 2009).

 Dislodgeabl e Foliar Residue Data on Cotton (OCSPP Guideline 875.2100). This

assessment assumed the default foliar dissipation half

- live of 35 day s . A limited amount of data indicates that profenofos residues may dissipate at a substantially faster rate (~1 day)

. H owever, EFED needs 3 separate foliar dissipation half

- lives in order to use an

alternate half

- life quantitatively in the risk assessment. The limited empirical data are used qualitatively to characterize risk in the assessment. A dditional d islodgeable fo liar

residue data would decrease uncertainties associated with the use of the default half

- life.

 Non

- vascular aquatic plant testing (OCSPP Guidelines 850.4500 and 850.4550) . No acceptable data are available for green algae, blue

- green algae

, n or freshwat er or saltwater diatoms. The a vailable qualitatively supplemental data on green algae indicate

that non

- vascular aquatic plants may be more sensitive than vascular aquatic plants, for

which acceptable data are available. Given that the data indicate that profenofos is substantially less toxic to aquatic plants than other taxa ( e.g. aquatic invertebrates) and would need to be considerably (at least 1 order of magnitude) more toxic to non

- vascular plants than to vascular plants in order to create a risk conc ern for non

- vascular aquatic plants , this is considered a minor data gap.

 For avian reproduction (OCSPP Guideline 850. 2300) , concentrations tested were not sufficiently low to achieve a NOAEC

. This assessment has used the lowest dose from that study (th e LOAEC) in the risk assessment quantitatively in lieu of the NOAEC.

A vian chronic risk quotients are thus uncertain and therefore this assessment may underestimate the chronic risk of profenofos to avian species. This is considered a major data gap in t he risk assessment.Page 11 of 75

 Acute and chronic dietary data are not available for either juvenile (larval) or adult honey bees. Therefore, the risk posed by profenofos residues on pollen and nectar to adult, foraging honey bees is uncertain as is the risk from co ntaminated nectar and pollen brought back to the hive and fed to larval honey bees. Given that profenofos is an insecticide and is very highly toxic on an acute contact basis to bees, oral risk to bees and other beneficial terrestrial invertebrates may be likely where profenofos residues are present in pollen and/or nectar (Non

- Guideline Studies)

. T his is considered a major data gap in the risk assessment.

 Risk to terrestrial plants from spray drift is uncertain as no data are available to assess the

risk of typical end

- use products (TEP) of profenofos on the vegetative vigor of terrestrial plants (OCSPP Guideline 850.4150)

. Profenofos TEP formulations may contain surfactants and adjuvants that increase the absorption and toxicity of the active ingredient to plants. T he test substance used in all available terrestrial plant vegetative vigor studies was technical grade active ingredient (TGAI)

. Given that the available data indicate that profenofos is comparatively less toxic to terrestrial plants than ot her taxa ( e.g. terrestrial invertebrates)

, and would need to be considerably more toxic than the seedling emergence data with TGAI to cause a concern for off

- field terrestrial plants from spray drift, this is considered a minor data gap.Page 12 of 75

2. Problem For mulation

The purpose of problem formulation is to provide the foundation for the environmental fate and ecological risk assessment in support of the Registration Review of the insecticide / miticide profenofos

. The problem formulation sets the objectives for the risk assessment, establishes a risk hypothesis and conceptual model depicting potential risk, and provides a plan for analyzing the data and characterizing the risk associated with the uses of profenofos (USEPA , 2004 ).

2.1. Nature of Regulatory Action

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), all pesticides distributed or sold in the United States must be registered by the United States Environmental Protection Agency (EPA or the Agency). To determine whether a pes ticide can be registered, the EPA

evaluates the product’s 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 (FQPA), and EPA was mandated to impleme nt a new program for the periodic review of pesticides, i.e

., R egistration R eview 1 . 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 t o 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 registration review program, the Agency periodically ree valuates pesticides to make sure that as changes occur, products in the marketplace can be used safely.

Additionally, potential effects to federally listed endangered and threatened species (hereafter

referred to as “listed” ) and their designated critical habitat are also considered under the Endangered Species Act (ESA) in order to ensure that the conti nued registration of profenofos is not likely to jeopardize the continued existence of listed species or adversely modify their critical

habitat. In order to meet the requirements of FIFRA and the ESA, this assessment follows EPA guidance on conducting ecological risk assessments (USEPA, 1998) and the Office of Pesticide Program’s Overview Document, which contains guidance for assessing pesticide risks to n on

listed and listed species (USEPA, 2004).

2.2

. Mode of Action

Profenofos is an insecticide/miticide belonging to the organophosphate class of pesticides. The toxicity of organophosphates 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.

2.3

. Use Characterization

Profenof os is only registered for use on cotton. The only currently registered end

- use product (EPA Reg No. 100

- 669) is an emulsifiable concentrate that is diluted with water or vegetable oil.

1 http://www.epa.gov/oppsrrd1/registration_review/Page 13 of 75

Current use restrictions prohibit application of profenofos within 10 0 feet of any water body and treating crops within 14 days of harvest when diluted with water or 30 days when diluted with oil. The environmental hazards section of the label also adds prohibitions to the application of profenofos in Reeves County, Texas a nd the Dexter National Fish Hatcher y in New Mexico due to the hazard to endangered fish. Profenofos can only be applied by enclosed cab ground application equipment to control cotton bollworm, tobacco budworm, aphids, plant bugs, Lygus bugs , and mites. A erial application is not permitted. The maximum single application rate of profenofos is 0.5 pounds of active ingredient per acre ( lb a.i. /A ) with a minimum application interval of 5 days and a seasonal maximum application rate of 5 lb a.i. /A (maximum o f 10 applications per season ). The use pattern for profenofos is summarized in Table 3 , below.

Table 3 Maximum Application Parameters for Profenofos

Application

Use site Maximum Rate Interval Date Maximum Seasonal

Cotton 0.5 lbs a.i./ A 5 days
( up to 10 applications per

season ) First application date on

emergence in SWCC
(June 1) 5 lbs a.i./ A

A screening level estimate of current usage of profenofos is presented in Table 4

. This screening

level assessment presents usage data on an annual bas is and is derived from USDA’s National Agricultural Statistics Service with data reported from 2004 to 2011

.

Table 4. Profenofos Screening Level Usage Analysis (SLUA) Conducted on August 1, 2013

The Biological and Economic Analysis Division (BEAD) more recently published information on the use of profenofos from 1998

- 2012 (USEPA, 2014). For the most recent periods on record (2007

- 2012), only Arkansas, California, Georgia, Missouri, M ississippi a nd Texas reported use.

Table 5. Profenofos Usage on Cotton in the U.S., Three

- year Averages, 1998

- 2012 1 Percent Crop Treated

No. Crop Lbs. A.I. Average Maxim um 1 Cotton 30,000 <1 <2.5

1998

- 2000 2001

- 2003 2004

- 2006 2007

- 2009 2010

- 2012 2

Total Lbs Applied 447,154 159,067 67,938 19,757 6,767

Total Acr es Treated 696,415 197,499 107,316 25,044 9,454
Proportion of Acres Treated Aerially 50% 17% 24% 34% 0% Percent Crop Treated 1.7% 1.4% 1.1% 0.6% 0.7%Page 14 of 75 1 States reporting use in 1998

- 2006: AL, AZ, AR, CA, FL GA, LA, MS, MO, NC, OK, SC, TN, TX;

States reporting use in 2007

- 2011: AR, GA, MS, MO, TX , CA

2 No usage reported in 2012 Source: Proprietary Usage Data, 1998

- 2012

2. 4

. Conceptual Model

For a pesticide to pose an ecological risk

, it must reach ecological receptors in biologically significant co ncentrations. 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

m u st 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 pr o vides a written description and visual representa tion of the predicted relationsh ips between profenofos, potential routes of exposure, a nd the predicted

effects for t h e assessment endpoint. A conceptual model consists of two major components: risk

h ypothesis and a conceptual diagram (USEPA, 1998).

Based on preliminary estimated environmental concentrations (EECs) and effects data, prelimi nary risk quotients (RQs) were c a lculated for aquatic animals and terrestrial animals and plants. Based on maximum application rates and available fate data for profeno fo s, estimated acute and chronic RQ values are sufficient to exceed levels of concern (L O Cs) for Federally

- listed threatened/endangered (listed) and non

- listed fish and invertebra tes. 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 liste d species of dicot plant s inhabiting semi

- aquatic areas based on exposures of profenofos origin a ting from the maximum application rate. Because of the potential risk from direct effects to the listed and non

- listed taxa described above, lis ted spe cies in all taxa may pote ntially be affected indirectly due to alterations in their habitat and prey items (e.g.,

foods so urces, shelter, and areas to reproduce). These preliminary conclusions are used to deri v e the risk hypothesis and conceptual diagram d iscussed below.

The following risk hypothesis is presumed for this assessment:

Based on the application metho d s, mode of action, fate and transport, and the sensitivity of non

- target aquatic a nd terrestrial species profenofos has the potential to reduce survival, rep r oduction, and/or growth in non

- target terrestrial and aquatic organisms

when us e d in accordance with the current label. These non

- target organisms include federally listed threatened and endangered species as well as non

- listed species.

Conc eptual Diagram

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 e xposed. These transport mechanisms ( i.e ., sources) are depicted in the conceptual models below ( Figures 1 and 2 ) along with the receptors of concern and the potential attribute changes in the receptors due to exposures of profenofos

.Page 15 of 75

1 Figure 1

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

. 3Page 16 of 75

4

5 

### Stressor

Source

Receptors

Attribute Change Profenofos applied to cotton

Direct application Spray drift

Birds / Terrestrial

- phase amphibians / reptiles /

mammals

Juvenile

Adult Terrestrial
insects

Individual organisms

Reduced survival Reduced growth Reduced reproduction Food chain Reduction in prey Habitat integrity Reduction in primary productivity

Reduced cover Community change Terrestrial/riparian plants grasses/forbs, fruit, seeds (trees,

shrubs) Runoff

Mammals 

### Exposure

Media Soil

Ingestion Ingestion

Ingestion Ingestion Dermal uptake/Ingestion Long range atmospheric transport

Root uptake

Wet/dry deposition

Birds / Amphibians Ingestion

Drinking w ater

Figure 2

. Conceptual model for profenofos effects on terrestrial organisms.Page 17 of 75

Analysis Plan

Residues of Concern

The predominant degradate o f profenofos is 4

- bromo

- 2

- chlorophenol. Also formed in equimolar parts with this degradate is O

- ethyl

- S

- propyl phosphorothioate. Additional degradates formed in greater than 10% include 4

- bromo

- 2

- chlorophenyl ethyl ether (BCPEE), 2

- thioethylenecarboxy

4

- h ydroxyphenyl methyl ether (THPME), and cyclohexad i enyl sulfate. The major degradates

, other than O

- ethyl

- S

- propyl phsophorothioate, appear to have limited toxicity compared with the parent profenofos

. Available ecotoxicological information for these degra dates is discussed in the ecological effects characterization in Section 3.2

. P rofenofos, is considered the only residue

of concern for this assessment.

Mixtures

No currently registered profenofos products are co

- formulated other pesticidal active ing redients. Evaluation of pesticide environmental mixtures from tank mixes or due to the presence ( e.g. on foliage) of residues of other pesticides is beyond the scope of this assessment because of a myriad

of factors includi ng identification of other poss ible co

- contaminants and their concentrations, differences in the pattern and duration of exposure among contaminants, and the differential effects of other physical/chemical characteristics of the receiving waters ( e.g. organic matter present in

sediment and suspended water). However, it is acknowledged that not considering mixtures could

over

- or under

- estimate risks depending on the type of interaction and factors discussed above.

Measures of Exposure

EFED uses standard models to evaluate potential exposures to aquatic and terrestrial organisms

as described at http://www.epa.gov/pesticides/science/models_db.htm

.

The most up to date procedures and models are used in th is Registration Review exposure

assessment.

The drinking water exposure pathway for birds and mammals was screened using the Screening Imbibition Program (SIP) screening method. The inhalation exposure pathway was scree n ed using the Screening Tool for Inhalation Risk ( STIR) method. The potential for bioaccumulation of profenofos in aquatic food webs and subsequent risks to mammals and birds via consumption of contaminated aquatic was evaluated using the K
ow - based Aquatic BioAccumulation Model (KABAM ) model. These model s are normally used as screening models during the problem formulation phase of the registration review risk assessment process. However, the problem formulation for profenofos (USEPA, 2008) predates the development (2009

- 2010) of these screening tools.

STIR (STIR v.1.0, November 19, 2010) was used to calculate an upper bound estimate of

inhalation exposure using vapor pressure and molecular weight for vapor phase exposure as well as the maximum application rate and method of application for spray drift. STIR incorporatesPage 18 of 75

results from several toxicity studies including the acute oral and inhalation rat toxicity endpoints (LD 50 of 300 mg/kg

- bw and LC 50 of 3.6 mg/L, respectively) obtained from the “ acute toxicity six

pack” of studies ( which are a series of six guideline studies that are submitted for every registered pesticide product) and the most sensitive acute oral avian toxicity endpoint (mallard LD 50 of 55 mg/kg

- bw) . Based on the results of the STIR model, inhalation exposure alone was not

determined to be a potential pathway of concern for avian/mammalian species on an acute basis. For a sample of the output generated by STIR v1.0, please see Appendix B.

The analysis of the inhalation route in STIR does not consider that aggregation with other

expos ure pathways

- such as dietary, dermal, or drinking water may contribute to a total exposure that has a potential for effects to non

- target animals. However, the Agency does consider the relative importance of alternate routes of exposure in situations wh ere data indicate that other routes may be potentially significant contributors to wildlife risk (USEPA, 2004). The risk description section ( Section 4.2 ), discusses the impact of consideration of other routes of exposure that have been identified as pote ntially important and the degree of certainty associated with screening

- level risk assessment conclusions.

SIP (SIP v.1.0, Released June 15, 2010) was used to calculate an upper bound estimate of exposure using profenofos’ solubility (20 mg/L), the most sensitive acute and chronic avian toxicity endpoints (mallard LD 50 of 55 mg/kg

- bw and northern bobwhite LOAEC of 1 mg/kg

diet, respectively). Drinking water exposure alone was determined to be a potential pathway of concern for mammalian species on a chr onic basis and avian species on both an acute and chronic

basis. For a sample of the output generated by SIP v.1.0, please see Appendix D

.

The KABAM tool ( KABAM v.1.0 , Released April 7, 2009) was used to estimate potential bioaccumulation of hydrophobic organic pesticides in freshwater aquatic ecosystems and risks to mammals and birds consuming organisms which have bioaccumulated these pesticides. Model inputs for KABAM include profenofos’ octanol

- water partition coefficient (log K
ow of 4.83),

sorbtion ( K oc of 3890 ) , the maximum modeled aquatic concentrations (21

- day based on the time to steady state according ot the K
ow ) determined in Section 3.1.2 below

, and the most sensitive acute and chronic avian and mammalian endpoints ( Section 3.2.2 )

.

KABAM ind icates that there is potential for acute dietary

- based risk (RQs range from 0.23

- 0.45 )

and chronic dietary

- based risk (RQs range from 13

- 26 ) for all six of the default modeled avian species consuming fish contaminated by profenofos residues

. This anal ysis likely underestimates chronic risk for avian species consuming contaminated fish residues as it necessitated the use of the LOAEC, since a NOAEC was not acceptable. Additionally, KABAM indicates acute dose

based risk for two (sandpipers and rails) of the six default modeled avian species consuming profenofos contaminated fish (RQs range from 0.03

- 0.47 ) . KABAM did not indicate potential

acute dose

- based risk for mammals consuming fish contaminated with profenofos residues ( RQs range from 0.02

- 0.07 ), but did indicate potential chronic dose

- (RQs range from 10

- 28) and dietary

- based (RQs range from 1.7

- 3.5) risk for all six of the default modeled mammalian species consuming fish contaminated by profenofos residues. For an example of the inputs fo r and output generated by KABAM v.1.0, please see Appendix E

.Page 19 of 75

Measures of Effect

Selected toxicity data are used to calculate risk estimates. Any additional information submitted by the registrant or found in the open literature is also considered. Th e open literature studies are identified using EPA’s ecotox icity (ECOTOX) 2 database , 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 ca n provide insight into the direct and indirect effects of pesticides on biotic communities from loss of species that are sensitive to the chemicals and from changes in structure

and functional characteristics of the affected communities.

Endocrine Disrupt or Screening Program (EDSP)

As required by FIFRA and the Federal Food, Drug, and Cosmetic Act (FFDCA), EPA reviews numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine targe t organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess growth, de velopmental and reproductive effects in different taxonomic groups. As part of the Preliminary Problem Formulation for Registration Review (USEPA, 2008, EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenari os from the existing hazard

database. However, as required by FFDCA section 408(p), Profenofos is subject to the endocrine screening part of the Endocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substa nces (including pesticide active and other ingredients) may have an effect in humans or wildlife similar to an effect produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator may designate.” The EDSP employs a two

- tiered approach to making the statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal

systems. Che micals that go through Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA will determine which, if any, of the Tier 2 tests are necessary based on the avail able data. Tier 2 testing is designed to identify any adverse endocrine

- related effects caused by the substance, and establish

a dose

- response relationship between the dose and the E, A, or T effect.

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between October 2009 and February 2010, EPA issued test orders/data call

- ins for the first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list of chemicals

identified for EDSP s creening was published on June 14, 2013 [1] and includes some pesticides

2 http://cfpub.epa.gov/ecotox/

[1] See http://www.regulations.gov/#!documentDetail;D=EPA

- HQ

- OPPT

- 2009

- 0477

- 0074 for the final second list of

chemicals.Page 20 of 75

scheduled for registration review and chemicals found in water

. Neither of these lists should be construed as a list of known or likely endocrine disruptors. Profenofos is not on List 1. For further information on the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the test guidelines and Tier 1 screening battery, please visit our website [2]

.

2 .5 Previous Assessments

The most recent major risk assessment on profenofos was for the Reregistration Eligibility Decision (USEPA, 1999). The assessment noted significant data gaps regarding the persistence of profenofos under the acidic soil and water conditions that characterize its major use areas.

H owever, additional fate data were not requested because fish kill incident reports were taken to provide evidence that profenofos will persist for sufficient time at concentrations that result in fish mortality within the use area.

For aquatic organisms , t he risk assessment predicted acute risk to listed freshwater fish species

and listed and non

- listed saltwater fish species, as well as acute and chronic risk to both listed

and non

- listed species of freshwater and saltwater invertebrates. However, chro nic risk was not predicted for fish.

For terrestrial organisms, the risk assessment predicted acute risk to listed avian species feeding on all dietary items and non

- listed avian species feeding on all dietary items except for

seeds/fruit. Chronic risk was predicted for avian species feeding on all dietary items. For small and medium mammals, risk was predicted for listed and non

- listed species feeding on short grass and listed species only consuming forage and small insects. For large mammals, only l isted species consuming short grass were considered at risk.

Listed and non

- listed terrestrial plants were expected to be at risk from channel runoff only.

In 1989, the U.S. Fish and Wildlife Service issued a biological opinion for 109 pes ticides,

in cluding profenofos (USFWS, 1989). USFWS concluded jeapordy for 21 aquatic species. This opinion predates the new approach for national

- level pesticide Endangered Species Act assessmentmnets based on the National Academy of Sciences (NAS) report (National Research Council, 2013)

.

3. Analysis

3.1. Exposure Characterization

3.1.1. Environmental Fate and Transport Characterization

The major route of dissipation of profenofos in the environment is by microbial metabolism as well as by the abiotic proce ss of hydrolysis. Profenofos is fairly non

- persistent, with aerobic and

[2] Availab le: http://www.epa.gov/endo/Page 21 of 75

anaerobic soil metabolism half

- lives of 2.3 and 2.1 days respectively. Degradation due to hydrolysis varies with pH, with half

- lives ranging from 107

- 475 days for acidic (pH 5) wat ers, 24.4

- 69.9 days for waters with neutral pH (pH 7), and 0.32

- 0.43 days for alkaline waters (pH 9)

. Profenofos has a slight mobility potential to leach in soils. The organic carbon partition coefficient (K OC ) was determined to be 3890.

The pred ominant degradate of profenofos is 4

- bromo

- 2

- chlorophenol. Also formed in equimolar parts with this degradate is O

- ethyl

- S

- propyl phosphorothioate. Additional degradates formed in

excess of 10% include 4

- bromo

- 2

- chlorophenyl ethyl ether (BCPEE), 2

- thioet hylenecarboxy

- 4

- hydroxyphenyl methyl ether (THPME), and cyclohexadenyl sulfate. The major degradates , other

than O

- ethyl

- S

- propyl phosphorothioate, appear to have limited toxicity compared with the parent profenofos. O

- ethyl

- S

- propyl phosphorothioate was not tracked in any submitted studies; therefore, its rate of formation and decline are unknown . However, one hydrolysis study (MRID 41939001) suggests that O

- ethyl

- S

- propyl phosphorothioate further degrades into O

- ethyl phosphate and 1

- propanethiol.

S urface Water Impact

Profenofos breaks down rapidly under aerobic and anaerobic conditions and dissipates in neutral

to alkaline soils with a half

- life of several days. Acidic conditions typical of the areas where most profenofos use occurs favor a slower breakdown. Although not highly mobile, profenofos may reach surface waters through spray drift or runoff.

Surface water advisory included on current product label :

“ This pesticide is acutely toxic to fish and wildlife. Use with care when applying to area s frequented by wildlife or adjacent to any body of water. Due to the hazard to endangered fish, the application of this product is prohibited in Reeves County, TX and within one mile of the Dexter National Fish Hatchery in NM. For terrestrial uses, do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark. Do not contaminate water by cleaning of equipment or disposing of equipment wash water. Because of the potential for surface water runoff from treated areas and the possibility of fish kills, do not apply to saturated soil, and do not treat while precipitation is occurring or while conditions favor runoff from the

treated area. ”

T able 6 lists the environmental fate properties of prof enofos in the submitted environmental fate and transport studies

.

Table 6

. Summary of P rofenofos Environmental Fate Properties

Study Value (units) MRID # Study Status

Vapor Pressure 3.46E

- 06 torr 41905001 Supplemental

Octanol

- water Partition

Coefficien t (log K OW ) 4.83 @ 25 °C 42854201 AcceptablePage 22 of 75 Study Value (units) MRID # Study Status

Hydrolysis T 1⁄2 (at 25  C) 1 107

– 475 @ pH 5

24.4

– 69.9 @ pH 7

0.32

- 0.43 @ pH 9 41627309,

41939001 Acceptable,

Acceptable

Aquatic Photolysis T 1⁄2 1 266 Days 41939002 Acceptable

Aerobic Soil Metabolism T 1⁄2 1 2.3 da ys @ 25 °C 42334302 Acceptable

Anaerobic Soil Metabolism

T 1⁄2 1 2.1 days @ 25 °C 42334303 Acceptable

Anaerobic Aquatic Metabolism, T 1⁄2 1 3.8 days @ 25 °C 42218101 Acceptable

Sorption Koc 3890 (mL/g) 48612101 Supplemental

Fish Bioconcentration Factor (BCF) 2 9x (body) 45x (head) 682x (viscera) 92148059 Supplemental

1 Half

- lives were recalculated using PestDF (EFED, 2014)

3.1.2. Measures of Aquatic Exposure

Aquatic exposures are quantitatively estimated for the only use site, co tton, with modeling scenarios that represent high potential exposures for profenofos use.

Profenofos environmental fate data used for generating model parameters are listed in Table 7

. Chemical property input values were chosen in accordance with curren t input parameter guidance (USEPA, 2009)

.Page 23 of 75

Table 7. Summary of environmental fate parameters for profenofos and values used for
modeling (SWCC).

Parameter Range Value Used in Model Source

Molecular Weight 373.63 (g/mol) 373.63 (g/mol) Product chemistry

Solubility in water 20 mg/L 20 mg/L IRED (USEPA 2000)

Vapor Pressure 9.30 x 10

- 7 torr 9.30 x 10

- 7 torr The Pesticide Manual

, 1997, p. 1006

Hydrolysis T 1⁄2 (at 25  C) 1 107

– 475 (pH 5)

24.4

– 69.9 (pH 7)

0.32

- 0.43 (pH 9) 69.9 days MRID 41627309,

419390 01

Aquatic Photolysis T 1⁄2 1 T 1⁄2 = 266 days 266 days MRID 41939002

Aerobic Soil Metabolism

T 1⁄2 1 2.3 days @ 25 °C 6.9 days 2.3 days x 3 MRID 42334302

(EFED, 2009)

Anaerobic Soil

Metabolism T 1⁄2 1 2.1 days @ 25 °C MRID 42334303

Water Column

Metabolism T 1/2 1 13.8 days @ 25 °C

6.9 days x 2 (EFED, 2009)

Anaerobic Aquatic Metabolism, T 1⁄2 1 3.8 days @ 25 °C 3.8 days @ 25 °C MRID 42218101

Sorption Koc 3890 (mL/g) 3890 (mL/g) MRID 48612101
Application Efficien cy 0.99 ground spray (EFED, 2009)

Foliar Half

- Life 35 days (EFED, 2009)

Spray Drift % 0.0042 AgDrift (v 2.1.1)

with a 100 ft buffer

Henry’s Law Constant 2.38 x 10

- 7 atm

- m 3

mol

- 1 2.38 x 10

- 7 atm

- m 3

mol

- 1 (EFED, 2008)

1 Half

- lives were recalculated using PestDF (EFED, 2014)

Results from the Surface Water Concentration Calculator ( SWCC v1.1) model evaluating all

available cotton scenarios a re presented in Table 8

. Each scenario was designed to represent a general geographical area. Maximum peak EECs were found in the Texas

- cotton scenario, while

the Miss issippi

- c otton scenario produced the maximum chronic concentrations . Maximum benthic po re water EECs were also calculated by the MS

- cotton scenario with peak concentrations of 1.22 ppb and 21

- day concentrations of 0.753 ppb ( Table 9 )

.

Table 8

. Tier II Concentrations of Profenofos in Surface W ater

. Estimated Environmental Concentrations (EEC ) of profenofos residues for cotton in the

EPA Pond with the SWCC model.

The simulations used the maximum labeled number (10) of applications and application rate (0.5 lb. a.i./A/application), and a maximum seasonal application rate (5 lb. a.i./A).

1

- in

- 10 year Profenofos Concentration (μg/L)Page 24 of 75

Scenario

- State Crop Peak 21

- Day Average 60

- Day Average

CA

– Cotton 1.64 1.12 0.764

MS

– Cotton 10.3 5.05 2.75

NC

– Cotton 9.48 4.36 2.59

TX

– Cotton 10.9 4.76 2.39

Table 9. Tier II Concentrations o f Profenofos in Benthic Pore Water

Estimated Environmental Concentrations (EEC) of profenofos residues

for cotton in Sediment Interstitial Water ( Pore Water ) with the SWCC

model.

The simulations used the maximum labeled number (10) of applications and ap plication rate (0.5 lb. a.i./A/application), and a maximum seasonal application rate (5 lb. a.i./A).

1

- in

- 10 year Profenofos Concentration (μg/L)

Scenario

- State Crop Peak 21

- Day Average

NC

– Cotton 1.22 0.753

TX

– Cotton 0.95 0.66

Monitoring Data

Monitoring data for profenofos was downloaded from the Water Quality Portal database ( http://water qualitydata.us/ ) on June 4 , 2015. The Water Quality Portal integrates data from the USGS National Water Information System (NWIS), EPA’s STORET data warehouse, and USDA ARS STEWARDS platform. A total of 2,336 records were retrieved for the analysis of

pr ofenofos. The data covered a time period from 1993 to March 2015. Twenty eight states were represented in the data set including (states that are bold represent current cotton growing states) : AZ

, CA

, AL

, AR , CO, CT, FL

, GA , HI, IN, KY, MA, MD, MI, MN, MO

, NC , NE, NV, NY, OH, OR, PA, TX , VA, WA, and WI. All of the samples were non

- detects.

Data from California Department of Pesticide Regulation was also accessed for this assessment on June 8, 2015 . The sampling period for which profeno fos was monitored in surface and ground water was 2002

- 2005 and 2007

- 2009. A total of 735 records were retrieved, all of

which were non

- detects with a limit of quantitation of 0.05 ppb. The CADPR surface water

database can be found at: http://www.cdpr.ca.gov/docs/emon /surfwtr/surfcont.htm

.

Groundwater monitoring d ata provided by the Texas Commi s sion of Environmental Quality (TCEQ) to the EPA returned 245 results. A total of 245 result s were retrieved and occurred in

the y ears 1987, 1988, 1990, and 2003. All of the r esults were non

- detects with a limit of quantitation of 0.0059 ppb.

None of the data listed above is a result of sampling targeted to profenofos use . T hat coupled

with a less robust sample frequency would suggest that the monitoring results are probably missing the peak concentrations of profenofos

.Page 25 of 75

3.1.3. Measures of Terrestrial Exposure

3.1.3.1. Terrestrial Animals

Ingestion of Food Items Based on Foliar Application

Exposure estimates for terrestri al animals assumed to be in the target area or in an area exposed to spray drift are derived using the T

- REX 3 (Terrestrial Residue EXposure model) model (version

1.5.2

., 6/11/2013 ). This model incorporates the Kenaga 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 an approximation of the highest residue value observed in the data set (Hoerger and Kenaga 1972). Consideration is given to differ ent types of feeding strategies for

mammals and birds ; including herbivores, insectivores and granivores. For dose

- based exposures, three weight classes of birds (20, 100, and 1000 g) and mammals (15, 35

, and 1000 g) are considered. Two studies are availa ble with dislodgeable foliar residue data for profenofos (MRIDs 42815303 and 42851304) indicating foliar dissipation half

- lives of less than one day. However, EFED requires three foliar dissipation half lives in order to use this data quantitatively in th e risk assessment. Therefore, the default foliar dissipation half

- life of 35 days is used based on the work

of Willis and McDowell (1987) for risk estimation. The impact of the potentially shorter foliar dissipation half

- lives derived from empirical data will be characterized in the risk description

section. Th is assessment assumes a maximum single application rate of 0.5 lbs a.i./A with 10 application s of profenofos per year (5 day minimum reapplication interval) to estimate terrestrial exposure for thi s assessment. The dietary

- based EECs (upper bound Kenaga) on a variety of food

items from the use of profenofos applied at the maximum label rate is provided in Table 10 ; dose

based EECs are provided in Table 1 1

.

Table 10 . T

- REX Calculated Dietary

- Bas ed EECs of Profenofo s on Food Residues.

Food Type Cotton Use Site Maximum Dietary

- based EECs (mg/kg)

Short Grass 800

Tall Grass 367
Broadleaf plants 450
Fruits/pods/ seeds 50
Arthropods 313

3 USEPA. 2013. Pesticides: Science and Policy. Terrestrial Models, T

- REX Version 1.5.2 http://www.epa.gov/oppefed1/model s/terrestrial/Page 26 of 75

Table 1 1 . T

- REX Calculated Maximum Dose

- Based EECs of Prof enofos Use on Terrestrial

Food Residues ( Cotton Use Site)

Food Type Dose

- based EECs (mg/kg

- bw) (birds) Dose

- based EECs (mg/kg

- bw) (mammals)

Small (20 g) Medium

(100 g) Large

(1000 g) Small

(15 g) Medium

(35 g) Large

(1000 g) Short grass 911 520 233 763 527 122 Tall grass 418 238 107 350 242 56.0 Broadleaf plants 513 292 131 429 297 68.8 Fruits/pod s 56.9 32.5 14.5 47.7 33.0 7.64 Arthropods 357 203 91.1 299 206 47.9 Seeds (granivore) 12.7 7.22 3.23 10.6 7.32 1.70

3.1.3.2. Terrestrial Plants

Profeno fos exposure to terrestrial and semi

- aquatic plants i s estimated using the TerrPlant 4
( v ersion 1.2. 2 ) model. The model generates EECs for plants residing near a use area that may be exposed via runoff and/or spray drift. The EECs are generated from one ap plication at the maximum rate for a particular use and compound

- specific solubility information. Only a single application is considered because it is assumed that for plants, toxic effects are likely to manifest shortly after the initial exposure and tha t subsequent exposures do not contribute to the response. Hence, the model estimates EECs based on application rate, the solubility factor

, and default assumptions of drift. The EECs for terrestrial and semi

- aquatic plants for a single application of

p rof enofos at the maximum label rate are presented in Table 1 2

.

Table 1 2

. Max EECs for Terrestrial and Semi

- Aquatic Plants Near Profenofos Use Areas.

Single Max. Application Rate (lbs a.i./A

, Cotton Use

Site ) EECs (lbs a.i./A)

Total Loading to Adjacent Dry Areas (sheet runoff + drift) Total Loading to Semi

Aquatic Areas (channelized runoff + drift) Drift EEC

0.5 0.0105 0.105 0.005

3.2. Ecological Effects Characterization

The ecological effects characterization for profenofos is based on da ta generated from guideline studies submitted by the registrant and from open literature studies in the ECOTOX database (http:/www/epa.gov/ecotox).

A brief description of available aquatic and terrestrial toxicity data used to calculate RQs is provided below in Sections 3.2.1 and 3.2.2

. Section 3.2.3 describes the available reports of ecological incidents involving the use of profenofos

.

4 USEPA. 2013a. Pesticides: Science and Policy. Terrestrial Models, TerrPlant Version 1.2.2. http://www.epa.gov/oppefed1/models/terrestrial/Page 27 of 75

Some open literature data is available that indicates that chiral isomers of profenofos can have

differential toxici ty. For example, Leader and Casida (1982) found that the (

- ) isomer was 4

- 23 times more toxic to mice and several insect species than the (+) isomer. However, n one of the acceptable registrant

- submitted or open literature data identify the proportion of each isomer utilized in the ecotoxicity studies. Therefore, there is potential for th is assessment to over

- or under

- estimate risk to non

- target organisms depending on the production and fate of profenofos

isomers in the environment and the actual rati o of isomers used in the ecotoxicity studies.

3.2.1. Aquatic Effects Characterization

The most sensitive a quatic toxicity data for animals and plants are summarized in Table 1 3

. For

freshwater and estuarine/marine fish and invertebrates (and for aqua tic

- phase amphibians, for which fish are considered surrogates)

, the compound is considered very highly toxic

. Many of the aquatic studies conducted using profenofos may have underestimated the actual toxicity of the compound since they did not analytical ly measure concentrations

, and the endpoints are reported using nominal concentrations. Many of these were older studies conducted in static conditions

and often in somewhat alkaline water (>8.0 pH) where profenofos is most likely to degrade quickly. The refore, the reported nominal concentrations may represent an overestimate of actual profenofos exposure and the effects endpoints would therefore be more sensitive than reported.

Fish The most sensitive acute endpoint for freshwater fish that may be used quantitatively was the 96

- h our LC 50 for bluegill ( Lepomis machrochirus ) of 14.1 μg/L from Mayer and Ellersieck ( 1986

, MRID 400980

- 01). Although this study used nominal concentrations, pH was maintained at 7.1 in the study ; therefore

, actual concentration s may not differ significantly from the nominal levels. In the open literature, a more sensitive acute freshwater fish study ( Pandey et al., 2011, E COTOX reference number E158179) using spotted snakehead ( Channa punctatus ) determined an LD 50 of

2.31 μg/L after exposure to the profenofos formulation CELCRON ( 50% a.i. in an emulsifiable

concentrate formulation that is not currently registered in the U.S.)

. EFED has reviewed this study and under the current guideline standards considered the study to be supp lemental (due to lack of measured residues and pooling of study data collected from different times) . T he endpoint may be used qualitatively in risk assessment. The most sensitive acute endpoint for estuarine/marine

fish was the 96

- hr LC 50 for pinfish ( L agodon rhomboides ) of 7.7 μg/L (MRID 000859

- 60)

. Although this study used nominal concentrations, pH at 0 hours was 8.0 but decreased to 7.5

- 7.6 by test termination ; therefore

, actual concentrations may not differ significantly from the nominal

levels.

Although chronic study data are not available for the most sensitive freshwater and estuarine/marine species, an early life stage test using fathead minnow ( Pimephales promelas;

MRID 000859

- 58) determined a 31

- day NOAEC of 2.0 μg a.i. /L based on 31% red uced survival

and 10% reduced total length of juveniles at 4.4 μg a.i. /L compared to control fish . Using the

available acute fathead minnow endpoint of 122 μg a.i. /L (MRID 492906

- 01 ) and the chronic fathead minnow endpoint, an acute

- to

- chronic ratio (ACR) of 61 was generated and applied to the most sensitive acute freshwater and saltwater fish endpoints to result in conservative estimates of

0.23 μg a.i. /L and 0.13 μg/L chronic endpoints for bluegill and pinfish, respectively.Page 28 of 75

Aquatic Invertebrates

The most sensitive acute endpoint for freshwater invertebrates that may be used quantitatively was

the 48

- hour LC 50 for Daphnia magna of 0.91 μg/L (MRID 00108015). Although this study used nominal concentrations, pH remained below 7.50 ; t herefore

, actual conc entrations may not differ significantly from the nominal levels. The most sensitive acute endpoint for estuarine/marine

invertebrates was 2.4 μg/L ( 96

- hr LD 50 for the mysid, Americamysis bahia

, MRID 00085963 ). The chronic daphnid NOAEC is 0.20 μg/L based on visual inspection of figures in the study report

on ~ 70% increased mortality and ~75% reduced offspring production at 0.33 μg/L . The chronic mysid NOAEC is 0.22 μg/L based on 45% increased mortality and 76% reduced offspring production at 0.35 μg/L

. I n the open literature, a much more sensitive acute LC 50 endpoint for

freshwater invertebrates of 0.041 μg/L for Ceriodaphnia dubia, based on nominal concentrations, was reported from Woods et al ., 2002 (Ecotox reference number E 158195 ) using TGAI . EFED

ha s reviewed this study and

, under the current guideline standards

, considered the study to be supplemental

, and the endpoint may be used qualitatively in risk assessment. The potential impact of the more sensitive open literature data on the risk assessmen t is discussed below in Section

4.2.1 The pH in this study was slightly basic (8.0 ± 0.1) and given profenofos’ degradation potential under basic conditions, it is possible that actual exposure concentrations in this study may

be less than the nominal conc entrations. No ecotoxicological data is available for benthic aquatic

invertebrates.

Aquatic Plants

For a quatic vascular plants, the IC 50 for duckweed ( Lemna gibba ) was 3,460 μg a.i. /L (time

weighted average concentration) based on decreased frond numbe r. At the duckweed NOAEC of 1,270 μg a.i. /L , there was an approximately 13% inhibition o f frond number. No quantitative data is available for aquatic non

- vascular plants. A non

- vascular plant study with the green algae ( Pseudokirchneriella subcapita ta

, MRID 48612104) was considered supplemental because the

time duration was only 72 hours under regular lighting conditions ( i.e. 4

- 5 klux) with low replication (3 replicates) and narrowly did not meet several of the control performance criteria ( i.e.. growth and vari ability criteria for control plants ) established by EPA guidelines for aquatic nonvascular plant testing (OCSPP 850.4500 guideline)

. T he 72

- hour IC 50 and NOAEC endpoints

of 508 μg a.i. /L and 130 μg a.i. /L , respectively, from this study may only b e used qualitatively in risk assessment. As control algae did not meet the established performance criteria and the study was not conducted for the guideline requirement of 96

- hours, the estimated endpoints may somewhat underestimate actual toxicity to gr een algae. No other aquatic

, non

- vascular plant data is available for profenofos and this is considered a data gap , but this study indicates that non

vascular plants may be more sensitive than vascular aquatic plants.

Profenofos Degradates For the degra date, 4

- bromo

- 2

- chlorophenol, the only ecotoxicological data was for a marine green algae, Tetraselmis marina (Liu and Zhang, 2014) w hich was reported to have an EC 50 of 120 μM (equivalent to 24,900 μg/L). No empirical aquatic ecotoxicological data is ava ilable for the degradate, O

- ethyl

- S

- propyl phosphorothioate which is pre dicted to form on an equimolar basis

with the 4

- bromo

- 2

- chlorophenol degradate , or any of the other degradates.Page 29 of 75

EFED attempted to see if QSAR could be used to estimate the toxicity of profenofos degradates ( Appendix F )

. This analysis found that QSAR models performed well

, or reasonably well

, in predicting the toxicity of parent profenofos to algae, acute toxicity to daphnia, chronic toxicity to freshwater fish, acute and chronic tox icity to mysids ; h owever, it did not perform well when predicting the chronic toxicity of profenofos to daphnids, acute toxicity to freshwater fish, or acute and chronic toxicity to saltwater fish. For those taxa where the model performed well predicting

t he toxicity of parent profenofos, the only degradates for which the predicted toxicity approached the predicted toxicity of parent profenofos was the O

- ethyl

- S

- propyl phosphorothioate degradate

. This degradate was predicted to be approximately 3x less tox ic to algae, 1.6x less toxic to daphnids on an acute basis, of identical toxicity to freshwater fish on a chronic basis, 1.5x less toxic to mysids on an acute basis

, and 1.6x less toxic to mysids on a chronic basis

. T he O

- ethyl phosphate

metabolite from O

- ethyl

- S

- propyl phosphorothioate which was predicted to be 2.5x less toxic to freshwater fish on a chronic basis than its parent compound(s). This degradate may be metabolically produced as a detoxifying mechanism by CytP450 in animals and therefore the

e xisting toxicity studies may potentially already account for its toxicity (despite not tracking its formation in those studies). All additional degradates were predicted to be of low toxicity compared to parent profenofos.

Table 1 3

. Summary of the Acute and Chronic Toxicity Data used for Risk Estimation for Aquatic A nimals Exposed to Profenofos

. Bolded values represent the endpoints used for

risk estimation.

Species Test

substance (% a.i.) Acute Toxicity Chronic Toxicity

96

- hr

LC 50 /EC 50 (μg a.i./L) 48

- hr EC 50

(μg a.i./L) Toxicity

Classification (MRID, study classification) NOAEC/

LOAEC (μg a.i./L) Endpoints

(MRID, study classification)

Bluegill sunfish ( Lepomis macrochirus ) TGAI

90.6 % 14.1

(n ominal) -- Very Highly

Toxic (4009 80 01

, Supplemental ) 0.23 ACR

Calculation 1

Fathead minnow ( Pimephales promelas ) TGAI

93.2% 122

( m ean

measured) - - Highly Toxic ( 492906 01, Acceptable ) 2.0 /4.4

(31

- D ay endpoint

,

mean

measured ) Mortality, Total

Length (000859 58

, Acceptable)

Waterflea ( Daphnia magna ) TGAI

90.4 % a. i. -- 0 .91 (nominal) Very Highly

Toxic ( 00108015

, Acceptable) (42

- days)

0.2/0.33 (mean

measured) Mortality,

Reduced Reproduction ( 000859 64 Acceptable)

Pinfish ( Lagodon rhomboids ) TG A I

90.6% 7.7

(n ominal) -- Very Highly

Toxic ( 000859 60, Acceptable ) 0.13 AC R

Calculation 2

Mysid shrimp ( Americamysis bahia ) TGAI

9 0.6% 2.4

(mean

measured) -- Very Highly

Toxic ( 00085963, Supplemental ) (28

- days)

0.22 /0.35 (mean

measured) Mortality

,

Reduced Reproduction (000859 63

, Acceptable) Aquatic PlantsPage 30 of 75

Species Test

substance (% a.i.) Acute Toxicity Chronic Toxicity

96

- hr

LC 50 /EC 50 (μg a.i./L) 48

- hr EC 50

(μg a.i./L) Toxicity

Classification (MRID, study classification) NOAEC/

LOAEC (μg a.i./L) Endpoints

(MRID, study classification)

Duckweed ( Lemna gibba ) TGAI

93.2 % a.i. N / A N / A N / A 7

- day I C 50

= 3,460

7

- d NOAEC/

LOAEC = 1,270 / 2,450 (TWA) Frond numbers

( 48612103

, Acceptable)

Non

- vascular aquatic plants N/A N / A N / A N / A No Data No Data

1 Since the acute bluegill LD 50 is more sensitive than the acute fath ead minnow endpoint and chronic data is only available for the fathead minnow, an acute

- to

- chronic ratio (ACR) was generated from the acute and chronic fathead minnow endpoints and applied to the bluegill LD 50 to conservatively evaluate chronic effects to the most

sensitive freshwater fish.

2 No data is available for chronic effects of profenofos to estuarine/marine fish. An ACR was generated from the acute and chronic fathead minnow endpoints and applied to the pinfish LD 50 to evaluate chronic effects t o estuarine/marine fish.

3.2.2. Terrestrial Effects Characterization

Toxicity values for terrestrial animals and plants are summarized in Tables 1 4 and 1 5

, respectively

. Profenofos is classified as moderately toxic to mammals on an acute oral basis,

mo derately to highly toxic to birds on a n acute oral basis and highly toxic to birds on a su bacute dietary exposure basis.

Birds In an acute oral study with the canary ( Serinus canaria ), several canaries regurgitated profenofos

administered in the diet at 20 mg a.i./kg bw (one of which subsequently died). Since the dose these birds actually received is uncertain, the risk assessment will use the regurgitation

- based NOAEC of 10 mg a.i./kg bw as a conservative surrogate for the acute endpoint used in risk e stimation. Regurgitation was only observed at the nominal 20 mg a.i./kg bw dose and therefore did not appear

to follow a dose

- response relationship

. Thus, there is some uncertainty as to whether this was a

toxic effect of the test substance. Removal of this treatment group resulted in an estimated LD 50 of 40.8 mg a.i./kg bw with 95% confidence intervals of 18.3 to 57.4 mg ai/kg bw. This estimated

LD 50 will be used qualitatively to characterize acute risk to avian species. On a chronic basis, profenofo s resulted in reproductive impairment ( i.e. reduction in egg production/viability of eggs) to bobwhite quail at all doses tested resulting in a LOAEC of 1 ppm (maximum effect at this

concentration of 33% inhibition on the number of normal hatchlings per eg gs laid) . The lack of a valid NOAEC for avian reproduction is considered a major data gap.

Mammals

In chronic two

- generation mammalian reproduction studies (MRIDs 43213308 and 43213309)

, profenofos was incorporated continuously in the feed of male and female Sprague

- Dawley rats for two successive generations at dietary concentrations of 0, 5, 100 and 400 ppm. The NOAE C was 100 ppm (7.3 mg/kg

- diet/day), based on reduced body weights and food consumption of F 0 and F 1Page 31 of 75

males and females, and decreased pup body weight of both sexes in F 1 and F 2 litters at 400 ppm (29 mg/kg

- diet/day). The maximum percent inhibition at the LOAEC for each of these endpoints was approximately 10

- 15% relative to controls.

Terrestrial Plants Concerning profenofos’ effects to t errestrial plants, p reviously, MRID 41627305 had been considered acceptable and used to provide data on vegetative vigor to support the registration of profenofos. This study found no effects on any of the ten species tested up to the maximum rate

tested of 1.0 lb a.i./A. However, t he study was conducted with TGAI profenofos (90.4% purity) in place of a typical end

- use product (TEP). Therefore, it has been downgraded to supplemental

, may only be used qualitatively in the risk assessment

, and is considere d a data gap

. Similarly, the previously acceptable seedling emergence study (MRID 41627307) has been downgraded to supplemental based on the use of TGAI instead of TEP. However, since surfactants and other inert ingredients in TEP s are likely to disassoci ate from the test substance before reaching the plant life stage tested in this study, this study may be used quantitatively in the risk assessment. The most sensitive species in the seedling emergence study was cucumber with a NOAEC and EC 25 of 0.11

and 0.13 lb a.i./A , respectively. None of the monocots showed any effects after treatment with up

to 1. 0 lb a.i./A.

Table 14

. Profenofos Terrestrial Animal Toxicity Summary . Bolded values indicate endpoints used in risk estimation.

Parameter Study Type Spec ies Exposure

Duration Test

substance (% a.i.) Toxicity Value /

Endpoint Affected Reference Toxicity

Classification

/ Study

Classification

1. Abundance ( i.e ., survival, reproduction, and growth) of

individual

birds 1a. Acute

(Dose

- based) Mallard du ck

Anas platyrhyncho

s Single oral

dose TGAI

( 89.4% ) 55.0 mg/kg bw

(LD 50 ) / Mortality 41627301

Moderately

Toxic/ Acceptable

Canary

Serinus

canaria Single oral

dose TGAI

( 93.2 % ) 10 mg/kg bw

(NOAEC ) / Regurgitation 4 8612102

Highly Toxic / Supplemental (Quant itative)

1b. Acute (Dietary

based) Northern

Bobwhite

Colinus virginianus 8

- Day dietary TGAI ( 92 % ) 57 mg/kg diet

(LC 50 ) / Mortality 43107301

Highly Toxic / Acceptable

1c. Chronic (Dietary

based) Northern

bobwhite ( C. virginianus ) Avian

reproduction

stu dy TGAI

( 90.6% ) < 1 mg/kg

- diet

(NOAEC)/ Reproductive impairment 00086661

Acceptable

2. Abundance ( i.e ., survival, reproduction, and growth) of 2a. Acute

- oral Mouse ( Mus

musculus ) Single oral

dose TGAI

( %ai not reported ) 298 mg/kg bw

(L D 50 ) 00105226

Moderately

toxic / AcceptablePage 32 of 75

Parameter Study Type Spec ies Exposure

Duration Test

substance (% a.i.) Toxicity Value /

Endpoint Affected Reference Toxicity

Classification

/ Study

Classification

individual

mammal Ra bbi t ( Oryctolagus

cuniculus ) Single oral

dose TGAI

( %ai not reported ) 300 mg/kg bw

(LD 50 ) 00105228

2b. Acute

inhalation Rat ( Rattus

norvegicus ) 4

- hour

inhalation

exposure TGAI

( %ai not reported ) 3. 3 6 mg/L (LC 50 ) 001 0 9428

2c . Chronic Rat ( Rattus

n orvegicus ) 2

- Generation

reproduction study TGAI

( 92 % ) 7.3

(NO EL)

LO EL =

29 mg/kg

- diet

based on decreased

F0 and F1 body weight s, food consumption and decreased pup body weight F1 and F2 43213308

43213309 Acceptabl e

3. Survival of

beneficial

insects 3a. Acute

Contact (Adult)

Honey Bee

( Apis mellifera ) 48 hours TGAI ( 90.4% ) 0.0953 μg a.i./bee

(LD 50 )/ Mortality 41627308

Highly Toxic Acceptable

3b. Acute Oral (Adult) 48 hours N/A No Data No Data

3c. Chronic

Or al (Adult) 10 days N/A No Data No Data

3d. Acute Oral (Larvae) 8 Days N/A No Data No Data

3e. Chronic Oral (Larvae) 21 Days N/A No Data No Data

Table 15 . Summary of Tier I I Terrestrial Plant Toxicity Data for Profenofos

Crop Species EC 25 (lbs

a. i./A) NOAEC (lbs

a.i./A) Most

sensitive
parameter MRID

Seedling Emergence

Monocots Oat >1.0 1.0 N/A 41627307

Ryegrass >1.0 1.0 N/A 41627307

Corn >1.0 1.0 N/A 41627307

Onion >1.0 1.0 N/A 41627307

Dicots Lettuce >1.0 0.333 Dry Weight 41627307

Soyb ean >1.0 1.0 N/A 41627307

Carrot >1.0 1.0 N/A 41627307

Tomato >1.0 1.0 N/A 41627307Page 33 of 75

Crop Species EC 25 (lbs

a. i./A) NOAEC (lbs

a.i./A) Most

sensitive
parameter MRID

Cucumber 0.130 0.111 Dry Weight 41627307

Cabbage >1.0 0.333 Plant Height, Dry Weight 41627307

Vegetative Vigor

Monocots Oat No Data No Data N/A N/A

Ryegrass No Data No Data N/A N/A

Corn No Data No Data N/A N/A

Onion No Data No Data N/A N/A

Dicots Soybean No Data No Data N/A N/A

Carrot No Data No Data N/A N/A

Tomato No Data No Data N/A N/A

Cucumber No Data No Data N/A N/A Cabbage No Data No Data N/A N/A

Lettuce No Data No Data N/A N/A

3.2.3. Review of Incident Data

A review of the Environmental Incident Information System (EIIS , version 2.1 .1 ) database and the Incident Data System (IDS) database , which are maintained by the Agency’s Office of

P esticide Programs ; and the Avian Monitoring Information System (AIMS), which is maintained by the American Bird Conservancy, for ecological incidents involving profenofos was completed

on April 7, 201 5

. The review specified a total of 23 reported ecologic al incidents associated with the use of profenofos which are summarized in Table 1 6

.

This total excludes incidents classified as ‘unlikely’ or ‘unrelated’ and only includes those incidents with certainty categories 5 of : ‘possible

, ’ ‘probable

, ’ and ‘high ly probable’ (for EIIS) ; and ‘possible

, ’ ‘ probable

, ’ ‘likely

, ’ ‘highly likely

, ’ and ‘certain’ (for AIMS). Incidents classified as ‘unlikely’ the result of

, or ‘unrelated’ to

, profenofos will not be included in this ecological risk

assessment conducted for Registration Review.

All of the profenofos incidents, excluding those classified as ‘unlikely’ or ‘unrelated

, ’ occurred between 1992 and 1999 in Alabama, Georgia, Louisiana and Mississippi. Twenty

- two of the profenofos in cidents involved fish and one in cident involved crayfish . The certainty categories regarding the likelihood that the use of profenofos caused the 23 incidents ranged from ‘possible’ (7 incidents) to ‘highly probable’ (6 incidents). Ten of the incidents were considered registered

5 The Ecological Incident Infor mation System (EIIS) used by EPA to store incident data relies on the following certainty indices:

 Highly Probabl e : (residues detected in affected organisms and other lines of evidence support cause)

 Probable : (residues were not measured or the measured r esidues were not sufficient to be considered toxic, but pesticide was used in close proximity and would be capable of exerting such an effect)

 Possible : multiple pesticides were used in close proximity and any of them are capable of causing such an effect

.

 Unlikely: there are no measured residues and the observed effects are not consistent with those caused by pesticides

use d in the area or there was no pesticide use known in the area.

 Unrelated: effects observed in the incident are unrelated to pesticid e use.Page 34 of 75

uses a t the time of the incident, 2 involved misuses, and the legality of use was undetermined in

11 incidents. Ten of the incidents involved additional chemicals besides profenofos ; however

, in 4 of those incidents, profenofos was the only pesticide for which the certainty was greater than ‘unlikely’. Profenofos residues in water samples were reported in 1 3 of the incident reports (s ee Table 1 7 ). Of those incidents where profenofos re sidues were reported, 2 incidents had samples

with maximum residues < 1 ppb p rofenofos, 7 incidents had maximum measured residues between 1 and 10 ppb, 3 incidents reported residues between 10 and 100 ppb

, and 1 incident reported residues > 100 ppb. Although past and current registrations for profenofos have been

limited to use on cotton, 14 of the 23 incidents were reported for cotton use, while two of the areas were defined as agricultural areas

. T he remaining seven areas were undefined. Seven of the incidents were identified as following aerial application of profenofos (which is no longer permitted by the product label ), 1 incident was identified as following ground application of profenofos

, and the remaining 15 incidents did not identify the application method.

In addition to the incidents recorded in EIIS and AIMS, additio nal incidents have been reported to the Agency in aggregated incident reports. Pesticide registrants report certain types of incidents to the Agency as aggregate counts of incidents occurring per product per quarter. Ecological incidents reported in aggre gate reports include those categorized as ‘minor fish and wildlife’ (W

- B), ‘minor plant’ (P

- B), and ‘other non

- target’ (ONT) incidents. ‘Other non

- target’

incidents include reports of adverse effects to insects and other terrestrial invertebrates. For prof enofos , registrants have reported 4 minor fish and wildlife incidents, 0 minor plant incidents,

and 0 other non

- target incidents. These 4 aggregate incident reports were provided to the Agency

in 1998

- 1999. Unless additional information on these aggregate d incidents become available, they will be assumed to be representative of registered uses of profenofos in the risk assessment.

Although the number of reported incidents has dropped considerably since mitigation measures were implemented following the 20 00 IRED (USEPA, 2000), the lack of incident reports cannot be construed as the absence of incidents from the registered use of profenofos

. Reporting by states is only voluntary, and individuals discovering incidents may not be informed on the procedure of reporting these occurrences. Additionally, much of the se database s are generated from registrant

- submitted incident reports. In addition, incident reports for non

- target organisms typically provide information only on mortality events and plant damage inc idents. Impacts to

non

- commercial

, beneficial insects and other invertebrates are not likely to be reported. Except for phytotoxic effects in terrestrial plants, sublethal effects for organisms such as reduced growth or impaired reproduction are rarely re ported. Because of these logistical difficulties, EIIS is most likely a minimal representation of all pesticide

- related ecological incidents and the absence of incident reports cannot be construed as the absence of incident s

. However, the incident data

t hat are available suggest that exposure pathways for profenofos are complete and that exposure

levels are sufficient to result in field

- observable effects.

Table 16 . Summary of Ecological Incidents in the Environmental Incident Information System (EIIS 2 .1.1) Database A ssociated with P rofenofos Use, by C ertaintyPage 35 of 75

Incident Type Use Type Certainty

All (excluding unlikely) Unlikely Possible Probable Highly

Probable

Fish and Aquatic

Invertebrates Misuse

(accidental) 2 0 0 2 0

Registered Use 10 2 3 4 3

Unknown 11 1 4 4 3

Total 23 3 7 10 6

Table 1 7 . Summary of Ecological Incidents w ith Measured Profenofos Residues in the

EIIS Database

. Incident Number Year Location Certainty Profenofos Residues (ppb)

I001195

- 002 1994 Ouachita, LA 3 1.1

-- 12

I001195

- 001 1994 Richland, LA 3 1.3

— 2.3

I002211

- 001 1994 Rankin, MS 3 0.192

— 36.4

I004875

- 004 1996 Richland, LA 4 280

I004021

- 004 1996 Richland, LA 3 0.6

— 1.1 in water (up to 1,180 ppb in tissue)

I004021

- 005 1996 Richland, LA 3 0.7

— 1.5

I004468

- 010 1996 Madison, LA 2 0.2

— 1.2

I007948

- 007 1997 Holmes, MS 3 0.7

— 7.2

I007796

- 012 1997 Washington, MS 3 26.7

— 30.4

I008237

- 001 1998 Holmes, MS 3 1.2

— 1.8

I002211

- 003 1994 Humphreys, MS 3 0.4

— 0.7

I004668

- 008 1996 Richland, LA 2 0.08

— 3.58

I004668

- 009 1996 Richland, LA 2 0 .16

— 0.68

C ertainty Code: 0 = Unrelated, 1 = Unlikely, 2 = Possible, 3 = Probable, 4 = Highly Probable.

4. Risk Characterization

4.1. Risk Estimation

4.1.1. Aquatic Organisms

The peak EEC s in surface water generated from the SWCC model (using the ma ximum application

rate from cotton ) represents acute exposure to fish, aquatic invertebrates, and aquatic plants, and the highest 21

- day and 60

- day average EEC s represents chronic exposure to aquatic invertebrates

and fish , respectively

. Acute and chronic RQs for fresh water and estuarine/marine animals and aquatic vascular and nonvascular plants are summarized in Table 1 8

.

4.1.1.1

. FishPage 36 of 75

The listed and non

- listed species LOC’s were exceeded for acute risk to freshwater and estuarine/marine fish ( Table 15; RQs range from 0.73 to 1.34 ). Chronic data were not available for the most sensitive fish species (bluegill sunfish and pinfish), but chronic endpoints for these species, generated using the ACR developed from the acute and chronic fathead minnow

end points, resulted in exceedances of the fish chronic LOC for both freshwater and saltwater fish (RQs range from 12.0 to 21.2 )

.

4.1.1.2 Aquatic invertebrates

The listed and non

- listed species LOC’s were exceeded for acute risk to freshwa ter and

estuarine/m arine invertebrates (RQs range from 4.29 to 11.3 ). The aquatic invertebrate chronic LOC was exceeded for chronic risk to freshwater and estuarine/marine invertebrates (RQs ranged

from 23.0 to 25.3 )

.

4.1.1.3 Aquatic Plants

As shown in Table 1 8 , RQs for v ascular plants do not exceed the LOC (1.0) for listed or non

- listed plants for the currently registered use of profenofos (RQs ≤ 0.01). Risk to non

- vascular aquatic plants cannot be quantified due to a lack of adequate non

- vascular aquatic plant data.

Table 1 8

. Summary of Acute and Chronic RQs for Freshwater and Estuarine/Marine Fish,

Invertebrates and Aquatic P lants Exposed to Profenofos

Species Toxicity Endpoint (ppb) Maximum

EECs * Maximum

RQs

Freshwater Fish: Bluegill sunfish ( Lepomis macrochirus ) Acute 14.1 10.3 0.73

Chronic 0.23 2.75 12.0

Pinfish ( Lagodon rhomboids ) Acute 7.7 10.3 1.34

Chronic 0.13 2.75 21.2

Freshwater Invertebrates:

Waterflea ( Daphnia magna ) Acute 0.91 10.3 11.3

Chronic 0.2 5.05 25.3

Saltwater Invertebrates: Mysid shrimp (Americamysis bahia) Acute 2.4 10.3 4.29

Chronic 0.22 5.05 23.0

Aquatic Non

- Vascular Plant

No Data Non

- L isted No Data 10.3 N/A

Listed No Data 10.3 N/A
Aquatic Vascular Plants: Duckweed ( Lemna gibba ) Non

- listed 3,460 10.3 <0.01

Listed 1,270 10.3 0. 01

* EECs are estimated surface water concentrations based on SWCC model runs.

4.1.2. Terrestrial Org anisms

4.1.2.1. Birds

A valid NOAEC is not available for avian reproduction ; therefore, the chronic avian RQs presented

in Ta ble 19 use the LOAEC and are non

- definitive (“ greater than ”) m inimum RQs. Further

discussion of chronic risk to birds is provide d as part of the risk description in Section 4.2.2 as isPage 37 of 7 5

different acute endpoints for birds ( i.e. estimates of the avian acute oral LD 50 compared to the regurgitation NOAEC) and the effect of shorter foliar dissipation half

- lives based on the available

di slodgeable foliar residue data for profenofos

.

Using the regurgitation

- based NOAEC as a conservative acute endpoint for birds (the canary

NOAEC of 10 mg/kg

- bw and the test organism body weight of 21 .5 g)

, the maximum single and

annual application rate s with minimum reapplication intervals (10 applications at 0.5 lbs ai/A application with 5 day intervals )

, the default 35

- day foliar dissipation half

- life

, and the upper bound Kenaga residue values

, the acute listed species LOC (0.1) is exceeded for all siz e classes of birds feeding on all dietary items (RQs ranged from 0.18 to 92.10 ) and the non

- listed species LOC (0.5) was exceeded for all size classes of birds feeding on all dietary items except for large birds feeding on grains (RQ= 0.18 ). For medium siz ed birds feeding on grains, the exceedance was marginal (RQ= 0.57 ). Using the bobwhite sub

- acute dietary LC 50 of 57 mg/kg

- diet , the l isted

and non

- listed acute dietary LOCs are exceeded for birds consuming all dietary items ( 0.88

- 14.03 ). Similarly, using the non

- definitive NOAEC ( i.e. the NOAEC was less than the lowest dose tested) of 1 mg/kg

- diet for bobwhite, the chronic LOC (1.0) would be exceeded for birds consuming all dietary items ( RQs ranged from > 50 to >800)

. Using the de fault foliar dissipation

half

- life of 35 days, upper bound estimates of residues on dietary items results in exceedances for avian species that persist for up to approximately 220 days after the first application ( Appendix

G )

.

4.1.2.2 Mammals

Using the mouse acute LD 50 of 29 8 mg/kg

- bw for mammals and for the maximum single and annual application rates with minimum reapplication intervals (10 applications at 0.5 lb ai/ A application with 5 day intervals ) , the default 35

- day foliar dissipation half

- life and the upper bound Kenag a values, there were exceedances of the listed and non

- listed species acute LOCs (0.1 and 0.5, respectively) for all size classes of mammals for short grass and broadleaf plants (RQs range from 1.08 to 2.25 ). The listed and non

- listed species acute LOCs a re also both exceeded for small and medium mammals feeding on tall grass and arthropods (RQs range from

0.75

- 1.03 ), but only the listed species LOC is exceeded for large mammals feeding on these dietary items (RQs 0.40

- 0.47 ). The listed species acute LOC was marginally exceeded for small and medium mammals feeding on fruits/pods/seeds, but not for large mammals feeding on these dietary items (RQs 0.06

- 0.14 ) nor for any size class of mammal feeding on grain (RQs

0.01

- 0.03).

On a chronic dose basis, using the chronic rat NOAEC of 7.3 mg/kg

- diet, the LOC (1.0) is exceeded for all size classes of mammals consuming all dietary items (RQs range from 6.05 to 951). On a chronic dietary basis, the LOC is also exceeded for mammals consuming all dietary

item s (RQs range from 6.85 to 110 ).

Using the default foliar dissipation half

- life of 35 days and the minimum application interval

, upper bound estimates for terrestrial residues result in exc e edance s for mammalian herbivores,

insectivores and granivores that persist for up to approximately 280 days following the firstPage 38 of 75

profenofos application ( Appendix G )

. The effects of shorter half

- lives on the duration that exceedances persist post application are discussed in the risk description Section 4.2.2 below.

Tabl e 1 9

. Maximum Acute and Chronic Risk Estimates to Birds and Mammals fro m the Maximum Application Rates of Profenofos

Taxa Size

Class Dietary Items Resulting in Exceedances Cotton Use Site RQ’s 1

Acute: Dose

- Based

Birds 20 g Short grass, tall grass, broa dleaf plants, fruit/pods/seeds,

arthropods, grain

. 1.28

- 92.1

100 g Short grass, tall grass, broadleaf plants, fruit/pods/seeds,

arthropods, grain

. 0.57

- 41.3

1000 g Short grass, tall grass, broadleaf plants, fruits/pods/seeds,

arthropods , grain. 0.1 8

- 13.1

Mammals 15 g Short grass, tall grass, broadleaf plants, fruits/pods/seeds, arthropods 0.03

- 2.25

35 g Short grass, tall grass, broadleaf plants, fruits/pods/seeds,

arthropods 0.03

- 1.92

1000 g Short grass, tall grass, broadleaf plants, arth ropods 0.01

- 1.03 Acute: Dietary

- Based

Birds N/A Short grass, tall grass, broadleaf plants, fruit/pods/seeds, arthropods. 0.88

- 14.03

Chronic Dose

- Based

Mammals 15 Short grass, tall grass, broadleaf plants, fruit/pods/seeds, arthropods, grain

. 13.2

- 951

35 Short grass, tall grass, broadleaf plants, fruit/pods/seeds, arthropods, grain

. 11.3

- 812

1000 Short grass, tall grass, broadleaf plants, fruit/pods/seeds,

arthropods, grain

. 6.05

- 435

Chronic: Dietary

- Based

Mammals N/A Short grass, tall g rass, broadleaf plants, fruits/pods/seeds, arthropods. 6.85

- 109.6

Birds 2 N/A Short Grass, tall grass, broadleaf plants, fruits/pods, seeds, arthropods >50

- >800 2

1 RQs in bold exceed the non

- listed species LOC. RQs in bold italics exceed only the l isted species LOC.

2 Chronic bird RQs represent minimum RQs based on upper bound Kenaga residues and the avian reproduction LOAEC, since a chronic avian NOAEC is not available.Page 39 of 75 4.1 .2.3. Terrestrial Invertebrates

On an acute exposure basis, profenofos is classified as ‘ highly

- toxic ’ to non

- target terrestrial

insects including honey bees ( honey bee acute contact LD 50 = 0.0953 μg a.i./bee

. If an RQ were

calculated for terrestrial invertebrates 6

, using this LD 50 and determining acute contact exposure
fr om a direct spray of profenofos as the maximum single application rate (0.5 lbs a.i./A) * 2.7 μg

a.i./bee , the resultant RQ would be 14.2 or 1

- 2 orders of magnitude greater than the proposed terrestrial invertebrate LOC (0.4). Although this is for only a single application of profenofos, it may be considered an appropriate estimate of exposure from a direct spray as there is a 5 day minimum interval between applications and the lifespan of a forager bee is 4

- 5 days. However,

because the label prohibits pr ofenofos applications while bees are foraging in/or adjacent to the treatment area, this route of exposure would likely only occur from the drift of profenofos applications off the treated site. Since there is no acute or chronic oral toxicity data for adu lt or

larval bees and the magnitude of residue of profenofos in blooming cotton parts is unknown , the risk to adult bees from consumption of pollen or nectar with profenofos residues cannot b e determined in this assessment and is a major source of uncertai nty.

4.1.2.4. Plants

The RQs for terrestrial and semi

- aquatic plants for a single application of profenofos at the

maximum labeled rate of 5 lbs a.i./A is presented in Table 20

. RQs were not exceeded for either

listed and non

- listed monocots or dicots i n either dry or semi

- aquatic areas , though in semi

aquatic areas for dicots the listed LOC was only marginally not exceeded (RQ = 0.95). Risk from spray drift alone could not be evaluated due to the lack of vegetative vigor data using a

TEP.

Table 20 . R Q values for plants in dry and semi

- aquatic areas exposed to Profenofos through runoff*

Plant Type Listed Status Dry Semi

- Aquatic Spray Drift

Monocot non

- listed <0.1 0.11 N/A

Monocot listed <0.1 0.11 N/A

Dicot non

- listed 0.12 0.81 N/A

Dicot listed 0. 14 0.95 N/A

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

4.2. Risk Description

The results of this screening

- level risk assessment indicate that the registered use of profenofos

has the potential to cause dir ect adverse acute and chronic effects to freshwater and

estuarine/marine fish (and aquatic

- phase amphibians, for which fish are surrogates) and

invertebrates . Registered uses of profenofos are unlikely to cause adverse effects to vascular

6 The employed methodology for calculating an RQ for pollinators was first proposed in the 2012 Pollinator Risk Assessment Framework SAP White Paper, and subsequently validated by the panel. The White Paper is acce ssible online at regulations.gov, under docket EPA

- HQ

- OPP

- 2012

- 0543Page 40 of 75

aquatic plants, but risk is uncertain to non

- vascular aquatic plants. The results of the preliminary risk assessment also indicate that the registered use of profenofos has the potential to cause direct adverse acute and chronic effects to terrestrial mammals and birds ( and reptiles and terrestrial

phase amphibians, for which birds are surrogate s) except for all size classes of granivore mammals and large mammals consuming fruits, pods

, or seeds

. The preliminary risk assessment indicates

that risk to terrestrial monocots and dicots in dry and semi

- aquatic areas from runoff is unlikely, but risk of adverse effects due to spray drift is uncertain.

4.2.1 . Risks to Aquatic Organisms

Fish and Aquatic Invertebrates

Modeled EEC values result in exceedances of the listed a nd non

- listed species acute and chronic

LOCs for aquatic animals. For fish, the available data may underestimate the risk from profenofos

use, due to both uncertainties regarding the lack of sensitivity of the species tested as well as the

fact that nomin al concentrations without analytical measurements were used in the acute freshwater and estuarine/marine fish and acute freshwater invertebrate toxicity tests. For example, a qualitatively supplemental study with the spotted snakehead ( ECOTOX reference nu mber

E158179 ; using a profenofos formulation CELCRON that is not currently registered in the U.S.) indicated the species was >6x more sensitive than the bluegill on an acute basis with an LC 50 of 2.31 μg/L. The use of this endpoint would indicate that pea k EECs would be approximately 5 times the concentration that results in mortality of 50% of the test animals. The ACR of 61, generated from the acute and chronic fathead minnow data, applied to this endpoint would result in a chronic endpoint (0.038 μg/L) for the spotted snakehead that is nearly 2 orders of magnitude below the expected chronic EECs. This study also used nominal concentrations, so the actual concentrations of profenofos to which the snakehead was exposed to are uncertain, but may be

lower (resulting in a more sensitive LC 50 ) than described here.

Similarly, for aquatic invertebrates, the qualitatively supplemental open literature study with the

freshwater invertebrate Ceriodaphnia dubia ( ECOTOX reference number E 158195 ) indicated this speci es was >20x more sensitive than Daphnia magna on an acute basis with an EC 50 of 0.041 μg/L. The use of this endpoint would indicate that peak EECs would be >240 times the concentration that results in mortality of 50% of these test animals. An ACR of 4.5 , generated from the acute and chronic daphnid data, applied to the C. dubia acute endpoint would result in a chronic endpoint (0.009 μg/L) for C. dubia that is 2

- 3 orders of magnitude below the expected chronic EECs. This study also used nominal concentr ations, so the actual concentration of profenofos to which C. dubia was exposed to are uncertain, but may be lower (resulting in a more

sensitive EC 50 ) than described here.

No ecotoxicological data was available for benthic aquatic invertebrates; theref ore, RQs were not calculated for this taxa. However, the acute and chronic pore water EECs ( Table 9 ) indicate that benthic aquatic invertebrates would have to be approximately an order of magnitude more sensitive

than the available ecotoxicological data i ndicate for aquatic invertebrates in surface water in order to indicate greater risk to this taxa. Using the daphnid acute and chronic endpoints as surrogates for benthic invertebrate endpoints, the modeled pore water EECs would result in acute (RQ ~1.3)

a nd chronic (RQ ~ 3.5) risk to listed and non

- listed benthic invertebrate species.Page 41 of 75

The results from the QSAR analysis ( Appendix F ) also indicate that risk, especially on an acute

basis to freshwater and saltwater invertebrates and on a chronic basis to fres hwater fish and saltwater invertebrates, may be underestimated in this assessment if the O

- ethyl

- S

- propyl phosphorothioate metabolite is present , as this degradate was predicted to have similar acute toxicity to parent profenofos for aquatic invertebrates and similar chronic toxicity to parent for

freshwater fish and estuarine/marine invertebrates

. However, the stability of this degradate is

uncertain.

Although the last reported incident to fish and aquatic invertebrates was in 1999, before mitigation

mea sures were enacted following the 1999 RED, the peak and chronic modeled concentrations are similar to concentrations observed in water samples taken after many of the reported incidents

described in Section 3.2.3

.

Aquatic Plants

The calculated peak conc entrations are not expected to result in risk to vascular aquatic plants. Although quantitative data is not available for profenofos’ effects to non

- vascular aquatic plants,

the 72

- hour IC 50 and NOAEC to green algae (MRID 48612104) are approximately 1

- 1 .5 orders of magnitude above the peak EECs. Therefore, even if this study had been conducted for 96 hours, it may be unlikely that those endpoints would be 10

- 15x more sensitive than the 72

- hour endpoints. However, the study does indicate that non

- vasc ular aquatic plants may be more sensitive than vascular aquatic plants. Other algal species may also be more sensitive than the green algae and no data is available for other algal species including blue

- green algae and

freshwater and saltwater diatoms. A new non

- vascular aquatic plant study may reduce these

uncertainties , but this is not considered a major data gap

.

4.2.2 . Risks to Terrestrial Organisms

Based on the results of this preliminary a ssessment, the registered use of profenofos result s i n potential for direct acute and chronic effects to all size class and dietary combinations of birds and

mammals with the ex ception of granivore mammals and large mammals consuming fruits, pods

and seeds. Howev er, the risk assessment may be considered con servative due to the use of the default 35 day half

- life in T

- REX and the regurgitation

- based NOAEC as the acute endpoint for

birds

.

Only two studies are available with adequate foliar dissipation data, but they indicate that profenofos residues on foli age may dissipate considerably faster than the default rate. MRID

42851304 found the half

- life for residues in cotton grown in Texas to be 0.431 days, while MRID

42851303 found the half

- life for residues in cotton grown in California to be 0.711 days foll owing the single first order degradation pathway. These values were calculated using PestDF (USEPA,

2015 ). EFED has attempted to qualitatively characterize the potential risk to terrestrial organisms, using the more conservative of these values (0.711 da ys) , he re in the risk description section

. However, due to the uncertainty of only having two studies with adequate foliar dissipation data,

the final conclusions presented in the Executive Summary reflect the more conservative 35

- day

default assumption.Page 42 of 75

Birds The regurgitation

- based NOAEC of 10 mg/kg

- bw for the canary is a highly conservative surrogate

for the LD 50 endpoint. At this dosage, there was 0% mortality in the acute study with canary (MRID 48612102). An LD 50 of 40.8 mg/kg

- bw (95% Confidence I ntervals of 18.3

— 57.4 mg/kg

bw) was estimated from this study by removing the 20 mg/kg

- bw treatment group, which was the only treatment group reported to exhibit regurgitation of the test substance. However, due to the assumption of allometric scaling of t oxicity by body weight, the mallard LD 50 of 55.0 mg/kg

- bw is considered a more sensitive estimate of the acute endpoint than the estimated canary acute LD 50 ; the mallard endpoint also has less uncertainty associated with it.

If the half

- life from the California study is used (0.711 days) in place of the default 35 day half

life and the mallard LD 50 is used instead of the regurgitation

- based NOAEC, th e n for birds on an acute basis , the listed species acute dose

- based LOC (0.1) would still be exceeded f or small and medium birds feeding on all dietary items except for grain (RQs would range from 0.03 to 4.82 ) and for large birds feeding on all dietary items except for grain and fruits/pods/seeds (RQs would range from 0.01 to 4.82 ).

Using identical assu mptions, the non

- listed species acute dose

- based LOC (0.5) would still be exceeded for all sizes of birds feeding on short grass (RQs 0.68

- 4.82 ) and small and medium birds feeding on tall grass, broadleaf plants and arthropods (RQs 0.85

- 2.71 ), but woul d not be exceeded for large birds feeding on any dietary item other than short grass or for small and medium birds feeding on grain or fruits, pods and seeds. On an acute dietary basis and using the half

- life from the California study , the listed species L OC would also still be exceeded for birds consuming all dietary items and the non

- listed species LOC would still be exceeded for birds consuming all dietary ite ms other than fruits/pods/seeds (RQs would range from 0.13 to 2.12 ) and the chronic dietary

- base d LOC would still be exceeded for birds feeding on all dietary items (RQs would range

from > 7.56 to > 121 ).

As the chronic avian reproduction test was unable to define a NOAEC, the chronic avian RQs are

nondefinitive and chronic risk is likely to be grea ter than identified here. In the past, EFED has

used the MCnest model tool (USEPA, 2013) as a Tier 2 model to further refine chronic risk to birds and determine potential application timings that would mitigate chronic risk to birds. However, the lack of an acceptable NOAEC value precludes the use of this model to refine risk. Using the California study’s foliar dissipation half

- life of 0.711 days and the minimum application interval, upper bound Kenaga estimates for terrestrial residues result in expecte d residues remaining higher than the relevant dietary toxicity endpoints ( Appendix G ) for a much shorter time period of less than 50 days compared to the ~2 2 0 days when utilizing the default 35 day half

life.

Mammals

I f the half

- life from the California s tudy is used (0.711 days) in place of the default 35 day half

life, then on an acute dose

- basis the non

- listed species LOC would not be exceeded for any size mammals feeding on any dietary item ; while the listed species LOC would only continue to be

exceed ed for all sizes of mammals consuming short grass (RQs would range from 0.16 to 0. 34 ) and for small and medium sized mammals feeding on tall grass, broadleaf plants and arthropodsPage 43 of 75

(RQs would range from 0.11

- 0.19 ). However, even with this shorter half

- li fe , the chronic dietary

LOC would continue to be exceeded for mammals consuming all dietary items (RQs would range

from 1.04 to 16.56 ) and the chronic dose

- based LOC would continue to be exceeded for all size classes of mammals consuming all dietary items except for large granivore mammals (RQs would range from 0.91 to 115 )

. Using the 0.711 day foliar dissipation half

- life, the upper bound Kenaga estimates for terrestrial residues result in expected residues remainin g higher than the relevant dietary toxic ity endpoints for a much shorter time period of less than 50 days compared to the ~280 days when utilizing the default 35 day half

- life ( Appendix G ).

Terrestrial Invertebrates Only acute contact toxicity data is avail able for honey bee s. The proposed LOC (0.4) for beneficial terrestrial invertebrates is exceeded by more than a n order of magnitude

. The current label language may mitigate some risk on an acute contact basis to honey bees since it prohibits treatment while bees are foraging in/or adjacent t o the treatment area. However, other, non

- Apis bees and other beneficial insects may still be at risk as their presence may be less conspicuous to the pesticide applicator. Additionally, dietary risk to bees cannot be precluded due to the lack of

acute a nd chronic oral data with adult honey bees. Similarly, h azard to potentially sensitive life stages ( i.e. egg s , larvae and juveniles) may not be evident from the honey bee contact toxicity test

that used adult worker honey bee s.

Terrestrial Plants

The EE Cs predicted by EFED’s current screening tool, Terr P lant

, indicated no risk to listed and

non

- listed species of monocots and dicots in either semiaquatic or dry habitats . Risk from s pray drift alone could not be quantitatively evaluated due to the lack of vegetative vigor data with a TEP. However, vegetative vigor endpoints from a TEP would have to be 22 times more sensitive

than the submitted seedling emer gence study NOAEC in order to result in exceedances of the listed species LOC from spray drift alone according to the TerrPlant model

. Al though that seedling

emergence study was also conducted with TGAI and may underestimate a formulation’s toxicity

, this is less of a concern for seedling emergence studies since adjuvants and surfactants in the TEP

are e xpected to disassociate from the active ingredient prior to the seeds’ exposure

.

However, it should be noted that the Terr P lant screening level analysis actually evaluates the risk

to off

- field plants based on runoff and spray drift fractions. Given that the seedling emergence NOAEC (0.111 lb a.i./A) for the most sensitive species, cucumber, is below the single maximum application rate (0.5 lb a.i./A), there is some potential for risk to listed species occurring on the

field.

Risk to Off

- Field Nontarge t Organisms due to Spray Drift

Spray drift exposures from the registered profenofos applications can be an exposure pathway and aerial applications will result in larger areas off the application site where sensitive taxa ( e.g. aquatic and terrestrial inv ertebrates and birds) may be exposed. Concentrations of 0. 046 μg/L in water trigger the acute listed species LOC of 0.05 (based on the daphnid acute LD 50 of 0.91 μg/L).Page 44 of 75

Concentrations on land over 0.0139 lb a.i./A exceed the LOC (0.4) for beneficial terr estrial invertebrates, based on the honey bee acute contact LD 50 of 0.0953 μg/bee and using the proposed upper bound residue value of 2.7 μg a.i./bee for a 1 lb a.i./A application (USEPA, 2014 a based on work from Koch and Weisser, 1997)

. Concentrations o n land over 0.01 lbs a.i./A exceed the listed species LOC (0.1) for avian species, based on the mallard acute LD 50 of 55 mg a.i./kg

- bw, A full range of the output of this model with distances from the edge of field to an exceedance of the

LOC under a varie ty of application parameters is described in Appendix H

.

Spray drift exposure to profenofos was determined using AgDrift 2.1.1 and the maximum foliar single application rate (0.5 lb a.i./A). The distance to the EPA

- defined Pond from the edge of field

was determined for an initial average concentration of 0.046 μg/L in Tier I Ground A qu atic

A ssessments. Using initial conservative conditions of high boom and nozzles producing very fine

fine droplet spectra, the RQ from spray drift alone exceeds the listed species LOC for aquatic

invertebrates at distances less than 810 feet. Using more refined application parameters (low boom, nozzles producing a droplet size distribution of fine to medium/coarse ) , the RQ from spray

drift alone exceeds the listed species L OC for aquatic invertebrates at distances less than 265 feet.

For off

- field beneficial terrestrial invertebrates, the distance was calculated from the edge of the applied field to a point where deposition of profenofos residues drops below 0.0139 lb a.i ./A in Tier I Ground Terrestrial Assessments. Using initial conservative conditions of high boom and nozzles producing very fine

- fine droplet spectra, the RQ from spray drift alone exceeds the non

listed species LOC (0.4) at distances less than 90 feet. Using more refined application parameters (low boom, nozzles producing fine to medium droplet spectra), the RQ from spray drift alone

exceeds the non

- listed species LOC at distances less than 10 feet.

For off

- field birds, the distance was calculated fro m the edge of the applied field to a point where deposition of profenofos residues from spray drift would drop below 0.01 lb a.i./A in Tier I Ground

Terrestrial Assessments. Using initial conservative conditions of high boom and nozzles producing very fin e

- fine droplet spectra, the RQ from spray drift alone exceeds the listed species LOC (0.1) at distances less than 125 feet. Using more refined application parameters (low boom, nozzles producing fine to medium droplet spectra), the RQ from spray drift alo ne exceeds the non

listed species LOC at distances less than 15 feet.

5. Federally Threatened and Endangered (Listed) Species Concerns

Based on this screening

- level assessment, there are potential risks of direct effects to listed fish, amphibians, aq uatic invertebrates, birds, reptiles, mammals and terrestrial invertebrates from the

use of profenofos on some of its registered use sites. Listed species of these taxa may also be affected through indirect effects because of the potential direct effects on listed and non

- listed species. Potential direct effects on listed fish, amphibians, aquatic invertebrates, birds, reptiles,

mammals and terrestrial invertebrates from the use of profenofos may be associated with

modification of P rimary C onstituent E lem ents (PCEs) of designated critical habitats, where such designations have been made. However, a t this stage of the Registration Review process, it is premature to make effects determinations for listed species until further scientific analysis and

refinem ents are conducted , based on recommendations received from the National Academy ofPage 45 of 75

Sciences’ (NAS) National Research Council (NRC) April 2013 report, available at http://www.nap.edu/catalog.php? record_id=18344 . The NAS report outlines recommendations on specific scientific and technical issues related to the development of pesticide risk assessments that are compliant with the Endangered Species Act (ESA) and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

The EPA along with the U.S. Fish & Wildlife Service (USFWS), the National Marine Fisheries Service (NMFS) (collectively, the Services), and the U.S. Department of Agriculture (USDA), released a summary of their implementation plan for assessing risks of pesticides to listed species ahead of the stakeholder workshop held on November 15, 2013. This plan was developed in response to the NAS’ recommendations, including a common approach to risk assessment as a way of addressing s cientific differences between EPA and the Services. During the workshop, the agencies received feedback from the public on the interim scientific approaches that were developed as part of the initial implementation of the NAS recommendations. These appro aches will be jointly implemented and vetted as part of a phased iterative process. Once fully vetted, EPA will further refine the listed species effects determination portion of this risk assessment.

To make effects determinations for individual liste d species, useful refinements may include, but are not limited to, analyses of: 1) more detailed, species

- specific ecological and biological data; 2) more detailed and accurate information on profenofos use patterns; and 3) sub

- county level spatial proximi ty data for the co

- occurrence of potential effects areas and listed species and any designated critical habitat. Examples of such refinements are described below.

EFED is currently developing tools that are expected to further refine the assessment and a re designed to support effects determinations for individual federally listed species and their designated critical habitats (where applicable). Scientific information obtained from the

Services , and other reliable sources is being collated by EFED to add ress all currently listed species. Th is information is be ing stored in an Office of Pesticide Programs (OPP) P esticide

R egistration I nformation S yste M (PRISM) listed species knowledgebase. The listed species knowledgebase consist s of an information repos itory that houses biological and behavioral information relevant to individual species ( e.g. , habitat, diet, and life history, including specific temporal and spatial associations) and a document repository that contains supporting documents ( e.g ., USFWS r ecovery plans) and electronic information ( e.g ., GIS data files). For terrestrial taxa, biological information relevant to the assessment ( e.g ., diet and body weight) will be used to parameterize exposure estimates using a method consistent with currently used methods in the

T

- REX and T

- HERPS models.

Refinements will also include more detailed analyses of the registered uses and specific use patterns that result in either “Likely to Adversely Affect” (LAA) or “Not Likely to Adversely Affect” (NLAA) dete rminations for federally listed species. The analyses may include more information on where, when, and how profenofos is used on cotton

. Actual usage data (when available) and national land

- cover datasets that indicate potential use sites [ e.g ., N ational L and

C over D ataset (NLCD), C rop land D ata L ayer (CDL)] may be used to support a more refined analysis of where profenofos is reasonably expected to be used. Similarly, refinements on thePage 46 of 75

timing of applications and a more in

- depth exploration of agronomic practices for profenofos may be included as part of the refinement.

The refinements based on individual species data; additional, detailed usage information, when available; and recommendations from the NRC report are expected to help to more accurately

i dentify potential areas of effect and to better inform effects and habitat determinations for listed species and any designated critical habitats.

Based on previous fish kills, use of profenofos is restricted in Reeves County, Texas and near

Dexter Nation al Fish Hatchery in NM to protect listed fish species.

The federal action addressed herein is the proposed renewed registration of profenofos on agricultural use sites , primarily in southern cotton

- growing states . It is expected that its use could

occur nationwide in cotton

- growing states.

5.1. Action Area

For listed species assessment purposes, the action area is considered to be the area affected directly or indirectly by profenofos use and not merely the immediate area wh ere profenofos is applied. At the initial baseline, the risk assessment considers broadly described taxonomic groups and conservatively assumes that listed species within those broad groups are co

- located with the pesticide treatment area. This means tha t listed terrestrial plants and wildlife are assumed to be located on or adjacent to the treated site and listed aquatic organisms are assumed to be located in a surface water body adjacent to the treated site. The assessment also assumes that the listed species are located within an assumed area, which has the relatively highest potential exposure to the pesticide, and that exposures are likely to decrease with distance from the treatment area.

Generally, the action area for profenofos is limited to th ose areas of the US where cotton is grown. This may include southern California, Arizona, New Mexico, Texas, Oklahoma, M i ssouri, Arkansas, Tennessee, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, and Virginia.

5.2. Taxonomic Gr oups Potentially at Risk

If the assumptions associated with the baseline action area result in RQs that are below the listed species LOCs, a "no effect" determination conclusion is made with respect to listed species in that taxa, and no further refinement of the action area is necessary. Furthermore, RQs below the listed species LOCs for a given taxonomic group indicate no concern for indirect effects on listed species that depend upon the taxonomic gr oup for which the RQ was calculated. However, in situations where the screening assumptions lead to RQs in excess of the listed species LOCs for a given taxonomic group, a potential for a "may affect" conclusion exists and may be associated with direct

ef fects on listed species belonging to that taxonomic group or may extend to indirect effects upon listed species that depend upon that taxonomic group as a resource. In such cases, additional information on the biology of listed species, the locations of t hese species, and the locations of use sites are considered to determine the extent to which screening assumptions regarding an actionPage 47 of 75

area apply to a particular listed organism. These subsequent refinement steps will consider how

this information would i mpact the action area for a particular listed organism and potentially include areas of exposure that are downwind and downstream of the pesticide use site.

Assessment endpoints, exposure pathways, and the conceptual models addressing profenofos uses, and the associated exposure and effects analyses conducted for the profenofos baseline risk

assessment are in Sections 2 to 3 . The assessment endpoints used in the baseline risk assessment include those defined operationally as reduced survival and reproduct ive impairment for both aquatic and terrestrial animal species and survival, reproduction, and growth of aquatic and terrestrial plant species from both direct acute and chronic exposures. These assessment endpoints

are intended to address the standard se t forth in the Endangered Species Act requiring federal agencies to ensure that any action they authorize does not appreciably reduce the likelihood of both the survival and recovery of a listed species in the wild by reducing the reproduction, numbers, or distribution of the species. Risk estimates (RQs) which, integrating exposure and effects, are calculated for broad based taxonomic groups in the screening

- level risk assessment presented in Section 4.

Both acute endangered species and chronic risk LOCs are considered in the baseline risk assessment to identify direct and indirect effects to taxa of listed species. This section identifies direct effect concerns, by taxa that are triggered by exceeding endangered LOCs in the baseline risk assessment, wit h an evaluation of the potential probability of individual effects for exposures that may occur at the established endangered species LOC. Data on exposure and effects collected under field and laboratory conditions are evaluated to make determinations on the predictive utility of the direct effect screening assessment findings to listed species. Potential for direct effects to

listed taxa are described in Table 21

.

Table 21 . Potential Effects to Federally Listed Taxa Associated with Direct Effects fro m th e Registered Use of Profenofos

. Listed Plant Taxon Potential Direct Effects

Terrestrial and semi

- aquatic plants

– monocots and dicots No

Aquatic nonvascular plants 1 No Aquatic vascular plants No

Listed Animal Taxon Potential Direct Effects

Acute Chronic

Terrestrial invertebrates Yes Uncertain 2

Mammals Yes Yes

Birds Yes Yes Reptiles Yes Yes Amphibians 3 Yes Yes

Freshwater fish Yes Yes

Freshwater invertebrates Yes Yes

Estuarine/marine fish Yes Yes

Estuarine/marine invertebrates Yes Yes

1 T here are currently no listed species of aquatic non

- vascular plants.

2 C hronic risk to listed species of terrestrial invertebrates is uncertain due to the lack of chronic data for juvenile and adult honey bees.

3 Acute and chronic risk to this taxa is expe cted for both the terrestrial and aquatic

- phase in the amphibian life cycle.Page 48 of 75

6 . Literature Cited

Fletcher, J.S., J.E. Nellesson and T.G. Pfleeger. 1994. Literature review and evaluation of the

EPA food

- chain (Kenaga) nomogram, an instrument for estim ating pesticide residues on plants.

Environ. Tox. And Chem. 13(9):1383

- 1391.

Hoerger, 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: F. Couls ton and F. Corte, eds., Environmental Quality and Safety: Chemistry, Toxicology and Technology. Vol 1. George Theime Publishers, Stuttgart, Germany. pp. 9

- 28.

Koch, H. and P. Weisser. 1997. Exposure of honey bees during pesticide application under field

conditions. Apidologie . 28: 439

— 447.

Leader, H. and J.E. Casida. 1982. Resolution and Biological Activity of the Chiral Isomers of O

- (4

- Bromo

- 2

- chlorophenyl) O

- Ethyl S

- Propyl Phosphorothioate (Profenofos Insecticide). J. Agric.

Food Chem. 30: 546

— 551.

Liu, J. and X. Zhang. 2014. Comparative toxicity of new halophenolic DBPs in chlorinated saline wastewater effluents against a marine alga: Halophenolic DBPs are generally more toxic than haloaliphatic ones. Water Research . 65: 64

— 72.

Mayer

, F

. L . a nd M.R. Ellersieck

. 1986. Manual of acute toxicity: Interpretation and database for 410 chemicals and 66 species of freshwater animals (resource publication no. 160). United States

Fish and Wildlife Service, Washington, DC

. MRID 400980

- 01

.

National Resear ch Council. 2013. Assessing Risks to Endange red and Threatened Species from Pesticides. Committee on Ecological Risk Assessment under FIFRA and ESA, Board on Environmental Studies and Toxicology, Division on Earth and Life Studies, National Research

Counc il of the National Academies. The National Academies Press, Washington, DC.

Pandey, A.K., N.S. Nagpure, S.P. Trivedi, R. Kumar, B. Kushwaha and W.S. Lakra. 2011. Investigation on acute toxicity and behavioral changes in Channa punctatus (Bloch) due to

org anophosphate pesticide profenofos. Drug and Chemical Toxicology . 34(4): 424

— 428.

Ecotox Reference Number E158179.

USEPA, 1998. Guidelines for Ecological Risk Assessment. Risk Assessment Forum, U.S. Environmental Protection Agency. Washington, D.C. Ma y 14, 1998. Federal Reigster 63(93):

26846

— 26924.

USEPA, 1999. Rere gistration Eligibility Decision Environmental Risk Assessment for Profenofos. Environmental Fate and Effects Division, Office of Pesticide Programs, Office of Prevention, Pesticides, a nd Toxic Substances. Washington, DC. June 16, 1999.Page 49 of 75

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. Offi ce of Pesticide Programs. Washington, D.C. January 23, 2004.

USEPA, 2009. Input Parameter Guidance. Version 2.1. Environmental Fate and Effects Division. October 22, 2009 http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

USEPA, 2013. User’s Manual for Basic Version of MCnest

— Markov Chain Nest Productivity

Model. Mid

- Continent Ecology Division, National Health and Environmental Effects Research

L aboratory, Office of Research and Development, U.S. Environmental Protection Agency. Duluth, MN. February, 2013.

USEPA, 2014a. Guidance for Assessing Pesticide Risks to Bees. Environmental Fate and Effects Division. Office of Pesticide Programs. Washing ton, D.C. June 23, 2014.

USEPA, 2014 b . Profenofos : General Information on its Use and Alternatives to Support Registration Review. Biological and Economic Analysis Division. Office of Pesticide Programs. Washington, D.C. August 19, 2014.

USEPA, 201 5. Standard Operating Procedure for Using the NAFTA Guidance to Calculate Representative Half

- life Values and Characterizing Pesticide Degradation. Office of Pesticide Programs, U.S. Environmental Protection Agency. March, 23, 2015.

USFWS, 1989. U.S. Fish and Wildlife Service Biological Opinion on Selected Pesticides. U.S. Fish and Wildlife Service. September 14, 1989.

Willis and McDowell. 1987. Pesticide persistence on foliage. Environ. Contam. Toxicol. 100:23

- 73.

Woods, M., A. Kumar and R. Correl l. 2002. Acute Toxicity of Mixtures of Chlorpyrifos, Profenofos, and Endosulfan to Ceriodaphnia dubia

. Bull. Environ. Contam. Toxicol . 68: 801

— 808. Ecotox Reference Number: E158195Page 50 of 75 

### Appendix A

– Summary of Risk Conclusions by Taxa

Use Pattern Category Aquatic

Invertebrates Fish (surrogate

for aquatic

phase amphibians) Birds, (surrogate for

terrestrial

- phase amphibians and reptiles) Mammals Plants Beneficial

Terrestrial

Invertebrates

Cotton Acute risk:

Expected for

both listed and

non

- listed species, both

from runoff and through spray drift.

Chronic risk : Expected. Acute risk:

Expected for

both listed and

non

- listed species.

Chronic risk : Expected Acute risk :

Dose

- and dietary

- based risk to all listed species regardless of size class or dietary

c o nsumption. Dose

- based

risk to non

- listed birds species of all size classes consuming all dietary items except for large birds consuming grain.

Chronic risk : Expected for all size classes regardless of diet. Acute risk: Risk to listed species of all

si ze classes consuming short grass, tall grass, broadleaf plants and arthopods. Risk not expected for granivores or mammals consuming fruits/seeds/pods. Risk to

non

- listed species only for

small and medium mammals consuming short grass and broadleaf plants

and small mammals consuming tall grass.

Chronic risk : Expected for all size classes, regardless of diet. Terrestrial: Risk considered unlikely for

off

- field terrestrial plants from

runoff. There is some potential for risk to listed species occurring o n the agricultural field.

Risk is somewhat uncertain for plants exposed to spray drift, but is not considered likely.

Aquatic: Not expected Acute risk : Expected for listed

and non

- listed species on a contact

basis. Uncertain for

listed and non

- liste d species from oral exposure to residues in pollen and nectar.

Chronic risk : Uncertain for listed

and non

- listed species from oral exposure to residues in pollen and nectar

.Page 51 of 75



### Appendix B

— Input Parameters and Output for the STIR model



## Welcome to the EFED Screening Tool for Inhalation Risk

This tool is designed to provide the risk assessor with a rapid method for determining the potential significance of the inhalation exposure route to birds and mammals in a risk assessment.



## Input

A pplication and Chemical Information

Enter Chemical Name Profenofos

Enter Chemical Use Cotton Is the Application a Spray? (enter y or n) y If Spray What Type (enter ground or air) ground Enter Chemical Molecular Weight (g/mole) 373.63

En ter Chemical Vapor Pressure (mmHg) 9.30E

- 07 Enter Application Rate (lb a.i./acre) 0.5

Toxicity Properties

Bird

Enter Lowest Bird Oral LD 50 (mg/kg bw) 55 Enter Mineau Scaling Factor 1.15 Enter Tested Bird Weight (kg) 21.5

Mam mal

Enter Lowest Rat Oral LD 50 (mg/kg bw) 300

Enter Lowest Rat Inhalation LC 50 (mg/L) 3.6 Duration of Rat Inhalation Study (hrs) 4 Enter Rat Weight (kg) 0.35



## Output

Results Avian (0.020 kg )
Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.87E

- 02

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 2.35E

- 03

Adjusted Inhalation LD 50 1.79E+00

Ratio of Vapor Dose to Adjusted Inhalation LD 50 1.31E

- 03 Exposure not Likely Significant

Maximum Post

- treatment Spray Inh alation Dose (mg/kg) 5.28E

- 02 Ratio of Droplet Inhalation Dose to Adjusted Inhalation

LD 50 2.95E

- 02 Exposure not Likely Significant

Results Mammalian (0.015 kg )Page 52 of 75

Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.87E

- 02

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 2.95E

- 03

Adjusted Inhalation LD 50 2.14E+02

Ratio of Vapor Dose to Adjusted Inhalation LD 50 1.38E

- 05 Exposure not Likely Significant

Maximum Post

- treatment Spray Inhalation Dose (mg/kg) 6.64E

- 02 Ratio of Drop let Inhalation Dose to Adjusted Inhalation

LD 50 3.10E

- 04 Exposure not Likely SignificantPage 53 of 75



### Appendix C

— Chemical Structure and Characteristics of Profenofos Degradates

Degradate Structure Study Max [%] Time (days)

4

- bromo

- 2

- chlorophenol (CGA

- 55960) Hy drolysis

41627309 4.9% (pH 5) 30

23.0% (pH 7) 30

80.2% (pH 90 1

41939001 8.8% (pH 5) 30

51.6% (pH 7) 30

89.7% (pH 9) 1

Aerobic Soil Metabolism

42334302 72.5%

- 79.7%

(pH 7.8) 5

- 120

Anaerobic Soil Metabolism

42334302 82.5 0% 60

Anaerobic Aquatic Metabolism

SMILES: C1=CC(=C(C=C1Br)Cl)O 42218101 67.6%

- 81.2% 6

- 180

O

- ethyl

- S

- propyl phosphorothioate Hydrolysis

41627309 formed in equimolar

proportions with CGA

55960 SMILES: CCCSP(=O)(O)OCC 41939001

4

- bromo

- 2

- chlorophenyl ethyl ether (BCPEE) Aerobic Soil Metabolism

42334302 41.7%

- 42.6%

(pH 7.8) 270

- 360

Anaerobic Soil Metabolism

42334302 2.70% 60

Anaerobic Aquatic Metabolism

SMILES: C1=CC(=CC(=C1OCC)Cl)Br 42218101 8.3%

- 20.2% 60

- 360

2

- th ioethylenecarboxy

- 4

- hydroxyphenyl methyl ether (THPME) Aerobic Soil Metabolism

SMILES: C1=C(C=C(C(=C1)OC)SCCC(=O)O)O 42334302 9.9%

- 10% 180

- 270Page 54 of 75

2

- mercapto

- 4

- hydroxyphenyl methyl ether (MHPME) Aerobic Soil Metabolism

SMILES: C1=CC(=CC(=C1OC)S) O 42334302

4.30% 30

4

- bromo

- 2

- chlorophenyl methyl ether (BCPME) Aerobic Soil Metabolism

SMILES: C1=CC(=CC(=C1OC)Cl)Br 42334302
2.40% 180

chlorophenol

- glucose conjugate (CP

- G) Aerobic Soil Metabolism

42334302 1.90% 30

SMILES: C1=CC=CC(=C1OCC 2C(C(C(C(O2)O)O)O)O)ClPage 55 of 75



### Appendix D . Example Input and Outputs for the SIP Model

Table 1. Inputs

Parameter Value

Chemical name Profenofos

Solubility (in water at 25 o C; mg/L) 20

Mammalian LD 50 (mg/kg

- bw) 298

Mammalian test spec ies other
Body weight (g) of "other" mammalian species 25

Mammalian NOAEL (mg/kg

- bw) 0.365

Mammalian test species laboratory rat
Body weight (g) of "other" mammalian species

Avian LD 50 (mg/kg

- bw) 55
Avian test species othe r Body weight (g) of "other" avian species 1580
Mineau scaling factor 1.15

Mallard NOAEC (mg/kg

- diet)
Bobwhite quail NOAEC (mg/kg

- diet) 1
NOAEC (mg/kg

- diet) for other bird species
Body weight (g) of other avian species

NOA EC (mg/kg

- diet) for 2nd other bird species
Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg

- bw) 3.4400 3.4400
Adjusted toxicity value (mg/kg

- bw) 118.4953 0.280 7
Ratio of exposure to toxicity 0.0290 12.2532

Conclusion* Drinking water exposure alone is NOT a potential concern for

mammals Exposure through drinking water alone is a potential
concern for mammals

Table 3. Avian Results

Parameter Acute C hronic

Upper bound exposure (mg/kg

- bw) 16.2000 16.2000
Adjusted toxicity value (mg/kg

- bw) 28.5574 0.1063
Ratio of exposure to acute toxicity 0.5673 152.4013

Conclusion* Exposure through drinking water alone is a potential concern for

birds Exposure thr ough drinking water alone is a potential
concern for birds

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when aggregated with other routes ( i.e ., diet, inhalation, dermal), pesticide exposure through drinking water may contribute to a total exposure that has potential for effects to non

- target animals.Page 56 of 75



### Appendix E . Example Input and Outputs for the KABAM Model

Table 1. Chemical characteristics of Profenofos.

Characteristic Value Comments/Gu idance

Pesticide Name Profenofos Required input

Log K OW 4.83 Required input Enter value from acceptable or supplemental study submitted by registrant or available in scientific literature.

K OW 67608 No input necessary. This value is calculated automati cally from the Log K OW value entered above.

K OC (L/kg OC) 3890 Required input Input value used in PRZM/EXAMS to derive EECs. Follow input parameter guidance for deriving this parameter value (USEPA 2002).

Time to steady state (T S ; days) 21 No input necessary. This value is calculated automatically from the Log K OW value entered above.

Pore water EEC (μg/L) 0.753 Required input Enter value generated by PRZM/EXAMS benthic file. PRZM/EXAMS EEC represents the freely dissolved

conce ntration of the pesticide in the pore water of the sediment. The appropriate averaging period of the EEC is dependent on the specific pesticide being modeled and is based on the time it takes for the chemical to reach steady state. Select the EEC generated by PRZM/EXAMS which has an averaging period closest to the time to steady state calculated above. In cases where the time to steady state exceeds 365 days, the user should select the EEC representing the average of yearly averages. The peak
EEC should no t be used.

Water Column EEC (μg/L) 5.05 Required input Enter value generated by PRZM/EXAMS water column file. PRZM/EXAMS EEC represents the freely dissolved concentration of the pesticide in the water column. The appropriate averaging period of the EEC is dependent on the specific pesticide being modeled and is based on the time it takes for the chemical to reach steady state. The averaging period used for the water column EEC should be the same as the one selected for the pore water EEC (discussed abov e).

Table 2. Input parameters for rate constants. "calculated" indicates that model will calculate

rate constant.

Trophic level k 1 (L/kg*d) k 2

(d

- 1 ) k D

(kg

- food/kg

org/d) k E

(d

- 1 ) k M *

(d

- 1 )Page 57 of 75

phytoplankton calculated calculated 0* 0* 0
zooplankton calculated calculated calculated calculated 0

benthic invertebrates calculated calcul ated calculated calculated 0

filter feeders calculated calculated calculated calculated 0

small fish calculated calculated calculated calculated 0

medium fish calculated calculated calculated calculated 0 large fish calculated calculated calculated cal culated 0

* Default value is 0.

k 1 and k 2 represent the uptake and elimination constants respectively, through respiration.

k D and k E represent the uptake and elimination constants, respectively, through diet.

k M represents the metabolis m rate constant.

Table 3. Mammalian and avian toxicity data for Profenofos. These are required inputs.

Animal Measure of effect (units) Value Species If

selected species is "other,"

enter body weight (in kg) here.

Avian LD 50 (mg/kg

b w) 55 mallard duck

LC 50 (mg/kg

diet) 57 Northern bobwhite quail

NOAEC (mg/kg

- diet) 1 Northern bobwhite quail

Mineau Scaling

Factor 1.15 Default value for all species is 1.15 (for chemical specific values, see Mineau et al.

1996).

Mammalia n LD 50 (mg/kg

bw) 298 other 0.025
LC 50 (mg/kg

diet) N/A other

Chronic Endpoint 7.3 laboratory rat

units of chronic endpoint* ppm

Table 11. Estimated concentrations of Profenofos in ecosystem components.Page 58 of 75

Ecosystem Component Total

concen tration (μg/kg

- ww) Lipid

normalized

concentration (μg/kg

- lipid) Contribution

due to diet (μg/kg

- ww) Contribution

due to respiration (μg/kg

- ww)
Water (total)* 5 N/A N/A N/A Water (freely dissolved)* 5 N/A N/A N/A Sediment (pore water)* 1 N/A N/A N/ A Sediment (in solid)** 117 N/A N/A N/A
Phytoplankton 15,674 783681 N/A 15,673.63 Zooplankton 11,892 396409 254.78 11,637.50

Benthic Invertebrates 12,718 423933 640.86 12,077.12

Filter Feeders 8,355 417769 412.81 7,942.57

Small Fish 18,02 8 450711 2,743.83 15,284.59

Medium Fish 20,241 506014 5,307.86 14,932.69 Large Fish 25,798 644956 10,713.00 15,085.26
* Units: μg/L; **Units: μg/kg

- dw

Table 12. Total BCFand BAF val ues of Profenofos in aquatic trophic levels. 0 5000 10000 15000 20000 25000 30000

Zooplankton Benthic

Invertebrates Filter Feeders Small Fish Medium Fish Large Fish Concentration (μg/kg)

Trophic Level

Figure 1. Total pesticide concentration

per trophic level Contribution due to respiration (μg/kg-ww)

Contribution due to diet (μg/kg-ww)Page 59 of 75 Trophic Level Total BCF (μg/kg

ww)/(μg/L) Total BAF

(μg/kg

ww)/(μg/L)
Phytoplankton 3246 3104 Zooplankton 2313 2355

Benthic Invertebrates 2418 2518

Filter Fee ders 1590 1655

Small Fish 3111 3570

Medium Fish 3111 4008 Large Fish 3249 5109

Table 13. Lipid

- normalized BCF, BAF, BMF and BSAF values of Profenofos in aquatic trophic

levels.

Trophic Level BCF (μg/kg

lipid)/(μg/L) BAF

(μg/kg

lipid)/(μg/L) BMF

(μg/kg

lipid)/(μg/kg

lipid) BSAF

(μg/kg

lipid)/(μg/kg

OC)
Phytoplankton 162305 155184 N/A 268 Zooplankton 77102 78497 0.51 135

Benthic Invertebrates 80616 83947 1.09 145

Fil ter Feeders 79499 82727 1.07 143

Small Fish 77777 89250 1.10 154

Medium Fish 77777 100201 1.16 173 Large Fish 81233 127714 1.27 220

Table 14. Calculation of EECs for mammals and birds consuming fish contaminated by Profenofos.

W ildlife Species Biological Parameters EECs (pesticide intake) Body Weight (kg) Dry Food

Ingestion Rate (kg

- dry food/kg

bw/day) Wet Food

Ingestion Rate (kg

- wet food/kg

bw/day) Drinking

Water

Intake (L/d) Dose Based

(mg/kg

bw/d) Dietary

Based (ppm)

Mammalian

fog/water shrew 0.02 0.140 0.585 0.003 7.443 12.72

rice rat/star

- nosed

mole 0.1 0.107 0.484 0.011 6.305 13.03

small mink 0.5 0.079 0.293 0.048 5.937 20.24

large mink 1.8 0.062 0.229 0.168 4.639 20.24

small river otter 5.0 0.052 0.191 0.421 3.868 20.24

large river otter 15.0 0.042 0.157 1.133 4.054 25.80Page 60 of 75 Avian
sandpipers 0.0 0.228 1.034 0.004 13.5278 13.08

cranes 6.7 0.030 0.136 0.211 1.8804 13.84

rails 0.1 0.147 0.577 0.010 8.8765 15.37

herons 2.9 0.040 0.157 0.120 2.5941 16.48

small osprey 1.3 0.054 0.199 0.069 4.0364 20.24

white pelican 7.5 0.029 0.107 0.228 2.7528 25.80

Table 15. Calculation of toxicity values for mammals and birds consuming fish contaminated by Profenofos.

Wildlife Species Toxicity Values

Acute Chronic

Dose

Based (mg/kg

bw) Dietary

Based (mg/kg

- diet) Dose Based

(mg/kg

- bw) Dietary

Based (mg/kg

- diet)

Mammalian fog/water shrew 323.51 N/A 0.77 7.3

rice rat/star

- nosed

mole 219.46 N/A 0.52 7.3

smal l mink 144.68 N/A 0.34 7.3

large mink 102.30 N/A 0.24 7.3

small river otter 79.24 N/A 0.19 7.3

large river otter 60.21 N/A 0.14 7.3

Avian
sandpipers 28.56 57.00 N/A 1

cranes 68.31 57.00 N/A 1

rails 34.46 57.00 N/A 1

herons 60.25 57.00 N/A 1

small osprey 53.10 57.00 N/A 1

white pelican 69.47 57.00 N/A 1Page 61 of 75

Table 16. Calculation of RQ values for mammals and birds consuming fish contaminated by Profenofos.

Wildlife Species Acute Chronic

Dose

Based Dietary

Based Dose Based Dietary

Based

Mammalian fog/water shrew 0.023 N/A 9.711 1.742

rice rat/star

- nosed

mole 0.029 N/A 12.127 1.785

small mink 0.041 N/A 17.321 2.773

large mink 0.045 N/A 19.139 2.773

small ri ver otter 0.049 N/A 20.601 2.773

large river otter 0.067 N/A 28.418 3.534

Avian
sandpipers 0.474 0.230 N/A 13.084

cranes 0.028 0.243 N/A 13.836

rails 0.258 0.270 N/A 15.373

herons 0.043 0.289 N/A 16.479

small osprey 0.076 0.355 N/A 20.241

white pelican 0.040 0.453 N/A 25.798Page 62 of 75



### Appendix F. Predictive Data for Parent Profenofos and its Degradates from

QSAR Modeling using ECOSAR v1.11
All values are in ppb ND = No empirical Data NP = No prediction made for this c lass.

Red highlighted cells indicate poor agreement ( i.e. > 10x difference) between empirical data and predicted values.

Yellow highlighted cells indicate reasonable agreement ( i.e. between 5x and 10x difference) between empirical data and predicted valu es. Green highlighted cells indicate good agreement ( i.e. <5x difference) between empirical data and predicted values.

The empirical EC 50 for green algae was from a 72

- hour study (MRID 48612104) and was considered of qualitative use. However, the level o f predicted toxicity using the Esters class had very good agreement with this empirical value while the Esters (phosphate) and Neutral Organic SAR classes had reasonable agreement with the empirical data. Using these three classes, the model predicts the O

- ethyl

- S

- propyl phosphorothioate degradate to be ~3x to ~10x less toxic to green algae than parent profenofos. Using the Neutral Organic SAR class (the only class for which this degradate and parent profenofos share according to the ECOSAR model), the mo del predicts the 4

- bromo

- 2

- chlorophenol degradate to be ~10x less toxic to green algae than parent profenofos which is also similar to the empirical data for this metabolite to the marine green algae. Other degradates were predicted to be >10x less toxic than parent profenofos to this taxa using classes that had reasonable or good predictive power.

Table F1. Empirical and Predicted Green Algae EC 50 Toxicity Estimates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

EC50 (pp b ) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 508 (qualitative) 456 2926 1402 NP

O

- ethyl

- S

- propyl phosphorothioate ND 1560 28,306 4,729 NP

4

- bromo

- 2

- chlorophenol 24,900 (marine green algae,

qua litative) NP NP 13,579 11,493

O

- ethyl phosphate ND >1,000,000 >1,000,000 >1,000,000 NP

1

- propanethiol ND NP NP 38,891

The empirical NOAEC from that same study had good agreement with the Esters chemical class and reasonable agreement wi th the Neutral Organic SAR class

. Using these two classes, the ECOSAR model predicts the O

- ethyl

- S

- propyl phosphorothioate degradate to be ~2.5x

— ~2.8xPage 63 of 75

less toxic than parent profenofos. The 4

- bromo

- 2

- chlorophenol was predicted to be ~6.7x less toxic than parent profen ofos, using the Neutral Organic SAR class. Other degradates were predicted to be >10x less toxic than parent profenofos to this taxa using classes that had reasonable or good predictive power.

Table F2. Empirical and Predicted Green Algae NOAEC Toxicity E stimates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

NOAEC (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 130 (qualitative) 294 3,172 658 NP

O

- ethyl

- S

- prop yl phosphorothioate ND 748 8,963 1,842 NP

4

- bromo

- 2

- chlorophenol 20,750 (marine green alga, qualitative) NP NP 4,411 5,328

O

- ethyl phosphate ND 732,950 >1,000,000 >1,000,000 NP

1

- propanethiol ND NP NP 38,891 NP

The predicted acute toxicity to daphnids of parent profenofos had good agreement with the empirical data only for the Esters (phosphate) class. Using this structural chemical class, the O

ethyl

- S

- propyl phosphorothioate degradate has similar (~1.6x) predicted toxicity as the predicted

parent to xicity. The O

- ethyl

- S

- propyl phosphorothioate would be considered very highly toxic on an acute basis to freshwater aquatic invertebrates according to this predicted toxicity. Other profenofos metabolites were predicted to be >10x less toxic than parent profenofos to this taxa using the Esters (phosphate) class.

Table F3 . Empirical and Predicted Daphnid EC 50 Toxicity Estimates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

EC50 (ppb) Chemical Class for Predicted Estimates of Toxicit y

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 0.91 1,679 1.24 636 NP

O

- ethyl

- S

- propyl phosphorothioate ND 4,976 2.0 3,039 NP

4

- bromo

- 2

- chlorophenol ND NP NP 12,222 2,766Page 64 of 75

O

- ethyl phosphate ND >1,000,000 183 >1,000,000 NP

1

- propaneth iol ND NP NP 57,254 NP

The empirical NOAEC for daphnids does not have good or reasonable agreement with the predicted toxicity for any of the chemical classes predicted by ECOSAR (all classes either predicted toxicity >10x the empirical values or did not have any prediction) . Therefore

, the QSAR approach should not be used in the risk assessment to evaluate the toxicity of profenofos

metabolites to freshwater invertebrates on a chronic basis.

Table F4 . Empirical and Predicted Daphnid NOAEC Toxicity Es timates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

NOAEC (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 0.20 507 NP 129 NP

O

- ethyl

- S

- propyl phosphorothio ate ND 1,953 NP 487 NP

4

- bromo

- 2

- chlorophenol ND NP NP 1,560 525

O

- ethyl phosphate ND >1,000,000 NP >1,000,000 NP

1

- propanethiol ND NP NP 5,247 NP

The empirical acute data for freshwater fish also had poor agreement with the predicted toxicity

for the chemical classes predicted by ECOSAR. Therefore, the QSAR approach should not be used in the risk assessment to evaluate the toxicity of profenofos metabolites to freshwater fish

on an acute basis.

Table F5 . Empirical and Predicted Fish LC 50 Toxicity Es timates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

L C50 (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 14.1 1,095 819 862 NP

O

- ethyl

- S

- propyl phosphorot hioate ND 2,943 1350 4,478 NP

4

- bromo

- 2

- chlorophenol ND NP NP 19,541 5,763

O

- ethyl phosphate ND >1,000,000 74,130 >1,000,000 NP

1

- propanethiol ND NP NP 103,108 NP

However, t he empirical chronic d ata for freshwater fish had good agreement with the pred icted toxicity for the Esters (phosphate) structural class and poor agreement with the other classes.Page 65 of 75

Using the Esters (phosphate) class , the O

- ethyl

- S

- propyl phosphorothioate degradate predicted toxicity is identical to the predicted parent toxicity. The O

- ethyl phosphate metabolite of O

ethyl

- S

- propyl phosphorothioate was predicted to be ~ 2.5x less toxic on a chronic basis than

either the O

- ethyl

- S

- propyl phosphorothioate degradate or parent profenofos. Toxicity was not predicted for 4

- bromo

- 2

- chlorophe nol or other degradates using the Esters (phosphate) class, so predictions cannot be made with any certainty regarding these degradates’ toxicity to fish on a

chronic basis.

Table F6 . Empirical and Predicted Fish NOAEC Toxicity Estimates for Parent Profe nofos and its Degradates. Parent/Degradate Empirical

NOAEC (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 2.0 45 8.0 115 NP

O

- ethyl

- S

- propyl phosphorothioate ND 148 8.0 540 NP

4

- b romo

- 2

- chlorophenol ND NP NP 2,141 678

O

- ethyl phosphate ND 730,747 20 >1,000,000 NP

1

- propanethiol ND NP NP 9,817

The empirical acute data for the mysid had very good agreement with the predicted toxicity for the Esters (phosphate) chemical class. U sing this chemical class, the O

- ethyl

- S

- propyl phosphorothioate degradate is predicted to have similar (1.5x less toxic) toxicity as parent profenofos. According to this predicted toxicity value, this degradate would be considered very highly toxic on an acute basis to saltwater aquatic invertebrates. Toxicity was not predicted for

4

- bromo

- 2

- chlorophenol or 1

- propanethiol using the Esters (phosphate) class, so predictions cannot be made with any certainty regarding this degradate’s toxicity to estuarine/m arine invertebrates on an acute basis. Other profenofos metabolites were predicted to be >10x less toxic than parent profenofos to this taxa on an acute basis.

Table F7 . Empirical and Predicted Mysid L C 50 Toxicity Estimates for Parent Profenofos

and its Degradates. Parent/Degradate Empirical

L C 50 (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic SAR Phenols

Parent 2.4 340 4.0 NP NP

O

- ethyl

- S

- propyl phosphorothioate ND 1,512 6 NP NP

4

- bromo

- 2

- chlorophe nol ND NP NP NP NP

O

- ethyl phosphate ND >1,000,000 74 NP NP

1

- propanethiol ND NP NP NP NPPage 66 of 75

The available empirical data on profenofos’ chronic toxicity to mysids had reasonable agreement with the predicted toxicity using the Esters (phosphate) structura l class. Using this chemical class, the O

- ethyl

- S

- propyl phosphorothioate degradate is predicted to have a similar (~1.6x) chronic endpoint as parent profenofos. The O

- ethyl phosphate metabolite is predicted to be significantly less toxic (>10x) than par ent profenofos using this class. Toxicity was not predicted for 4

- bromo

- 2

- chlorophenol using the Esters (phosphate) class, so predictions cannot be made with any certainty regarding this degradate’s toxicity to estuarine/marine invertebrates

on a chronic basis.

Table F8 . Empirical and Predicted Mysid NOAEC Toxicity Estimates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

NOAEC (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 0.22 77 0.032 NP NP

O

- ethyl

- S

- propyl phosphorothioate ND 2,178 0.053 NP NP

4

- bromo

- 2

- chlorophenol ND NP NP NP NP

O

- ethyl phosphate ND >1,000,000 3 NP NP

1

- propanethiol ND NP NP NP NP

The ECOSAR model poorly predicts toxicity to saltw ater fish on an acute basis compared to the empirical data. Therefore, the QSAR approach should not be used in the risk assessment to evaluate the toxicity of profenofos metabolites to saltwater fish on an acute basis. Although no empirical chronic data are available for saltwater fish, the NOAEC derived using the ACR derived from the acute and chronic fathead minnow data was used as the empirical chronic saltwater value. The ECOSAR model poorly predicts chronic toxicity to saltwater fish when using this value as the empirical chronic endpoint. Therefore, the QSAR approach should not be used in the risk assessment to evaluate the chronic toxicity of profenofos metabolites to saltwater

fish.

Table F9 . Empirical and Predicted Saltwater Fish L C 50 Toxicity Estimates for Parent Profenofos and its Degradates. Parent/Degradate Empirical

LC 50 (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 7.7 1,399 664 NP NP

O

- ethyl

- S

- propyl phosphorothi oate ND 3,978 826 NP NPPage 67 of 75

4

- bromo

- 2

- chlorophenol ND NP NP NP NP

O

- ethyl phosphate ND >1,000,000 7,040 NP NP

1

- propanethiol ND NP NP NP NP

Table F10 . Empirical and Predicted Daphnid EC 50 Toxicity Estimates for Parent Profenofos and its Degradates.

Parent /Degradate Empirical

NOAEC (ppb) Chemical Class for Predicted Estimates of Toxicity

Esters Esters

(phosphate) Neutral

Organic

SAR Phenols

Parent 0.13 (ACR

value) 334 22 NP NP

O

- ethyl

- S

- propyl phosphorothioate ND 807 31 NP NP

4

- bromo

- 2

- chlorophenol ND NP NP NP NP

O

- ethyl phosphate ND 552,296 730 NP NP

1

- propanethiol ND NP NP NP NPPage 68 of 75



### Appendix G. Length of Time for Profenofos Residues to Decrease Below LOCs after Application.Page 69 of 7 5 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0 800.0 900.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assuming 35

- D half

- life)

vs Mammalian Herbivore/Insectivore LOCs (as dietary concentrations

Short Grass Tall Grass Broadleaf plants Fruits/pods/seeds Arthropods Chronic LOC 15 g Mammal Acute LOC 35 g Mammal Acute LOC 1000 g Mammal Acute LOC Time (days)Page 70 of 75 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0 800.0 900.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assuming 35

- D half

- life)

vs Avian LOCs (as dietary concentrations)

Short Grass Tall Grass Broadleaf plants Fruits/pods/seeds Arthropods Avian Acute Non-endangered LOC

Avian Chronic LOC Avian Acute Endangered LOC Time (days)Page 71 of 75 0.0 500.0 1000.0 1500.0 2000.0 2500.0 3000.0 3500.0 4000.0 4500.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assuming 35

- D half

- life)

vs Mammalian Granivore LOCs (as dietary concentrations)

Short Grass Tall Grass Broadleaf plants

Fruits/pods/seeds Arthropods Chronic LOC
15 g Mammal Acute LOC 35 g Mammal Acute LOC 1000 g Mammal Acute LOC
15 g Endangered Mammal Acute LOC 35 g Endangered Mammal Acute LOC 1000 g Endangered Mammal Acute LOC Time (days)Page 72 of 75

0.0 50.0 100.0 150.0 200.0 250.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assuming 0.711

- D half life)

vs Mammalian Herbivore/Insectivore LOCs (as dietary concentrations

Short Grass Tall Grass Broadleaf plants

Fruits/pods/seeds Arthropods Chronic LOC

15 g Mammal Acute LOC 35 g Mammal Acute LOC 1000 g Mammal Acute LOC

15 g Endangered Mammal Acute LOC 35 g Endangered Mammal Acute LOC 1000 g Endangered Mammal Acute LOC Time (days)Page 73 of 75

0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assumes 0.711

- d half life)

vs Avian LOCs (as dietary concentrations)

Short Grass Tall Grass Broadleaf plants Fruits/pods/seeds Arthropods Avian Acute Non-endangered LOC
Avian Chronic LOC Avian Acute Endangered LOC Time (days)Page 74 of 75 0.0 500.0 1000.0 1500.0 2000.0 2500.0

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 Concentration (mg ai/kg dietary item)

Days Terrestrial Residues (upper bound estimates, assuming 0.711

- d half life)

vs Mammalian Granivore LOCs (as dietary concentrations)

Short Grass Tall Grass Broadleaf plants

Fruits/pods/seeds Arthropods Chronic LOC

15 g Mammal Acute LOC 35 g Mammal Acute LOC 1000 g Mammal Acute LOC

15 g Endangered Mammal Acute LOC 35 g Endangered Mammal Acute LOC 1000 g Endangered Mammal Acute LOC Time (days)Page 75 of 75 

### Appendix H. AgDrift Analysis of Spray Drift Effects to Off

- fie ld Organisms.

Profenofos AgDrfit Runs Ground Application at 0.5 lbs a.i./A

Taxa High Boom, VF

Fine Low Boom, VF

fine High Boom, Fine

Coarse Low Boom, Fine

-- Coarse

Daphnid (acute LD50 of 0.91 ppb, therefore
concentrations higher than 0.0455 ppb exceed the listed species LOC) >810 feet >533 >420 >265 Honey bee (LD50 of 0.0953 ug/bee, therefore concentrations higher than 0.03812 μg/bee

exceed the non

- listed species LOC) 90 feet 32 feet 18 feet 10 feet

M allard Duck (LD50 of 55 mg/kg, therefore

concentrat ions above 0.01 lbs/A exceed the listed species LOC.

>125 feet >45 feet >27 feet >15 feet