### 2

preliminary ecological risk hypothesis and analysis plan for evaluating and characterizing
risk to non

- target species in su pport of the registration of PBO.

Many of the environmental fate properties of PBO are known . Based on the available data, it appears that PBO has a moderate tendency to move from soil to surface water, but little tendency to leach to ground water, excep t in coarse

- textured soils. In water, it is slowly metabolized (or rapidly when photolysis occurs) to PBO

- alcohol, PBO

aldehyde and PBO

- acid. In sediment it tends to be stable. It has the potential to
bioaccumulate in terrestrial food chains but little potential to partition from water to air. Exposure should take place mainly in soil and surface water, and from consumption of plants and other food items. Uncertainty exists, however, in the rate at which PBO dissipates on foliage.

PBO is moderately to xic to fish and freshwater invertebrates, and highly toxic to estuarine invertebrates, on an acute basis. Gaps in chronic fish and invertebrate toxic it y data and aquatic plant toxicity data, along with PBO‟s persistence in water, produce
considerable unce rtainties in chronic risk to aquatic organisms. These uncertainties extend to taxa at risk from toxicity of PBO and its major degradates ( PBO

- alcohol, PBO

aldehyde and PBO

- acid) in sediments. Toxicity of PBO‟s major degradates is largely
unknown in both aquatic and terrestrial environments.

PBO is practically non

- toxic to terrestrial animals on an acute basis, although some uncertainty exists because no toxicity data are available for passerine bird species. Since passerines may be more sensitive than m allards or quail, this is an uncertainty. Risk to terrestrial invertebrates is also uncertain. Incident reports confirm that exposure routes exist in which use of products that contain PBO may cause mortality to terrestrial invertebrates. However, the A gency can not attribute incidents to PBO alone since

, as a synergist, it is not intended for use alone, but is always applied with another insecticide
or acaricide . However, the incident data do show that PBO in conjunction with other
insecticides has the potential to adversely affect aquatic species and beneficial insect s

.

PBO is used as a synergist with other pesticides ; therefore , invertebrate toxicity data using a typical end

- use product is needed to adequately characterize risk to terrestrial
inverteb rates. Similarly, typical end

- use product toxicity data is also needed for terrestrial plants to reduce uncertainty and adequately assess risk.

A significant uncertainty for PBO is the nature of the synergistic interactions with other pesticides with whi ch it is mixed and may co

- occur in the environment. In order to evaluate the nature of this synergy, data on the synergistic interaction of each group of pesticide s for which it is intended for co

- application is needed to complete a thorough
assessment. Th is will require the development and review of a large body of data. The Agency recognizes that this data set is extensive and is willing to consider options for a reduced data set that evaluate s the nature of PBO synergy with a limited number of compounds, and allow s bridging to the se more extensive synergy studies from reduced
data sets for other chemicals

. Because the registered uses may result in significant exposure to water bodies

, this data set will be required for fish and invertebrates to
address t he uncertainties associated with PBO‟s synergistic interactions with other pesticides. Section 7.8 and Section 9 provide details regarding the data being requested as part of this problem formulation.

# Environmental Fate and

Ecological Risk Assessment

P roblem Formulation
i n Support of Registration Review for Piperonyl Butoxide

December 13 , 2010



# Environmental Fate and Effects Division Office of Pesticide Programs US Environmental Protection Agency

### 2

Prepared by:
Ibrahim Abdel

- Saheb, Ph.D. Environmenta l Scientist Donna Judkins, Ph.D., Biologist

Secondary Revision: Keith Sappington, Senior Scientist José L. Meléndez, Chemist

Brian Anderson, Chief Jean Holmes, DVM, MPH, Risk Assessment Program Leader
Environmental Risk Branch II

### 3 Table of Contents

1. Purpose

................................ ................................ ................................ .................... 4
2. Problem Formulation

................................ ................................ .............................. 4 2.1. Nature of Regulatory Action

................................ ................................ .................... 4 2.2. Previous Risk Assessments, Scientific Advisory Panels and Background

.............. 5
3. Stressor Source and Distribution

................................ ................................ ............ 8 3.1. Overview of Pesticide Usage

................................ ................................ ................... 9 3.2. Environmental Fate and Transport

................................ ................................ ........ 12
3 .3. Monitoring Data

................................ ................................ ................................ ..... 15 3.4. Open Literature Information

................................ ................................ .................. 15

4. Receptors

................................ ................................ ................................ ............... 15 4.1. Aquatic and Terrestrial Effects

................................ ................................ .............. 16
4.2. Incident Database Review

................................ ................................ ..................... 23 4.3. Ecosystems Potentially at Risk

................................ ................................ .............. 24
5. Assessment Endpoints

................................ ................................ .......................... 24 6. Conceptual Model

................................ ................................ ................................ .. 26
6.1. Risk Hypothesis

................................ ................................ ................................ ... 26 6.2. Conceptual Diagram

................................ ................................ ............................ 27 7. Analysis Plan

................................ ................................ ................................ ......... 31
7.1. Stressors of Concern

................................ ................................ .............................. 32 7.2. Measures of Exposure

................................ ................................ ............................ 32
7.3. Measures of Effect

................................ ................................ ................................ . 34 7.4. Integration of Exposure and Effects

................................ ................................ ...... 35 7.5. Endangered Species Assessments

................................ ................................ .......... 35 7.6. Drinking Wate r Assessment

................................ ................................ .................. 36 7.7. Endocrine Disruptor Screening Program

................................ ............................... 37 7.8. Preliminary Identification of Data Gaps

................................ ................................ 37
8. References

................................ ................................ ................................ ............. 48

9. PRD data request justification tables

................................ ................................ .... 50

### 4

1. Purpose

The purpose of this problem formulation is to provide the foundation for the ecological risk assessment being conducted for the registered uses of piperonyl butoxide, PBO, CAS
Number 51

- 03

- 6. Piperonyl butoxide (PBO) is a pesticide active ingredient that acts as a synergist. 

### Synergists are che micals that enhance the pesticidal properties of other
chemicals. This problem formulation articulates the purpose and objectives of the risk assessment, evaluates the nature of the problem, and provides a plan for analyzing the data and characterizing th e risk (EPA, 1998). Additionally, this problem formulation is intended to identify data gaps, uncertainties and potential assumptions needed to address those uncertainties in characterizing the ecological risk associated with the registered
uses of PBO. PBO is used in combination with a wide variety of insecticides in ratios ranging from 3:1 to 20:1 by weight. It is usually formulated with natural pyrethrins or synthetic pyrethroids and is an ingredient in many registered pest control products. It has numerous and varied commercial and residential applications, is available in a broad range of formulations, and is applied by wide variety of application methods. Commercial uses include pre

- and post

- harvest application to food and non

- food agricultural crops, applications in food and non

- food handling commercial and agricultural structures and outdoor premises, housing for veterinary and farm animals, and direct application to veterinary and farm animals. Additional information on PBO
uses is included i n Section 3.

2. Problem Formulation

2.1. Nature of Regulatory Action

This document serves as the Environmental Fate and Effects Division‟s (EFED) Problem Formulation for the Registration Review of PBO. Previous risk assessments were completed for the uses of the chemical, which serve as the basis for this assessment.

The Food Quality Protection Act of 1996 mandated the Environmental Protection Agency (EPA or the Agency) to implement a new program, i.e ., registration review ( http://www.epa.gov/oppsrrd1/registration_review/ ). All pesticides distributed or sold in the United States generally must be registered by the EPA. The decision to register a pesticide is based on the consideration of sci entific data and other factors showing that it will not cause unreasonable risks to human health, workers, or the environment when used as directed on product labeling. The registration review program is intended to ensure that, as the ability to assess ri sk evolves and as policies and practices change, all registered pesticides continue to meet the statutory standard of no unreasonable adverse effects to human health and the environment. Changes in science, public policy, and pesticide use practices will o ccur over time. Through the new registration review program, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely.

As part of the implementation of the new Registration Review pr ogram pursuant to Section 3(g) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the

### 5

Agency is beginning its evaluation to determine whether PBO continues to meet the FIFRA standard for registration. This problem formulation for the enviro nmental fate and ecological risk assessment chapter in support of the registration review is intended for the initial docket opening the public phase of the review process.

2.2. Previous Risk Assessments, Scientific Advisory Panels and Background

Previous Assessments
The most recent risk assessments and other pertinent documents available in the docket which serve as the basis for this problem formulation include the following:

Reregistration Eligibility Document, RED 1



### . ( D310030) Revised Piperonyl Butoxide RED ( USEPA, 200 6 a 2 

### )

. Response to Comments on Piperonyl Butoxide Risk Assessment (D334539)

, 2007 2009 Scientific Advisory Panel (SAP) on the Evaluation of the Common Mechanism of Action of Pyrethroid Pesticides (EPA

- HQ

- OPP

- 2008

- 0489 3 

### ) EFED Response to Dat a Waivers for Piperonyl Butoxide RED (D334539),
2010

In the 2006 revised RED, levels of concern (LOCs) were exceeded for the following from most of the agricultural uses of Piperonyl Butoxide (PBO) :

acute risk to amphibians, freshwater invertebrates and f reshwater fish; chronic risk to freshwater invertebrates and freshwater fish; and

chronic risk to birds and mammals.

Additionally, for listed species, LOCs were exceeded for: freshwater invertebrates, and amphibians from the mosquito control use; and

mamm als, birds, amphibians, freshwater invertebrates, and freshwater fish from most agricultural uses

.

Risk could not be assessed, due to lack of data, for : chronic risk to estuarine fish and invertebrates;

risk to freshwater fish reproduction; or

risk to non

- target terrestrial plants

.

The following data gaps were identified in 2006 : 132

- 1 Total Foliar Residues ; 72

- 4 Life

- cycle estuarine invertebrate using shrimp;

72

- 5 Full Life Cycle Fish (freshwater); and

122

- 1 Tier I Terrestrial Plant Study.

1 http://www.regulations.gov/s earch/Regs/home.html#documentDetail?R=09000064800b2cf8.

2 http://www.epa.gov/oppsrrd1/reregistration/REDs/piperonyl_red.pdf.

3 http://www.epa.gov/scipoly/sap/meetings/2009/061609meeting.html.

### 6

In the Janua ry 5, 2007 r esponse to comments from the RED (D334539), EPA clarified that PBO had not been categorized as an endocrine disruptor, but would be screened for endocrine disruption potential. In November, 2009, PBO was among a group of
chemicals for which t est orders were issued for Tier I Endochrine Disruptor screening.

OPP presented a “Proposed Common Mechanism Grouping for the Pyrethrins and Synthetic Pyrethroids to a FIFRA SAP in June 2009. OPP proposed two subgroups based on Type I or Type II effects r elated to sodium current tails and neurobehaviorial impact. Information on the SAP follows; further information is also available in the docket (with

non

- copyright material available at http:// www.regulations.gov ) under EPA

- HQ

- OPP

2008

- 0489.

1999 Scientific Advisory Panel 4



### A FIFRA Scientific Advisory Panel (SAP) in 1999 examined the sediment toxicity and fate of synthetic pyrethroids. In response to a question regarding whether sediment toxicity data on one pyret hroid (cypermethrin) could be used to predict sediment toxicity to all pyrethroids, the panel generally supported the method of using data from a few pyrethroids to extrapolate information on toxicity to other pyrethroids. The panel recommended testing cy permethrin, bifenthrin (relatively non

- toxic to freshwater aquatic organisms, very insoluble in water, large bioconcentration factor) and possibly tefluthrin (highly toxic to freshwater aquatic organisms, stable in water, intermediate solubility in

water t o cypermethrin and bifenthrin )

. Although this agreement was made in 1999, the new CFR Part 158 requirements include sediment toxicity tests and these studies are considered particularly important for ecological risk assessment of all synthetic pyrethroids

.

While the biota

- sediment

- accumulation

- factor is a widely accepted method of assessment
of bioaccumulation in sediment organism s, the Panel indicated that the bioconcentration
data for Daphnia and Hyalella should be sufficient to predict bioconcentratio n of pyrethroids. Finally, the Panel indicated that use of a solid phase microextraction (SPME) method to determine the dissolved concentration in water could be used to account for sorption of pyrethroids to organic carbon and colloids present in the wat er column in the measurement of bioconcentration factors.

In 2003 and in response to the comments from the SAP on pyrethroids, EFED requested the following studies on the pyrethroids cyfluthrin, cypermethrin, esfenvalerate and bifenthrin (Rexrode & Melénd ez, memorandum dated 12/22/03):

850.1735: Acute Sediment (freshwater)

- Test organism: Hyalella azteca and Chironomus dilutus

.

- Duration: 10 days, endpoint is survival.

4 http://www.epa.gov/scipoly/sap/meetings/1999/022399_mtg.htm.

### 7

EPA/600/R01/020: Chronic Estuarine/Marine Sediment Testing

- 28 day test on Leptoch eirus plumulosus

.

- Percentage of neonates that survive as adults.

- Growth rate.

- Reproduction (#eggs/ female, etc .).

- Behavior.

A chronic 65

- day freshwater test was also requested only for cypermethrin.

EPA/600/R

- 991064: Chronic Freshwater Sediment T esting

- 65 day test on Chironomus dilutus

.

- Survival.

- Growth rate.

- Reproduction (# eggs/ female, time to oviposition, proportion of females ovipositing, % hatch).

2009 Scientific Advisory Panel OPP presented a “Proposed Common Mechanism Grouping for the Pyrethrins and Synthetic Pyrethroids to a FIFRA SAP in June 2009. OPP proposed two subgroups based on Type I or Type II effects related to sodium current tails and neurobehavioral impact, with esfenvalerate and fenpropathrin showing symptoms of both t ypes. The panel indicated that substances with mixed characteristics could be included in both groups. 5



### 2010 Response to Data Waiver Requests In EFED‟s May 20, 2010 ( D375969, D375962, D375972 )

, Response to Data Waivers for Piperonyl Butoxice RED Case No. 2525 (EPA 738

- 06

- 005) , EFED denied data waivers
for: Guideline 850.1350, Mysid ( Mysidopsis bahia ) Chronic Life

- cycle Study ; Guideline 850.1500

, Fish Life

- cycle Toxicity S tudy; and

Guideline 850.1000, Test method EPA/600/099/064 from Office of Water, an d
OECD 218 and 219

– Chronic Toxicity Sediment Testing to Freshwater Invertebrates and Chronic Toxicity Sediment Testing to Estuarine Invertebrates in
the Sediment Environment

.

Open Literature Information Papers in the open literature indicate concern ove r pyrethroids‟ toxicity towards benthic

and other non

- target aquatic organisms. Open literature will also be evaluated for information on PBO toxicity and prelevance in the environment.

Aquatic Life Criteria and Aquatic Life Benchmarks
The Clean Water Ac t requires the Agency to publish water quality criteria that accurately reflect the latest scientific knowledge on the kind and extent of all identifiable effects on health and welfare which might be expected from the presence of pollutants in any body
of water, including ground water. While these recommended criteria do not, in

5 See Page 18 of the SAP meeting minutes, http://www.epa.gov/scipoly/sap/meetings/2009/061609meeting.html.

### 8

themselves, impose any requirements, states and authorized tribes can use them to develop water quality standards. An Aquatic Life Ambient Water Quality Criteria
document has not be en published for PBO (refer to url: http://www.epa.gov/waterscience/criteria/ ).

Based on toxicity values revised by the EPA, the OPP publishes aquatic life benchmarks for freshwater species, based o n the most sensitive species from the most recent risk assessments. For PBO, no aquatic life benchmarks have been published (see url: http://www.epa.gov/oppe fed1/ecorisk_ders/aquatic_life_benchmark.htm#benchmarks ).

Impaired Water Bodies PBO is not identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Act, based on information provided at http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_grou p_id=885

.

N o Total Maximum Daily Load (TMDL) criteria have been develo ped for PBO, based on information provided at http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutan t_detail?p_pollutant_gr oup_id=885&p_pollutant_group_name=PESTICIDES . More information on impaired
water bodies and TMDLs can be found at http://www.epa.gov/owow/tmdl/ . The Agency invites submission of water q uality data for this pesticide. To the extent possible, data should conform to the quality standards in Appendix A of the OPP Standard Operating Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s Registration Review Risk Ass essment and Management Process (see: http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm ) , in order to ensure they can be used quantitatively or qualitatively in pesticide risk assessments.

3. Stressor Source and Distribution

Piperonyl butoxide is a pesticide active ingredient that acts as a synergist. Synergists are chemicals that enhance the pesticidal properties of other chemicals. Piperonyl butoxide
is intended for use in combination with a wide variety of insecticides and acaricide s in ratios ranging from 3:1 to 20:1 by weight . It is primarily mixed with natural pyrethrins and synthetic pyrethroids.

As a synergist, it inhibits the mixed function oxidase system of insects and reduces the oxidative breakdown of other pesticides.

A summary of physicochemical properties of PBO is included in Table 1

.

### 9

Table 1

. Summary of physicochemical properties of PBO.

PARAMETER VALUE(S) (units) SOURCE

CAS Chemical Name 5

- [[2

- (2

- butoxyethoxy)ethoxy]methyl]

- 6

- propyl

- 1,3

- benzodioxole Factsheet: http://www.alanwood.net/pe sticides/index_cn_frame.ht

ml Chemical Formula C 19 H 30 O 5

IUPAC Chemical Name 5

- [2

- (2

- butoxyethoxy)ethoxymethyl]

- 6

- propyl

- 1,3

- benzod ioxole or 2

- (2

- butoxyethoxy)ethyl 6

- propylpiperonyl ether

PC Code 067501 OPP Databases

Chemical Structure (from chemical’s data sheet)

CAS Reg. No. 51

- 03

- 6 Factsheet: http://www .alanwood.net/pe sticides/index_cn_frame.ht

ml

Molecular Weight 338.45 g/mol 2002 Farm Chemicals
Handbook

Melting Point Liquid at 25 C FOOTPRINT Pesticide Properties Database @ http://sitem.hert s.ac.uk/a eru/footprint/en/

Water Solubility 14.34 μg/mL at 25 °C RD Memorandum, 12/31/90 (cited under D207185)

Solvent Solubility Completely miscible (95% solution) in acetone,

methanol, petroleum distillate, petroleum ether, methylene chloride, and i sooctane MRID 43288601 ( D207185 )

Vapor Pressure (25 o C) 5 x 10 - 13 mmHg @ 25 C (extrapolated from data at higher temperature) MRID 43288601 ( D207185 )

Henry’s Law Constant 1.6 x 10 - 14 atm

- m 3 /mol (calculated as VP/solubility) FOOTPRINT Pesticide Properties Database @ http://sitem.herts.ac.uk/a eru/footprint/en/

Octanol

- Water Partition Coefficient (20 o C) (log K OW ) 4.75 FOOTPRINT Pesticide Properties Database @ http://sitem.herts.ac.uk /aeru/footprint/en/



### Major degradates of concern are PBO

- alcohol, PBO

- aldehyde, and PBO

- acid.

3.1. Overview of Pesticide Usage

Piperonyl butoxide (PBO) currently has 70 tolerances (40 CFR 180.127) in/on vari ous crop and livestock food commodities. Residentially, it is used to control insects inside the home and outside on gardens, lawns and ornamentals, patios, and other outdoor

### 10

structures, and is directly applied to pets. Comprehensive information on use p atterns and formulations is provided in the Piperonyl Butoxide Master Label which was submitted to the EPA by the Piperonyl Butoxide Task Force II. The risk assessments for piperonyl butoxide are based solely on the Master Label, since it only lists the u ses that the Task Force II are supporting. See Table 2 for a summary of uses and Appendix A for a comprehensive list of uses that will be assessed for Registration Review

.

Table 2

. PBO Reg istered Crop Groups and PRZM Scenarios to Represent Them

Crop Group PRZM Scenario

1: Root and Tuber Vegetables (39 crops) 2: Leaves of Root and Tuber Vegetables (18 crops) ID potato, ME potato, FL carrot, CA sugarbeet, MN sugarbeet

4: Leafy Vegetables ( Except Brassica Vegetables) (31) CA lettuce

5: Brassica (cole) Leafy Vegetables (16 crops) FL cabbage

6: Legume Vegetables (succulent or dried) (43 crops) 7: Foliage of Legume Vegetables (7 crops) MI beans, OR snapbeans

8: Fruiting Vegetables (except Cu curbits) (10crops) FL peppers, FL tomato, CA tomato,

PA tomato

9: Cucurbit Vegetables (17 crops) FL cucumber

10: Citrus Fruits (14 crops) CA citrus, FL citrus

13: Berries (9 crops) OR berries

Miscellaneous (3 crops) MS cotton, TX cotton, NC cotton

FL turf, PA turf FL strawberries, CA grapes

Note: Number in parentheses after Crop Group name is number of crops listed on Master Label for that

group.



### Screening level estimate of piperonyl butoxide usage performed by EPA‟s Biological and Economical Analysi s Division (BEAD) indicates that 5,000 to 10,000 pounds of piperonyl butoxide are used annually in the U.S. for application to agricultural crops, with highest usage on potatoes (30% of treated crops) and other uses at 5% or less. An estimated 100,000 to 200,000 pounds are used annually for non

- crop uses.

Some agricultural usage information was obtained from the USDA Regional IPM Centers
website www.ipmcenters.org/datasources/nass/output/NASS.cfm . A copy of the data table is given in Appendix A

. The USDA website reports the use of PBO in some years between 1990 and 2001 in the following states and crops: eggplant (NJ), tomatoes (NJ, MI), and fall potatoes (MI, NY, PA, ME, WI). In California, use was reported on head and “other” lettuce, spinach, cauliflower, and celery. The quantitative reliability of the data could not be assessed; however, the following information was given.

### 11

In California, PBO was used on 1 to 3% of cauliflower (1994) and celery (1994, 1996 ) acres, on 3 to 25% of combined head/other lettuce (even years 1992

- 2000), and 13 to
24% of fresh

- market spinach acres (1992, 1994, 1996).

In New Jersey, PBO was used on eggplant (25 to 26% of acres in 1992, 1994), and on 21
to 25% of fresh

- market tomato acres (1992, 1994). In Michigan, PBO was used on 28%
of tomato acres in 1992.

Potatoes appear to be the most widespread agricultural use of PBO. The use of PBO on fall potatoes in Maine was 4 to 7% of acres (1993

- 4); 45 to 70% of acres in Michigan (199 2

- 4); 22 to 41 % of acres in New York (1992

- 4); 1 to 75% of acres in Pennsylvania (1992

- 5, 1998); and 17 to 33% of acres in Wisconsin (1995, 1997

- 9, 2001).

The highest reported use rates for PBO were in New Jersey on eggplant (average 4.4 to 5.1 applica tions totaling 2.4 to 2.89 lb/acre/year) and on tomatoes (average 3.5 to 5.3 applications totaling 1.89 to 2.47 lb/acre/year). The highest use reported on potatoes was in New York (1994), with an average 2.8 applications totaling 2.24 lb/acre/year. In

Ca lifornia lettuce, the highest reported use rate was 0.58 lb/acre/year from 1 to 2 applications.

Piperonyl butoxide can be applied with aerial or ground equipment . There are many other
use sites for PBO , as shown in the Stressor Source and Distribution sec tion.

Based on private market pesticide usage data from 1998

- 2008, the annual total agricultural usage averaged approximately 97,000 pounds active ingredient for almost 664,000 million acres of all crops ( EPA proprietary data , 1998

- 2008 ). There was no PBO use on alfalfa, except in 2003 (almost 4,500 lbs.), no use on lemons from 1998

- 03, almost 2,000 lbs. in 04 and started to decline from then on, use on lettuce peaked in 05 (almost 4,000 lbs.) and went down to 341 lbs. in 2008, usage on potatoes peaked in 04 (almost 8,500 lbs.) and went down to zero in following years, sorghum/milo was treated only in 2000 (almost 8,000 lbs.), use on strawberries was mainly in 2000 (almost 4,000 lbs.), and almost went down to zero there after, sweet corn was treated by piperonyl

butoxide in 2000 only (almost 4,000 lbs.), and winter wheat was mainly treated in 2007 (almost 38,000 lbs.).

During the same time period, 1998

- 2008, the largest markets in terms of total pounds of active ingredient applied were: winter wheat (3 9 %), potatoes ( 13 %), milo sorghum ( 8 %),
lettuce ( 6 %), alfalfa, strawberries, & lemons ( 5 % , each ) , and sweet corn (4%) ( GfK Kynectec, 1998

- 2008, Figure 1 ).

### 12

Figure 1

. Estimated Use of PBO

3.2. Environmental Fate and Transport

A summary of environmental fate/ transport properties from Subdivision N guideline
studies for PBO is presented in Table 3

. Aquatic modeling inputs will be generated using d ata included in Table 3 using the most current guideance on input selection.

Table 3

. Summary of environmental fate and transport properties of PBO.

Guideline Test Value or Result Reference/ Comment



### Hydrolysis Stable MRID 435956 01

Aqueous Photolysis Parent half

- life 8.4 hours at

25 C and pH 7
Total Toxic Residues ( TTR;
PBO

- alcohol, PBO

- aldehyde,
and PBO

- acid) half

- life 5.7 days MRID 436372

- 01
as amended 5/17/2004

Soil Photolysis Result uncertain due to rapid degradation of dark control MRID 43720801

Aerobic Soil Metabolism Parent half

- life 14 days in sandy loam soil
TTR half

- life 24 days MRID 43806401
as amended 5/17/2004

Anaerobic Aquatic
Metabolism Stable for 181days in flooded sandy loam soil

- water system
at 25 C MRID 43836501

Aerobic Aquatic
Metabolism Parent half

- life 75 day s TTR half

- life 133 days MRID 43803401

as amended 5/17/2004

### 13

Guideline Test Value or Result Reference/ Comment



### Adsorption

- Desorption (Batch Equilibrium) Adsorption Koc range 399

- 830 mL/g Desorption Koc range 390

- 1152 mL/g MRID 43673801
43673802

Adsorption

- Desorption (Column Leaching) Unaged soil Colu mn: Parent PBO leached only in sand

soil 43673801
43673802

Hydroxyl Radical
Reaction half

- life 0.1 day (estimated by EPI

Suite)

Accumulation in Fish
Tissue 260x, 91x, and 380x for

whole fish, edible tissue, and nonedible tissue (MRIDs
42404401 and 42538 803) MRID 42404401
42538803

Taken together, these data indicate that PBO will have a moderate tendency to move from soil to surface water, and little tendency to leach to ground water except in coarse

textured soils.

Degradation and Metabolism

In wate r bodies, PBO will be slowly metabolized (75

- day half

- life), or in shallow, clear waters, rapdily degraded by photolysis to PBO

- alcohol, PBO

- aldehyde, and PBO

- acid (see Appendix B for structures). PBO reaching anaerobic sediments will tend to be
stable an d available for desorption to the water column.

Soil Sorption and Mobility/Field Dissipation In soil, PBO metabolism appears to be relatively quick (parent half

- life 14 days in one soil tested). PBO

- acid is the main degradate formed in soil (17% at 30 da ys). While parent PBO is not expected to leach

, except in coarse soil, PBO

- acid is expected to be more soluble (2000 ppm or more) and, therefore, more mobile and subject to leaching.

Bioaccumulation
A flow

- through fish bioaccumulation study in bluegill s unfish produced bioaccumulation factors of 260x, 91x, and 380x for whole fish, edible tissue, and nonedible tissue, respectively (MRIDs 42404401 and 42538803). These data suggest that bioaccumulation in fish is not a primary concern.

Transport
PBO will h ave very little tendency to partition from water to the atmosphere. If present in the air as a vapor or spray drift

, it is expected to react rapidly with hydro x yl radicals. The major degradates PBO

- alcohol, PBO

- aldehyde, and PBO

- acid are expected to have less tendency to partition from water to air, due to their much higher expected solubility
in water.

### 14

Exposure to PBO from agricultural use will therefore take place mainly in soil and surface water, and from consumption of plants and other food items ont o which it is sprayed. It may also reach the aquatic environment by passing through wastewater treatment plants and being discharged.

Uncertainties

Several areas of uncertainty exist at this time for assessing PBO, including: The dissipation rate for fo liar residues is uncertain. Field dissipation rates are uncertain. Aerobic metabolism in soil, and both aerobic and anaerobic metabolism in water. Absorption/desorption potential. Aquatic exposure is not currently quantifiable for the exposure route involv ing PBO or major degradates (PBO

- alcohol, PBO

- aldehyde, and PBO

- acid) passing through municipal wastewater treatment plants and being discharged into an aquatic receiving

stream. Comparative toxicity of degradates is not well known. Assuming that degradat es and parent are equally toxic may over

- or under

- estimate toxicity.

F ield incidents reported under section 6(a)(2) indicate that PBO with pyrethrin or pyrethroid insecticides may cause plant mortality. Since this is an area of great uncertainty due to l ack of data, Tier I terrestrial plant studies are needed to decrease this uncertainty. Since passerine birds may be more sensitive to pesticides than mallards or quail

, this is considered an uncertainty. Incident reports confirm that exposure routes exist in which products containing PBO may cause mortality to terrestrial invertebrates. Data is unavailable to quantify effects of a typical end

- use product on terrestrial invertebrates. Gaps in chronic fish and aquatic invertebrate toxicy data and aquatic pla nt toxicity data, along with PBO‟s persistence in water, produce considerable uncertainties in chronic risk to aquatic organisms, from both water column and sediment exposure. A significant uncertainty for PBO is the nature of the synergistic interaction s with other pesticides with which it is mixed, and may co

- occur in the environment. In order to evaluate the nature of this synergy, data on the synergistic interaction of each
of these pesticide s is needed to complete an accurate risk assessment

. Becaus e the registered uses may result in significant exposure to water bodies this data will be required for fish and invertebrates to address the uncertainties associated with PBO‟s synergistic interactions with other pesticide (see section 9 for details ).

Lab els under which PBO is currently sold do not always specify the pesticides or mixing ratios, leaving the mixtures virtually undefinable. This labeling issue results in significant uncertainty and should be addressed in registration review.

Studies are being requested to address each of these uncertainties. In the absence of data, risk will be presumed to exceed concern levels and effectiveness of potential mitigation options may not be possible

.

### 15 3.3. Monitoring Data

The USGS NAWQA and the USEPA " Pesticides in Ground Water Database a compilation of Monitoring Studies: 1971

- 1991 "databases were searched, and no monitoring data on the concentration of Piperonyl butoxide in surface water or groundwater were found at the present time. Piperonyl butoxi de was not included in the The USGS NAWQA (1991

- 2001) list of analytes. However, the Agency is aware of limited monitoring data that demonstrates environmental co

- occurrence of PBO and pyrethroids can occur, though the spatial and temporal extent to which this occurs is not clear (Weston et al, 2006; Amweg et al, 2006)."

3.4. Open Literature Information

The open literature contains many valuable studies on the toxicity of PBO and its influence on the toxicity of other pesticides; see the revised RED ( 2006 a ) for a review of PBO‟s synergistic and antagonistic effects to other pesticides. The presence of PBO in a water body was found to either increase or decrease the toxicity of a mixture of insecticides, depending on which ones were present. PBO increased the toxicity of pyrethroids/pyrethrins, decreased the toxicity of OP insecticides that require metabolic activation, and had no effect on OP insecticides that did not require activation . A literature search will be conducted using the Ecotox database, and relevant open literature
will be evaluated when the risk assessment is completed.

4. Receptors

Consistent with the process described in the Overview Document 6 

### , the risk assessment for PBO will rely on a surrogate species approach. T oxicological data generated from surrogate test species, that are intended to be representative of broad taxonomic groups, are used to extrapolate to potential effects on a variety of species (receptors) included under these taxonomic groupings.

A cute and chronic toxicity data from studies submitted by pesticide registrants along with the available open literature are used to evaluate the potential direct and indirect effects
of PBO on aquatic and terrestrial receptors. Toxicity studies for the techni cal grade active ingredient (TGAI) and the typical end

- use product (TEP) will all be considered in the ecological risk assessment. O pen literature studies are identified using EPA‟s

ECOTOX database 7 

### that employs a literature search engine for locating che mical toxicity data for aquatic life, terrestrial plants, and wildlife. R esearch papers accepted into the ECOTOX database are screened using standard procedures to ensure consistent, high quality information; these studies will be considered during the „A nalysis‟ phase of risk assessment process. The Ecological Incident Information System (EIIS, version 2.1 8 

### ) that tracks incident reports submitted to EPA and the Avian Monitoring Information

6 Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs. Office of Prevention, Pesticides, and Toxic Substances. Off ice of Pesticide Programs. Washington, D.C. January 23, 2004.

7 http://www.epa.gov/ecotox

8 http://www.epa.gov/oppefed1/general/databasesde scription.htm

### 16

System (AIMS 9 

### ) will be used to identify supportive, line of evide nce information on exposure of aquatic and terrestrial receptors. Data from all of these sources can also provide insight into the direct and indirect effects of PBO on biotic communities from loss of species that are sensitive to the chemical and from ch anges in structure and
functional characteristics of the affected communities.

4.1. Aquatic and Terrestrial Effects

Effects on Aquatic Organisms

A cute aquatic toxicity data are available for PBO; however, chronic toxicity data are incomplete, lacking a f

ish life cycle study, estuarine/marine chronic studies, sediment toxicity studies, as well as aquatic plant studies. Table 4 provides a summary of the most sensitive data from taxonomic groups and the surrogate sp ecies used to characterize potential acute and chronic aquatic effects of PBO. A list of all submitted studies to date
is found in Appendix C

.

Table 4

. Aquatic toxicity profile for PBO

Taxon Exposure

Duration Guideline Most
Sen sitive Species

Tested Toxicity

Value Acute

Toxicity Category 1 Classi

fication Data Gap

Yes/No MRID

Freshwater
Fish Acute 850.1075 Rainbow trout Oncorhynchus mykiss LC 50 = 1.9

m g/L using TGAI, no
data for

TEP

, synergistic
data Moderately

Toxic Acceptable

- - No

Yes for

TEP

, degradates
and synergistic
data 42540303

--

Chronic 850.1400

850.1500 Fathead

minnow Pimephales promelas NOAEC =

0.04 mg

a .i./ L
LOAEC = 0.11 mg
a.i./ L 2

Missing
Data for
Fish LC 3

test NA ELS 3 test, Acceptable

Unfulfilled

D CI 5 for LC

test

, w aiver
request denied (DP
3759 7 2 ) Yes 6

for LC study 43300301

--

Estuarine/
Marine Fish Acute 850.1075 Sheepshead
minnow Cyprinodon variegatus LC 50 =

3.94 mg a.i./ L Moderately

Toxic Acceptable No 42540304

Chronic 850.1400

-- 7 No Data

-- -- Yes 6

--

Freshwater
Invertebrates Acute 850.1010 Waterflea Daphnia

magna LC 50 =

0.51 mg
a.i./L using TGAI, no
data for

TEP synergistic
data

, Highly

Toxic Acceptable

-- No

Yes, for

TE P

, synergistic data, 42540301

--

9 American Bird Conservency database, http://www.abcbirds.org/

.

### 17 Taxon Exposure

Duration Guideline Most
Sen sitive Species

Tested Toxicity

Value Acute

Toxicity Category 1 Classi

fication Data Gap

Yes/No MRID

Chronic 850.1300 Waterf lea D.

magna NOAEC =

0.03 mg
a.i./L

LOAEC = 0.047 mg
a.i./L 8 NA Acceptable No 43311301

SS850.1000 Invertebrate

Sediment Test No Data

-- Unfulfilled DCI, w aiver
request denied (DP
37596 9 ) Yes 6

--

Estuarine/
Marine
Invertebrates Acute Mysid shrimp Mysid opsis
bahia

Eastern Oyster

Crassostrea virginica LC 50 =

0.49 mg
a.i./ L

LC 50 = 0.23 mg
a.i./ L Highly

Toxic Acceptable

Supplemental, Qualitative No 43901801

42540305

Chronic 850.1350

-- No Data

-- Unfulfilled DCI, w aiver
request denied (DP
37596 2) Yes 6

--

SS850.1000 Invertebrate

Sediment Test No Data

-- Unfulfilled DCI, w aiver
request denied (DP
37596 9 ) Yes 6

--

Amphibians Acute No
Guideline Western

chorus frog tadpole
Pseudacris

triseriata LC 50 =

0.210 mg a.i./ L Highly

Toxic Supplemental No 40098001

Non

vascular plant Tier I and

Tier II 9 850.5400

-- No Data

-- Unfulfilled

DCI Yes 6 for

TEP --

Vascular plant Tier I and

Tier II 9 850.4400

-- No Data

-- Unfulfilled
DCI Yes 6

--

1 Categories of acute toxicity for aquatic organisms based on LC 50 (mg/L): < 0.1 very highly toxic; 0.1

- 1 highly toxic; >1

- 10 moderately toxic; >10

- 100 slightly toxic; >100 practically nontoxic.

2 Based on embryo survival at hatch, and length and weight of larvae

. 3 ELS = early life

- stage.

4 DCI = data call

- in

5 LC = lif e cycle.

6 DCIs have been issued for these studies but data has not been submitted; therefore, a data gap still exists.

7 Missing Data.

8 Based on reproductive effects.

9 If exceed 50% effect in Tier I, also need Tier II.



### A significant uncertainty for PBO is the nature of the synergistic interactions with other pesticides with which it is mixed, and may co

- occur in the environment. In order to evaluate the nature of this synergy, data on the synergistic interaction of each group of pesticide s for which it is intended for co

- application is needed to complete a risk

### 18

assessment. This will require the development and review of a large body of data. The Agency recognizes that this data set is extensive and is willing to consider options for a
reduced data se t that evaluates the nature of PBO synergy with a limited number of compounds, and allows bridging to these more extensive synergy studies from reduced
data sets for other chemicals. Some submitted studies exist that look at the toxicity of a single PBO + pyrethrins product (60% PBO and 6% pyrethrins) on both freshwater and
estuarine/marine inverts & fish ( Table 27b on page 64 of the pyrethri ns RED, USEPA,
2006 b ).

Freshwater Fish and Aquatic

- Phase Amphibians PBO is moderately toxic to freshwater fish and aquatic

- phase amphibians on an acute basis (LC 50 

### = 1.9 ppm , MRID 42540303 ). A no

- observed adverse effect concentration (NOAEC) of 0.04 ppm was estimated from a chronic early life stage study with fathead minnows in which embryo survival at hatch, and leng th and weight of larvae, were
observed at the lowest

- observed adverse effect concentration (LOAEC) of 0.11 ppm (MRID 43300301)

. Because PBO can be directly applied to water, EPA needs toxicity data on the typical end

- use product (TEP) and major degradates (which have similar structures and, therefore, are expected to have similar toxicological properties ) to
characterize the risks to fish and aquatic

- phase amphibians

. The data set described above to address uncertainties associated with PBO‟s synergistic interactions with other pesticides would satisfy the TEP requirement (see Section 9).

PBO and its major degradates are persistent, mobile and may pass through wastewater
treatment processes. Since the expected peak EECs ( 58 to 160 ppb, for aerial app lication to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 10 

### ) exceed 0.1 of the NOAEC from the early

- life stage study of 40 ug/L (40ppb*0.1 = 4 ppb, MRID 42540304), a fish life

- cyc le

test is required

. This requirement is based on PBO use in a variety of products applied directly to water and used in agriculture

. This study was requested as part of the RED and
remains unfulfilled.

Freshwater I

nvertebrates PBO is moderately (daph nid LC 50 

### = 12.0 ppm) toxic to freshwater invertebrates, on an acute basis. An NOAEC of 0.030 ppm was determined from a chronic life cycle study
where Daphnia magna exhibited reproduction affects at the LOAEC (0.047 ppm).

Because PBO can be directly applie d to water, EPA needs toxicity data on the TEP to characterize the risks to invertebrates

. T he data set described above to address uncertainties associated with PBO‟s synergistic interactions with other pesticides would satisfy the TEP requirement.

10 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 19

Est uarine /Marine F ish PBO is moderately toxic (LC 50 

### = 3.94 ppm) to estuarine/marine fish based on observed effects to sheepshead minnow from acute exposure to PBO. There are no chronic data
available for estuarine fish

. An early life

- stage study on sheepsh ead minnows is also required due to the potential for direct application of PBO to saltwater.

Estuarine/Marine I

nvertebrates PBO is highly toxic to estuarine invertebrates (LC 50 

### = 0.49 ppm for mysid, MRID
43901801 and 0.23 ppm for oysters, MRID 4254030 5 ). Chronic toxicity data are required per 40 CFR Part 158.630 due to the potential for direct application of PBO to the estuarine/marine environment, acute toxicity value that is <1 ppm (0.23 for the oyster),
and the expected peak EECs (58 to 160 ppb, f or aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 11 

### ) exceed 0. 0 1 of the acute toxicity values (this would be 4.9 ppb for mysid and 2.3 ppb for oysters). There are no chronic data available for estuarine/marine
invertebrates . Chronic studies were requested in the RED, but no data have been submitted to date. Therefore, this guideline requirement remains unfulfilled.

Whole Sediment Survival, Growth, and Repr oduction Studies
The 1999 SAP 4 

### called for sediment toxicity testing for pyrethroids (see Section 1.0 for more details); afterward , the new CFR Part 158 requirements include d sediment toxicity

tests . T hese studies are considered particularly important for ecological risk assessment of all synthetic pyrethroids and synergists such as PBO.

The new data requirements include chronic sediment toxicity studies for freshwater and marine organisms. According to 40 CFR Part 158, the following conditions can tri gger the need for chronic sediment toxicity studies:
A. If the half

- life of the pesticide in the sediment is ≥ 10 days in either the aerobic soil or aquatic metabolism studies, and
B. If any of the following conditions exist:

1. The soil partition coeffi cient (K d 

### ) is ≥ 50.

2. The log K OW 

### is ≥ 3.

3. The K OC 

### is ≥ 1000

, a nd

, C

. If the estimated environmental concentration (EEC) in sediment is > 0.1 of
the acute LC 50 

### /EC 50 

### values.

PBO and its major degradates are persistent, mobile and may pass through waste water treatment processes. PBO has a half

- life of 14d in aerobic soil and 75d in aerobic water (MRIDs 43806401 and 43803401 both as amended 5/17/2004 ), a log Kow of 4.75 and Koc of up to1152 (MRID 43673802, also see Table 3 )

. E xpected peak EECs (58 to 1 60 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 12 

### ) exceed 0.1 of the

acute LC/EC 50 

### (490*0.1 = 49 ppb for M. bahia

, MRID 43901801)

. The criteria are

,

11 P iperonyl B utoxide: Environmental Risk Assessm ent , Revised September, 2005. D139408.

12 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 20

therefore, met for requiring chronic sediment toxicity studies. The required studies
include w hole s ediment s urvival, g rowth, and r eproduction s tudies with Chironomus

tentans

, Leptocheirus plumulosus

, and Hyalella azteca (USEPA, 2000 ) . Test protocols should be submitted before beginning the stud y

. This is a data gap. In the absence of data, EPA will have to presume risk to sediment dwelling freshwater and marine organism.

Amphibians PBO is highly toxic to aquatic

- phase amphibian s on an acute basis (LC50 = 0.21 ppm). No approved guidelines for amphibian acute toxicity testing exist at this time. Available data will be used to assess the risk to amphibians; often fish are used as a surrogate for aquatic

- phase amphibians , and bird s are typically used as a surrogate for terrestrial

- phase amphibians and reptiles.

.

Aquatic Plants

No data are available to evaluate PBO risk to aquatic plants . Aquatic plant studie were requested as part of the RED; however, no studies have been submitt ed to date. Therefore, this guideline requirement remains unfulfilled.

Effects on Terrestrial Organisms

Laboratory and field toxicity studies are available for characterization of the effects of

PBO to birds (also surrogate for terrestrial

- phase amphibia ns and reptiles) and mammals. For terrestrial invertebrates data is available for toxicity of TGAI, but not TEP. No plant
data is available. Table 5 provides a summary of the most sensitive species tested for

ea ch terrestrial taxonomic group; see Appendix C for a complete list of submitted studies
to date.

Table 5

. Terrestrial toxicity profile for PBO

Taxon Exposure

Duration Most

Sensitive Species

Tested Guidelin

e Toxicity

Value Ac ute

Toxicity Category Classi

fication Data

Gap

Yes/
No MRID

Mammals Acute Rat

Rattus norvegicus 850.2400 LD 50 = 4570 mg ai/kg bw Practically

Non

- toxic -- No 41969001

Chronic Rat

R. norvegicus 850.2400 NOAEC = 1000 ppm (89 mg/Kg/d)
LOAEC =
5 000 ppm (469 mg/Kg/d) 1 NA

-- No 00161118

### 21 Taxon Exposure

Duration Most

Sensitive Species

Tested Guidelin

e Toxicity

Value Ac ute

Toxicity Category Classi

fication Data

Gap

Yes/
No MRID

Birds Acute Oral Bobwhite quail
Colinus virginianus

Passerine 850.2100 LD 50 = >2250 mg ai /Kg bw

No Data Practically

Non

- toxic Accept

able

-- 2 No

Yes 41969008

--

Sub

- acute Dietary Bobwhite

quail

Colinus

vi rginianus

and

Mallard duck

Anas platyrhynchos 850.2200 LD 50 = >5620 mg ai/kg
NO A EC =
1000 mg ai/kg 3 Practically

Non

- toxic Accept

able

Accept

able No 41969006

4196900 7

Chronic Reproduction Bobwhite

quail

Colinus virginianus

and

Mallard duc k

Anas platyrhynchos 850.2300 NOAEC =
300 mg ai/kg

LOAEC =

1 5 00 mg ai/kg 4

NOAEC =

300 mg ai/kg
LOAEC =
1200 mg ai/kg 5 NA Accept

able No 43876301

Terrestrial

Inverte

brates Acute Honey Bee Apis mellifera with TGAI

with TEP 6 850.3020 LD 50 = >25

μg a.i. /b ee, NOAEC = 25 μg
a.i. /bee 7

No Data Practically

Non

- toxic Accept

able

-- No

Yes 41969009

--

Terrestrial
Plants Tier I and

Tier II 8 Seedling

Emergence
and Vegetative Vigor using

TEP 850.4100

850.4150 No Data

-- Unfulfil
led DCI Yes 9

--

1 Based on decreased weight gain in both adults and pups.

2 All pesticides with exposure routes that include consumption by passerine species must be using guideline 850.2100; this is a new data requirement

. 3 Based on mortality and toxicosis.

4,5 Based on number of viable embryos, eggs laid, eggs per female and other parameters tested, including eggshell thickness.

6 TEP = typical end

- use product.

7 Based on mortality.

8 If exceed 25% effect in Tier I test, also need Tier II.

9 A DCI has been submitted for these da ta but no data has been submitted to date; therefore, the data gap remains.



### Acute toxicity to terrestrial animals is categorized using the classification system shown

in Table 6 (U.S. EPA, 2004). Toxicity categories for terrestrial plants have not been
defined.

### 22

Table 6

. Categories of Acute Toxicity for Avian and Mammalian Studies

Toxicity Category Oral LD 50 Dietary LC 50 Very highly toxic < 10 mg/kg < 50 ppm
Highly toxic 10

- 50 mg/kg 50

- 500 ppm
Moderately toxic 51

- 500 m g/kg 501

- 1000 ppm
Slightly toxic 501

- 2000 mg/kg 1001

- 5000 ppm
Practically non

- toxic > 2000 mg/kg > 5000 ppm



### Mammals, Birds, Terrestrial

- Phase Amphibians and Reptiles
PBO is categorized as practically non

- toxic toxic to birds, mammals, terrestrial

- phase amphibians and reptiles, based on mammal and bird acute oral tests (LD 50 

### = 4570 and >2250 mg a.i./Kg, respectively; MRIDs 41969001 and 41969008 ). Acceptable acute avian oral toxicity data are not currently available for a passerine species, which i s now required under the 40 CFR Part 158 (CFR 40 2008) data requirements for conventional pesticides. This guideline requirement is a data gap.

Sub

- acute and chronic studies, available for birds show PBO t o be practically non

- toxic
via the dietary route on an acute basis ( both quail and mallard LC 50 

### = >5620 ppm; MRID s 41969006 and 41969007 ); how ever, PBO reduced the number of viable embryos

, eggs laid, eggs per female and other parameters tested, including eggshell thickness ( mallard NOAEC = 300 ppm; MRID 43876301 ) at 1200 ppm. Studies conducted on laboratory rats were substituted in lieu of wild mammal testing prior to the RED. In a rat developmental study (MRID 00161118 ) the NOAEC was 89 mg/kg/day (1000 ppm) based on decreased body weight gain in both adults and pups.

Terrestrial Invertebrates Terrestrial invertebrate toxicity data are required to quantitatively assess the potential impacts on this group of organisms. Data are needed from the honey bee acute contact study due to wide spread use an d possible drift to off site vegetation in bloom. A honey bee acute contact study (GLN 850.3020; MRID 41969009) shows PBO to be practically non

- toxic to honey bees (LD 50 

### > 25 μ g/bee)

. For honeybees, a pesticide is considered highly toxic if the LD 50 

### is < 2 μg a.i./bee

, moderately toxic if 2

- 11 μg a.i./bee and practically non

- toxic if >11 μg a.i./bee

. Since PBO acts as a synergist, the effects of a typical end

- use product may be much greater. Therefore, studies using the TEP are required and are considered a data gap. Without TEP data, EPA would presume
that risk to terrestrial invertebrates exceeds LOCs.

Terrestrial Plants (Guideline 850.4100 and 850.4150) using the TEP Toxicity data for terrestrial plants are not available. Based on the 40 CFR Part 15 8 data requirements, Tier I level non

- target terrestrial plant data are required for pesticides with a terrestrial, forestry, or residential outdoor use patterns . Therefore, this data gap must be
filled and non

- target terrestrial plant data are required. In the absence of Tier I data,
EFED will use data available from the open literature or will pre sume risk to terrestrial
monocots and dicots (and to organisms that depend on them for survival, growth, or

### 23

reproduction) if no data are available. Results fr om Tier I tests may necessitate the performance of a Tier II test. If a tested terrestrial species exhibits a 25 percent or greater detrimental effect in a Tier I study, a Tier II study is required. If the registrant chooses to only submit a Tier II stud y, a Tier I study will not be required.

The TEP tested should be a representative end

- use product. The proposed rule establishing use of the TEP for vegetative vigor and seedling emergence studies states, “The TEP that contains the highest percentage of active ingredient, and/or is the most commonly used, would be required ” (FR Vol. 70 No. 47; March 11, 2005; 12289).

4.2. Incident Database Review

A n incident review was made on August 31 , 2010 by querrying the Ecological Incident Information System (E IIS, version 2.1) and the Avian Montoring Information System (AIMS ), for more information, see Receptors section, above. R eported ecological
incidents associated with the use of PBO are summarized in Ta ble 7

.

Ta ble 7 . Summary of Reported Incidents Involving PBO

Taxon Number of Incidents Involving PBO

Registered Use/Misuse, (Undetermined) Likelihood,

Highly

Probable Likelihood,

Possible Likelihood, Not

Likely

Terrestrial
Vertebrates 0/0 (1)

- 0

- 1

- 0

-

Terrestrial
Invertebrates 1/0 (2)

- 0

- 3

- 0

-

Terrestrial
Plants 5/0 (2)

- 0

- 7

- 0

- Aquatic
Animals 1/1 (1)

- 0

- 3

- 0

-

Fourteen incidents were found, two additional beyond those described in the RED; both occurred in 2005. In Florida (I016 728

- 007), 12 to 24 butterflies were killed probably by spray drift from mosquito control using Biomist 31 + 66 ULV. In North Dakota (I016634

- 001) the death of 4 Koi carp was possibly (but unlikely) linked to use of Anvil

10+10 ULV . In both of these incid ents, proper use was not determined.

In the incidents reviewed in the RED, as well as the two new incidents, EFED could not attribute any of the incidents to PBO alone since

, as an insecticide synergist, it is never
used alone but always with another ins ecticide. Seven incidents were from registered use of PBO, one from misuse, and six undetermined. The aquatic incident (flounder, flukes, shrimp and crabs) involved resmethrin with PBO; the terrestrial animal incidents involved permethrin with PBO (monar ch butterflies and bees) and rotenone with PBO (swans and geese); the terrestrial plant incidents (mostly ornamental plants) involved permethrin or pyrethrin with PBO. Therefore , the incidents do show that PBO in

### 24

conjunction with an insecticide has the po tential to cause adverse effects to aquatic ecosystems and beneficial insect populations.

4.3. Ecosystems Potentially at Risk

PBO may be applied on a variety of food crops, including (but not limited to) tuber and bulb vegetables, leafy vegetables, leg umes, fruits, cucurbits, nuts, cereals, herbs, spices and miscellaneous commodities. In addition, it may be used in numerous animal food uses including forage, fodder, straw, cereals, grass, hay, ornamentals, foliage and lawn plants, and non

- growing crop uses such as food and feed storage areas and postharvest application. It is applied to animals and their housing, both indoor (including down

- the

drain uses such as shampoos) and outdoor, including corrals and other handling areas, rights

- of

- way, fallow l ands, pastures, rangelands, irrigation systems and flooded areas (for mosquito abatement). It is also used in human food prep and eating areas, and on transportation equipment, including airplanes, boats, buses, boxcars and various transportation containe rs. Thus, the ecosystems at risk may be extensive in scope, and as a result it may not be possible to identify specific ecosystems during the development of a baseline risk assessment. In general terms, terrestrial ecosystems potentially at risk due

to t he use of PBO, could include the treated field and areas immediately adjacent to the treated field that may receive drift or runoff. Areas adjacent to the treated field could include cultivated fields, fencerows and hedgerows, meadows, fallow fields or

gr asslands, woodlands, riparian habitats and other uncultivated areas. Due to the persistence of PBO, it is expected to drift and/or runoff due to application to food crops, resulting in possible exposure to aquatic ecosystems. Aquatic ecosystems potentiall y at risk due to the use of PBO include water bodies adjacent to, or down stream from, the treated field and might include impounded bodies such as ponds, lakes and reservoirs, or flowing waterways such as streams or rivers. For uses in coastal areas, aqua tic habitat also includes marine ecosystems, including estuaries. For mosquito abatement, it may be directly applied to waterbodies during flooding or for irrigation. Since it is used in shampoos and other animal products, it may go down the drain and r each wastewater treatment plants.

5. Assessment Endpoints

Assessment endpoints are defined as “explicit expressions of the actual environmental value that is to be protected.” Defining an assessment endp oint involves two steps: 1) identifying the valued attributes of the environment that are considered to be at risk; and 2) operationally defining the assessment endpoint in terms of an ecological entity (i.e., a community of fish , aquatic

- phase amphibians and aquatic invertebrates) and its attributes (i.e., survival and reproduction). Therefore, selection of the assessment endpoints is based on valued entities (i.e., ecological receptors), the ecosystems potentially at risk, the migration pathways of pesti cides, and the routes by which ecological receptors are exposed to pesticide

- related contamination. The selection of clearly defined assessment endpoints is important because they provide direction and boundaries in the risk assessment for addressing risk management issues of concern. Changes to assessment endpoints are typically estimated from the available toxicity studies, which are used as

### 25

the measures of effects to characterize potential ecological risks associated with exposure to a pesticide, such as PBO.

In its ecological risk assessments, the Agency does not routinely include an evaluation of mixtures of active ingredients, either those mixtures of multiple active ingredients in product formulations or those in the applicator‟s tank. In the case of the product formulations of active ingredients (that is, a registered product containing more than one active ingredient), each active ingredient is subject to an individual risk assessment for regulatory decision regarding the active ingredient on a p articular use site. If effects data are available for a formulated product containing more than one active ingredient, the data may be used qualitatively or quantitatively in accordance with the Agency‟s
Overview Document and the Services‟ Evaluation Memo randum (USEPA, 2004;
Williams an d Hogarth, 2004)

.

In this case a vailable toxicity data for environmental mixtures of PBO with other pesticides will be presented as part of the ecological risk assessment. Because PBO is a pesticide synergist, it is only used in combination with oth er pesticides to enhance their effectiveness (toxicity) to target organisms. Therefore, assessing potential ecological risks of PBO requires evaluating potential exposure and toxicity of the active ingredient (PBO alone) and evaluating the enhanced toxici ty of other pesticides with which it is simultaneously applied. Data are being requested as part of this problem formulation to allow for an assessment of the enhanced toxicity to aquatic organisms resulting form enhanced toxicity of pesticides from co

- e xposure to PBO.

To estimate exposure concentrations, the ecological risk assessment considers applications at maximum rates. If multiple applications are allowed, the maximum amount per application and minimum interval between applications are used

– pr ovided that maximum total annual application amounts are also included in this configuration. Several EFED exposure models (e.g., PRZM

- EXAMS, T

- REX) are used to estimate likely high

- end exposure to PBO . The most sensitive toxicity endpoints are used from surrogate test species to estimate treatment

- related direct effects on acute mortality and chronic reproductive, growth and survival assessment endpoints. Toxicity tests are intended to determine effects of pesticide exposure on birds, mammals, fish, amph ibians, terrestrial and aquatic invertebrates, and plants. These tests include short

- term acute,
sub

- acute, and reproduction studies and are typically arranged in a hierarchical or tiered system that progresses from basic laboratory tests to applied field studies. The toxicity studies are used to evaluate the potential of a pesticide to cause adverse effects, to determine whether further testing is required, and to determine the need for precautionary label statements to minimize the potential adverse eff ects to non

- target animals and plants.

### 26

6. Conceptual Model

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

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

6.1. Risk Hypothesis

Risk hypotheses are specific assumptions about potential adverse effects ( i.e. , ch anges in assessment endpoints) and may be based on theory and logic, empirical data, mathematical models, or probability models (USEPA 1998). For this assessment, the risk
is stressor

- initiated, where the stressor is the release of PBO into the environmen t. The following risk hypotheses are presumed for this screening

- level assessment:

PBO, along with its three major degradates ( PBO

- alcohol, PBO

- aldehyde and

PBO

- acid ), when used in accordance with registered labels, will likely lead to off

site movement of the compound via runoff, spray drift, and eroded soil leading to exposure of nontarget plants and animals

. Based on information on the environmental fate, mode of action, direct toxicity and potential indirect effects, EFED assumes that registered uses of PBO have the potential to cause reduced survival, growth, and reproduction to non

- target terrestrial and aquatic animals and plants. In addition, PBO enhances the toxicity of other pesticides, which may result in increased risk to fish, aquatic invert ebrates, and benthic invertebrates.

PBO, along with its three major degradates ( PBO

- alcohol, PBO

- aldehyde and

PBO

- acid ), when used indoors, in accordance with current labels, may result in off

- site movement of the compound via wash

- off into surface wate rs via drains and treatment plants, leading to exposure of nontarget aquatic plants and animals. This potential exposure pathway may result in adverse effects upon the survival, growth, and/or reproduction of non

- target aquatic animals and plants.

The c onceptual model is a generic graphic depiction of the risk hypothesis. It includes the potential pesticide or stressor (PBO), the source of the pesticide and/or transport pathways, exposure media, exposure point, biological receptor types, and attribute

c hanges.

### 27 6.2. Conceptual Diagram

The conceptual site model is a generic graphic depiction of the risk hypothesis, and assumes that the insecticide synergist, PBO, having multiple outdoor agricultural and

non

- agricultural uses , is capable of affecting aquatic and terrestrial animals provided that environmental concentrations are sufficiently elevated as a result of proposed label uses. Based on an examination of the physicochemical properties of PBO, the fate and disposition i n the environment, and mode of application, a conceptual model was developed that represents the possible relationships between the stressors, ecological receptors, and the assessment endpoints. Through a preliminary iterative process of examining availab le data, the conceptual model ( i.e ., the representation of the risk hypothesis) may be refined to reflect the likely exposure pathways and the organisms that are most relevant and applicable to this assessment (see Figure 2 and Figure 3 , below). They include the total toxic residues (TTR) from the pesticide synergist, or stressor (PBO ), along with its major degradates, PBO

- alcohol, PBO

- aldehyde, and PBO

- acid

, the
sources and

/ or transport pathways, exposure media and exposure points, biological receptor types and attribute changes.

In order for a chemical to pose an ecological risk, it must reach ecological receptors in biologically significant concentrations. An exposure pa thway is the means by which a pesticide moves in the environment from a source to an ecological receptor. For an ecological exposure pathway to be complete, it must have a source, a release mechanism, an environmental transport medium, a point of exposure for ecological receptors, and a feasible route of exposure. In addition, the potential mechanisms of degradation/ transformation ( i.e. , which degradation/ transformation products may form in the environment, in which media, and how much) must be understood , especially if for the chemical, its metabolites/ transformation products are of greater toxicological concern than the parent compound. In this case, the TTR is examined. The assessment of ecological exposure pathways, therefore, includes an examinatio n of the source and potential migration pathways for constituents, and the determination of potential
exposure routes.

Under the possible uses of PBO, the sources and mechanisms of release of the compound are from ground or aerial spray or ULV application s (note that this conceptual model considers agricultural applications as well as certain non

- agricultural applications). Surface runoff from the areas of application is assumed to depend on factors such as topography, irrigation, and rainfall events. Di rect deposition may result in contamination of food items that may be consumed by terrestrial organisms. Spray drift results in contaminated adjacent areas, including bodies of water. As mentioned in Section 3 .2

, above, PBO will have a moderate tendency to move from soil to surface water, and little tendency to leach to ground water except in coarse

- textured soils. Due to the low potential for volatilization, atmospheric t ransport of PBO or its major degradates (PBO

alcohol, PBO

- aldehyde, and PBO

- acid) is unlikely. It is noted that PBO TTR is quite stable in the environment with an aquatic aerobic half

- life of 133 days (though only 5.7 days when exposed to photolytic conditions).

### 28

For aquatic receptors, the major point of exposure is through direct cont act with the water column, sediment, and pore water (gill/ integument) contaminated with spray drift (from spray application) and/or runoff from treated areas. Indirect effects to aquatic organisms (fish , aquatic

- phase amphibians and aquatic invertebrates ) can also occur through impact to various food chains. The representative aquatic receptors are certain freshwater and estuarine/ marine fish, invertebrates, and, in certain cases, aquatic plants. The major point of exposure for terrestrial animals is c onsumption of food contaminated with residues such as grass, foliage, and small insects. For plants, the point of exposure is direct contact or root uptake. The representative terrestrial receptors are mammals, birds and terrestrial plants. The attribut e changes used to assess risk to terrestrial receptors depend on the type of test ( e.g. , reduced survival, growth, or reproduction for animals and seedling emergence and vegetative vigor for plants). It should be noted, that these species do not cover all the possible species in the animal and plant kingdoms; certain taxa are considered as surrogates for other taxa. For example, fish may be considered surrogates for aquatic phase amphibians.

This conceptual model also shows details about biomagnification for a chemical (see piscivorous birds and mammals in ( Figure 2 ). However, bioconcentration of PBO is not a primary concern. PBO shows a fairly high solubility and a high K OW 

### . These properties suggest that the chemical can partition with sediments, and with organic matter suspended in the water bodies, to some degree, but also remain in solution to a significant degree. In water column, it will be slowly metabolized (75

- day half

- life), or in shallow, clear wate rs, rapdily degraded by photolysis to PBO

- alcohol, PBO

- aldehyde, and PBO

- acid. P BO TTRs may concentrate in the sediments, where they could persist. Such sediments could serve as repositories of the chemical(s) for extended periods of time and could poten tially be toxic to sediment dwelling organisms, affecting the food chain. These issues will also
be assessed in the risk assessment for PBO.

As mentioned in Section 3 , PBO will have very little tendency to partition from water to the atmosphere since it would react rapidly with hydroyl radicals. PBO

- alcohol, PBO

aldehyde, and PBO

- acid would have even less tendency to partition to air due to their much higher solubility in water. Therefore, exposure to PBO TTRs from agricultural use should take place mai nly in soil and surface water, and from consumption of plants and other food items onto which PBO is sprayed.

This risk assessment will also evaluate the potential for PBO TTRs to go down the drain with some use patterns, such as animal shampoos. Due to its high solubility and stability this pathway will also be explored, see Figure 4

.

### 29

Figure 2

. Conceptual model depicting stressors, exposure pathways, and potential effects to aquatic orga nisms from the use of PBO on agricultural and certain non

agricultural sites

. Dotted lines indicate exposure pathways that have a low likelihood of contributing to ecological risk.

**Route of exposure includes only ingestion of fish and aquatic inverts. 

### Stressor

Source

Receptors

Attribute Change PBO (and degradates) applied to agricultural or non

- agricultural use site

Spray drift

Aquatic animals
Invertebrates
Vertebrates
**Piscivorous mammals
and birds

Individual organisms
Reduced survival Reduced growth
Reduced reproduction Food chain Reduction in algae and vascular plants Reduction in prey
Mod ification of PCEs related to prey 

### availability Habitat integrity Reduction in primary productivity
Reduced cover Community change
M odification of PCEs
related to habitat Surface water/
Sediment Runoff

Aquatic Animals
Invertebrates
Vertebrates 

### Exposure
Media

Uptake/gills

or integument



### Ingestion Ingestion Atmospheric transport

Wet/dry deposition Soil Leaching to

Groundwater

Uptake/gills

or integument

Aquatic Plants

Non

- vascular
Vascular Uptake/cell, roots, leaves Riparian plants

terre strial

exposure pathways; see Figure 6.1b

### 30

Figure 3 . Conce ptual model depicting stressors, exposure pathways, and potential effects to terrestrial organisms from the use of PBO on agricultural and certain non

agricultural sites

. Dotted lines indicate exposure pathways that have a low likelihood of contributing t o ecological risk.

The conceptual model for potential risks of PBO to aquatic organisms for various indoor uses of the chemical that could potentially end up in a domestic wastewater “drain” is depicted in Figure 4 . The stressor is the chemical of concern, PBO TTRs. It is noted that the transport pathway is wastewater flow, the exposure media is the treatment facility that discharges into a surface water body of water (where it may undergo dilution), and the exposure point or route, receptor and attribute changes for aquatic organisms are similar to the conceptual model for agricultural applications. Stressor

Source

Attribute Change PBO (and degradates) applied to agricultural or non

- agricultural terrestrial
use site

Direct application Spray drift

Terrestrial
vertebrates Terrestrial
invertebrates

I ndividual organisms
Reduced survival Reduced growth Reduced reproduction Food chain Reduction in prey and food
Modification of PCEs related to prey availability Habitat integrity Reduction in primary productivity
Reduced cover Community change
Modific ation of PCEs related
to habitat Terrestrial plants grasses/ forbs, fruit, seeds (trees, shrubs) Runoff

Terrestrial
vertebrates 

### Exposure Media & Receptors Soil

Ingestion Ingestion Ingestion Dermal uptake/Ingestion Atmospheric transport

Root uptake/contact

Wet/dry deposition

Ingestion Leaching to

Groundwater Irrigation

water

### 31

Figure 4

. Conceptual model for potential risks of PBO t o aquatic organisms for various indoor uses of the chemical that could p otentially end up in the “drain ”

7. Analysis Plan

In registration review, pesticide ecological risk assessments will follow the Agency‟s

Guidelin es for Ecological Risk Assessment, will be in compliance with the paper titled “Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs, U.S. Environmental Protection Agency” (USEPA, 2004), and will be done in
accordance with Section 7 of the Endangered Species Act.

P reviously completed screening level risk assessments and exceedances of Agency levels of concern indicate a need to further examine and refine risk. Analysis of potential indirect effects on listed species is al so required. This analysis plan will be revisited and may be revised depending upon the data available in the open literature and the information submitted by the public in response to the opening of the Registration
Review docket. Stressor PBO Applications that Could Potentially End Up “Down

- the

- drain”

Source/ Transport Pathways Wastewater flow

Source/ Exposure
Media Treatment Faci lity Discharges into Surface

Waters

Exposure

Route Gill/ Integument Uptake

Receptors

Attribute Changes Aquatic Invertebrates,
Vertebrates

Individual
Vertebrates and
Invertebrates
Reduced survival or reproduction Plant Population
Reduced popul ation growth Aquatic
Plants Uptake/ Adsorption

### 32

Use information will b e retrieved from registration labels and used as inputs for estimating exposure concentrations from the various use scenarios. PBO‟s use patterns suggest potential risk concerns to aquatic and terrestrial organisms. The range of potential exposure to PB O to non

- target terrestrial organisms can vary on application method (aerial or ground), application rate, and use pattern.

7.1. Stressors of Concern

The focus of this assessment is on the total toxic residues (TTR), which include parent material, PBO

, plus major degradates: PBO

- alcohol, PBO

- aldehyde and PBO

- acid

. Available t oxicity data on pesticide mixtures (products containing multiple active ingredients) and environmental mixtures of PBO with other pesticides (those mixtures occurring in the enviro nment following application), will be presented as part of the ecological risk assessment. PBO may be applied in tank mixtures with other products approved for use on registered crops. It is expected that the toxic effect of PBO, in
combination with othe r pesticides used in the environment, is likely to be a function of many factors including, but not necessarily limited to: (1) the exposed species, (2) the co

contaminants in the mixture, (3) the ratio of PBO and co

- contaminant concentrations, (4)
differe nces in the pattern and duration of exposure among contaminants, and (5) the differential effects of other physical/ chemical characteristics of the receiving waters ( e.g. organic matter present in sediment and suspended water). Quantitatively predicting the combined effects of all these variables on mixture toxicity to any given taxa with confidence is beyond the capabilities of the available data and methodologies. However, a qualitative discussion of implications of the available pesticide mixture effe cts data on the confidence of risk assessment conclusions will be addressed as part of the uncertainty analysis.

7.2. Measures of Exposure

In order to estimate risks of PBO exposures in aquatic and terrestrial environments, all exposure modeling and resul ting risk conclusions will be made based on maximum application rates for the current use patterns. Measures of exposure are based on aquatic and terrestrial models that predict estimated environmental concentrations of PBO using maximum labeled applicati on rates and methods, as well as any mitigation measures specifically indicated on the label. The models used to predict aquatic EECs are the Pesticide Root Zone Model coupled with the Exposure Analysis Model System (PRZM/EXAMS). Also, to estimate exposu re related to releases of PBO from domestic wastewater treatment plants, the Exposure and Fate Assessment Screening Tool‟s (E

FAST2) down

- the

- drain module will be used. The model used to predict terrestrial exposure is T

- REX. The model used to derive EEC s relevant to terrestrial and wetland plants is TerrPlant. The potential for bioaccumulation for the chemical is assessed using the KABAM model, as well the results from bioconcentration in fish studies (the bioconcentration factors). These models are pa rameterized using relevant reviewed registrant

- submitted environmental fate and transport data.

### 33

PRZM (v.3.12.2, May 2005) and EXAMS (v.2.98.4.6, April 2005) are screening simulation models coupled with the input shell PE5.pl (August, 2007) to generate dai ly exposures and 1

- in

- 10 year EECs of PBO, that may occur from spray drift and runoff to surface water bodies adjacent to application sites. PRZM simulates pesticide application, movement and transformation on an agricultural field and the resultant
pest icide loadings to a receiving water body via runoff, erosion and spray drift. The EXAMS model simulates the fate of the pesticide and resulting concentrations in the water body. The standard scenario used for ecological pesticide assessments assumes appl ication to a 10

- hectare agricultural field that drains into an adjacent 1

- hectare water body that is 2 meters deep (20,000 m 3 

### volume) with no outlet. PRZM/ EXAMS is used to estimate screening

- level exposure of aquatic organisms to PBO and its transformati on products . The measure of exposure for aquatic species is the 1

- in

- 10 year return peak or rolling mean concentration. The 1

- in

- 10 year peak is used for estimating acute exposures of direct effects to aquatic organisms. The 1

- in

- 10

- year 60

- day mean is u sed for assessing chronic exposure to fish and aquatic

- phase amphibians. The 1

- in

- 10

- year 21

- day mean is used for assessing aquatic invertebrate chronic exposure.

Given the aquatic toxicity of PBO and its likelihood to occur in sediment, the Agency
will a lso consider the potential exposures resulting from benthic/ sediment concentrations (EECs). Pore water concentrations are commonly used to predict toxicity of non

- ionic substances in sediments and characterize exposure to organisms that spend time in or near sediments (Di Toro et al. 1991). PRZM/ EXAMS estimates 1

- in

- 10

- year peak and

21

- day mean EECs for pore water.

To estimate exposure related to releases of PBO to domestic wastewater treatment, the Agency will rely on the Office of Pollution Preventio n and Toxics (OPPT) model, Exposure and Fate Assessment Screening Tool (E

- FAST, version 2.0, 2007, or EFAST2). From this model, the Agency used the “Down

- the

- Drain” module, which is designed for

releases to domestic wastewater treatment. It is suitable for all the sources of PBO that could potentially be exposed through a “down

- the

- drain” scenario. The model provides screening level estimate concentrations of chemicals in surface water that may result from household uses and the disposal of consumer product s into wastewater using a few simple input parameters (production volume and fraction of the chemical removed during wastewater treatment). Additionally, the Agency will evaluate any available treatability data to help characterize risk from PBO or degrad ates that might pass through water treatment plants.

Exposure estimates for terrestrial animals assumed to be in the target area are derived using the T

- REX model (version 1.3.1, 12/07/2006). For pesticides such as PBO, which can be applied as a dust, th is includes the amount of pesticide per square foot, used in

LD 50 

### per square foot risk assessment calculations. EECs for terrestrial plants inhabiting dry and wetland areas are derived using TerrPlant (version 1.2.2, 12/26/2006). Th is model uses estimates of pesticides in runoff and in spray drift (assumed to be 0% for granulars) to calculate EECs. EECs are based upon solubility, application rate and minimum incorporation depth.

### 34

As indicated in Table 3.1 and its associated text in Section 3 , PBO appears to have some potential to bioaccumulate in aquatic and terrestrial organisms ; however, available bioconcentration studies in fish do not suggest that bioconcentration is a primary concern in fish, although PBO‟s bioconcentration pote ntial in invertebrates has not been
evaluated.. . The potential for bioaccumulation of PBO will be further examined in the
risk assessment. B ioaccumulation will be assessed using the results from bioaccumulation in fish studies, as well as the KABAM model (K OW 

### (based) Aquatic BioAccumulation Model, version 1.0, 2009), adjusting for biotransformation rates. KABAM is used to estimate potential bioaccumulation of hydrophobic organic pesticides in freshwater aquatic ecosystems and risks to mammals and birds c onsuming aquatic organisms which have bioaccumulated these pesticides.

To better determine availability of PBO and its major degradates, more information is needed on aerobic soil metabolism, aerobic and anaerobic aquatic metabolism and absorption/desorpt ion. To determine availability and exposure to terrestrial organisms that feed on plants, foliar dissipation data are needed . See Sec tion 9 for additional
details.

7.3. Measures of Effect

Ecological effects data are used as measures of direct and indir ect effects to biological receptors. Data are typically obtained from registrant

- submitted studies or from literature studies identified by ECOTOX. The ECOTOX database provides more ecological effects data in an attempt to bridge existing data gaps. ECO TOX is a source for locating single chemical toxicity data and potential chemical mixture toxicity data for aquatic life, terrestrial plants, and wildlife. ECOTOX was created and is maintained by the USEPA, Office of Research and Development, and the Nati onal Health and Environmental Effects Research Laboratory's Mid

- Continent Ecology Division.

The acute measures of effect used for animals in this assessment are the LD 50 

### , LC 50 

### and

EC 50 

### . LD stands for "Lethal Dose", and LD 50 

### is the amount of a material, g iven all at once, that is estimated to cause the death of 50% of the test organisms. LC stands for
“Lethal Concentration” and LC 50 

### is the concentration of a chemical that is estimated to kill 50% of the test organisms. EC stands for “Effective Concentrat ion” and the EC 50 

### is the concentration of a chemical that is estimated to produce a specific effect in 50% of the test organisms. Endpoints for chronic measures of exposure for listed and non

- listed
animals are the NOAEL and NOAEC. NOAEL stands for “No O bserved

- Adverse

Effect

- Level” and refers to the highest tested dose of a substance that has been reported to have no harmful (adverse) effects on test organisms. The NOAEC ( i.e. , “No

Observed

- Adverse

- Effect

- Concentration”) is the highest test concentratio n at which none of the observed effects were statistically different from the control. For non

- listed plants, only acute exposures are assessed ( i.e. , EC 25 

### for terrestrial plants and EC 50 

### for aquatic plants); for listed plants either the NOAEC or EC 05 

### is used.

Information on the potential effects of PBO on non

- target animals is also collected from the Ecological Incident Information System (EIIS). The EIIS is a database containing

### 35

adverse effect (typically mortality) reports on non

- target organisms where such effects have been associated with the use of pesticides. Information on incidents involving avian species is also provided through the Avian Monitoring Information System (AIMS), which is maintained by the American Bird Conservancy.

Where availab le, sub

- lethal effects observed in both registrant

- submitted and open literature studies will be evaluated qualitatively. Such effects may include behavioral changes ( e.g. , lethargy and changes in coloration). Quantitative assessments of risks, though, a re limited to those endpoints that can be directly linked to the Agency‟s assessment endpoints of impaired survival, growth and reproduction.

The assessment of risk for direct effects to non

- target organisms makes the assumption
that the toxicity of PBO to birds is similar to terrestrial

- phase amphibians and reptiles. The same assumption is made for fish and aquatic

- phase amphibians.

Several toxicity studies are needed to better assess the potential risk of PBO exposure to

non

- targ et organisms , including passerine acute oral toxicity, honey bee acute contact toxicity (from a typical end

- use product, TEP), fish full life cycle toxicity, fish and invertebrate chronic toxicity to saltwater species, sediment toxicity (both freshwater an d saltwater), aquatic and terrestrial plant toxicity data (using TEP) , and a data set to address the acute synergistic affects of PBO with ot her pesticides to freshwater fish and
invertebrat e s

7.4. Integration of Exposure and Effects

Risk characterization is the integration of exposure and ecological effects characterization to determine the potential ecological risk from the use of pesticides and the likelihood of
direct and indirect effects to non

- target organisms in aquatic and terrestrial habitats. Th e exposure and toxicity effects data are integrated in order to evaluate the risks of adverse ecological effects on non

- target species. For the assessment of risks, the risk quotient (RQ) method is used to compare exposure and measured toxicity values. E ECs are divided by acute and chronic toxicity values. The resulting RQs are then compared to the Agency‟s Levels of Concern (LOCs) (USEPA 2004). These criteria will be used to indicate when PBO‟s uses, as directed on the label, have the potential to caus e adverse
direct or indirect effects to non

- target organisms. In addition, incident data from the EIIS will be considered as part of the risk characterization.

7.5. Endangered Species Assessments

Consistent with the Agency‟s responsibility under the Enda ngered Species Act (ESA), the Agency will evaluate risks to Federally

- listed threatened and/or endangered (listed) species from registered uses of PBO. This assessment will be conducted in accordance with the Overview Document (USEPA 2004), provisions of the ESA, and the Services‟ Endangered Species Consultation Handbook (USFWS/NMFS, 2004 ).

### 36

The assessment of effects associated with the registration of PBO is based on an action area. The action area is considered to be the area directly or indirectly affe cted by the federal action, as indicated by the exceedance of Agency Levels of Concern (LOCs) used to evaluate direct or indirect effects. The Agency‟s approach to defining the action area under the provisions of the Overview Document (USEPA 2004) conside rs the results of the risk assessment process to establish boundaries for that action area with the understanding that exposures below the Agency‟s defined LOCs constitute a no

- effect threshold. For the purposes of this assessment, attention will be focu sed on the footprint of the action ( i.e. , the area where PBO application occurs), plus all areas where offsite transport may result in potential exposure that exceeds the Agency‟s LOCs. Specific measures of ecological effect that define the action area fo r listed species include any direct and indirect effects and/ or potential modification of its critical habitat, including reduction in survival, growth, and reproduction as well as the full suite of sub

- lethal
effects available in the effects literature. Therefore, the action area extends to a point where environmental exposures are below any measured lethal or sub

- lethal effect threshold for any biological entity at the whole organism, organ, tissue, and/ or cellular level of organization. In situations where it is not possible to determine the threshold for an observed effect, the action area is not spatially limited and is assumed to be the entire
United States.

Probit Analysis

Analysis of raw data from the aquatic acute toxicity studies for PBO will be used to estimate probabilities of effects to aquatic and terrestrial animals. Slope estimates along with 95% conficence intervals will be used. When slope data is unavailable, a default slope of 4.5 is used with confidenct intervals of 2 and 9 ( Urban and Cook, 1986 ).

7.6. Drinking Water Assessment

At the time of the risk assessment, a water assessment will be done considering the following:

* New data has been submitted to the agency.

* Changes in the label uses and rates.

* Any mitigation that has b een proposed in the previous assessments.

* New models has been developed that used for drinking water assessment.

A drinking water assessment will be conducted to support future human health risk assessments of PBO should it be required. The drinking wat er assessment will incorporate model estimates of PBO in surface and ground waters. Concentrations in surface waters will be estimated using FQPA Index Reservoir Screening Tool (FIRST, v.1.1.1, 12/18/07) (or subsequently using PRZM/ EXAMS, with the Index Reservoir

- see description above, if refinements are required). Ground water estimates of concentrations will be estimated using the Screening Concentration in Ground Water (SCI

- GROW) model (v.2.3, July 2003). The drinking water assessment will also inc lude a summary of available surface and ground water monitoring data.

### 37

Drinking water exposure of PBO to avian and mammalian species will be screened to determine if this is a potential pathway of concern. The S creening I mbibition P rogram (SIP v.1.0, Rele ased June 15, 2010) will be used to calculate an upper bound estimate of exposure using PBO‟s solubility, the most sensitive acute and chronic avian toxicity endpoints, and the most sensitive acute and chronic mammalian toxicity endpoints.

7.7. Endocrine Disruptor Screening Program

As required under FFDCA section 408(p), EPA has developed the Endocrine Disruptor Screening Program (EDSP) to determine whether certain substances (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 o f 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. Chemicals that go through Tier 1 screening and are found to have the potential to inter act 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 available data. Tier 2 testing is designed to identify any
adverse endocrine related effe cts caused by the substance, and establish a dose

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

Between October 2009 and February 2010, EPA issued test orders/data call

- ins for the first group of 67 chemicals, which contains 58 pestici de active ingredients and 9 inert ingredients. This list of chemicals was selected based on the potential for human exposure through pathways such as food and water, residential activity, and certain post

application agricultural scenarios. This list sho uld not be construed as a list of known or likely endocrine disruptors. PBO was included in the list and test orders were issued in November, 2009.

For further information on the status of the EDSP, the policies and procedures, the list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/.

7.8. Preliminary Identification of Data Gaps

The Agency does foresee requiring additional fate and ecological effects studies prior to conducting th e planned assessments. Data gaps, uncertainties and potential paths forward
for the assessment of PBO are described below.

### 38 Fate

After evaluation of the available data for PBO, the fate da ta gaps for registration review
consist of the following. These studies have not been previously requested :

Guideline Number: 835.4100

, Aerobic Soil Metabolism
Guideline Number: 835.4300

, Aerobic Aquatic Metabolism
Guideline Number: 835.4400

, Anaerobic Aquatic Metabolism Guideline Number: 835.1230, Adsorption/Desorp tion Guideline Number: 835.6100, Analytical Method for Residues in Soil and
Sediment Guideline Number: 835.6200, Analytical Method for Residues in Water
Guideline Number: 875. 2100 Dislodgable Foliar Residues (modified for total
foliar residue )

– protocol needs to be submitted prior to study initiation

Effects

After eva luation of the available data for PBO, the effects da ta gaps for registration
review are listed below, most have already been requested in previous data call

- ins:

Previously requested stud ies :

Guideline Number: 850.1075, Study T itle: Fish Acute Toxicity Test with

TEP (typical end

- use product)

. TEP studies are required for pesticides that may be directly applied to water. Guideline Number: 850.1010, Study Title: Aquatic Invertebrate Acu te Toxicity Test, Freshwater Daphnid with TEP. TEP studies are required for pesticides that may be directly applied to water. Guideline Number: 850.1350, Study Title: Aquatic Invertebrate Life Cycle Toxicity (estuarine/marine) with TGAI (technical grad e active ingredient)

. Guideline Number: 850.1500, Full Life Cycle Fish Test ( freshwater ) with

TGAI.
Guideline Number: Non

- guideline ( at time of submission, current Guideline Numbers 850.1760; 850.1770; 850.1780) , Sediment Toxicity with TEP (freshwater an d saltwater). Guideline Number: 850.4100, Seedling Emergence Tier I study to determine the EC 25 

### and NOAEC using TEP. Guideline Number: 850.4150, Vegetative Vigor Tier I study to determine the

EC 25 

### and NOAEC using TEP.

New Data Requirements not Previous ly R equested :

Guideline Numbers: 835.6100, Study Title: Analytical Method (and Associated Independent Laboratory Validation) for Residues in Soil and Sediment
Guideline Number 835.6200: Study Title: Analytical Method (and Associated Independent Laboratory Validation) for Residues in Water 

### Guideline Number: 850.2100, Study Title: Acute Av ia n Oral Toxicity Test using a Passerine species with TGAI.
Guideline Number: 850.3020, Honey Bee Acute Contact Toxicity using TEP. Guideline Number: 850.1075, Study T itle: Fish Acute Toxicity Test with major degradates.

### 39 Guideline Number: 850.1075, Study Title: Fish Acute Toxicity Test, data addressing the synergistic interaction of pesticides and PBO. These studies are expected to be modified guideline studies, and protocols need to be submitted prior to study initiation. This requirement was included in the RED; however, the RED specified that synergism data were only required for

TEPs . Data are currently being requested to address synergism with all pesticide ac tive ingredients (and other chemicals with similar modes of action)
with which PBO is recommended for co

- application. Guideline Number: 850.1010, Study Title: Aquatic Invertebrate Acute

To xicity Test, Freshwater Daphnid , data addressing the synergisti c interaction of pesticides and PBO. These studies are expected to be modified guideline studies, and protocols need to be submitted prior to study initiation. This requirement was included in the RED; however, the RED specified that synergism data were only required for TEPs. Data are currently being requested to address synergism with all pesticide active ingredients (and other chemicals with similar modes of action) with which PBO is recommended for

co

- application. Guideline Number: 850.1400, Fis h Early Life

- Stage Test (estuarine/marine)
with TGAI. Guideline Number: 850.4400, Aquatic Plant Tier I study using Lemna spp . to determine EC 50 

### and NOAEC using TGAI. Guideline Number: 850.5400, Aquatic Plant Tier I Algal toxicity study to
determine EC 50 

### an d NOAEC using TGAI.

For registration review, the following studies are being requested to fulfill data gaps:

Guideline Number: 835.4100 Study Title: Aerobic Soil Metabolism As per OCSPP Harmonized Test Guidelines; Aerobic and anaerobic studies with one soil type are generally sufficient for the evaluation of transformation pathways. Rates of
transformation should be determined in at least three additional soils. A t this time, EPA has only one acceptable study done with one soil.

Guideline Number : 835. 4300 Study Title: Aerobic Aquatic Metabolism As per OCSPP Harmonized Test Guidelines; At least two sediments and their associated waters are used for both the aerobic and the anaerobic studies respectively. EPA has only one upgradable to acceptable study done with one sediment.

Guideline Number : 835.4400 Study Title: Anaerobic Aquatic Metabolism As per OCSPP Harmonized Test Guidelines; At least two sediments and their associated waters are used for both the aerobic and the anaerobic studies respectivel y. EPA has only one supplemental study done with one sediment.

Guideline Number : 835.1230

### 40

Study Title: Adorption

- Desorption (Batch E q uilibrium ) As per OCSPP Harmonized Test Guidelines; At least two soils should be used. EPA has only one acceptable study done with one soil.

Guideline Number: 875.2100 (modified) Study Title: Dislodgable Foliar Residues (modified for total foliar residue)

– protocol needs to be submitted prior to study initiation

. The risk assessments showed a potential for chronic ris k to mammals and birds from PBO using the default half

- life of 35 days. A measured foliar dissipation rate, if shorter than 35 days, might remove the presumption of risk.

Guideline Number: 835.6100 Study Title: Analytical Method (and Associated Independe nt Laboratory Validation) for Residues in Soil and Sediment Environmental chemistry methods in soil or sediment have not been submitted in support of submitted terrestrial or aquatic field dissipation studies of piperonyl butoxide (PBO). An independently validated environmental chemistry method in soil (and in sediment if procedures for sediment differ from those for soil) is necessary to evaluate the results of submitted terrestrial field dissipation studies and to provide outside agencies an analytical method with which to monitor for PBO residues in soil and aquatic sediment. In the absence of an independently validated environmental chemistry method in soil and sediment, submitted terrestrial field dissipation studies are not acceptable and entities

o utside the Agency may lack a chemical

- specific method for analyses in soil and sediment. An independently validated environmental chemistry method will be used to evaluate submitted terrestrial field dissipation studies in which it is used and will be mad e available for enforcement and monitoring purposes at the federal, state, and local levels.

Guideline Number: 835.6200 Study Title: Analytical Method (and Associated Independent Laboratory Validation) for Residues in Water Environmental chemistry methods in water have not been submitted in support of submitted aquatic field dissipation studies. An independently validated environmental chemistry method in water is necessary to evaluate the results of submitted aquatic field dissipation studies and to prov ide outside agencies an analytical method with which to
monitor for PBO residues in water. In the absence of an independently validated environmental chemistry method in water, submitted aquatic field dissipation studies are not acceptable and entities ou tside the Agency may lack chemical

- specific methods for analyses in water. An independently validated environmental chemistry method will be used to evaluate submitted aquatic field dissipation studies in which it is used and will be
made available for en forcement and monitoring purposes at the federal, state, and local
levels.

Guideline Number: 850. 1075 Study Title: Fish Acute Toxicity Test (freshwater) with TEP and major degradates

. No acceptable acute studies for PBO TEP have been submitted for fish

. Since PBO can be directly applied to water, EPA needs data on the formulated product. Without

### 41

toxicity data on the range of TEPs produced, the Agency woud have to presume acute toxicity to listed and non

- listed fish and aquatic

- phase amphibians , but wou ld not be able to quantify the risk.

Guideline Number: 850. 1075 Study Title: Fish Acute Toxicity Test , data addressing synergistic affect of PBO with each pesticide with which it may be simultaneously applied. No acceptable acute studies have been submit ted for fish which address the synergistic affect of PBO with other pesticides. Due to fate charactersistics and registered uses of

PBO there may be significant exposure in water bodies. PBO is a pesticide synergist. Therefore, it is used in combination with other pesticides to enhance their effectiveness (toxicity) to target organisms. Assessing potential ecological risks of PBO requires evaluating potential exposure and toxicity of the active ingredient (PBO alone) and evaluating the enhanced toxicity of other pesticides with which it is simultaneously applied. Given the number of chemicals with which PBO may be simultaneously applied, designing a study that examines the range of synergistic effects is difficult. A comprehensive evaluation of potenti al synergistic effects of PBO and all chemical s with
which it may be simultaneously applied will require the development and review of a large body of data. The Agency is interested in obtaining data on (or bridging data to) pesticide active ingredients (i n addition to other chemicals with similar modes of action)
that are co

- applied (or expected to be co

- applied) with PBO for its synergistic properties including those that are formulated with PBO and those that are otherwise recommended for mixing with PBO prior to application. The Agency recognizes that this data set is extensive and is willing to consider options for a reduced data set that evaluates the nature of PBO synergy with a limited number of compounds, and allows bridging to
these more extensive synergy studies from reduced data sets for other chemicals. The goal of obtaining this set of data is to determine the potential range of magnitudes of synergistic effects for pesticide active ingredients that are co

- applied with PBO for the purpose of e nhancing efficacy due to synergism. Protocols need to be submitted to the Agency prior to study initiation. Without this data set, the Agency wou l d have to presume acute toxicity to listed and non

- listed invertebrates, but would not be able to quantify th e risk.

Guideline Number: 850.1010 Study Title: Aquatic Invertebrate Acute To xicity Test, Freshwater Daphnid , with

TEP No acceptable acute studies for PBO TEP have been submitted for aquatic invertebrates. Since PBO can be directly applied to water, EP A needs data on the formulated product. Without toxicity data on the range of TEPs produced, the Agency woud have to presume acute toxicity to listed and non

- listed fish, but would not be able to quantify the risk. A formulated product that is applied directly to water needs to be the subject of the study.

Guideline Number: 850.1010 or 850.1035 Study Title: Aquatic Invertebrate Acute To xicity Test, Freshwater Daphnid , data addressing synergistic affect of PBO with each pesticide with which it is
simu ltaneously applied.

### 42

No acceptable acute studies have been submitted for invertebtatesd which address the synergistic affect of PBO with other pesticides. Due to the fate charactersistics and the registered uses of PBO there may be significant exposure to water bodies. PBO can act as a synergist to other pesticides. In order to evaluate the nature of this synergy, data on the synergistic interaction of each pesticide is needed to complete an an accurate risk assessment. This will require the development a nd review of a large body of data. The Agency is interested in obtaining data on (or bridging data to) pesticide active ingredients (in addition to other chemicals with similar modes of action) that are co

- applied with PBO for its synergistic properties i ncluding those that are formulated with PBO and those that are otherwise recommended for mixing with PBO prior to application. The Agency recognizes that this data set is extensive and is willing to consider options for a reduced
data set that evaluates t he nature of PBO synergy with a limited number of compounds, and allows bridging to these more extensive synergy studies from reduced data sets for
other chemicals. The goal of obtaining this set of data is to determine the potential range of magnitudes of synergistic effects for pesticide active ingredients that are co

applied with PBO for the purpose of enhancing efficacy due to synergism. Without this data set, the Agency wou l d have to presume acute toxicity to listed and non

- listed
invertebrates , bu t would not be able to quantify the risk.

Guideline Number: 850.1350 Study Title: Aquatic Invertebrate Life Cycle Toxicity ( Saltwater ) with TGAI No acceptable chronic studies for PBO have been submitted for estuarine/ marine
invertebrates . The acute tox icity of PBO to estuarine/marine invertebrates and environmental fate properties indicate the potential for chronic exposure and effects to animals in this taxon, per 40 CFR Part 158 data requirements. The persistence of PBO in water is expected to substa ntially exceed the 4

- d half life criterion (75 d for parent, 133 d for total toxic residues, Table 3 )

. Chronic toxicity data are required per 40 CFR Part 158.630 due to the potential for direct application of PBO to the estuarine/marine environment, acute toxicity value that is <1 ppm (0.23 for the oyster), and the expected peak EECs (58 to 160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 13 

### ) exceed 0.01 of the acute toxicity values (this would be 4.9 ppb for mysid and 2.3 ppb for oysters). Without this study, the Agency would have to presume chronic risk
to listed and non

- listed estuarine/marine invertebrate s , but would not be able to quantify
the risk.

Guideline Number: 850

- 1400 Study Title: Fish Early Life Stage (Saltwater) with TGAI No acceptable chronic studies for PBO have been submitted for marine fish. The acute toxicity of PBO to estuarine/marine fis h and environmental fate properties indicate the potential for chronic exposure and effects to animals in this taxon, per 40 CFR Part 158 data requirements. Chronic toxicity data are required per 40 CFR Part 158.630 due to the potential for direct applica tion of PBO to the estuarine/marine environment, acute toxicity value that is <1 ppm (0.23 for the oyster), and the expected peak EECs (58 to

13 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 43

160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 14 

### ) exceed 0.01 of the acute toxicity values (this would be 39.4 ppb for sheepshead minnows to 2.3 ppb for
oysters , MRIDs 42540304 and 42540305 ). Without this study, the Agency would have to presume chronic risk to listed and non

- listed estuarine/marine fish, but would not be able to quantify the risk.

Guideline Number: 850.1500 Study Title: Full Life Cycle Fish Test (Freshwater) with TGAI. PBO and its major degradates are persistent, mobile and may pass throu gh wastewater
treatment processes. PBO may also be applied directly to both freshwater and
estuarine/marine environments. Since the expected peak EECs (58 to 160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, pota to, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 17 

### ) exceed 0.1 of the early life stage study , a fish life

- cycle test is required. This DCI remains unfulfilled

. Without this study, the Agency would have to presume chronic risk to listed and non

- listed fish and aquatic

phase amphibians , but would not be able to quantify the risk.

Guideline Number: 850.1760; 850.1770; 850.1780

- Study Title: Whole sediment:
chronic invertebrates freshwater and marine For PBO, available information indicates that b enthic organisms may be exposed via run

off or spray drift applications used in agricultural, forest, and residential settings , as well as direct applications to water

. The panel 1999 SAP panel called for sediment toxicity testing for pyrethroids (see Section 1.0 for more details); afterward , the new CFR Part 158 requirements include d sediment toxicity tests

. The new data requirements includ e chronic sediment toxicity studies for freshwater and marine organisms. The criteria are met for requiring chronic sediment toxicity studies for PBO due to its half

- life of 14d in aerobic soil and 75d in aerobic water (MRIDs 43806401 and 43803401 both as amended 5/17/2004), log Kow of 4.75 and Koc of up to1152 (MRID 43673802 ) and expected peak EECs (58 to 160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco c hapter 17 

### ) which
exceed 0.1 of the acute LC/EC 50 

### (490*0.1 = 49 ppb for M. bahia, MRID 43901801).

For sediment studies, tests on Hyalella azteca

, Chironomus dilutus , and Leptocheirus plumulosus are requested. Although both are freshwater species, Hyalell a and
Chironomus differ substantially in their ecological niche ( i.e. , epibenthic vs. infaunal species). Furthermore, Hyalella and Chironomus differ significantly in their physiology and life history, with Chironomus being the only sediment test species u ndergoing metamorphosis and emergence from an aquatic to a terrestrial life stage. There is also evidence suggesting Hyalella is among the more sensitive invertebrates to some pyrethroids based on water column tests (Anderson et al. 2006, Maund et al. , 20 02). PBO has the potential to enter estuarine/marine water bodies based on current usuage patterns that include coastal areas. Therefore, testing is required for Leptocheirus plumulosus , an estuarine/marine sediment

- dwelling invertebrate species.

14 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 44

Guidelin e Number: 850.4400 Study Title: Aquatic Vascular Plant Growth

- Lemna spp. Tier I/II with TGAI No acceptable studies for PBO have been submitted for vascular aquatic plants. The Agency has finalized its update to the data requirements in 40 CFR Part 158. In these updated data requirements, which were promulgated on October 26, 2007, vascular plant testing is required for pesticides such as PBO with outdoor uses. Tier I testing is required, followed by Tier II if required by Tier I results as specified in Ti er I guidelines.

Guideline Number: 850.5400 Study Title: Algal T oxicity test
, Tier I/II with TGAI No toxicity data are currently available to assess the risk of PBO to aquatic nonvascular plants. Since PBO has outdoor uses, Tier I/II aquatic nonvascular plant studies are required. These phytotoxicity data are needed to evaluate the level of pesticide exposure

to non

- target aquatic plants and to assess the impact of pesticides on endangered and threatened plants. Tier I testing is required, followed by Tier II if required by Tier I results as specified in Tier I guidelines.

Guideline Number: 850

. 3020 Study Title: Honey Bee Acute Contact Toxicity using TEP Terrestrial invertebrate toxicity data are required to quantitatively assess the potential impact s on this group of organisms. Data are needed from the honey bee acute contact study due to wide spread use and possible drift to off site vegetation in bloom. Available data (MRID 41969009) show PBO to be moderately toxic to practically

non

- toxic to hon ey bees (LD 50 

### > 25 μ g/bee)

. Since PBO acts as a synergist insecticide, the effects of a typical end

- use product may be much greater.

Guideline Number: 850

- 2100 Study Title: Passerine Acute Avian Oral Although an acute avian oral study was received for both the Mallar d duck and Bobwhite quail, the Agency updated its data requirements in 40 CFR Part 158 (October 26, 2007) to include an acute oral toxicity study for both a passerine species and either a waterfowl or an upland game species. Prior to starting toxicity tes ting, a protocol will need to be provided for review. Many passerine species utilize agricultural fields, forests, residential areas and surrounding areas, and, therefore, have the potential to be exposed to pesticides used in agricultural, forest, and res idential settings. It is likely that, for most pesticide use patterns, passerines are more likely to be exposed to pesticides than upland game species and waterfowl. Passerines are smaller in size and generally have faster metabolisms than
the waterfowl an d upland game bird species traditionally used in avian toxicity tests which could impact their sensitivity to chemicals.

Guideline Numbers: 850. 41 00 and 850. 4 1 50 Study Title: Vegetative vigor and Seedling emergence, Tier I/II with TEP No acceptable toxici ty data are currently available to assess the risk of PBO to non

- target terrestrial plants. Since PBO has outdoor uses, vegetative vigor and seedling emergence studies are required. These phytotoxicity data are needed to evaluate the level of

### 45

pesticide ex posure to non

- target terrestrial and aquatic plants and to assess the impact of pesticides on endangered and threatened plants. Results from Tier I tests very often necessitate the performance of a Tier II test. If a tested terrestrial species exhibits a 25 percent or greater detrimental effect in a Tier I study, a Tier II study is required. If the registrant chooses to only submit a Tier II study, a Tier I study will not be required.

Guidance on Testing with Typical end

- use products (TEP) According to the Part 158 data requirements, testing on the typical end

- use product may be required for aquatic toxicity tests when any of the following conditions exist:
1. The end

- use product will be introduced directly into the aquatic environment.
2. The maxim um expected environmental concentration or estimated environmental concentration in the aquatic environment is greater than or equal to

one

- half the LC 50 

### or EC 50 

### of the TGAI. 3. An ingredient in the end

- use formulation other than the active ingredient is expected to enhance the toxicity of the active ingredient or cause toxicity to aquatic organisms.

A Typical End

- Use Product is defined in the Pesticide Assessment Guidelines Subdivision J Hazard Evaluation: Nontarget plants on Part 120

- 2(1) on Page 18 as “a pesticide product that is representative of a major formulation category ( e.g ., emulsifiable concentrate, granular product, wettable powder) and pesticide group ( e.g ., herbicide, fungicide, insecticide etc .) and contains the active ingredient of the ap plicant‟s product.” (Holst and Ellwanger, 1982)

.

Page 5 of the Pesticide Assessment Guidelines Subdivision J Hazard Evaluation: Nontarget plants provide additional information on what TEP data should be tested for toxicity testing in the following excerp t.

“The Agency seeks to avoid imposing a burden of duplicative testing on applicants for registration. Therefore, where 40 CFR Part 158 specifies that the test substance should be a representative end

- use product, testing may be performed using the formu lation in question (end

- use product being registered) or similar, yet representative, end

- use product. It is not necessary to repeat the test using other similar products.” (Holst and Ellwanger, 1982).

When TEP data are requested, data should be submitte d for the different formulations,

e.g ., wettable powder, emulsifiable concentrate, granular, along with a rationale as to why the TEP is representative of other similar end

- use products. Acute aquatic toxicity studies conducted with the Typical End

- Use Pro duct (TEP) may be used to assess effects as a result of exposure to spray drift only and reflect potential effects from a brief exposure to the formulation. Therefore, appropriate TEPs should be selected from formulations that are registered for agricultur al uses, not residential.

Additional Programs:

Study Title: Endocrine Disruptor Screening Program

### 46

PBO is part of the Endocrine Disruptor Screening Program; certain data has been required for the chemical under the program (DCI on 11/19/09; 90

- day respon se by 02/27/10). Please, refer to the website: http://www.epa.gov/endo/

. As required under FFDCA section 408(p), EPA has developed the Endocrine Disruptor Screening Program (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, and or thyroid (E, A, or T) hormonal systems. Chemicals 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 av ailable 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.

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. This list of chemicals was selected based on the potential for human exposure through pathways such as food and water, r esidential activity, and certain post

application agricultural scenarios. This list should not be construed as a list of known or likely endocrine disruptors.

PBO is among the group of 58 pesticide active ingredients on the initial list to be
screened un der the EDSP. The Agency will review the EDSP Tier 1 data and any “other scientifically relevant information” submitted in response to test orders. Based on this review the Agency will determine the need for additional testing. For further information

on the status of the EDSP, the policies and procedures, the list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/

.

Study Title: POTW Effluent M onitoring and POTW Treatability Study PBO is part of an effort to determine amount s of pyrethroids making it through publically

- owned treatment works (POTWs). T he Agency is requiring bench scale treatability studies for pyrethroids , to assess amount s that would degrade during

treatment, remain in biosolids, or remain in waste water.

Other Information Needs

There is specific information that will assist the Agency in refining the ecological risk assessment, including any species

- specific effects determina tions. The Agency is very much interested in obtaining the following information:

1. confirmation on the following label information

### 47 a. frequency of application, application intervals, and maximum number of applications per season
b. geographic limitations on use

2. name s of chemicals that are co

- applied with PBO for its synergistic properties including those that are formulated with PBO and those that are otherwise recommended for mixing with PBO prior to application.

3. use or potential use distribution (e.g., acreage and geographical distribution of relevant crops)

4. use history
5. median and 90 th 

### percentile reported use rates (lbs. a.i./acre) from usage data

– national, state, and county

6. application timing (date of first application and application intervals) by crop

–

na tional, state, and county

7. sub

- county crop location data

8. usage/use information for non

- agricultural uses (e.g., forestry, residential, rights

of

- way)

9. directly acquired county

- level usage data (not derived from state level data)

a. maximum reported use rate (lb s. a.i./acre) from usage data

– county
b. percent crop treated

– county

c. median and 90 th 

### percentile number of applications

– county
d. total pounds per year

– county

e. the year the pesticide was last used in the county/sub

- county area
f. the years in which the pestici de was applied in the county/sub

- county area
10. typical interval (days)

11. state or local use restrictions

12. ecological incidents (non

- target plant damage and avian, fish, reptilian, amphibian and mammalian mortalities) not already reported to the Agency

13. monitorin g data

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

### 48

8. References

Amweg, E.L. , D.P. Weston, C.S. Johnson, J. You and M.J. Lydy. 2006. Effect of Piperonyl Butoxide on Permethrin Toxicity in the Amphipod Hyalella azteca

. Environmental Toxicology and Chemistry

, Vol. 25, No. 7, pp. 1817

– 1825.
Anderson et al. 2006, Barile, F. A. 2004. Clinical Toxicology: Principles and
Mechanisms . Boca Raton, FL: CRC Press

. Barile, F. A. 2004. Clinical Toxicology: Principles and Mechanisms . Boca Raton, FL:
CRC Press.

, DiToro, D. M., Zarba, C. S., Hansen, D. J., Berry, W. J., Schwartz, R. C., Cowan, C. E., et al. 1991. Technical basis for establishing sediment quality criteria for nonionic organic chemicals using equilibrium partitioning. Environmental Toxicology and Chemistry, 10 , 1541

- 1586.
Farm Chemicals Handb ook 2002: Global Guide to Crop Protection . Meister Publishing Company. ISBN13: 9781892829054

. ISBN10: 1892829053 Gibly, R. L., & Sullivan Jr., J. B. 2001. Chapter 103. Pyrethrins. In J. B. Sullivan Jr. & G. R. Krieger (Eds.), Clinical Principles of Env ironmental Health . Philadelphia, PA: Lippincott Williams & Wilkins. Hodgson, E., & Smart, R. C. (Eds.). 2001. Introduction to Biochemcial Toxicology (Third ed.). New York: Wiley

- Interscience. Holst, R. W., & Ellwanger, T. C. 1982. Pesticide Assessment Gui delines. Subdivision J. Hazard Evaluation: Nontarget Plants . EPA

- 540/09

- 82

- 020. October 1982. Office of Pesticide Programs. Office of Pesticides and Toxic Substances. United States Environmental Protection Agency. Lewis, R. A. 1998. Lewis' Dictiona ry of Toxicology . In R. A. Lewis (Ed.). Boca Raton:
Lewis Publishers

. S.J. Maund, M.J. Hamer, M.C. Lane, E. Farrelly, J.H. Rapley, U.M. Goggin and W.E. Gentle, Partitioning, bioavailability, and toxicity of the pyrethroid insecticide Cypermethrin in sedimen ts, Environ. Toxicol. Chem . 21 (1) (2002), pp. 9

– 15 Morton, T. 2004. Piperonyl Butoxide: Revised Anticipated Residues and Acute probabilistic and Chronic Dietary Exposure Assessment for the Reregistration Eligibility Decision. D310032; November 23, 2004. 

### Urban, J.D., and Cook, N.J. (1986) Ecological Risk Assessment: Standard Evaluation Procedures. Report No. EPA 540/9

- 85

- 001. US Environmental Protection Agency, Hazard Evaluation Division, Washington, D.C. Available from NTIS (National Technical Information Service), Springfield, Virginia 22161, as PB 86

- 247

- 657.
USEPA. 1998. Guidelines for Ecological Risk Assessment . United States Environmental Protection Agency (USEPA). Risk Assessment Forum. Office of Research and Development. Available at http://cfpub. epa.gov/ncea/cfm/recordisplay.cfm?deid=12460 (Accessed June 19, 2009).
US EPA. 2000. Prediciton of sediment toxicity using consensus

- based freshwater sediment quality guidelines. EPA 905/R

- 00/007.
USEPA. 2003. Technical basis for the derivation of equilibri um partitioning sediment benchmarks (ESBs) for the protection of benthic organisms: Nonionic organics

### 49 (draft) . Office of Research and Development. United States Environmnetal Protection Agency. USEPA, 2004. Overview of the Ecological Risk Assessment Pro cess in the Office of Pesticide Programs, US Environmental Protection Agency. Endangered and Threatened Species Effects Determinations. Jan. 23, 2004. USEPA, 2006 a

. Reregistration Eligibility Decision for Piperonyl Butoxide (PBO ).
United States Environ mental Protection Agency (USEPA). Prevention, Prsticides
and Toxic Substances. EPA 738

- R

- 06

- 005. June 2006. Available at http://www.epa.gov/oppsrrd1/reregistration/REDs/pi peronyl_red.pdf

. USEPA, 2006b. Revised Pyrethrins RED Chapter After Additional 60

- Day Comment Period, Phase 5. United States Environmental Protection Agency (USEPA). Prevention, Pesticides and Toxic Substances. June 2006.
USFWS/NMFS/NOAA.2004. 50 CFR Part 402. Joint Counterpart Endangered Species Act Section 7 Consultation Regulations; Final Rule. Federal Register Volume 69. Number 20.Pages 47731

- 47762. August 5, 2004 Weston, D.P., E.L. Amweg, A. Mekebri, R.S. Ogle and M.J. Lydy. 2006. Aquatic
Effec ts of Aerial Spraying for Mosquito Control over an Urban Area

. Environ.
Sci. Technol. 40, 5817

- 5822

. Williams, S., & Hogarth, W. 2004. Letter providing an evaluation by the U.S. Fish and Wildlife Service and National Marine Fisheries Service of an approach to assessing the ecological risks of pesticide products . Memorandum From to S. Hazen. January 26, 2004. United States Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS).

### 50

9. PRD data request justification tables

The fol lowing proposed Data Call

- in tables include rationales for requiring the data requested in this problem formulation, explanations of the utility of the data, and explanations for how the data might impact risk assessment, following the format provided by t he Pesticide Registration Division

.

Guideline Number: 835.4100 Study Title: Aerobic Soil Metabolism Rationale for Requiring the Data The Agency has a limited understanding of how PBO behaves in soil once applied. Depending on how quickly, to what exte nt, and to which transformation products the compound degrades, PBO may or may not pose potential exposure concern. Only one acceptable study (using one soil only) has been reviewed by the agency at this time (MRID# 43806401). This is a major deficiency and hinders our ability to determine 1) the pattern of PBO decline, 2) the patterns of formation and decline of the degradates, and 3)
an aerobic soil half life. The aerobic soil metabolism half

- life is a key input parameter in modeling drinking water as well as for ecological risk assessment. Practical Utility of the Data

How will the data be used? Additional aerobic soil metabolism data will facilitate a better understanding of the fate of PBO residues in soil. If data indicate that degradation in aer obic soil occurs rapidly and produces nontoxic transformation products, then the Agency could potentially determine that PBO residues of concern do not persist in soil under aerobic conditions. If data indicate that degradation is not appreciable in soil or that the transformation products are of similar or higher toxicity than the parent compound, then the Agency could conclude that PBO residues of concern persist in soil under some aerobic conditions.

How could the data change the Agency’s decision or impact the Agency’s future decision

- making? In the absence of the required data, PBO will be conservatively assumed to degrade in aerobic soils at a rate three times slower than the submitted data indicate. If the required data indicate that PBO in aero bic soils is rapidly biodegraded to nontoxic transformation products, then risk assessment conclusions and
associated labeled use precautions and/or restrictions could be made less restrictive.



### Guideline Number: 835.4300 Study Title: Aerobic Aquatic Met abolism Rationale for Requiring the Data The Agency has a limited understanding of how PBO behaves in aerobic aquatic environments once applied. The agency has only one upgradable to acceptable study using one sediment (MRID# 43836501). Depending on how quickly, to what extent, and to which transformation products the compound degrades, PBO may or may not pose potential exposure concern in water. As per OCSPP Harmonized Test Guidelines; At least two sediments and their associated waters are used for the aerobic aquatic metabolism study; aerobic surface water systems is not well understood, the Agency is requiring
data. Practical Utility of the Data

How will the data be used? Aerobic aquatic metabolism data will facilitate a better understanding of the fate of PBO residues in water. If data indicate that degradation in aerobic conditions occurs rapidly in aquatic systems and produces nontoxic transformation products, then the Agency could potentially determine that PBO residues of concern do not persist in these systems. If data indicate that degradation is not appreciable in aquatic systems or that the transformation products are of similar or higher toxicity than the parent

### 51

compound, then the Agency could conclude that PBO residues of concern persist in surficial aquatic systems under aerobic conditions.

How could the data change the Agency’s decision or impact the Agency’s future decision

- making? In the absence of the requested data, PBO will be assumed stable to biodegradation in aerobic, surfic ial aquatic environments. If the required data indicate that PBO in aerobic surficial aquatic environments is rapidly biodegraded to nontoxic degradation products, then risk assessment conclusions and associated labeled use precautions and/or restrictions could be made less restrictive.



### Guideline Number: 835.4400 Study Title: Anaerobic Aquatic Metabolism Rationale for Requiring the Data The Agency has a limited understanding of how PBO behaves in anaerobic aquatic environments once applied. The agenc y has only one supplemental study using one sediment (MRID# 43836501). Depending on how quickly, to what extent, and to which transformation products the compound degrades, PBO may or may not pose potential exposure concern in water. As per OCSPP Harmoniz ed Test Guidelines; At least two sediments and their associated waters are used for the anaerobic aquatic metabolism study; anaerobic surface water systems is not well understood, the Agency is requiring data. Practical Utility of the Data

How will the d ata be used? Anaerobic aquatic metabolism data will facilitate a better understanding of the fate of PBO residues in water. If data indicate that degradation in anaerobic conditions occurs rapidly in aquatic systems and produces nontoxic transformation pr oducts, then the Agency could potentially determine that PBO residues of concern do not persist in these systems. If data indicate that degradation is not appreciable in aquatic systems or that the transformation products are of similar or higher toxicity than the parent compound, then the Agency could conclude that PBO residues of concern persist in surficial aquatic systems under anaerobic conditions.

How could the data change the Agency’s decision or impact the Agency’s future decision

- making?

In t he absence of the requested data, PBO will be assumed stable to biodegradation in anaerobic, surficial aquatic environments. If the required data indicate that PBO in anaerobic surficial aquatic environments is rapidly biodegraded to nontoxic degradation products, then risk assessment conclusions and associated labeled use precautions and/or restrictions could be made less restrictive.



### Guideline Number: 835.1230 Study Title: Adsorption/Desorption Rationale for Requiring the Data

The Agency has a limite d understanding of PBO behaves in the environment once applied. Depending on the mobility of the compound in the environment, PBO may or may not be transported to surface water and/or ground water bodies used by organisms in the environment and/or by huma ns for drinking water. Unaged soil column data are available from one acceptable study (MRID# 43673801). As per OCSPP Harmonized Test Guidelines; At least two soils should be used to fulfill this guideline requirment. Because PBO mobility in the environmen t is not well understood, the Agency is requiring additional batch equilibrium data. Practical Utility of the Data

How will the data be used? Batch equilibrium data at concentrations resulting from labeled application rates will facilitate a better
under standing of PBO mobility in the environment. If data confirm that the compound has low mobility at these concentrations, then the Agency could potentially determine that PBO would not likely contribute to

### 52

environmental exposure. If data indicate that the compound is mobile at concentrations resulting from labeled application rates, then the Agency could not necessarily conclude that environmental exposure is negligible and further study and/or restrictions would be required.

How could the data impact t he Agency’s future decision

- making? In the absence of the required data, data from the open literature based on high concentrations will be used for ecological risk and drinking water exposure assessment. If the required data indicate that PBO is
mobile in the environment at concentrations resulting from labeled application rates, then environmental exposure may be of concern and additional use precautions and/or restrictions may be necessary.

Guideline Number: 8 75

. 210 0 Study Title : 

### Dislodgable Foliar Residues (modified for total foliar residue)

– protocol to be submitted prior to study initiation Rationale for Requiring the Data

The Agency has a limited understanding of PBO behaves in the environment once applied. This includes
foliar residues and foliar dissipation half

- lives for PBO and its three major degradates, PBO

- alcohol, PBO

aldehyde and PBO

- acid. Previous risk assessment shows a potential for chronic risk to mammals and birds from PBO using the default half

- life of 35 days.

Practical Ut ility of the Data
How will the data be used? Foliar dissipation rate data will be used to estimate the risk to terrestrial animals feeding on plants that have been exposed to PBO and its degradates through registered use.

How could the data impact the A gency’s future decision

- making? Without this information, the Agency will assume a default 35

- d dissipation rate, possibly overestimating or underestimating risk.

Guideline Number: 835.6100 Study Title: Analytical Method (and Associated Independent Lab oratory Validation) for Residues
in Soil and Sediment Rationale for Requiring the Data Independently validated analytical methods for residues in soil, water, sediment, and plant material (environmental chemistry methods) submitted by the registrant are used to evaluate analyses described in submitted environmental fate and ecological effects studies. Submitted analytical methods are also used by various Federal, State, Tribal, and local agencies to detect and monitor residues that are or are suspected t o be in environmental compartments due to outdoor uses and accidental releases. Independent laboratory validations for submitted analytical methods are necessary to confirm that the methods are functional and to confirm the levels of detection and quantit ation reported in registrant

- prepared
validations.

E nvironmental chemistry method s in soil or sediment have not been submitted in support of submitted
terrestrial or aquatic field dissipation studies of piperonyl butoxide (PBO) . An independently validate d environmental chemistry method in soil (and in sediment if procedures for sediment differ from those for soil) is n ecessary to evaluate the results of submitted ter restrial field dissipation studies and to provide outside agencies an analytical method wi th which to monitor for PBO residues in soil and aquatic
sediment

.

The submitted environmental chemistry method should include as analytes PBO and its major transformation products identified in laboratory environmental fate studies, which currently inclu de PBO

alcohol, PBO

- aldehyde

, and PBO

- acid . The level of quantitation (LOQ) should be below concentrations

### 53

that result in potential risks to benthos ( i.e. , should be less than the lowest toxicological level of concern with respect to benthos for PBO alone and for PBO plus the most toxic chemical with which it is co

applied). This LOQ will likely depend on the lowest toxicological level of concern for the most toxic co

applied chemical and the ratio of PBO to this chemical at which PBO is most synergistic with it

. Therefore, development of this environmental chemistry method should pend the results of the called

- in data in order to include as analytes all major transformation products identified in the submitted and
called

- in environmental fate studies and to include levels of quantitation below toxicological levels of
concern determined in the submitted and called

- in ecotoxicity studies, including the called

- in synergism
studies.
Practical Utility of the Data

How will the data be used?
In the absence of an independently validated environmental chemistry method in soil and sediment

, submitted ter restrial field dissipation studies are not acceptable and entities outside the Agency may lack
a chemical

- specific method for analyses in soil and sediment . An in dependently validated environmental chemistry meth od will be used to evaluate submitted ter restrial field dissipation studies in which it is used and will be made available for enforcement and monitoring purposes at the federal, state, and local levels.

H ow could the data change the Agency’s decision or impact the Agency’s future decision

- making? Risk assessment conclusions could be altered if they are not supported by either study data or environmental monitoring detections that are based on independent ly validated environmental chemistry methods. Furthermore, while not directly related to Agency decision

- making, independently validated environmental chemistry methods are necessary to ensure the safety of those in proximity to releases of
PBO and co

- app lied chemicals in the environment.

Guideline Number: 835.6200 Study Title: Analytical Method (and Associated Independent Laboratory Validation) for Residues
in Water Rationale for Requiring the Data Independently validated analytical methods for residu es in soil, water, sediment, and plant material (environmental chemistry methods) submitted by the registrant are used to evaluate analyses described in submitted environmental fate and ecological effects studies. Submitted analytical methods are also use d by various Federal, State, Tribal, and local agencies to detect and monitor residues that are or are suspected to be in environmental compartments due to outdoor uses and accidental releases. Independent laboratory validations for submitted analytical m ethods are necessary to confirm that the methods are functional and to confirm the levels of detection and quantitation reported in registrant

- prepared
validations.

Use of piperonyl butoxide (PBO) may impact surface water quality due to drift of residues and to runoff
of rain water carrying dissolved residues and residues adsorbed to suspended sediment

. PBO residues have a high potential for reaching surface water via runoff for several week s after application. Therefore, outside agencies may request ana lytical methods with which to monitor for PBO residues in water.

E nvironmental chemistry method s in water have not been submitted in support of submitted aquatic field dissipation studies. An independently validated enviro nmental chemistry method in wate r is n ecessary to evaluate the results of submitted aquatic field dissipation studies and to provide outside agencies an analytical method with which to monitor for PBO residues in water

.

The submitted environmental chemistry method should include as anal ytes PBO and its major transformation products identified in laboratory environmental fate studies, which currently include PBO

alcohol, PBO

- aldehyde

, and PBO

- acid . The level of quantitation (LOQ) should be below concentrations

### 54

that result in potential ri sks to aquatic organisms ( i.e. , should be less than the lowest toxicological level of concern with respect to aquatic organisms for PBO alone and for PBO plus the most toxic chemical with
which it is co

- applied). This LOQ will likely depend on the lowest toxicological level of concern for the
most toxic co

- applied chemical and the ratio of PBO to this chemical at which PBO is most synergistic
with it

. Therefore, development of this environmental chemistry method should pend the results of the
called

- in da ta in order to include as analytes all major transformation products identified in the submitted
and called

- in environmental fate studies and to include levels of quantitation below toxicological levels of
concern determined in the submitted and called

- in ecotoxicity studies, including the called

- in synergism
studies.

Practical Utility of the Data

How will the data be used?
In the absence of an independently validated environmental chemistry method in water, submitted aquatic field dissipation studies are not acceptable and entities outside the Agency may lack chemical

- specific methods for analyses in water

. An i ndependently validated environmental chemistry method will be used
to evaluate submitted aquatic field dissipation studies in which it is used an d will be made available for enforcement and monitoring purposes at the federal, state, and local levels.

How could the data change the Agency’s decision or impact the Agency’s future decision

- making? Risk assessment conclusions could be altered if they are not supported by either study data or environmental monitoring detections that are based on independently validated environmental chemistry methods. Furthermore, while not directly related to Agency decision

- making, independently validated
environmen tal chemistry methods are necessary to ensure the safety of those in proximity to releases of
PBO and co

- applied chemicals in the environment.

Guideline Number: 850.1075 Study Title: Fish Acute Toxicity Test, Freshwater TEP Rationale for Requiring the Data
PBO may be applied directly to water. Therefore, testing of a TEP applied to water is required to evaluate the potential effects of the ingredients within the TEP on fish.

Without toxicity data on the range of TEPs produced, the Agency would presume acute risk to
listed and non

- listed fish exceeds LOCs, but would not be able to quantify the risk and would not be able to evaluate efficacy of mitigations. Practical Utility of the Data
How will the data be used? Toxicity data with at least one TEP and a bridging strategy to others would allow the Agency to further analyze potential acute effects. The effects data would be used to determine the likelihood that acute risks can potentially impact aquatic communities, either by
direct effects on f

ish or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity concerns with PBO use.

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that PBO products "may affect" endangered fish directly (and endangered species f rom other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endang ered Species Act and could result in use restrictions for PBO products which are unnecessarily severe.

### 55

Guideline Number: 850.1075 Study Title: Fish Acute Toxicity Test, Freshwater using PBO

- alcohol Rationale for Requiring the Data
PBO may be applied directly to water. Since PBO

- alcohol has a similar structure, it is expected to have similar piscicidal properties. 

### Without toxicity data on degradates, the Agency will assess risks using a strategy of total toxic residues.

Practical Utility of the Dat a How will the data be used? Toxicity data on major degradates would allow the Agency to further analyze potential acute effects. The effects data would be used to determine the likelihood that acute risks can potentially impact aquatic communities, eit her by direct effects on fish or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be
able to determine whether any mitigation imposed as part of the registration review process i s appropriate due to toxicity concerns with PBO use.

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that PBO

alcohol is at least as toxic as PBO or that PBO products "may affect" endangered fish directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO products which are unnecessarily severe.

Guideline Number: 850.1075 Study Title: Fish Acute Toxicity Test, Freshwate r using PBO

- aldehyde Rationale for Requiring the Data
PBO may be applied directly to water. Since PBO

- aldehyde has a similar structure, it is expected to have similar piscicidal properties. 

### Without toxicity data on degradates, the Agency will
assess ris ks using a strategy of total toxic residues.

Practical Utility of the Data
How will the data be used? Toxicity data on major degradates would allow the Agency to further analyze potential acute effects. The effects data would be used to determine the likelihood that acute risks can potentially impact aquatic communities, either by direct effects on fish or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be
able to determine whether any mitigation impose d as part of the registration review process i s appropriate due to toxicity concerns with PBO use.

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without these data, the Agency wo uld have to assume that PBO

aldehyde is at least as toxic as PBO or that PBO products "may affect" endangered fish directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered s pecies could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO products which are unnecessarily severe.

Gu ideline Number: 850.1075 Study Title: Fish Acute Toxicity Test, Freshwater using PBO

- acid

### 56

Rationale for Requiring the Data
PBO may be applied directly to water. Since PBO

- acid has a similar structure, it is expected to have similar piscicidal propert ies. 

### Without toxicity data on degradates, the Agency will assess risks using a strategy of total toxic residues.

Practical Utility of the Data
How will the data be used? Toxicity data on major degradates would allow the Agency to further analyze potent ial acute effects. The effects data would be used to determine the likelihood that acute risks can potentially impact aquatic communities, either by direct effects on fish or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be
able to determine whether any mitigation imposed as part of the registration review process i s appropriate due to toxicity concerns with PBO use.

How could the data impact the Agency’s future decision

- making? If future endangered spec ies risk assessments are performed without these data, the Agency would have to assume that PBO

acid is at least as toxic as PBO or that PBO products "may affect" endangered fish directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use re strictions for PBO products which are unnecessarily severe.

### 57

Guideline Number: 850 .1075 Study Title: Fish Acute Toxicity Test, Freshwater (Modified Guideline Study designed to evaluate synergism) Rationale for Requiring the Data
PBO and its major degradates are persistent, mobile and may pass through wastewater treatment

processes. It may also be applied directly to water. PBO is a pesticide synergist. Therefore, it is used in combination with other pesticides to enhance their effectiveness (tox icity) to target organisms. Assessing potential ecological risks of PBO requires evaluating potential exposure and toxicity of the active ingredient (PBO alone) and evaluating the enhanced toxicity of other pesticides with which it is simultaneously appli ed. Given the number of chemicals with which PBO may be simultaneously applied, designing a study that examines the range of synergistic effects is difficult. A comprehensive evaluation of potential synergistic effects of PBO and all
chemical s with which it may be simultaneously applied will require the development and review of a large body of data. The Agency recognizes that this data set is extensive and is willing to consider options for a reduced data set that evaluates the nature of PBO synergy with a limited number of compounds, and allows bridging to these more extensive synergy studies from reduced

data sets for other chemicals. 

### The goal of obtaining this set of data is to determine the potential range of magnitudes of synergistic effects for pes ticide active ingredients that are

co

- applied with PBO for the purpose of enhancing efficacy due to synergism. The Agency is interested in obtaining data on (or bridging data to) pesticide active ingredients (in addition to other chemicals with similar mo des of action) that are co

- applied with PBO for its synergistic properties including those that are formulated with PBO and those that are otherwise recommended for mixing with PBO prior to application.

Protocols need to be submitted to the Agency prior to study initiation.

Without toxicity data on the range of TEPs produced, the Agency would presume acute risk to
listed and non

- listed fish and aquatic

- phase amphibians exceeds LOCs, but would not be able to quantify the risk and would not be able to eva luate efficacy of mitigations. Practical Utility of the Data
How will the data be used? Toxicity data with at least one TEP and a bridging strategy to others would allow the Agency to further analyze potential acute effects. The effects data would be u sed
to determine the likelihood that acute risks can potentially impact aquatic communities, either by
direct effects on fish and aquatic

- phase amphibians or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity
concerns with PBO use

.

How could the data impact the Agency’s future decision

- making? If future endangered species
risk assessme nts are performed without these data, the Agency would have to assume that PBO products "may affect" endangered fish and aquatic

- phase amphibians directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restric ted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and
could result in use restrictions for PBO products which are unnecessarily severe.

### 58

Guideline Number: 850.1400 Study Title: Fish Early Life Stage (Saltwater) Rationale for Requiring the Data
The acute toxicity of PBO to estuarine/marine fish and environmental fate properties indicate the potential for

c hronic exposure and effects to animals in this taxon, per 40 CFR Part 158 data requirements (October 26, 2007). For example, the acute LC 50 for oysters (0.23 mg a.i./L) is below 1.0 mg/L and the estimated peak EECs (58

- 160 ppb for aerieal applications to s everal crops) exceed 0.01 of the acute toxicity value for sheepshead (39.4 ppb), both criteria specified in 40 CFR Part 158 for conditionally requiring this study. Furthermore, the persistence of PBO in water is expected to substantially exceed the 4

- d ha lf life criterion specified in 40 CFR
Part 158. Practical Utility of the Data

How will the data be used? The estuarine/ marine fish early life stage study would allow the Agency to analyze chronic effects, including effects on reproductive success and growth, to saltwater species. The effects data would be used to determine the likelihood that the chronic risks can potentially impact aquatic communities, either by direct effects on fish or by indirect effects by reducing their food sources. By refinin g the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity concerns with PBO.

How could the data impact the Agency’s future decision

- making?
If future e ndangered species risk assessments are performed without these data, the Agency would have to assume that PBO "may affect" endangered estuarine/ marine fish directly (and endangered species from other taxa indirectly), and use of PBO might need to be restr icted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO which are un necessarily severe.

Guideline Number: 850. 1500 Study Title: Fish Full Life

- cycle Test (Freshwater) Rationale for Requiring the Data

The acute toxicity of PBO to fish and environmental fate properties indicate the potential for chronic exposure

an d effects to animals in this taxon, per 40 CFR Part 158 data requirements (October 26, 2007). Expected EECs exceed the early life stage NOAEC of 40 ug/L for a number of uses. A life

- cycle study is triggered if expected
environmental concentrations exceed 1/10 th the early

- life stage NOAEC. Based on the early life stage study in freshwater fish, Furthermore, the persistence of PBO in water is expected to substantially exceed the 4

- d half life criterion specified in 40 CFR Part 158.

The preferred test spec ies would be the rainbow trout since acute data are available on this species. If another species is chosen, for which EPA does not have acute data, acute data will also be needed on that species. Practical Utility of the Data

How will the data be used?
The f ull life

- cycle study would allow the Agency to analyze chronic effects, including effects on reproductive success and growth. The effects data would be used to determine the likelihood that the chronic risks can potentially impact aquatic communit ies, either by direct effects on fish and aquatic

- phase amphibians or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review p rocess was appropriate due to toxicity concerns with PBO.

### 59

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that PBO "may affect" endangered fish and aquatic

- phase amphibians directly (and endangered species from other taxa indirectly), and use of PBO might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO which are unnecessarily severe.

Guideline Numbers: 850.1770 Study Title: Chronic whole sediment: Freshwater Hylella

Rat ionale for Requiring the Data Available information indicates that benthic organisms may be exposed via run

- off or spray drift applications used in agricultural, forest, and residential settings , or by direct application to water.
Chronic sediment toxic ity tests are required to satisfy the Agency‟s updated data requirements for
outdoor uses in 40 CFR Part 158 (October 26, 2007). Specifically, PBO has a half

- life of 14d in aerobic soil and 75d in aerobic water (MRIDs 43806401 and 43803401 both as amended
5/17/2004 ), a log Kow of 4.75 and Koc of up to1152 (MRID 43673802 ) and expected peak EECs (58 to 160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 15 ) which exceed 0.1 of the
acute LC/EC 50 (490*0.1 = 49 ppb for M. bahia, MRID 43901801). The criteria are, therefore, met for requiring chronic sediment toxicity studies.

Finally, the potential for persistent exposure from PBO in sediment is also indi cated by open literature studies on pyrethroids (Weston et al. 2005, Amweg et al. 2006 and Ding et al. 2009).

For sediment studies involving pyrethroids, chronic tests on Hyalella azteca

, Chironomus tentans

, and Leptocheirus plumulosus are requested. Al though both Hyalella and Chironomus are both freshwater species, they differ substantially in their ecological niche ( i.e. , epibenthic vs. infaunal), physiology, and potential sensitivities to pyrethroid exposure. PBO has the potential to enter
estuarine/ marine water bodies based on current usuage patterns that include coastal areas. Therefore, testing is required for Leptocheirus plumulosus , an estuarine/marine sediment

- dwelling invertebrate species. Practical Utility of the Data

How will the data be us ed? Data from sediment toxicity studies will be used to estimate potential risks to benthic organisms
associated with uses of PBO. The data will reduce uncertainties associated with the current risk assessment for benthic species and will improve our und erstanding of the potential effects of
PBO.

How could the data impact the Agency’s future decision

- making? Acceptable data for benthic organisms will reduce the uncertainty from previous assessment s. Since potential risk was found for adverse effects t o other aquatic organisms , a cceptable data for benthic organisms will reduce the uncertainty from the previous assessment

. If the data indicate that registered PBO usage may pose a risk of adverse effects to non

- target benthic organisms above the Agency L evel of Concern, the Agency may explore decision options to mitigate this risk. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act, and could result in use restrictio ns for PBO which may otherwise be avoided, or which are unnecessarily severe.

15 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 60

Guideline Numbers: 850.1760 Study Title: Chronic whole sediment: Freshwater chironimid Rationale for Requiring the Data Available information indicates that benthic organ isms may be exposed via run

- off or spray drift applications used in agricultural, forest, and residential settings, or by direct application to water. Chronic sediment toxicity tests are required to satisfy the Agency‟s updated data requirements for

outd oor uses in 40 CFR Part 158 (October 26, 2007). Specifically, PBO has a half

- life of 14d in aerobic soil and 75d in aerobic water (MRIDs 43806401 and 43803401 both as amended 5/17/2004), a log Kow of 4.75 and Koc of up to1152 (MRID 43673802, also see Tabl e 3 ). Estimated EECs can exceed 0.1 of the acute toxicity LC/EC 50 for mysids (see Freshwater Fish section above). The criteria are, therefore, met for requiring chronic sediment toxicity studies.

Finally, the potential for persistent exposure from PBO in sediment is also indicated by open literature studies on pyrethroids (Weston et al. 2005, Amweg et al. 2006 and Ding et al. 2009).

For sediment studies involving pyrethroids, chronic tests on Hyalella azteca

, Chironomus tentans

, and Leptocheirus plum ulosus are requested. Although both Hyalella and Chironomus are both freshwater species, they differ substantially in their ecological niche ( i.e. , epibenthic vs. infaunal), physiology, and potential sensitivities to pyrethroid exposure. PBO has the pote ntial to enter estuarine/marine water bodies based on current usuage patterns that include coastal areas. Therefore, testing is required for Leptocheirus plumulosus , an estuarine/marine sediment

- dwelling invertebrate species.

In addition, depending on the results of the fish and invertebrate special studies designed to evaluate synergism, the study design of this sediment toxicity study may need to be modified to address synergistic effects of pesticides applied simultaneously with PBO.

Practical Utilit y of the Data

How will the data be used? Data from sediment toxicity studies will be used to estimate potential risks to benthic organisms
associated with uses of PBO. The data will reduce uncertainties associated with the current risk
assessment for be nthic species and will improve our understanding of the potential effects of
PBO.

How could the data impact the Agency’s future decision

- making? Acceptable data for benthic organisms will reduce the uncertainty from previous assessments. Since potentia l risk was found for adverse effects to other aquatic organisms, acceptable data for benthic organisms will reduce the uncertainty from the previous assessment If the data indicate that registered PBO usage may pose a risk of adverse effects to non

- target benthic organisms above the Agency Level of Concern, the Agency may explore decision options to mitigate this risk. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Ac t, and could result in use restrictions for PBO which may otherwise be avoided, or which are unnecessarily severe.

### 61

Guideline Numbers: 850.1780 Study Title: Chronic whole sediment: Marine invertebrates Rationale for Requiring the Data

Available i nformation indicates that benthic organisms may be exposed via run

- off or spray drift applications used in agricultural, forest, and residential settings, or by direct application to water. Chronic sediment toxicity tests are required to satisfy the Agen cy‟s updated data requirements for outdoor uses in 40 CFR Part 158 (October 26, 2007). Specifically, PBO has a half

- life of 14d in aerobic soil and 75d in aerobic water (MRIDs 43806401 and 43803401 both as amended 5/17/2004), a log Kow of 4.75 and Koc of up to1152 (MRID 43673802, also see Table 3 ). Estimated EECs can exceed 0.1 of the acute toxicity LC/EC 50 for mysids (see Freshwater Fish section above). The criteria are, therefore, met for requiring chronic sediment toxicity studies.

Finally, the pot ential for persistent exposure from PBO in sediment is also indicated by open literature studies on pyrethroids (Weston et al. 2005, Amweg et al. 2006 and Ding et al. 2009).

For sediment studies involving pyrethroids, chronic tests on Hyalella azteca

, Ch ironomus tentans

, and Leptocheirus plumulosus are requested. Although both Hyalella and Chironomus are both freshwater species, they differ substantially in their ecological niche ( i.e. , epibenthic vs. infaunal), physiology, and potential sensitivities to pyrethroid exposure. PBO has the potential to enter estuarine/marine water bodies based on current usuage patterns that include coastal areas. Therefore, testing is required for Leptocheirus plumulosus , an estuarine/marine sediment

- dwelling
invertebrate species. Practical Utility of the Data

How will the data be used? Data from sediment toxicity studies will be used to estimate potential risks to benthic organisms
associated with uses of PBO. The data will reduce uncertainties associated with the curr ent risk assessment for benthic species and improve our understanding of the potential effects of PBO.

How could the data impact the Agency’s future decision

- making? Acceptable data for benthic organisms will reduce the uncertainty from previous assessme nts. Since potential risk was found for adverse effects to other aquatic organisms, acceptable data for benthic organisms will reduce the uncertainty from the previous assessment If the data indicate that registered PBO usage may pose a risk of adverse effects to non

- target benthic organisms above the Agency Level of Concern, the Agency may explore decision options to mitigate this risk. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act, and could result in use restrictions for PBO which may otherwise be avoided, or which are unnecessarily severe.

### 62

Guideline Number: 850.1010 Study Title: Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids, TEP

Rat ionale for Requiring the Data
PBO may be applied directly to water. Therefore, testing of a TEP applied to water is required to evaluate the potential effects of the ingredients within the TEP on fish.

Without toxicity data on the range of TEPs produc ed, the Agency would presume acute risk to
listed and non

- listed fish exceeds LOCs, but would not be able to quantify the risk and would not be able to evaluate efficacy of mitigations. Practical Utility of the Data
How will the data be used? Toxicity d ata with at least one TEP and a bridging strategy to others would allow the Agency to further analyze potential acute effects. The effects data would be used to determine the likelihood that acute risks can potentially impact aquatic communities, either b y direct effects on fish or by indirect effects by reducing their food sources. By refining the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity con cerns with PBO use.

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that PBO products "may affect" endangered fish directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compl iance with the Endangered Species Act and could result in use restrictions for PBO products which are unnecessarily severe.

### 63

Guideline Number: 850.1010 Study Title: Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids (modified guideline stu dy to evaluate synergism) Rationale for Requiring the Data
PBO and its major degradates are persistent, mobile and may pass through wastewater treatment

processes. PBO is a pesticide synergist. Therefore, it is used in combination with other pesticide s to enhance their effectiveness (toxicity) to target organisms. Assessing potential ecological risks of PBO requires evaluating potential exposure and toxicity of the active ingredient (PBO alone) and evaluating the enhanced toxicity of other pesticides with which it is simultaneously applied. Given the number of chemicals with which PBO may be simultaneously applied, designing a study that examines the range of synergistic effects is difficult. A comprehensive evaluation of potential synergistic effect s of PBO and all chemical with which it may be simultaneously applied will require the development and review of a large body of data. The Agency recognizes that this data set is extensive and is willing to consider options for a
reduced data set that eval uates the nature of PBO synergy with a limited number of compounds, and allows bridging to these more extensive synergy studies from reduced data sets for other

chemicals. 

### The goal of obtaining this set of data is to determine the potential range of magni tudes of synergistic effects for pesticide active ingredients that are co

- applied with PBO for the purpose of enhancing efficacy due to synergism. The Agency is interested in obtaining data on (or bridging data to) pesticide active ingredients (in additio n to other chemicals with similar modes of action) that are co

- applied with PBO for its synergistic properties including those that are formulated with PBO and those that are otherwise recommended for mixing with PBO prior to application.

Protocols need to be submitted to the Agency prior to study initiation.

Without toxicity data on the range of TEPs produced, the Agency woud have to presume acute toxicity to listed and non

- listed fish and aquatic

- phase amphibians , but would not be able to quantify the risk or effectiveness of potential mitigations.

Practical Utility of the Data
How will the data be used? Toxicity data with at least one TEP and a bridging strategy to others would allow the Agency to further analyze potential acute effects. The effe cts data would be used
to determine the likelihood that acute risks can potentially impact aquatic communities, either by
direct effects on fish and aquatic

- phase amphibians or by indirect effects by reducing their food sources. By refining the assessment , the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity
concerns with PBO use

.

How could the data impact the Agency’s future decision

- making? If future endangered sp ecies risk assessments are performed without these data, the Agency would have to assume that PBO products "may affect" endangered fish and aquatic

- phase amphibians directly (and endangered species from other taxa indirectly), and use of PBO products might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and
could result in use restrictions for PBO products which are unnecessarily severe.

### 64

Guideline Number: 850.1 350 Study Title: Aquatic Invertebrate Life

- cycle Toxicity (Saltwater) Rationale for Requiring the Data
PBO and its major degradates are persistent, mobile and may pass through wa stewater treatment

processes. Chronic toxicity data are required per 40 CFR Part 158.630 due to the potential for direct application of PBO to the estuarine/marine environment, acute toxicity value that is <1 ppm (0.23 for the oyster), and the expected pe ak EECs (58 to 160 ppb, for aerial application to lettuce, cabbage, citrus, cucumber, pepper, strawberry, potato, tomato, beans, sugarbeets and cotton, 2005 RED eco chapter 16 ) exceed 0.01 of the acute toxicity values (this would be 4.9 ppb for mysid and

2. 3 ppb for oysters). This requirement is based on PBO use in a variety of products applied directly to water and used in agriculture. Practical Utility of the Data
How will the data be used? The full life

- cycle study would allow the Agency to further a nalyze potential chronic effects. The effects data would be used to determine the likelihood that the chronic risks can potentially impact aquatic communities, either by direct effects on fish or by indirect effects by reducing their food sources. By ref ining the assessment, the Agency would be able to determine whether the mitigation imposed as part of the registration review process was appropriate due to toxicity concerns with PBO.

How could the data impact the Agency’s future decision

- making? If futu re endangered species risk assessments are performed without these data, the Agency would have to assume that PBO "may affect" endangered fish directly (and endangered species from other taxa indirectly), and use of PBO might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO which are unnecessarily se vere.

Guideline Number: 850.4400 Study Title: Aquatic Vascular Plant Growth

- Tiers I/II Rationale for Requiring the Data No acceptable studies for PBO have been submitted for vascular aquatic plants. The Agency has finalized its update to the data req uirements in 40 CFR Part 158. In these updated data requirements, which were promulgated on October 26, 2007, vascular plant testing is required for pesticides such as PBO with outdoor uses. Tier I testing is required, followed by Tier II if required by Tier I results as specified in Tier I guidelines. Practical Utility of the Data

How will the data be used? Data from aquatic plant toxicity studies will be used to estimate potential risks to plants
associated with uses of PBO. The data will reduce unce rtainties associated with the current risk assessment for aquatic plants and will improve our understanding of the potential effects on vascular aquatic plants.

How could the data change the Agency’s decision, or impact the Agency’s future decision

makin g? Because plants form the basis of most habitats and significantly contribute to overall environmental quality, a solid understanding of the potential risks to aquatic plants is essential for sound environmental management. Without plant growth data fo r PBO, the Agency cannot

16 P iperonyl B utoxide: Environmental Risk Assessment , Revised September, 2005. D139408.

### 65

determine the levels of PBO that result in effects to vascular aquatic plants

. If the data indicates that registered PBO usage may pose a risk of adverse effects to non

- target aquatic vascular plants above the Agency Level of Conc ern, the Agency may explore decision options to mitigate
this risk.

If future endangered species risk assessments are performed without these data, the Agency would have to assume that PBO "may affect" endangered plants and use of PBO might need to
be r estricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO that may be unnecessarily

severe.

Guideline Number: 850.5400 Study Title: Algal toxicity test

, Tier I/II Rationale for Requiring the Data No toxicity data are currently available to assess the risk of PBO to aquatic nonvascular plants.
Since PBO has resid ential outdoor uses, Tier I/II aquatic nonvascular plant studies are required. These phytotoxicity data are needed to evaluate the level of pesticide exposure to non

- target aquatic plants and to assess the impact of pesticides on endangered and threatened plants. T he Agency updated its data requirements in 40 CFR Part 158 (October 26, 2007) to include plant
studies . Tier I testing is required, followed by Tier II if required by Tier I results as specified in Tier I guidelines. Practical Utility of the D ata
How will the data be used? Data from Tier I/II nonvascular aquatic plant toxicity studies will be used to estimate potential risks to plants associated with uses of PBO. The data will reduce uncertainties associated with the
current risk assessment for nonvascular aquatic plants and will improve our understanding of the potential effects of PBO.

How could the data impact the Agency’s future decision

- making? Because plants form the basis of most habitats and significantly contribute to overall
envi ronmental quality, a solid understanding of the potential risks to nonvascular aquatic plants is essential for sound environmental management. Without plant growth data for PBO, the Agency
cannot determine the levels that result in effects to aquatic plan ts

. If the data indicates that registered usage may pose a risk of adverse effects to non

- target aquatic nonvascular plants above the Agency Level of Concern, the Agency may explore decision options to mitigate this risk. T he
lack of these data will limi t the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act, and could result in use restrictions for PBO which may otherwise be avoided, or which are unnecessarily severe.

Guideline Number: 850.3020
St udy Title: Honey Bee Acute Contact Toxicity Test using TEP Rationale for Requiring the Data Terrestrial invertebrate toxicity data are required to quantitatively assess the potential impacts on this group of organisms. Data are needed from the honey be e acute contact study due to wide spread use and possible drift to off site vegetation in bloom. Available data (MRID 41969009) show PBO to be moderately toxic to practically non

- toxic to honey bees (LD 50

> 25 μg/bee). Since PBO acts as a synergist insecticide, the effects of a typical end

- use product (TEP) may be much greater.

### 66 Practical Utility of the Data
How will the data be used? The honeybee study using TEP would allow the Agency to analyze pollin ators and other non

- target terrestrial insects . The effects data would be used to determine the likelihood that the risks can potentially impact terrestrial invertebrate communities. By refining the assessment, the Agency would be able to determine wheth er the mitigation imposed as part of the registration review process was appropriate due to toxicity concerns with PBO.

How could the data impact the Agency’s future decision

- making? If future endangered species risk assessments are performed without thes e data, the Agency would have to assume that PBO

TEPs "may affect" endangered terrestrial insects directly (and endangered species from other taxa indirectly), and use of PBO might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for PBO which are unnecessarily severe.

Guideline Numbers: 850. 41 0 0 and 850. 41 5 0 Study Title: Vegetative vigor and Seedling emergence with TEP, Tier I/Tier II
Rationale for Requiring the Data No acceptable toxicity data are currently available to assess the risk of PBO to terrestrial plants.

T he Agency updated its data requir ements in 40 CFR Part 158 (October 26, 2007) to include plant studies.

Since PBO has residential outdoor uses, vegetative vigor and seedling emergence studies using TEP are required. These phytotoxicity data are needed to evaluate the level of pesticide
exposure to non

- target terrestrial and aquatic plants and to assess the impact of pesticides on endangered and threatened plants. Tier I testing is required, followed by Tier II if required by Tier I results as specified in Tier I guidelines.

Practical U tility of the Data

How will the data be used? Data from terrestrial plant toxicity studies will be used to estimate potential risks to plants
associated with uses of PBO. The data will reduce uncertainties associated with the current risk
assessment fo r terrestrial plants and will improve our understanding of the potential effects of
PBO on plants.

How could the data impact the Agency’s future decision

- making? Because plants form the basis of most habitats and significantly contribute to overall
envir onmental quality, a solid understanding of the potential risks to terrestrial plants is essential for sound environmental management. Without acceptable plant growth data for PBO, the Agency cannot determine the levels of PBO that result in effects to ter restrial plants

. If the data indicates that registered PBO usage may pose a risk of adverse effects to non

- target terrestrial plants plants above the Agency Level of Concern, the Agency may explore decision options to mitigate this risk. T he lack of thes e data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act, and could result in use restrictions for PBO which may otherwise be avoided, or which are unnecessarily severe.

### 67

Guideline Num ber: 850.2100 Study Title: Avian Acute Oral Toxicity Test Rationale for Requiring the Data Acceptable acute avian oral toxicity data were not submitted for a passerine species exposed to PBO, which is now required under the 40 CFR Part 158 (CFR 40 200 8) data requirements for conventional pesticides. The revised Part 158 data requirements specify that acute avian oral toxicity data be submitted for either one waterfowl or one upland game species and one passerine species. The available acute oral toxici ty data for mallard ducks and bobwhite quails, when compared to estimated environmental concentrations, indicate that levels of concern are not exceeded for birds on an acute basis. Many passerine species utilizing forests, residential areas and
surroundin g areas, have the potential to be exposed to pesticides used in agricultural, forest, and residential settings. It is likely that, for most pesticide use patterns, passerines are more likely to be exposed to pesticides than upland game species and waterfo wl. Because passerine species have higher metabolic rates due to their smaller sizes than either waterfowl or upland game bird species and because they may utilize different metabolic pathways, they may be more or less sensitive to PBO. In order to proper ly characterize risk to passerines, an avian oral toxicity test is required for passerine birds. A passerine study protocol must be submitted for review by the Agency prior to initiation of the study. Practical Utility of the Data

How will the data be us ed? Acute avian oral toxicity data for passerine species will be used to refine the screening

- level risk assessment by determining whether there are differences in avian species sensitivity to PBO between currently tested passerine and upland game and/or w aterfowl species that are beyond the simple allometric predictions currently employed in the absence of such passerine data. The current extrapolation method may be under

- or over

- estimating risks to passerines.

How could the data impact the Agency’s futu re decision

- making? If future risk assessments, including listed species assessments, are performed without these data, the Agency would have to assume that PBO “may affect” listed birds directly (and listed species from other taxa indirectly), and use of PBO and its formulated products may need to be restricted in areas where listed species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in complying with the Endangered Species Act and could result in

res trictions for PBO use that might prove to be unnecessary given data to address this area of uncertainty.

Guideline Number: None Study Title: POTW Effluent Monitoring and POTW Treatability Study Rationale for Requiring the Data POTW Effluent Monitoring

– Request any existing or ongoing POTW effluent monitoring data for the pyrethroids be submitted to the Agency.

POTW Treatability Study

– In addition, the Agency is requiring a bench scale study of waste water treatment, to assess amounts that would degr ade during treatment, remain in the waste water, or partition to biosolids. Practical Utility of the Data

How will the data be used? These data would be used to inform removal percentages by waste water treatment, which is an input to the Exposure and F ate Assessment Screening Tool‟s ( E

- FAST) down

- the

- drain module.

### 68

Guideline Number: None Study Title: POTW Effluent Monitoring and POTW Treatability Study

How could the data impact the Agency’s future decision

- making? Without these data, the Agency will have to make assumptions regarding the level of removal of PBO ( e.g. , results of modeling f rom the EPIWEB v.4.0 may be used). Since the assumptions are likely to be crude and conservative. T he lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act, and could
resul t in use restrictions for PBO which may otherwise be avoided, or which are unnecessarily

severe.

### 69



## Appendix A: Uses of Piperonyl Butoxide Eligible for Reregistration Updated 9/23/10

A

- 1: Food/Feed Uses

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

AGRICULTURAL

Preharvest Application to Field, Orchard, and Greenhous e Food Crops

Crop Group 1: Root and Tuber Vegetables [including Arracacha; Arrowroot; Artichoke, Chinese; Artichoke, Jerusalem; Beet, garden, Beet, sugar; Burdock, edible; Canna edible; Carrot; Cassava; Celeriac; Chayote; Chervil, turnip

- rooted; Chicory ; Chufa; Dandelion; Dasheen; Ginger; Ginseng; Horseradish; Leren; Parsley, turnip

- rooted; Parsnip; Potato; Radish; Radish, Oriental; Rutabaga; Salsify; Salsify, black; Salsify, Spanish; Skirret; Sweet Potato; Tanier; Taro; Turmeric; Turnip; Yam bean; and Y am, true]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface applicat ion to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 2: Leaves of Root and Tuber Vegetables [including Beet, garden; Beet, sugar; Burdock, edible; Carro t; Cassava; Chervil, turnip

- rooted; Chicory; Dasheen; Parsnip; Radish; Radish, Oriental; Rutabaga; Salsify, black; Tanier; Taro; Turnip; and Yam, true]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme p est pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orc hard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 3: Bulb Vegetables [including Garlic; Garlic, great headed; Leek; Onion, dry bulb; Onion, green; Onion, potato; Onion, tree; Onion, welsh; and Shallot]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not re apply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

S pace application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

### 70

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Crop Group 4: Leafy Vegetables (Except Brassica Vegetables) [including Amaranth, leafy; Arugula; Cardoon; Celery; Celery, Chinese; Celtuce; Chervil; Chrysanthemum, edible

- leaved; Chry santhemum, garland; Corn salad; Cress, garden; Cress, upland; Dandelion; Dock; Endive; Fennel, Florence; Kale, sea; Lettuce, head; Lettuce, leaf; Orach; Parsley; Purslane, garden; Purslane, winter; Radicchio; Rhubarb; Spinach; Spinach, Chinese; Spinach, Ne w Zealand; Spinach, vine; Swiss chard; and Tampala]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours.
Do not harvest unti l spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 5: Brassica (Cole) Leafy Vegetables [including Broccoli; B roccoli, Chinese; Broccoli raab; Brussels sprouts; Cabbage; Cabbage, Chinese, Bok choy; Cabbage, Chinese, mustard; Cabbage, Chinese, napa; Cauliflower; Collards; Kale; Kohlrabi; Mustard greens; Mustard spinach; and Rape greens]

Application to outdoor gr owing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012
lb/1 ,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 6: Legume Vegetables (Succulent or Dried) [including Bean (adzuki, broad, dry, kidney, lablab, lima, moth, mung, navy, pink, pinto, rice, runner, snap, tepary, urd, wax, yardlong); Catjang; Chickpea; Cowpea; Guar; Gum, edible; Jackbean; Lentil; Lupin, grain; Pea (blackeyed, crowder, dry, dwarf, edible

- pod, English, field, garden, green, pigeon, snow, southern, succulent, sugar snap); Soybean ; and Swordbean]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applicati ons: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. For rice, a 10 day water hold is required for all applications when rice fields are flooded. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 7 : Foliage of Legume Vegetables [including Bean (dry, lima, snap); cowpea; Lupin, grain; Pea (field and pigeon); Soybean]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extre me pest pressure, do not reapply
within 24 hours. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

### 71

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0 Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants t o point of runoff or drip. Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

C rop Group 8: Fruiting Vegetables (Except Cucurbits) [including Chili; Eggplant; Groundcherry; Pepino; Pepper (bell, nonbell, nonbell sweet); Tomatillo; Tomato]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/ A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

gro wn crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 9: Cucurbit Vegetables [including Balsam apple; Balsam pear; Cantaloupe; Chayote; Cucumber; Cucumber, Chinese; Gherkin, West Indian; Gourd, edible; Melon; Melon, citron; Muskmelon; Pumpkin; Squash; Squash, summer; Squash, winter; Watermelon; Waxgourd, Chinese]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours.
Do not harvest un til spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

cro ps 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 10: Citrus Fruits (Citrus spp., Fortunella spp.) [includ ing Calamondin; Citron, citrus; Citrus; Citrus hybrids; Grapefruit; Kumquat; Lemon; Lime; Mandarin, satsuma; Orange, sour; Orange, sweet; Pummelo; Tangelo; Tangerine]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted sol ution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

Space application to greenho use

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 11: Pome Fruits [including Apple; Crabapple; Loquat; Mayhaw; Pear; Oriental Pear; and Quince]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pe st pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

### 72

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0 Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orcha rd

crops. Do not wet plants to point of runoff or drip. Space application to greenhouse

grown crop 0. 0014 lb/1,000 cu. ft 10 0

Crop Group 12: Stone Fruits [including Apricot; Cherry, sweet; Cherry, tart; Nectarine; Peach; Plum; Plum, chickasaw; Plum, damson; Plum, Japanese; and Plum, prune]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not re apply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Sp ace application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 13: Berries [including Blackberry, Blueberry; Currant; Elderberry; Gooseberry; Huckleberry; Loganberry; and Raspberry (black and red)]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 14: Tree Nuts [including Almond; Beech nut; Brazil nut; Butternut; Cashew; Chestnut; Chinquapin; Filbert; Hickory nut; Macadamia nut; Pecan; Pistachi o; Walnut, black; and Walnut, English]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dr ied. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

wa ter 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 15: Cereal Grains [including Barley; Buckwheat; Corn (field, pod, pop, and sweet); Millet; Millet, pearl; Millet, proso; Oat; Rice; Rice, wild; Rye; Sorghum, grain; Teosinte; Triticale; Wheat; Wheat, vavilovi; Wheat, wild einkorn; and Whea t, wild emmer]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply withi n 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

### 73

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0 Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal . of diluted solution/A to orchard

crops. For rice, a 10 day water hold is required for all applications when rice fields are flooded. Do not wet plants to point of runoff or drip. Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 16: Forage, Fodder, and Straw of Cereal Grains [including Barley; Corn (field, pod, pop, and sweet); Millet; Millet, pearl; Millet, proso; Oat; Rice; Rice, wild; Rye; Sorghum (forage and grain); Teosinte; Triticale; Wheat; Wheat, vavi lovi; Wheat, wild einkorn; and Wheat, wild emmer]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not r eapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. For rice, a 10 day water hold is required for all applications when rice fields are flooded. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 17: Grass Forage, Fodder, and Hay [including Alkali sacaton; Alkaligrass; Ariz ona cottontop; Bahiagrass; Beachgrass; Bentgrass; Bentgrass, spike; Bermudagrass; Blowoutgrass; Bluegrass; Bluegrass, silky; Bluestem australian; Bluestem, big; Bluestem, Caucasian; Bluestem, Diaz; Bluestem, little; Bluestem, sand; Bluestem, silver; Bluest em, south African; Bluestem, yellow; Bristlegrass, plains; Bromegrass; Broomsedge; Buffalograss; Buffelgrass; Canarygrass, annual; Canarygrass, reed; Caribgrass; Carpetgrass; Carpetgrass, broadleaf; Centipedegrass; Cordgrass, marsh hay; Crabgrass; Curly me squite; Dallisgrass; Dropseed, pine; Dropseed, sand; Dropseed, tall; Fescue; Fingergrass, feather; Foxtail, creeping; Foxtail, meadow ; Gamagrass, eastern; Grass; Grass, galleta; Grass, gama; Grass, muhly; Grass, pasture; Grass, St. Augustine; Grass, wildry e; Grass, zoysia; Hairgrass tufted; Hardinggrass; Indiangrass; Junegrass; Limpograss; Lovegrass; Maidencane; Mannagrass; Millet, foxtail; Millet, Japanese; Molassesgrass; Napiergrass; Needlegrass; Oat, sand; Oat, slender; Oat, wild; Oatgrass; Oatgrass, t al l; Oniongrass; Orchardgrass; Pangolagrass; Panicgrass; Paspalum; Polargrass; Quackgrass; Redtop; Reedgrass; Rhodesgrass; Rhodesgrass, multiflower false; Ricegrass, indian; Ryegrass, Italian; Ryegrass, perennial; Sandreed, prairie; Sixweeks threea wn; Slough grass; Smilograss; Sorghum, forage; Spikeoat; Sprangletop, green; Squirreltail; Sudangrass; Sunolgrass; Tanglehead; Timothy; Timothy, alpine; Trisetum, spike; Vaseygrass; Veldtgrass, perennial; Velvetgrass; Wheatgrass; Wheatgrass, bluebunch; Wheatgrass, cr ested; Wheatgrass, fairway; Wheatgrass, intermediate; Wheatgrass, pubescent; Wheatgrass, Siberian; Wheatgrass, slender; Wheatgrass, streambank; Wheatgrass, tall; Wheatgrass, thickspike; Wheatgrass, western; and Windmillgrass, hooded]

Application to outdoo r growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of di luted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. For rice, a 10 day water hold is required for all applications when rice fields are flooded. Do not wet plants to point of runoff or drip. Application to hydropon ically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.50 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 18: Nongrass Animal Feeds (Forage, Hay, Straw, and Hay) [including Alfalfa; Arrowleaf balsamroot; Burclover; Clover; Clover, alsike; Clover, alyce; Clover, arrowleaf; Clover, ball; Clover, berseem; Clover, bigflower; Clover

, crimson; Clover, hop; Clover, lappa; Clover, persian; Clover, red; Clo ver, rose; Clover, seaside; Clover, strawberry; Clover, striate; Clover, sub; Clover, sweet; Clover, true; Clover, white; Clover, whitetip; Crownvetch; Kudzu; Lespedeza; Lupine; Lupine, forage; Lupine, sweet; Mustard; Sainfoin; Trefoil; Velvetbean; Vetch; and Vetch, milk]

### 74

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applicatio ns: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface app lication to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Crop Group 19: Herbs and Spices [Including Allspice; Angelica; Anise; Anise hyssop (mint); Anise, star; A nnatto; Balm; Basil; Borage; Burnet; Camomile; Caper; Caraway; Caraway, black; Cardamom; Cardamon amomum; Cassia; Catnip; Celery, seed; Chervil; Chive; Chive, Chinese; Cinnamon; Clary; Clove; Coriander; Costmary; Cilantro (False coriander); Cumin; Curry;

D ill; Dillweed; Fennel; Fennel, florence; Fenugreek; Grains of paradise; Horehound; Juniper berry; Lavender; Lemongrass; Lovage; Mace; Marigold, pot; Marjoram (Oregano); Mustard; Nasturtium; Nutmeg; Parsley; Pennyroyal; Pepper, black; Pepper, white; Poppy; Rosemary; Rue; Saffron; Sage; Savory, summer; Savory, winter; Sweet bay; Tansy; Tarragon; Thyme; Vanilla; Wintergreen; Woodruff; and Wormwood]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest press ure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops

. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014
lb/ 1,000 cu. ft 10 0

Miscellaneous Fruit, Subtropical/Tropical [including Acerola; Atemoya, Avocado; Banana; Carob bean; Cherimoya; Date; Durian; Feijoa; Fig; Guava; Kiwifruit; Lychee; Mango; Papaya; Passionfruit; Persimmon; Pineapple; Pomegranate; Rambutan ; and Starfruit (Carambola) ]

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried.
Aeri al applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Vegetable, Oriental [including Artichoke, Chinese; Balsam pear (bitter melon); Bean, mung; Be an, yardlong; Broccoli, Chinese; Cabbage, Chinese, bok choy; Cabbage, Chinese, mustard; Cabbage, Chinese, napa; Coriander (Cilantro); Dasheen; Ginger; Ginseng; Melon, citron; Radish, oriental; Spinach, Chinese; and Waxgourd, Chinese]

Note: Individual c rops listed above belong to various crop groups previously listed.

Application to outdoor growing

crops 0.5 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Application to hydroponical ly grown

crops 1.0 ppm in

water 10 0

### 75

Appendix A

- 1: Food/Feed Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Max. No. of

Applications
Per Season PHI

(Days) Use Directions and Limitations

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 10 0 Do no t harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip. Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

Miscellaneous Commodities: Asparagus; Coffee; Cotton; C ranberry; Grape; Jojoba; Okra; Safflower; Strawberry; Sugarcane; Sunflower; and Tea

Application to outdoor growing

crops 0.5 lb/A 10 14 (cotton seed)

0 (all
other crops) Do not reapply within 3 days except under
extreme pest pressure.
In case of extreme pest pressure, do not reapply
within 24 hours. Do not harvest until spray has dried. Aerial applications: do not apply less than 2 gal. of diluted solution/A to field crops or less than 10 gal. of diluted solution/A to orchard

crops. Do not wet plants to point of runoff or drip For labels with cotton: Do not apply to cotton within 14 days of seed harvest.

. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

Surface application to greenhouse

grown crop 0.012 lb/1,000 sq. ft

or 0.5 lb/A 1 0 0

Space application to greenhouse

grown crop 0.0014 lb/1,000 cu. ft 10 0

RESIDENTIAL

Preharvest Application to Garden Crops (see Agricultural; Preharvest Application to Field, Orchard, and Greenhouse Crops)

Application to outdoor growing crops 0.01 2 lb/1,000 sq. ft

or

0.50 lb/A 10 0 Do not reapply within 3 days except under
extreme pest pressure. In case of extreme pest pressure, do not reapply
within 24 hours. Do not apply more than 1 time per day. Do not harvest until spray has dried.

Do not wet foliage to point of runoff or drip. Application to hydroponically grown

crops 1.0 ppm in

water 10 0

NON

- FOOD CROPS

(Residential and Non

- Residential)

Non

- food Crops in Greenhouse: Ornamental, Flowering and Foliage Plants

Surface applications 0.03 6 lbs/1,000 sq.ft

or

1.5 lb/A NA NA Do not apply more than 1 time per day. Do not wet foliage to point of runoff or drip.

Space spray 0.0042 lbs/1,000 cu.
ft. NA NA

Non

- food Crops Grown Outside: Ornamentals, Flowering and Foliage Plants, and Lawns

S urface applications (including fire ants and turf diagnostic aid) 0.02 lbs/1,000 sq ft

or

1.0 lbs/A NA NA Do not apply more than 1 time per day.
Do not wet plants to point or runoff or drip.

### 76

A

- 2: Non

- Growing Crop Uses

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Postharvest Application to Vegetables, Fruit, and Nuts

Food/Feed Storage Areas

- Full: Po stharvest Application to Apple, Blackberry, Blueberry, Boysenberry, Cherry, Crabapple, Currant, Dewberry, Fig, Gooseberry, Grape, Guava, Loganberry, Mango, Muskmelon, Orange, Peach, Pear, Pea, Pineapple, Plum, Potato, Raspberry, or Tomato in baskets, on tr ucks, in processing plants, in hampers, or in temporary storage areas (including raw stock stacked in yards)

Copra (processed) in baskets, on trucks, in processing plants, in hampers, or in temporary storage areas (including raw stock stacked in the yard)

Postharvest application to Almonds, Peanuts, and Walnuts (English/black) in bulk

Surface

- General 0.1 lb/1,000 sq.
ft Do not apply more than 1 time per day.

Do not reapply within 7 days.
Do not apply more than 10 times to sweet potatoes. Surface

- Direct application to fruits or tomatoes in baskets or hampers 1.6 x 10
- 6 lb/ lb
of fruit or vegetable (1.6 ppm)

Dip or spray 0.004 lbs ai/ gallon

Space

- Fruits, vegetables, and copra

. 0.01 lb/1,000

cu. Ft

Postharvest Direct Application to Bulk G rain and Seed Barley, Beans, Lima Beans, Birdseed, Buckwheat, Cocoa beans, Corn, Cottonseed, Flax, Grain sorghum, Oats, Pea (field), Rice, Rye, Wheat (club, common, durham), Wheat (emmer, spelt)

Bulk Grain and Seed 1.0 lb/1,000 bushels grain Do not reap ply within 30 days.

See below for rate in ounces Piperonyl Butoxide per 100 lb grain or
seed.

- Barley 0.033 oz/cwt

Do not reapply within 30 days. - Beans 0.027 oz/cwt

- Beans, lima 0.029 oz/cwt

- Birdseed 0.032 oz/cwt

- Buckwheat 0.033 oz/cw t

- Cocoa beans 0.037 oz/cwt

- Corn 0.029 oz/cwt

- Cottonseed 0.057 oz/cwt

- Flax 0.029 oz/cwt

- Grain sorghum 0.029 oz/cwt

- Oats 0.050 oz/cwt

- Pea (field) 0.027 oz/cwt

- Rice 0.036 oz/cwt

- Rye 0.029 oz/cwt

- Wheat: club, common, durham 0.027 oz/cwt

- Wheat: emmer, spelt 0.040 oz/cwt

Direct Application to Animals

### 77

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Cattle (Beef/Range/Feeder and Dairy); Hogs/Pig/Swine; Goats (Meat and Dairy); Kids; Sheep; Lamb; Rabbits; Game Animals (including Beefalo, Buffalo, Deer, Exo tics such as European red deer, Llamas, Moose, Elk); Livestock (including Donkeys, Horses, Ponies, Mules); and Poultry

Direct application to livestock and poultry

- Dust 10.0%

Do not apply more than 1 time per day. Do not apply microencapsulated products to lactating or food animals. Direct application to livestock

– Liquid Solution 0.35 lb/gal

Direct application to livestock

- Towelette 2.0%

Direct application to livestock

- Spot

on or Pour

- on 10.0%

Direct application to poultry

– Liquid
Solution 0 .1%

Application to Agricultural Premises and Equipment

- Indoor
Greenhouses (empty)

Agricultural/Farm Structures/Buildings and Equipment: Animal houses; Calf hutches; Calving pens and parlors; Dairies; Dairy farms; Goat houses; Livestock housing struct ures; Loafing sheds; Poultry houses; Poultry operations; Rabbit houses; Rabbit hutches; Stables; Swine houses.

Barns/Barnyards/Auction Barns: Barns (Beef, Cattle, Dairy, Horse, Hog, and Livestock)

Dairy Farm Milking Stalls/Parlors: Milk houses; Milking parlors

Dairy Farm Milk Storage Rooms/Houses/Sheds: Milk rooms

Dairy Farm Milk Handling Facilities/Equipment: Milk handling equipment

Dairy Farm Milking Equipment: Milking equipment

Seed Houses/Stores/Storage Areas/Warehouses: Stored seed warehouses; Seed warehouse bins; Granaries; Seed storage sites; Seed bins; Stable bins; Stored seed warehouses

Silos and Mushroom houses

IMPORTANT NOTE: The following rates allow animals to be present during application.

Surface

– General 0.56 lb ai/ 1,000 sq . ft Remove or cover exposed food and water before application.

When used in dairy barns or facilities: close milk bulk tank lids to prevent contamination from spray and from dead or falling insects.

Remove or cover milking utensils before application.

Was h teats of animals before milking.

Do not apply more than 1 time per day. Space

– General 0.0033 lb ai/ 1,000 cu. ft/application

And

0.008 lbs
ai/1000 cu. ft./day

### 78

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Space

- Metered release 0.008 lbs
ai/1000 cubic feet/day Not for use in Residential areas.

Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install withi n 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Commercial Animal Housing

Animal areas and q uarters; Animal shelters; Catteries; Dog runs; Kennels; Pet grooming shops; Pet stores; Research animal quarters; Zoos. (Animals are not present during application)

Surface

- General 0.56 lb/ 1,000 sq. ft

Do not apply more than 1 time per day.

Remove or c over exposed food and water before application. Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft

Space

- General 0.025 lb/ 1,000 cu. ft

Space

- Metered release 0.008 lbs
ai/1000 cubic feet/day Not for use in Residential areas. Does this incl ude non

- commercial

barns & stables?
Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Outdoor Agricultu ral Premises Empty Uncultivated Agricultural Areas: Corrals; Dairy areas; Farms; Goat holding areas; Hog operations; Rights

- of

- way; Sheep holding areas.

Empty Cattle Feedlots: Beef cattle operations; Feedlots; Holding lots; Livestock lots; Swine lots and yards.

Surface

- General 0.02 lb/ 1,000 sq. ft Do not apply more than 1 time per day. Surface

- Crack and crevice or
spot 0.56 lb/ 1,000 sq. ft

INDOOR

Residential

- Indoor

### 79

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations Household/Domestic Dwellings: Apartments; Cabins; Campers; Condominiums; Dwellings; Homes; Mobile homes; Recreational vehicles; Residences; Public housing; Sheds; Toolsheds; Townhouses.

Household/Domestic Dwelling Contents: Beds (cracks, crevices, framework); Bedding; Bookcases; Box springs; Boxes; Cabinets; Carpet; Cooking eq uipment; Cut Flowers; Drawers; Dressers; Draperies; Dryers; Equipment; Fabrics; Flowering plants; Foliage plants; Formica; Furniture; Furniture bases; Furniture legs; Glass; Light fixtures; Linoleum; Machinery; Mattresses; Picture frames; Plastic fabric ba gs; Refrigerator; Rugs; Shelves; Shrubs; Sofas and Chairs; Sofa and Chair surfaces; Soffits; Stainless steel; Storage drawers; Stored items; Stoves; Tables; Tiles; Trees; Upholstered furniture; Upholstery; Vinyl tile;
Washers.

Household/Domestic Dwelling s Indoor Food Handling Areas (food covered): Cupboards; Kitchens; Sinks; Underneath sinks;
Food areas.

Household/Domestic Dwellings Indoor Nonfood Handling Areas: Attics; Basements; Bedrooms; Closets; Closed porches; Crawl spaces; Dining rooms; Garages; Pantries; Porches; Solariums; Storage areas; Sun porches; Utility rooms; Bathrooms.

Household Domestic Dwellings Indoor Premises: Baseboards; Closed void areas; Cracks and crevices; Dark corners; Doorframes; Door jambs; Doors; Door sills; Drains; Equipmen t voids; False ceilings; Floors; Foundations; Moldings; Moist places; Niches; Pipes; Screens; Soffits; Tunnels and cavities in wood; Walls; Windows; Window frames; Window sills; Weep holes; Woodwork; Voids in attics, walls, ceilings, and equipment.

Electr ical Supplies/Equipment: Meter boxes; Electrical equipment; Electrical fittings.

Human Clothing (Insect and Mold/Mildew Control): Clothing; Clothing (outerwear); Clothing (in storage); Woolens.

Garbage cans and Garbage/trash compactors.

Surface

- Gen eral 0.56 lb/ 1,000 sq. ft Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food processing equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

For articles:

- Do not wet articles to point of runoff or drip.

- Do not use treated article until spray has dried. Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft

Space

– General
NOTE: Deleted the Space

- Metered Release application from the r ow below. 0.025 lb/ 1,000 cu. ft

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not for use in Residential areas.

Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or w ithin 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting m aintenance.
Remove or cover exposed food and water before application.

Commercial/Industrial/Institutional Establishments

- Indoor
Apartments; Auditoriums; Buildings; Churches; Commercial buildings; Correctional facilities; Communications centers;
Courth ouses; Day care centers; Dormitories; Drugstores; Elevators; Equipment voids; Factories; Fake ceilings; Florists; Food service storage and preparation areas; Gas stations; Hotels; Industrial buildings; Industrial installations; Institutions; Interiorscapes ; Jails; Kitchens; Laboratories; Laundry areas; Lavatories; Libraries; Locker rooms; Lathhouses; Missions; Motels; Movie Theatres; Museums; Non

- food areas of commercial buildings; Non

- residential buildings; Offices and office buildings; Other commercial, i ndustrial, and governmental sites; Parking garages; Prisons; Public buildings; Resorts; Schools; Shadehouses; Sheds; Stores; Textile mills & warehouses; Theaters; Universities; Utilities/utility rooms; Health care facilities; Hospices; Hospitals; Nursing h omes; Veterinary clinics.

### 80

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Surface

– General 0.56 lb ai/ 1,000 sq. ft Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food processing equipment, and food preparation surfaces, or wash them thoroughly before us e. Do not apply more than 1 time per day. Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft

Space

– General 0.033 lb/ 1,000 cu. ft

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not for use in Residential areas.

Do not use in nurseri es or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.

Caref ully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Eating Establishments

- Indoor

Eating Establishments (Food Contact) [Equip ment/Utensils; Food Handling Areas; Food Serving Areas]: Cafeterias; Restaurants;
Mess halls

Surface

– General 0.56 lb ai/ 1,000 sq. ft
UNITS? Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food processing eq uipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft Remove or cover exposed food and water before application.

Remove or cover dishes , utensils, food processing equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Space

- General 0.033 lb/ 1,000 cu. ft Do not make space spray applications when facility is in operation.

Du ring space spray operations, cover or remove food. During space spray operations, cover food processing surfaces or clean
after treatment and before use. Do not apply more than 1 time per day.

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not fo r use in Residential areas.

Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Food Handling and Process ing Establishments

- Indoor

### 81

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Food Handling and Processing Plant Premises and Equipment (Food Contact): Bakeries; Bottling plants; Beverage plants; Canneries; Conveying Equipment; Dried fruit processing plants; Feed areas of commercial buildings; Food areas of commercial buildings; Food processing plants; Fruit packing sheds; Mushroom processing plants; Peanut processing plants; Processing area s of dried food products; Tobacco processing plants; Wineries

Meat Processing Plant Premises and Equipment (Food Co ntact): Conveying equipment; Edible product areas of official establishments operating under the meat; poultry; shell egg grading and egg products inspection operations; Meat packing plan ts; Poultry processing plants; Rabbit processing plants; USDA inspec ted meat and poultry plants

Dairies/Cheese Processing Plant Premises and Equipment (Food Contact): Dairies

Egg Processing Plants

Tobacco Processing Plants

Feed Mills/Feed Processing Plants: Conveying equipment; Feed processing and handling sites; Flou r mills; Grain mills; Mills; Milling operations; Roll housing and hoppers; Stored grain mills; Rice mills

Feed/Food Treatment

- Storage/Processing/Handling Equipment: Conveying equipment; Grain handling equipment

Surface

- General

– 0.56 lb ai/ 1,000 s q. ft Do not make space spray applications when facility is in operation.

Remove or cover exposed food and water before application. Remove or cover dishes, utensils, food processing equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft Do not make space spray applications when facility is in operation.

Remove or cover exposed food and water before application. Remove or cover dishes, utensils, food processing equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Space

- General 0.033 lb ai/ 1,000 cu. ft Do not make space spray applications when facility is in operation.

D uring space spray operations, cover or remove food. During space spray operations, cover food processing surfaces or clean
after treatment and before use. Do not apply more than 1 time per day.

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not f

or use in Residential areas.
Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Retail and Storage

- Ind oor Commercial Storage/Warehouses Premises: Brandy storage warehouses; Dried fruit warehouses; Elevators; Food storage areas; Freight containers; Peanut storage warehouses; Spirit storage; Storage areas; Storage areas of dried food products; Stored se ed

w arehouses; Warehouses; Wine storage warehouses; Tobacco warehouses

Food Stores/Markets/Supermarkets Premises and Equipment: Food marketing

- storage

- distribution; Grocery and convenience stores; Stores; Supermarkets; Conveying equipment; Freight containe rs; Stored product areas

Food/Feed Storage Areas

- Full: Stored product areas.

### 82

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Surface

- General 0.56 lb/ 1,000 sq. ft Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food processing equipment, and food
preparat ion surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Surface

- Crack and crevice or spot 0.56 lb/ 1,000 sq. ft Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food processi ng equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day.

Space

- General 0.033 lb/ 1,000 cu. ft Do not make space spray applications when facility is in operation.

During space spray operatio ns, cover or remove food. During space spray operations, cover food processing surfaces or clean
after treatment and before use. Do not apply more than 1 time per day.

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not for use in Residential are as.

Do not use in nurseries or rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Transportation

- Indoor Commercial Transportatio n Facilities: Airplanes; Boats; Box cars; Buses; Cabins and holds of aircraft; Commercial transportation centers; Freight containers; Ocean fright containers; Pallets; Passenger rail cars; Railroad cars; Recreationa l vehicles; Ships & ships‟ holds; Trains ; Trucks; Trailers; Truck trailers; Livestock hauling equipment; Horse trailers.

Commercial Transportation Facilities

– Empty: Grain transportation containers (truck beds; planes; box cars; cargo ship holds);
Pallets.

Commercial Shipping Containers

- Empt y: Grain transportation containers (truck beds; planes; box cars; cargo ship holds);
Pallets.

Trunks of Automobiles, Taxis, Limousines.

Surface

- General 0.56 lb/ 1,000 sq. ft

Do not use in aircraft cabins except in compliance with PR Notice 96

- 3.

Do not apply more than 1 time per day. Surface

- Crack and crevice or spot 2.2 lb/ 1,000 sq. ft

Space

- General 0.033 lb/ 1,000 cu. ft

### 83

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Space

- Metered release 0.05 lbs
ai/1000 cubic feet/day Not for use in Residential areas.

Do not use in nurseries o r rooms where infants, ill, or aged persons are
confined.
Do not place metering device directly over or within 8 feet of exposed feeds, dishes, milking utensils, and feed handling or preparation areas.

Do not install within 3 feet of air vents.
Carefully follow directions for the dispenser unit when installing the dispenser and replacing cans or conducting maintenance.
Remove or cover exposed food and water before application.

Pet Care Birds: Amazon parrots; Budgies; Canaries; Cockatiels; Finches; Love birds; Macaws; Ostrich; Parakeets; Parrots.

Cats (including kittens), Dogs (including puppies), Monkeys, Ferrets, Rabbits.

Chimpanzees; Chinchillas; Horses; Llamas; Lemurs; Minks; Ponies; Pot bellied pigs.

Rodents: Gerbils; Guinea pigs; Hamsters; Mice; Rats.

Shampoos 3.0% a.i. Do not apply to pets less than 12 weeks old.
Consult a veterinarian before applying this product on medicated, debilitated, aged, pregnant, or nursing animals.
Sensitivities may occur after using any pesticide product for pets. If signs of sensitivity occur bathe your pet with mild soap and rinse with large amounts of water. If signs continue, consult a veterinarian immediately. Sprays 0.1% a.i.

Spot

- on or Pour

- on 10.0% a.i.

Dust 10.0% a.i.

Towelettes 2.0% a.i.

Pet Premise Treatment

Pet Living/Sleeping Quarters: Areas of floors & floor coverings wh ere pets may be present; areas where female insects may crawl to lay eggs, and similar hiding places; Dog houses and other sleeping quarters; Dog runs; Pet bedding and premises; Pet premi ses; Pet resting areas; Kennels.

Surface 0.56 lb per 1000 square
fee t

For dusts: Only apply as a spot treatment to areas no greater than 3 feet

by 3 feet per room. Crack and crevice 0.56 lbs ai per 1000 square
feet

Space Spray 0.033 lbs per 1000 square
feet

OUTDOOR

Residential Sites

- Outdoor

### 84

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Ant hills; Ant nests; Ant trails; Backyards; Doors; Driveways; Entranceways; Mud dauber, wasp, and yellow jacket nests; Outside surfaces of buildings; Patio furniture; Picnic areas; Residential areas; Screens; Siding; Spigots; Storage areas; Tree holes; Under eaves; Under sidin g; Wall voids; Windows.

Nonagricultural Outdoor Buildings/Structures: Atriums; Carports; Decks; Fences; Gazebos; Lanais; Porches; Sheds; Tree houses; Tunnels and cavities in wood; Verandas; Tents.

Fencerows; Hedgerows; Nonagricultural Rights

- of

- way; Path s; Patios; Paved Areas: Private Roads; Sidewalks; Garbage bins; Dumpsters; Meter boxes; Electrical equipment; Electrical fittings; Manure; Compost piles.

Surface

– General 0.075 lb ai/ 1,000 sq. ft Do not apply more than 1 time per day.

Remove or cover exposed food and drinking water before application. Surface

- Crack and crevice or spot 0.56 lb ai/ 1,000 sq. ft

General Outdoor Sites including Non

- Agricultural rights

- of

- way, Commercial/Institutional/Industrial Premises and Equipment, Outdoor Eating Establishments, and Utensils

Ant hills; Ant nests; Ant trails; Backyards; Doors; Driveways; Entranceways; Mud dauber, wasp, and yellow jacket nests; Outsi de surfaces of buildings; Patio furniture; Picnic areas; Residential areas; Screens; Siding; Spigots; Storage areas; Tree holes; Under eaves; Under siding; Wall voids; Windows.

Nonagricultural Outdoor Buildings/Structures: Atriums; Carports; Decks; Fences; Gazebos; Lanais; Porches; Sheds; Tree houses; Tunnels and cavities in wood; Verandas; Tents.

Fence rows; Hedgerows; Nonagricultural Rights

- of

- way; Paths; Patios; Paved Areas: Private Roads; Sidewalks; Garbage bins; Dumpsters; Meter boxes; Electrical equipment; Electrical fittings; Manure; Compost piles.

Surface

– General 0.075 lb ai/ 1,000 sq. ft Do not apply more than 1 time per day.

Remove or cover exposed food and drinking water before application. Surface

- Crack and crevice or spot 0.56 lb ai/ 1,000 sq. ft

Outdoor Eating Establishments

Eating Establishments Equipment/Utensils, Food Handling Areas, Food Serving Areas, Non

- Food Areas of outdoor eating
establishments and drive

- in restaurants

Surface applications 0.075 lbs ai/1000 square
feet Remove or cover exposed food and water before application.

Remove or cover dishes, utensils, food proc essing equipment, and food preparation surfaces, or wash them thoroughly before use. Do not apply more than 1 time per day. Crack/crevice or spot surface 0.56 lbs ai/1000 square
feet

Mosquito Abatement

- Adulticide

Agricultural Crops/Soils: Groups of Agricultural Crops Which Cross Established Crop Groupings (Croplands);
Agricultural Uncultivated Areas: Fallow lands, Pastures, and Rangelands;
Intermittently Flooded Areas/Water;
Irrigation Systems

### 85

Appendix A

- 2: Non

- Growing Crop Uses of Piperonyl Butoxide Subject to Reregistration.

Site Application Type Max. Single Application Rate, ai Use Directions and Limitations

Thermal fog

Non

- thermal fog

ULV 0.025 lb/A Do not a pply more than 0.2 lbs ai/acre/year in any treated area.
Apply only when wind speed is greater than or equal to 1 mph.
For ground applications: Spray equipment must be adjusted so that the volume median diameter is less than 30 microns (Dv 0.5 < 30 μm) and that 90% of the spray is contained in droplets smaller than 50 microns (Dv 0.9 < 50 μm).
For aerial applications: Spra y equipment must be adjusted so that the volume median diameter produced is less than 60 microns (Dv 0.5 < 60 μm) and that 90% of the spray is contained in droplets smaller than 80 microns (Dv 0.9 < 80 μm). Apply using a nozzle height of no less than 100 feet above the ground or canopy for aerial applications with fixed wing equipment. Apply using a nozzle height of no less than 75 feet above the ground or canopy for aerial applications with rotary wing equipment.

0.08 lb/A Do not apply more than 0.2 lbs ai/acre/year in any treated area.

Apply only when wind speed is greater than or equal to 1 mph.
For ground applications: Spray equipment must be adjusted so that the
volume median diameter is less than 30 m icrons (Dv 0.5 < 30 μm) and that 90% of the spray is contained in droplets smaller than 50 microns (Dv 0.9 < 50 μm).
For aerial applications: Spray equipment must be adjusted so that the volume median diameter produced is less than 60 microns (Dv 0.5 < 60 μm) and that 90% of the spray is contained in droplets smaller than 80 microns (Dv 0.9 < 80 μm). Apply using a nozzle height of no less than 100 feet above the ground or canopy for aerial applications with fixed wing equipment. Apply using a nozzle heig ht of no less than 75 feet above the ground or canopy for aerial applications with rotary wing equipment.

Manholes

Surface 0.04
lbs/manhole
over a 200 foot length Do not apply more than 1 time per day.

### 86



## Appendix B : PBO Major Degradate Structures

### 87

### 88



## Appendix C : Submitted Effects Studies for Piperonyl Butoxide

71

- 1 Avian Single Dose Oral Toxicity

MRID Citation Reference

41969008 Campbell, S.; Lynn, S.; Smith, G. (1991) An Acute Oral Toxicity Study With

Piperonyl Butoxide in the Northern B obwhite Quail: Lab Project Number: 306

- 103. Unpublished study prepared by Wil

- dlife International Ltd. 35 p.



## 71

- 2 Avian Dietary Toxicity

MRID Citation Reference

00031369 or
00055509 IBT study Fletcher, D. (1974) Report to McLaughlin Gormley King Company: 8

- Day

Dietary LC50 Study with X

- 2840

- 74 in Mallard Ducklings: IBT No. 651

- 05280. (Unpublished study received Dec 17, 1975 under 1021

- 88; prepared by
Industrial Bio

- Test Laboratories, Inc., submitted by McLaughlin, Gormley, King Co., Minneapolis, Minn.; CDL:221996

- N)

00072879 or
00073000 Fink, R. (1975) Final Report: Eight

- Day Dietary LCI50^

-- Mallard Duck: Project

No. 104

- 112. (Unpublished study received Sep 18, 1980 under 279

- 482; prepared by Truslow Farms, Inc., submitted by FMC Corp., Philadel phia, Pa.; CDL:243249

- E) Aldrin + Pipronyl Butoxide + Pyrethrins

000 72999 Fink, R. (1975) Final Report: Eight

- Day Dietary LCI50^

-- Bobwhite Quail:

Project No. 104

- 111. (Unpublished study received Jan 19, 1977 under 4816

- 428; prepared by Truslow Farms, Inc ., sub

- mitted by Fairfield American Corp., Medina, N.Y.; CDL:227641

- B) Aldrin + Pipronyl Butoxide + Pyrethrins

41969006 Grimes, J.; Lynn, S.; Smith, G. (1991) A Dietary LC50 Study With Piperonyl

Butoxide in the Northern Bobwhite Quail: Lab Project Numbe r: 306

- 101. Unpublished study prepared by Wildlife Intern

- ational Ltd. 58 p.

41969007 Grimes, J.; Lynn, S.; Smith, G. (1991) A Dietary LC50 Study With Piperonyl

Butoxide in the Mallard: Lab Project Number: 306

- 102. Unpublished study prepared by Wildlife International Ltd. 57 p.

00031373 Taylor, R.E. (1967) To Determine the Toxicity of Sample on Tropical Fish,

Parakeets and Canaries. (Unpublished study received Dec 17, 1975 under
1021

- 88; prepared by Harris Laboratories, Inc., submitted by McLaughlin, Gormley, King Co., Minneapolis, Minn.; CDL:221996

- R) Aldrin + Pipronyl Butoxide + Pyrethrins



## 71

- 4 Avian Reproduction

MRID Citation Reference

43876301 Rodgers, M. (1995) Piperonyl Butoxide: Effects on Reproduction in Bobwhite

Quail After Dietary Ad ministration: Lab Project Number: PBT/2: PBT 2/950167.

### 89 Unpublished study prepared by Huntingdon Research Centre, Ltd. 258 p.

43876302 Rodgers, M. (1995) Piperonyl Butoxide: Effects on Reproduction in the Mallard

Duck After Dietary Administration: Lab Pro ject Number: PBT/3: PBT 3/950168. Unpublished study prepared by Huntingdon Research Centre, Ltd. 225 p.



## 72

- 1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

000 84069 Lewallen, L.L. (1973) Letter sent to Joseph B. Moore dated Dec 3, 1973 ?Data

on the toxicity of pyrethrim and dimethrin on the mosquito fish~Gambusia affinis~?|. (California, Health and Wel

- fare Agency, Dept. of Health, Vector Control Section; unpub

- lished study; CDL:221987

- AN)

00 107544 Taylor, R. (1967) To Determine the Toxicity of Sample ?Pyrocide Intermediate

6440| on Tropical Fish, Parakeets and Canaries. (Unpublished study received Sep 19, 1969 under 2915

- 14; pre

- pared by Harris Laboratories, Inc., submitted by Fuller Brush Co., Great Bend, KS; CDL:006959

- A ) Aldrin + Pipronyl Butoxide + Pyrethrins

00 111966 Cope, O. (1965) Letter sent to J. Moore dated Mar 16, 1965 ?Tox

- icity figures

for McLaughlin Gormley King compound no. F

- 1755 against bluegill and rainbow trout|. (U.S. Fish and Wildlife Service, Fish

- Pesticide Re search Laboratory; unpublished study; CDL:005246

- A)

40991204 McAllister, W. (1984) Resmethrin: Acute Toxicology of Scourge to Rainbow

Trout (Salmo gairdneri) (432

- 667): Laboratory ID: 31370. Unpublished study prepared by Analytical Bio

- Chemistry Labora

- tories, Inc. 58 p. Scourge MF =
46% PB + 18 % R

40991205 Bills, T.; Marking, L.; Dawson, V. (1985) Acute Toxicity of Pipe

- ronyl Butoxide

to Selected Species of Fish. Unpublished study prepared by US Fish & Wildlife Service. 158 p. Check Mayer and Elle rsieck

41153301 McAllister, W. (1984) Resmethrin: Acute Toxicity of Scourge to Bluegill Sunfish

(Lepomis macrochirus): Laboratory ID No. 31371: ABC Protocol No. 7601. Unpublished study prepared by Analytical Bio

- Chemistry Laboratories, Inc. 58

p.

4254030 2 Holmes, C.; Smith, G. (1992) A 96

- hour Flow

- through Acute Toxicity Test with

Piperonyl Butoxide in the Bluegill (Lepomis macrochirus): Amended Final Report: Lab Project Number: 306A

- 101. Unpublished study prepared by Wildlife International Ltd. 195 p.

42540303 Holmes, C.; Smith, G. (1992) A 96

- hour Flow

- through Acute Toxicity Test with

Piperonyl Butoxide in the Rainbow Trout (Oncorhynchus mykiss): Amended Final Report: Lab Project Number: 306A

- 106: PWR3. Unpublished study prepared by Wildlife Internatio nal Ltd. 191 p.

43082302 Machado, M. (1994) Pyrenone Crop Spray (Sample Ref. 13650): A Flow

Through Acute Toxicity Test with Bluegill Sunfish (Lepomis macrochirus): Final Report: Lab Report Number 93/11/5008. Unpublished study prepared by Springborn Labo ratories, Inc. 66 p.

00031373 Taylor, R.E. (1967) To Determine the Toxicity of Sample on Tropical Fish,

### 90 Parakeets and Canaries. (Unpublished study received Dec 17, 1975 under
1021

- 88; prepared by Harris Laboratories, Inc., submitted by McLaughlin, Gorml ey, King Co., Minneapolis, Minn.; CDL:221996

- R)

40094602 Johnson, W.; Finley, M. (1980) Handbook of Acute Toxicity of Chemicals to

Fish and Aquatic Invertebrates: Resource Publi

- cation 137. US Fish and Wildlife Service, Washington, D.C. 106 p.

40098001 Mayer, F.; Ellersieck, M. (1986) Manual of Acute Toxicity: Inter

- pretation and

Data Base for 410 Chemicals and 66 Species of Freshwater Animals. US Fish & Wildlife Service, Resource Pub

- lication 160. 579 p.



## 72

- 2 Acute Toxicity to Freshwater Inver tebrates

MRID Citation Reference

40991208 McAllister, W. (1984) Resmethrin: Acute Toxicology of Scourge to (Daphnia

magna) (432

- 667): Laboratory ID: #31372. Unpublished study prepared by Analytical Bio

- Chemistry Laboratories, Inc. 35 p.

40991209 Forbis, A. (1986) Acute Toxicity of Piperonyl Butoxide Technical to Daphnia

magna: Laboratory ID: 34490. Unpublished study prepared by Analytical Bio

Chemistry Laboratories, Inc. 43 p.

42540301 Holmes, C.; Smith, G. (1992) A 48

- hour Flow

- through Acute Toxicity T est with

Piperonyl Butoxide in Daphnids (Daphnia magna): Amended Final Report: Lab Project Number: 306A

- 105A. Unpublished study prepared by Wildlife International Ltd. 208 p.

43858301 Ward, G. (1995) Scourge: Acute Toxicity to the Water Flea, Daphnia mag na,

Under Flow

- Through Test Conditions: Lab Project Number: F602: J9308003D. Unpublished study prepared by Toxikon Environmental Sciences. 87 p.

TN 870 USEPA Beltsville Animal Biology Lab study with Daphnia magna.



## 72

- 3 Acute Toxicity to Estuarine/ Marine Organisms

MRID Citation Reference

00 109941 Heitmuller, T. (1975) Acute Toxicity of Pyrenone to Pink Shrimp (Penaeus

duorarum) and Fiddler Crabs (Uca pugilator). (Unpub

- lished study received Sep 17, 1975 under 4816

- 178; prepared by Bionomics, EG & G, Inc., submitted by Fairfield American Corp., Medina, NY; CDL:165023

- C)

40991211 Ward, G. (1986) Acute Toxicity of Piperonyl Butoxide Technical to the Embryos

and Larvae of the Eastern Oyster (Crassostrea vir

- ginica): (432

- 209): Laboratory ID: D

- EC86. 2/PBT

- OE. Unpublished study prepared by Environmental Science & Engineering, Inc. 28 p.

40991213 Ward, G. (1984) Resmethrin: Acute Toxicity of Scourge to Pink Shrimp

(Penaeus duorarum) and Sheepshead Minnow (Cyprinodon variegatus): (432

- 667): Laboratory ID: #BP

- 84

- 3

- 19. Unpublished study prepared by Springborn Bionomics, Inc. 28 p.

### 91

40991216 Surprenant, D. (1986) Resmethrin: Acute Toxicity of SBP

- 1382, 40 MF to

Embryos

- Larvae of the Quahog Clam (Mercenaria mercenaria): (432

- 596): Laboratory ID: # BW

- 86

- 1 2

- 2214. Unpublished study prepared by Springborn Bionomics, Inc. 33 p.

40991219 Ward, G. (1986) Acute Toxicity of Piperonyl Butoxide Technical to the Pink

Shrimp (Penaeus duorarum): (432

- 209): Laboratory ID: D

- ECBI.2/PS

- PBT. Unpublished study prepared by Environmental Science & Engineering, Inc. 29

p.

40991220 Ward, G. (1986) Acute Toxicity of Piperonyl Butoxide Technical to the

Sheepshead Minnow (Cyprinodon variegatus): (432

- 209): Lab

- oratory ID: D

ECBI.2/SHM

- PBT. Unpublished study prepared by Environm ental Science & Engineering, Inc. 31 p.

42540304 Holmes, C.; Smith, G. (1992) A 96

- hour Flow

- through Acute Toxicity Test with

Piperonyl Butoxide in Sheepshead Minnow (Cyprinodon variegatus): Amended Final Report: Lab Project Number: 306A

- 108A: PWR3. Unpu blished study prepared by Wildlife International Ltd. 207 p.

42540305 Holmes, C.; Smith, G. (1992) A 96

- hour Shell Deposition Test with Piperonyl

Butoxide in the Eastern Oyster (Crassostrea virginica): Amended Final Report: Lab Project Number: 306A

- 110A: DBR31. Unpublished study prepared by Wildlife International Ltd. 208 p.

42540306 Holmes, C.; Smith, G. (1992) A 96

- hour Flow

- through Acute Toxicity Test with

Piperonyl Butoxide in Mysid Shrimp (Mysidopsis bahia): Amended Final Report: Lab Project Number : 306A

- 109: PWR3. Unpublished study prepared by Wildlife International Ltd. 206 p.

43858302 Ward, G. (1995) Scourge: Acute Effect on New Shell Growth of the Eastern

Oyster, Crassostrea virginica: Lab Project Number: J9308003F. Unpublished study prepared by Toxikon Environmental Sciences. 94 p.

43901801 Roberts, C.; Swigert, J. (1995) Piperonyl Butoxide: A 96

- Hour Flow Through

Acute Toxicity Test with the Saltwater Mysid (Mysidopsis bahia): Final Report: Lab Project Number: SDR20: 306A

- 111A. Unpublished study prepared by Wildlife International Ltd. 46 p.

000 84053 Frederick, J.J. (1974) Toxicities of Some Mosquito Adulticides to Non

- target

Marine Organisms. (Monroe County (Florida), Mosquito Control District;
CDL:221987

- Q)



## 72

- 4 Fish Early Life St age/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

000 31368 Rausina, G. (1974) Report to McLaughlin Gormley King Company: Four

- Day

Static Fish Toxicity Studies with X

- 2840

- 74 in Rainbow Trout and Bluegills: IBT
No. 621

- 05281. (Unpublished study received Dec 17, 1975 under 1021

- 88; prepared by Industrial Bio

- Test Laboratories, Inc., submitted by McLaughlin, Gormley, King Co., Minneapolis, Minn.; CDL:221996

- M) Aldrin + Pipronyl Butoxide + Pyrethrins

### 92

000 42583 Bentley, R.E. (1975) Acute Toxici ty of Pyrenone O.T. 75

- 7.5 to Bluegill

(?~Lepomis macrochirus~?) and Rainbow Trout (?~Salmo ?~gairdneri~?): NCT 589:61. (Unpublished study received Sep 18, 1980 under 279

- 482; prepared by Bionomics, EG&G, submitted by FMC Corp., Philadelphia, Pa.;
CDL:2432 49

- D)

40991224 Bills, T.; Marking, L.; Dawson, V. (1986) Chronic Toxicity of Piperonyl Butoxide

to Developing Rainbow Trout (Salmo gairdneri). Unpublished compilation prepared by US Dept. of the Interior, National Fishing Research Laboratory. 142 p.

41 081901 McAliister, W. (1986) Early Life Stage Toxicity of ?Carbon|

- Pipero

- nyl Butoxide

to Fathead Minnows (Pimephales promelas) in a Flow

- through System: Final Report # 34562. Unpublished study pre

- pared by Analytical Bio

- Chemistry Laboratories, Inc. 38 p.

42335902 or 42538802 Holmes, C.; Smith, G. (1992) A Flow

- through Life

- Cycle Toxicity Test with

Piperonyl Butoxide in Daphnids (Daphnia magna): Final Report: Lab Project
Number: 306A

- 104. Unpublished study prepared by Wildlife International Ltd. 224 p

.

43300301 Machado, M. (1994) Piperonyl Butoxide Technical Task Force Blend PB200

-

The Toxicity to Fathead Minnow (Pimephales promelas) During an Early Life

stage Exposure: Amended Final Report: Lab Project Number: 94

- 5

- 5264: 13513.0194.6102.120: 90/FIFRA /72

- 4/FM

- ELS. Unpublished study prepared by Springborn Labs, Inc. 86 p.

43311301 Putt, A. (1994) Piperonyl Butoxide Technical Task Force Blend PB200

- The

Chronic Toxicity to Daphnia magna under Flow

- Through Conditions: Lab Project Number: 94

- 5

- 5270: 13513 .0194.6101.130. Unpublished study prepared by Springborn Labs., Inc. 105 p.

47860901 Cathcart, C. (2009) Waiver Request

- Regarding Requirement for Mysid

Chronic Toxicity Study for Piperonyl Butoxide. Unpublished study prepared by Piperonyl Butoxide Task Force II. 4 p.



## 72

- 5 Aquatic Field study

40695801 Sjogren, R. (1986) Results of Scourge and Resmethrin 40 MF Field Applications

against Rainbow Trout in Aquaculture Ponds in Central Minnesota, September 1986: Laboratory Project ID: LG402. Unpublished stud y prepared by Mosquito Control Technology in cooperation with Penick Bio UCLAF. 67 p.

40695802 Pierce, R. (1986) Acute Toxicity of Scourge on Select Estuarine Or ganisms

during Field Applications. Unpublished study prepared by Mote Marine Laboratory in co operation with Louisiana State University. 21 p.



## 141

- 1 Honey bee acute contact

MRID Citation Reference

41969009 Lynn, S.; Hoxter, K. (1991) An Acute Contact Toxicity Study With Piperonyl

Butoxide with the Honey Bee: Lab Project Number: 306

- 104. U npublished study

### 93 prepared by Wildlife International Ltd. 31 p.

00 140615 Johansen, C.; Eves, J. (1971) Bee Research Investigations, 1971: ?Sevin &

Others|. (Unpublished study received Feb 3, 1972 under 1021

- 1026; prepared by Washington State Univ., Dept. of Ento

- mology, submitted by McLaughlin Gormley King Co., Minneapolis, MN; CDL:005289

- A)



## 141

- 2 Honey bee residue on foliage

MRID Citation Reference

44501701 Hoxter, K.; Palmer, S.; Krueger, H. (1998) Scourge Insecticide: A Foliage

Residue Toxicit y Study with the Honey Bee: Lab Project Number: 312

- 111: CO97W500. Unpublished study prepared by Wildlife International Ltd. 28 p.

47431601 Sindermann, A.; Porch, J.; Krueger, H. (2008) Multicide Fogging Concentrate

2798: A Foliage Residue Toxicity Study with the Honeybee: Final Report. Project Number: 163/123, 163/080107/BFR/SUB16. Unpublished study prepared by Wildlife International Ltd. 37 p.

Piperonyl butoxide + Phenothrin + Prallethrin mixture



## 142

- 3 Simulated or Actual Field Testing

MRID Cita tion Reference

00 107568 Schuyler, K.; Massing, R. (1973?) Observations on Ground ULV Appli

- cations of

Synergized Pyrethrins on Non

- target Insects and Mosquitoes in Centre County, Pennsylvania. (Pennsylvania, Dept. of Environmental Resources, Bureau of
Co mmunity Environmental Control; unpublished study; CDL:018069

- B)



## 850.4100 Terrestrial plant toxicity, Tier 1 (seeding emergence)

MRID Citation Reference

47431602 Porch, J.; Krueger, H. (2008) Multicide Fogging Concentrate 2798: A Toxicity

Test to D etermine the Effects of the Test Substance on Seedling Emergence of Ten Species of Plants: Final Report. Project Number: 163/124. Unpublished study prepared by Wildlife International Ltd. 58 p. Piperonyl butoxide +
Phenothrin + Prallethrin mixture



## 850.41 50 Terrestrial plant toxicity, Tier 1 (vegetative vigor)

MRID Citation Reference

47431603 Porch, J.; Krueger, H. (2008) Multicide Fogging Concentrate 2798: A Toxicity

Test to Determine the Effects of the Test Substance on Vegetative Vigor of Ten Spe cies of Plants: Final Report. Project Number: 163/125. Unpublished study

### 94 prepared by Wildlife International Ltd. 79 p. Piperonyl butoxide + Phenothrin +
Prallethrin mixture



## Non Guideline Selections

000 11488 Frederick, J.J. (1974?) Toxicities of some mosq uito adulticides to non

- target

organisms. Pages 56

- 59,~In~Report of 45th Annual Meeting; 1974. Florida Anti

Mosquito Association. (Also ~?In~unpublished submission received Feb 8, 1977
under 20954

- 1; submitted by Zoecon Corp., Palo Alto, Calif.; CDL:231486

- AM)

000 42368
00042913
00110077 McLaughlin, Gormley, King Company, Incorporated (19??) Toxicity of Piperonyl

butoxide to Warm

- Blooded Animals. (Unpublished study received Nov 19, 1964 under unknown admin. no.; CDL:104177

- A)

000 81019 Baker, G.J. (1963) The dual synergist system of piperonyl butoxide and MGK

264. Pyrethrum Post 7(1):16

- 18. (Also~In~unpublished submission received Jan 5, 1966 under 6H1946; submitted by McLaughlin, Gormley, King Co., Minneapolis, Minn.; CDL:221620

- H)

00 107551 Pimentel, D. (1971) Ecological Effects of Pesticides on Non

- target Species. By

Cornell Univ., Dept. of Entomology and Limnology. (S.l.): Executive Office of the President, Office of Science and Technology. (Pages 66

- 67 only; available from: Superintend

- ent of Documen ts, U.S . Government Printing Office, Washington, DC 20402; stock no. 4106

- 0029; published study; CDL:005501

- B)

00 122493 Verece, R.; Malone, J. (1970) Inhalation and Dermal Toxicity of

Bioallethrin/Piperonyl Butoxide and Pybuthrin Aerosol Formula

- tions t o Canaries and Budgerigars: Report Series B No. 82

- 70. (Unpublished study received Sep 22, 1972 under 1021

- 1217; sub

- mitted by McLaughlin Gormley King Co., Minneapolis, MN; CDL: 051098

- G)

42335901 Holmes, C.M. and G.J. Smith (1992) Determination of the Stability of Piperonyl

Butoxide in Fresh and Salt Water. Project No. 306A

- 103. Prepared by Wildlife International Ltd., Eastern, MD. Submitted by Piperonyl Butoxide Task Force II, Washington, DC (EPA MRID No. 42335901)